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Solitary fibrous tumor of the orbit

We report three cases of an orbital soft tissue lesion that fulfills the histologic, immunohistochemical, and electron microscopic criteria for solitary fibrous tumor, an entity previously described as a pleural tumor, but recently reported to occur in other locations. All three patients presented with proptosis. Two of the patients were cured by simple excision, and one patient had two recurrences, the last recurrence incompletely excised. The findings indicate that solitary fibrous tumor can occur in the orbit and, like solitary fibrous tumors of other anatomic sites, may behave in a nonaggressive or occasionally, locally aggressive fashion, with as yet no metastatic potential demonstrated in orbital lesions.

Neurofibromatosis and neural crest neoplasms: Primary acquired melanosis and malignant melanoma of the conjunctiva

With an occurrence of approximately 1 in 3000 births, von Recklinghausen neurofibromatosis (NF) is one of the most common inherited human disorders. NF is considered a neurocristopathy, a disorder of neural crest derived cells. One of the complications of NF is the development of neural crest derived malignancies such as malignant schwannoma, pheochromocytoma, and malignant melanoma of the skin and choroid. The case history of a patient with NF and conjunctival malignant melanoma which developed in an eye with primary acquired melanosis is yet another example of a neural crest malignancy developing in a NF patient.

Olivopontocerebellar Atrophy with Retinal Degeneration: An Electroretinographic and Histopathologic Investigation

BACKGROUND Olivopontocerebellar atrophy is an uncommon disorder with variable clinical manifestations that affects the cerebellum, the spinocerebellar tracts, and other structures of the brainstem. A deficiency of glutamate dehydrogenase, which results in an excess of glutamate, has been suggested to play a role in the pathogenesis of olivopontocerebellar atrophy. In experimental animals, toxic levels of glutamate are known to cause a selective loss of the b-wave on electroretinographic (ERG) testing and a degeneration of the inner retinal layers. One of the subtypes of olivopontocerebellar atrophy, type II, according to Hardings classification, is associated with retinal degeneration. METHODS The authors describe the ophthalmologic and ERG findings in a family with olivopontocerebellar atrophy type II. Histopathologic study of an eye from a 6-year-old family member who died of severe neurologic deterioration secondary to olivopontocerebellar atrophy type II was performed. RESULTS Electroretinographic changes may be present in affected family members who are entirely asymptomatic and have a normal ophthalmologic evaluation. The changes on the ERG in one patient suggest that cone dysfunction is one of the subtle changes that may be seen in olivopontocerebellar atrophy type II. Our ERG results did not show a selective loss of the b-wave but instead showed a loss of both the a-wave and b-wave in affected family members. Results of light and electron microscopic examination showed diffuse and extensive degeneration of the photoreceptors involving both rods and cones, the most prominent changes being present in the macula. An amorphous debris, presumably degenerated photoreceptors, was noted between the outer nuclear layer and retinal pigment epithelium. CONCLUSION Patients with olivopontocerebellar atrophy type II have photoreceptor abnormalities as revealed in abnormal ERGs seen in many patients and histopathologic study of an autopsy eye from an affected 6-year-old boy. Our results do not support the hypothesis that glutamate toxicity may be responsible for the development of retinal degeneration in this condition.

Lymphoma-associated retinopathy

OBJECTIVE To describe the clinical, electrophysiologic, and serologic findings in a patient with retinal degeneration associated with Hodgkins lymphoma. DESIGN Case report with ancillary immunohistochemical studies. METHODS A 24-year-old woman experienced night blindness and fundus abnormalities 1 week after initiation of chemotherapy for Hodgkins lymphoma. Visual fields and full-field electroretinograms (ERGs) were monitored over a 10-year period. Serum antibodies were studied on Western blot reactions on a solubilized extract of bovine retina. Serum antibodies were also evaluated through indirect immunohistochemistry on rhesus monkey retina. RESULTS Visual field and ERG amplitudes, initially abnormal, became reduced further over 10 years. Serum antibodies were identified that reacted to a retinal protein or proteins approximating 65 kd; these antibodies showed immunologic activity against photoreceptors. CONCLUSIONS A progressive paraneoplastic retinopathy can occur in association with Hodgkins lymphoma. The pathogenesis of the retinal degeneration appears to be related to a serum antibody that is reacting to a retinal protein or proteins of approximately 65 kd.

Acquired Heterochromia with Homer Syndrome in Two Adults

BACKGROUND Heterochromia iridis, asymmetry of iris pigmentation, has been well described with congenital Horner syndrome. Acquired heterochromia associated with lesions in the ocular sympathetic pathways in adulthood, however, is rare. METHODS Two cases are reported in which sympathectomy in adults resulted in ipsilateral Horner syndrome with heterochromia. In each case, pharmacologic testing with cocaine and hydroxyamphetamine was performed. RESULTS In both cases, sympathectomy occurred at the level of the second order neuron, but hydroxyamphetamine testing suggested at least partial third order neuron involvement. CONCLUSION Acquired heterochromia can occur in adults. The partial response to hydroxyamphetamine in the two cases presented may reflect trans-synaptic degeneration of the postganglionic neuron. A reduction in trophic influences on iris melanocytes may have contributed to the observed heterochromia.

Histopathologic Study of Variation in Severity of Retinitis Pigmentosa due to the Dominant Rhodopsin Mutation Pro23His

PURPOSE To compare histopathologic findings in an autopsy eye of an 87-year-old woman with retinitis pigmentosa and the rhodopsin mutation Pro23His with findings in an autopsy eye of a 77-year-old female relative (first cousin) with retinitis pigmentosa and the same mutation. DESIGN Histopathologic study. METHODS One eye from each patient was prepared for light and electron microscopy within 5 hours after death. Photoreceptor nuclear counts were performed. RESULTS Photoreceptor degeneration and intraretinal bone spicule pigmentation were evident in both cases. The younger patient had more extensive photoreceptor loss and more intraretinal pigmentation than her older relative. CONCLUSION A marked variation in the extent of retinal degeneration can be seen in two relatives with retinitis pigmentosa and rhodopsin, Pro23His. This study supports the idea that factors other than the primary gene defect are responsible for the severity of this condition.

Histopathologic and immunohistochemical study of dominant cone degeneration

PURPOSE To report the histopathologic and immunohistochemical findings in autosomal dominant cone degeneration. METHODS The autopsy eyes of a 75-year-old man with autosomal dominant cone degeneration were studied with both light and electron microscopy. In addition, immunofluorescent studies using antibodies to cone opsins and cone alpha transducin were performed. RESULTS Histopathologic examination of the fovea disclosed loss of photoreceptors and attenuated retinal pigment epithelium. Reduced numbers of cones could be seen in the parafovea, and only occasional cones were visible in the periphery; rods were preserved in the periphery. CONCLUSION The histopathologic and immunohistochemical findings in this case of dominantly inherited cone degeneration correlate well with the loss of cone function and preservation of normal or nearly normal rod function upon clinical examination. This condition affects red, green, and blue cones.

Retinal histopathology of an autopsy eye with advanced retinitis pigmentosa in a family with rhodopsin Glu181Lys.

PURPOSE To compare histologic findings in an autopsy eye of an 84-year-old man with advanced retinitis pigmentosa and rhodopsin, Glu181Lys, with two cases of autosomal dominant retinitis pigmentosa (one with rhodopsin, Pro23His, and one with rhodopsin, Cys110Arg) and with a normal control, all of comparable age. METHODS All eyes were prepared for light and electron microscopy within 6 hours after death. RESULTS Extensive photoreceptor degeneration was revealed in the eyes with retinitis pigmentosa. Some macular cones showed membranous swirls only in the eye with rhodopsin, Glu181Lys. CONCLUSION The retinal degeneration caused by rhodopsin, Glu181Lys, can feature membranous swirls in the inner segments of cones in the macula. These swirls have not been reported in other cases of dominant retinitis pigmentosa studied so far, and their pathogenesis remains to be defined.

Relative efficacy of the argon green, argon blue-green, and krypton red lasers for 10-0 nylon subconjunctival laser suture lysis.

BACKGROUND AND OBJECTIVE To determine the optimal wavelength for subconjunctival laser suture lysis. MATERIALS AND METHODS 130 black monofilament 10-0 nylon sutures were sewn subconjunctivally into the bare sclera of enucleated rabbit globes. The lowest energy levels facilitating laser suture lysis were determined for the argon green (514.5 NM), argon blue-green (488.0 NM, 514.5 NM), and krypton red (647.1 NM) wavelengths. In addition, absorption spectroscopy was performed on the suture material and conjunctiva using the Perkin Elmer W/VIS Lambda 2 spectrometer. RESULTS Krypton red produced the fewest buttonhole defects, and it was also the most efficient energy source for suture lysis (P = 0.0001) under nontenectomized conjunctiva. Absorbance spectra studies revealed peak absorbance at 628 NM for the 10-0 nylon suture material. CONCLUSIONS Based on animal and absorption spectroscopy studies, krypton red may be a safer and more efficient wavelength for subconjunctival laser suture lysis.

Atypical presumed CMV retinitis.

Cytomegalovirus (CMV) retinitis is a common and one of the most serious ophthalmic manifestations of the acquired immunodeficiency syndrome (AIDS). Early recognition is essential in the proper management of this necrotizing and progressive infection. We discuss an unusual presentation of CMV retinitis which appeared initially only in the foveal region.