Effects of Angiotensin Receptor Blockers on Streptozotocin-Induced Diabetic Cataracts.

This study aimed to determine the role of oxidative stress produced by the renin-angiotensin system (RAS) in cataract formation in streptozotocin-induced diabetic rats (STZ) using angiotensin II receptor blockers (ARBs). Rats were treated with streptozotocin and orally administered candesartan (2.5 mg/kg/day) or a normal diet for 10 weeks until sacrifice. Cataract progression was assessed through a slit-lamp examination. Animals were euthanized at 18 weeks, and the degree of cataract progression was evaluated. Oxidative stress was also assessed. In STZ-treated rats, lens opacity occurred at 12 weeks. Cataract progression was inhibited in the ARB-treated group compared with the placebo group (p < 0.05). STZ-treated rats exhibited upregulated angiotensin-converting enzyme (ACE) gene expression than control rats. Oxidative stress-related factors were upregulated in the placebo-treated group but suppressed in the ARB-treated group. A correlation coefficient test revealed a positive correlation between ACE gene expression and oxidative stress-related factors and a negative correlation between ACE and superoxide dismutase. Immunostaining revealed oxidative stress-related factors and advanced glycation end products in the lens cortex of the placebo-treated group. The mechanism of diabetic cataracts may be related to RAS, and the increase in focal ACE and angiotensin II in the lens promotes oxidative stress-related factor production.

A Case of Presumed Dyskeratosis Congenita Causing Severe Retinal Vascular Occlusion.

Dyskeratosis congenita (DKC) is a rare, multisystem, bone marrow failure disease characterized by abnormalities such as in the skin, mucosa, nervous system, and lungs. Here we report a rare case of presumed DKC causing total retinal detachment in the right eye and severe peripheral retinal vascular occlusion in the left eye. A 3-year-old boy was presented with vitreous hemorrhage and total retinal detachment in the right eye and was scheduled to undergo vitreous surgery in the right eye and detailed ophthalmologic examination of the left eye under general anesthesia. Since a systemic examination revealed anemia and marked thrombocytopenia, he underwent a detailed pediatric examination. Although genetic testing revealed no significant pathologic mutations, the presence of shortened telomere length and other clinical findings suggested the possibility of DKC. His right eye had severe proliferative vitreoretinopathy, and retinal reattachment was not achieved with vitreous surgery, thus resulting in phthisis bulbi. The left eye showed a wide retinal avascular area in the temporal retina, retinal neovascularization, and hard exudates on fluorescein fundus angiography and was treated with laser photocoagulation using a binocular indirect ophthalmoscopic photocoagulator. Following laser surgery, the new blood vessels regressed, and the visual acuity was maintained at 1.0. The findings in this rare case indicate that DKC can cause severe retinal vascular occlusion, thus leading to vitreous hemorrhage and retinal detachment. Therefore, early detection with fundus examination and early treatment with photocoagulation are important.

Expression of Lymphatic Markers in the Berger's Space and Bursa Premacularis.

We previously reported that the bursa premacularis (BPM), a peculiar vitreous structure located above the macula, contains numerous cells expressing markers of lymphatic endothelial cells, such as podoplanin and LYVE-1. Herein, we examined the expression of lymphatic markers in the Berger's space (BS), BPM, and vitreous core (VC). BS, BPM, and VC specimens were selectively collected in macular hole and epiretinal membrane patients during vitrectomy and were then immunostained with antibodies for podoplanin, LYVE-1, and fibrillin-1 and -2. By visualization using triamcinolone acetonide, the BS was recognized as a sac-like structure with a septum located behind the lens as well as BPM. Those tissues adhered to the lens or retina in a circular manner by means of a ligament-like structure. Immunostaining showed intense expression of podoplanin and LYVE-1 in the BS. Both BS and BPM stained strongly positive for fibrillin-1 and -2. The VC was faintly stained with antibodies for those lymph-node markers. Our findings indicate that both BS and BPM possibly belong to the lymphatic system, such as lymph nodes, draining excess fluid and waste products into lymphatic vessels in the dura mater of the optic nerve and the ciliary body, respectively, via intravitreal canals.

Valsalva retinopathy induced by handstand: a case report.

BACKGROUND: Valsalva retinopathy is known to occur as a sudden preretinal or sub-internal limiting membrane hemorrhage induced by a rapid rise in venous pressure following increased intrathoracic or intraabdominal pressure. Here we report a case of Valsalva retinopathy that was probably induced by straining that occurred due to following a handstand. CASE PRESENTATION: A 15-year-old boy became aware of decreased visual acuity in his left eye immediately after doing a handstand for approximately 10 s during physical education class, and subsequently visited a local clinic on the same day. Upon examination, a vitreous hemorrhage (VH) in the posterior pole of the fundus was found in his left eye, and he was subsequently referred to our department 7 days later. Upon examination, the VH around the optic nerve head of the left eye appeared to be resolved, and an oval-shaped sub-internal limiting membrane (sub-ILM) hemorrhage was found in the superonasal side of the optic nerve head. No abnormalities were observed in the macular area. Four months later, the sub-ILM hemorrhage was found to have spontaneously resolved. Subsequent fluorescein angiography examinations revealed no abnormal findings at the lesion site. CONCLUSIONS: In this patient, we hypothesize that the Valsalva retinopathy was induced by straining that occurred due to a handstand, and that the resultant sub-ILM hemorrhage progressed to VH.

Ciliary body suturing using intraocular irrigation for traumatic cyclodialysis: two case reports.

BACKGROUND: We report two cases (two eyes) of traumatic cyclodialysis with prolonged decrease of intraocular pressure that were successfully treated with surgery by ciliary body suturing using intraocular irrigation. CASE PRESENTATION: This study involved a 17-year-old Japanese boy (patient 1) and a 31-year-old Japanese man (patient 2) in whom cyclodialysis was sustained in one eye after blunt-force ocular trauma from a thrown ball. Because the hypotony maculopathy in both patients did not resolve after conservative treatment, ciliary body suturing was performed. Briefly, a 25-gauge trocar intraocular irrigation needle for vitrectomy was inserted into the vitreous cavity of the injured eye. A lamellar scleral flap was then made, and an incision was created on the sclera while maintaining intraocular pressure. Next, the detached ciliary body was sutured to the sclera under direct vision. The intraocular fluid at the site of cyclodialysis was then rapidly drained from the scleral wound because of elevated intraocular pressure in the vitreous cavity, and the ciliary body was visually recognized through the scleral wound under direct vision, thus allowing a stable suture fixation of the ciliary body to the sclera. Postoperatively, the treated eye in both cases showed improvement of intraocular pressure and visual function. CONCLUSIONS: The surgical method described in this report was found to be effective for draining intraocular fluid at the site of cyclodialysis and for performing a stable suture fixation of the ciliary body to the sclera through the scleral wound under direct vision, and it should be considered advantageous for avoiding intraoperative bleeding and suturing in a blinded manner.

Two cases of diabetic macular edema complicated by an atypical macular hole.

BACKGROUND: Here we report two patients who developed an atypical macular hole (MH) during the treatment course for diabetic macular edema (DME). CASE PRESENTATIONS: Patient 1 was a 73-year-old male. Optical coherence tomography (OCT) revealed perifoveal retinoschisis (RS) in addition to cystoid macular edema and serous retinal detachment (SRD) in his left eye, and that an MH had developed during the clinical course. A convex surface was formed at the MH margin toward the vitreous cavity, and granular shadows were observed in the fluid cuff. Intraoperative findings revealed a thin epiretinal macular membrane (ERM) around the MH. Patient 2 was a 79-year-old male. Although the patient underwent pars plana vitrectomy (PPV) for proliferative diabetic retinopathy (PDR) in both eyes, RS and a thin ERM in addition to SRD was observed in his left eye after surgery, and an MH developed during the clinical course. As in Patient 1, a convex surface was formed at the fluid cuff margin toward the vitreous cavity. CONCLUSIONS: Both patients had persistent DME, SRD, RS, and a thin ERM before the development of the MH. OCT revealed the formation of a convex surface at the MH margin toward the vitreous cavity, suggesting that the fragility of the layered structure of the retina combined with tangential retinal traction may have been involved in the atypical MH form.

Effects of an Aquaporin 4 Inhibitor, TGN-020, on Murine Diabetic Retina.

PURPOSE: To investigate the effect of a selective aquaporin 4 (AQP4) inhibitor, 2-(nicotinamide)-1,3,4-thiadiazole (TGN-020), on the expression of vascular endothelial growth factor (VEGF) and reactive oxygen species (ROS) production, as well as on the retinal edema in diabetic retina. METHODS: Intravitreal injections of bevacizumab, TGN-020, or phosphate-buffered saline (PBS) were performed on streptozotocin-induced diabetic rats. Retinal sections were immunostained for anti-glial fibrillary acidic protein (GFAP), anti-AQP4, and anti-VEGF. Protein levels of VEGF from collected retinas were determined by Western blot analysis. In addition, retinal vascular leakage of Evans Blue was observed in the flat-mounted retina from the diabetic rats in the presence or absence of TGN-020. Volumetric changes of rat retinal Müller cells (TR-MUL5; transgenic rat Müller cells) and intracellular levels of ROS were determined using flow cytometry analysis of ethidium fluorescence in the presence or absence of TGN-020 or bevacizumab under physiological and high glucose conditions. RESULTS: In the diabetic retina, the immunoreactivity and protein levels of VEGF were suppressed by TGN-020. AQP4 immunoreactivity was higher than in the control retinas and the expressions of AQP4 were co-localized with GFAP. Similarly to VEGF, AQP4 and GFAP were also suppressed by TGN-020. In the Evans Blue assay, TGN-020 decreased leakage in the diabetic retinas. In the cultured Müller cells, the increase in cell volumes and intracellular ROS production under high glucose condition were suppressed by exposure to TGN-020 as much as by exposure to bevacizumab. CONCLUSION: TGN-020 may have an inhibitory effect on diabetic retinal edema.

Spontaneous Closure of the Macular Hole in a Patient with Acquired Vitelliform Lesion.

In this paper, we report an extremely rare case of spontaneous closure of a macular hole (MH) that developed in a patient in whom acquired vitelliform lesion (AVL) occurred after vitrectomy for atopic retinal detachment (ARD). A 32-year-old male developed ARD in both eyes, and retinal reattachment was achieved after vitrectomy. Five years after surgery, optical coherence tomography showed localized serous retinal detachment (SRD) and a granular lesion with a higher brightness in the subretinal fluid, thus leading to the diagnosis of AVL. One month later, an MH developed, and a follow-up examination performed 6 weeks later revealed that the MH had spontaneously closed and the SRD decreased. In the fovea, fluorescein angiography revealed a window defect due to atrophy of the retinal pigment epithelium (RPE). These findings in this present case suggest the possibility that RPE dysfunction was involved in the development of AVL and MH.

Clinical Features of Vitreomacular Traction Syndrome with Peripheral Vitreoretinal Adhesion.

PURPOSE: To retrospectively review and analyze the clinical and imaging data of patients with vitreomacular traction syndrome (VMTS) with strong peripheral vitreoretinal adhesion. SUBJECTS AND METHODS: This retrospective case-series study involved 4 eyes of 4 VMTS patients with vitreoretinal adhesion in both the macular region and the periphery who underwent vitreous surgery. In all 4 cases, preoperative refraction, fundoscopic findings, optical coherence tomography (OCT) findings, and intraoperative findings were evaluated. RESULTS: The preoperative fundoscopy and OCT findings revealed fibrous membranes around the optic nerve head in 3 eyes. Thickened posterior vitreous membranes extending from the posterior pole to the periphery were observed in all eyes. Apparent VMTS or epimacular membrane was also found in the fellow eyes of 2 patients. The preoperative refractive errors ranged from +0.5 diopters (D) to +2.75 D (mean, +1.13 D). Intraoperatively, a thickened posterior vitreous membrane was found strongly adhered to the retina in the macula regions, optic nerve head, and periphery. In 2 eyes, when artificial posterior vitreous detachment (PVD) was created, an iatrogenic tear developed in the periphery. CONCLUSION: The features of VMTS that cause strong peripheral vitreoretinal adhesion include the preoperative presence of a thickened posterior vitreous membrane over a wide area, hypermetropia, and a short axial length.

Rhegmatogenous retinal detachment with a giant tear located in the intermediate periphery: Two case reports.

RATIONALE: We experienced 2 cases of retinal detachment (RD) with giant tears located in the intermediate periphery of the fundus. In this case report, we investigated the clinical characteristics in these 2 cases. PATIENT CONCERNS AND DIAGNOSES: Case 1 involved a 63-year-old male, who became aware of metamorphopsia and decreased visual acuity (VA) in his left eye. Upon examination, he was diagnosed with a giant tear at the margin of the intermediate peripheral lattice degeneration. Case 2 involved a 54-year-old male, who became aware of decreased VA in his right eye. Upon examination, he was diagnosed with vitreous hemorrhage and a giant tear located in the upper intermediate periphery. In these 2 cases, there was no obvious previous or familial history. INTERVENTIONS: In both cases, reattachment was achieved by performing vitrectomies. OUTCOMES: These 2 cases were characterized by the refraction being close to emmetropia due to the flat corneal curvature, even though there was a long axial length and the eyeballs were spherically large. In both cases, the postoperative clinical course outcome was favorable and no complication occurred LESSONS:: Our findings indicate that intermediate peripheral giant tears may occur in spherically large eyeballs, and that vitreous surgery is effective in such cases. Since the risk of the onset of RD in the fellow eye is thought to be high, strict postoperative follow-up is necessary.

Familial exudative vitreoretinopathy complicated with full thickness macular hole: A case report.

RATIONALE: To report a case of familial exudative vitreoretinopathy (FEVR) complicated with full-thickness macular hole (FTMH). PATIENT CONCERNS: A 39-year-old male presented after becoming aware of metamorphopsia in his left eye. DIAGNOSES: Fundus examination showed a retinal avascular area, retinal vascular abnormality, and yellow exudation at the peripheral retina in both eyes. Optical coherence tomography findings revealed impending MH (IMH) due to posterior vitreous detachment (PVD) in his left eye. Despite of the occurrence of spontaneous complete PVD, an FTMH developed at 4 months after the onset of IMH. INTERVENTIONS: To treat the FTMH, vitreous surgery was performed. Intraoperative findings revealed that the thick posterior vitreous membrane (PVM) had no adhesions with the edge of the FTMH. However, a thin epiretinal membrane (ERM) was observed around the MH. OUTCOMES: Postoperatively, the FTMH was closed, and the patient's corrected visual acuity improved from (0.4) to (0.8). LESSONS: In this present case, an IMH developed via traction by a thick PVM, characteristic of FEVR, with FTMH then developing via traction by a thin ERM. Our findings reveal that it is vital to fully understand these anatomical features before performing vitreous surgery for FTMH complicated with FEVR.

A Case of a Ruptured Eyeball Caused by High-Pressure Water Jets.

To report the case of a ruptured eyeball caused by high-pressure water jets. In this study, the right eye of a 49-year-old male was injured by high-pressure water jets while he was engaged in demolition work. Upon examination, remarkable hyphema and vitreous hemorrhage were observed in the injured eye. After treating the patient's right eye with vitrectomy, in addition to lens subluxation and iridodialysis, retinal detachment was observed at the nasal inferior. The edge of the retinal break was found to be incarcerated into the nasal sclera rupture wounds. The findings of this study indicate that direct exposure to high-pressure water jets can cause a rupture of the eyeball. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:451-455.].

Idiopathic macular hole with asteroid hyalosis: Two case reports.

INTRODUCTION: Asteroid hyalosis (AH) is characterized by mild vitreous-body liquefaction and a reduced likelihood of posterior vitreous detachment (PVD). Here, we report the clinical features of 2 cases of macular hole (MH) in eyes with AH. The extent of retinal vitreous adhesion at the time of vitreous surgery, the presence or absence of iatrogenic retinal breaks, and the postoperative course was examined in regard to the association with AH. CASE PRESENTATION: Case 1 involved a 67-year-old female with decreased visual acuity in her left eye. Although preoperative optical coherence tomography examination revealed complete PVD with operculum around the fovea central region, vitreoretinal adhesion was quite strong starting at the midperiphery of the fundus, and an iatrogenic retinal break was formed at the inferior site during vitreous surgery. Endophotocoagulation was performed, and no onset of retinal detachment (RD) postsurgery was observed. Case 2 involved a 74-year-old male with metamorphopsia in his right eye. Preoperative perifoveal PVD was observed, yet vitreoretinal adhesion was strong starting at the midperiphery of the fundus and multiple iatrogenic retinal breaks had formed on the inferior, superior, and temporal sites. Moreover, RD occurred during surgery. Endophotocoagulation and gas tamponade was performed; however, postoperative RD requiring multiple reoperations occurred. CONCLUSION: As with normal MH, MH with AH is thought to be caused by perifoveal PVD, yet as the vitreoretinal adhesion was found to be quite strong starting at the midperiphery of the fundus, we decided to keep the artificial PVD within a range where adhesion was loose.

Case Report of a Family Affected by Stickler Syndrome in Which Rhegmatogenous Retinal Detachment Occurred in Five Eyes of Three Siblings.

PURPOSE: Stickler syndrome is an autosomal dominant inherited disorder that is well known to be highly associated with the development of rhegmatogenous retinal detachment. In this study, we report the case of a family affected by Stickler syndrome in which rhegmatogenous retinal detachment developed in 5 eyes of 3 siblings. CASE SERIES: For treatment, we performed vitreous surgery on 1 eye of the eldest son, and bilateral scleral buckling surgery on the 2 younger children. A good postoperative outcome was obtained on the 4 eyes that underwent scleral buckling surgery, yet the prognosis was poor on the 1 eye that underwent vitrectomy due to redetachment of the retina and corneal complication. Since vitreous surgery was quite difficult due to strong vitreoretinal adhesion, we created an artificial posterior vitreous detachment via the bimanual technique combined with encircling. For the scleral buckling surgery, broad scleral extrusion was needed to seal multiple retinal breaks. CONCLUSIONS: The findings of this study showed a high prevalence of rhegmatogenous retinal detachment in a single family with Stickler syndrome. In these cases, scleral buckling surgery was effective for treating the detached retina, and some prophylactic treatment, such as laser photocoagulation to prevent the occurrence of rhegmatogenous retinal detachment, should be considered for such cases in the future.