Decreased Presence of Mast Cells in the Bursa Premacularis of Proliferative Diabetic Retinopathy.

INTRODUCTION: We previously reported that the intravitreal activities of chymase and tryptase were more increased in the patients with macular hole (MH) and epiretinal membrane (ERM) than in those with proliferative diabetic retinopathy (PDR) and that the source of these serine proteases might be mast cells in the bursa premacularis (BPM). The purpose of this study was to compare the density of mast cells in BPM samples obtained from MH, ERM, and PDR patients. METHODS: BPM and vitreous core samples were first collected during vitrectomy from eyes afflicted with vitreoretinal diseases (MH: 6 eyes, ERM: 3 eyes, and PDR: 9 eyes), and then were stained with hematoxylin, toluidine blue, antibodies against chymase and tryptase, and a terminal deoxynucleotidyl transferase dUTP nick end labeling assay kit. RESULTS: Hematoxylin nuclear staining showed fewer positive-staining cells in the BPM samples obtained from PDR patients than in those obtained from MH and ERM patients. Toluidine blue staining of the BPM revealed metachromasia in the mast cells of the patients with MH and ERM, but not those of the patients with PDR. In addition, immunostaining using anti-chymase and anti-tryptase antibodies showed that the BPM samples were more intensely stained than the vitreous core samples from the patients with MH and ERM and that both tissue samples were poorly stained in the patients with PDR. The apoptotic cells were more frequently observed in the BPM samples from patients with MH than in those from patients with PDR. CONCLUSIONS: These findings indicated that lower activities of chymase and tryptase in the vitreous of PDR patients appeared to be attributable to the decreased presence of mast cells in the BPM. The lack of mast cells in the BPM might be related to the pathogenesis of PDR.

Involvement of Anoikis in Dissociated Optic Nerve Fiber Layer Appearance.

Dissociated optic nerve fiber layer (DONFL) appearance is characterized by dimpling of the fundus when observed after vitrectomy with the internal limiting membrane (ILM) peeling in macular diseases. However, the cause of DONFL remains largely unknown. Optical coherence tomography (OCT) findings have indicated that the nerve fiber layer (NFL) and ganglion cells are likely to have been damaged in patients with DONFL appearance. Since DONFL appearance occurs at a certain postoperative period, it is unlikely to be retinal damage directly caused by ILM peeling because apoptosis occurs at a certain period after tissue damage and/or injury. However, it may be due to ILM peeling-induced apoptosis in the retinal tissue. Anoikis is a type of apoptosis that occurs in anchorage-dependent cells upon detachment of those cells from the surrounding extracellular matrix (i.e., the loss of cell anchorage). The anoikis-related proteins ßA3/A1 crystallin and E-cadherin are reportedly expressed in retinal ganglion cells. Thus, we theorize that one possible cause of DONFL appearance is ILM peeling-induced anoikis in retinal ganglion cells.

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.

A case of tractional retinal detachment associated with congenital retinal vascular hypoplasia in the superotemporal quadrant treated by vitreous surgery.

BACKGROUND: Here we report a case of traction retinal detachment (TRD) associated with congenital retinal vascular hypoplasia localized in the superotemporal quadrant that was treated with vitrectomy. CASE PRESENTATIONS: A 58 year-old female presented with a gradual decrease of visual acuity (VA) and distorted vision in her left eye. She had a past history of amblyopia in her left eye from early childhood, and a previous examination performed at a nearby hospital revealed that the corrected visual acuity (VA) in that eye was 0.15. Upon initial examination, no abnormal findings were observed in her right eye, yet optic-disc traction and macular rotation with a folded TRD extending superotemporally from the macular region was observed in her left eye. Fluorescein fundus angiography showed a retinal nonperfused area localized in the superotemporal quadrant surrounded by a retinal avascular area. The optic disc in her left eye was smaller than that in her right eye. Vitrectomy was performed to remove the proliferative membrane and created an artificial posterior vitreous detachment (PVD). Following surgery, the patient's corrected VA improved from 0.04 to 0.1. CONCLUSIONS: The present case was likely to be TRD caused by PVD in the presence of localized congenital retinal vascular hypoplasia secondary to optic-disc hypoplasia.

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.

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.

Long-Term Follow-Up Changes of Central Choroidal Thickness Thinning after Repeated Anti-VEGF Therapy Injections in Patients with Central Retinal Vein Occlusion-Related Macular Edema with Systemic Hypertension.

PURPOSE: We investigated the thinning of central choroidal thickness (CCT) following intravitreal injections of anti-vascular endothelial growth factor (anti-VEGF) drugs to treat central retinal vein occlusion (CRVO)-related macular edema in patients with and without systemic hypertension (HT) to assess the influence of repeated anti-VEGF therapy and HT on the choroid in CRVO eyes. METHODS: We conducted a retrospective study involving 27 patients with CRVO-related macular edema from January 2014 to July 2017, with follow-ups exceeding 18 months. Visual acuity (VA), central retinal thickness (CRT), and CCT were evaluated before and after initial anti-VEGF drug treatment during follow-up. RESULTS: The mean follow-up period was 35.2 months. Seventeen (63.0%) patients had HT. At 1 month after treatment, VA had improved in 21 (77.8%) patients, and CRT had decreased in 25 (92.6%). At the final visit, 22 (81.5%) showed improved VA, 19 (70.4%) had resolved macular edema, and the CCT had gradually become thinner with additional drug injections in all the patients. Furthermore, the mean CCT in HT patients (209.0 µm) was significantly lower than in non-HT patients (256.1 µm), and the mean injections were 7.8 and 5.3, respectively (p = 0.2067). CONCLUSION: The CCTs were thinner in eyes with HT than in eyes without HT both before and after the repeated anti-VEGF injections.

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.

Involvement of the Retinal Pigment Epithelium in the Development of Retinal Lattice Degeneration.

Lattice degeneration involves thinning of the retina that occurs over time. Here we performed an immunohistological study of tissue sections of human peripheral retinal lattice degeneration to investigate if retinal pigment epithelium (RPE) cells are involved in the pathogenesis of this condition. In two cases of retinal detachment with a large tear that underwent vitreous surgery, retinal lattice degeneration tissue specimens were collected during surgery. In the obtained specimens, both whole mounts and horizontal section slices were prepared, and immunostaining was then performed with hematoxylin and antibodies against glial fibrillary acidic protein (GFAP), RPE-specific protein 65 kDa (RPE65), pan-cytokeratin (pan-CK), and CK18. Hematoxylin staining showed no nuclei in the center of the degenerative lesion, thus suggesting the possibility of the occurrence of apoptosis. In the degenerative lesion specimens, GFAP staining was observed in the center, RPE65 staining was observed in the slightly peripheral region, and pan-CK staining was observed in all areas. However, no obvious CK18 staining was observed. In a monkey retina used as the control specimen of a normal healthy retina, no RPE65 or pan-CK staining was observed in the neural retina. Our findings suggest that migration, proliferation, and differentiation of RPE cells might be involved in the repair of retinal lattice degeneration.

Investigation of scleral thermal injuries caused by ultrasonic pars plana phacoemulsification and aspiration using pig eyes.

PURPOSE: The purpose of this study was to investigate the thermal injuries caused by ultrasonic pars plana phacoemulsification and aspiration (PPPEA) using pig eyes. METHOD: Using a 20-gauge (G) vitrectomy system (Accurus®, Fragmatome; Alcon Laboratories) in both the 'open-tip' and 'closed-tip' techniques, PPPEA was performed in pig eyes and the subsequent thermal injuries generated around the scleral wound were measured by infrared thermal imaging (thermography). Post surgery, the state of the scleral wound was observed under a microscope, and a tissue slice containing the scleral wound was then prepared and observed under an optical microscope. RESULTS: Thermography measurements revealed a slight temperature rise around the scleral wound in the open-tip case, yet a marked temperature rise in the closed-tip case. The scleral wound incision produced by the open tip was linear, while that produced by the closed tip was expanded. Histological examination revealed mild degeneration of the sclera around the wound in the open-tip case, yet marked tissue degeneration by thermal injuries in the closed-tip case. CONCLUSION: Our findings showed that in PPPEA, the temperature of the tip of a 20G vitrectomy system rapidly increases due to the closed-tip technique, thus producing obvious thermal damage to the scleral wound. In order to prevent thermal injuries to the scleral wound during PPPEA, it is important to shorten the time of ultrasonic oscillation during surgery as much as possible while the tip is occluded with nuclear fragments.

A case of silicone oil adhered to the retinal surface via perfluorocarbon liquid.

BACKGROUND: Perfluorocarbon liquid (PFCL) is widely used as an intraoperative heavy tamponade to flatten the retina and is replaced with silicone oil (SO) at the end of the surgery. Due to the long tamponade period, the SO is known to remain attached to the retina at the time of removal, and is commonly termed "sticky oil". The aim of this present study was to report a case of SO stickily attached to the retina via PFCL without tamponade period. CASE PRESENTATION: A 39-year-old male was referred to our hospital due to decreased vision and visual field defect in his right eye. Upon examination, he was diagnosed with rhegmatogenous retinal detachment in that eye. For treatment, he underwent vitrectomy with the use of PFCL and SO. The direct exchange of PFCL with SO resulted in residual subretinal fluid, so we subsequently attempted to remove the SO. However, a SO bubble adhering to the PFCL was visible on the posterior pole. After aspiration of the PFCL beneath the sticky SO, the SO was easily separated and removed from the retina. CONCLUSIONS: Our findings show that SO can become tightly adhered to the retinal surface via PFCL during vitrectomy, and that the sticky SO can be safely removed via aspiration of the PFCL layer underneath the SO.

Optical coherence tomography findings of falciform retinal detachment complicated with persistent fetal vasculature.

BACKGROUND: Falciform retinal detachment (FRD) usually causes pronounced retinal wrinkles, and the prognosis of visual function is poor. In this present study, we report a rare case of FRD in which optical coherence tomography (OCT) findings revealed a relatively good visual function. CASE PRESENTATION: This study involved a 22-year-old female who had previously been diagnosed with FRD at 2 years of age, and who presented with microphthalmus in both eyes with pronounced retinal folds from the optic disc to the inferior-temporal side. Based on the clinical findings, we diagnosed it as persistent fetal vasculature (PFV). We found the visual function in her left eye to be relatively poor, yet from 6 to 22 years of age, the corrected visual acuity in that eye remained at 0.08. Although a nystagmus was present, Goldman perimetry showed a relatively wider visual field than expected. Optical coherence tomography (OCT) findings revealed that the retinal layer structure near the FRD was relatively well maintained, except for the temporal peripheral region. CONCLUSIONS: Our findings reveal that OCT examination can be considered useful for predicting the visual function in cases of FRD.

Development of macular retinoschisis long after the onset of retinal arterial occlusion (RAO): a retrospective study.

BACKGROUND: To describe a retrospective study of macular retinoschisis that developed long after the onset of retinal artery occlusion (RAO) using optical coherence tomography (OCT). METHODS: We describe changes in macular findings and visual acuity (VA) of 29 patients (21 males and 8 females, mean age: 66.1 ± 16.9 years) with RAO (18 branch RAOs [BRAOs] and 11 central RAOs [CRAOs] who visited Osaka Medical College Hospital over an 8-year period based on a medical chart review. RESULTS: The mean VA (logMAR) increased from 1.06 ± 1.08 (CRAO: 2.04 ± 0.99; BRAO: 0.37 ± 0.40) at the first visit to 0.71 ± 0.87 (CRAO: 1.46 ± 0.86; BRAO: 0.18 ± 0.30) at the final visit. Macular OCT revealed swelling or hyper-reflectivity of the inner retina in the early phase of RAO and retinal thinning in the late phase. Among the 29 patients, two patients (a patient with BRAO and a patient with CRAO) developed macular retinoschisis about 1 year after RAO onset. The VA of the patient with BRAO was 20/300 at the first visit, and it improved to 20/25 two days after onset following eye massage and anterior chamber paracentesis. However, his VA worsened, declining from 20/25 to 20/50, and retinoschisis occurred 13 months after RAO onset. The patient with CRAO showed macular changes including small cystoids at the first follow-up visit more than 3 weeks after onset and developed retinoschisis 11 months after the first visit. In addition, two patients with BRAO and one patient with CRAO developed macular changes including small cystoids 3 weeks after onset, with the BRAO complicated by retinal vein occlusion. In the CRAO patient, the cystoid macular edema was resolved 1 month after the first visit. CONCLUSIONS: Macular retinoschisis is unusual, but a possible complication of RAO that can develop long after the onset of the occlusion, potentially resulting in renewed VA deterioration.

Seasonal Variation in Japanese Central Serous Chorioretinopathy.

PURPOSE: We investigate seasonal variations found in patients with central serous chorioretinopathy (CSC). METHODS: We retrospectively investigated 201 CSC patients at the Osaka Medical College Hospital from January 2011 to December 2016 and evaluated their seasonal and monthly distributions. RESULTS: The study population comprised 149 males and 52 females. There were significant seasonal differences in the distribution of patients, with 62 cases in spring, 37 in summer, 59 in autumn, and 43 in winter, and the monthly prevalence of CSC was high in March (n = 24), April (n = 22), and November (n = 23). In addition, seasonal variation of serous retinal detachment (SRD) in the macula could be observed in 12 recurrent CSC cases. CONCLUSIONS: The prevalence of CSC development was the highest in spring. In addition, recurrent SRD in the macula showed seasonal variation in some CSC patients. As factors related to CSC, season and temperature might influence the pathophysiology of CSC.

A case of proliferative diabetic retinopathy in which scintillating particles appeared in the intravitreal cavity after laser photocoagulation.

BACKGROUND: To report a case of proliferative diabetic retinopathy (PDR) exhibiting the appearance of scintillating particles presumed to be crystallin inside the intravitreal cavity after laser photocoagulation. CASE PRESENTATION: A 56-year-old male patient presented at our outpatient clinic after becoming aware of decreased vision in his right eye. Ocular examination performed at the patient's initial visit revealed a massive preretinal macular hemorrhage due to PDR in his right eye. Fundus fluorescein angiography revealed extensive retinal non-perfusion areas and neovascularization in both eyes. However, no opacity was observed in the intravitreal cavity of his left eye. Vitreous surgery was performed on the patient's right eye after ultrasonic phacoemulsification aspiration and intraocular lens implantation. Post surgery, the corrected VA in that eye improved from 0.1 to 1.0. In correlation with the treatment performed on the patient's right eye, we began panretinal photocoagulation on his left eye. Examination performed prior to the patient's third session of panretinal photocoagulation revealed a large number of scintillating particles in the posterior vitreous gel in front of the retina. Examination via slit-lamp microscopy revealed that the particles were of varied hues, and closely resembled a 'Christmas tree' cataract. No posterior vitreous detachment was observed, and since these particles were situated as if captured in the posterior vitreous gel, no eye-movement-associated mobility of the particles was observed. Since the cloudiness was not severe enough to interfere with photocoagulation, additional photocoagulation was performed, and the patient is currently under observation. Six months have now passed since the fourth photocoagulation procedure was performed, and there has been no change in the state of the particles. Optical coherence tomography imaging revealed no change before and after the panretinal photocoagulation. The corrected VA in his left eye has remained at 1.0 during the postoperative follow-up period. CONCLUSIONS: We speculate that the production of crystallin in the retina in this case was triggered by the photocoagulation procedure performed for diabetic retinopathy.

Case of asteroid hyalosis that developed severely reduced vision after cataract surgery.

BACKGROUND: To report our findings in a patient with asteroid hyalosis (AH) who had a severe reduction of his visual acuity following cataract surgery. The vision was improved by vitreous surgery. CASE PRESENTATION: The patient was an 81-year-old man. Following cataract surgery on his left eye, his decimal best-corrected visual acuity (BCVA) was markedly reduced from 0.2 to 0.02. A large number of asteroid bodies (ABs) was observed to be concentrated on the posterior surface of the implanted intraocular lens. Ultrasound B-mode images showed turbidity of the vitreous that was denser in the anterior vitreous where the ABs were concentrated. During vitrectomy, the ABs were observed to be concentrated in the anterior vitreous cavity, and a complete posterior vitreous detachment (PVD) was present. After vitrectomy successfully removed the ABs, the visibility of the fundus improved and the BCVA recovered to 1.0. CONCLUSION: We suggest that the visual impairment after the cataract surgery was due to the concentrated ABs in the anterior vitreous cavity. The clustering of the ABs in the anterior vitreous cavity was most likely caused by the PVD that developed during the cataract surgery.

A case of pseudoxanthoma elasticum with proliferative diabetic retinopathy.

BACKGROUND: To report the case of a patient with pseudoxanthoma elasticum (PXE) and proliferative diabetic retinopathy (PDR), and discuss the relationship between PXE and diabetic retinopathy (DR). CASE PRESENTATION: A 47-year-old man with PXE presented with angioid streaks and DR in both eyes, and bilateral panretinal photocoagulation was performed for treatment. Vitrectomy had previously been performed in his right eye for vitreous hemorrhage due to PDR. Systemic findings included multiple, discrete, symmetrical, small yellow papules bilaterally in the axilla and inguinal region. Examination on presentation showed vitreous hemorrhage in his left eye, and vitrectomy was performed for treatment. Intraoperative findings showed fibrovascular membrane around the optic disc and vascular arcade. A mottled fundus (peau d'orange appearance) associated with angioid streaks was also present, yet there was no evident choroidal neovascularization (CNV). The postoperative course was satisfactory, and corrected visual acuity improved from 0.02 to 0.7 diopters. CONCLUSION: Despite the peau d'orange appearance in both eyes of this case, no CNV was evident. The vitreous hemorrhage was thus attributed to PDR. Moreover, we reviewed the published literature and discuss the relationship between PXE and DR.

Clinical Features of Japanese Patients with Central Retinal Vein Occlusion Complicated by Normal-Tension Glaucoma: A Retrospective Study.

PURPOSE: The association of central retinal vein occlusion (CRVO) with primary open-angle glaucoma (POAG) or ocular hypertension has been reported, and lowering intraocular pressure (IOP) helps to improve the retinal circulation in eyes with CRVO. However, the clinical features of CRVOs with normal-tension glaucoma (NTG) are not well known. Therefore, we investigated Japanese CRVO patients with NTG. METHODS: We retrospectively investigated 234 CRVO patients over 5 years, with follow-ups of more than 12 months, and evaluated the prevalence of glaucoma. RESULTS: Of the 234 CRVO patients, 18 (7.7%) were diagnosed with NTGs (n = 10) or POAGs (n = 8). Seven POAG (87.5%) and 3 NTG (30%) patients had systemic hypertension. At the initial CRVO evaluation, 6 NTGs showed a significantly increased IOP; mean IOP was 13.3 mm Hg before CRVO, 16.2 mm Hg at CRVO, and 13.5 mm Hg at the final visit. CONCLUSIONS: The proportion of NTGs with systemic hypertension was low. IOP of NTG patients was significantly elevated at the initial CRVO evaluation, even in the presence of anti-glaucoma drugs.

Treatment of massive subretinal hematoma associated with age-related macular degeneration using vitrectomy with intentional giant tear.

The purpose of this study was to report the surgical outcomes after creating a 120° intentional giant retinal tear for use in removing hemorrhage and subretinal proliferative tissue in patients with polypoidal choroidal vasculopathy (PCV) or age-related macular degeneration (ARMD). This study involved 12 eyes of 12 patients (10 eyes: PCV, 2 eyes: ARMD). After removal of the lens in phakic eyes, we performed a vitrectomy with artificial posterior vitreous detachment. Subsequently, a 120° intentional giant retinal tear was created in the temporal periphery, the retina was then turned, and the subretinal hemorrhage and proliferative tissue were removed. In order to preserve as much of the retinal pigment epithelium (RPE) as possible, we used a bimanual technique under direct visualization. After stretching the retina by use of perfluorocarbon liquid (PFCL), we performed endophotocoagulation around the tear followed by PFCL/silicone oil exchange. Except for 1 eye in which extensive loss of the RPE occurred, the fundus findings and the visual acuity (VA) improved in all patients. In addition, postoperative VA improved to ≥20/50 in 3 eyes in which the macular RPE was preserved. This surgical procedure is an effective treatment for PCV or ARMD patients with extensive subretinal hemorrhage and proliferative tissue.

Comparison of histopathological findings between idiopathic and secondary epiretinal membranes.

To evaluate the histopathological findings of idiopathic and secondary epithelial membranes (ERMs). This study involved 19 ERM cases that underwent pars plana vitrectomy (PPV). ERM specimens were obtained from each patient during PPV and immediately fixed in 10 % formalin. Paraffin sections were stained with hematoxylin eosin (HE) and immunohistochemical analysis was performed with glial fibrillary acidic protein (GFAP), Ki-67, CD34, and nestin antibodies. The 19 ERM cases included 11 idiopathic ERM cases and 8 secondary ERM cases i.e., 2 eyes that underwent PPV for retinal detachment and 6 eyes that underwent PPV for proliferative diabetic retinopathy. HE staining showed that some of the idiopathic ERM specimens consisted of internal limiting membrane. In contrast, numerous invasive cells were observed in the secondary ERM specimens compared to the idiopathic ERM specimens. Immunohistochemical analysis revealed GFAP-positive cells in 4 of the 11 idiopathic ERMs cases, yet no nestin-, Ki-67-, or CD34-positive cells in those cases. In contrast, there were 4 GFAP-positive cases, 2 Ki67-positive cases, 3 CD34-positive cases, and 7 cases including nestin-positive cells. The findings of this study indicate that there are different histological characteristics between idiopathic and secondary ERM and that mature nestin-positive cells in the retina might be related to secondary ERM formation.