A case of herpes zoster ophthalmicus with optic neuritis of the total length of the optic nerve in the orbital space and ischemic optic neuropathy.

Purpose: We herein report a case of optic neuritis and ischemic optic neuropathy associated with herpes zoster ophthalmicus and decreased visual acuity. Observations: A 65-year-old man with no special medical history had a headache on the right side in December 2019, and a few days later, a facial rash appeared on the same side. A dermatologist diagnosed him with herpes zoster ophthalmicus and started antiviral drug therapy. On the same day, he was referred to a local ophthalmologist and was found to have inflammatory signs in his right cornea and conjunctiva. The next day, when he visited the ophthalmologist again, he had decreased visual acuity, optic disc swelling, and fundus hemorrhaging in his right eye, so he was referred to our department. At the first visit to our department, his best-corrected visual acuity was light sense OD, 1.0 OS. His right fundus showed optic disc swelling, spotted fundus hemorrhaging, and dilation/tortuosity of the retinal vein. Fluorescein angiography showed the near absence of optic disc filling as well as delayed retinal vein perfusion in his right eye, and magnetic resonance imaging confirmed high signals in the total length of the right optic nerve in the orbital space using the short inversion-time inversion recovery method. Based on these findings, we diagnosed him with optic neuritis and ischemic optic neuropathy associated with inflammation of the orbital part caused by herpes zoster ophthalmicus. We started systemic administration of antiviral drugs (acyclovir) and oral steroid. However, after treatment, his visual acuity improved only to hand motion OD, and the fundus appearance was ultimately optic atrophy OD. Conclusion and Importance: Various complications can occur with herpes zoster ophthalmicus, however, few reports have described cases of herpes zoster ophthalmicus associated with optic neuritis and ischemic optic neuropathy. Therefore, there is no consensus concerning the ideal treatment for these conditions. By referencing cases involving issues such as orbital apex syndrome and optic neuritis caused by herpes zoster ophthalmicus, antiviral drugs and oral steroids were administered, but the prognosis of the visual acuity was poor.

Racemose hemangioma complicated with macular macroaneurysm rupture.

PURPOSE: To describe a rare case of racemose hemangioma which developed spontaneous macular macroaneurysm (MA) rupture and vitreaous hemorrhage. OBSERVATIONS: A 29-year-old healthy asian female visited our hospital and a racemose hemangioma was found in the left eye. At presentation, the best corrected visual acuity (BCVA) was 30/20 in her left eye. At 9 years after the first visit, MA-like lesion was noted in the macular area. After that, vitreous and subretinal hemorrhage appeared in the left eye. The patient underwent simultaneous vitrectomy and cataract surgery, but vitreous re-hemorrhage occurred two days after the operation. To avoid re-hemorrhage, silicone oil (SO) tamponade was added in the second vitrectomy. Two years after the second operation, SO was removed and postoperative BCVA in the left eye was 20/200 without re-bleeding in the vitreous. CONCLUSIONS AND IMPORTANCE: Although retinal hemorrhages have been reported in the patients with a racemose hemangioma, in our case the macular MA rupture occurred at 9 years after the first visit. Congenital retinal arteriovenous anastomosis can show a change in vascular shape in some cases, thus it is important to observe carefully.

A Case of Cyclodialysis after Microhook Trabeculotomy Treated with Vitreous Surgery.

We report a case of cyclodialysis with decreased visual acuity after microhook trabeculotomy (mTLO) successfully treated by vitreous surgery. A 41-year-old man had been medically treated for primary open-angle glaucoma in both eyes. He was scheduled to undergo mTLO due to progression of visual field impairment and unstable intraocular pressure in his right eye. His preoperative best-corrected visual acuity (BCVA) was 0.4 OD, and the intraocular pressure was unstable, ranging from 12 to 27 mm Hg. On the day after the operation, a shallow anterior chamber developed, and a low intraocular pressure occurred. His visual acuity continued to decrease, and cyclodialysis was confirmed by ultrasonic biomicroscopy. No improvement was obtained with medical treatment, and his BCVA dropped to 0.08 OD, while his intraocular pressure remained at 2-3 mm Hg. Three months later, a second surgery was performed by combining cataract surgery with intraocular lens implantation, vitrectomy, cryopexy for the pars plana of the ciliary body, and 20% SF6 gas tamponade. Two weeks after the reoperation, the intraocular pressure had been normalized to 12 mm Hg, and the BCVA had returned to 0.3. We successfully treated cyclodialysis as a complication after mTLO by vitreous surgery that led to the recovery of the visual acuity and intraocular pressure.

The protective effect of astaxanthin on the ganglion cell complex in glutamate/aspartate transporter deficient mice, a model of normal tension glaucoma, analyzed by spectral domain-optical coherence tomography.

Astaxanthin (AST), a natural marine carotenoid, possess a wide variety of biological functions. In particular, as a strong antioxidant, AST effectively scavenges oxygen free radicals and reduces oxidative stress. In addition, recent in vitro studies have suggested that AST attenuates glutamate-induced apoptosis and cytotoxicity. The glutamate/aspartate transporter (GLAST) deficient (GLAST-/-) mouse is a mouse model of normal tension glaucoma (NTG) caused by both the glutamate neurotoxicity and oxidative stress in the retina. In the present study, we investigated the effects of AST on the ganglion cell complex, indicator of glaucomatous structural damage, using spectral domain-optical coherence tomography. As a result, AST significantly attenuated the thinning of ganglion cell complex in GLAST-/- mice in comparison to an AST-free control group. Our results suggest the possibility that AST has protective effects against glutamate neurotoxicity and oxidative stress in the retina. At present, the only treatment for NTG that is available in the clinical setting is to reduce the IOP as much as possible. Thus, our results suggest that AST supplementation may be effective for some types of NTG in which glutamate neurotoxicity and oxidative stress are involved.

A spectral-domain optical coherence tomographic analysis of Rdh5-/- mice retina.

PURPOSE: To investigate the longitudinal findings of spectral-domain optical coherence tomography (SD-OCT) in relation to the morphologic features in Rdh5 knockout (Rdh5-/-) mice. MATERIALS AND METHODS: The mouse retina was segmented into four layers; the inner retinal (A), outer plexiform and outer nuclear (B), rod/cone (C), and retinal pigment epithelium (RPE)/choroid (D) layers. The thickness of each retinal layer of Rdh5-/- mice was longitudinally and quantitatively measured at six time points from postnatal months (PM) 1 to PM6 using SD-OCT. Age-matched C57BL/6J mice were employed as wild-type controls. The data were statistically compared using Student's t-test. The fundus appearance was assessed, histologic and ultrastructural examinations were performed in both groups. RESULTS: Layers A and B were significantly thinner in the Rdh5-/- mice than in the wild-type C57BL/6J mice during the observation periods. Layers C and D became thinner in the Rdh5-/- mice than in the wild-type mice after PM6. Although no abnormalities corresponding to whitish fundus dots were detected by SD-OCT or histologic examinations, the intracellular accumulation of low-density vacuoles was noted in the RPE of the Rdh5-/- mice by electron microscopy. The photoreceptor nuclei appeared less dense in the Rdh5-/- mice than in the wild-type mice. DISCUSSION: The results from the present study suggest that although it is difficult to detect qualitative abnormalities, SD-OCT can detect quantitative changes in photoreceptors even in the early stage of retinal degeneration induced by the Rdh5 gene mutation in mice.

Excess Glutamate May Cause Dilation of Retinal Blood Vessels in Glutamate/Aspartate Transporter-Deficient Mice.

PURPOSE: To investigate the longitudinal findings of fundus features and spectral-domain optical coherence tomography (SD-OCT) to characterize the morphologic features in a mouse model of defective glutamate/aspartate transporter (GLAST-/- mice). MATERIALS AND METHODS: The fundus findings and SD-OCT images were longitudinally recorded at five time points from postnatal (P) 22 to P156 in GLAST-/- mice. As a control wild type, age-matched C57BL/6J mice were employed. The mouse retina was subdivided into five layers, and the thickness of each layer was longitudinally measured by InSight® using SD-OCT pictures. The SD-OCT findings were compared with the histologic appearances. The diameter of the retinal blood vessels was measured by the ImageJ® software program using SD-OCT images. The data were statistically compared between both age-matched mouse groups. RESULTS: The retinal blood vessels appeared more dilated in GLAST-/- mice than in wild-type mice. This tendency was statistically significant at all time points after P44 by analyses using SD-OCT images. The ganglion cell complex (GCC) and outer nuclear layer (ONL) were significantly thinner in GLAST-/- mice at all time points after P80 than in the wild-type mice. This tendency was more clearly indicated by SD-OCT than histologic sections. DISCUSSION: In the present study, we found for the first time the dilation of the retinal blood vessels and the thinning of the ONL in GLAST-/- mice, in addition to the thinning of the GCC.

The findings of optical coherence tomography of retinal degeneration in relation to the morphological and electroretinographic features in RPE65-/- mice.

PURPOSE: Mutations of the gene encoding RPE65 cause Leber congenital amaurosis (LCA) retinitis pigmentosa (RP). The optical coherence tomography (OCT) is increasingly utilized to noninvasively evaluate various types of retinal diseases, including RP. The present study was conducted to characterize the OCT findings of the RPE65-/- mice-an animal model of LCA and RP-in relation to the morphological features based on histological and electron microscopic findings as well as electroretinography (ERG) features. MATERIALS AND METHODS: RPE65-/- mice were employed as a model of retinal degeneration. C57BL/6J mice were used as a wild-type control. OCT was performed on the RPE65-/- mice from postnatal day (P) 22 to 170. The longitudinal changes in the OCT images and fundus pictures were analyzed both qualitatively and quantitatively in comparison to those of C57BL/6J mice. The OCT images were also compared to the histological and electron microscopic findings. Full field combined rod and cone ERG was performed to analyze the relationship between morphology based on OCT and the amplitudes of the a- and b-waves. RESULTS: In the RPE65-/- mice, the photoreceptor rod and cone layer appeared as a diffuse hyperreflective zone contiguous with the inner segment ellipsoid zone (IS-EZ) on OCT, even on P22, whereas the IS-EZ and interdigitation zone were clearly identified in the age-matched C57BL/6J mice. The histological analyses revealed that the regular arrangement of the photoreceptor inner and outer segments was gradually lost in the RPE65-/- mice. On electron microscopy, most of the rod outer segments were degenerated from P21 to P35, whereas outer segments became variably shorter after P49 although ultrastructure appeared to normalize. The thickness of the outer nuclear layer of RPE65-/- mice was slowly and progressively reduced in comparison to C57BL/6J mice. Although the thickness of the inner and outer segment layer of RPE65-/- mice was significantly decreased in comparison to C57BL/6J mice, the change was not progressive, at least until P170. Even at P35, the amplitudes of both a- and b-waves on ERG were severely deteriorated in comparison to those of C57BL/6J mice. Mottled depigmented spots appeared throughout the fundus in RPE65-/- mice after P72, and were detected as hyperreflective deposits under the retinal pigment epithelium on OCT. DISCUSSION: The pathological changes in the inner and outer segments layer of RPE65-/- mice were identified as diffuse hyperreflective changes on OCT. The rod outer segments showed degeneration in the early postnatal periods but became morphologically normalized in the disc structure after P49, although the sizes of the length of the rod outer segments were variable. OCT could not qualitatively differentiate the early degeneration of rods from the late variability in size of rods. Although the morphology of the photoreceptor outer segments was relatively preserved in the RPE65-/- mice, the amplitudes of ERG were severely disturbed. These structural and functional deficits may be derived from the defective supply of 11-cis-retinol to the photoreceptors.

The Spectral-Domain Optical Coherence Tomography Findings Associated with the Morphological and Electrophysiological Changes in a Rat Model of Retinal Degeneration, Rhodopsin S334ter-4 Rats.

PURPOSE: To characterize the spectral-domain optical coherence tomography (SD-OCT) findings of the rhodopsin S334ter transgenic rats (line 4) in relation to the morphologic and electroretinographic features. MATERIALS AND METHODS: Rhodopsin S334ter transgenic rats (line 4) were employed as a model of retinal degeneration. The Sprague-Dawley (SD) rats were used as a wild-type control. SD-OCT (Micron IV®; Phoenix Research Labs, Pleasanton, CA, USA) was performed on the S334ter rats (line 4) from postnatal days (P) 13-110. The longitudinal changes of the SD-OCT images were analyzed both qualitatively and quantitatively in comparison to those of SD rats. The SD-OCT images were also compared to the histological and electron microscopic findings from examination performed on P 22, 36, and 61. Full field combined rod and cone electroretinography (ERG) was performed and the relationship between the thickness of the retinal sublayers and the amplitudes of the a- and b-waves was further analyzed. RESULTS: The photoreceptor inner and outer segment layer became diffusely hyperreflective in the SD-OCT images of the S334ter rats; these findings were not observed in the SD rats. This hyperreflective change corresponded to the degenerated inner and outer segments and the accumulation of the extracellular vesicles in the interphotoreceptor matrix. Quantitatively, the retinal outer sublayer and the photoreceptor sublayer in the S334ter rats became progressively thinner in comparison to those in the SD rats; the difference was statistically significant. The amplitudes of both the a- and b-waves on ERG were severely deteriorated in the S334ter rats. DISCUSSION: The SD-OCT images in the S334ter rats noninvasively provided information regarding the pathological changes in the photoreceptors and the longitudinal changes of both qualitative and quantitative changes during retinal degeneration in the S334ter rats (line 4). The pathological features of the photoreceptor inner and outer segments can be detected on SD-OCT as diffuse hyperreflective changes in the photoreceptor layer.

Characterization of photoreceptor degeneration in the rhodopsin P23H transgenic rat line 2 using optical coherence tomography.

PURPOSE: To characterize the optical coherence tomography (OCT) appearances of photoreceptor degeneration in the rhodopsin P23H transgenic rat (line 2) in relation to the histological, ultrastructural, and electroretinography (ERG) findings. MATERIALS AND METHODS: Homozygous rhodopsin P23H transgenic albino rats (line 2, very-slow degeneration model) were employed. Using OCT (Micron IV®; Phoenix Research Labs, Pleasanton, CA, USA), the natural course of photoreceptor degeneration was recorded from postnatal day (P) 15 to P 287. The OCT images were qualitatively observed by comparing them to histological and ultrastructural findings at P 62 and P 169. In addition, each retinal layer was quantitatively analyzed longitudinally during degeneration, compared it to that observed in wild type Sprague-Dawley (SD) rats. The relationships between the ERG (full-field combined rod-cone response, 3.0 cds/m2 stimulation) findings and OCT images were also analyzed. RESULTS: In the qualitative study, the two layers presumably corresponding to the photoreceptor inner segment ellipsoid zone (EZ) and interdigitation zone (IZ) were identified in the P23H rat until PN day 32. However, the photoreceptor inner and outer segment (IS/OS) layer became diffusely hyperreflective on OCT after P 46, and the EZ and IZ zones could no longer be identified on OCT. In contrast, in the SD rats, the EZ and IZ were clearly distinguished until at least P 247. The ultrastructural study showed partial disarrangements of the photoreceptor outer segment discs in the P23H rats at P 62, although a light-microscopic histological study detected almost no abnormality in the outer segment. In the quantitative study, the outer retinal layer including the outer plexiform layer (OPL) and the outer nuclear layer (ONL) became significantly thinner in the P23H rats than in the SD rats after P 71. The thickness of the IS/OS layer was maintained in the P23H rats until P 130, and it became statistically thinner than in the SD rats at P 237. The longitudinal attenuation in the amplitude of the a- and b-waves of ERG was significantly correlated with the thickness of the combined OPL and ONL but not with that of the IS/OS layer. CONCLUSION: OCT showed the degenerated photoreceptor IS/OS layer in rhodopsin P23H transgenic rats (line 2) as a diffuse hyperreflective zone, even in the early stage, with the partially disarranged and destabilized OS discs recognizable by ultrastructural assessment but not by a histological study. The amplitude of the a- and b-waves mainly depends on the thickness of the OPL and ONL layer rather than the thickness of the photoreceptor IS/OS layer in P23H rats.

Optical Coherence Tomography of Retinal Degeneration in Royal College of Surgeons Rats and Its Correlation with Morphology and Electroretinography.

PURPOSE: To evaluate the correlation between optical coherence tomography (OCT) and the histological, ultrastructural and electroretinography (ERG) findings of retinal degeneration in Royal College of Surgeons (RCS-/-) rats. MATERIALS AND METHODS: Using OCT, we qualitatively and quantitatively observed the continual retinal degeneration in RCS-/- rats, from postnatal (PN) day 17 until PN day 111. These findings were compared with the corresponding histological, electron microscopic, and ERG findings. We also compared them to OCT findings in wild type RCS+/+ rats, which were used as controls. RESULTS: After PN day 17, the hyperreflective band at the apical side of the photoreceptor layer became blurred. The inner segment (IS) ellipsoid zone then became obscured, and the photoreceptor IS and outer segment (OS) layers became diffusely hyperreflective after PN day 21. These changes correlated with histological and electron microscopic findings showing extracellular lamellar material that accumulated in the photoreceptor OS layer. After PN day 26, the outer nuclear layer became significantly thinner (P < 0.01) and hyperreflective compared with that in the controls; conversely, the photoreceptor IS and OS layers, as well as the inner retinal layers, became significantly thicker (P < 0.001 and P = 0.05, respectively). The apical hyperreflective band, as well as the IS ellipsoid zone, gradually disappeared between PN day 20 and PN day 30; concurrently, the ERG a- and b-wave amplitudes deteriorated. In contrast, the thicknesses of the combined retinal pigment epithelium and choroid did not differ significantly between RCS-/- and RCS+/+ rats. CONCLUSION: Our results suggest that OCT demonstrates histologically validated photoreceptor degeneration in RCS rats, and that OCT findings partly correlate with ERG findings. We propose that OCT is a less invasive and useful method for evaluating photoreceptor degeneration in animal models of retinitis pigmentosa.