Search

To describe the clinical and molecular characteristics of patients with childhood-onset Stargardt disease (STGD).Retrospective case series.Forty-two patients who were diagnosed with STGD in childhood at a single institution between January 2001 and January

Natsuko Nakamura,1 Kaoru Fujinami,1 Yoshinobu Mizuno,2 Toru Noda,2 Kazushige Tsunoda11Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, 2Department of Ophthalmology, National Hospital Organization, National Tokyo Medical Center, Tokyo, JapanPurpose: Full-field electroretinograms (ERGs) are used to evaluate retinal function in patients with various types of hereditary and acquired retinal diseases. However, ERG recordings require relatively invasive procedures, including pupillary dilation and the use of contact lens electrodes. Thus, it would be helpful to have a simpler and noninvasive screening method. The purpose of this study was to determine whether a new, handheld, portable ERG device, RETeval™, can be used to screen patients for cone dysfunction.Patients and methods: Thirty-five eyes of 35 patients who had reduced cone responses ascertained by a conventional ERG system using contact lens electrodes were studied. The causative diseases included achromatopsia, cone dystrophy, cone-rod dystrophy, retinitis pigmentosa, choroidal dystrophy, autoimmune retinopathy, and Stargardt disease. The flicker ERGs were recorded with the RETeval™ under undilated conditions with skin electrodes (stimulus strength, 3.0 cd·s/m2; frequency, 28.3 Hz), and the responses were compared to that of 50 healthy eyes. The amplitudes and implicit times of the fundamental component of the flicker ERGs were analyzed in three age groups: Group A, ≤20 years; Group B, 21–40 years; and Group C, ≥41 years.Results: In all of the age groups, the amplitudes of the ERGs were significantly smaller and the implicit times significantly longer in patients with cone dysfunction than in the control eyes. All but one of the patients had flicker amplitudes lower than the mean −2.0 standard deviation of control eyes.Conclusion: The RETeval™ has a potential of being used to screen for cone dysfunction. The entire examination takes

Yuko Nishikawa,1–3,* Kaoru Fujinami,1,2,4,5,* Ken Watanabe,1,2 Toru Noda,1,2 Kazushige Tsunoda,1,2 Kunihiko Akiyama1,2 1Department of Ophthalmology, National Hospital Organization, Tokyo Medical Center, Tokyo, Japan; 2Laboratory of Visual Physiology, National Institute of Sensory Organs, National Tokyo Medical Center, Tokyo, Japan; 3Department of Ophthalmology, Osaka Medical College, Takatsuki, Osaka, Japan; 4Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan; 5UCL Institute of Ophthalmology, London, UK*These authors contributed equally to this workAbstract: We describe focal choroidal excavation (FCE) in a case of Vogt–Koyanagi–Harada (VKH) disease and compare the findings with different chorioretinal conditions. A 55-year-old man was diagnosed with VKH based on panuveitis and exudative retinal detachments. Spectral-domain optical coherence tomography demonstrated a dome-shaped protrusion with a nonconforming pattern at the fovea, which had been detected as a conforming pattern 1 year before the onset. The FCE pattern returned into a conforming pattern following corticosteroid therapy. These findings suggest that the natively existent FCE could be affected by pathophysiological changes of VKH as well as other chorioretinal conditions.Keywords: choroidal excavation, focal choroidal excavation, Vogt–Koyanagi–Harada disease, optical coherence tomography

Hiroyuki Sakuramoto,1 Kazuki Kuniyoshi,1 Kazushige Tsunoda,2 Masakazu Akahori,2 Takeshi Iwata,2 Yoshikazu Shimomura1 1Department of Ophthalmology, Kinki University Faculty of Medicine, Osaka-Sayama City, Osaka, Japan; 2National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan Background: We report our findings in two siblings with late-onset cone–rod dystrophy (CRD) with no visible macular degeneration. Cases and methods: Case 1 was an 82-year-old man who first noticed a decrease in vision and color blindness in his early seventies. His mother and younger sister also had visual disturbances. His decimal visual acuity was 0.3 in the right eye and 0.2 in the left eye. Ophthalmoscopy showed normal fundi, and fluorescein angiography was also normal in both eyes. The photopic single flash and flicker eletroretinograms (ERGs) were severely attenuated and the scotopic ERGs were slightly reduced in both eyes. Case 2 was the 80-year-old younger sister of Case 1. She first noticed a decline in vision and photophobia in both eyes in her early seventies. Her decimal visual acuity was 0.4 in the right eye and 0.2 in the left eye. Ophthalmoscopy showed mottling of the retinal pigment epithelium in the midperiphery with no visible macular degeneration. The photopic single flash and flicker ERGs were severely attenuated, and the scotopic ERGs were slightly reduced in both eyes. Conclusion: These siblings are the oldest reported cases of CRD with no visible macular degeneration. Thus, CRD should be considered in patients with reduced visual acuity, color blindness, and photophobia even if they are older than 70 years. Keywords: cone–rod dystrophy, peripheral cone dystrophy, occult macular dystrophy, late onset, macular degeneration, negative ERG

Yuzhu Chai1, Hiroko Yamazaki1, Kaoru Fujinami2, Kazushige Tsunoda2, Shuichi Yamamoto31Department of Ophthalmology, Kohnodai Hospital, National Center for Global Health and Medicine, Chiba, Japan; 2National Institute of Sensory Organs, Tokyo, Japan; 3Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Chiba, JapanAbstract: Electrophysiological and morphological findings were studied in a case of acute zonal occult outer retinopathy (AZOOR) showing abnormal pattern visual evoked potentials (VEPs) at the onset and significant functional recovery in the natural course. A 21-year-old woman presented with acute onset of photopsia and a large scotoma in the right eye of 2 weeks duration. Her visual acuity was 20/20 in both eyes with no ophthalmoscopic and fluorescein angiographic abnormalities. However, a relative afferent pupillary defect and an enlarged blind spot were found in the right eye. The pattern VEPs were severely reduced when the right eye was stimulated. The amplitudes of both rod and cone full-field electroretinographics (ERGs) were reduced in the right eye. The amplitudes of the multifocal ERGs were reduced in the area of the enlarged blind spot. Irregularities in the inner segment/outer segment (IS/OS) line of the photoreceptors were observed over the nasal fovea by optical coherence tomography (OCT). The patient was followed without treatment. The enlarged blind spot disappeared in 3 months after the onset. At 5 months, reappearance of the IS/OS line was detected by OCT. At 6 months, the P100 recovered to normal values. At 1 year, the reduced full-field ERGs were almost normal size and the multifocal ERGs in the area corresponding to the enlarged blind spot were also improved. ERG findings are crucial for differentiating AZOOR from retrobulbar neuritis, especially in patients with abnormal pattern VEPs. The pattern VEPs, full-field ERGs, multifocal ERGs, and OCT images can be abnormal in the early phase of AZOOR, but they can all improve during the natural course.Keywords: AZOOR, pattern VEP, full-field ERG, multifocal ERG, OCT

A description of the high strength and high-RRR aluminum-stabilized superconductor for the ATLAS thin solenoid is provided.

Recent results of high-enthalpy extraction experiments with closed-cycle MHD disk generators are described. Power generation experiments were carried out with two types of facility: the shock tube facility with the Disk-IV generator and the FUJI-1 blow-down facility. In the shock tube experiments, the effect of channel shape on generator performance was studied using helium seeded with cesium as working fluid. A more divergent channel shape was effective in sustaining a high Hall field throughout the channel and achieving high generator performance even under the strong MHD interaction. High-enthalpy extraction of 27.3 percent was achieved. Furthermore, these experimental results agree well with the results of one-dimensional calculations. In the FUJI-1 blow-down experiments, the effect of stagnation gas pressure on performance was studied with a working gas of seeded argon. The highest enthalpy extraction ratio of 15.7 percent was achieved with the lower stagnation pressure of 0.46 MPa, whereas the largest output power of 516.7 kW and power density of 70 MW/[m.sup.3] were extracted with the nominal stagnation pressure of 0.6 MPa. This suggested the possibility of a part-load operation without significant degradation of generator performance by reducing stagnation pressure.