The Role of Laser Photocoagulation in Treating Diabetic Macular Edema in the Era of Intravitreal Drug Administration: A Descriptive Review.

Background and Objectives: This study aimed to elucidate the role of laser photocoagulation therapy in the treatment of diabetic macular edema (DME) as an alternative to, or in conjunction with, the first-line treatment, anti-vascular endothelial growth factor (VEGF). Materials and Methods: A comprehensive literature search to identify studies that evaluated the efficacy of laser photocoagulation therapy in the management of DME was performed. The relevant findings of the efficacy of focal/grid laser therapy from data in randomized, controlled trials were synthesized, and the potential of new laser technologies, such as navigated laser systems, pattern scan lasers, and subthreshold lasers, was explored. The usefulness of multimodal imaging-guided laser therapy was also evaluated, with a focus on the potential contribution to anti-VEGF therapy. Results: Focal laser photocoagulation targeting microaneurysms remains an effective therapeutic approach to chronic refractory edema, despite the widespread use of anti-VEGF therapy. To achieve the best possible treatment outcomes, precise identification of microaneurysms is essential. This requires the use of multimodal imaging-guided, highly accurate, minimally invasive coagulation techniques. Subthreshold laser therapy can also reduce the frequency of anti-VEGF injections and minimize treatment burden. Conclusions: Further studies are needed to determine the optimal timing and settings for laser photocoagulation therapy and the potential of new laser technologies in the management of DME. Nevertheless, laser photocoagulation therapy plays an important role in the management of DME, in conjunction with anti-VEGF therapy.

Navigated direct photocoagulation with a 30-ms short-pulse laser for treating microaneurysms in diabetic macular edema exhibits a high closure rate.

This study carried out direct photocoagulation for treating microaneurysms (MAs) in diabetic macular edema (DME) using a navigation laser system with a 30-ms pulse duration. The MA closure rate after 3 months was investigated using pre and postoperative fluorescein angiography images. MAs primarily inside the edematous area based on optical coherence tomography (OCT) maps were selected for treatment, and leaking MAs (n = 1151) were analyzed in 11 eyes (eight patients). The total MA closure rate was 90.1% (1034/1151), and the mean MA closure rate in each eye was 86.5 ± 8.4%. Mean central retinal thickness (CRT) decreased from 471.9 ± 73.0 µm to 420.0 ± 87.5 µm (P = 0.049), and there was a correlation between the MA closure rate and the CRT reduction rate (r = 0.63, P = 0.037). There was no difference in the MA closure rate depending on the degree of edema thickness based on a false-color topographic OCT map image. Direct photocoagulation for DME with a short pulse using the navigated photocoagulator resulted in a high MA closure rate in just 3 months and a corresponding improvement in retinal thickness. These findings encourage the use of a new therapeutic approach for DME.

Seven Microaneurysms: Description of an Experimental Rodent Model for Neurovascular Training.

AIM: To demonstrate the microsurgical procedures, and to evaluate the feasibility of living models of experimental neurovascular training by developing new complex vascular exercises mimicking the most common intracranial aneurysms. MATERIAL AND METHODS: The procedures were performed under a Zeiss (OPMI pico f170) microscope using basic microsurgery instruments, 10/0 Nylon and blue Polypropylene micro-sutures. We selected adult albino Wistar rats weighing between 258 and 471g each. Seven different aneurysm types were created using carotid, jugular, cava, aorta and femoral vessels. RESULTS: Seven types of aneurysm were designed and created in the rat with a high-medium successful rate. There are differences in terms of realism and the difficulty of performance, according to the different types: lateral wall, bifurcation, top of the basilar, fusiform, fusiform + involved branch, Anterior Communicating Artery (ACoA) and giant. The steps and technical issues to produce these exercises are described. CONCLUSION: We show the feasibility of creating several types of aneurysm using different vessels in a rodent model. Training on these models help to improve microsurgical skills, allowing safe practice for neurosurgeons in all stages of their career.

Visualization of microaneurysms in macular telangiectasia type 1 on optical coherence tomography angiography before and after photocoagulation.

PURPOSE: To evaluate changes in the visualization of microaneurysms (MAs) in cases of macular telangiectasia (Mac Tel) type 1 on optical coherence tomography angiography (OCTA) before and after treatment with direct photocoagulation and to evaluate their relationship with treatment efficacy. METHODS: The study included 12 eyes from 12 patients (8 men, 4 women; mean age 72.1 years) with Mac Tel type 1 accompanied by cystoid macular edema. OCTA for the evaluation of MAs was performed before and 15 min and 6, 12, and 24 weeks after photocoagulation. The best-corrected visual acuity (BCVA) and central retinal thickness (CRT) were also evaluated. RESULTS: A total of 73 MAs were detected within the areas of macular edema on OCTA, and 39 of these underwent photocoagulation. At 15 min after treatment, 17 MAs were no longer visible on OCTA. At 6 weeks, two MAs had reappeared, whereas five additional MAs were no longer visible. The CRT in eyes with resolved MA was significantly less than that in eyes with persistent MAs (p = 0.016). At 24 weeks, seven eyes had no visible MAs, and the BCVA was not significantly different from baseline. CONCLUSION: OCTA can monitor changes in the visualization of MAs associated with Mac Tel type 1 after direct photocoagulation. Eyes in which MAs disappeared after treatment could recover from cystoid macular edema.

Incidental Microaneurysms During Microvascular Surgery: Incidence, Treatment, and Significance.

BACKGROUND: Although new imaging tools have been developed for the detection of smaller aneurysms, angiographically negative microaneurysms are still encountered during cerebral microsurgery. Currently, only limited information regarding incidence and efficacy of treatment of these microaneurysms is available. METHODS: We investigated the incidence and treatment of incidental microaneurysms (IMAs) in the last 5 years. IMAs are unidentifiable and invisible on preoperative angiography, but are detected during microvascular surgery. The inclusion criteria were aneurysm cases treated with microsurgery via transsylvian approaches, and those undergoing preoperative digital subtraction angiography. RESULTS: This study enrolled 484 surgical cases (248 cases of subarachnoid hemorrhage and 236 cases of unruptured aneurysms) in 460 patients, and 33 tiny aneurysms were found in 31 operative cases (6.4% incidence per operation). The most typical type was located on another branching site of the middle cerebral artery found during neck clipping of the middle cerebral artery bifurcation aneurysm. A patient with multiple aneurysms presented a statistically significant risk (375/78 vs. 15/16; P < 0.001) of IMA identification. IMAs were treated by clipping and wrapping in 18 and 15 cases, respectively, without complications. CONCLUSIONS: This study revealed a 6.4% incidence of IMAs; however, this could be underestimated because of the limited range of inspection. Early detection of an IMA through careful inspection during microvascular surgery could be beneficial, especially in patients with multiple aneurysms.

Treatment of macular hemorrhage in retinal arterial microaneurysm: anatomic site-oriented therapy.

PURPOSE: To investigate the usefulness of anatomic site-oriented therapy for macular hemorrhage secondary to retinal arterial macroaneurysm (RAM). STUDY DESIGN: Retrospective observational study, clinical case series METHODS: Twenty-seven consecutive patients (27 eyes) with macular hemorrhage secondary to RAM were classified according to the retinal layer(s) with hemorrhage identified by optical coherence tomography into 4 types and treated differentially. Vitrectomy was conducted for subinternal limiting membrane hemorrhage (SILMH), intravitreal gas injection for subretinal hemorrhage (SRH) or intraretinal hemorrhage (IRH), and vitrectomy and intravitreal air/gas exchange for multilevel hemorrhage (at least 2 among SILMH/SRH/IRH). RESULTS: Complete displacement or resolution of the macular hemorrhage was achieved in all 27 eyes: 7 with SILMH, 7 with SRH, 3 with IRH, and 10 with multilevel hemorrhage. Compared with the baseline score, the 3-month postoperative Early Treatment Diabetic Retinopathy Study score (mean ± SD) improved significantly in SILMH (+42.9 ± 6.9 letters; P < .0001, paired t test), multilevel hemorrhage (+23.9 ± 14.4 letters; P = .0005), and SRH (+17.7 ± 18.4 letters; P = .0440), but not in IRH (+6.7 ± 9.0 letters; P = .3228). Compared with the baseline thickness, the 3-month postoperative central retinal thickness decreased significantly in multilevel hemorrhage (-930.3 ± 290.8 µm; P < .0001), SILMH (-628.4 ± 177.0 µm; P < .0001), IRH (-508.3 ± 72.1 µm; P = .0066), and SRH (-476.9 ± 300.0 µm; P = .0056). The central ellipsoid zone was detectable in 7/7 eyes with SILMH but in none of the eyes in the other 3 groups (P < .0001). No retinal detachment or macular hole occurred in any eyes. CONCLUSION: For macular hemorrhage secondary to RAM, anatomic site-oriented therapy using different treatments targeting the hemorrhagic retinal layers is useful. The optimal treatments for individual hemorrhagic retinal layers require further studies.

Peripheral Microvascular Abnormalities Detected by Wide-Field Fluorescein Angiography in Eyes with Branch Retinal Vein Occlusion.

PURPOSE: To evaluate the location of microvascular abnormalities using wide-field fluorescein angiography (WFFA) and investigate the impact on visual outcome in eyes with branch retinal vein occlusion (BRVO). METHODS: Forty eyes of 39 patients (24 males and 15 females with an average age of 71 years) were retrospectively reviewed. One patient had BRVO bilaterally. WFFA was performed in all patients to evaluate perfusion status and detect microvascular abnormalities. The WFFA images were divided into 3 zones: zone 1, posterior pole; zone 2, mid-periphery; zone 3, far periphery, in order to document the presence of microvascular abnormalities. Scatter retinal photocoagulation (PC) was performed for retinal neovascularization (NV) and/or widespread nonperfused areas (NPAs). RESULTS: The incidence of microvascular abnormalities in zone 3 was significantly (p < 0.0001) less than in zones 1 and 2. The presence of larger NPAs in zone 1, but not in zone 3, was associated with the incidence of NV and vitreous hemorrhage. The presence of peripheral lesions and the application of PC did not affect the visual outcome. CONCLUSION: The presence of peripheral abnormalities or scatter PC for NPAs did not affect the visual outcome in eyes with BRVO.