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Importance: Schnabel cavernous degeneration (SCD) has been observed in eyes with uveal melanoma (UM), but, to our knowledge, a definitive study establishing the association between SCD and UM has not been conducted., Objective: To explore an association between SCD and UM., Design, Setting, and Participants: A historical cohort analysis was performed using histologic slides and related clinical records of cases from the Collaborative Ocular Melanoma Study and Eye Pathology Laboratory at the University of Wisconsin, including 1985 UM eyes, 517 eye bank eyes, and 155 enucleated glaucomatous eyes., Main Outcomes and Measures: The prevalence of SCD was calculated and compared between each group; subgroup analysis was also conducted of eyes with and without SCD for the prevalence of glaucoma., Results: Schnabel cavernous degeneration was seen in 17 (0.9%) UM eyes, 9 (1.7%) eye bank eyes, and 2 (1.3%) enucleated glaucomatous eyes. No difference was detected between the prevalence of SCD in UM eyes and eye bank eyes (odds ratio [OR], 0.49; 95% CI, 0.22-1.10) or enucleated glaucomatous eyes (OR, 0.66; 95% CI, 0.15-2.89). Subgroup analysis, performed on 421 UM eyes, provided sufficient clinical information to definitively establish the presence or absence of glaucoma. Of the 95 (22.6%) eyes with glaucoma, 11 (11.6%) revealed histopathologic evidence of SCD. Compared with enucleated end-stage glaucoma eyes, this represents a 10-fold increase in SCD in UM eyes with glaucoma (OR, 10.10; 95% CI, 2.17-46.26). The prevalence of glaucoma in UM eyes with SCD, however, was respectively 7- and 15-fold higher than the prevalence of glaucoma in SCD-negative UM eyes (OR, 6.98; 95% CI, 2.51-19.43) and SCD-positive eye bank eyes (OR, 14.67; 95% CI, 1.46-146.97)., Conclusions and Relevance: Although an association between SCD and UM was not confirmed, subgroup analysis did reveal an increased incidence of SCD in eyes with both UM and glaucoma. This suggests that the occurrence of glaucoma may increase the risk of SCD in eyes with UM.

Objectives: To examine the histopathologic features of iridectomy specimens from patients undergoing glaucoma surgery and to compare histologic abnormalities in a group of patients with a history of latanoprost therapy with those in a group of patients who had no history of prostaglandin therapy (controls)., Methods: Iridectomy specimens and patient history forms were submitted to the central Latanoprost Pathology Center. These were independently examined by 3 ophthalmic pathologists in a masked fashion. Specimens were evaluated for malignant, premalignant, and other changes including differences in levels of pigmentation, degrees of cellularity, inflammation, vascular abnormalities, and changes in the iris pigment epithelium., Results: Specimens were received from 449 patients with a history of latanoprost treatment and 142 patients who had no history of treatment with latanoprost or other prostaglandin analogues. No evidence of malignant or premalignant changes was found. In latanoprost-treated irides, the prevalence of iris freckles was higher (P = .001) than in control irides, as was the combined number of stromal fibroblasts and melanocytes (P<.001). In a subgroup of specimens received through June 2002, there was no significant difference in mean melanocyte counts (P=.35) obtained by immunohistochemical staining techniques between the latanoprost-treated and control groups., Conclusions: These findings support previous studies indicating that latanoprost-induced eye color changes are due to an increased amount of melanin within the iris stromal melanocytes. The increased numbers of freckles may be a focal manifestation of this effect.

Objective To examine structural changes and aqueous humor outflow after viscocanalostomy in live normal monkey eyes. Methods Viscocanalostomy surgery was performed in 1 eye of each of 4 rhesus monkeys. Outflow facility was determined before and after surgery. All eyes were fixed and examined by light and/or electron microscopy 36 or 63 days postoperatively. Results Schlemm canal was replaced by scar tissue at the surgical site. The juxtacanalicular zone contained homogeneous material, probably high-molecular-weight 1.4% sodium hyaluronate. The sclera external to Schlemm canal was overhydrated, and remains of a scleral lake were present in 1 animal. Multiple defects were present in the endothelial lining of Schlemm canal inner and outer wall. Fine fibrillar material and sheath-derived plaque material partly bridged the defects. Along the inner wall, aggregations of thrombocytes covered some defects in the endothelial lining of the canal. At 90° to 180° from the surgical site, small and fewer breaks in the inner wall were seen. Postsurgery outflow facility (n = 2) was approximately 30% higher in the treated eye than in the contralateral control, corrected bilaterally for presurgery baseline. Conclusions The most likely explanations for the increase in outflow facility in monkeys after viscocanalostomy are focal disruptions of the inner wall endothelium of Schlemm canal and disorganization of the juxtacanalicular zone, resulting in direct communication of juxtacanalicular zone extracellular spaces with the lumen of Schlemm canal. The continuous presence of sodium hyaluronate might prevent repair of these defects by interfering with thrombocyte function. Clinical Relevance In nonhuman primates, viscocanalostomy appears to decrease outflow resistance through persisting focal disruption of the inner wall endothelium and opening of the juxtacanalicular or cribriform region of the trabecular meshwork, the tissue most affected by pathologic changes in primary open-angle glaucoma in humans. [ABSTRACT FROM AUTHOR]

Latanoprost, a selective FP prostanoid receptor agonist used in the treatment of glaucoma, has a hypertrichotic side effect. Using the macaque model of androgenetic alopecia, we examined the effect of latanoprost on hair growth. Eight monkeys were divided into 2 groups; one group received a daily topical application of 50 μg/ml of latanoprost for 5 months; a control group had a daily application of vehicle. For an additional 3 months, 2 monkeys from each group were given 500 μg/ml latanoprost, while the remaining monkeys continued with the previous treatment. Hair growth was evaluated by monthly photographs and phototricho-graphic analysis. Fifty μg/ml of latanoprost caused minimal hair growth. Latanoprost at 500 μg/ml induced moderate to marked hair regrowth with 5-10% conversion of vellus hairs to intermediary or terminal hairs. The vehicle group showed no effect. Further evaluation of latanoprost as an agent for treatment of human androgenetic alopecia is indicated. [ABSTRACT FROM AUTHOR]

Latanoprost, used clinically in the treatment of glaucoma, induces growth of lashes and ancillary hairs around the eyelids. Manifestations include greater thickness and length of lashes, additional lash rows, conversion of vellus to terminal hairs in canthal areas as well as in regions adjacent to lash rows. In conjunction with increased growth, increased pigmentation occurs. Vellus hairs of the lower eyelids also undergo increased growth and pigmentation. Brief latanoprost therapy for 2–17 days (3–25.5 μg total dosage) induced findings comparable to chronic therapy in five patients. Latanoprost reversed alopecia of the eyelashes in one patient. Laboratory experiments with latanoprost have demonstrated stimulation of hair growth in mice and in the balding scalp of the stumptailed macaque, a primate that demonstrates androgenetic alopecia. The increased number of visible lashes is consistent with the ability of latanoprost to induce anagen (the growth phase) in telogen (resting) follicles while inducing hypertrophic changes in the involved follicles. The increased length of lashes is consistent with the ability of latanoprost to prolong the anagen phase of the hair cycle. Correlation with laboratory studies suggests that initiation and completion of latanoprost hair growth effects occur very early in anagen and the likely target is the dermal papilla. [Copyright &y& Elsevier]

The new glaucoma drugs latanoprost, isopropyl unoprostone, travoprost, and bimatoprost cause increased pigmentation of the iris in some patients. The purpose of the present article is to survey the available preclinical and clinical data on prostaglandin-induced iris pigmentation and to assess the phenomenon from a clinical perspective. Most of the data have been obtained with latanoprost, and it appears that there is a predisposition to latanoprost-induced iris pigmentation in individuals with hazel or heterochromic eye color. As latanoprost and travoprost are selective agonists for the prostaglandin F2α receptor, it is likely that the phenomenon is mediated by this receptor. Several studies indicate that latanoprost stimulates melanogenesis in iridial melanocytes, and transcription of the tyrosinase gene is upregulated. The safety aspects of latanoprost-induced iris pigmentation have been addressed in histopathologic studies, and no evidence of harmful consequences of the side effect has been found. Although a final assessment of the clinical significance of prostaglandin-induced iris pigmentation currently is impossible to make, it appears that the only clear-cut disadvantage is a potential heterochromia between the eyes in unilaterally treated patients because the heterochromia is likely to be permanent, or very slowly reversible. [Copyright &y& Elsevier]