جستجوی مقالات مرتبط با کلیدواژه "photocoagulation" در نشریات گروه "پزشکی"

Panretinal photocoagulation (PRP) impacts macular function in eyes with early proliferative diabetic retinopathy (PDR). Herein, we used the multifocal electroretinogram (mfERG) to objectively investigate this concept.

In this prospective interventional case series, we enrolled patients with treatment-naive early PDR, absence of clinically significant macular edema, and requirement for PRP. All participants underwent detailed ocular examinations. We measured the best-corrected distance visual acuity (BCDVA), conducted optical coherence tomography imaging to measure central macular thickness (CMT), and performed mfERG at baseline and 3 months post-PRP. Amplitude and latency of the mfERG response were evaluated within the innermost four of the five concentric rings.

We enrolled 29 eyes of 23 patients with a mean (standard deviation) age of 54.3 (8.8) years and male-to-female ratio of 1:1.3. The mean BCDVA was unchanged post-treatment (P >0.05), and the BCDVA in 26 eyes (89.7%) was either improved or unchanged, whereas in three eyes (10.3%) it decreased. The mean CMT was unchanged post-PRP (P >0.05). Concerning the mfERG, the mean P1 amplitudes decreased significantly in all four concentric rings from the foveola at 3 months post-PRP compared with baseline values (all P <0.05); however, the latencies were unchanged (all P >0.05). At baseline, BCDVA correlated significantly with both the amplitude (r = + 0.55; P <0.05) and latency (r = - 0.38; P <0.05) of the mfERG in the central ring, whereas a significant correlation was detected with only the amplitude at 3 months post-PRP (r = + 0.52; P <0.05).

Macular function was decreased 3 months post-PRP in patients with early PDR, as indicated by decreased amplitude of the mfERG, whereas the functional and anatomical parameters were stable. The mfERG served as an objective tool for measuring retinal function and predicting visual outcomes post-PRP in eyes with early PDR. A higher amplitude in the mfERG correlated substantially with a better visual outcome post-PRP. Further multi-center longitudinal studies with robust designs including different PDR severity levels may reveal additional objective aftereffects of PRP.

To report two cases of diffuse unilateral subacute neuroretinitis (DUSN) from northern Iran and to present the sequential imaging.

Two patients with large subretinal nematodes were evaluated and managed in our clinic. Serial fundus photography and optical coherence tomography (OCT) imaging were used to document the course of the disease. Laser photocoagulation was administered to manage the patients.

The migration of the nematodes from subinternal limiting membrane space to subretinal space was documented in one case, coinciding with the onset of inflammatory and destructive processes. Both patients were successfully managed using laser photocoagulation alone. Follow-up examinations revealed partial recovery of the outer retinal layers and improvement in visual acuity. Nevertheless, some persistent atrophy in the retinal nerve fiber layer and ellipsoid layer was noted in the final examination.

We presented two cases of DUSN from northern Iran, with OCT documentation of transretinal migration in one case. Photocoagulation laser alone is an effective treatment modality in the early stage. The suboptimal final visual acuity appears to be linked to both inner and outer retinal layers’ damage.

Proliferative diabetic retinopathy (PDR) is a serious sight-threatening disease, and half of the patients with high-risk PDR can develop legal blindness within 5 years, if left untreated. This study was aimed at comparing panretinal photocoagulation (PRP) and intravitreal ranibizumab injections in terms of radial peripapillary capillary (RPC) density on optical coherence tomography angiography (OCTA) in patients with treatment-naive PDR .

This open-label, prospective, randomized clinical trial included 50 patients with treatment-naive PDR with optic disc neovascularization and randomized them into two groups: group 1, with patients undergoing two sessions of PRP 2 weeks apart, and group 2, with patients received three intravitreal ranibizumab injections (0.5 mg) 1 month apart for 3 consecutive months. Patients underwent a full ophthalmological examination, including best-corrected distance visual acuity (BCDVA) measurement in the logarithm of minimal angle of resolution (logMAR) notation and OCTA before intervention and monthly after the last laser session or the first intravitreal ranibizumab injection for 3 months of follow-up. Visual field (VF) was tested at the beginning and end of 3 months.

Forty-two (84%) eyes completed the 3-month follow-up, including 22 eyes in the PRP group (88%) and 20 (80%) eyes in the ranibizumab group. The two groups were comparable in terms of demographic characteristics, diabetes duration, baseline BCDVA, glycated hemoglobin level, OCTA parameters, VF indices, and intraocular pressure (all P > 0.05). The RPC density change from baseline to the 3-month follow-up was significantly lower in the PRP group than in the ranibizumab group (mean difference in RPC density change: - 3.61%; 95% confidence interval: - 5.57% to - 1.60%; P = 0.001). The median (interquartile range) logMAR change from baseline to the 3-month follow-up (0.0 [0.2]) was significantly higher in the PRP group than in the ranibizumab group (- 0.15 [0.3]; P < 0.05). The median changes in central foveal thickness from baseline to the 3-month follow-up differed significantly between the two groups (P = 0.001).

In eyes with PDR and neovascularization of the disc RPC density on OCTA increased in the ranibizumab group and decreased in the PRP group. Visual acuity gain was higher in the ranibizumab group than in the PRP group. Future multicenter trials addressing our limitations are required to verify the findings of this study.