Quantitative assessment of macular edema with retinal vein occlusion

Topographic patterns of retinal edema in eyes with branch retinal vein occlusion and their association with macular edema recurrence

In this study, we evaluated the topographic pattern of retinal edema in eyes with macular edema (ME) secondary to branch retinal vein occlusion (BRVO) using a widefield retinal thickness map of optical coherence tomography and its association with ME recurrence. In 87 eyes with ME secondary to BRVO who were treated with anti-vascular endothelial growth factor (VEGF) injections and followed up for ≥ 1 years, 12 × 9 mm macular volume scans of swept-source optical coherence tomography (DRI-OCT Triton; Topcon Inc, Japan) were performed and retinal thickness maps were automatically generated at baseline and follow-up visits. Topographic patterns of retinal edema on the maps at baseline and 1 month after the first anti-vascular endothelial growth factor (VEGF) treatment were classified as extramacular (outside the ETDRS grid), macular (within the grid), and combined pattern and correlated with ME recurrences. Seventy-five of 87 (86.2%) eyes with BRVO ME showed combined edema at baseline. There were 4 topographic patterns of edema at 1 month following anti-VEGF injection as follows: no residual edema, extramacular only, macular only, and combined edema. In contrast to the baseline pattern, the pattern of retinal edema 1 month following anti-VEGF therapy showed significant association with 6-month recurrence, number of ME recurrences during a 1-year period, and time to first recurrence. (all P < 0.05) An automatically generated widefield retinal thickness map could be used to effectively visualize the topographic patterns of retinal edema in eyes with BRVO. The map can be used as a valuable tool for detection of retinal edema on widefield retinal areas and prediction of ME recurrence in eyes with BRVO.

Relationship Between Visual Acuity and Retinal Thickness During Anti-Vascular Endothelial Growth Factor Therapy for Retinal Diseases

PURPOSE

To investigate the relationship between best-corrected visual acuity (BCVA) and central retinal thickness (CRT) in eyes receiving ranibizumab for 3 common retinal diseases.

DESIGN

Retrospective analysis of clinical trial data.

METHODS

Early Treatment Diabetic Retinopathy Study BCVA and spectral-domain optical coherence tomography-measured CRT of 387 eyes of 345 patients enrolled in 6 prospective clinical trials for management of neovascular age-related macular degeneration (AMD), diabetic macular edema (DME), and retinal vein occlusion (RVO) were evaluated by Pearson correlation and linear regression.

RESULTS

At baseline, there was a small correlation between BCVA and CRT in pooled AMD trial data (r = -0.24). A medium correlation was identified in pooled DME trial data (r = -0.42). No correlation was found in pooled RVO trial data. At month 12, no correlation was found between changes from baseline in BCVA and CRT in pooled AMD trial data. Medium correlations were identified in both pooled DME (r = -0.45) and pooled RVO (r = -0.35) trial data at month 12. Changes in BCVA and CRT associated with edema recurrence upon transition from monthly to pro re nata (PRN) dosing were correlated in AMD (r = -0.27) and RVO (r = -0.72) trials, but not in DME trial data.

CONCLUSION

DME demonstrated a convincing relationship between BCVA and CRT. Correlations appear to be more complex in AMD and RVO. At the inflection point between monthly and PRN dosing, when recurrence of edema is anticipated in many patients, CRT appears strongly correlated with loss of BCVA in RVO.

Quantitative Optical Coherence Tomography Angiography Features and Visual Function in Eyes With Branch Retinal Vein Occlusion

PURPOSE

To measure the vascular density and foveal avascular zone (FAZ) area in the deep and superficial retinal vascular networks using optical coherence tomography angiography (OCTA) in patients with branch retinal vein occlusion (BRVO).

DESIGN

Retrospective observational case series.

METHODS

Patients with unilateral BRVO involving the macula were enrolled. OCTA was performed on the BRVO and fellow eyes. Macular vascular density, FAZ area, and foveal thickness were measured in all eyes.

RESULTS

Seventeen eyes of 17 patients met inclusion criteria. The mean overall vascular density measured in the entire scan was lower in BRVO eyes compared to fellow eyes in both the superficial (48.07% vs 52.60%, respectively; P < .001) and deep (52.60% vs 57.67%, respectively; P < .001) networks. In both networks, the density was lower in the affected BRVO sector compared to the unaffected sector in the same eye and in the fellow eye (P < .001). In the deep network, the density was lower in the unaffected sector of the BRVO eye compared with the corresponding sector in the fellow eye (58.87% vs 61.65%, respectively; P = .04). A negative correlation was found between the logarithm of the minimal angle of resolution (logMAR) visual acuity and the overall density in superficial (r = -0.40, P = .02) and deep (r = -0.38, P = .03) networks. The mean FAZ area in BRVO eyes was significantly lower only at the level of the deep network when compared to the fellow eyes (0.519 mm(2) vs 0.410 mm(2), respectively; P = .02) and correlated positively with logMAR (r = 0.34, P = .04).

CONCLUSION

In eyes with BRVO, quantitative OCTA measurements confirm decreased vascular density in both the superficial and deep vascular networks. Moreover, vascular density and FAZ area appear to correlate with visual function.

Macular edema in central retinal vein occlusion: correlation between optical coherence tomography, angiography and visual acuity

To analyze the characteristics and the course of macular edema secondary to central retinal vein occlusion (CRVO) using optical coherence tomography (OCT) and to determine correlations between clinical, tomographic and angiographic data, in particular including retinal ischemia. In this retrospective study, 53 consecutive patients with CRVO were included. At each follow-up visit, patients underwent complete ophthalmological examination, including best-corrected visual acuity (BCVA) and OCT. Fluorescein angiography was performed at baseline and on demand during follow-up. 243 OCTs were analyzed. Mean age was 61 years and mean follow-up 13 months. The first structural change, observed very early after the onset of the occlusion, was a diffuse increase at the level of the outer nuclear layer without change at the level of the inner retina. This early change seemed characteristic of retinal vein occlusion. Cystoid spaces were subsequently observed in all retinal layers and were combined with serous retinal detachment in 51 %. During the first 6 months, central retinal thickness was higher in ischemic CRVO (mean, 691 μm) than in non-ischemic CRVO (mean, 440 μm, p < 0.01). In eyes with foveal thickness (central retinal thickness without subretinal fluid) of 700 μm or greater, peripheral ischemia was present in 69 % of eyes, final BCVA was 20/200 or less in 75 % and never reached 20/40 during follow-up. The integrity of the junction of the photoreceptors' inner and outer segments was correlated with a better prognosis (p < 0.05). Foveal thickness was inversely correlated to BCVA at each visit and could have a prognostic value. OCT examination in CRVO revealed useful data for the diagnosis of CRVO and its prognosis. The largest macular edemas seemed to be the hallmark of ischemic CRVO.

Pars plana vitrectomy and internal limiting membrane peeling for macular edema secondary to retinal vein occlusion

Purpose:

To evaluate the effects of vitrectomy and internal limiting membrane peeling for treatment of macular edema secondary to retinal vein occlusion (RVO).

Methods:

Nine cases of visual loss due to macular edema caused by central retinal vein occlusion or branch retinal vein occlusion underwent pars plana vitrectomy with removal of the preretinal hyaloid, peeling of the internal limiting membrane stained with indocyanine green dye, air–fluid exchange, and postoperative prone positioning. Best-corrected visual acuity (BCVA) and central foveal thickness by optical coherence tomography were measured pre- and postoperatively then compared to assess the outcome of surgery.

Results:

In all cases intraretinal blood and retinal thickening diminished within 2 months of surgery. Visual acuity improved in all of the central retinal vein occlusion cases and 3/6 branch retinal vein occlusion cases. The decrease in macular thickness was statistically significant (mean postoperative macular thickness 361 ± 61.1 versus mean preoperative macular thickness 563.9 ± 90.0, P = 0.001, t-test). The improvement in BCVA was not statistically significant (mean preoperative BCVA in LogMAR 1.23 ± 0.29 versus mean postoperative BCVA in LogMAR 1.06 ± 0.49, P = 0.09, t-test).

Conclusion:

In eyes with macular edema secondary to RVO, pars plana vitrectomy with internal limiting membrane peeling can resolve macular edema, but the improvement in BCVA was not statistically significant in this study.

Influence of ischemia on visual function in patients with branch retinal vein occlusion and macular edema

Visual function and retinal morphology were investigated to elucidate the influence of ischemia in patients with branch retinal vein occlusion (BRVO) and macular edema. In 41 consecutive patients with BRVO aged 68.9 ± 10.0 years (22 women and 19 men), the area of capillary nonperfusion was measured by fluorescein angiography. Retinal thickness and retinal volume were measured by optical coherence tomography, and mean retinal sensitivity was calculated for each of 9 macular subfields. Mean visual acuity and macular sensitivity within the central subfield were not significantly correlated with the nonperfused area. However, the macular sensitivity within the central 5 subfields and all 9 subfields showed significant negative correlations with the nonperfused area. Also, macular thickness and volume within all 9 subfields were significantly correlated with the nonperfused area. In conclusion, evaluation of both the fovea and the entire macular region may be important in patients with ischemic BRVO.

Visual prognosis and vitreous molecules after vitrectomy for macular edema with branch retinal vein occlusion

This study investigated whether vascular endothelial growth factor (VEGF), soluble intercellular adhesion molecule-1 (sICAM-1), and pigment epithelium-derived factor (PEDF) influence the visual prognosis of patients with macular edema and branch retinal vein occlusion (BRVO). In 47 consecutive patients (47 eyes) undergoing vitrectomy, retinal thickness was examined by optical coherence tomography. Best-corrected visual acuity and the vitreous fluid levels of VEGF, sICAM-1, and PEDF were also determined. Patients were followed for at least 6 months after surgery. Vitreous fluid levels of VEGF and sICAM-1 were significantly lower in the patients with more marked improvement of visual acuity after vitrectomy, while PEDF was significantly higher. VEGF and sICAM-1 levels were significantly higher in patients with greater postoperative improvement of macular edema, while PEDF was significantly lower. In BRVO patients, vitreous fluid levels of VEGF, sICAM-1, and PEDF may influence both the response of macular edema to vitrectomy and the visual prognosis.

Influence of macular microcirculation and retinal thickness on visual acuity in patients with branch retinal vein occlusion and macular edema

PURPOSE

To investigate perifoveal capillary blood flow velocity and retinal thickness at the central fovea in patients with branch retinal vein occlusion (BRVO) and macular edema and to assess their relation with visual acuity and visual prognosis.

METHODS

Eighteen patients with BRVO and 16 healthy volunteers were compared. Perifoveal capillary blood flow velocity was measured on fluorescein angiograms with a scanning laser ophthalmoscope by the tracing method. Retinal thickness was measured at the central fovea by optical coherence tomography. Best-corrected visual acuity (BCVA) was determined.

RESULTS

BCVA differed significantly between patients and controls (P < 0.0001). Among patients, BCVA was negatively correlated with perifoveal capillary blood flow velocity by univariate analysis (r = -0.7916, P < 0.0001), and positively correlated with retinal thickness at the central fovea (r = 0.8970, P < 0.0001). Multivariate analysis showed that retinal thickness at the central fovea was the only independent determinant of BCVA (P < 0.0001).

CONCLUSIONS

In patients with BRVO, BCVA was more strongly influenced by retinal thickness at the central fovea than by perifoveal capillary blood flow velocity.

Visual acuity and foveal thickness after vitrectomy for macular edema associated with branch retinal vein occlusion: a case series

Background

The mechanism by which vitrectomy improves macular edema in patients with branch retinal vein occlusion remains unclear, although intraocular levels of vascular endothelial growth factor have been suggested to influence the visual prognosis and macular edema.

Methods

A series of 54 consecutive patients (54 eyes) with branch retinal vein occlusion was studied prospectively. All patients underwent pars plana vitrectomy for treatment of macular edema. Best corrected visual acuity and retinal thickness (examined by optical coherence tomography) were assessed before and after surgery. The level of vascular endothelial growth factor in vitreous fluid harvested at operation was determined. Patients were followed for at least 6 months postoperatively.

Results

Both the visual acuity and the retinal thickness showed significant improvement at 6 months postoperatively (P = 0.0002 and P < 0.0001, respectively). The vitreous level of vascular endothelial growth factor was significantly higher in patients who showed less improvement of visual acuity compared with those who had a better visual prognosis (p = 0.0135). In contrast, a high vitreous level of vascular endothelial growth factor was associated with greater improvement of macular edema (p = 0.0064).

Conclusions

These results suggest that the vitreous level of vascular endothelial growth factor might influence the visual prognosis and the response of macular edema to vitrectomy in patients with branch retinal vein occlusion.

Posterior pole retinal thickness measurements by the retinal thickness analyzer in healthy Chinese subjects

PURPOSE

To assess retinal thickness at the posterior pole in healthy Chinese subjects with the retinal thickness analyzer (RTA).

METHODS

Retinal thicknesses at the posterior pole and fovea were measured by the RTA in 331 eyes of 178 healthy Chinese subjects. Retinal thicknesses as a function of sex, age, refractive errors, and axial length were also evaluated.

RESULTS

The average thickness of the foveal area +/- SD was 158.6 +/- 24.8 microm, the average thickness of the perifoveal region (600-2,500 microm from fovea) +/- SD was 174 +/- 25.2 microm, and the average thickness of the posterior pole region (600-6,000 microm from fovea) +/- SD was 171.9 +/- 25.3 microm. There was no significant difference in retinal thicknesses of the foveal, perifoveal, and posterior pole regions in either right or left eyes or as a function of different spherical equivalents. Moreover, there was no significant difference of foveal thickness between males and females. Greater retinal thicknesses of the foveal, perifoveal, and posterior pole regions were associated with age of older than 40 years and axial length of < 24 mm, and greater perifoveal and posterior pole thicknesses were found for females. Furthermore, there were no significant correlations between age, refractive errors, and axial lengths with retinal thicknesses.

CONCLUSION

Retinal thicknesses of the posterior pole region differed by age, axial length, and sex, but there was no effect of laterality or different spherical equivalents. The RTA is a fast and noninvasive technology to assess retinal conditions with thickening or thinning in the fovea and posterior pole.

Characterization of macular edema from various etiologies by optical coherence tomography

PURPOSE

To use optical coherence tomography (OCT) to characterize the intraretinal changes associated with macular edema (ME) according to its etiology.

DESIGN

Observational case series.

METHODS

Seventy-eight eyes of 78 patients with ME were examined retrospectively by OCT, using the Humphrey 2000 OCT system (Humphrey Co., San Leandro, California). ME etiologies were diabetic retinopathy (27 cases), central retinal vein occlusion (18 cases), pseudophakia (15 cases), posterior uveitis (10 cases), and retinitis pigmentosa (eight cases). Macular thickness was measured using OCT mapping software. It was correlated with logarithmic visual acuity.

RESULTS

In 72 of 78 cases (92%), ME was located in the outer retinal layers. Serous retinal detachment was present in 29 of 78 cases (37%). It was most frequent in central retinal vein occlusion (10 of 18 cases, 56%). There were no significant differences in visual acuity (P = .26) or macular thickness (P = .95) whether or not serous retinal detachment was combined with ME. The posterior hyaloid was partially detached in 17 of 78 cases (22%) of overall cases. Serous retinal detachment did not correlate with partial posterior hyaloid detachment (P = .6). Mean macular thickness ranged from 506 microm in central retinal vein occlusion to 373 microm in retinitis pigmentosa. Visual acuity correlated with macular thickness in diabetic retinopathy (R = 0.55; P = .0027) and pseudophakia cases (R = 0.66; P = .016).

CONCLUSIONS

OCT characterized the retinal morphologic changes associated with ME, especially the vitreomacular relationship and sub-clinical serous macular detachment. This detachment did not correlate with poor visual acuity. Macular thickening only correlated with visual loss in diabetic retinopathy and pseudophakia.

Intravitreal triamcinolone acetonide for treatment of persistent macular oedema in branch retinal vein occlusion

BACKGROUND

To evaluate the efficacy of intravitreal triamcinolone acetonide injection on persistent macular oedema in branch retinal vein occlusion that fails to respond to previous laser photocoagulation.

MATERIAL AND METHODS

A total of 19 eyes of 19 patients with persistent macular oedema due to branch retinal vein occlusion were treated with 8 mg/0.2 ml of intravitreal triamcinolone acetonide injection. The main outcome measures included best-corrected visual acuity, intraocular pressure, and macular oedema map values of Heidelberg Retinal Tomograph II (HRT II) before and after intravitreal triamcinolone injection.

RESULTS

The mean follow-up time was 6.2+/-1.0 months. The mean baseline best-corrected logarithm of minimal angle of resolution (LogMAR) value for visual acuities of the patients before intravitreal triamcinolone injection was 1.01+/-0.16. After treatment, it was 0.55+/-0.22 at the 1-month, 0.56+/-0.22 at 3-month, and 0.62+/-0.22 at the last visits and the differences were statistically significant when compared with baseline values (for each, P<0.001). The mean oedema map values on HRT II significantly decreased by 28.5% at 1-month, 23.8% at 3-month, and 23.8% at the last visit when compared with preinjection values (for each, P<0.001). Intraocular pressure elevation exceeding 21 mmHg was observed in 26.3% of eyes at 1-month, 15.7% at 3-month, and 5.2% at the last visit, but was controlled with topical anti-glaucomatous medications in all eyes.

CONCLUSION

Intravitreal triamcinolone acetonide application is a promising approach in the treatment of persistent macular oedema due to branch retinal vein occlusion non-respondent to laser photocoagulation.

Delayed absorption of macular edema accompanying serous retinal detachment after grid laser treatment in patients with branch retinal vein occlusion☆

PURPOSE

To study the detailed process of macular edema (ME) absorption after grid laser photocoagulation in patients with branch retinal vein occlusion (BRVO). The influence of pretreatment serous retinal detachment (SRD) at the fovea on patient outcome was also evaluated.

DESIGN

Retrospective, interventional, comparative case series.

PARTICIPANTS

Thirty-seven BRVO patients presenting with severe ME.

METHODS

Patients were treated with grid laser photocoagulation with 6 months of follow-up examinations. Baseline and post-treatment examinations included measurements of visual acuity (VA), fluorescein angiography, and detailed imaging of ME by optical coherence tomography (OCT). Macular thickness was defined as the distance from the inner retinal surface to the outer border of the sensory retina (foveal retinal thickness) and also to the inner border of the retinal pigment epithelium including the SRD (total foveal elevation).

MAIN OUTCOME MEASURES

Post-treatment macular thickness with OCT, VA converted to the logarithm of the minimum angle of resolution, and absorption of SRD, and correlations of macular thickness and VA both before and after treatment.

RESULTS

Total foveal elevation and VA were significantly improved at 1, 3, and 6 months after treatment. There was also a significant correlation between reduction of total foveal elevation and increase in VA. Fourteen eyes (37.8%) displayed SRD, as evidenced by OCT at the baseline. In eyes without SRD, foveal retinal thickness and VA had significantly improved in a time-dependent manner. However, although SRD itself was almost absorbed 6 months after treatment, the improvement of both VA and total foveal elevation in eyes with pretreatment SRD was not significant compared with baseline conditions. Both post-treatment total foveal elevation and VA of eyes with SRD tended to be worse than eyes without SRD.

CONCLUSION

The presence of subfoveal SRD retards the absorption of ME and recovery of VA after grid laser photocoagulation in patients with BRVO.

Internal limiting membrane peeling for decompression of macular edema in retinal vein occlusion: a report of 14 cases

BACKGROUND

Currently, there is no proven treatment for macular edema due to central retinal vein occlusion (CRVO). Moreover, not all cases with macular edema due to branch retinal vein occlusion (BRVO) respond to laser photocoagulation. We postulated that internal limiting membrane (ILM) peeling for decompression of macular edema in cases of retinal vein occlusion would facilitate egress of blood and extracellular fluid out of the inner retinal layers, leading to reduction of macular edema and improvement in visual acuity.

METHODS

Fourteen consecutive patients with macular edema due to CRVO or selected cases of BRVO, not eligible for laser photocoagulation, underwent pars plana vitrectomy with removal of preretinal hyaloid and peeling of the ILM stained with indocyanine green dye.

RESULTS

In all cases, intraretinal blood and retinal thickening diminished within 6 weeks of surgery. Visual acuity improved in 78.6% of cases. No surgical complications occurred, although one patient developed nuclear cataract 10 months postoperatively.

CONCLUSION

Pars plana vitrectomy with ILM peeling in selected cases of CRVO and BRVO showed improvement in visual acuity in this nonrandomized, noncontrolled study. This pilot study adds support to the concept that ILM peeling may of visual benefit when compared with the natural history in these vaso-occlusive diseases.

Eccentricity and measurement variability and repeatability with the retinal thickness analyser

AIMS

To define the variability and repeatability of retinal thickness measurements using the retinal thickness analyser (RTA) and to elucidate any interaction between eccentricity (that is, position relative to the fovea) and variability and repeatability.

METHODS

The sample comprised 20 normal subjects of mean age 33 years. Each subject attended for two visits. Repeated RTA scans were acquired centred on the fovea and for any one of the four possible non-foveal scan areas. The mean retinal thickness (+SD) was calculated for a series of concentric circular bands centred on fixation. A repeated measures analysis of variance (ANOVA) was used to determine any significant interaction between the variability of RTA thickness values and eccentricity.

RESULTS

The group mean coefficient of variation and coefficient of repeatability were highest at the fovea. The repeated measures ANOVA revealed that the within test variability of RTA measurements varied significantly with eccentricity (p<0.0001). Similarly, the between test repeatability varied significantly with eccentricity (p = 0.045).

CONCLUSION

The significantly elevated within test variability and between test repeatability in the foveal area need to be considered when using the RTA to evaluate patients with macular disease.

Comparison between retinal thickness analyzer and optical coherence tomography for assessment of foveal thickness in eyes with macular disease

PURPOSE

To use the retinal thickness analyzer (RTA) and optical coherence tomography (OCT) scanners for quantitative measurement of retinal thickness in eyes with macular disease.

DESIGN

In a cross-sectional study, 44 patients (55 eyes) with macular disease and sufficient media clarity to visualize the fundus using clinical biomicroscopy underwent an ophthalmologic examination, fluorescein angiography, RTA, and OCT during the same visit.

METHODS

Foveal and foveal center (foveolar) retinal thickness measurements were obtained by RTA and by OCT.

RESULTS

Retinal thickness measurements were obtained by OCT in all 55 eyes and by RTA in 34 eyes (62%, primarily due to interference from media opacities). In the 34 eyes in which measurements were obtained by both instruments, mean foveal thickness was 291 and 269 microm for OCT and RTA, respectively; foveolar thickness was 277 and 265 microm, respectively. OCT and RTA measurements of foveal thickness were strongly correlated (intraclass correlation coefficient = 0.89), as were measurements of the foveolar thickness (intraclass correlation coefficient = 0.94). Topographic maps generated by the two techniques yielded qualitatively similar information.

CONCLUSIONS

Overall, there was excellent agreement between RTA and OCT measurements. Each technique has advantages that may make its use preferable in a particular subgroup of eyes or to describe a particular disease process. An important consideration is that media opacities create less interference for OCT than for RTA, so that in study populations with a moderate-to-high prevalence of media opacity, images can be obtained in a greater percentage of eyes by OCT than by RTA.

Pars plana vitrectomy for cystoid macular edema secondary to sarcoid uveitis

OBJECTIVE

To examine the results of pars plana vitrectomy for cystoid macular edema secondary to sarcoid uveitis resistant to medical treatment.

DESIGN

Retrospective, interventional, noncomparative case series.

SUBJECTS

Fourteen consecutive subjects (18 eyes) with cystoid macular edema associated with sarcoid uveitis resistant to medical treatment.

INTERVENTION

All eyes underwent pars plana vitrectomy. Nine eyes also underwent peeling of the epiretinal membrane or removal of the posterior vitreous cortex.

MAIN OUTCOME MEASURES

Status of macular edema, visual acuity, and complications.

RESULTS

Ten eyes (56%) improved 2 or more lines of Snellen visual acuity within 12 months. Six eyes (33%) remained unchanged, within a line of preoperative Snellen visual acuity, and two eyes (11%) worsened by 2 or more lines of Snellen visual acuity. Slit-lamp biomicroscopy showed that cystoid macular edema had resolved in 14 eyes (78%) within 9 months postoperatively. One eye (6%) had minimal edema, whereas three eyes (17%) remained unchanged biomicroscopically at the final visit. Postoperative complications included cataract formation, glaucoma, optic nerve atrophy, epiretinal membrane formation, and tractional retinal detachment. No severe postoperative inflammation was noted.

CONCLUSIONS

Pars plana vitrectomy seems to have a beneficial effect on cystoid macular edema caused by sarcoidosis resistant to medical treatment.

A quantitative in vivo study of retinal thickness before and after laser treatment for macular edema due to retinal vein occlusion

PURPOSE

To evaluate quantitatively the effect of grid laser photocoagulation in macular edema due to central and branch retinal vein occlusion, using the retinal thickness analyzer.

METHODS

Five patients with cystoid and non-cystoid macular edema were studied before and after argon grid laser treatment. All were examined clinically, with fluorescein angiography, and measurement of retinal thickness. Macular thickness was correlated to visual acuity measured on the ETDRS chart.

RESULTS

Laser-slit images obtained with the retinal thickness analyzer in patients with macular edema disclosed discrete intraretinal changes after photocoagulation. Biomicroscopy and fluorescein angiography were insensitive to these small changes in the retinal thickness. No patient had any change in visual acuity after three months, but the retinal thickness was greater at this interval. The retinal thickening may be explained by a postoperative inflammatory response or by altered retinal blood flow or, in two of the eyes, by the effect of combined peripheral photocoagulation.

CONCLUSIONS

The retinal thickness analyzer offers a refined tool for the diagnosis of subclinical changes of macular edema in retinal vein occlusion and is therefore also useful for assessing the effects of treatment.

Perimetric sensitivity and retinal thickness in eyes with macular edema resulting from branch retinal vein occlusion

PURPOSE

To document and study the relationship between perimetric sensitivity and retinal thickness at the foveal and parafoveal points in eyes with macular edema associated with branch retinal vein occlusion.

METHODS

A prospective study was performed using the central 10-2 Humphrey perimetry program and optical coherence tomography. Seventeen eyes with branch retinal vein occlusion were eligible showing macular edema without macular nonperfusion or massive retinal hemorrhage.

RESULTS

The sensitivity and retinal thickness were significantly correlated at the fovea (r = -0.629, P =.006) as well as 1 (r = -0.656, P <.0001) and 3 (r = -0.885, P <.0001) degrees apart from the fovea. The visual acuity that is expressed as a logarithm of the minimum angle of resolution (LogMAR) also correlated with retinal thickness (r = 0.591, P =.011).

CONCLUSION

The increased retinal thickness resulting from macular edema is closely correlated with retinal sensitivity as measured by automated static perimetry both at the fovea and parafovea. Measuring the retinal thickness using optical coherence tomography may be useful in monitoring macular edema in eyes with branch retinal vein occlusion.