Sickle cell retinopathy in young children in Jamaica

Ophthalmological examinations were performed on 59 of the 74 (80 percent) children with homozygous sickle cell (SS) disease and on 37 of the 54 (69 percent) children with sickle cell-haemoglobin C(SC) disease, aged 5-7.5 years, within the cohort study of sickle cell disease. Arteriolar sheathing was the commonest retinal vessel abnormality, occurring in 30/59 (51 percent) SS children and in 11/37 (30 percent) SC children. Peripheral arteriolar closure was observed in 14 (24 percent) SS children and in 6 (16 percent) SC children. Arteriovenous anastomoses were seen in 3 children, but proliferative retinopathy was not identified. Capillary changes often occurred in patients without confluent closure, suggesting that complex remodelling of the capillary bed may precede retinal nonperfusion. Discrete retinal patches similar to schisis cavities resulting from intraretinal haemorrhages were found in 22 (37 percent) SS children and in 9 (24 percent) SC children, but haemorrhages were observed in only 2 patients (1 SS, 1SC). Vitreous opacities were common and were generally associated with retinal vessel disease. Retinal changes were consistently more common in children with SS disease, though the differences failed to reach statistical significance. The prevalence of peripheral vascular closure and retinal patches showed a significant upward trend with age. These observations contrast with the greater prevalence of proliferative retinopathy characterising SC disease in adults.(AU)

Salmon-patch hemorrhages after central retinal artery occlusion in sickle cell disease

In two patients with sickle cell disease (one hemoglobin SC and one hemoglobin SS), central retinal artery occlusion developed. In one case, the occlusion followed a retrobular injection of lidocaine hydrochloride. Although the central retinal artery reperfused in each patient, many secondary peripheral retinal ateriolar occlusions remained. During the subsequent days, multiple salmon-patch hemorrhages developed in the distribution of these occluded arterioles. In one patient, the salmon-patch hemorrhages evolved into atrophic schisis cavities. These unusual cases allowed us to document the origin of salmon-patch hemorrhages after peripheral retinal arteriolar occlusions. The development of the hemorrhages was a delayed phenomenon that occurred hours to days after the initial vascular occlusion. Reperfusion of the damaged ischemic vessels with a blowout of the walls of the vessels seems the most likely explanation for this phenomenon. (Au)

Photocoagulation and diathermy in the treatment of proliferative sickle retinopathy

The O'Malley Log II portable photocoagulator was used to treat the worse eye of 36 patients with proliferative sickle cell retinopathy flat on the retinal surface. The technique involved direct coagulation of the feeder arterioles before treatment of the new vessels themselves. The photocoagulator was most successful in treating the lesions and 131 of 137 retinitis proliferans (RP) lesions were occluded. In only one RP lesion did the photocoagulator have insufficient power to occlude the lesion. Vitreous haemorrhage occurred in only one patient and small round localized retinal haemorrhages in five. The Manchester portable diathermy machine successfully occluded all 29 raised RP lesions and fifty feeder arterioles in thirteen patients. Anterior segment ischaemia occurred in only one patient who had advanced traction retinopathy involving 360 degrees of arc of the retinal circumference before treatment. No recurrence of retinopathy over a 2-year follow-up period was seen in seven patients and in the remainder there was no recurrence in the 2 months after treatment. (Summary)

Ocular findings in homozygous sickle cell anemia in Jamaica

Retinal detachment, brown mottled areas and microcapillary abnormalities at the posterior pole are previous undescribed retinal features of sickle cell anemia that were found in a series of 76 Jamaicans with homozygous sickle cell anemia. These subjects were consecutive patients in a sickle cell clinic during a one-month period; thus, the series is unique in that bias in selective inclusion of cases with ocular pathology was avoided. Tortuosity of the major retinal vessels, previously reported as a major feature of the retinopathy was found in unaffected relatives of SS patients in the same family with normal hemoglobin genotype. Angioid streaks were not seen in this series. (AU)