Hyperguides
Eye health, vision and ophthalmic surgery.
Radial keratotomy (RK) surgery was performed on my left eye several years prior to developing bilateral cataracts. My markedly dominant left eye was distance corrected and my nondominant right eye was kept at near…
In the 1960s, removing a cataract through a 3-mm incision was considered impossible. Doing the "impossible" required a resolution of contradictions which was attained through ingenious application of new technology. As…
The standard conjunctival incision used in extraocular muscle surgery is a peritomy at the limbus. The conjunctiva and Tenon's capsule are incised as a single tissue plane in the limbal incision. This approach is useful…
LASIK has been well accepted as the surgical standard of care for the correction of refractive error. Unlike phacoemulsification for cataract surgery, which has relatively well-established application guidelines for its…
Acanthamoeba keratitis is an uncommon, sight-threatening condition that primarily affects contact lens wearers but may affect other individuals, as well. Men and women are equally affected and the majority of cases are…
Presbyopia is the gradual, age-related loss of accommodation. Unlike other refractive errors, presbyopia affects everyone at some point in his or her lifetime. Understanding the cause of this inevitable phenomenon…
Esotropia is a convergent (inward) deviation of the eyes. Accommodative esotropia is an inward deviation of the eyes due to an activation of the accommodation reflex, which controls ocular accommodation, convergence and…
Acute conjunctivitis in children is usually caused by bacteria, viruses, or allergy. The differential diagnosis of conjunctival inflammation includes nasolacrimal duct obstruction, trauma, corneal abrasions, ulcers, and…
In this tutorial, a few concepts regarding the way light rays interact with thick lenses, that is, real lenses we use, are discussed. Next, the different kinds of magnification of images produced by lenses and the…
Age-related changes in a normal cornea present issues for potential refractive surgery patients of all ages. These issues include whether corneal-based procedures are safe in young people, if older patients respond…
It is the above features that are responsible for the majority of vision loss in patients with AMD. Neovascular AMD most often occurs along with features of nonneovascular AMD but may rarely occur without the atrophic…
Allergic conjunctivitis is one of the most common external ocular conditions encountered in a general ophthalmic practice. Pediatricians, general practitioners, and internists also encounter patients with allergic…
Despite numerous reports in the literature, amiodarone optic neuropathy remains a controversial subject.1-19 Issues associated with amiodarone optic neuropathy have medicolegal and medical implications. In February…
Recession of the rectus muscles is a common strabismus surgical procedure. This procedure involves removal and reattachment of a muscle on the globe so that its new insertion is closer to the muscle origin, usually…
In the late 1970s, the pharmacologic treatment of strabismus was pioneered by Scott,1,2 who experimented with the direct injection of various neurotoxins into the extraocular muscles. Scott correctly theorized that the…
The mechanisms that underlie aqueous production and drainage are complex. To understand the glaucomas, the basic anatomy and physiology of aqueous humor production and drainage must first be mastered. The tutorial is an…
The challenges surgeons face in lens/IOL surgery — to identify and obtain the elusive "state of the art" status — can be staggering. Many of these challenges are described in this tutorial.
Anisometropia is an unequal refractive error in both eyes of an individual. Because truly identical refractive errors in eyes is not the norm, clinical usage of the term anisometropia is reserved for patients with…
Congenital cataract is one of the common ocular disorders responsible for causing blindness in children when not surgically removed promptly or properly.1,2 Congenital cataract removal may result in posterior capsular…
In previous publications,1-7 I discussed the concept of upper eyelid crease configurations and the essential steps required for predictable placement of a lid crease among Asian patients without a crease. My method…
The surgical management of paralytic strabismus often involves the transposition of extraocular muscles to provide rotational force in the field of action of the paralyzed muscle. In addition, the transposition often is…
Lamellar corneal surgery originated in the pioneering works of Jose Ignacio Barraquer, MD, who was the first to report on both the theoretical and practical use of this surgical approach to modify the refractive state…
In order to understand the way light behaves, it is best to divide its properties into two different realms. For example, physical optics helps to explain how light has different colors, how lasers produce such energy,…
Ball bearing (BB) and pellet gun-related injuries represent an important public health concern in the United States. Most of these injuries occur in children and teenagers 19 years of age or younger. In all incidents of…
Eyelid lesions can be benign, premalignant, or malignant. The history and clinical diagnosis are extremely important in determining the probability of malignancy. The growth rate, change in size or color, sun exposure,…
Blepharitis, inflammation or infection of the eyelid margins, is one the most common ophthalmological complications as well as one of the most difficult conditions to treat.1,2 Blepharitis is classified as either…
Introduction The term blepharoplasty comes from the Greek words blepharon (eyelid) and plasso (surgical procedure for repair of a defect or restoration of form or function). The conditions requiring blepharoplasty can…
The two most common conditions that are characterized by involuntary movements of the face are blepharospasm and facial spasm (hemifacial spasm).
Orbital fractures are seen commonly in patients who have blunt trauma to the face and skull. The orbit is involved in trauma since it assumes a prominent position with regard to the craniofacial skeleton.1 These…
Botulinum A Toxin, which is commercially available as Botox (Allergan), is one of seven toxins produced by Clostridium botulinum, a gram-positive anaerobic bacterium. After the clinical trials conducted by Alan B.…
Branch retinal vein occlusion (BRVO) is a retinal vascular disorder seen most frequently in the elderly population (median age of 66 years). The Beaver Dam Eye Study reported that the prevalence and 5-year incidence of…
Duke-Elder's classic ophthalmology textbook classifies brow and lash abnormalities into three main categories1:
Dye staining of the anterior capsule is one of the most important advances in the management of complicated cataracts. With the recent U.S. Food and Drug Administration approval of trypan blue, U.S. surgeons are able to…
Oral carbonic anhydrase inhibitors (CAIs) were introduced for the treatment of glaucoma in 1954 by Becker1 and Grant.2 Their chronic use has become limited because they are poorly tolerated and because of their…
Among the operative challenges faced by the cataract surgeon, the miotic pupil is the most common obstacle. The miotic pupil is also a condition that is associated with the greatest likelihood for intraoperative…
Cataracts occur commonly in patients with uveitis for at least two reasons. First, and most importantly, uveitis itself promotes cataract formation. In fact, patients who have more severe or more frequent bouts of…
Before performing any initial incision (scleral tunnel, corneal scleral, or a clear corneal), the paracentesis port should be made approximately 70° from the center of the planned surgical wound. This provides optimum…
Applanation tonometry has been the clinical gold standard for intraocular pressure (IOP) determination and the management of glaucoma for almost 50 years. Although Goldmann acknowledged the variable influence of central…
Central retinal vein occlusion (CRVO) is one of the most common retinal vascular disorders. The Beaver Dam Eye Study found that CRVO had a prevalence of 0.1% and a 5-year incidence of 0.2%.1 It typically presents as…
In most cases of CSC, the serous retinal detachments are self-limited and resolve without intervention. Visual acuity typically remains excellent with most patients retaining a final visual acuity of 20/40 or better.…
This tutorial reviews the natural history and treatment outcomes of subfoveal choroidal neovascularization (CNV) in ocular histoplasmosis syndrome, idiopathic cases, pathologic myopia, and angioid streaks. In these…
Over the years, many classifications of ptosis have been developed. However, recently with refinements in the diagnosis of ptosis, along with improved anatomic evaluation and study of the pathophysiology of certain…
The field of ophthalmology relies heavily on the development and use of instruments to obtain measurements that allow a clinician to diagnose and treat (and, hopefully, improve the lives of) patients. Some instruments…
For the past decade, cataract surgeons have been following the progress and development of laser phacoemulsification systems.1-6 This technology has always promised two potential advantages. First, a system that…
Potential causes of increased postoperative swelling include rough tissue handling, poor wound placement, excessive cauterization, and lymphatic disruption. Another contributing factor is poor patient compliance with…
New insights into the facial aging process and the introduction of safer, longer-lasting materials for adding volume to facial structures has added a new dimension to noninvasive facial rejuvenation. Since the…
Ultra-short pulsed femtosecond (FS) lasers (Intralase, Irvine, Calif. and Femtec, 2010 Perfect Vision, Germany) now offer an alternative to blade-assisted mechanical microkeratomes for the creation of lamellar…
Cataract surgery with intraocular lens (IOL) implantation has evolved in the past 2 decades. The use of phacoemulsification through a small, clear corneal incision continues to increase yearly.1 IOLs have also evolved…
Ptosis is one of the most common disorders encountered in ophthalmic plastic surgery. A thorough history taking and physical examination of a patient with ptosis provide the guidelines for making an appropriate choice…
Supported in part by an unrestricted research grant from Research to Prevent Blindness, Inc., New York, New York
Incisions, laser ablation, and heat have been used to modify corneal curvature for the correction of refractive error and various pathological conditions. Excimer laser ablation of the corneal periphery in the form of…
Primary congenital glaucoma is the most common type of glaucoma in children; however, it occurs less frequently than the primary glaucomas that are seen in adults (Slide 1). It has been estimated that every…
The development of the lacrimal drainage system begins at approximately 6 week's gestation. Canalization of the ectodermal cord begins during the third month in the area of the medial canthus. Canalization progresses…
Congenital corneal opacities are probably one of the most feared topics for ophthalmic residents and ophthalmologists. The occasion of a neonate with a congenital corneal opacity is a time of great concern in the…
During the first month of life, ocular deviations are common and do not always indicate an abnormality. Oculomotor instability may impede adequate assessment of alignment. A more accurate assessment of motility becomes…
Congenital ptosis, or dysmyogenic ptosis, is the most common ptosis seen in childhood. It is caused by primary dystrophy of the levator muscle. In congenital ptosis, Müller superior tarsal muscle is normal.1 A decrease…
Meibomian gland dysfunction, which is a condition associated with obstruction and inflammation of the meibomian glands, is a widespread and chronic problem that is seen frequently in general ophthalmology and…
Although ocular exposure to light is an obvious necessity for sight, it has been implicated as a causative element in a host of disorders of the human eye, involving structures including the cornea and ocular surface,…
Complications of the corneal epithelium after cataract surgery and IOL implantation are rare. However, these complications should be identified and treated.
Over the past several years, the concept of refractive cataract surgery has received increased attention from surgeons, and the need for its adoption has recently been made urgent by the approval and availability of new…
Corneal topography was developed as the result of several progressively more sophisticated technical innovations over the past century and a half. The roots of videokeratoscopy extend back to the first keratometer,…
As refractive surgery has grown in popularity over the last decade, the types of surgical options available to correct a patient’s refractive error have also increased in number and become more complex. A recent annual…
Whereas most patients who receive state-of-the-art sutureless cataract surgery have excellent unaided vision postoperatively, patients with significant preexisting astigmatism cannot achieve the same results without…
Hydrodissection of the nucleus in cataract surgery has traditionally been perceived as the injection of fluid into the cortical layer of the lens under the lens capsule to separate the lens nucleus from the cortex and…
Cortical removal is perhaps the most overlooked step of cataract surgery, but it is the most important step in reducing the incidence of the most common complication of cataract surgery - posterior capsule opacification…
SLIDE 1 SLIDE 2 The primary clinical etiology of recurrent corneal erosions or recurrent erosion syndrome include epithelial dystrophies (map dot fingerprint dystrophy, also known as epithelial basement membrane…
Cystoid macular edema (CME) is an important cause of visual loss in a large number of surgical and nonsurgical conditions. The diagnosis of CME is usually straightforward and based on clinical and angiographic criteria.…
Complex clinical problems in corneal and external disease often leave both the patient and the physician perplexed. I have found that cytology may be of benefit in helping to narrow the differential diagnosis.1 In some…
Dermoid cysts are choristomas that result secondary to a sequestration of embryonal surface ectoderm between fetal lines of bone closure.1-3 Histopathologically, dermoid cysts are composed of a keratinized squamous…
The color of any visual stimulus may be defined as the result of a certain spectral analysis performed by the brain of the light reflected or emitted. In approximately 92% of individuals, such spectral analysis yields…
The prevalence of diabetic retinopathy increases with the age of the patient and the duration of diabetes. After 20 years of diabetes, 99% of insulin-dependent diabetics and 60% of non-insulin-dependent diabetics show…
Coats' disease is a well-known ocular disorder characterized by congenital retinal telangiectasia, retinal exudation, and exudative retinal detachment.1-3 Clinical variations and methods of treatment for Coats' disease…
Dry eye is a common condition seen with increased prevalence in patients with autoimmune disease1 and in the elderly. In a population-based prevalence study of individuals 65 years of age or older, 14.6% of 2,482…
Dry eye syndrome (DES) is a complex and prevalent disease that affects approximately 12% of the United States' population. The condition affects more than 3.2 million American women who are middle-aged or older.1 In…
There are more than 2 million cataract surgeries performed each year in the United States. Fortunately, the incidence of postoperative endophthalmitis is relatively low, with an estimated five to 10 cases per 10,000.1,2…
New lamellar techniques for replacing damaged or diseased corneal endothelium are rapidly improving transplant outcomes and reducing the surgical risks for patients with endothelial dysfunction.1 These new techniques…
A continuous curvilinear capsulorhexis of the anterior lens capsule is commonly performed during surgery for cataracts to allow a safe manipulation within the capsular bag during the surgery and a stable centration of…
The surgical procedure to remove an eye should be performed with efforts to minimize cosmetic deformity. The anophthalmic socket must be able to hold a prosthesis and allow movement of the prosthesis that matches the…
Langerhans first described dendritic cell histopathology in 1868. Eosinophilic granuloma is part of a spectrum of histiocytic disorders. These disorders were originally named histiocytosis X in 1953 by Lichtenstein, but…
Glaucoma is the leading cause of blindness among adult African-Americans and the second leading cause of blindness among adult Americans ages 18 to 65.1 An estimated 80,000 Americans are legally blind from glaucoma…
Essential blepharospasm, also called benign essential blepharospasm, is a focal cranial dystonia consisting of involuntary contractions of the obicularis oculi muscles and other muscles of the upper face. These…
It is important for refractive surgeons to be aware that all LASIK procedures affect the ocular surface and tear film dynamics. The LASIK procedure may have an impact on corneal sensation, aqueous tear production, and…
Congenital esotropia is a large-angle esodeviation that is present by age 6 months. It represents the most common form of strabismus, with an incidence of 1% to 2%.1 The accepted treatment is eye muscle surgery to…
Evisceration has been an important technique in ophthalmology for almost 200 years. According to Meltzer it was first described by Bear in 1817, who used the procedure after an iridectomy for acute glaucoma was…
The variety of commercially available excimer laser systems has grown in proportion to the popularity of laser in situ keratomileusis (LASIK). Millions of these surgeries are expected to be performed worldwide in the…
Eye pain is a common and often frustrating complaint of patients. This tutorial reviews the common causes of eye pain and discusses patients who have an abnormal eye examination (eg, optic neuritis, uveitis, orbital…
Eyelid infections comprise a heterogeneous group of anatomic substrates and etiologic agents. Clinical findings and treatments vary according to the substrate and agent. The complex anatomy of the eyelid contributes to…
The eyelid may be a common site for the manifestation of several systemic diseases. Because several structures of the eyelid share a common ectodermal origin with the skin, many diseases may exhibit both dermatologic…
When a lesion is to be resected, complete excision can be performed in a variety of techniques. Mohs resection is usually worthwhile for recurrent lesions, extremely invasive, large lesions or tumors involving the media…
Normal eyelids protect the globe from desiccation and trauma, exhibit specialized movement, and allow for vision and movement of fluid bathing the cornea. The upper eyelid margin is normally situated 1.5 mm to 2 mm…
Patients with ocular adnexal trauma often have other significant multisystem injuries. Therefore, awareness of establishing an adequate airway, controlling excessive bleeding, and stabilizing patients' circulatory…
The eyelids first develop in the seventh week of gestation as definite folds forming a circular palpebral aperture. The mesenchymal portion of the upper eyelid develops from a medial and lateral portion of the…
Keratoconus and pellucid marginal degeneration (PMD) are progressive corneal diseases with bilateral corneal thinning that result in corneal distortion and reduced vision. A typical clinical presentation is shown in…
It has been more than one-half of a century since the first intraocular lens (IOL) was implanted by Harold Ridley on November 29, 1949, at St. Thomas Hospital in London.1 Dr. Ridley replaced the cataractous natural…
Beginning with the silicone taco lens, many ophthalmologists predicted that foldable IOLs were simply a flash in the pan and not going to have any lasting impact. Early on, people reported that some of these lenses were…
Fuchs’ endothelial dystrophy is a common bilateral hereditary posterior corneal dystrophy marked by progressive endothelial degeneration (Slide 1). Cornea guttata is a hallmark of Fuchs’ endothelial dystrophy, and…
The aging population in the United States will cause a demographic shift in medical care. The aging boom is due in part to the increase in average life expectancy (75.5 years in 1991) and the aging of post-World War II…
Although the achievement of uncorrected 20/20 visual acuity remains a laudable target for any cataract or refractive surgeon, the goal of high-quality vision increasingly reflects our understanding of the visual system…
Giant cell arteritis is a systemic, chronic inflammatory disease of the elderly that primarily affects medium- to large-sized arteries including the aorta. Early recognition, evaluation, and treatment are critical…
Many methods have been used to shunt aqueous out of the anterior chamber. Wicks or tubes made of various materials have been described since the early 1900s; however, none proved safe and effective. In 1969, Molteno…
Episcleral venous pressure (EVP) plays an important role in IOP regulation. EVP venous pressure can be raised due to obstruction or shunting of blood through several pathways due to a variety of clinical disease…
Graves orbitopathy varies widely in its pattern of clinical presentation. Generalizations about the disease are not particularly useful when developing treatment plans for an individual patient, but the following…
The diagnosis of Duane’s Retraction syndrome (DRS) is not difficult when patients present with the classic features: abduction and adduction deficiency, retraction of the globe, and narrowing of the palpebral fissure on…
Prescribing eyeglasses in young children is a particular dilemma for eye care professionals. No guidelines exist and practitioners frequently rely on their own experience and preconceived information, which are not…
In 1977, gunshots caused 31,636 fatal injuries and 100,000 nonfatal injuries in the United States. The lifetime costs of treating all US gunshot wounds (GSW) in 1994 were $2.3 billion. The average medical cost of a…
Successful cataract surgery depends upon the latest techniques, state-of-the art instrumentation, and latest advances in viscoelastic technology. To maximize the benefits of the various available viscoelastics such as…
Herpes simplex keratitis consists of several common and potentially sight-threatening corneal conditions. Herpes simplex keratitis remains the leading cause of corneal blindness in the United States. Herpes simplex…
The history of PMMA intraocular lenses (IOLs) began with Harold Ridley in mid-twentieth century Britain. However, the idea of the IOL is considerably older and dates back to the beginning of modern cataract surgery.
Horner’s syndrome is an important clinical marker of potentially serious structural disease and results from disruption of the ocular sympathetic pathway. The three-neuron arc begins in the hypothalamus (first-order…
Although capsulorrhexis is the most important step of cataract surgery, hydrodissection is probably the most underrated. Hydrodissection produces a broad fluid wave that separates the epinucleus and the capsule. Nucleus…
Mild to moderate degrees of hyperopia can be successfully managed with currently available surgical techniques, including tissue removal procedures (e.g., photorefractive keratectomy [PRK] and laser in situ…
Hypotony is statistically defined as IOP of less than 10.1 mm Hg, which is 2 standard deviations below the mean population IOP of 15.9 mm Hg.1 Clinical hypotony occurs when ocular function is decreased secondary to…
Patients with orbital or central nervous system disease often present with symptoms of loss of vision or visual field, double vision, eye pain, and proptosis. These symptoms many times signal potentially life- or…
In this tutorial, we discuss the importance of objective vertex distance measurements in achieving the most accurate refractive surgical results.
Incisional burns may range in severity from mild collagen shrinkage to severe whitening with gaping of the wound (Slide 1). Thermal injuries appear to be more common with clear corneal incisions, either because mild…
It has been known that elevated intraocular pressure (IOP) is a significant risk factor for the development of glaucomatous optic neuropathy and visual field loss,1-5 and that reducing the IOP in patients at risk can…
An indication for explanting an intraocular lens (IOL) can occur either at the time of primary implantation or months to years later. An explantation is indicated when an IOL becomes damaged or malpositioned, or when…
Nelson: For this discussion, let us consider a case of infantile esotropia (Slide). A 4-month-old child presents with a history of his eyes turning in most of the time, since about 8 weeks of age. The child is healthy…
Inflammatory glaucoma encompasses a number of etiologies ranging from local ocular inflammation to ocular manifestations of systemic diseases. Despite the etiology of the inflammation, glaucoma develops from a common…
Half of infant homicides occur during the first 4 months of life1,2 and 80% of infant homicides are thought to represent infant child abuse. More than three children die each day in the United States as a result of…
The cornea, being the principal refractive element of the eye, has been the focus of the refractive surgeon’s attention in an attempt to correct refractive errors. Contemporary refractive surgical methodologies aimed at…
Interpseudophakos/interlenticular opacification (IPO/ILO) has emerged as a late complication of piggyback IOL implantation.1-4 IPO/ILO is characterized by ingrowth of lens epithelial cells (LECs) between the IOLs, 1 to…
Buttonhole flaps (Slide 1), especially thin flaps, are one of the more common LASIK flap-related intraoperative complications encountered, with incidence ranging from 0.1% to 0.2% depending on surgeon experience.1-6 In…
Involutional entropion and ectropion are malpositions of the lower eyelid, commonly encountered in clinical practice. This tutorial will discuss the etiology, symptoms, and differential diagnosis of these disorders, as…
Several measurements of the eye are helpful in determining the appropriate intraocular lens (IOL) power to achieve a desired refraction. These measurements include central corneal refractive power (keratometry…
In 1979, Eagle and colleagues1 proposed the term iridocorneal endothelial (ICE) syndrome to unify a group of disorders that share a number of clinical characteristics. Essential iris atrophy, Chandler’s syndrome, and…
A fourth nerve palsy is a relatively common cause for binocular diplopia in adults. History and examination are necessary to differentiate the common and benign etiologies from the potentially dangerous neurologic…
Juvenile open-angle glaucoma (JOAG) is a form of primary open-angle glaucoma affecting people early in life. JOAG is diagnosed in patients 3 to 20 years old. There is no known racial or sexual predilection. In the…
Keratoconus is a progressive disorder of noninflammatory corneal thinning in which the stroma assumes a conical shape, leading to myopia and irregular astigmatism, and mild-to-marked impairment in quality of vision.…
Clinical experience with photorefractive keratectomy (PRK) since its initial U.S. Food and Drug Administration (FDA) approval in 1995 has confirmed the safety and efficacy of the procedure in treating low to moderate…
Epiphora is defined as an abnormal overflow of tears down the cheek. This condition may be congenital or acquired.
The lacrimal gland is an exocrine gland, nestled within the lacrimal gland fossa of the frontal bone in the superotemporal orbit. The gland is subdivided anatomically, by the lateral horn of the levator aponeurosis,…
Peripheral iridectomy (PI) was introduced in 1956 but later gained popularity with the advent of argon laser and, more recently, with the neodymium:yttrium-aluminum-garnet (Nd:YAG) laser. Peripheral iridectomy involves…
Currently, lasers are used in the periorbital region to treat a wide spectrum of disorders. The following discussion will focus on cutaneous skin resurfacing, the most common laser application.
The word laser is an acronym for light amplification by stimulated emission of radiation. Lasers operate in the quantum world of atoms and photons. Three concepts involving the interaction between photons and atoms are…
Ophthalmic lasers are used to treat a variety of anterior segment disorders. The anterior segment tissues that can undergo laser treatment include the cornea, iris, trabecular meshwork (TM), lens capsule, and ciliary…
Dramatic improvements in microsurgical techniques have resulted in penetrating keratoplasty becoming a more common and successful procedure. It is unfortunate that postoperative visual rehabilitation remains…
Close attention to detail is crucial for a surgeon when performing laser in situ keratomileusis (LASIK). In this manner, the surgeon can anticipate and avoid potential complications. This discussion reviews the common…
Close attention to detail is crucial for a surgeon when performing laser in situ keratomileusis (LASIK). In this manner, the surgeon can anticipate and avoid potential complications. This discussion reviews the common…
Lattice corneal dystrophy is one of the classical stromal dystrophies marked by deposition of amyloid in the tissue. Lattice corneal dystrophy is autosomal dominant in its inheritance pattern, and typically bilateral.…
Modern phaco strategies seek to subdivide the nucleus into small maneuverable pieces. This "disassembly" of the nucleus has two advantages: (1) The 10-mm wide nucleus can be removed through an intact 5-mm capsulorhexis.…
The upper eyelid typically covers the superior cornea by 1 mm to 2 mm. Likewise, although there is individual variation, the lower eyelid typically sits just below the inferior corneal margin. The levator palpebrae…
Zonular compromise, whether congenital, iatrogenic, traumatic, or due to disease, presents a serious challenge to cataract surgeons. Every step of the surgical procedure from capsulotomy to final removal of the…
Introduction Macular holes are a relatively uncommon condition, estimated to occur in approximately 1 in 5,000 patients. Primary idiopathic macular hole is an age-related condition, typically affecting individuals in…
Cutaneous carcinoma is the most common malignancy in the United States. Approximately 500,000 people are treated annually for basal or squamous cell carcinoma of the skin. Approximately 5% to 9% of all skin cancers…
Modern cataract surgery has advanced to offer unprecedented patient benefits and has attained a level of successful outcomes where it may now be viewed as a refractive procedure. It is important to recognize, however,…
LASIK's success as a surgical means of correction of refractive error is due in part to the low complication rate associated with this procedure. Many of the complications associated with the procedure are associated…
Much of the data published on botulinum toxin type A (BTA) in the treatment of strabismus have been derived from retrospective or empirical studies of general strabismus populations and do not singularly evaluate a…
Cataract extraction with intraocular lens (IOL) implantation is a commonly used surgical procedure to manage pediatric cataracts. The anterior lens capsulotomy/capsulectomy is a critical surgical step of modern cataract…
The accumulation of blood in the anterior chamber is one of the most challenging clinical entities encountered by the ophthalmologist. Even a small hyphema can be a sign of major intraocular trauma with associated…
Porous orbital implants (e.g., hydroxyapatite, porous polyethylene, aluminum oxide) are commonly used during enucleation, evisceration, and secondary orbital implant surgery.1 The extensive pore systems permit…
The incidence of glaucoma after penetrating keratoplasty is concerning to the clinician. Increased intraocular pressure (IOP) can not only damage the optic nerve, but also compromise the function of the corneal graft.…
Mature white (cortical) and brown (nuclear) cataracts are challenging for many reasons. The capsulorhexis is difficult to visualize because of the lack of any red reflex and the liberation of cortical "milk" following…
Merkel cell carcinoma (MCC) is an aggressive neuroendocrine malignancy of epidermal origin with a natural history of local recurrence, lymph node metastasis, and distant dissemination.1,2 MCC is an uncommon skin…
Microphthalmos is a rare, potentially devastating condition occurring in 0.046% to 0.11% of patients in several large ophthalmic out-patient populations.1 Congenital microphthalmos can be either associated with coloboma…
Posterior lenticonus is a defect in the posterior lens capsule associated with cataracts.1 The defect of the posterior lens capsule is often a well-circumscribed, spheroidal, or conical protuberance of the posterior…
The form of optical correction chosen by an individual reflects his or her lifestyle including occupational and recreational needs. As such, a patient who is active in sports and outdoor activities that require…
A 60-year-old man was followed by the New England Eye Center glaucoma service since 1993. He was first seen by an ophthalmologist at the age of 18 months because he was noted to have "crossed eyes." Despite wearing…
Runge opened and obliterated the frontal sinus in 1750. Lanbeck first described the clinical presentation of frontal sinus mucoceles in 1818. In 1884, Ogston created a trephine hole through the anterior table and…
Mucous membrane pemphigoid (MMP) is a term first defined in 2002 (during the first international consensus on MMP) as "a heterogenous group of autoimmune, chronic inflammatory, subepithelial blistering diseases…
Multifocal intraocular lenses (IOLs) are designed to address both aphakia that is surgically induced during cataract surgery and the loss of accommodation that accompanies the use of monofocal IOLs. When inserted at the…
The wide use of lasers in ophthalmology has not escaped the field of cataract surgery. Now, surgeons can offer their patients cataract laser surgery. In June 2000, the U.S. Food and Drug Administration (FDA) approved…
Neovascular glaucoma (NVG) is historically known as rubeotic glaucoma, from the rubeosis iridis that refers to the iris neovascularization seen with this secondary glaucoma. The most common causes of NVG are ischemic…
Gorlin's syndrome, also known as nevoid basal cell carcinoma syndrome, is an inherited condition that affects many organ systems. Late in the course of this disease, a patient may present with multiple, aggressive basal…
New technology brings challenges and opportunities to the anterior segment surgeon. The drive toward less traumatic surgery and more rapid visual rehabilitation after cataract surgery has spawned various modalities for…
One of the most exciting advances in corneal transplant surgery is the development of lamellar techniques for replacing damaged or dysfunctional corneal endothelium. To put these new techniques in perspective, one must…
Anterior ischemic optic neuropathy is a common cause of acute unilateral vision loss with optic disc edema. Unlike optic neuritis, anterior ischemic optic neuropathy is typically painless. Anterior ischemic optic…
Normal-tension glaucoma (NTG) refers to glaucomatous optic nerve head changes and corresponding glaucomatous visual field defects in the absence of elevated IOP. Glaucoma without high IOP was first described by von…
Ocular ischemic syndrome (OIS) is a rare but important cause of blindness. It is a constellation of signs arising from a reduction in perfusion pressure to the globe (mean blood pressure minus intraocular pressure…
Neurologic, ophthalmologic, and systemic disorders with common chronic progressive external ophthalmoplegia (CPEO) have been identified. Chronic progressive external ophthalmoplegia may also occur in isolation of any…
The optic nerves exit the globe posteriorly and converge at the optic chiasm (Greek Χ chi). The visual fibers then diverge from the chiasm to form the optic tracts (Slide 1). The temporal fibers remain uncrossed and the…
Optic disc edema with a macular star (ODEMS) is a descriptive term for the ophthalmoscopic findings seen in a heterogeneous group of disorders. The clinical findings include swelling of the optic disc head, hard macular…
Optic neuritis refers to idiopathic or demyelinating optic neuropathy. A patient with optic neuritis typically is a young adult with acute, unilateral visual loss associated with eye movement pain. Childhood optic…
Accommodation allows the phakic eye to change focus from distant objects to closer objects. During accommodation, an interaction between the ciliary muscle and the crystalline lens allows the required optical power…
Contact lenses are made from a variety of polymers that can be separated into two broad categories: soft, or hydrogel, lenses and rigid lenses.
Light focused by the human eye is refracted by multiple curved surfaces before falling on the retina, where an electrical impulse is generated, eventually perceived as vision. The corneal tear film, corneal layers, and…
The implantation of intraocular lenses (IOLs) following removal of a cataractous crystalline lens is one of the most common surgical procedures performed in the United States. From an optical standpoint, the typical…
In the past decade, refractive surgery has become a widespread means for reducing refractive error in the adult population. The two most prevalent techniques are incisional surgeries, such as radial keratotomy (RK) and…
Lens extraction with the implantation of an IOL is the most commonly performed refractive procedure in the world today. Since the invention of the IOL by the late Sir Harold Ridley in 1949, lens implantation has been…
Lymphangioma is a rare, diffusely infiltrating, benign, nonencapsulated vascular tumor most commonly diagnosed in the first or second decade of life. Despite a congenital nature and low proliferative potential,…
Thyroid-related orbitopathy (TRO) is clinically relevant in approximately 50% of patients with Graves' disease. However, only 3% to 5% of patients develop serious complications that require surgical intervention. In…
The orbit is an important site for primary and secondary disease processes. Because the volume of the orbit is small, many of the presenting signs of orbital disease are ophthalmic. An understanding of the anatomy of…
The orbit of the eye comprises the globe with its muscles, blood vessels, lymphatics, cranial nerves 2, 3, 4, 5, and 6, sympathetic and parasympathetic nerves, adipose tissue, connective tissue, and the lacrimal…
Rhabdomyosarcoma is a malignant neoplasm composed of cells with histologic features of striated muscle tissue at various stages of embryogenesis.1 It develops from undifferentiated mesenchymal cells that possess the…
Orbital procedures can be overwhelming, even to the experienced orbital surgeon. Fortunately, advances in neuroimaging modalities, microsurgical techniques, and instrumentation have revolutionized the way we look at…
Thyroid-related orbitopathy is the most common cause of referral of patients with orbital disease. Other causes include neoplasia, structural, inflammatory, and vascular lesions.
More than 92,000 people in the United States are waiting to receive donated organs and/or tissues. The lack of anatomical gifts results in organ waiting lists that increase daily by one potential recipient every 13…
To fully understand the eyelid and orbital anatomy, a basic knowledge of the embryology of the eye and its adnexal structures is required. An important distinguishing feature in ocular development is the concept that…
Papilledema is a condition that is usually reflected in both eyes as bilateral disc edema. It is secondary to raised intracranial pressure (ICP), and often denotes a serious process. The cause of raised ICP cannot be…
Cancer produces neuro-ophthalmic manifestations through a variety of mechanisms including direct compressive effects from the primary lesion or metastatic disease, infiltration (e.g., carcinomatous or lymphomatous…
Since the introduction of corneal lamellar refractive surgery, complications unique to the creation of the flap have been a concern.1-5 Operative complications related to the lamellar flap include striae, epithelial…
In November 1998, the Staar (Monrovia, Calif) plate haptic toric IOL became the first toric lens approved by the U.S. Food and Drug Administration. Earlier and concurrent studies have suggested that the plate haptic…
Despite the continuing threat of amblyopia, in children, the prognosis for a good visual outcome after cataract surgery has improved dramatically over the past two decades. Not only has there been an increased…
Despite the continuing threat of amblyopia, in children, the prognosis for a good visual outcome after cataract surgery has improved dramatically over the past two decades. Not only has there been an increased…
Ophthalmologists frequently encounter disorders of the lacrimal system, particularly in infants and young children. Epiphora in the first year of life has been reported to occur in as many as 20% of children.1 Knowledge…
Acute conjunctivitis caused by IgE-mast cell-mediated reactions is the most common hypersensitivity response of a child's eye.1 An estimated 50 million mast cells reside at the interface of the conjunctiva.2 Direct…
Nelson: Once the diagnosis of strabismus is made, consent is given, the data are established, and it is clear the patient needs surgery, does your hospital require medical clearance and preoperative blood work?
Evidence of zonular laxity can be obtained preoperatively, during surgery but before phacoemulsification, or during nucleus and/or cortex removal.
Phacoemulsification surgery can be described based on its two fundamental components. First, ultrasound energy is used to emulsify the nucleus. Second, a fluidic circuit is used to remove the emulsate through a small…
All phacoemulsification machines consist of a computer to generate ultrasonic impulses, a transducer, and piezo electric crystals that turn these electronic signals into mechanical energy. The energy that is created is…
The treatment of high refractive error presents unique challenges to refractive surgeons. In keratorefractive surgery, the anterior corneal curvature is altered to change the conjugation point of the eye. However, a…
Photorefractive keratectomy (PRK) is a corneal-based refractive surgical procedure designed to reduce reliance on spectacles or contact lenses.1,2 PRK is approved by the Food and Drug Administration to treat all aspects…
Excimer laser phototherapeutic keratectomy (PTK) was approved by the U.S. Food and Drug Administration (FDA) in 1995 for the treatment of recurrent corneal erosions, irregular astigmatism, and elevated epithelial or…
Pigment dispersion syndrome (PDS) occurs when pigment from the posterior surface of the iris is liberated and deposited on intraocular structures of both eyes. The pigment can deposit on the corneal endothelium, the…
Primary angle-closure glaucoma occurs by pupillary block or plateau iris and is a common cause of angle-closure glaucoma in young people. Plateau iris configuration refers to anteriorly positioned ciliary body processes…
Mycobacterium chelonai is a rapidly growing nontuberculous mycobacterium omnipresent in soil, food, and tap and laboratory water.1-4 It is a member of the M. fortuitum complex that is also composed of M. fortuitum and…
The authors have no financial or proprietary interest in any product mentioned in this tutorial. Supported in part by an unrestricted grant from Research to Prevent Blindness, Inc, New York, NY.
Cystoid macular edema (CME) is a disease entity that has been studied in ophthalmic literature. CME is a disruption of the blood-retinal barrier that leads to the accumulation of fluid in the retinal extracellular space…
Postoperative endophthalmitis is a rare but potentially devastating complication of cataract surgery. Postoperative endophthalmitis can be either sterile or infectious. Sterile endophthalmitis is also known as the toxic…
Clinician-patient communication is important to ensure a satisfactory outcome for refractive surgery. Clinicians can educate and counsel patients regarding alternatives to refractive surgery, as well as the risks and…
A well-centered posterior chamber IOL is the anatomic goal of every cataract surgery. Good centration is best assured by in-the-bag placement of both haptics and a capsulorrhexis sized slightly smaller than the optic…
Worldwide, glaucoma is the second leading cause of blindness. Estimates have been made demonstrating that one-half of the 67 million people diagnosed with glaucoma have primary angle-closure glaucoma (PACG). In…
Myopia affects approximately 25% of adults in the United States. Approximately 10% of the myopic population can be expected to have visually significant astigmatism of more than 1 D. With recent technological advances,…
The term prion disease refers to a group of fatal neurodegenerative disorders for which no treatment or cure is available. With the emergence of variant Creutzfeldt-Jakob disease (CJD) in the past decade,…
Light passing through a flat (planar) interface between media of different refractive indices is refracted without change of vergence. At a curved surface, vergence would be altered. If an optical medium is limited by…
Retinoblastoma is the most common primary intraocular malignant tumor in children with an incidence of 1 in 15,000 live births.1 The average annual incidence of retinoblastoma in the United States has been estimated at…
With age, people become presbyopic (i.e., experience loss in power of accomodation). Reading small print, performing operations on small objects, or working with detailed technical drawings may become difficult. Reading…
Retained posterior nuclear fragments greatly increase the risk of postoperative complications and must usually be retrieved through a subsequent three-port vitrectomy. Therefore, the diagnosis and management of…
For the past 50 years, ophthalmic surgeons have witnessed enormous breakthroughs in the treatment of many ocular diseases and disorders, especially in the field of cataract surgery and its ability to correct preexisting…
Before the advent of small-incision cataract surgery, a primary goal of cataract surgery was the prevention and postoperative management of unwanted corneal astigmatism. With the introduction of astigmatically neutral,…
In 1985, 76% of the members of the American Society of Cataract and Refractive Surgeons (ASCRS), responding to an annual survey, indicated a preference for retrobulbar anesthesia with a supplemental facial nerve block…
With early intracapsular surgical procedures, ophthalmologists purposefully created large superior sector defects. Often, iris tissue became incarcerated in a corneal or scleral wound, thereby, creating marked…
Retinal arterial macroaneuryms (RAMs) are acquired vascular dilatations located mainly at the arterial bifurcations on the first three orders of the arterial tree (Slide 1A and Slide 1B). RAMs occur most commonly in…
Disorders commonly associated with these mechanisms include hypertension, diabetes, atherosclerosis, and diseased cardiac valves. In patients younger than 30, other disorders are more significant, including migraine,…
The increased risk of developing rhegmatogenous retinal detachment (RRD) following cataract extraction is well recognized. With the evolution of cataract surgery from intracapsular, aphakic techniques to extracapsular…
Although ocular exposure to light is an obvious necessity for sight, it has been implicated as a causative element in a host of disorders of the human eye, involving structures including the cornea and ocular surface,…
Meyer-Schwickerath has been credited with early attempts at retinal photocoagulation; first with sunlight in 1946, then with his development of the xenon-arc lamp in 1956.1 The first ophthalmic laser was developed by…
Retinoscopy is an objective method of determining a patient's refractive error. Although some degree of patient cooperation is needed, no subjective responses from the patient are necessary. The accuracy of the…
Amblyopia is a common cause of decreased vision in children and young adults.1-4 The prevalence of amblyopia varies from 0.2% to 5.3% depending on the population that is evaluated.1 Amblyopia is often unilateral, but…
Refractive surgery has been steadily increasing in popularity over the past decade. Advances in technology and improvements in techniques have led to improved clinical outcomes. In turn, this has led to higher patient…
Supported in part by an unrestricted research grant from Research to Prevent Blindness, Inc., New York, New York
In 1993, my colleagues and I first described the implantation of two intraocular lenses (IOLs) in the eye, piggybacking, to provide adequate power in a case of microphthalmos.1 Since then, piggybacking IOLs has become…
A sixth nerve palsy is a common cause for binocular horizontal diplopia in adults. A complete history and examination are necessary to differentiate the common and benign etiologies from the potentially dangerous…
The phaco chop technique was a revolutionary addition to the advancement of cataract surgery. However, one difficulty with the technique was the creation of the intracapsular jigsaw puzzle and the limitation of…
Multiple factors are involved in the relationship between strabismus and refractive error. Ophthalmologists are familiar with the dynamics of hypermetropia producing accommodative esotropia. However, few are cognizant…
Successful strabismus surgery depends on a thorough knowledge of the anatomy of the extraocular muscles and fascia. Average values for the anatomic insertions, tendon and muscle lengths, and the relative positions of…
Sturge-Weber syndrome is one of several syndromes classified under the heading of phakomatosis because it involves pathology in the skin, eye, and brain. The first reported description of Sturge-Weber syndrome…
Accuracy in objective refraction (retinoscopy) relies on the retinoscopist's abilities or the autorefractor's software. However, subjective refraction involves complex interaction between a refractionist and a patient…
To ensure that accommodation does not degrade the results of refraction, it is sometimes necessary to eliminate the patient’s ability to accommodate, albeit temporarily. Cycloplegic eye drops provide an anticholinergic…
Accuracy in objective refraction (retinoscopy) relies on the retinoscopist's abilities or the autorefractor's software. However, subjective refraction involves complex interaction between a refractionist and a patient…
To ensure that accommodation does not degrade the results of refraction, it is sometimes necessary to eliminate the patient’s ability to accommodate, albeit temporarily. Cycloplegic eye drops provide an anticholinergic…
Superior limbic keratoconjunctivitis (SLK) is a disease characterized by inflammation of the upper palpebral and superior bulbar conjunctiva.1 Secondary epidermalization of the superior limbal conjunctiva with keratin…
Intraoperative suprachoroidal hemorrhage and the consequential expulsive hemorrhage that can occur constitute the most serious complication in ocular surgery. The conversion to phacoemulsification has decreased the…
In the Eyelid Retraction tutorial, a differential diagnosis was enumerated. In clinical practice, the most common entities related to upper eyelid retraction are:
IOL implantation is an effective form of visual rehabilitation at the time of cataract extraction. However, IOLs also benefit patients who originally underwent cataract extraction without a lens implant and are now…
Hydroexpression with an irrigating vectis is a simple technique of sutureless extracapsular cataract extraction (ECCE) using a combination of mechanical and hydrostatic forces to express out the nucleus.1 An irrigating…
Sympathetic ophthalmia is a rare, bilateral inflammatory process involving the uveal tract occurring secondary to penetrating trauma or ocular surgery. It is characterized by an insidious onset followed by a chronic,…
Temporal arteritis, also known as giant cell arteritis or cranial arteritis, is a vasculitis that affects the arteries of the head and neck. The mean age at presentation is 70 years. White women are affected somewhat…
A brunescent nucleus challenges every phacoemulsification surgeon. Successful management of a rock-hard cataract requires that each surgeon first understand and then use specific strategies to overcome these…
The search for the ideal orbital implant began in 1885 when Mules placed a glass spherical implant into an eviscerated socket. One year later, Frost introduced a similar implant into Tenon's capsule following an…
Presbyopia Accommodation is the process that allows the human crystalline lens to change its focus from far to intermediate or near vision. With age, the crystalline lens loses its ability to focus on near objects,…
It is a truism that, "If you operate, you will have complications." Wise surgeons plan ahead to avoid complications and to manage those that unavoidably occur. Also a truism - clinicians who prescribe glasses will have…
Refractive surgery over the past decade has been the fastest-growing segment of the ophthalmic market. Clinicians continue to gain greater experience with the current technology and procedures even as new innovations…
Excimer lasers used in photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) emit a wavelength of 193 nm.1 The concerns over these ultraviolet (UV) laser systems include high investment and…
An anterior capsulotomy is the capsular incision necessary to allow removal of the nucleus and cortex. It should be capable of preserving the integrity of the capsular bag against the asymmetric forces that occur during…
The evaluation and management of isolated and unexplained optic atrophy is a relatively common, but difficult, clinical problem for a comprehensive ophthalmologist. Although, in most cases, the history and examination…
The four quadrant divide and conquer phacoemulsification procedure (Slide 1), or in situ fracture as I originally named it, was first performed in 1988. This tutorial discusses the origination and the steps of the four…
Cataract surgery is considered to be the premier surgery for ophthalmic surgeons. With declining interest in refractive surgery, ophthalmic surgeons are now faced with cataract surgery in the baby-boomer generation.…
By optical coherence biometry (OCB), axial length measurements with the IOLMaster are the equivalent of upright, ultra-high-resolution immersion A-scan ultrasonography, approximately five times more accurate than…
In the United States, approximately 4 million people have Sjögren's syndrome, which is a systemic autoimmune disease that involves signature symptoms of dry eye (keratoconjunctivitis sicca [KCS]) and dry mouth.1 It has…
What differentiates the cornea from materials such as a contact lens? The cornea is an elastic collagen lamellar structure, the curvature of which is maintained firmly and constant by IOP. It is not difficult to imagine…
Performance of a successful eye examination in an infant or young child requires flexibility in approach and a willingness to modify the sequence of the examination when required. Often faced with minimal historic…
The increased acceptance of topical anesthesia, phacoemulsification, and small foldable IOLs has prompted the development of clear corneal cataract surgery techniques.1 Operating through small corneal incisions that are…
Vision is the perception of light. To comprehend the nature of human vision, an understanding of the properties of light is necessary. Many of the technologies used for examining the eye and treating ocular disease take…
The size of the pupillary aperture is controlled by two opposing smooth muscles, the dilator and the sphincter. The dilator muscle originates at the iris root and lies within the cytoplasm of the anterior portion of the…
Modern cataract surgery performed with phacoemulsification allows meticulous intraocular control and minimal incision size. However, inherent risks of capsular rupture exist. Therefore, surgeons performing cataract…
LASIK has become the most commonly performed surgical procedure for the correction of refractive error. Limitations to LASIK exist, especially in higher refractive errors in which patients can experience reduced…
Despite new developments in antimicrobial agents, a subgroup of bacteria, fungi, parasites, and viruses that does not respond to medical therapy remains.1-7 Therapeutic keratoplasty is indicated when inflammatory or…
A patient presenting with a third nerve palsy is considered one of the "highest stakes" encountered by an ophthalmologist. On one hand, a patient may have an isolated, vasculopathic third nerve palsy that resolves with…
Dry eye is a common condition seen in patients with autoimmune disease, women who are postmenopausal, and the elderly.1,2 In a population-based prevalence study of people 65 years of age or older, 14.6% of 2,482…
The term traumatic glaucoma incorporates a variety of posttraumatic mechanisms that lead to a rise in IOP. Traumatic glaucoma often occurs from a blunt injury that causes anterior segment deformation during impact, but…
Any patient with a disorder of afferent visual function after trauma, characterized by loss of visual acuity, color perception, visual field defect, or loss of contrast sensitivity in one or two eyes, should be…
Retinoblastoma is the most common malignant intraocular tumor in children,1 occurring in approximately 1 of 23,000 live births.2 For many years, the conventional treatment of retinoblastoma was primary enucleation.3…
The presence of vitreous gel in the anterior chamber is associated with an increased risk of serious intraoperative and postoperative complications. It is fortunate that the incidence of many vision-threatening…
Various nontoxic ophthalmic dyes have been extensively used as diagnostic agents for the detection and management of different ocular disorders. Table 1 summarizes the use of various dyes in ophthalmology. Dyes such as…
At the start of the new millennium, the world of ophthalmology hailed a celebration of its own: the 50th anniversary of Sir Harold Ridley's original IOL implant. More recently, a lesser but significant revolution has…
The measurement of visual acuity enables physicians to communicate with the patient, as well as other physicians, the level of preservation or degradation of vision. Visual acuity serves as a report card for the…
The visual afferent neural pathway begins in the retina (e.g., photoreceptors, retinal ganglion cells, nerve fiber layer) and travels in the ipsilateral optic nerve. At the optic chiasm, the nasal fibers cross and the…
Before the advent of wavefront technologies, refractive error was measured by only three parameters: sphere, cylinder, and axis. Wavefront analysis has facilitated the evaluation of the eye's entire refractive status to…
Wegener's granulomatosis is characterized by necrotizing granulomatosis lesions of the respiratory tract, glomerulonephritis, and vasculitis.1 However, Wegener's granulomatosis can affect almost any organ system, as its…
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