Familial primary pulmonary hypertension and associated ocular findings.

BACKGROUND: Familial primary pulmonary hypertension (PPH) is a rare, fatal, autosomal dominant disease that results in right heart failure from idiopathic obliteration of the pulmonary arteries. Patients develop stagnation of venous blood flow and elevated venous pressure. METHODS: The authors retrospectively reviewed the clinical records of three patients diagnosed with PPH that was confirmed on the basis of physical examination, chest X-ray, electrocardiogram, and echocardiogram. Cardiac catheterization excluded cardiac shunt and other secondary causes of pulmonary hypertension. RESULTS: Two patients presented with a clinical picture resembling venous stasis retinopathy, and one with bilateral choroidal detachments. Two patients had delayed choroidal filling on fluorescein angiography, which was confirmed in one patient with indocyanine green videoangiography. CONCLUSIONS: Elevated venous pressure found in PPH is responsible for the delayed choroidal perfusion and the reduced venous blood outflow. This explains the clinical findings of venous stasis retinopathy and choroidal detachments seen in these patients.

Ocular myasthenia and nitrofurantoin.

PURPOSE: To report a case of ocular myasthenia associated with administration of nitrofurantoin. METHODS: Case report and review of the literature. RESULTS: While taking nitrofurantoin after urinary tract surgery, a 10-year-old female developed diplopia and ptosis. Sleep test confirmed ocular myasthenia. Signs and symptoms resolved after discontinuation of the drug. CONCLUSION: Ocular myasthenia may be associated with nitrofurantoin administration.

Retinal vascular nonperfusion and retinal neovascularization as a consequence of cytomegalovirus retinitis and cryptococcal choroiditis.

BACKGROUND: Cytomegalovirus retinitis and cryptococcal choroiditis are opportunistic infections in patients with acquired immune deficiency syndrome. These infections are associated with a retinal vasculitis and vascular attenuation. METHODS: We present a case of retinal vascular nonperfusion and retinal neovascularization in a patient with acquired immune deficiency syndrome. RESULTS: Retinal vascular nonperfusion and retinal neovascularization were confirmed by fluorescein angiography. CONCLUSIONS: This is the first reported case of retinal neovascularization in a patient with acquired immune deficiency syndrome, ocular cytomegalovirus retinitis, and cryptococcal infection.

Macular epiretinal membrane formation and treated retinal breaks.

PURPOSE: We sought to determine the incidence of macular epiretinal membrane formation in eyes treated for retinal breaks after three different modalities of treatment: laser photocoagulation, cryotherapy, or both. METHODS: We reviewed the charts of 262 consecutive patients with a diagnosis of retinal tears and included 205 patients who had more than six months of follow-up. RESULTS: One hundred ninety-five patients were treated. One hundred seventy of these patients had retinal breaks in one eye and 25 patients had breaks in both eyes, for a total of 220 treated eyes. Cryopexy was applied in 125 eyes, laser retinopexy in 73 eyes, and both modalities in 22 eyes. Macular epiretinal membranes developed in a total of 26 eyes: 12 in the cryopexy group, ten in the laser-treated group, and four in the dual modality group. No statistically significant difference, at a level of P < or = .01, was seen in the rate of epiretinal membrane formation between the different treatment modalities. No statistically significant difference, at a level of P < or = .01, was seen in the rate of epiretinal membrane formation in the presence or absence of vitreous hemorrhage or in the type of precedent retinal break. CONCLUSIONS: After treatment of retinal breaks with laser photocoagulation and cryotherapy, no statistically significant difference in the incidence of macular epiretinal membrane formation was demonstrated.

Macular pseudohypopyon from secondary syphilis.

PURPOSE/METHODS: Acute syphilitic posterior placoid chorioretinitis causes visual loss in patients with secondary syphilis. The condition is characterized by vitreitis and large, yellow placoid lesions in the macula. We examined a patient with syphilis who had a serious retinal detachment and an exudative fluid meniscus (pseudohypopyon). RESULTS/CONCLUSIONS: Visual recovery and complete resolution of the chorioretinal lesion occurred after intravenous penicillin therapy. Secondary syphilis should be considered in the differential diagnosis of any patient with a macular pseudohypopyon.

Hypopyon uveitis in patients with acquired immunodeficiency syndrome treated for systemic Mycobacterium avium complex infection with rifabutin.

OBJECTIVE: Iridocyclitis has been identified as a dosage-dependent side effect in patients with the acquired immunodeficiency syndrome (AIDS) who are treated for Mycobacterium avium complex (MAC) infection with systemic rifabutin. We reviewed cases of acute hypopyon uveitis occurring in patients with AIDS to establish whether there was an association. DESIGN: Retrospective case series. SETTING: Outpatient clinic and inpatient hospital-based ophthalmology referral practice and infectious disease specialty service. PATIENTS: Seven patients with AIDS, aged 10 to 40 years, presenting with acute unilateral hypopyon mimicking infectious endophthalmitis. MAIN OUTCOME MEASURES: Findings from complete ophthalmological evaluation and ancillary laboratory testing. RESULTS: At the time of presentation, all seven patients were receiving treatment for MAC infection with rifabutin (dosage range, 300 to 600 mg/d) and clarithromycin. Results of microbiological investigations in five patients were negative. Iridocyclitis became bilateral in all seven patients, and hypopyon developed in the contralateral eye in five of seven patients. Hypopyon resolved rapidly with intensive topical corticosteroid therapy. Residual inflammation responded to topical corticosteroids with or without reduction of the rifabutin dosage. CONCLUSIONS: Concomitant use of rifabutin, clarithromycin, and fluconazole may precipitate hypopyon uveitis in patients with AIDS being treated for MAC infection.

Perilimbal anesthesia for pars plana vitrectomy.

We attempted to determine the efficacy of perilimbal anesthesia with Monitored Anesthesia Care (intravenous sedation with monitoring of the patients' vital signs by anesthesia) in patients undergoing pars plana vitrectomy. We selected 15 patients who were screened for any physical condition that would preclude them from lying supine and motionless for the duration of the surgery. Patients with complicated vitreoretinal abnormalities and patients who required reoperations were excluded. The patients ranged in age from 55 to 79 years and included three with nonclearing vitreous hemorrhage, seven with macular hole, three with macular pucker, one with proliferative diabetic retinopathy, and one with endophthalmitis. Total operating time ranged from 45 to 135 minutes (mean, 102.3 +/- 22.0 minutes). No complaints of discomfort were reported. All operations were completed without additional anesthetic. Our findings demonstrate that pars plana vitrectomy using perilimbal anesthesia with monitored anesthesia care is effective in selected patients. This form of anesthesia administration eliminates the risks of inadvertent globe perforation associated with retrobulbar and perilimbal anesthesia and the risks of general anesthesia.

Drainage of subretinal fluid in retinal detachment surgery with the El-Mofty insulated diathermy electrode.

PURPOSE: A technique that uses the El-Mofty/Schepens diathermy tip (MIRA, Inc.) to effect drainage of subretinal fluid during scleral buckling surgery is described. The efficacy of this drainage technique and its complication rate in a series of consecutive patients is discussed. METHODS: The study included all of the scleral buckling procedures performed at the Retina Service for retinal detachments in which this technique was used. The El-Mofty/Schepens diathermy tip was first used to cauterize the choroid at the drainage site at low power, thus rendering it avascular, and then at higher power, to cause vaporization of the choroid, and allow spontaneous drainage of subretinal fluid. The success rate and all intraoperative and postoperative complications were recorded. RESULTS: This technique achieved successful spontaneous drainage in 53 (82.8%) of 64 consecutive cases. Complications that are occasionally associated with the drainage of subretinal fluid, including iatrogenic retinal holes, choroidal hemorrhage, and retinal incarceration in the sclerotomy site, were not seen in any of the cases. CONCLUSION: This method provides a simple and safe technique for the drainage of subretinal fluid that obviates the need to directly perforate the choroid.

Retinal toxicity of high dose intravitreal ganciclovir.

BACKGROUND: Intravitreal administration of ganciclovir has been used to treat cytomegalovirus (CMV) retinitis in patients with acquired immune deficiency syndrome (AIDS) who are unable to tolerate systemic antiviral therapy. Although retinal toxicity from intravitreal ganciclovir has been observed in animal experiments, to our knowledge, retinal toxicity from intravitreal ganciclovir has not been reported in humans. METHODS: A case of inadvertent intravitreous injection of a high dose of ganciclovir (40 mg/0.1 ml) for CMV retinitis in a patient with AIDS is presented. RESULTS: Despite immediate intervention with vitreous surgery, permanent retinal damage and visual loss developed. Clinical observations and photographic documentation are provided. CONCLUSION: Retinal toxicity can occur from a high-dose intravitreal ganciclovir injection. This toxicity may result from the high alkaline nature of this preparation, from osmotic damage, or from a direct effect of the concentrated ganciclovir.

Kinetics of myoglobin release and prediction of myocardial myoglobin depletion after coronary artery reperfusion.

To better define the usefulness of blood myoglobin measurements in evaluating the effectiveness of attempted thrombolysis, we studied the kinetics of myoglobin entry into and removal from the circulation after coronary artery reperfusion and the relation between directly measured depletion of myocardial myoglobin after coronary occlusion and reperfusion and the amount of depletion predicted from plasma myoglobin concentration-time curves. Initially, canine myoglobin was administered to 11 dogs by both bolus injection and 40-minute infusion, and the subsequent disappearance patterns of myoglobin from plasma monitored by radioimmunoassay. A monoexponential regression line (corresponding to a one-compartment model) and a biexponential regression line (corresponding to a two-compartment model) were determined for each set of washout data, the kinetic parameters were calculated, and the goodness of fit of each model was assessed. Results were similar after both methods of myoglobin administration. In five of 11 animals, the one-compartment model described the myoglobin kinetics better; in the other six animals, the two-compartment model was statistically superior, but values for the volume of distribution and elimination rate constant differed by only 10% from the one-compartment estimates. After bolus administration of myoglobin and with a one-compartment model, the volume of distribution of myoglobin was determined to be 1,601 +/- 77 (SEM) ml, representing 6.8 +/- 0.2% of total body weight; the elimination rate constant averaged 0.132 +/- 0.006/min and corresponded to a mean half-time of disappearance of 5.5 +/- 0.2 minutes.(ABSTRACT TRUNCATED AT 250 WORDS)

Rapid effects of insulin on the cycling of the insulin receptor in a human monocyte cell line (U-937).

The insulin receptor and its regulation by insulin was studied in U-937 monocytes, a human cell line with properties similar to those of normal peripheral blood monocytes. Treatment of this cell with insulin for 8-16 h produced an overall loss in the insulin receptor, i.e., a loss of receptors from the cell surface and internal pools. In contrast, short-term insulin treatment (15-30 min) caused a reduction in cell surface receptors but an increase in the internal receptors, as judged by pronase treatment at 4 degrees C to distinguish receptor location. After the removal of insulin and pronase, the internalized receptors were rapidly reinserted back into the cell surface after warming to 37 degrees C. Further studies showed an insulin-mediated increase in fluid-phase pinocytosis as measured by horseradish peroxidase (HRP) uptake. The amount of HRP accumulation and the time course for this stimulation were similar to those for receptor internalization. These features plus other results suggest that the insulin-stimulated internalization of insulin receptors may require an acceleration in the rate of pinocytic vesicle formation.

Sequence analysis of ultraviolet-induced mutations in M13lacZ hybrid phage DNA.

We have studied the specificity of ultraviolet (u.v.) mutagenesis in single-stranded DNA phage by analyzing u.v.-induced forward mutations in the lac insert of M13mp2 hybrid phage. Sequence analysis of 114 lac mutants derived from u.v.-irradiated phage grown in u.v.-irradiated cells showed that ultraviolet induces mainly single-nucleotide substitutions and deletions in progeny phage DNA. A total of 74% of the single-base substitution mutations occurred at sites of adjacent pyrimidines in the single-stranded DNA, with both T----C and C----T transitions predominating in the u.v. spectrum. Single-nucleotide deletion mutations occurred preferentially in tracts of repeated pyrimidine nucleotides. Tandem, double-base substitutions did not represent a major class of u.v.-induced mutations, but nearly 10% of mutant clones contained multiple, non-tandem nucleotide changes.