Novel biallelic loss-of-function KCNV2 variants in cone dystrophy with supernormal rod responses.

PURPOSE: To report clinical and genetic features including long-term full-field electroretinography (FF-ERG) findings of a patient with cone dystrophy with supernormal rod responses (CDSRR). METHODS: Ophthalmological medical records including FF-ERG were retrospectively reviewed. Genetic analysis using whole-exome sequencing (WES) was performed. Identified KCNV2 variants were confirmed by Sanger sequencing. RESULTS: A 30-year-old female patient was referred to our hospital for assessment of decreased vision from childhood. Funduscopy showed macular atrophy in both eyes. FF-ERG showed decreased amplitudes and delayed peak time of b-waves for dark-adapted (DA) 0.01 ERG, increased b/a-wave ratio with a slightly diminished a-wave for DA 3.0 and DA 25.7 ERG, residual a-waves and almost extinguished b-waves for light-adapted (LA) 3.0 ERG, and extremely diminished amplitudes in LA 30-Hz flicker responses. At 45 years of age, funduscopy showed progressive macular atrophy, whereas the responses for her FF-ERG remained unchanged compared to those observed at 30 years of age. WES identified the compound heterozygous KCNV2 variants (p.W67X and p.D174GfsX198) in the patient. These variants have previously been unreported as pathogenic variants. Each parent had one of the variants. Subsequently, the patient was finally diagnosed with CDSRR with the novel compound heterozygous KCNV2 variants. CONCLUSIONS: Biallelic loss-of-function KCNV2 variants (p.W67X and p.D174GfsX198) were identified as the cause of CDSRR. Long-term FF-ERG findings demonstrated there were no ERG changes during 15 years of observation, indicating that there was no evidence of progressive peripheral retinal dysfunction, in spite of worsening macular atrophy.

Improved Photoreceptor Function in Male Acute Zonal Occult Outer Retinopathy.

PURPOSE: To describe male acute zonal occult outer retinopathy (AZOOR) patients with improvement of photoreceptor structure and visual function. CASE SERIES: Medical records for eight eyes in seven patients (mean age, 36.9 years; range, 22 to 57 years) with AZOOR were reviewed retrospectively. Of the seven patients, four were treated with high-dose methylprednisolone therapy and three were not treated. All patients presented with photopsias and severe vision loss in the affected eyes. Visual acuity ranged from 0.2 to 1.5 on a Snellen decimal scale and Humphrey visual field testing showed blind spot enlargement or ring scotomas. Fundus and angiographic examinations found no specific abnormalities, leading to a diagnosis of AZOOR. Spectral domain optical coherence tomography showed attenuation of the photoreceptor inner segment ellipsoid zone. Multifocal electroretinography demonstrated that there were decreased responses at the site of the spectral domain optical coherence tomography abnormalities and corresponding visual field loss. Three patients had a spontaneous resolution with restoration of photoreceptor structure and visual function, and four patients had a visual improvement with restoration of photoreceptor structure and visual function after steroid pulse therapy. CONCLUSIONS: These results suggest that male AZOOR patients may have a tendency of visual improvement both with and without treatment.

Electroretinography in streptozotocin diabetic rats following acute intraocular pressure elevation.

BACKGROUND: We consider whether pre-existing streptozotocin induced hyperglycemia in rats affects the ability of the eye to cope with a single episode of acute intraocular pressure (IOP) elevation. METHODS: Electroretinogram (ERG) responses were measured (-6.08 to 1.92 log cd.s.m(-2)) in anaesthetized (60:5 mg/kg ketamine:xylazine) dark-adapted (>12 h) adult Sprague-Dawley rats 1 week after a single acute IOP elevation to 70 mmHg for 60 min. This was undertaken in rats treated 11 weeks earlier with streptozotocin (STZ, n = 12, 50 mg/kg at 6 weeks of age) or citrate buffer (n = 12). ERG responses were analyzed to derive an index of photoreceptor (a-wave), ON-bipolar (b-wave), amacrine (oscillatory potentials) and inner retinal (positive scotopic threshold response, pSTR) function. RESULTS: One week following acute IOP elevation there was a significant reduction of the ganglion cell pSTR (-35 ± 11 %, P = 0.0161) in STZ-injected animals. In contrast the pSTR in citrate-injected animals was not significant changed (+16 ± 14 %). The negative component of the STR was unaffected by IOP elevation in either citrate or STZ-treated groups. Photoreceptoral (a-wave, citrate-control +4 ± 3 %, STZ +4 ± 5 %) and ON-bipolar cell (b-wave, control +4 ± 3 %, STZ +4 ± 5 %) mediated responses were not significantly affected by IOP elevation in either citrate- or STZ-injected rats. Finally, oscillatory potentials (citrate-control +8 ± 23 %, STZ +1 ± 17 %) were not reduced 1 week after IOP challenge. CONCLUSIONS: The ganglion cell dominated pSTR was reduced following a single episode of IOP elevation in STZ diabetic, but not control rats. These data indicate that hyperglycemia renders the inner retina more susceptible to IOP elevation.

Resolution of acute photoreceptor damage as revealed by serial SD-OCT.

PURPOSE: To describe findings in spectral-domain optical coherence tomography (SD-OCT) for four patients with acute foveal photoreceptor damage. CASE REPORT: Four patients with acute foveal photoreceptor damage were evaluated by color photography and SD-OCT during follow-up. All four cases were Japanese patients with high myopia. Three were women aged 28, 29, and 46 years and one was a boy aged 17 years. The follow-up ranged from 2 weeks to 3 months. On presentation, four eyes had orange-yellow foveal granularity with visual acuities that varied from 1.2 to 0.5. Spectral-domain optical coherence tomography revealed a disrupted photoreceptor layer. All patients achieved spontaneous resolution without treatment within a few months. Of the four eyes, only one had recurrence of the disease. CONCLUSIONS: Lesions exhibiting orange-yellow foveal granularity characteristic of these four cases corresponded to hyperreflective localized photoreceptor lesions on SD-OCT. Spectral-domain optical coherence tomography was useful for detecting an acute disruption and a resolution of the photoreceptor layer in the fovea.

[Stickler syndrome with rhegmatogenous retinal detachment].

BACKGROUND: Stickler syndrome is an autosomal dominant disease characterized by various disorders of the eyes and the connective tissues throughout the body. It can arise from a mutation in the collagen associated gene. We present a case of Stickler syndrome with rhegmatogenous retinal detachment. CASE: A 10-years-old boy was referred to us with rhegmatogenous retinal detachment of the right eye. His family history included eye disease and a cleft palate. He had high myopia, vitreous liquefaction and lattice degeneration in the both eye. He also had a cleft palate and a broad nasal bridge. His condition was diagnosed as Stickler syndrome. We performed vitrectomy, scleral buckling and encircling, and silicone oil injection in the right eye. We also did a reattachment of the retina in the right eye. CONCLUSIONS: Pediatric retinal detachment may indicate the presence of Stickler syndrome and a complete examination of the eye as well as a full family history must be obtained in such cases.

Mutagenicity and PAH contents of soil in forests or planted areas in Japan.

We investigated the behavior of mutagenic substances in the soil of forests or planted areas. Mutagenicity and concentration was examined for 16 types of PAHs in soil samples collected at a depth of 1 m in 10 forests in Iwate, Ibaraki, Tokyo, Kanagawa, Yamanashi and Shizuoka prefectures in Japan. Mutagenicity and PAHs were detected mostly in soil from the surface to a depth of 30 cm when strains TA100, TA98 and YG1024 were used. In addition, a significant correlation was not found between the concentration of BaP, and specific mutagenic activity (TA98 without S9mix, r = 0.285).

Combination Surgery With Transcorneal Microincision Vitrectomy Surgery and Intrascleral Intraocular Lens Fixation for Spontaneous Intraocular Lens Luxation.

To present a combination technique for two cases of in-the-bag intraocular lens (IOL) luxation into the vitreous cavity. Vitrectomy was performed via a cornea microincision vitrectomy system, and the luxated IOL was fixed into the sclera. IOL fixation is simple from no trocar cannulas and less disrupted conjunctiva. Postoperative corneal endothelial cell density in Case 1 and Case 2 were reduced by -2.1% and -5.1%, respectively. Postoperative frequency of hexagon was decreased in Case 1 but maintained in Case 2. The authors concluded that combination surgery has distinct benefits for IOL luxation; however, long-term corneal changes need to be further assessed. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:267-271.].

Efficacy of Intravitreal Triamcinolone Acetonide for Diabetic Macular Edema After Vitrectomy.

PURPOSE: To compare the efficacy of intravitreal injection of triamcinolone acetonide (IVTA) for diabetic macular edema (DME) in vitrectomized eyes with DME without vitrectomy eyes. METHODS: This retrospective comparative study evaluated the efficacy of IVTA treatment of DME in 26 consecutive eyes (23 patients). Changes in mean best-corrected visual acuity (VA) and mean central retinal thickness (CRT) were retrospectively evaluated before IVTA and during the 6-month period after IVTA. RESULTS: Subjects were divided into 2 groups: 13 consecutive eyes (11 patients) with proliferative diabetic retinopathy or DME that underwent vitrectomy (vitrectomized group), and 13 consecutive eyes (12 patients) with DME who received IVTA, but did not undergo vitrectomy (nonvitrectomized group). In the vitrectomized group, there was a significantly decreased CRT for up to 4 months as compared to the thicknesses before IVTA. In the nonvitrectomized group, there was a significantly decreased CRT for up to 5 months after IVTA. In both groups, there was significant improvement in the VA for up to 4 months after IVTA. CONCLUSION: IVTA may represent a valid treatment option for DME, even in vitrectomized eyes.

Evaluation of S-cone sensitivity in reattached macula following macula-off retinal detachment surgery.

PURPOSE: To investigate the recovery of short-wavelength sensitivity in patients who had undergone successful reattachment of a rhegmatogenous retinal detachment with macular involvement. METHODS: Postoperative assessment of the visual acuity and the visual fields by standard achromatic automated perimetry (SAP), and short-wavelength automated perimetry (SWAP, Humphrey visual field analyzer; macula test pattern) was performed on 12 patients after the macula was reattached. The follow-up period was up to 12 months. RESULTS: The visual acuity and SAP sensitivity recovered rapidly after reattachment, with further moderate improvements up to 6 months after reattachment. The improvements stabilized by 9 to 12 months. The SWAP sensitivities improved more slowly than the visual acuity or SAP sensitivities, but they continued to improve even when visual acuity or SAP sensitivities had stabilized. CONCLUSION: We conclude that measurement of the sensitivities of the short-wavelength-sensitive cones (S-cones) with SWAP may be a sensitive method to evaluate the visual recovery of the reattached macula following macula-off retinal detachment.

Measurement of polynuclear aromatic hydrocarbons in canine lung after alkaline decomposition.

An alkaline decomposition method employing a KOH/alcohol solution was studied, and polynuclear aromatic hydrocarbons (PAHs) contained in particles remaining in canine lung were measured. As a result, BaA, BkF, BaP, and BghiP were found. By this method, PAHs extracted from the lungs of 32 dogs were 13.0-166.0 ng (mean, 63.0 ng) for BaA, 6.6-90.2 ng (mean, 27.4 ng) for BkF, 9.8-167.4 ng (mean 47.2 ng) for BaP, and 10.8-206.0 ng (mean, 61.8 ng) for BghiP. The results showed no correlation between the age and the concentration of PAHs in the lung, but some correlation was found between the age and the lung weight (p<0.01). There were significant correlations among the concentrations of the compounds in the lung (p<0.01). These results suggest that dogs, like humans, are affected by automobile exhaust and other common generation sources of such substances.

[Bilateral retinal detachment after laser in situ keratomileusis].

BACKGROUND: We report a case of bilateral retinal detachment after laser in situ keratomileusis(LASIK). CASE: A 49-year-old man received multiple laser photocoagulation for retinal lattice degeneration in both eyes and retinal tears in the left eye. He underwent bilateral LASIK in another country about 6 months after the laser photocoagulation. After the LASIK his eyes showed bilateral retinal detachment, 2 weeks later in the right eye and 5 months later in the left eye. We had to perform retinal detachment surgery four times, scleral buckling, vitrectomy, silicone oil tamponade, and removal of the silicone oil for the right eye, and one scleral buckling procedure for the left eye to achieve retinal attachment. Soon after each retinal surgery, we recognized diffuse flap edema and interface haze, three times in the right cornea and one time in the left, although this corneal flap edema subsided without any sequel. CONCLUSION: In this case, laser photocoagulation had been done several times to prevent retinal detachment in both eyes. However, retinal detachment occurred 2 weeks after LASIK in the right eye, and therefore, the LASIK procedure was considered to be the main factor influencing the development of the retinal detachment. The left eye showed retinal detachment 5 months after LASIK and we thought it possible that this retinal detachment occurred as a natural consequence of myopia. We believe it is important to hava a thorough funduscopic examination done before LASIK and it is necessary to pay attention to corneal edema and interface haze after retinal detachment surgery for post-LASIK patients.

Use of DNA microarray analysis in diagnosis of bacterial and fungal endophthalmitis.

BACKGROUND: To examine the utility of DNA microarray analysis for identifying causative microorganisms in endophthalmitis. METHODS: Thirteen samples of vitreous fluid (VF) were obtained from 13 patients during vitrectomy. Vitreous fluids from three patients with suspected endophthalmitis and ten controls without infection were subjected to testing for the presence of bacteria and fungi in culture tests, polymerase chain reaction (PCR) analysis, and DNA microarray analysis. RESULTS: No control sample was positive for bacteria or fungi in the culture test, PCR, or microarray analysis. Specimens from two patients (Cases 1 and 2) with suspected endophthalmitis were positive for bacteria in PCR, and a specimen from one patient (Case 3) was positive for fungi in PCR. Klebsiella pneumonia (Case 1), Streptococcus agalactiae (Case 2), and Candida parapsilosis (Case 3) in the PCR-positive specimens were identified by DNA microarray analysis within 24 hours. Culture results were also positive for K. pneumonia in Case 1, S. agalactiae in Case 2, and C. parapsilosis in Case 3, but required 3 to 4 days to obtain. CONCLUSIONS: Microarray analysis is complementary to routine cultures for identifying causative microorganisms and is likely to be a useful tool in patients with suspected endophthalmitis who require rapid diagnosis and early antibiotic treatment.

Early inner retinal dysfunction in streptozotocin-induced diabetic rats.

PURPOSE: Diabetes is known to alter retinal function, as measured with the electroretinogram (ERG), which shows a propensity toward inner retinal oscillatory potential (OPs) abnormalities. However, the effect that diabetes has on other ganglion cell-related responses is not known. This study was a systematic evaluation of streptozotocin (STZ) diabetes-related ERG changes in rats for the first 11 weeks after diabetogenesis. METHODS: Thirty Sprague-Dawley rats were randomly assigned to treated (50 mg/kg STZ (n = 16) and control groups (1 mL/kg citrate buffer, n = 14) at 6 weeks of age. Two control animals and four STZ animals were excluded because of blood glucose criteria or systemic complications. Diabetic animals were given daily SC injections of 1 to 2 units of long-acting insulin. ERGs were measured at 4, 8, and 11 weeks after treatment. The a-wave was used as an index of outer retinal function, whereas the b-wave, OPs, and the scotopic threshold response (STR) were used as indices of inner retinal function. RESULTS: Photoreceptoral (a-wave) and bipolar cell (b-wave) responses were not significantly reduced by STZ treatment. OPs were significantly reduced by 8 weeks (-25% +/- 7%, P < 0.05). The most severely affected component was the ganglion cell-dominated positive STR, which was significantly decreased from the first time point (-51% +/- 11% at 4 weeks, P < 0.05), but the negative component was unaffected over the 11-week period. CONCLUSIONS: The ganglion cell dominated pSTR showed large losses in STZ treated rats.