Cataract Surgery in Retinitis Pigmentosa Patients

From the UCLA Retinitis Pigmentosa Registry, 30 patients with 54 aphakic eyes were studied in a retrospective analysis to evaluate the results of cataract surgery. Patients consisted of 19 men and 11 women, with an age range at the time of cataract surgery from 24 to 75 years (mean 47 years). After surgery all aphakic eyes showed some improvement in visual acuity; 83% of eyes demonstrated improvement in visual acuity of at least two lines on the Snellen chart, and 52% of eyes achieved a visual acuity of 20/50 or better. In all eyes, the postoperative visual field was unchanged when compared with the preoperative visual field. Subjectively, 83% of patients reported benefit from cataract surgery. Guidelines for the preoperative evaluation of retinitis pigmentosa (RP) patients with cataracts are presented.     

Post-menopausal bleeding: a rare presentation of metastatic uveal melanoma

Uveal melanoma differs from cutaneous melanoma in many ways, including its pattern of metastasis, and exhibits latency with clinical evidence of metastasis sometimes appearing many years after primary diagnosis. Most patients develop metastasis within the liver, but some may present with metastasis to other sites. We report a case of uveal melanoma that presented with post-menopausal bleeding due to metastasis. Further investigation revealed widespread metastatic disease and the patient was not fit for chemotherapy. She died two months after presentation: autopsy revealed metastases in many sites, including the uterus, right ovarian fibroma, kidney, mesentery, liver, lung, thyroid, bone marrow and skin. The immediate cause of death was cardiac tamponade due to a malignant effusion secondary to cardiac metastasis. This case illustrates the widespread metastatic potential of uveal melanoma and highlights the potential for unusual presentation of metastatic disease from this eye tumor.(Pathology Oncology Research Vol 12, No 3, 184–187)     

Fellow eye of patients with retinal detachment associated with macular hole and bilateral high myopia

PURPOSE: To estimate the risk of retinal detachment in the fellow eye of patients with bilateral high myopia who had retinal detachment associated with macular hole (MH-RD) in one eye. METHODS: The present study examined retrospectively 56 patients with bilateral high myopia who had MH-RD. To determine the incidence of involvement of the fellow eye, patients who completed a follow up of 12 months or longer were eligible for the current study. RESULTS: Of 56 patients with MH-RD due to high myopia, 54 had unilateral detachment at presentation and two had bilateral detachment. Of the 54 highly myopic fellow eyes without retinal detachment at presentation, 37 eyes underwent 12 or more months of documented follow up. Mean follow up after initial surgery to the primary eye was 6.5 +/- 4.9 years. During follow up, a macular hole without retinal detachment was noted in one (2.7%) of these 37 eyes. Three other eyes (8.1%) had MH-RD at 1, 2 and 7 years, respectively, after the initial surgery to the primary eye. At the final visit, 12 eyes (32%) had visual acuity of > or =6/9, whereas 12 eyes (32%) had visual acuity of < or =6/60. CONCLUSIONS: When patients with bilateral high myopia have MH-RD in one eye, they would be expected to be at increased risk of retinal detachment in the fellow eye.     

Transplantation of ocular tissue from a donor with sporadic Creutzfeldt-Jakob disease

BACKGROUND: One definite, one probable and several possible transmissions of sporadic Creutzfeldt-Jakob disease (sCJD) have followed corneal transplantation. We report an incident in the UK in 1997 in which both corneas and scleras from a donor, subsequently confirmed to have had sCJD, were transplanted. The final clinical outcome for two surviving recipients is still not yet known. CASE REPORT: In 1997, a 56-year-old woman died from biopsy-proven carcinoma of the bronchus. Both eyes were donated for transplantation. Shortly before she died, she had developed neurological symptoms thought to be due to brain metastases. However, the final result of a neurological post-mortem examination revealed evidence of sCJD. By this time the corneas had been transplanted, one 3 months previously into a 40-year-old man for keratoconus and the other 4 months previously into an 85-year-old woman for Fuchs' dystrophy. In addition, both scleras had been transplanted into a 36-year-old man undergoing oculoplastic reconstructive surgery. The surgeons and patients were informed and removal of tissue was advised but undertaken in only two of the patients. Immunohistochemistry failed to demonstrate the presence of the abnormal form of the prion protein in explanted tissue. CONCLUSIONS: Eight years after the event, two patients remain free of symptoms suggestive of iatrogenic CJD (http://www.cjd.ed.ac.uk/criteria.htm). The third having died aged 92 years, some 7 years after surgery, showing signs of dementia not considered indicative of iatrogenic CJD. Nevertheless this adverse incident attracted substantial publicity. Coupled with continuing concerns in the UK about person-to-person transmission of variant CJD, this has lead to a number of important consequences in donor eye retrieval, ocular tissue banking and transplantation.     

Tricyclic response in obsessive compulsive disorder

Therapeutic responses to the tricyclic antidepressant clomipramine have been demonstrated in five double blind studies of patients with obsessive compulsive disorder. Biological alterations in patients with obsessive compulsive disorder resemble those of depressed patients for the dexamethasone suppression test, for some measures of sleep physiology, and in similar neuroendocrine responses to clonidine. Clomipramine's antiobsessional effect does not require high baseline depression ratings or biological abnormalities similar to those seen in depressives. Preliminary results suggest that in contrast to depressives, patients with obsessive compulsive disorder may respond to clomipramine but not to the tricyclic antidepressant desipramine.     

Elastic and precursor fibres in the normal human eye

Completely formed elastic fibres consist of a core of amorphous elastin within a mantle of microfibrils. The fibrillar component may occur as isolated bundles (oxytalan) or may be randomly intermingled with variable amounts of elastin (elaunin). The distribution of both mature elastic and incomplete oxytalan and elaunin fibres in the different parts of 53 human eyes from foetal life to old age is described, as evaluated by light microscopy of histochemical preparations. In general elastic tissue was most evident in the collagenous structures save the adult cornea in which incomplete elastic fibres occur rarely and then late in life. Precursor forms predominate in early childhood and show a limited and slow capacity for maturation. The suspensory zonular fibres of the lens appear to be composed largely of oxytalan throughout life. There is also evidence that corneal epithelium and endothelium, irideal smooth muscle and, less certainly, retinal pigment epithelium can synthesise the fibrillar component, although not elastin, of elastic tissue.     

Ocular limit cycles induced by delayed retinal feedback

Lisberger's and Robinson's models of smooth pursuit predict very different results from altering retinal feedback delay. We have therefore investigated the effects of increasing the retinal feedback time delay in three normal human subjects by means of an artificial feedback paradigm. When additional delays were incorporated into the retinal feedback path a threshold was reached beyond which the eye exhibited sustained self-excited oscillations or limit cycles. The oscillation period increased linearly (as the added delay was increased) with slopes ranging from 1.41 to 1.6 with zero-delay intercepts of between 212 and 306 ms. Contrary to our experimental findings the Robinson and Lisberger models predict that the plot of oscillation period against added delay should have a slope of 3.4 and 2.7 and an intercept of 479 and 554 ms, respectively. Neither model produced comparable limit cycles, both being unstable at delays greater than 280 ms. Our results imply that the models of smooth pursuit need to incorporate predictive control.     

A method of averaging evoked potentials that precede saccadic (rapid) eye movements

A technique is described which allows one to use potentials generated by saccadic (rapid) eye movement to trigger a computer of average transients before, during or after the saccade occurs. The system provides an independent adjustment of a time base that is synchronized with the potentials generated by the rapid eye movements. The analog signal conditioning methods and methods of achieving a reliable preset time delay are discussed. Data obtained from animals are portrayed.