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Objective To evaluate the mydriatic effect of tropicamide eyedrops as a diagnostic test for Alzheimer's disease. Material and Methods In a double-blind, placebo-controlled study, we assessed pupillary responses in 22 normal control subjects, 23 patients with probable Alzheimer's disease, 4 patients with isolated memory difficulty, and 6 patients with nonAlzheimer's dementia. Three separate studies were performed, the second and third on a subset of the original group. With use of infrared binocular pupillography, after 5 minutes of dark adaptation, we averaged pupil size during a 1-minute interval for baseline determinations. We then instilled 0.01 % tropicamide into one eye. In the first two studies, we averaged pupil size for a 1-minute period at 5-minute intervals for 30 minutes, followed by a pupil light reflex test. In the third study, we measured pupil size every 5 minutes for 45 minutes and omitted the light reflex test. Results No significant difference was noted in pupil dilatation between normal subjects and patients with Alzheimer's disease and between patients with non-Alzheimer's dementias and the Alzheimer's disease group in all three studies. Furthermore, on reperformance of the test in the same patients, more than 50% changed from a group above or below 13% pupil dilatation (a cutoff reported to distinguish Alzheimer's disease from normal control subjects) to the opposite group. Conclusion Results of this study indicate that pupil measurement after instillation of tropicamide cannot be used as a reliable diagnostic test for Alzheimer's disease. Moreover, test-retest reliability with use of dilute tropicamide eyedrops is questionable.

Important concepts about glaucoma have evolved during the past few decades. Glaucoma is a family of diseases not defined by a specific intraocular pressure but rather as an optic neuropathy that can occur at any intraocular pressure depending on the optic nerve susceptibility of the individual person. Increased risk factors for idiopathic open-angle glaucoma include advancing age, black race, a family history of glaucoma, and increased intraocular pressure. The primary-care physician is in the prominent position of recognizing patients with increased risk factors or suspicious eye findings who should be referred to an ophthalmologist. Topically applied ophthalmic medications have systemic side effects that must be recognized and monitored by the primary-care physician. In the United States, glaucoma is usually treated with topically applied medications; laser or surgical therapy is done if medical treatment fails. The National Eye Institute is conducting multicenter studies to confirm whether this is still the most appropriate strategy for this common disease.

Ocular adnexal lymphoproliferative lesions consist of a spectrum of disease entities, including reactive lymphoid hyperplasia, atypical lymphoid hyperplasia, and lymphoma. No clinical or radiologic criteria facilitate a distinction among these lymphoproliferative lesions. The two hyperplastic processes may evolve to localized or systemic lymphoma. A similar pattern is evident in other mucosa-associated lymphoid tumors elsewhere in the body. Most ocular adnexal lymphomas are small lymphocytic non-Hodgkin's tumors with an indolent course; frequently, they remain localized to the ocular adnexa. In comparison, intermediate- and high-grade lymphomas are less common in the ocular adnexa but more aggressive. An approach to the diagnosis and treatment of these complex entities is suggested. Despite new pathologic classification schemes, immunophenotypic labeling, and molecular genetic analysis, the prognosis for patients with small-cell lymphoma in the ocular adnexa is difficult to predict.

Herpes zoster is a cause of considerable morbidity, especially among elderly patients, with a suggestion of a slight increase in incidence among female patients. Substantial research on the biology of the varicella zoster virus has led to advances in our knowledge of the pathophysiology of the disease along with more successful therapy for the acute episodes of herpes zoster. Ophthalmic zoster is more common than zoster in other cranial nerves and is associated with pronounced suffering. This article reviews the epidemiology, biology, and latency of herpes zoster, discusses the pathophysiology of the disease, and describes treatment options with antivirals and corticosteroids. The pathophysiology and treatment options for postherpetic neuralgia are also addressed. The varicella vaccine is now available, and initial results suggest that this may lessen the effect of herpes zoster in the future.

The rationale for prophylactic antibiotics in cataract operations must be continually reevaluated in light of cost-effectiveness and adverse reactions. The principles learned from wound infections associated with general surgical procedures should be applied to the limited knowledge about the rare event of endophthalmitis. Herein the literature on experimental and clinical wound infections in general surgical procedures is reviewed, with analysis of microbial flora, pathophysiology of wound infections, and pharmacokinetics of antibiotics. Experimental and clinical studies on prophylactic antibiotics to prevent endophthalmitis are reviewed, including information on topically applied antibiotics, chemical antisepsis, and administration of subconjunctival, intracameral, and systemic antibiotics. In addition, the benefits, limitations, and risks of the various types of prophylactic antibiotics are discussed. Because of the limited data on prophylactic antibiotics in cataract operations, providing dogmatic statements is difficult. General recommendations are offered based on the currently available literature, and a stratified approach is suggested based on wound construction and number of anterior segment maneuvers.

Objective The multiple causes of pigmentations of the conjunctiva and sclera are reviewed, and the recommended therapeutic modalities are discussed. Design Information from personal experience and the recent literature is summarized to determine the optimal diagnostic and treatment approaches for suspicious pigmented conjunctival and scleral lesions. Material and Methods Clinical descriptions and illustrations are presented to characterize these ocular lesions. Results Pigmented lesions of the conjunctiva and sclera arise from either melanocytes or nonmelanocytes and have a diverse differential diagnosis. These lesions can be classified into congenital melanosis, conjunctival nevi, acquired melanosis (secondary or primary), and conjunctival melanomas. In secondary acquired melanosis, the increased conjunctival pigmentation is caused by irradiation, hormonal changes, chemical irritation, or chronic inflammatory conjunctival disorders. The biologic behavior of primary acquired melanosis of the conjunctiva is a controversial topic with important implications because it may progress to melanoma. In patients with primary acquired melanosis, a biopsy is recommended in order to grade the disease, offer a prognosis, and direct further treatment. Conjunctival melanomas may arise from primary acquired melanosis, from nevi, or de novo, or they may be metastatic lesions. Conclusion Of the wide spectrum of melanocytic conjunctival lesions, those with malignant potential are melanosis oculi, nevus of Ota, junctional nevus, compound nevus, primary acquired melanosis, and melanomas.

Because of the frequent occurrence of cataracts in the general population, the surgical techniques for their removal and the potential associated complications are of widespread interest. The approaches available in general and those used at the Mayo Clinic are described.

Cataract operations are commonly performed in either a primary-care or a tertiary-care center. A plethora of information (some of which is unfounded) has been disseminated in the lay news media about the advances in the surgical techniques of cataract removal. This article reviews some of the recent concepts about the formation of cataracts and the modern approaches for their extraction. It is directed at the nonophthalmologic primary-care physician who refers patients for evaluation or performs the ancillary tests in preparation for a cataract operation. Space limitations prevent a complete review of the subject. Some of the controversial aspects of cataract surgical procedures are addressed objectively, but bias is unavoidable.

Ocular herpes simplex disease has a variable pattern of manifestations and recurrences as a result of the site and extent of the infection, the host immunologic events, the trophic damage within ocular tissues, and the toxic effects of antiviral medications. Laboratory research has established a clinical model and a working hypothesis about the complex pathophysiologic features of the disease and the interaction of the virus with its host tissue. Recent studies have further defined the viral genome and its role in virulence and pathogenicity. Antiviral therapy is effective in some but not all aspects of the ocular infection. A proposed clinical classification of ocular herpes simplex is based on the manifestations associated with viral disease and those associated with the host response and the subsequent structural damage. A plan for medical and surgical management of ocular herpes simplex, based on current knowledge of the disease process, relates to the integrity of the epithelium and the presence of active viral disease.