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David J Browning

Publications and source records attributed to David J Browning.

At least 19 recordsLinked to original sources
PubMed2006

Relationship between optical coherence tomography-measured central retinal thickness and visual acuity in diabetic macular edema.

OBJECTIVE: To compare optical coherence tomography (OCT)-measured retinal thickness and visual acuity in eyes with diabetic macular edema (DME) both before and after macular laser photocoagulation. DESIGN: Cross-sectional and longitudinal study. PARTICIPANTS: Two hundred ten patients (251 eyes) with DME enrolled in a randomized clinical trial of laser techniques. METHODS: Retinal thickness was measured with OCT and visual acuity was measured with the electronic Early Treatment of Diabetic Retinopathy procedure. MAIN OUTCOME MEASURES: Optical coherence tomography-measured center point thickness and visual acuity. RESULTS: The correlation coefficients for visual acuity versus OCT center point thickness were 0.52 at baseline and 0.49, 0.36, and 0.38 at 3.5, 8, and 12 months after laser photocoagulation. The slope of the best fit line to the baseline data was approximately 4.4 letters (95% confidence interval, 3.5-5.3) of better of visual acuity for every 100-mum decrease in center point thickness at baseline with no important difference at follow-up visits. Approximately one third of the variation in visual acuity could be predicted by a linear regression model that incorporated OCT center point thickness, age, hemoglobin A1C, and severity of fluorescein leakage. The correlation between change in visual acuity and change in OCT center point thickening 3.5 months after laser treatment was 0.44, with no important difference at the other follow-up times. A subset of eyes showed paradoxical improvements in visual acuity with increased center point thickening (7%-17% at the 3 time points) or paradoxical worsening of visual acuity with a decrease in center point thickening (18%-26% at the 3 time points). CONCLUSIONS: There is modest correlation between OCT-measured center point thickness and visual acuity, and modest correlation of changes in retinal thickening and visual acuity after focal laser treatment for DME. However, a wide range of visual acuity may be observed for a given degree of retinal edema. Thus, although OCT measurements of retinal thickness represent an important tool in clinical evaluation, they cannot substitute reliably as a surrogate for visual acuity at a given point in time. This study does not address whether short-term changes on OCT are predictive of long-term effects on visual acuity.

Diabetic Retinopathy↗
PubMed2006

Comparison of the magnitude and time course of macular thinning induced by different interventions for diabetic macular edema: implications for sequence of application.

PURPOSE: To determine estimates of the magnitude and time course of macular thinning induced by three interventions for diabetic macular edema (DME). DESIGN: Retrospective observational case series. PARTICIPANTS: Two hundred eleven eyes of 133 patients of a private retina practice, each diagnosed with DME in > or =1 eye. METHODS: Review of clinical charts and optical coherence tomography measurements of eyes receiving focal laser photocoagulation, intravitreal triamcinolone injection (IVTA), or vitrectomy compared to untreated fellow eyes without DME. MAIN OUTCOME MEASURES: Central subfield mean thickness (CSMT; in micrometers), total macular volume (cubic millimeters), visual acuity, and rates of increased macular thickening at follow-up. RESULTS: At 6 months follow-up, predicted change in CSMT is 0 mum for untreated fellow eyes without DME, -28 mum for eyes receiving focal laser, -83 mum for eyes receiving triamcinolone, and -92 mum for eyes receiving vitrectomy. The predicted change in Early Treatment Diabetic Retinopathy Study letters read at 6 months is 0 for untreated fellow eyes without DME, 0 for eyes receiving focal laser, +3 for eyes receiving IVTA, and -1 for eyes receiving vitrectomy. Increased thickening of the macula after interventions designed to thin it were 25.4% for focal laser, 3.8% for IVTA, and 19.0% for vitrectomy. CONCLUSIONS: Interventions for DME differ in effect size, durability of effects, and potential for subsequent increases in macular thickness. A prospective study to elucidate a preferred sequence of interventions in DME may be worthwhile.

Diabetic Retinopathy↗
PubMed2006

Diurnal variation in retinal thickening measurement by optical coherence tomography in center-involved diabetic macular edema.

OBJECTIVE: To evaluate diurnal variation in retinal thickness measured with optical coherence tomography (OCT) in patients with center-involved diabetic macular edema. METHODS: Serial OCT3 measurements were performed in 156 eyes of 96 subjects with clinically diagnosed diabetic macular edema and OCT central subfield retinal thickness of 225 microm or greater at 8 am. Central subfield thickness was measured from OCT3 retinal thickness maps at 6 points over a single day between 8 am and 4 pm. A change in central subfield thickening (observed thickness minus mean normal thickness) of at least 25% and of at least 50 microm at 2 consecutive points or between 8 am and 4 pm was considered to have met the composite outcome threshold. RESULTS: At 8 am, the mean central subfield thickness was 368 microm and the mean visual acuity was 66 letters (approximately 20/50). The mean change in relative central subfield retinal thickening between 8 am and 4 pm was a decrease of 6% (95% confidence interval, -9% to -3%) and the mean absolute change was a decrease of 13 microm (95% CI, -17 to -8). The absolute change was significantly greater in retinas that were thicker at 8 am (P<.001) but the relative change was not (P = .14). The composite threshold of reduction in central subfield thickening (as defined above) was observed in 5 eyes of 4 subjects (3% of eyes; 95% CI, 1% to 8%) while 2 eyes of 2 subjects (1%; 95% CI, 0% to 5%) had an increase in central subfield thickening of this same magnitude. The maximum decrease was observed at 4 pm in all 5 eyes. CONCLUSION: Although on average there are slight decreases in retinal thickening during the day, most eyes with diabetic macular edema have little meaningful change in OCT central subfield thickening between 8 am and 4 pm.

Anthropometry↗
PubMed2005

Clinical management of silicone intraocular lens condensation.

PURPOSE: To report a novel technique in the management of silicone intraocular lens condensation after gas-fluid exchange. DESIGN: Interventional case report. METHODS: Clinical management of an obstacle to treatment. setting: Private retina practice. patient population: One patient with silicone posterior chamber intraocular lens implant and posterior capsulotomy who subsequently experienced complicated retinal detachment. intervention: Application of a heating pad to clear intraocular lens condensation. main outcome measure: Visibility of the fundus for laser treatment. RESULTS: Application of a heating pad to the closed eyelid significantly reduced the intraocular lens condensation and provided a clear view for the surgeon to apply laser retinopexy. CONCLUSIONS: Treatment of retinal detachment is complicated by lens condensation after gas-fluid exchange in patients who have undergone silicone posterior chamber intraocular lens implantation and posterior capsulotomy. We report a simple, inexpensive, and effective method to reduce lens condensation and enable in-office examination and laser treatment.

Aged↗
PubMed2005

Regional patterns of sight-threatening diabetic macular edema.

PURPOSE: To define regional patterns of macular thickening in diabetic macular edema (DME). DESIGN: Retrospective case series. METHODS SETTING: Retina practice. PATIENT POPULATION: Fifty-two normal eyes of 48 patients and 100 eyes of 80 patients with DME. EXPERIMENTAL PROCEDURE: We measured retinal thickness for nine zones and total macular volume using the 3.5-mm display of an optical coherence tomograph (OCT). We determined the normal ranges of values for zones, and then normal ranges of values for the difference in thickness between each pair of zones, termed comparisons. main outcome measures: Frequencies of increased zonal thickness, increased total macular volume, and abnormalities in zonal comparisons. RESULTS: We found the following abnormalities: increased total macular volume 49% (49/100), increased foveal zone thickness 46% (46/100), increased inner parafoveal zone thickness (average 42.2% for the four zones), and increased outer zone thickness (average 34.3% for the four zones). Abnormal two-zone comparisons were found in 1027 of the 7200 possible comparisons (14.3%). Of these abnormal comparisons, the fovea was thicker relative to another zone in 26%; the four inner parafoveal zones were thicker relative to other zones in 8.7% to 15.2% (average 13.0%); and the four outer zones were thicker relative to other zones in 3.9% to 7.6% (average 6%). Eighty-eight percent (88/100) of the eyes chosen on clinical grounds as needing focal laser photocoagulation were detected. CONCLUSION: A broader concept of OCT abnormality, which includes abnormalities in zonal relationships, may improve automated detection of DME compared with clinical judgment.

Adult↗
PubMed2005

Ocular conditions associated with peripapillary subretinal neovascularization, their relative frequencies, and associated outcomes.

OBJECTIVE: To determine frequency and outcomes of conditions with peripapillary subretinal neovascular membranes (PSRNVMs). DESIGN: Retrospective observational case series. PARTICIPANTS: All patients from a private community-based retina practice diagnosed with a PSRNVM. METHODS: Review of clinical charts, photographs, and fluorescein angiograms of 115 eyes of 96 patients, accrued over 18 years. MAIN OUTCOME MEASURES: Demographics, visual acuity (VA), laterality, neovascular membrane type and recurrence status over treatment course, and associated ocular conditions. RESULTS: Prevalences of reported associations were 52 (45.2%), age-related maculopathy (ARM); 45 (39.1%), idiopathic; 5 (4.3%), multifocal choroiditis; 3 (2.6%), angioid streaks; 2 (1.7%), histoplasmosis; 2 (1.7%), choroidal osteoma; 1 (0.9%), optic disc drusen; and 1 (0.9%), congenital disc anomaly. Newly recognized associations include pattern dystrophy (3 [2.6%]) and peripapillary pseudopodal pigment epithelial and choroidal atrophy (1 [0.9%]). Second-eye involvement was observed in 19.8% of patients over a median follow-up of 2 years. Median initial VAs were 20/40 for ARM-associated eyes and 20/30 for idiopathic eyes (P = 0.0230). Median final VAs were 20/70 for ARM-associated eyes and 20/32 for idiopathic eyes (P = 0.0261). The VA changes in the ARM-associated and idiopathic groups did not differ significantly (P = 0.1453). Recurrence of PSRNVMs after laser ablation was seen in 14 of 73 eyes (19.2%). A case of a PSRNVM as a cause of pseudopapilledema leading to unnecessary neurological imaging is reported. CONCLUSIONS: Close inspection of fellow eyes at the time of first eye diagnosis and regular follow-up afterward are indicated, given the high rate of eventual bilateral involvement regardless of associated condition. Laser ablation of PSRNVMs with broad treatment margins reduces recurrence rates relative to earlier series. The differential diagnosis of disc edema should include PSRNVMs. Pattern dystrophy can be associated with PSRNVMs.

Adult↗
PubMed2004

Bull's-eye maculopathy associated with quinacrine therapy for malaria.

PURPOSE: To report a side effect of quinacrine therapy for malaria. DESIGN: Case report. METHODS: Review of clinical chart and photographs. SETTING: Private retina practice. RESULTS: A patient developed a bilaterally symmetric bull's-eye maculopathy 45 years after taking quinacrine for 18 months as prophylaxis against malaria. Progression of the clinical picture was documented over 15 years of follow-up. The clinical picture was identical to that of chloroquine and hydroxychloroquine maculopathy. CONCLUSIONS: Low dosages of quinacrine used for malaria prophylaxis can be associated with a delayed, severe maculopathy indistinguishable from chloroquine maculopathy in certain patients.

Antimalarials↗
PubMed2004

Optical coherence tomography to detect macular edema in the presence of asteroid hyalosis.

PURPOSE: To propose the use of optical coherence tomography as an effective diagnostic tool for identifying macular edema in patients with asteroid hyalosis obscuring the fundus view. DESIGN: Case report. METHODS: Review of clinical chart and images. SETTING: Private retina practice. PATIENT: One patient diagnosed with diabetic retinopathy and asteroid hyalosis, who was experiencing decreased visual acuity and whose fundus view was inadequate for diagnosis using customary techniques. RESULTS: Usual methods of diagnosis were ineffective until OCT obtained a clear image of the fundus and subsequent macular thickening with vitreomacular adhesion. CONCLUSIONS: Optical coherence tomography is an effective diagnostic tool for discovering macular edema in cases of dense asteroid hyalosis where traditional methods fail to obtain a clear image of the fundus.

Aged↗
PubMed2004

Interobserver variability in optical coherence tomography for macular edema.

PURPOSE: To assess the interobserver variability of optical coherence tomography (OCT) measurements in patients with macular edema. DESIGN: Noninterventional case series using a diagnostic instrument. METHODS: Ordinary least products analysis of OCT data obtained by two masked observers from a set of 20 eyes from 10 patients. SETTING: Private retina practice. RESULTS: Foveal zone thickness measurements were operator dependent. Fixed and proportional bias was found between the two observers. Total macular volume measurements were independent of observers. CONCLUSION: Foveal zone thickness measurements are not directly comparable across different observers, but total macular volume measurements are directly comparable. Multicenter studies involving OCT measurements and clinical users of OCT data will need to factor interobserver variability into conclusions drawn from pooled OCT foveal zone thickness measurements.

Humans↗
PubMed2004

Intraobserver variability in optical coherence tomography.

PURPOSE: To assess the intraobserver variability of optical coherence tomography (OCT) in patients with clinically stable maculas. DESIGN: Retrospective, observational case series using a diagnostic instrument. METHODS: Retrospective study. setting. Private retina practice. patient population. Twenty-two eyes of 19 patients, each studied twice within 4 months. observation procedure. Optical coherence tomograph measurements of the macula obtained by two photographers. main outcome measures. Ordinary least products (OLP) and Bland-Altman analysis of OCT data. RESULTS: No fixed or proportional bias was detected in foveal zone thickness and total macular volume between measurements of either of the OCT operators. The coefficient of repeatability for foveal zone thickness was 37.0 microm for photographer 1 and 34.8 microm for photographer 2. The coefficient of repeatability for total macular volume was 0.29 mm(3) for photographer 1 and 0.10 mm(3) for photographer 2. CONCLUSION: Foveal zone thickness and total macular volume measurements show low intraobserver variability when analyzed by OLP and Bland-Altman techniques. Bounds are given for foveal zone thickness and total macular volume for which longitudinal OCT measurements by the same operator can be considered to reflect natural history or intervention effects rather than intraobserver variability.

Diagnostic Techniques, Ophthalmological↗
PubMed2004

Comparison of the clinical diagnosis of diabetic macular edema with diagnosis by optical coherence tomography.

PURPOSE: To compare the diagnosis of diabetic macular edema (DME) by stereoscopic slit-lamp biomicroscopic examination of the fundus with a 78-diopter noncontact lens with diagnosis by optical coherence tomography (OCT). DESIGN: Prospective, double-masked, noninterventional diagnostic study. METHODS: Analysis of slit-lamp biomicroscopic findings compared with OCT measurements. PARTICIPANTS: Patients with DME from a private retina practice. MAIN OUTCOME MEASURES: Presence or absence of macular thickening. RESULTS: The reference range for this clinic was comparable to reference ranges published from other clinics. The clinical detection of DME was less than detection by OCT. Chance-corrected agreements (kappa statistic) of the 2 methods were 0.63 for the foveal zone and 0.36 to 0.42 for the 4 parafoveal zones. The errors committed in clinical examination were primarily of the type in which clinical examination did not detect DME but OCT did (58%-90%) for the 5 zones analyzed. CONCLUSIONS: Reference ranges for OCT seem to be similar for different clinical settings, suggesting the usefulness of OCT in multicenter studies. The current standard of care for DME detection, stereoscopic slit-lamp examination of the fundus, is less sensitive than OCT for detection of DME. Because the principal therapy for DME, focal laser photocoagulation, is mainly sight preserving and not sight restoring, the wider use of OCT may beneficially impact visual disability from DME.

Diabetic Retinopathy↗
PubMed2004

West African crystalline maculopathy.

OBJECTIVE: To report new observations in West African crystalline maculopathy. DESIGN: Retrospective, observational case series. PARTICIPANTS: Three patients drawn from a private retina practice. METHODS: Review of clinical charts and photographic studies. MAIN OUTCOME MEASURES: Distribution of intraretinal crystals and changes after laser photocoagulation, and history of ingesting foods typical in a West African diet but atypical for an American diet. RESULTS: All patients were older than 50 years, had diabetic retinopathy, ate green vegetables not found in American diets, and showed no deleterious effects of the crystals. Kola nut ingestion in 2 patients was remote and sparse, and was unknown in a third patient. The first 2 affected patients originating outside the Ibo tribe of Nigeria are reported. The pattern of retinal crystals can be changed, and the quantity of crystals reduced, by laser photocoagulation of associated diabetic retinopathy. CONCLUSIONS: West African crystalline retinopathy is distinguishable from other causes of crystalline retinopathy. It may reflect a component of the West African diet, seems to have diabetic retinopathy as a promoting factor via breakdown of the blood-retina barrier, and can be modified by laser photocoagulation of diabetic retinopathy. Increased awareness of the condition will allow physicians seeing West African immigrants to make the diagnosis and treat the patients appropriately.

Aged↗
PubMed2004

Retinal vein occlusions in patients taking warfarin.

OBJECTIVE: To describe development of retinal vein occlusion (RVO) in patients anticoagulated with warfarin. DESIGN: Retrospective, observational case series. PARTICIPANTS: Thirteen patients drawn from a private retina practice. METHODS: Review of clinical records, laboratory results, color fundus photographs, and fluorescein angiograms. MAIN OUTCOME MEASURES: Primary measures were international normalized ratio (INR), visual acuity, and concurrent systemic disease. RESULTS: The female-to-male ratio was 7 to 6. Age range was 44 to 86 years, with a median age of 73 years. Two patients had systemic lupus erythematosus, 7 had hypertension, and 2 had primary open-angle glaucoma. Two had laboratory abnormalities: 1 with a combination of lupus anticoagulant and anticardiolipin antibodies and 1 with a combination of hyperhomocystinemia and low antithrombin III. Three patients were taking acetylsalicylic acid in addition to warfarin at the time of the RVO. The INRs at the time of RVO were 0.9 to 3.8, with 9 of 13 <==2.0. CONCLUSIONS: Anticoagulation with warfarin does not preclude RVO in predisposed patients, nor does combination therapy with warfarin and acetylsalicylic acid. Attention to keeping the INR >2.0 may be helpful.

Adult↗
PubMed2004

Positioning the obese or large-breasted patient for macular laser photocoagulation.

PURPOSE: To report a positioning method for macular laser photocoagulation in obese or large-breasted patients. DESIGN: Report of a laser technique. METHODS: Review of clinical experience. SETTING: Private retina practice. RESULTS: Standing the patient up, leaning forward, and using the examination chair as buttocks support allows easier positioning of the obese or large-breasted patient in the slit lamp. The laser surgeon's hand manipulating the slit-lamp joystick does not fatigue, which allows more careful examination and treatment in these delicate cases. CONCLUSIONS: The technique described may allow more thorough diagnostic evaluation and focal laser treatment of obese and large-breasted patients with macular diseases.

Breast↗
PubMed2003

Iris cyst secondary to latanoprost mimicking iris melanoma.

PURPOSE: To report an ocular side effect of topical latanoprost therapy. DESIGN: Single interventional case report. METHODS: A 73-year-old woman on latanoprost for primary open-angle glaucoma developed an iris cyst simulating an iris melanoma. RESULTS: The lesion disappeared over 8 weeks when latanoprost was stopped. CONCLUSIONS: In managing patients with iris-pigmented lesions, the list of medications should be reviewed. If the patient takes latanoprost, a trial off latanoprost is warranted.

Aged↗