ORIGINAL ARTICLES
Tomographic assessment of vitreous surgery for diabetic macular edema☆

https://doi.org/10.1016/S0002-9394(99)00409-2Get rights and content

Abstract

PURPOSE:

To evaluate the retinal structure before and after vitrectomy for diabetic macular edema and to assess the correlation between thickness of neurosensory retina and best-corrected visual acuity.

METHODS:

Tomographic features of 13 eyes (nine patients) with diabetic macular edema were prospectively evaluated with optical coherence tomography before and after vitrectomy. The foveal thickness (the distance between the inner retinal surface and the retinal pigment epithelium) and the retinal thickness (thickness of neurosensory retina) were measured by optical coherence tomography preoperatively and postoperatively. The correlation of the best-corrected visual acuity with foveal and retinal thickness was determined.

RESULTS:

All 13 eyes had retinal swelling with low intraretinal reflectivity. In addition to retinal swelling, there were cystoid spaces in five (38%) of 13 eyes, a serous retinal detachment in three (23%), and both cystoid spaces and serous detachment in three (23%). Six months postoperatively, the mean foveal thickness significantly decreased from 630 ± 170 to 350 ± 120 μm (P < .01, paired t test) and the mean thickness of neurosensory retina decreased from 540 ± 160 to 320 ± 140 μm (P < .01, paired t test). A serous retinal detachment occurred transiently in 3 eyes. Compared with the preoperative level, the postoperative best-corrected visual acuity level improved by more than 2 lines in five of the 13 eyes (38%), remained the same in seven eyes (54%), and decreased in one eye (8%). The postoperative thickness of neurosensory retina at the fovea and best-corrected visual acuity level at the sixth postoperative month had a strong negative correlation (correlation coefficient, −0.76; P < .01, Spearmans rank test).

CONCLUSIONS:

Vitrectomy was generally effective in treatment of diabetic macular edema. Optical coherence tomography demonstrated the intraretinal changes of macular edema and the process of edema absorption. During the process of macular edema absorption, intraretinal fluid appeared to move into the subretinal space in some cases. Best-corrected visual acuity improvement was greater in eyes with less preoperative increase in thickness of neurosensory retina.

Section snippets

Patients and methods

Nine patients with diabetes (seven men and two women; 13 eyes) ages 46 to 68 years (average, 58 years) made up the study population. The inclusion criteria for this study were as follows: clinically detectable diffuse or cystoid macular edema for more than 3 months; best-corrected visual acuity worse than 20/40 before vitrectomy; follow-up period of more than 6 months after surgery; no dense media opacity before and after surgery, such as cataract, vitreous hemorrhage, and so on; neither

Results

Ophthalmoscopically, diffuse macular edema was observed in all 13 eyes, moreover cystoid macular edema in eight eyes Figure 1, Figure 2, Figure 3. No serous retinal detachment could be detected Figure 1, Figure 2, Figure 3. Optical coherence tomography showed retinal swelling in all 13 eyes. An area of low reflectivity was mainly located in the outer retina. In addition to retinal swelling, there were cystoid spaces in five (38%) of 13 eyes, a serous retinal detachment in three eyes (23%), and

Discussion

Optical coherence tomography revealed cross-sectional images of macular edema and the pattern of its absorption. All 13 study eyes had retinal thickening and decreased intraretinal reflectivity. An area of low reflectivity was mainly located in the outer retina. The outer plexiform layer is known to be the preferential site for retinal edema.7 Low reflectivity of the outer retina seems to reflect the swelling of this layer.8, 9 In addition to retinal swelling, cystoid cavities, which were

Cited by (128)

  • Diabetic Macular Edema With and Without Subfoveal Neuroretinal Detachment: Two Different Morphologic and Functional Entities

    2017, American Journal of Ophthalmology

  • Exudative retinal detachment

    2017, Survey of Ophthalmology
    Citation Excerpt :

    Serous macular detachment has been reported on OCT in 15%–30% of patients with DME.28,317 It has been postulated that serous macular detachment occurs due to transient migration of fluid from the cystoid spaces in the retina to the subretinal space.14,218,312 Another theory is that it occurs subsequent to failure of the RPE pump mechanism.157

  • Surgical Management for Diabetic Macular Edema

    2023, Diabetic Macular Edema

  • Optical Coherence Tomography Classification Systems for Diabetic Macular Edema and Their Associations with Visual Outcome and Treatment Responses-An Updated Review

    2022, Asia-Pacific Journal of Ophthalmology

  • Surgical Management of Diabetic Macular Edema

    2021, Cutting-edge Vitreoretinal Surgery

  • Efficacy of Intravitreal dexamethasone implant in different patterns of diabetic macular edema

    2020, Journal of Ophthalmic and Vision Research
View all citing articles on Scopus
☆

This study was supported by grants from the Ministry of Education, Science and Culture of Japan, Tokyo, Japan.

View full text
Copyright © 2000 Elsevier Science Inc. All rights reserved.