Paradoxic pupillary constriction in a patient with congenital stationary night blindness

Paradoxic pupillary constriction to an "off-step" of light was studied in a 35-year-old woman with congenital stationary night blindness. ERG was of the Schubert-Bornschein type (scotopic B-wave absent); fundi were normal for a high myope. Paradoxic constrictions were larger in response to full field and peripheral off-steps from low photopic levels than from higher photopic levels. The patient's "on response" was smaller in magnitude and slower in both latency and dynamics than the on-response of normal subjects. Pupillary hippus was larger in magnitude and more peaked in the patient than in normal subjects. Steady-state (tonic) pupil size increased paradoxically with increased light level over the range 1-2 log fL.     

Essential night blindness with cone monochromasy

A young patient with reduced vision complained of night blindness and color blindness. Clinical examination data and retinal densitometry were consistent with essential night blindness. Spectral sensitivity and color vision testing revealed cone monochromasy.This study was supported in part by USPHS NIH Research Grants EY 00901 and EY 01765, and by a grant from ZWO, the Dutch Organization for the Advancement of Pure Research     

Paraneoplastic night blindness with malignant melanoma

A 69-year-old hyperopic man developed acute night blindness and hallucinations of shimmering lights three years after resection of a cutaneous malignant melanoma. There were no metastatic ocular lesions and he had received no medications. His electroretinogram showed abnormalities comparable to those of patients with congenital stationary night blindness with myopia. Metastatic melanoma was recognized several months later. His electroretinographic responses were also identical to those ascribed to vincristine therapy in a previously described patient with malignant melanoma. Our findings showed that acquired night blindness, apparently resulting from interruption of intraretinal rod signal transmission, can be a paraneoplastic effect of a malignant melanoma.     

Flash full-field electroretinography in diseases with night blindness

PURPOSE: The aim of this study is to present similarities and differences of electroretinograms in early stages of retinal diseases with nyctalopia. MATERIAL AND METHODS: Flash full-field electroretinography was done according to ISCEV standards and also with chromatic stimulations in patients with nyctalopia, who were diagnosed as various forms of congenital stationary night blindness and various types of retinitis pigmentosa, choroideremia, gyrate atrophy and also in patients with nyctalopia, because of unknown reason. ERG results were compared with normal values and with each other. RESULTS: In diseases with nyctalopia the function of peripheral retina is markedly abnormal and scotopic ERG is significantly reduced or even absent. In retinitis pigmentosa a-wave is small or absent especially scotopic but photopic ERG is also abnormal. Well preserved a-wave distinguished ERG of patients with stationary night blindness from the other progressive diseases of retina or choroid. CONCLUSIONS: In patients with nyctalopia using ERG is possible to obtain which retinal elements do not work but it is only start point to following diagnostic examinations, to make proper final diagnosis.     

Congenital stationary night blindness with myopia: a clinicopathologic study

The left eye of a 77 year old male patient was enucleated because of absolute glaucoma. This eye showed subnormal electroretinogram (ERG) and oscillatory potentials preoperatively, but the other eye showed Schubert-Bornschein type ERG and monophasic dark adaptation curve. Light and electron microscopic studies of the left eye showed a normal arrangement of discs of rod outer segments, normal synaptic ends of the photoreceptors, and complete loss of ganglion cells. From the subnormal ERG in the left eye we assumed it was originally Schubert-Bornschein type ERG but inverted to subnormal type ERG following the loss of inhibitory mechanisms. Thus we propose that the cause of night blindness in congenital stationary cases with Schubert-Bornschein type ERG may be related to the mechanisms inhibitory to cells of the bipolar layer.     

Xerophthalmia and acquired night blindness in a patient with a history of gastrointestinal neoplasia and normal serum vitamin A levels

A 69-year-old male patient presented to our department with a 3-month history of nyctalopia. Reviewing of his general health revealed a history of gastrointestinal tumor treated with a modified WHIPPLE operation. Ocular findings at presentation included mild xerophthalmic features and nonspecific pigmentary retinal changes. A standard full-field electroretinogram (ERG) was obtained that showed normal photopic function and extinguished scotopic function. The ocular symptoms, the history and the ERG findings suggested vitamin A deficiency as a possible cause for his complaints. Serum vitamin A levels were subsequently requested, but the results were within normal limits. Despite the normal serum vitamin A levels, the patient was instructed to commence treatment with high doses of oral vitamin A supplements. One month after the onset of the treatment, the patient reported that his visual function has significantly improved, while repeat ERG testing revealed that scotopic function has improved to normal levels. This case highlights that in patients with acquired night blindness due to vitamin A deficiency, the ERG responses possibly represent a more sensitive marker compared to the serum levels of vitamin A.     

Functional abnormalities in vincristine-induced night blindness

Various noninvasive test procedures were used to evaluate retinal function in a patient who had become night blind following vincristine chemotherapy. The results obtained were strikingly similar to those reported previously in subjects with recessively inherited stationary night blindness; the dark-adaptation curve was monophasic (ie, no evidence of a scotopic branch), rhodopsin kinetics were entirely normal, and spectral threshold data revealed the presence of residual rod-mediated vision. Also like the heritable condition, the b-wave of the ERG was depressed grossly despite normal a-wave potentials. These findings, and the fact that vincristine is known to disrupt the structural integrity of neuronal microtubules, suggest that the drug-induced defect involves the process of synaptic transmission between the photoreceptors and their second-order neurons.     

先天性静止性夜盲的多焦ERG特征

目的探讨先天性静止性夜盲眼在不同离心度多焦视网膜电图(mERG)振幅和潜伏值改变与先天性静止性夜盲(CSNB)的关系.方法应用mERG技术对CSNB患者8人14眼进行检测,随机选用视力1.0以上、年龄匹配的正常人14眼作为对照.MERG检测选用103个六角形刺激成分,采用刺激频率75 Hz的短m序列对后极部30°视网膜进行刺激和同步记录,分析6个不同离心环一级反应的b波反应密度和a,b波潜伏值以及受刺激视网膜提取的b波反应密度和及各波潜伏值和.结果从CSNB提取的mERG反应的1环及2环的b波反应密度值与对照组相比轻度下降,但无统计学差异(P＞0.05),而3～6环各环b波反应密度值与对照组相比明显下降(P＜0.01).此外,患病组从1～6环各环提取的mERG反应的a,b波潜伏值较正常对照组严重下降(P＜0.01),且异常程度较b波反应密度值更严重.患病组后极部30°范围视网膜b波反应密度和及a,b波潜伏值和较对照组明显下降.结论MERG能客观评价CSNB局部视网膜功能损害程度,mERG潜伏值的延长较其振幅改变和心理物理学的视野检查更能揭示CSNB功能改变的特征.     

Diagnostic clinical findings of a new syndrome with night blindness, maculopathy, and enhanced S cone sensitivity

We studied eight patients who had night blindness, maculopathy (often cystoid), degenerative changes in the region of the vascular arcades, relatively mild visual field loss, and an unusual but characteristic electroretinogram. The dark-adapted electroretinogram showed no response to low-intensity stimuli that normally activate the rods, but large, slow responses to high-intensity stimuli. These large, slow waveforms persisted without change under light adaptation, and showed a striking mismatch to photopically balanced short and long wavelength stimuli (with sensitivity much greater to short than long wave-lengths). Since there is evidence from other studies that the electroretinogram and psychophysical responses represent hypersensitivity of short wavelength-sensitive (S or blue) cones, we propose that this disorder be called the enhanced S cone syndrome. There can be different degrees of severity in this syndrome, and progression appears to be slow.     

Rayleigh match in congenital stationary night blindness

Rayleigh matches performed by 13 patients with Schubert-Bornschein type congenital stationary night blindness with normal color vision, revealed that they use consistently slightly more red light primary in order to achieve a brighter yellow match than a control group with normal color vision and visual acuity. The matching differences between the two groups were statistically significant.     

Recurrent anterior uveitis associated with streptococcal pharyngitis in a patient with a history of poststreptococcal syndrome

PURPOSE: To provide additional evidence that anterior uveitis can be a manifestation of poststreptococcal syndrome. METHOD: A case report providing follow-up information on a previously described patient. RESULTS: An adolescent girl in whom anterior uveitis was the only manifestation of poststreptococcal syndrome subsequently developed recurrent anterior uveitis after another episode of streptococcal pharyngitis. CONCLUSION: Anterior uveitis can recur in a manner similar to other manifestations of poststreptococcal syndrome after reinfection with group A streptococci.