Publications by authors named "Nobuhiko Shiraki"
Article Synopsis
- The study examined the impact of internal limiting membrane (ILM) peeling during vitrectomy on visual outcomes for patients with vitreous hemorrhage due to retinal vein occlusion and varying levels of macular ischemia.
- Results showed that although both procedures led to improved visual acuity, non-ILM peeling provided better visual outcomes, especially in patients without ischemia.
- The findings suggest that ILM peeling should be avoided in cases with pre-existing macular ischemia to prevent worsening visual results post-surgery.
Article Synopsis
- Severe Proliferative Diabetic Retinopathy (PDR) can lead to vision-threatening conditions like macular tractional retinal detachment (MTRD) due to the formation of fibrovascular membranes (FVM).
- A case involving a 68-year-old woman with PDR underwent vitrectomy where complications arose due to unnoticed separation of the inner and outer retina during membrane removal, which was complicated by pre-existing retinal holes.
- The surgery successfully reattached the retina and improved the patient's vision, which was maintained for 26 months, highlighting the need for caution during surgical procedures to manage tractional retinoschisis.
Article Synopsis
- The study aimed to examine how volume analysis from optical coherence tomography (OCT) relates to the worsening of diseases like Vogt-Koyanagi-Harada disease (VKHD) and sympathetic ophthalmia (SO).
- Conducted at Osaka University Hospital, the research involved analyzing OCT scans of patients, focusing on specific measurements of choroidal vessel structure to assess their correlation with disease severity.
- Results indicated that certain choroidal volume measurements could effectively predict disease recurrence in VKHD and SO patients, suggesting that OCT volume analysis could serve as useful biomarkers for monitoring these conditions.
Article Synopsis
- Outer retinal degenerations like age-related macular degeneration (AMD) involve damage to photoreceptors and retinal pigment epithelium (RPE), with macrophages clustering at these damaged areas, but their roles are not fully understood, especially in humans.
- The study found that a specific group of microglia expressing galectin-3 is active in areas of retinal degeneration, and when galectin-3 was removed, it resulted in more photoreceptor loss and RPE damage, highlighting its protective function.
- Additionally, signals from Trem2 were shown to guide microglial movement to damaged sites and increase galectin-3 expression, suggesting that enhancing this pathway could offer new treatment strategies for retinal degeneration in AMD patients.
Background: Retinal nonperfusion is a significant cause of vision loss in patients with proliferative diabetic retinopathy (PDR). Therefore, reperfusion of a nonperfusion has been a matter of strong interest, but few previous studies have demonstrated the potential benefits of reperfusion.
Case Reports: Here, we report longitudinal optical coherence tomography angiographic analysis of two cases of PDR, in which the retinal neovascularization (RNV) that developed in response to retinal ischemia formed anastomoses with pre-existing physiological retinal vessels, resulting in both superficial and deep capillary reperfusion within the nonperfusion.
Optical coherence tomography angiography imaging in peripheral commotio retinae: A case report.
Am J Ophthalmol Case Rep
December 2023
Purpose: We present a case of traumatic commotio retinae (CR), in which blood flow was evaluated using optical coherence tomography angiography (OCTA).
Observations: An 18-year-old Japanese man presented with traumatic retinal detachment and CR in his left eye, which had been hit by a handball. Fundus examination revealed peripheral retinal tear extending from the 1 to 3 o'clock position with retinal detachment, and CR near the area of tear.
Purpose: To evaluate the influence of tamponade on the visual and anatomic outcomes of pars plana vitrectomy for myopic traction maculopathy (MTM).
Design: Multicenter, retrospective clinical cohort study.
Methods: Consecutive eyes that underwent vitrectomy for advanced MTM with tamponade of air, sulfur hexafluoride (SF), or perfluoropropane (CF) or without tamponade with a minimum follow-up of 12 months were included.
Article Synopsis
- The study investigates the occurrence, causes, risk factors, and treatment results of postoperative macular holes (MH) following surgery for myopic traction maculopathy (MTM) using pars plana vitrectomy (PPV).
- Out of 207 patients observed over an average of 25.9 months, 11.6% developed postoperative MH, with identified risk factors including male gender, thinner preoperative choroidal thickness, and the use of indocyanine green during surgery.
- Treatment methods varied, with an overall macular hole closure rate of 83%; however, patients who developed MH had significantly poorer visual outcomes compared to those who did not.
Purpose: To investigate the outcomes of intravitreal aflibercept and gas injections for submacular hemorrhage (SMH) associated with polypoidal choroidal vasculopathy (PCV).
Methods: We retrospectively reviewed the medical records of 22 eyes with SMH secondary to PCV that underwent intravitreal aflibercept and 100% perfluoropropane (0.3-0.
Article Synopsis
- A study was conducted to assess macular vessel tortuosity through optical coherence tomography angiography (OCTA) and its impact on visual outcomes in patients undergoing surgery for epiretinal membrane (ERM).
- The study involved 22 patients who underwent standard vitrectomy and were monitored using OCTA for 6 months post-surgery, focusing on the length and branching of retinal vessels.
- Results showed that changes in vessel shape were correlated with improvements in visual acuity over time, indicating that more linear retinal vessels after surgery were linked to better visual outcomes.
Article Synopsis
- Microglia are the immune cells in the central nervous system, and their development in the retina is not well understood.
- Researchers used human-induced pluripotent stem cells to create eye-like organoids that mimic early eye development and discovered that microglia-like cells naturally form in these structures.
- These microglia-like cells have unique traits, indicating that the eye may have its own immune system that operates independently from the rest of the body’s immune system and blood vessels.
Article Synopsis
- A 56-year-old woman with sudden vision loss in her left eye was diagnosed with ocular toxocariasis after presenting symptoms resembling acute endophthalmitis and hyphema, which is a type of bleeding in the eye.
- Despite initial emergency surgery showing severe eye damage and negative cultures, tests revealed positive results for Toxocara canis, indicating a parasitic infection linked to her history of eating undercooked beef.
- Treatment with oral albendazole and prednisone led to significant recovery, restoring her vision, and suggesting that ocular toxocariasis should be considered in similar clinical cases.
Purpose: To investigate the long-term outcomes of pars plana vitrectomy (PPV) with fovea-sparing internal limiting membrane (ILM) peeling (FSIP) and standard ILM peeling for myopic traction maculopathy (MTM).
Design: Retrospective case series.
Participants: A total of 102 eyes of 96 consecutive patients who underwent primary PPV for MTM and were followed up for at least 12 months.
Purpose: To investigate the intraocular lens (IOL) position and refractive outcomes after cataract surgery and phacovitrectomy using swept-source anterior segment OCT (SS-ASOCT).
Design: Retrospective case series.
Participants: Patients underwent cataract surgery (group A: 34 eyes), phacovitrectomy without gas tamponade (group B: 20 eyes), and phacovitrectomy with gas tamponade (group C: 22 eyes).
Article Synopsis
- * A retrospective analysis of 21 patients showed that certain SS-OCT parameters, particularly DRIL length and disruptions in retinal structures, correlated positively with best-corrected visual acuity (BCVA) at 1, 3, and 6 months post-surgery.
- * Results indicated that a DRIL of 500 µm or longer one month after surgery led to significantly poorer visual acuity outcomes, establishing the potential of DRIL as an early predictor of postoperative visual results.
We investigated changes in retinal vascular area and the foveal avascular zone (FAZ) after intravitreal aflibercept in diabetic macular edema (DME) and the association of these changes with visual outcomes. The retinal vascular area in the superficial capillary plexus (SCP) and the deep capillary plexus (DCP) and the FAZ area were measured using optical coherence tomography angiography (OCTA) in 23 eyes of 23 patients with DME, before and after intravitreal aflibercept. Overall, there was no significant change in retinal vascular area or FAZ.
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- The study examined refractive errors following phacovitrectomy for two conditions: rhegmatogenous retinal detachment (RRD) and epiretinal membrane (ERM) in a total of 202 eyes.
- Results showed that patients with RRD experienced a greater myopic shift post-surgery compared to those with ERM, with significant differences in the refractive prediction and absolute prediction errors.
- Adding +0.5 D to the predicted refractive power for patients with RRD effectively reduced these errors, suggesting that this adjustment can help manage postoperative myopia.
Purpose: The aim of this study was to investigate the efficacy of pars plana vitrectomy with inverted internal limiting membrane (ILM) insertion for macular hole retinal detachment (MHRD) in high myopia.
Methods: We studied 49 eyes of 49 consecutive patients who underwent vitrectomy for MHRD and were followed for more than 12 months postoperatively. Eyes that underwent vitrectomy with inverted ILM insertion from October 2013 to August 2015 were compared with eyes that underwent standard ILM peeling from October 2006 to September 2013.
Purpose: To compare the anatomic and functional outcomes of pars plana vitrectomy (PPV) for treating rhegmatogenous retinal detachments (RRDs) between two groups with and without postoperative prone positioning.
Methods: This retrospective cohort study included 142 eyes of 142 patients with a primary RRD. All patients underwent PPV with 20% sulfur hexafluoride gas tamponade and were divided into two groups: the groups that did and did not maintain a prone position postoperatively.
Aims/introduction: To clarify the association between perioperative variables and postoperative bleeding in pars plana vitrectomy for vitreous hemorrhage in diabetic retinopathy.
Materials And Methods: The present retrospective study enrolled 72 eyes of 64 patients who were admitted to Osaka University Hospital between April 2010 and March 2014, and underwent vitrectomy for vitreous hemorrhage as a result of diabetic retinopathy.
Results: Postoperative bleeding developed in 12 eyes.
Purpose: Our purpose was to report the initial clinical experience of intraoperative B-scan ultrasonography in combination with 25-gauge pars plana vitrectomy for severe open globe injury with hemorrhagic retinal and choroidal detachment.
Methods: Six eyes of six consecutive patients with severe open globe injury underwent intraoperative B-scan ultrasonography and 25-gauge pars plana vitrectomy at Osaka University Hospital in Japan. The feasibility of intraoperative B-scan ultrasonography, best-corrected visual acuity (BCVA), retinal reattachment, and intraoperative and postoperative complications were evaluated.
Retinal thickness in parafoveal subfields and visual acuity after vitrectomy for macula-off rhegmatogenous retinal detachment repair.
Graefes Arch Clin Exp Ophthalmol
September 2017
Purpose: To investigate retinal thickness in the central and parafoveal subfields, including segmented analysis of the inner and outer retinal layers, after vitrectomy for macula-off rhegmatogenous retinal detachment (RRD) repair.
Methods: Twenty-four eyes of 24 patients who underwent primary vitrectomy for macula-off RRD repair were enrolled in this study. Spectral-domain optical coherence tomography examination and best-corrected visual acuity (BCVA) measurements were performed at 1, 3, and 6 months after vitrectomy.
Purpose: To investigate microvascular changes in the superficial capillary plexus (SCP) and deep capillary plexus (DCP) in eyes with resolved branch retinal vein occlusion (BRVO) and their association with best-corrected visual acuity (BCVA).
Methods: Eighty-five eyes (82 consecutive patients) with BRVO after resolution of the macular edema were retrospectively evaluated. All patients underwent optical coherence tomography angiography (OCTA) for assessment of microvascular changes, including capillary telangiectasia, microaneurysm, and disruption of the foveal avascular zone (FAZ).
Purpose: To establish geometrically based methods for simulating panretinal laser photocoagulation (PRP) for the photocoagulation index.
Methods: A formula for calculating the curved surface area of a spherical dome was used for the simulation. If the radius of the dome is c and the height of the dome is h, then the curved surface area (S) of the dome is S = π (c2 + h2).