Abstract : Forty-two eyes in which there were residual retinoblastomas following radiotherapy were examined histopathologically. Forty percent of the tumors showed areas of photoreceptor differentiation. Three histopathologic patterns were noted. Some tumor nodules consisted entirely of cells showing photoreceptor differentiation while other tumor nodules consisted of cells mingled with glial cells or undifferentiated retinoblastoma cells. Detailed clinical descriptions before and after radiation therapy were available on four of the tumor nodules. These tumor nodules were described as grayish, translucent, or 'fish flesh' in appearance. In the follow up of 13 patients, only 1 tumor death was recorded. This study suggests that, while the tumors with photoreceptor differentiation are relatively benign histopathologically, they are comparatively resistant to radiotherapy.
Morphologic changes characteristic of mild and severe cell injury produced in retinal photoreceptors by a xenon arc coagulator were studied by light and electron microscopy. Mild or reactive cell changes consisting of a tubulovesicular rearrangement or breakdown of cell membranes differed considerably from the production of myriad focal densifications of cell membranes and associated ground substances occurring in the severe injuries. The latter alterations are considered to beirreversible and, therefore, a characteristic of necrosis.
Aging rhesus monkeys, both controls and those undergoing long-term administration of investigational oral contraceptive steroids, developed widespread hyperfluorescent dots at the posterior pole. The dots were considered to represent drusen. Histologic (including electron microscopic) study showed the "drusen" in some of the animals to be almost exclusively pigment epithelial windows produced by a lipoidal degeneration of the pigment epithelial cells. The experiment provided a fortuitous model for direct correlation of clinical and histologic observations of myriad uniform, tiny, depigmented, hyperfluorescent, nonleaking spots at the level of the retinal pigment epithelium.
Ever since the days of Leber1ophthalmologists have recognized the occurrence of fungal infections of the eye. Until recently, the major emphasis has been on corneal mycoses.2-5Relatively few cases of mycotic endophthalmitis have been reported (Cogan;6Fine and Zimmerman;7,8Harley and Mishler9). In part this might be explained by the low index of suspicion shared, in the past, by clinicians and pathologists and by the difficulty in histopathologic diagnosis when only routine staining techniques were used. During recent years the availability of a number of good differential stains which facilitate the microscopic recognition of fungi in tissue sections, coupled with an increased awareness by most pathologists of fungus infections, has resulted in an increasing number of cases of mycotic endophthalmitis diagnosed by histopathologic means. To date, such infections have almost invariably led to enucleation because clinical diagnosis and therapy are so very difficult. For
A 38-year-old man with a history of ocular melanoma was admitted for abdominal and back discomfort of 5 months duration. Four years prior, the patient was diagnosed with unilateral choroidal melanoma and treated with enucleation only. At that time, a single liver lesion was identified as an atypical hemangioma via percutaneous biopsy. The patient underwent serial hepatic imaging when a second and third mass were identified and presumed benign without repeat biopsy. The patient's craniocaudal liver span had been stable at 13 cm until 6 months prior to admission. At the time of presentation to our institution, physical exam revealed tender hepatomegaly with an unidentifiable liver edge, though the liver could be precussed into the right lower quadrant. Laboratory tests were notable for elevated alkaline phosphatase (146 U/L) and AST (175 U/L) with a normal ALT and bilirubins. AFP was within normal limits. Abdominal MRI revealed multiple heterogeneous masses within an enlarged and diffusely fatty liver, with a dominant mass replacing the entire right hepatic lobe measuring 15.5 × 15.0 × 18.2 cm. The liver measured a total of 31 cm craniocaudally (Figure 1). There was vascular compromise of the IVC. Osseous, pulmonary and renal metastases were also found. Biopsy of the hepatic masses identified hepatic tissue replaced by neoplastic cells arranged in clusters and sheets (Figure 2). The cells were large and heavily pigmented with hyperchromatic, pleomorphic, peripherally located nuclei with numerous intranuclear inclusions. Immunohistochemical markers including Melan-A, HMB-45, S100 and tyrosinase were strongly positive in this case (Figure 3). The patient was diagnosed with metastatic melanoma and referred to oncology. Ocular melanoma is a rare, affecting 6 per million individuals per year with a median age of onset of 60 years. Mutations in GNA11 or GNAQ, which encode the α subunit of G proteins, are strongly associated with uveal melanoma. Ocular melanoma metastasizes hematogenously; hepatic metastases are present at diagnosis in 40–60% of patients. Because of the strong propensity for hepatic metastasis, regular hepatic surveillance is important after eradication of the ocular tumor. Semi-annual screening with abdominal ultrasound and LFT's would detect > 95% of patients while they are asymptomatic. No tumor markers are available to identify recurrence of disease. Average survival after diagnosis of liver metastases is 15 months. Characteristics associated with a more favorable prognosis included the absence of ciliary body involvement of the primary tumor and the presence of fewer than 10 metastases at time of hepatic involvement. Management options are palliative including surgical resection, cytoreductive surgery, intra-arterial chemoembolization, immunoembolization, and systemic chemotherapy. Contributed by
A review of over 1,000 cataract operations performed over a two year period resulted in an approximately balanced indication for spectacles, daily wear contact lenses, and intraocular lenses.However, following 3% of the cataract procedures, an extended wear lens was required.The reasons for this selective need for extended wear, when other modalities for visual rehabilitation are available, is discussed.The practical importance of a limited but necessary use of extended wear lenses is reviewed.
