Fundus fluorescein angiography evaluation of these 43 subjects with diabetic revealed a unilateral CRA in 40 subjects and bilateral in 3 subjects. Of these 43 eyes of subjects with diabetic, 5 (11.36%) had mild NPDR, 20 (45.45%) had moderate NPDR, 12 (29.54%) had severe NPDR, and 6 (13.63%) were diagnosed to have PDR. These patients were further classified as having center-involving DME (37.20%), non center-involving DME (37.20%), and no presence of DME (25.58%) (p = 0.83).
(Table 1) shows the patients characteristics according to the status of macular edema in the study group. Among men, the distribution values of center-involving DME, non center-involving DME, and no DME are 68.75%, 75%, and 27.27% (p = 0.05). Likewise, among women the distribution values of center-involving DME, non center-involving DME, and no DME are 31.25%, 25%, and 72.72% (p = 0.03). No statistical significant difference was observed for age, duration of diabetes, and stages of diabetic retinopathy among the groups.
Table 1
Patients characteristics according to the status of macular edema in the study group
DEMOGRAPHIC AND CLINICAL FINDINGS | Center involving DME* N = 16 | Non center involving DME* N = 16 | No DME* N = 11 | P Value |
Age (Mean in years ± SD) | 59.93 ± 8.04 | 54.18 ± 7.44 | 60.08 ± 7.22 | 0.34 |
Duration of diabetes (Mean in years ± SD) | 13.75 ± 8.32 | 11.37 ± 6.11 | 9.22 ± 1.85 | 0.1 |
Gender N (%) | | | | |
Male | 11 (68.75%) | 12 (75%) | 3 (27.27%) | 0.05 |
Female | 5 (31.25%) | 4 (25%) | 8 (72.72%) | 0.03 |
DR stage N (%) | | | | |
Mild NPDR† | 2 (12.5%) | 1 (6.25%) | 2 (18.18%) | 0.83 |
Moderate NPDR† | 7 (43.75%) | 10 (62.5%) | 3 (27.27%) |
Severe NPDR† | 4 (25%) | 4 (25%) | 4 (36.36%) |
PDR‡ | 3 (18.75%) | 1 (6.25%) | 2 (18.18%) |
*DME- Diabetic macular edema,† NPDR – Non proliferative diabetic retinopathy, ‡PDR – Proliferative diabetic retinopathy |
(Table 2) shows relationship of DME with area of supply by CRA. The subjects with center-involving DME had upper, 31.25%; central, 37.5%; and lower, 31.25% area of supply by CRA. The subjects with non center-involving DME had upper, 12.5%; central, 50%; and lower, 37.50% area of supply by CRA. The subjects with no DME had upper, 9.09%; central, 56.54%; and lower, 36.36% area of supply by CRA.
Table 2
Relationship of diabetic macular edema and area of supply by cilioretinal artery
Area of Supply by CRA* | Upper | Central | Lower |
Center involving DME† | 5 (31.25%) | 6 (37.5%) | 5 (31.25%) |
Non center involving DME† | 2 (12.5%) | 8 (50%) | 6 (37.5%) |
No DME† | 1 (9.09%) | 6 (56.54%) | 4 (36.36%) |
P Value | 0.25 | 0.10 | 0.36 |
*CRA – Cilioretinal artery, †DME – Diabetic macular edema |
Table 3 shows the distribution of DME with the presence and absence of CRA. The distribution of center-involving DME in the presence of CRA is 37.2% and in the absence of CRA is 44.2%. The distribution of non center-involving DME in the presence of CRA is 39.5% and in the absence of CRA is 20.9%, and the distribution of no DME in the presence of CRA is 18.6% and in the absence of CRA is 25.5%. The presence of a CRA was observed as an important factor when the overall rates of macular edema in these eyes were compared to those of macular edema in eyes without the presence of CRA (p = 0.062).
Table 3
Distribution of diabetic macular edema with presence and absence of cilioretinal artery
CRA Status* | Centre Involving DME† | Non-Centre involving DME | No DME |
CRA Present | 37.2% | 39.5% | 18.6% |
CRA Absent | 44.2% | 20.9% | 25.5% |
*CRA – Cilioretinal artery, †DME – Diabetic macular edema |
Table 4 shows the relationship between area of supply of CRA and area of retinal thickness. When CRA supplies the central area, the maximum retinal thickness was noted at the temporal quadrant (332.68 ± 89.95) and has non center-involving DME (194.87±121.06 mm), When CRA supplies the lower area, the maximum retinal thickness was noted at the superior quadrant (342.42 ± 88.92) and has center-involving DME (395±285.75 mm) and with CRA supply in the upper area, the maximum retinal thickness was noted at the nasal quadrant (328.44 ± 129.82) with center-involving DME (292±192.79 mm).
Table 4
Relationship between area of supply of cilioretinal artery and area of retinal thickness.
Area of supply of CRA | Superior | Temporal | Inferior | Nasal | At fovea | P value |
Centre | 324.34 ± 58.83 | 332.68 ± 89.95 | 320.84 ± 83.26 | 328.42 ± 77.57 | 306.10 ± 120.33 | 0.9077 |
Upper | 293.5 ± 132.15 | 308.69 ± 160.56 | 325.13 ± 129.40 | 328.44 ± 129.82 | 317.38 ± 152.69 | 0.9818 |
Lower | 342.42 ± 88.92 | 332.04 ± 101.38 | 319.08 ± 112.80 | 336.62 ± 127.90 | 318.69 ± 164.81 | 0.9827 |