Characteristics of patients presenting with central retinal artery occlusion with and without giant cell arteritis.

BACKGROUND: In patients with concurrent central retinal artery occlusion (CRAO) and giant cell arteritis (GCA), prompt recognition and early treatment are crucial to prevent further visual loss in the contralateral eye. The objective of this study was to describe a series of patients with CRAO resulting from GCA and to compare them with patients with isolated CRAO. METHODS: The patient database for a retina service in Philadelphia was searched to identify patients admitted between 1983 and 1993 with a diagnosis of biopsyproven GCA and CRAO. For every patient with CRAO caused by GCA, the next patient admitted for management of acute isolated CRAO was identified; these latter patients constituted the control group. The visual acuity and baseline characteristics of the two groups were compared. RESULTS: Eleven patients with acute CRAO and GCA were admitted during the study period. In both the case and control groups seven patients (64%) were women and nine patients (82%) were white. Six subjects (54%) in the case group and seven (64%) in the control group had a history of hypertension; the values for diabetes mellitus were two (18%) and zero respectively. Four patients (36%) with CRAO and GCA were cigarette smokers, compared with eight patients (73%) with CRAO alone. None of these differences were statistically significant. Patients with CRAO related to GCA were more likely than those with isolated CRAO to have counting fingers or better vision at presentation (odds ratio 2.22 [95% confidence interval 0.37 to 13.2]), but this trend was not statistically significant. INTERPRETATION: Patients who presented with CRAO related to GCA were more than twice as likely as those with CRAO alone to have counting fingers or better visual acuity at the time of presentation. However, owing to the small sample, the power of this study to detect a true difference between the two groups was limited.

Clinical management of posterior chamber intraocular lens implants dislocated in the vitreous cavity.

BACKGROUND AND OBJECTIVE: To discuss the options for management and review the authors' experience with dislocated posterior chamber intraocular lens implants. PATIENTS AND METHODS: A retrospective review was performed over a 3-year period of 12 consecutive patients with posterior chamber intraocular lens (PC IOL) implants dislocated into the vitreous cavity. The patients were managed with pars plana vitrectomy, repositioning or exchange, and transscleral suture fixation of the PC IOL. RESULTS: The visual acuity was 20/50 or better in 9 patients and the transscleral suture fixated PC IOL was in good position in 12 patients at the most recent follow-up. Perioperative complications included corneal edema, cystoid macular edema, retinal breaks and detachments, and suture erosion. CONCLUSION: Visual and anatomic outcomes were favorable.

Retinal tolerance of an implantable light source for use during vitrectomy surgery.

To assess for the possible development of a phototoxic lesion, we exposed five Dutch belted rabbit retinas to constant illumination with an implantable "chandelier" light source at maximal intensity for 1 hour. No clinically apparent lesion developed in any of the experimentally treated eyes by 48 to 72 hours posttreatment. Light and electron microscopic examination failed to reveal any of the characteristic changes of retinal phototoxicity. A control eye treated with a 20-minute exposure to a standard endoiluminator probe at maximal intensity held 2 mm from the retinal surface demonstrated typical light and electron microscopic phototoxic abnormalities, whereas a retina similarly treated with a 5-minute exposure was normal. We have confirmed that a standard endoilluminator probe can create a phototoxic lesion in the experimental setting. Furthermore, no phototoxicity from the sustained retinal exposure to a fixed, implantable light source for a clinically relevant duration could be demonstrated.

Retinal toxicity of intravitreal gentamicin.

The short- and long-term effects of a 10-mg dose of intravitreal gentamicin were studied in the subhuman primate eye with regard to the changes in clinical appearance, fluorescein angiography, electroretinography, histopathologic finding, and electron microscopy. The gentamicin produced retinal whitening with a cherry-red spot, generalized vascular incompetence, diffuse retinal necrosis, thrombosis of the large retinal blood vessels, widespread loss of the retinal capillary pericytes and endothelial cells, and a rapid extinction of the electroretinogram.

Retinitis pigmentosa.

Retinitis pigmentosa is a subset of inherited diseases associated with progressive degeneration of the retina otherwise classified as retinal dystrophies. Clinically, patients have nyctalopia (night blindness), progressive visual field loss, and eventually loss of central vision. Patients with retinitis pigmentosa should be evaluated for other ocular conditions that may simulate the condition, as well as for systemic disorders.

Abnormal ocular pneumoplethysmographic results in unilateral neovascular glaucoma.

Little is known about the predictive value of ocular pneumoplethysmography in patients with ophthalmic disease. We evaluated eight patients with unilateral increased intraocular pressure due to neovascular glaucoma who did not have evidence of severe extracranial carotid stenosis by duplex scanning and continuous-wave Doppler ultrasound. The ophthalmic systolic pressure measured by ocular pneumoplethysmography was decreased in the affected eye of all eight patients, indicating that neovascular glaucoma may be a cause of abnormal ocular pneumoplethysmographic results. Patients with neovascular glaucoma tended to have larger interocular ophthalmic systolic pressure differences than other patients with false-positive ocular pneumoplethysmographic results by noninvasive criteria.

Flurbiprofen sodium to prevent intraoperative miosis during vitreoretinal surgery.

To assess the efficacy of flurbiprofen sodium 0.03% at maintaining pupillary dilation during vitreoretinal surgery, we performed a randomized, double-masked, controlled trial of 139 consecutive patients. The mean decrease in pupil size during surgery in patients who received flurbiprofen was 0.9 mm; for patients who did not receive the drug it was 0.8 mm. The type of surgery performed (vitrectomy or scleral buckle), gender, age, lens status, and a history of diabetes or previous intraocular surgery were assessed and the addition of flurbiprofen to routine preoperative dilation did not significantly affect the mean change in pupil size for any of these subgroups. Of the nine patients who developed at least 3 mm of miosis, five received flurbiprofen and four did not. Use of flurbiprofen did not appear to reduce intraoperative miosis during vitreoretinal surgery in a clinically meaningful manner.

Metastasis of choroidal melanoma to the contralateral choroid, orbit, and eyelid.

A 52-year-old woman was found to have a small juxtapapillary pigmented lesion in the choroid of the left eye. This lesion remained clinically stationary for one year, but subsequent growth prompted enucleation of the eye. The tumour was diagnosed histologically as a choroidal malignant melanoma of mixed cell type. Approximately 52 months later the patient developed proptosis of the contralateral (right) eye. Orbital ultrasonography showed a large mass in the right orbit, which was confirmed by needle biopsy to be a melanoma. In addition the patient was found to have metastatic melanoma to the choroid, right lower eyelid area, and liver. The development of simultaneous orbital, choroidal, and eyelid metastases from a contralateral choroidal melanoma is of ophthalmic interest and appears to be unique.

Multiple myeloma involving the iris.

Intraocular invasion by neoplastic plasma cells is a rare ophthalmic manifestation of plasma cell dyscrasias. A 67-year-old man who had documented multiple myeloma presented with an infiltration of the iris that simulated a nongranulomatous uveitis. Cytologic examination of the aspirate obtained by anterior chamber paracentesis demonstrated that the infiltrate was composed of neoplastic plasma cells.

Clinicopathologic correlation of a prepapillary vascular loop.

The clinical, fluorescein angiographic, and histopathologic features of a prepapillary vascular loop are described in a patient whose eye was obtained postmortem. The prepapillary vascular loop communicated with the retinal arterial system and did not have an internal elastic lamina. It was supported by a connective tissue sheath that was lined by a cellular lamina. The cellular lamina was continuous with the inner retina, isolating the vascular loop from the vitreous. The histologic findings were correlated with the clinical examination and fluorescein angiography.

Traumatic extrusion of posterior chamber lenses: clinical and experimental correlations.

Five cases of traumatic expulsion of posterior chamber intraocular lens implants are presented. The syndrome is characterized by expulsion of the lens, iris damage, and intraocular hemorrhage. In experiments with donor human eyes we were able to reproduce the syndrome with 0.68 joules of energy, which is well below that encountered in common environmental situations.

Krypton red laser photocoagulation for subretinal neovascularization.

One hundred fifty-seven patients with subretinal neovascularization (SRN) were treated in a prospective, nonrandomized, consecutive study with the krypton red laser (KRL). The patients were analyzed with respect to age, etiology of the SRN, location of the SRN, and pre- and post-treatment visual acuity in patients with at least three months follow-up. Previous studies have not investigated KRL photocoagulation within the foveal avascular zone (FAZ). The results of this study compare favorably with other large series in which patients with SRN located outside the FAZ were treated with the argon blue-green laser (ABGL).

The effect of pH on the transfer of fluorescein across the blood-retinal barrier.

The blood-retinal barrier (BRB) might be governed by the same permeability principles as the blood-brain barrier (BBB). For a weak acid like fluorescein, BRB permeability would be proportional to its pH-dependent lipid solubility, according to the pH partition hypothesis. A range of metabolic acidosis was produced in 20 rats by the oral administration of NH4Cl; six additional rats received normal saline. Four hours later, vitreous fluorophotometry, venous fluorescein values, and arterial pH were measured. Significant linear relationships were found between vitreous fluorophotometry readings and blood hydrogen ion concentrations (p less than 0.025) and plasma fluorescein concentrations (p less than 0.05). According to the linear relationship, changing the pH from 7.4 to 7.3 or 6.9 would result in an increase in vitreous fluorophotometry reading of 8.5 or 72%, respectively. Since the pH partition hypothesis predicts values of 52 or 640% our results suggest that the BRB conforms less to the hypothesis than does the BBB. Furthermore, although pH changes of a magnitude able to influence vitreous fluorophotometry readings substantially may occur under experimental conditions in animals, they are unlikely to occur in ambulatory human patients.

Intraocular metastases from cutaneous malignant melanoma.

We present a consecutive series of ten patients (12 eyes) with symptomatic intraocular metastases from primary cutaneous malignant melanoma, with emphasis on the variation in clinical features and extent of intraocular involvement. An investigation of each patient's history and the presence of other concurrent metastatic foci help to establish the diagnosis. Palliative radiation therapy may help to control the intraocular metastatic foci and limit the visual loss.