To determine the possible adverse effects and safe dose range of intravitreal colistin, an antibiotic, after its intravitreal application.Twenty eyes of 20 adult male and female New Zealand white r...

To investigate the effect of menstrual cycle-related hormonal fluctuations on retinal and choroidal microvasculature using swept-source optical coherence tomography angiography (SS-OCTA). In this prospective study, a cohort of 31 healthy women with regular menstrual cycles was enrolled. SS-OCTA imaging was performed during three standardized menstrual phases: early follicular (day 3), ovulatory (day 14), and mid-luteal (day 21). Macular and peripapillary regions were evaluated using 3 × 3 mm and 4.5 × 4.5 mm scan protocols, respectively. Vessel density (VD) in the superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris (CC) was automatically quantified using the device’s software. Choroidal thickness (CT) was manually measured in all quadrants, and the foveal avascular zone (FAZ) area was manually delineated by two independent graders. To control for diurnal variation, all measurements were conducted between 11:00 a.m. and 12:00 p.m. A statistically significant decrease in macular CT was observed across the menstrual phases (p = 0.002), along with significant variations in peripapillary CT in the temporal and inferior quadrants (p = 0.004 for both). VD in the peripapillary region showed significant differences in the superior quadrant of the SCP (p = 0.040), the inferior quadrant of the DCP (p = 0.008), and in the temporal and inferior quadrants of the CC (p = 0.011 and p = 0.007, respectively). In the macula, CC-VD in the inferior quadrant differed significantly (p = 0.030). FAZ area remained stable throughout the cycle. Post-hoc analysis revealed significant differences between the early follicular, ovulatory, and mid-luteal phases. Hormonal fluctuations throughout the menstrual cycle appear to influence both retinal and choroidal microvasculature, particularly in the choriocapillaris and peripapillary regions. These findings underscore the importance of considering menstrual phase when interpreting OCTA measurements in women of reproductive age, to improve diagnostic accuracy and consistency in clinical and research settings.

Macular Telangiectasia Type 2: Long-Term Disease Progression and Management of Complications - Turkish Journal of Ophthalmology

Purpose: To compare macular microvascular changes after horizontal rectus and inferior oblique (IO) muscle surgeries using swept-source optical coherence tomography angiography (OCTA) and to assess the distinct vascular effects of each surgical approach. Methods: Eighty-two pediatric and adolescent patients with concomitant strabismus underwent unilateral extraocular muscle surgery. Group 1 (n = 43) received horizontal rectus muscle surgery; Group 2 (n = 39) underwent IO weakening surgery. The fellow unoperated eye served as a control. Macular microvasculature was evaluated before surgery, at 1 week, and 1 month postoperatively using a swept-source OCTA system. Vessel density (VD) of the superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris (CC), as well as the foveal avascular zone area (FAZ), was quantitatively analyzed. Results: In the horizontal rectus group, SCP VD significantly increased in the 1st week compared to baseline (49.97% ± 2.41% vs. 51.16% ± 3.23%, p = 0.037) and returned to baseline values in the 1st month. A transient increase in CC VD was also observed at the 1st week (p = 0.006). No significant changes occurred in the DCP and FAZ. In the IO group, no significant changes were found in the SCP, DCP, or FAZ. However, a mild, transient increase in CC VD was observed at the 1st week (p = 0.001), which returned to baseline by the 1st month. Conclusion: Horizontal rectus muscle surgery induces significant but transient changes in macular retinal and choroidal perfusion. In contrast, IO muscle surgery induces only localized and temporary choroidal alterations. OCTA may therefore serve as a valuable noninvasive tool for postoperative monitoring of vascular alterations in strabismus surgery.

To assess the ocular characteristics, retinal microvasculature, and long-term outcomes of patients with nanophthalmos associated with mutations in the membrane frizzled-related protein (MFRP) gene, and to compare these findings with those observed in nanophthalmos cases without MFRP gene mutations. In this retrospective cohort study, patients with MFRP-associated nanophthalmos and those with nanophthalmos without MFRP gene mutations were included. Best-corrected visual acuity (BCVA), spherical equivalent (SE), axial length (AL), optical coherence tomography (OCT), and OCT angiography parameters-including vascular density (VD) and foveal avascular zone (FAZ) measurements in the superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris (CC)-were evaluated at presentation and at the 5th-year follow-up. At presentation and 5-year follow-up, patients with MFRP-associated nanophthalmos exhibited significantly shorter AL and higher SE compared to those without MFRP mutations (all p < 0.001). Central macular thickness (CMT), subfoveal choroidal thickness (SFCT), and retinal nerve fiber layer (RNFL) thickness were significantly greater in the MFRP-associated group at presentation and 5-year follow-up (all p < 0.05). OCT angiography revealed reduced parafoveal VD in the SCP and DCP, as well as decreased foveal and parafoveal VD in the CC in the MFRP group compared to the group without MFRP mutations (all p < 0.05). FAZ areas in the SCP and DCP were also significantly smaller in the MFRP group (p < 0.001 and p = 0.01, respectively). Eyes with MFRP-associated nanophthalmos exhibit significantly higher SE, shorter AL, and more pronounced alterations in retinal structure and microvasculature compared with eyes without MFRP mutations.

AIM: To define the anatomic and functional outcomes of pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling, inverted ILM flap and free ILM patch graft technique for the treatment of myopic macular hole (MH) without retinal detachment. METHODS: Sixty-four eyes of 64 patients who underwent PPV for myopic MH were included. Group 1 consists of patients underwent ILM peeling (n=26), and Groups 2 and 3 consists of patient underwent free ILM patch graft (n=20) and inverted ILM flap procedure (n=18) respectively. Outcomes following surgery were MH closure and best corrected visual acuity (BCVA) in logMAR at 6mo. RESULTS: Closure of MH was obtained in 20 eyes (76.9%) of the Group 1, in 16 eyes (80%) of the Group 2 and in 16 eyes (88.9%) of the Group 3. The mean preoperative and postoperative BCVA was 1.60±0.53 logMAR and 1.27±0.58 logMAR, respectively (P<0.05). There was no significant difference in the postoperative BCVA and anatomical closure rates in the three groups. Although the anatomical closure rate did not differ significantly in the groups, closure of MH tended to be better in the inverted ILM flap technique group at 6mo. CONCLUSION: Different surgical techniques may provide favorable visual and anatomical results for myopic MH surgery. ILM flap techniques offer higher closure rates compared to ILM peeling technique. However, in terms of visual outcomes, the study reveals no difference in three surgical techniques.