A randomized clinical trial evaluating choroidal blood flow and morphology after conventional and pattern scan laser panretinal photocoagulation

Abstract

We prospectively investigated the changes in choroidal blood flow and morphology after panretinal photocoagulation (PRP) in 39 eyes with severe nonproliferative diabetic retinopathy (S-NPDR). Seventeen eyes underwent PRP by conventional laser and 22 eyes underwent pattern scan laser (PASCAL). The choroidal blood flow was assessed by laser speckle flowgraphy, and the subfoveal choroidal thickness (SFCT) was measured with optical coherence tomography before and 1, 4, 8, and 12 weeks after the two types of PRP treatments. The choroidal mean blur rate (MBR) at the macular region was significantly reduced to 86.4% of the baseline level in the conventional laser group and 85.7% in the PASCAL group at Week 12 (P = 0.001, P < 0.001, respectively). The SFCT was significantly increased at 1 week following PRP but it was significantly reduced at Week 8 (P = 0.001, P < 0.001, respectively) in both groups. The differences in the ratio of the MBR and the SFCT was not significant between the conventional laser and PASCAL groups at any time after PRP. The results suggest that appropriate PRP treatments even by the PASCAL method will reduce the choroidal blood flow and the choroidal morphological components.

Retinal Microvascular Resistance Estimated from Waveform Analysis Is Significantly Higher With a Threshold Value in Central Retinal Vein Occlusion

“…[6][7][8][9][10][11] LSFG is a recently developed technique that has been used for visualizing blood flow distributions in the ocular fundus. This method is convenient for measuring blood flows and can be useful for clinical applications (e.g., diabetic retinopathy, [12][13][14][15][16][17][18] glaucoma, 8,19-25 uveitis [26][27][28]. We have previously reported LSFG findings in eyes with CRVO.…”

Clinical and functional state of the retina after inadequate laser coagulation of peripheral vitreochorioretinal dystrophies. Part 2. A study of microcirculation of the macular area

“…Однако вопрос об изменениях микроциркуляторного русла в макулярной зоне у больных с миопией и ПВХРД остается малоизученным. В единичных работах с применением ОКТ-А установлено, что в глазах с миопией уменьшается плотность капилляров сетчатки, а дефицит кровотока в хориокапиллярах увеличивается [10][11][12][13]. Так, у больных с миопией высокой степени (от -6,0 до -16,0 дптр; в среднем -8,2 дптр), передне-задней осью глаза от 26,5 мм и более и при отсутствии дистрофических изменений на периферии и в центре сетчатки по сравнению с пациентами без миопии выявлялось статистически значимое уменьшение толщины субфовеолярной хориоидеи и плотности капилляров [10].…”

Assessment of Choroidal Neovascularization Perfusion: A Pilot Study With Laser Speckle Flowgraphy

“… 29 Subsequently, 830-nm LSFG was used to quantify macular choroidal perfusion in clinical studies of retinal disorders, such as PCV, acute central serous chorioretinopathy, retinitis pigmentosa, and diabetic retinopathy. 18 , 30 – 32 For the purpose of this study, we used a similar approach focusing on the macular area occupied by the CNV: the mean decrease in blood flow was 26% after 1 week. We recorded a pretty high variability of the response, which was, however, strongly correlated with CMT after one week.…”