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Biomedical subjects

D R Guyer

Publications and source records attributed to D R Guyer.

At least 55 records · Page 3Linked to original sources
PubMed1992

Subretinal fibrosis after laser photocoagulation for diabetic macular edema.

Seven eyes had subretinal fibrosis after grid laser photocoagulation for diabetic macular edema. The fibrosis caused persistent loss in visual acuity, and in six of the seven eyes, was not associated with detectable laser-induced Bruch's membrane rupture or subretinal hemorrhage. Choroidal neovascularization was detected in only one patient, who was notably younger (27 years) than the median age of 70 years in this series. The median preoperative visual acuity was 20/80 (range, 20/40 to 20/400); the median postoperative visual acuity was 20/400 (range, 20/80 to counting fingers). The subretinal fibrosis was detected at a median of three months (range, 14 days to 4 1/2 months) after laser therapy. In one of five bilaterally treated patients (20%), subretinal fibrosis developed in both eyes. Subretinal fibrosis may be caused by undetected choroidal neovascularization or by excessive proliferation after stimulation of an aged retinal pigment epithelium. Subretinal fibrosis may be a potential cause of loss in visual acuity after laser treatment for diabetic macular edema.

Adult↗
PubMed1992

Observations on patients with idiopathic macular holes and cysts.

We reexamined 96 patients with macular holes or cysts. The mean follow-up period was 4.7 years. Of 19 eyes with macular cysts, only two (10.5%) showed progression to a macular hole. In 15 (79%) of those 19 eyes, the cyst disappeared. Of 80 patients with a macular hole or cyst in one eye and a normal fellow eye, a hole developed in the fellow eye in only one patient (1.2%) and a cyst developed in the fellow eye in only two patients (2.5%). Of 66 eyes with a stage 3 full-thickness macular hole, three eyes (5%) showed resolution without any sign of a hole. Our results suggest a favorable prognosis for normal fellow eyes of patients with macular holes or cysts and for eyes with cysts. Eyes with full-thickness macular holes have a less favorable prognosis, although their natural history may not be as poor as previously thought.

Adult↗
PubMed1992

Radiation maculopathy after proton beam irradiation for choroidal melanoma.

PURPOSE: Radiation maculopathy is a microangiopathy of the retina, which is often observed after irradiation of the eye. To quantitatively determine the frequency of anatomic and functional features of this condition, the authors reviewed a large series of patients with choroidal melanomas who were treated by proton beam irradiation. METHODS: Color photographs and/or fluorescein angiograms of 218 patients with paramacular choroidal melanomas were graded by two independent masked readers to determine the frequency of the various lesions of radiation maculopathy. RESULTS: Overall, 194 (89%) of the 218 patients in this study developed some degree of radiation maculopathy. The earliest and most common finding was macular edema, which was observed in 87% of patients, overall, by the end of year 3. Microvascular changes (microaneurysms and/or telangiectasia), intraretinal hemorrhages, and capillary nonperfusion were noted in 76%, 70%, and 64% of eyes, respectively, by the end of postirradiation year 3. Visual acuity was retained at 20/200 or better in 90% of eyes 1 year after irradiation and in 67% of eyes 3 years after treatment. CONCLUSION: Radiation maculopathy is common after proton beam irradiation of paramacular choroidal melanomas. However, ambulatory vision is preserved in many eyes.

Adolescent↗
PubMed1992

Penetrating ocular fish-hook injuries. Surgical management and long-term visual outcome.

BACKGROUND: Ocular penetrating fish-hook injuries represent a rare yet potentially devastating ocular trauma. To date, only five cases have been reported in the medical literature. The authors present five new cases with long-term follow-up. METHODS: All individuals who presented to the Wilmer Ophthalmological Institute emergency room with ocular fish-hook injuries between 1974 and 1990 were identified, and ophthalmic follow-up evaluations were performed. RESULTS: Individuals were male, between the ages of 10 and 27, with follow-up evaluation of 2.0 to 15.5 years (mean, 6.7 years). The left eye was involved in 80% and in no instance had a single hook penetrated the lid and globe simultaneously. Initial visual acuity was uniformly poor (20/200 or worse). Using specialized surgical techniques, ultimate visual outcome was excellent in 80% of cases (4 of 5 with visual acuity of 20/30 or better). One eye was enucleated because of panendophthalmitis after delayed wound closure. Similar overall results are achieved when previous reports are included in the analysis (90% with visual acuity of 20/40 or better). CONCLUSIONS: These results suggest that penetrating ocular fish-hook injuries may have an excellent long-term prognosis if prompt, appropriate surgical intervention is accomplished.

Adolescent↗
PubMed1992

Digital indocyanine-green angiography in chorioretinal disorders.

The authors performed digital indocyanine-green angiography in 37 patients with chorioretinal disorders. Eighteen patients had choroidal neovascularization, 7 patients had atrophic age-related maculopathy, and 12 patients had uncommon choroidal and retinal disorders. A Topcon indocyanine-green camera was integrated with a digital (1024-line resolution) angiography system. Compared with conventional video or photographic indocyanine-green angiography, this technique offers enhanced image resolution, the possibility of direct qualitative comparison with fluorescein angiography, image archiving, hard-copy generation, and tracing capabilities to plan laser treatment strategies and monitor the adequacy of laser therapy after surgery.

Choroid Diseases↗
PubMed1992

Digital indocyanine green videoangiography and choroidal neovascularization.

This report describes a new system for digital indocyanine green videoangiography (ICGV) that provides enhanced imaging of the choroidal circulation. This newly assembled system was used to study a consecutive series of 129 patients with exudative age-related macular degeneration (AMD), and ill-defined or occult choroidal neovascularization (CNV). Overall, 39% of the patients in this study with occult CNV could be reclassified as having well-delineated or so-called classic CNV by virtue of the additional findings provided by ICGV. In this series, ICGV was particularly useful in identifying occult CNV in eyes with a large, serous pigment epithelial detachment (PED) and in eyes with recurrent CNV after previous laser photocoagulation treatment. Some of these patients were selected for laser photocoagulation of the abnormal choroidal vessels in order to evaluate the feasibility of this form of treatment on the basis of combined clinical, fluorescein angiographic, and ICGV findings. The results of this study suggest that ICGV is an important adjunct in the evaluation, classification, and laser treatment of patients with occult CNV secondary to AMD.

Aged↗
PubMed1992

Dislocation of the crystalline lens in a patient with Sturge-Weber syndrome.

A moderately retarded institutionalized patient diagnosed with Sturge-Weber syndrome and bilateral retinitis pigmentosa underwent enucleation OD because of intractable pain secondary to glaucoma in 1965. Twenty-three years later, the patient had a dislocated lens OS. Although the lens dislocation might have been caused by trauma, it also might be associated with either Sturge-Weber syndrome or retinitis pigmentosa. The role of protective eye wear in one-eyed institutionalized retarded patients is discussed. To our knowledge, this combination of Sturge-Weber syndrome, bilateral retinitis pigmentosa, and a dislocated lens has not been reported previously.

Cataract↗
PubMed1990

Histopathologic features of idiopathic macular holes and cysts.

The pathogenesis of idiopathic macular holes and cysts is currently debated. The authors studied the histopathologic features of 41 specimens. Of 22 full-thickness holes, 16 (73%) had epiretinal membranes (ERMs), 15 (68%) had cystoid macular edema (CME), and 3 (17%) were sealed by fibroglial and retinal pigment epithelial hyperplasia. Photoreceptors were variably degenerated, for a mean of 480 microns (range, 200-750 microns) from the hole margins. Of 12 lamellar macular holes, 6 (50%) had an ERM exhibiting tangential traction on the internal limiting membrane. Cystoid macular edema was present in five (71%) of seven macular cysts, and an ERM was noted in only one (14%). The authors' results suggest that ERM tangential traction may play a role in the pathogenesis of lamellar macular holes. Macular holes often have associated ERMs and CME, which may be potentially reversible.

Aged↗
PubMed1990

Bilateral ischemic optic neuropathy and retinal vascular occlusions associated with lymphoma and sepsis. Clinicopathologic correlation.

The authors report the clinicopathologic correlation of a patient with non-Hodgkin's mixed-cell lymphoma who had impairment of the circulation of the optic nerve and retina in both eyes. The results of histopathologic examination showed that the pial septa of the optic nerves were infiltrated by lymphoma and that there was extensive infarction of the orbital portions of both optic nerves and occlusion of both central retinal arteries and the right central retinal vein by thrombi with bacteria. The infiltration of the optic nerves seemed to be resistant to therapy.

Bacterial Infections↗
PubMed1989

Ophthalmic manifestations of leukemia.

We prospectively examined the eyes of 120 patients with leukemia. Only 38% of patients had normal results of examination. Leukemic infiltrates were present in 3% of patients, other findings related to leukemia were seen in 39% of patients, and 20% of patients had unrelated abnormalities. Visual loss was seen in at least 5% of the patients in this study.

Adolescent↗
PubMed1989

Regression of cytomegalovirus retinitis with zidovudine. A clinicopathologic correlation.

A 55-year-old man with the acquired immunodeficiency syndrome had cytomegalovirus (CMV) retinitis develop in his left eye. The patient declined treatment with ganciclovir but elected to be treated with zidovudine. Two months later his CMV retinitis regressed, and it remained inactive for a total of 9 months. The most likely explanation was zidovudine-mediated improvement in the patient's immune function with subsequent suppression of the CMV retinitis in the left eye. The patient ultimately and preterminally had CMV retinitis develop in his right eye. He subsequently died and his eyes were examined at autopsy. Active CMV retinitis lesions were noted in the right eye while inactive scars were noted in the left eye. Immunoperoxidase staining and in situ hybridization studies demonstrated the presence of CMV in the right eye but not in the left eye. While ganciclovir remains the treatment of choice for CMV retinitis, zidovudine treatment may have a beneficial effect on CMV retinitis in some patients.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Leukemic retinopathy. Relationship between fundus lesions and hematologic parameters at diagnosis.

The authors examined 117 consecutive patients with acute leukemia within a few days of diagnosis. Sixty-six patients had acute nonlymphocytic leukemia, and 51 had acute lymphocytic leukemia. Forty-two percent of the patients had abnormal ocular findings related to leukemia. The authors found an association between the presence of intraretinal hemorrhages and thrombocytopenia for all patients. In addition, patients with acute lymphocytic leukemia and intraretinal hemorrhages had lower hematocrit levels than did those without such hemorrhage. The presence of anemia was related to the findings of white-centered hemorrhages in patients with acute nonlymphocytic leukemia. The presence of cotton-wool spots was not associated with hematologic parameters. Intraretinal hemorrhages, white-centered hemorrhages, and cotton-wool spots were all found more frequently in adults than in children.

Adolescent↗
PubMed1987

Terrien's marginal degeneration: clinicopathologic case reports.

We report the clinicopathologic features of seven cases of Terrien's marginal degeneration. Three specimens studied were lamellar resections and four were full-thickness corneal segments. Of the four full-thickness specimens, three were semilunar and one was an annular ("doughnut-shaped") specimen. All cases had stromal thinning, vascularization, lipid keratopathy and local absence of Bowman's membrane. Descemet's membrane was markedly thickened and the endothelium was intact. Three of the four full-thickness corneal specimens showed healed ruptures of Descemet's membrane. One specimen had four healed successive ruptures in Descemet's membrane in the same area. The corneal endothelium in that area had produced a basement membrane that totalled 35 micron in thickness. The clinical and histopathologic features of pellucid and Terrien's marginal degeneration are similar. When idiopathic peripheral corneal thinning remains clear, it is regarded as pellucid degeneration; vascularization, scarring, and lipid keratopathy are regarded as Terrien's marginal degeneration. Breaks in Descemet's membrane contribute to these latter changes.

Basement Membrane↗
PubMed1986

Subfoveal choroidal neovascular membranes in age-related macular degeneration. Visual prognosis in eyes with relatively good initial visual acuity.

We determined the visual prognosis of 94 eyes in 92 patients having age-related macular degeneration, a discrete choroidal neovascular membrane directly under the center of the foveal avascular zone (subfoveal), and an initial visual acuity of 20/100 or better. Of the patients who were reexamined 24 months following their initial presentation, 77% had lost at least four lines of vision and 64% had lost at least six lines. Estimation of visual loss using a conservative assessment procedure showed four-line visual loss in 65% of the patients and six-line loss in 50%. In general, the better the visual acuity at the initial examination, the more likely the patient was to have a smaller choroidal neovascular membrane. These results suggest that it may be reasonable to consider a randomized clinical trial of laser photocoagulation for this group of patients with a relatively poor visual prognosis.

Age Factors↗