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Biomedical subjects

R J Olk

Publications and source records attributed to R J Olk.

At least 73 records · Page 4Linked to original sources
PubMed1986

Modified grid argon (blue-green) laser photocoagulation for diffuse diabetic macular edema.

One hundred sixty eyes of 92 patients with diffuse diabetic maculopathy with or without cystoid macular edema were enrolled in a prospective randomized clinical trial to determine the efficacy of "modified grid" argon (blue-green) laser photocoagulation. At the 12- and 24-month follow-ups, visual acuity significantly improved in treated eyes (P = 0.00007 and P = 0.00031, respectively) compared to the observation group. In addition, at the 12- and 24-month follow-ups, visual acuity significantly worsened in observation eyes (P = 0.00007 and P = 0.0007, respectively) compared to the treatment group. The following factors did not statistically alter the visual prognosis: a history of systemic hypertension (P = 0.2921); systemic vascular disease (P = 0.5324); cystoid macular edema (P = 0.1010); and initial poor visual acuity (P = 0.3032).

Adult↗
PubMed1986

Natural history of retinal pigment epithelial detachments in age-related macular degeneration.

The natural history of 100 eyes of 93 patients with retinal pigment epithelial detachment (PED) and bilateral age-related macular degeneration (AMD) was retrospectively studied for a minimum of 12 months in the offices of Retina Consultants, Ltd. Detachment was defined as serous in 46 eyes, turbid in 12 eyes, hemorrhagic without evident neovascular membrane (NVM) in 20 eyes, and hemorrhagic with angiographically proven NVM in 17 eyes. Final visual results demonstrated visual acuity of 20/200 or worse in 33% of serous PED, 83% of turbid PED, and 89% of hemorrhagic PED. Despite strict inclusion criteria, 26% of serous PED developed NVM by one year and 49% of serous PED developed NVM by three years. Variables associated with NVM development in serous PED include older patient age, larger detachment size, presence of subretinal fluid at initial examination, and disciform scar in the fellow eye at presentation.

Age Factors↗
PubMed1986

Comparison of intraocular irrigating solutions in pars plana vitrectomy.

A prospective, randomized, masked clinical study was conducted to examine the effects of pars plana vitrectomy on the corneal endothelium comparing Balanced Salt Solution (BSS) to BSS-Plus as an intraocular irrigating solution. Seventy-one patients were followed for at least six months. A significant 6.9% decrease in endothelial cell density was observed among all patients at six months postoperatively, compared to preoperative values, using the contralateral eye as a control. However, no significant difference in endothelial cell loss was found between BSS and BSS-Plus eyes. Both aphakic eyes and those undergoing lensectomy (with vitrectomy) showed a significantly greater reduction of endothelial cell density at six months compared to phakic eyes. No significant difference in corneal thickness was observed at six months postoperatively compared to preoperative values. For the one-year duration of our study BSS was as efficacious in preserving the integrity of the corneal endothelium as was BSS-Plus.

Acetates↗
PubMed1986

Limited retinal detachment. A retrospective analysis of treatment with transconjunctival retinocryopexy.

Two hundred forty-one eyes with a "limited retinal detachment" were treated between 1967 and 1983 by transconjunctival retinocryopexy without scleral buckling. Follow-up ranged from 6 months to 10 years (mean, of 34 months). Anatomic reattachment was accomplished with retinocryopexy alone in 95% (228 eyes) of cases. Thirteen eyes (5%) were anatomic failures, but 12 of these were subsequently reattached with additional surgery. Risk factors for anatomic failure included multiple breaks, vitreous hemorrhage, and breaks with a rolled posterior edge. Visual results indicated that 229 eyes (95%) had stable or improved vision, while 12 eyes (5%) lost two or more Snellen lines. Causes for visual deterioration included premacular fibroplasia, proliferative vitreoretinopathy, and preexisting ocular pathology. Single breaks occurred in 172 eyes (71.4%), and multiple breaks in 69 eyes (28.6%). Associated clinical findings included high myopia (17%), surgical aphakia (12%), and retinal detachment in the fellow eye (27%).

Conjunctiva↗
PubMed1985

Vitrectomy without scleral buckling for primary rhegmatogenous retinal detachment.

Trans pars plana vitrectomy with air-fluid exchange was performed on 29 selected cases of primary rhegmatogenous retinal detachment in which scleral buckling would be the usual surgical approach. The group contained 20 phakic eyes, two aphakic eyes, and seven pseudophakic eyes; the macula was detached preoperatively in 17 eyes (66%). The reattachment rate after one operation was 79% (23 of 29 eyes); after two operations this increased to 93% (27 of 29 eyes). Visual acuities of 20/50 or better were achieved in 22 of 27 successfully treated cases (81%). Vitrectomy without scleral buckling may allow retinal reattachment with excellent visual results in selected cases of primary rhegmatogenous retinal detachment.

Adolescent↗
PubMed1985

Treatment of recurrent juxtafoveal subretinal neovascular membranes with krypton red laser photocoagulation.

Thirty-seven eyes initially treated with argon blue-green, argon green, or krypton red laser photocoagulation demonstrated a recurrent subretinal neovascular membrane (SRNVM) at the edge of the treatment scar extending into the foveal avascular zone and were retreated with krypton red laser photocoagulation. The subretinal neovascular membrane was due to the presumed ocular histoplasmosis syndrome (POHS) in 10 eyes, aging macular choroidal degeneration (AMCD) in 22 eyes, and miscellaneous causes in five eyes. Anatomic success, defined as complete obliteration of the recurrent SRNVM, was achieved in 26 eyes (70%). When compared to pretreatment visual acuities, 23 of 37 eyes (62.2%) had stable or improved postoperative visual acuities during the follow-up period. Twenty-six eyes were retreated one time; nine eyes required two retreatments; and two eyes required three retreatments. Final visual results showed visual acuity greater than or equal to 20/40 in 7 eyes (18.9%); visual acuity greater than or equal to 20/80 in 16 eyes (43.8%); visual acuity greater than or equal to 20/100 in 19 eyes (51.4%); visual acuity greater than or equal to 20/200 in 27 eyes (73%); and visual acuity greater than or equal to 20/400 in 34 eyes (91.9%).

Adult↗
PubMed1984

Preoperative antibiotic soaking of silicone sponges. Does it make a difference?

A prospective randomized trial was carried out during the years 1974 to 1981 to determine whether preoperative antibiotic soaking of silicone sponges used in retinal detachment surgery would reduce the incidence of postoperative infection and extrusion. During this period 2972 consecutive primary scleral buckles were performed and in 921 (31%) of the cases an episcleral sponge was utilized either alone or in conjunction with a hard silicone encircling band. In alternate cases the sponge was soaked in an antibiotic solution for at least 30 minutes prior to insertion. In the remaining cases the sponge was not soaked. Overall, a statistically significant (P = 0.00018) seven-fold reduction in the rate of infection or extrusion was observed in cases where the silicone sponge was soaked preoperatively in antibiotics. An additional result of the study showed the rate of sponge removal was significantly increased by the use of multiple episcleral sponges (P = 0.00002).

Anti-Bacterial Agents↗
PubMed1984

Subfoveal and juxtafoveal subretinal neovascularization in the presumed ocular histoplasmosis syndrome. Visual prognosis.

The visual prognosis of 148 eyes in patients with an active subfoveal or juxtafoveal subretinal neovascular membrane (SRNVM) in the presumed ocular histoplasmosis syndrome (POHS) was reviewed. Average follow-up was 39 months. One hundred twenty of 148 eyes (81.1%) had a final visual acuity worse than 20/40. One hundred three of 148 eyes (69.6%) had a final visual acuity equal to or worse than 20/200. Systemic and/or periocular steroids had no effect on final visual outcome. Factors affecting final visual outcome are described and prognosis in the fellow eye is discussed.

Adolescent↗
PubMed1983

Solitary choroidal mass as the presenting sign in systemic sarcoidosis.

A solitary choroidal mass with an overlying neurosensory retinal detachment was seen in an otherwise healthy 25-year-old Caucasian female. Ocular and general physical examinations, serum chemistry, and pathological examination of a lymph node biopsy confirmed sarcoidosis as the cause for the choroidal mass. Treatment with systemic steroids resulted in resolution of the lesion and return of normal visual acuity.

Adult↗
PubMed1983

Irreversible visual loss in Waldenström's macroglobulinaemia.

A patient with Waldenström's macroglobulinaemia presented with visual reduction in both eyes. The funduscopic and angiographic demonstrations of venous engorgement ('string of sausages'), retinal haemorrhages at all levels, retinal and disc oedema, and serous detachment of the maculas were consistent with this diagnosis. The cryoprecipitation of the immunoglobulin at a temperature slightly below body temperature precluded routine blood studies and plasmapheresis. Plasmapheresis was ultimately performed without difficulty with the patient and equipment at 88 degrees F (31 degrees C). Despite marked improvement in the funduscopic and angiographic appearance of the retina, perifoveal capillary nonperfusion and serous elevation of the macula persisted. Even when the maculas flattened in both eyes, no visual recovery occurred. Early diagnosis, even on a clinical basis when laboratory studies cannot be performed, and early plasmapheresis to reduce serum viscosity are warranted to prevent intravascular occlusion in the perifoveal capillary bed, deposition of immunoglobulin in the retina, and transudation in the subretinal space.

Blood Viscosity↗
PubMed1982

Natural course of choroidal neovascular membranes within the foveal avascular zone in senile macular degeneration.

We divided 96 eyes (93 patients) with senile macular degeneration and choroidal neovascular membranes into two groups--those with juxtafoveal membranes (1 to 250 mu from the center of the foveal avascular zone) and those with subfoveal membranes (0 mu from the center of the zone). After an average follow-up period of 21 months, one of 38 eyes in the juxtafoveal group (3%) had improved two or more lines on the Snellen chart, three eyes (8%) had remained the same, and 34 eyes (89%) had lost two or more lines on the Snellen chart. Although 35 of the 38 eyes (92%) had had initial visual acuities of 6/30 (20/100) or better, 27 eyes (71%) had become legally blind. Of the 58 eyes in the subfoveal group, 18 (31%) had remained the same or improved and 40 (69%) had lost two or more lines on the Snellen chart; 41 (70%) had final visual acuities of 6/60 (20/20) or worse. Of the 26 eyes in the subfoveal group that had had initial visual acuities of 6/60 (20/100) or better (45%). four (15%) had stayed the same and 22 (85%) had lost two or more lines on the Snellen chart. Fourteen of the 26 eyes (54%) had final visual acuities of 6/60 (20/200) or worse. Exudative maculopathy developed in the second eye in 13% of patients who initially had unilateral choroidal neovascularization after 12 months, in 22% after 24 months, and in 29% after 36 months, using life table analysis.

Adult↗
PubMed1981

Long-term follow-up of ocular histoplasmosis treated by argon laser photocoagulation.

Sixty-eight eyes in 67 patients with a histoplasmic neovascular membrane treated with Argon laser photocoagulation between 1972 and 1978 are reviewed. Factors affecting visual outcome and causes of visual failure are discussed. Twenty of 68 eyes (nearly 30%) experienced a recurrent or new SRNVM after initially successful treatment. Final evaluation of Argon laser photocoagulation for histoplasmic neovascular membrane must await the outcome of the Macular Photocoagulation Study.

Adult↗
PubMedDate not supplied

Branch retinal artery occlusion (BRAO) combined with branch retinal vein occlusion (BRVO) and optic disc neovascularization associated with HIV and CMV retinitis.

Two vaso-occlusive events, branch retinal artery occlusion (BRAO) and branch retinal vein occlusion (BRVO), were observed in the retina of an HIV-infected patient with cytomegalovirus (CMV) retinitis who developed neovascularization of the disc (NVD). Although BRVO and reversible NVD have been reported in association with CMV retinitis, we have seen no reports of concomitant BRAO. CMV damages endothelial cells and causes an occlusive vasculitis. In HIV-infected individuals, damaged endothelial cells and rheologic problems result in increased blood viscosity. HIV infection has also been associated systemically with elevated levels of cytokines, including tumor necrosis factor alpha (TNF-alpha). In vitro, TNF-alpha exerts effects that decrease fibrinolytic potential; this activity in the circulation of a patient with AIDS may lead to vascular occlusive events. In the patient reported here, the retinal changes were not reversed by induction therapy with ganciclovir and the NVD did not regress.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

Atypical retinitis proliferans, retinal telangiectasis, and vitreous hemorrhage in a patient with tuberous sclerosis.

This report describes an unusual case of recurrent vitreous hemorrhage and atypical retinal neovascularization in a patient with tuberous sclerosis. During three years of observation, the patient also developed retinal telangiectasis with macular edema and lipid exudation. Although the patient did not have an obvious astrocytic hamartoma, a diffuse, flat retinal hamartoma within the nerve fiber layer was suspected.

Adult↗
PubMedDate not supplied

Fluorescein angiography--is it safe to use in a pregnant patient?

We sent questionnaires to 424 retina specialists in order to compile information on the use of fluorescein angiography in pregnant women. Four-hundred and three specialists responded. Of these, 313 (78%) had never performed fluorescein angiography on a pregnant woman. Ninety specialists (22%) had performed at least one fluorescein angiogram on a pregnant woman; detailed information was obtained on 105 patients. Authors of previous reports that included fluorescein angiography during pregnancy provided information on an additional 11 patients. Substantiated side effects were nausea and/or vomiting in seven patients. Anomalies at birth, an undescended testicle and syndactyly, were reported in two children. There was one stillbirth with pathologic findings classic for toxemia and one fetal death not related in time to fluorescein angiography. One therapeutic abortion was performed for complications in toxemia. One spontaneous abortion occurred 3 days after fluorescein angiography in a patient who was four weeks pregnant. Eight children born to toxemic mothers had low birth weights. Based on our data, we conclude that fluorescein angiography does not offer a high rate of birth anomalies or complications during pregnancy.

Adult↗