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AIM: To investigate the changes of visual function and multifocal visual evoked potential in children with strabismus after intermittent exotropia operation.METHODS: Totally 91 children with intermittent exotropia from January 2014 to December 2017 were enrolled in the study. All children were treated with surgery. The changes of visual function before and after operation were observed, and the level of multifocal visual evoked potential before and after operation were detected. RESULTS: The total effective rate was 88% at one week after operation, 86% at 6mo after operation, the mean preoperative strabismus was-38.12△, and the mean postoperative strabismus was-5.8△. At 6mo after operation, the number of children with simultaneous vision, fusion and distant stereopsis decreased significantly as compared with that before operation(PPPCONCLUSION: Intermittent exotropia operation can effectively improve the visual function of children and promote the recovery of eye position in children, and the level of multifocal visual evoked potential in children after operation is also improved to some extent. The clinical effect is outstanding, and it is worth popularizing and applying.

Background: Visual field defects are a common and disabling consequence of stroke and a negative prognostic factor of patient's quality of life. They result from lesions in different parts of the visual system, most commonly the visual cortex and optic radiation. An important pathophysiological mechanism is transsynaptic retrograde degeneration (TRD).Methods: In a case series 21 patients with posterior cerebral artery (PCA) territory infarctions were analyzed by spectral-domain optical coherence tomography (SD-OCT) and multifocal visual evoked potentials (mfVEPs) cross-sectionally and longitudinally for up to 6 months. In OCT, symptomatic affected nasal and temporal sectors and corresponding visual fields in mfVEPs were compared to the contralateral side.Results: SD-OCT revealed a significant reduction (−2.92 ±2.53 μm, mean ± SD) of the symptomatic nasal macular retinal nerve fiber layer (RNFL) thickness and of the symptomatic temporal peripapillary RNFL after 6 months compared to baseline whereas the symptomatic temporal macular quadrant already showed a significantly thinner RNFL at baseline. The mfVEP first peak latency at baseline was significantly different (nasal visual field +11.69 ±11.17 ms, mean ± SD; temporal visual field +16.63 ±7.97 ms, mean ± SD) on the symptomatic compared to the asymptomatic field. The nasal visual fields partly recovered in amplitude and first peak latency of mfVEPs over the following 6 months compared to baseline.Conclusion: The dynamics of OCT and mfVEP outcomes for degeneration and recovery after PCA infarction differ between the nasal and temporal retinal sector. We postulate that retinal sectors may differ in their temporal pattern of TRD over time after retrogeniculate cerebral infarction.

Background: Visual field defects are a common and disabling consequence of stroke and a negative prognostic factor of patient's quality of life. They result from lesions in different parts of the visual system, most commonly the visual cortex and optic radiation. An important pathophysiological mechanism is transsynaptic retrograde degeneration (TRD). Methods: In a case series 21 patients with posterior cerebral artery (PCA) territory infarctions were analyzed by spectral-domain optical coherence tomography (SD-OCT) and multifocal visual evoked potentials (mfVEPs) cross-sectionally and longitudinally for up to 6 months. In OCT, symptomatic affected nasal and temporal sectors and corresponding visual fields in mfVEPs were compared to the contralateral side. Results: SD-OCT revealed a significant reduction (−2.92 ±2.53 μm, mean ± SD) of the symptomatic nasal macular retinal nerve fiber layer (RNFL) thickness and of the symptomatic temporal peripapillary RNFL after 6 months compared to baseline whereas the symptomatic temporal macular quadrant already showed a significantly thinner RNFL at baseline. The mfVEP first peak latency at baseline was significantly different (nasal visual field +11.69 ±11.17 ms, mean ± SD; temporal visual field +16.63 ±7.97 ms, mean ± SD) on the symptomatic compared to the asymptomatic field. The nasal visual fields partly recovered in amplitude and first peak latency of mfVEPs over the following 6 months compared to baseline. Conclusion: The dynamics of OCT and mfVEP outcomes for degeneration and recovery after PCA infarction differ between the nasal and temporal retinal sector. We postulate that retinal sectors may differ in their temporal pattern of TRD over time after retrogeniculate cerebral infarction. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effects of glaucomatous damage on the mfVEP parameters of patients suffering from primary open-angle glaucoma (POAG). Methods: Fifteen healthy subjects and 15 patients with unilateral POAG participated in this study. In addition, routine ophthalmological examinations including visual acuity, anterior segment examination, posterior segment examination, intraocular pressure, mfVEP with electrophysiological system, RETI-port/Scan 21, and visual field test with automated Humphrey ZEISS HFA II 750i Perimeter were also performed. Results: The results show that there was a strong correlation between the ∆MDs and the number of abnormal points with the ∆amplitudes more than 256 nV, in patients (n = 15, r = 0.802, p < 0.05), but no correlations were found between the mean sensitivity differences (ΔPSDs) and mfVEP parameters. Conclusions: Comparing the monocular mfVEP responses from both eyes is an appropriate method to detect unilateral damage. Achievement of more development and making the mfVEP test more functional can be a solution for early diagnosis in most of the eye diseases. [ABSTRACT FROM AUTHOR]

Background: Sellar region tumor growth represents an important cause of visual loss due to mechanical compression of the optic nerve apparatus. Many investigations have used non-invasive tools to evaluate the visual field consequences of this damage, and good associations have been reported between psychophysical and electrophysiological perimetries. Few reports have considered the tumor size as a predictor of visual field loss. Aims: In the present study, we evaluated the association between the visual perimetry measured by Humphrey visual field analyzer and multifocal visual evoked cortical potential (mfVECP) and the tumor size. Methods: Our sample was composed of 14 patients diagnosed with sellar tumors by magnetic resonance imaging. We accounted the number of sectors with negative visual responses for both methods. A simple logistic regression analysis was used to evaluate the association between the tumor dimensions and the visual field features Results: Three patients had preserved visual fields, three patients showed hemianopic defects, and eight patients had generalized visual field losses at both evaluations. We observed that the three maximum diameters of the tumor and total tumor volume had different predictive abilities regarding the extent of visual field loss when using psychophysical and mfVECP data. The maximum craniocaudal diameter of the tumor was the better predictor of the psychophysical measurements, whereas for the mfVECP results, all tumor dimensions and volumes had similar values that predict visual field losses. Conclusion: Tumor size as a predictor of visual loss has potential to assist in the clinical intervention and to prevent the irreversible visual impairment caused by tumors of the sellar region. [ABSTRACT FROM AUTHOR]

Background: Symptomatic carotid artery disease (CAD) may cause modified blood supply to the retina possibly leading to retinal structure changes. Results of previous studies in asymptomatic CAD were heterogeneous in retinal layer changes measured by OCT. The objectives of this prospective, non-interventional study were to investigate if structural retinal changes occur in symptomatic CAD patients with macroangiopathic ischemic stroke or transient ischemic attack (TIA).Methods: We used spectral-domain optical coherence tomography (SD-OCT) to cross-sectionally and longitudinally analyze the retinal morphology of CAD patients with macroangiopathic ischemic stroke or TIA not permanently affecting the visual pathway. We employed semi-automated segmentation of macular volume scans to assess the macular retinal layers' thickness and peripapillary ring scans to determine the peripapillary retinal nerve fiber layer thickness using the contralateral eye and eyes of microangiopathic ischemic stroke patients with matched age, gender, and vascular risk factors as control. Visual function and visual field deficits were assessed by multifocal visual evoked potentials (mfVEP).Results: Neither the thickness of retinal layers measured by SD-OCT in 17 patients nor the mfVEP latency or amplitude in 10 patients differed between the symptomatic stenotic, the contralateral internal carotid artery (ICA) side and the control group of 17 microangiopathic stroke patients at baseline. Furthermore, longitudinal investigations of 10 patients revealed no significant changes of any retinal layer 4 months after ischemic stroke or TIA.Conclusion: In conclusion, our study revealed no evidence for an impact of symptomatic carotid artery disease on retinal structure or functional impairment of the visual pathway.

Background: Symptomatic carotid artery disease (CAD) may cause modified blood supply to the retina possibly leading to retinal structure changes. Results of previous studies in asymptomatic CAD were heterogeneous in retinal layer changes measured by OCT. The objectives of this prospective, non-interventional study were to investigate if structural retinal changes occur in symptomatic CAD patients with macroangiopathic ischemic stroke or transient ischemic attack (TIA). Methods: We used spectral-domain optical coherence tomography (SD-OCT) to cross-sectionally and longitudinally analyze the retinal morphology of CAD patients with macroangiopathic ischemic stroke or TIA not permanently affecting the visual pathway. We employed semi-automated segmentation of macular volume scans to assess the macular retinal layers' thickness and peripapillary ring scans to determine the peripapillary retinal nerve fiber layer thickness using the contralateral eye and eyes of microangiopathic ischemic stroke patients with matched age, gender, and vascular risk factors as control. Visual function and visual field deficits were assessed by multifocal visual evoked potentials (mfVEP). Results: Neither the thickness of retinal layers measured by SD-OCT in 17 patients nor the mfVEP latency or amplitude in 10 patients differed between the symptomatic stenotic, the contralateral internal carotid artery (ICA) side and the control group of 17 microangiopathic stroke patients at baseline. Furthermore, longitudinal investigations of 10 patients revealed no significant changes of any retinal layer 4 months after ischemic stroke or TIA. Conclusion: In conclusion, our study revealed no evidence for an impact of symptomatic carotid artery disease on retinal structure or functional impairment of the visual pathway. [ABSTRACT FROM AUTHOR]

Highlights • MfVEP amplitude is more highly correlated with GCIPL than RNFL thickness in ON. • GCIPL is a strong structural biomarker for optic nerve degeneration in RRMS. • MfVEP is more sensitive than OCT in detecting subclinical defects in non-ON. Abstract Objective To examine the relationship between optical coherence tomography (OCT) macular ganglion cell-inner plexiform layer thickness (GCIPLT), peripapillary retinal nerve fiber layer thickness (RNFLT) and visual function in relapsing-remitting multiple sclerosis (RRMS). Methods Cirrus OCT, VERIS 60-sector multifocal visual evoked potential (mfVEP) and Pelli-Robson contrast sensitivity (CS) were obtained for 53 eyes with last optic neuritis (ON) > 6 months and 105 non-ON eyes in 90 patients. One eye (43 ON, 73 non-ON) was used for correlations when both had the same history. Global (G, 60 sectors) and central 5.6° (C, 24 sectors) mfVEP amplitude and latency were calculated as mean logSNR and median latency. Results Eyes showing abnormal mfVEP (amplitude or latency) vs OCT (GCIPLT or RNFLT) was 77% vs 69% (p = 0.33) in ON, 45% vs 22% (p < 0.0005) in non-ON. In ON and non-ON, mfVEP measures and CS correlated with GCIPLT and RNFLT (r = −0.24 to 0.78, p = 0.03–0.0001). In ON, mfVEP amplitude (C,G) correlated better with GCIPLT (r = 0.78, 0.76) than RNFLT (r = 0.43, 0.58; p < 0.001, 0.01). Conclusions MfVEP measures and CS correlated well with GCIPLT and RNFLT in ON and non-ON. MfVEP amplitudes were more highly correlated with GCIPLT than RNFLT in ON. MfVEP detected significantly more defects than OCT in non-ON. Significance GCIPLT, mfVEP and CS provide useful measures of optic nerve integrity in RRMS. [ABSTRACT FROM AUTHOR]

Context: Intracameral mydriatic solution can eliminate the disadvantages of repeated eye drop instillation regimen and provide adequate mydriasis for phacoemulsification with added advantages. Aims: Evaluating the role of intracameral irrigating solution (0.5% lignocaine + 0.001% epinephrine) in initiating and maintaining the pupillary mydriasis during phacoemulsification. Secondary aims were to observe the effect of surgical time, nucleus density and ultrasound time on mydriasis during the procedure. Settings and Design: The study is a prospective interventional case series, conducted at tertiary care institution. Materials and Methods: Thirty patients underwent phacoemulsification under topical anesthesia for visually significant cataract. Pupillary dilatation was achieved by intracameral irrigation of mydriatic solution alone. Pupillary diameter was measured serially during surgery and ultrasound time and total surgical time were noted. Statistical Analysis Used: Paired samples student-t test was done to compare means. Spearman correlation coefficient was used to study the effect of various parameters on mydriasis. Results: Thirty eyes completed the study. The pupil size increased from 2.1 mm (Range 2-3.5 mm SD ± 0.32) to 6.9 mm (Range 5-9 mm SD ± 1.02) in 30 seconds time after intracameral mydriatic solution delivery, and was 7.0 mm (Range 3.5 - 9 mm SD ± 0.20) at the end of surgery. Duration of surgery, grade of nucleus and ultrasound time had statistically insignificant effect on mydriasis. Conclusions: Intracameral solution containing 0.5% lignocaine and 0.001% epinephrine provides rapid mydriasis which is adequate for safe phacoemulsification and is unaffected by other parameters.

Background: Regular follow up and amblyopia treatment are essential for good outcomes after pediatric cataract surgery. Aim: To study the regularity of follow-up after cataract surgery in children and to gauge the causes of poor compliance to follow up. Subjects: 262 children (393 cataracts) who underwent cataract surgery in 2004-8. Materials and Methods: The children were identified and examined in their homes and a "barriers to follow-up" questionnaire completed. Demographic data collected, visual acuity estimated, and ocular examination performed. Statistical Analysis: SPSS version 19. Results: Of the 262 children, only 53 (20.6%) had been regularly following up with any hospital, 209 (79.4%) had not. A total of 150 (57.3%) were boys and the average age was 13.23 years (Std Dev 5 yrs). Poor follow up was associated with the older age group ( P < 0.001), less education of mother ( P = 0.012), father′s occupation ( P = 0.031), how much money spent on travel ( P = 0.033) and was it paid or free surgery ( P = 0.001). It was not related to gender, numbers of children in family, ordinal status of child, and social strata. Distance and cost were major barriers, as was the inability of the eye care center to communicate the importance of follow up. A prospective follow-up visit showed that 93 children needed Nd: YAG LASER capsulotomy, 5 needed low vision aids, 4 contact lens, and 162 a change of spectacles. The average visual acuity improved in 150 (38.8%) eyes >1 line with regular follow-up. Conclusion: Regular follow-up is important and improves vision; eye care practitioners need to take special efforts to ensure better follow-up.

Orbital complications due to ethmoiditis are rare in neonates. A case of orbital abscess due to acute ethmoiditis in a 28-day-old girl is presented. A Successful outcome was achieved following antimicrobial therapy alone; spontaneous drainage of the abscess occurred from the lower lid without the need for surgery. From this case report, we intend to emphasize on eyelid retraction as a sign of neonatal orbital abscess, and to review all the available literature of similar cases.

Rhodotorula mucilaginosa rarely cause keratitis in immunocompromised individuals. A 30 year old male with history of minor trauma presented with cotton wool like stromal infiltration and hypopyon in left eye. Microbiological examination of corneal scraping showed fungal hyphae and yeast cells in direct smear. Molecular identification of the organism was performed which showed 100% homology with Rhodotorula mucilaginosa. Management of these cases is difficult often necessitating surgical procedures. However further reports are necessary to understand the disease and establish a treatment protocol.

Purpose: To determine the effect of a capsular tension ring (CTR) implantation in preventing posterior capsular opacification (PCO) after cataract surgery in patients with high myopia. Materials and Methods: In this prospective single-surgeon standardized-surgical-procedure fellow-eye comparison trial, 34 patients with high myopia had phacoemulsification surgery. Although one eye received an acrylic intraocular lens (IOL) and CTR, other eye received only an IOL as control. PCO, within the capsulorhexis overlap, was documented by standardized digital retroillumination images at least 2 years post-operatively, and the percentage area of PCO was scored (scale 0%-100%) using the POCOman software system. The PCO score and the incidence of neodymium-doped yttrium aluminum garnet (Nd: YAG) capsulotomy of groups, and correlations between PCO score and presence of CTR, age, phaco time, refraction, and axial length (AL) were determined. Results: The mean time interval from surgery to PCO measurement was 43.4 ± 11.2 months for the eyes with a CTR and 43.1 ± 11.6 months for the controls (P = 0.91). The PCO score of the eyes with a CTR was significantly lower than in the controls (5.9 ± 4.3 vs. 22.3 ± 12.2, respectively; P < 0.001). There were statistically insignificant correlations between PCO score and pre-operative refraction (r = 0.02; P = 0.90), AL (r = 0.03; P = 0.80), phaco time (r = 0.11; P = 0.53), and patient′s age (r = 0.23; P = 0.55). No patient with a CTR had a Nd: YAG laser capsulotomy, but it was six in controls (P = 0.025). Conclusions: CTR implantation seems to be effective in reducing the PCO and Nd: YAG laser capsulotomy rates in high myopic eyes.

Pellucid marginal degeneration (PMD) is an uncommon cause of inferior peripheral corneal thinning disorder, characterized by irregular astigmatism. We analyzed a case of bilateral PMD patient and treated one eye with corneal collagen cross-linking (CXL) therapy. Corneal topography was characteristic for PMD. Visual acuity, slitlamp examinations, tonometry, and corneal thickness were observed. Simulated keratometric and topographic index values were detected with corneal topography. Uncorrected, LogMAR visual acuity has improved from +0.8 to +0.55 during the 6 months and +0.3 during the 8 months follow-up after CXL. Pachymetry values and intraocular pressure showed no changes. Keratometric values and topografic indexes disclosed no progression of the disease. CXL may postpone or eliminate the need of corneal transplantation in cases with PMD.

Aim: To provide the normative data of macular and retinal nerve fiber layer (RNFL) thickness in Indians using spectral domain OCT (Spectralis OCT, Heidelberg Engineering, Germany) and to evaluate the effects of age, gender, and refraction on these parameters. Design: Observational, cross-sectional study. Materials and Methods: The eyes of 105 healthy patients aged between 20-75 years, with no ocular disease and best corrected visual acuity of 20/20, were scanned using standard scanning protocols by a single examiner. Exclusion criteria included glaucoma, retinal diseases, diabetes, history of prior intraocular surgery or laser treatment. The mean macular and RNFL thickness were recorded, and the effects of age, gender, and refraction on these parameters were evaluated. This data was compared with published literature on Caucasians to assess the ethnic variations of these parameters. Results: The normal central foveal thickness in healthy Indian eyes measured using Spectralis OCT was 260.1 ± 18.19 ΅m. The nasal inner quadrant showed maximum retinal thickness (338.88 ± 18.17 ΅m).The mean RNFL thickness was 101.43 ± 8.63 ΅m with maximum thickness in the inferior quadrant. The central foveal thickness showed a gender-based difference (P = 0.005) but did not correlate significantly with age (P = 0.134), whereas the parafoveal, perifoveal thickness, macular volume, and RNFL thickness showed significant negative correlation with age. Conclusions: Our study provides the normative database for Indians on Spectralis OCT. It also suggests that age should be considered while interpreting the macular thickness and RNFL, whereas gender should also be given consideration in central foveal thickness.

Purpose: To investigate the effect of optic neuritis (ON), ischemic optic neuropathy (ION) and compressive optic neuropathy (CON) on multifocal visual evoked potential (mfVEP) amplitudes and latencies, and to compare the parameters among three optic nerve disorders. Materials and Methods: mfVEP was recorded for 71 eyes of controls and 48 eyes of optic nerve disorders with subgroups of optic neuritis (ON, n = 21 eyes), ischemic optic neuropathy (ION, n = 14 eyes), and compressive optic neuropathy (CON, n = 13 eyes). The size of defect in mfVEP amplitude probability plots and relative latency plots were analyzed. The pattern of the defect in amplitude probability plot was classified according to the visual field profile of optic neuritis treatment trail (ONTT). Results: Median of mfVEP amplitude (log SNR) averaged across 60 sectors were reduced in ON (0.17 (0.13-0.33)), ION (0.14 (0.12-0.21)) and CON (0.21 (0.14-0.30)) when compared to controls. The median mfVEP relative latencies compared to controls were significantly prolonged in ON and CON group of 10.53 (2.62-15.50) ms and 5.73 (2.67-14.14) ms respectively compared to ION group (2.06 (-4.09-13.02)). The common mfVEP amplitude defects observed in probability plots were diffuse pattern in ON, inferior altitudinal defect in ION and temporal hemianopia in CON eyes. Conclusions: Optic nerve disorders cause reduction in mfVEP amplitudes. The extent of delayed latency noted in ischemic optic neuropathy was significantly lesser compared to subjects with optic neuritis and compressive optic neuropathy. mfVEP amplitudes can be used to objectively assess the topography of the visual field defect.

Purpose: To evaluate the outcome of strabismus surgery for congenital superior oblique palsy (SOP) in relation to correction of head tilt and hypertropia. The cohort of patients mainly involved very young children. This is the first study to use a standardized instrument to objectively measure torticollis before and after surgery. Materials and Methods: A non-comparative interventional case series of 13 cases of congenital superior oblique palsy with head tilt, who underwent simultaneous superior oblique tuck and inferior oblique recession between Jan 2000 and Dec 2008, were studied. Results: The mean duration of SOP until surgery was 36.8 months. Of the 12 unilateral cases, 8 were right-sided. Mean follow-up period was 17 months (range 7-36). The outcome was determined at the last follow-up. Mean pre-and post-operative hypertropia (p.d.) in forced primary position was 19 ± 7 and 2 ± 6, respectively ( P < 0.0001). The head tilt reduced from mean of 17 ± 9 to 2 ± 2 degrees ( P < 0.0001). Success, defined as hypertropia

Aim: To evaluate the relationship between intraocular pressure (IOP) and systemic health parameters such as age, gender, body mass index (BMI), total cholesterol, high density lipoprotein (HDL), and triglyceride (TG) in a Korean population. Materials and Methods: A total of 30,893 healthy subjects underwent automated multiphasic tests, including non-contact tonometry, automated perimetry, fundus photography, and blood samplings for total cholesterol, HDL, and TG. Seven age groups were divided by decades ranging from 20 to 29 years to 80 + years. The association between IOP and BMI, plasma lipid profiles was examined using cross-sectional analysis. Results: The mean age of subjects was 47.7 years. The mean IOP of subjects was 15.4 ± 3.2 mmHg for both eyes. The mean IOP of men was significantly higher than women ( P = 0.000). By multiple linear regression analysis, IOP was positively associated with gender (male), BMI, total cholesterol, and TG and negatively associated with age ( P = 0.000). BMI, total cholesterol, and TG had significantly positive correlations with IOP after adjusting for age, gender, and other variables which can influence the IOP ( P = 0.000). Conclusions: In a Korean population, the mean IOP, total cholesterol, TG, and BMI values of men were higher than women. IOP was found to increase with total cholesterol, TG, BMI, and to decrease with only age regardless of sex.

A 35-year-old female was referred to our hospital with bilateral loss of vision of two days duration. She gave history of consumption of about 150 ml of neem oil five days back.Examination revealed no perception of light in both eyes. Both pupils were dilated and sluggishly reacting to light. Her fundus examination showed bilateral hyperemic, edematous discs and also edema extending along the superior and inferior temporal vascular arcade. Magnetic resonance imaging (MRI) scan showed bilateral putaminal regions with altered signal, hypointensities in T1-weighted images, hyperintensities on T2-weighted, images and hyperintense on Fluid Attenuation Inversion Recovery (FLAIR) images suggestive of cytotoxic edema due to tissue hypoxia. Her vision improved to 20/200 in both eyes with treatment after two months. This is the first case report of such nature in the literature to the best of our knowledge.

While invasive aspergillosis occurs typically in severely immunocompromised patients, cases of surgical site infections have been reported in immunocompetent individuals. The purpose is to report an eye with post-operative Aspergillus endophthalmitis, which achieved a good visual outcome following early and aggressive treatment. A young patient, known case of allergic bronchopulmonary aspergillosis presented to us with post-cataract surgery endophthalmitis. He was treated with pars plana vitrectomy and intravitreal voriconazole and systemic itraconazole. The patient regained a vision of 20/30 with follow up of 2 years.

A 65-year-old lady presented with decreased vision in left eye since seven months. Vision was 6/9 in right eye and 6/36 in left. Examination revealed idiopathic, full-thickness macular hole in left eye; confirmed by optical coherence tomography (OCT). Patient underwent phacoemulsification with intraocular lens (IOL) implantation, vitrectomy, internal limiting membrane (ILM) peeling and 14% C 3 F 8 gas injection. OCT repeated after six weeks revealed type II closure with cuff of subretinal fluid. Four weeks later, patient underwent fluid-gas exchange with 14% C 3 F 8 gas and postoperative positioning. OCT was repeated after two weeks, which showed complete closure of the macular hole. OCT can help in selection of eyes for re-surgery that stand a better chance for hole closure. Macular holes with cuff of subretinal fluid are probably more likely to close on re-surgery than those without. However, larger studies with longer follow-up are required to validate this finding.

Nager syndrome, also called preaxial acrofacial dysostosis, comprises two groups of defects involving the limbs and craniofacial region, respectively. This syndrome is rare and only 70 cases have been reported in the literature. The exact cause of this syndrome is unknown, but there is indication that it is genetically based. Ocular manifestations of this syndrome include widely separated downward slanting eyes, absence of eyelashes, ptosis of upper eyelids and colobomas on the inner aspect of lower eyelids. We report limbal dermoid in a patient with Nager syndrome. We did not find such an association of "Limbal dermoid in Nager acrofacial dysostosis syndrome" on PubMed using Nager acrofacial dysostosis, limbal dermoid and ocular manifestations as the keywords.

A 57-year-old male patient visited our clinic for decreased visual acuity in the right eye for 10 days. He denied any trauma history, but recalled that the symptom developed after straining. He had undergone uncomplicated phacoemulsification and posterior chamber intraocular lens (IOL) implantation in the bag of the right eye 11 years ago. The IOL was a three-piece silicone polyimide-haptics design. On slit-lamp examination, the IOL optic and proximal part of nasal fractured haptic were found in the anterior chamber. The distal part of fractured haptic was observed in the capsular bag. He underwent IOL exchange. The fracture site of the haptic was near the optic-haptic junction. This is the unique case report of a spontaneous fracture of an implanted posterior chamber polyimide IOL haptic, which implies the possibility of IOL haptic fracture in various haptic materials.

Blepharophimosis ptosis epicanthus inversus syndrome (BPES) is a complex eyelid malformation characterized by the classical tetrad of blepharophimosis, telecanthus, ptosis, and epicanthus inversus. It has been reported to be associated with other ocular anomalies such as euryblepharon, strabismus, nystagmus, amblyopia, microphthalmos, lacrimal drainage apparatus abnormality, extra ocular muscle abnormalities, microcornea, trabecular dysgenesis, optic nerve hypoplasias, and colobomas of the optic disk. We describe a case of BPES with Axenfeld-Rieger syndrome, a neurocristopathy characterized by maldevelopment of the anterior segment with predisposition to development of glaucoma. Interestingly, both syndromes are caused by mutations in the same class of genes, namely the winged-helix/forked transcription factors (FOX) involved in a variety of developmental processes.

Cholesterol granuloma is a rare, well-defined lesion of the orbit. In the orbit, diploe of the frontal bone is involved almost exclusively. We report an atypical case of cholesterol granuloma involving superomedial quadrant of orbit. A 42-year-old male presented with progressive, painless, proptosis with infero-temporal displacement of left eye. A large mass was felt beneath the bony orbital margin in the superomedial quadrant of the left orbit. Computerized tomography (CT) scan revealed an extraconal superomedial, heterogeneous enhancing mass which was isodense with brain and pushing the globe inferolaterally and anteriorly. Excision biopsy of the tumor revealed the typical features of a cholesterol granuloma without any epithelial elements. Cholesterol granuloma of the orbit is a rare entity, but it can be diagnosed and differentiated from other lesions of the superior orbit by its characteristic clinical, radiological and histopathological features. An appropriate intervention in time carries a good prognosis with almost no recurrence.

A 65-year-old man developed capsular block syndrome in the early postoperative period, following phacoemulsification surgery. After neodymium-doped yttrium aluminum garnet (Nd:YAG) laser anterior capsulotomy, the intraocular pressure remained elevated for 4 days despite antiglaucomatous medication. On the postoperative fifth day, nonarteritic ischemic optic neuropathy was diagnosed. To the best of our knowledge, this is the first report of a case with nonarteritic ischemic optic neuropathy associated with early postoperative capsular block syndrome after phacoemulsification surgery.

Annular elastolytic giant cell granuloma is a condition characterized histologically by damaged elastic fibers associated with preponderance of giant cells along with absence of necrobiosis, lipid, mucin, and pallisading granuloma. It usually occurs on sun-damaged skin and hence the previous name actinic granuloma. A similar process occurs on the conjunctiva. Over the past three decades only four cases of conjunctival actinic granuloma have been documented. All the previous patients were females with lesions in nasal or temporal bulbar conjunctiva varying 2-3 mm in size. We report a male patient aged 70 years presenting with a 14 mm × 7 mm fleshy mass on right lower bulbar conjunctiva. Clinical differential diagnoses were lymphoma, squamous cell carcinoma in situ and amyloidosis. Surgical excision followed by histopathology confirmed it to be a case of actinic granuloma. This is the first case of isolated conjunctival actinic granuloma of such a large size reported from India.

We report the first case, in Medline-based literature, of conjunctivitis caused by gram negative diplococcus, Neisseria sicca. Although it is not widely accepted as such, isolation from cultures of repeated eye swab samples suggests that N. sicca may be a pathogen in conjunctival infections. Positive culture for this organism should not be readily dismissed. Such conjunctivitis responded favorably to treatment with netilmicin eye drops.

We are reporting an interesting case of ichthyosis follicularis with alopecia and photophobia syndrome in a daughter and father from the Indian subcontinent associated with Meibomian gland dysfunction. A three-year-old female child presented with pain, redness and severe photophobia in both eyes since one month. Cutaneous examination revealed ichthyosis, absence of hair all over the body including eyebrows, scalp and angular cheilosis. Ocular examination revealed bilateral severe meibomianitis, multiple superficial punctate keratitides in right eye and corneal epithelial defect in the left eye. Other systemic features were prominent high forehead and large ears. Her father had similar symptoms. Her symptoms improved after adequate treatment of meibomian gland dysfunction. She is asymptomatic at present.

Introduction:The early detection of glaucoma is imperative for functional vision preservation. Utilizing both structural measurements and functional assessments together improve the capability of glaucoma detection. New testing methods are continuously developed with the goals of earlier disease detection and improvement of disease monitoring. Areas covered:A comprehensive literature review on the relationship between structural and functional glaucoma measures and important recent technological advances in early glaucoma detection. Expert commentary:Advancements utilizing optical coherence tomography have allowed the analysis of new structural parameters that can sensitively detect changes in optic nerve and retinal structures. More objective vision assessment methods have the potential to supplement and predict the results of standard automated perimetry. More research is necessary to understand the clinical utility of these advancements for glaucoma management. [ABSTRACT FROM PUBLISHER]

Background The multifocal visual evoked potential ( mfVEP) is a useful tool for evaluating optic nerve disease and visual defects secondary to optic nerve or retinal ganglion cell damage. Objective The aim of this study was to establish technical guidelines and normative values of the peak time and amplitude of the mfVEP in adolescents. Participants and methods This is a prospective study conducted on 20 healthy adolescents (40 eyes) 10 girls and 10 boys. Their age ranged between 10 and 15 years with a mean of 12.50 ± 1.48. Monocular mfVEP was obtained from each eye separately. The peak time and amplitude of the P1 wave of each individual response were measured and then expressed in the form of four quadrants. Results The peak time and amplitude of the P1 wave showed no statistical differences between the four quadrants and no correlation to the age. There were no statistically signifi cant differences between girls and boys or between left and right eyes regarding the peak time and the amplitude of the P1 wave. Conclusion We obtained normative data of mfVEP of the adolescents in our lab as a preliminary work for further application in different neuro-ophthalmological disorders. [ABSTRACT FROM AUTHOR]

Purpose: In previous studies, we applied receiver operating characteristic curve analysis to the signal-to-noise ratio distributions in the signal and noise windows of multifocal VEP (mfVEP) response. The areas under the curve thus obtained (SNR-AUC) were found to quantitatively detect glaucomatous visual field damage. The present study evaluated the reproducibility of SNR-AUC and the Humphrey visual field (HVF) global indices in 37 eyes with primary open angle glaucoma (POAG; POAG group) and in 30 controls (control group) within a 2-year period. Methods: The HVF SITA standard 24-2 and mfVEP were recorded at three separate sessions for each individual. The intersession variability for SNR-AUC, mean deviation (MD), and pattern standard deviation (PSD) was evaluated using the repeated measures of analysis of variance and Bland-Altman plots. The logarithmically converted coefficients of variation (CV) of PSD and SNR-AUC were compared between the control and POAG groups. Linear regression analyses were performed on the logarithmic CV of SNR-AUC against the average MD, PSD, and SNR-AUC. Results: SNR-AUC in the POAG group was significantly lower and its CV was greater compared with the control group ( P < 0.0001). MD value recorded at the third visit had significantly improved than that at the first visit in the control group (analysis of variance, P = 0.03), whereas PSD value was significantly worse in the POAG group ( P = 0.024). In the POAG group, SNR-AUC CV increased as the glaucoma stage became more advanced when evaluated by any functional parameters tested (i.e., MD, PSD, or SNR-AUC). Conclusions: The SNR-AUC of mfVEP showed a high reproducibility in control group, whereas it fluctuated more in the POAG group according to the disease severity. MD in the control group and PSD in POAG group fluctuated among sessions during the 2-year period. [ABSTRACT FROM AUTHOR]

Purpose: To establish reproducibility of multifocal visual evoked potential (mfVEP) and traditional pattern-reversal VEP (tVEP) in normals and relapsing-remitting multiple sclerosis (RRMS). Methods: mfVEP (60-sector dartboard) was recorded twice within a month in 40 normals and 40 RRMS patients [25 eyes with last optic neuritis (ON) ≥6 months, 34 non-ON]. mfVEP amplitude and latency (ms) were calculated as mean logSNR and median relative latency, respectively, for all 60 sectors (global) and 9 regions. tVEP was recorded (15′, 60′ and 120′ checks) in subsets of 34 normals and 30 RRMS patients. tVEP N75-P100 amplitude (µV) and P100 latency (ms) were obtained. Reproducibility was evaluated using intraclass correlation coefficient (ICC) and test-retest variability (TRV). ICC ≥ 0.75 was considered good. Results: ICCs for global and regional mfVEP were >0.80 in all groups. ICCs for tVEP were >0.75 for all except latency in ON (0.52-0.68). For mfVEP or tVEP, TRV for amplitude was similar among all groups; TRV for latency (ms) was larger in ON (5.3 for mfVEP global, 10.3 for 60′ tVEP) compared with non-ON (3.1, 8.3) and normal (2.3, 5.7) ( p < 0.05 for all). When tVEP was analyzed using similar methods as mfVEP (logSNR and relative latency), mfVEP global measures showed better ICC and TRV than tVEP in all groups. Conclusions: mfVEP and tVEP showed good reproducibility in normals and RRMS. TRV for mfVEP latency was larger in ON than normal or non-ON. mfVEP global latency's TRV was about half the respective values for tVEP in all groups, due to averaging of multiple responses. [ABSTRACT FROM AUTHOR]

Objective Visual search can be guided by past experience of regularities in our visual environment. This search guidance by contextual memory cues is impaired by foveal vision loss. Here we compared retinal and cortical visually evoked responses in their predictive value for contextual cueing impairment and visual acuity. Methods Multifocal electroretinograms to flash stimulation (mf ERGs; 103 locations; 55.8° diameter) and visual evoked potentials to pattern-reversal stimulation (mf VEPs; 60 locations; 48.6° diameter) were recorded monocularly in participants with age-related macular degeneration ( n = 14 and 16, respectively). Response magnitudes were calculated as the respective signal-to-noise ratios for each eccentricity. Visual acuities (log MAR, range: 0.0-1.2) and contextual cueing effects on visual search (reaction time gain, range: −0.14-0.15) were correlated with the signal-to-noise ratios. A step-wise regression analysis was applied separately to the mf ERG- and mf VEP-dataset to determine the eccentricity range and the processing stage that is critical for these visual functions. Results Central mf ERGs (1.0-3.2°) were the sole predictor of contextual cueing of visual search ( p = 0.006), but they were not significant predictors of visual acuity. In contrast, central mf VEPs (1.3-3.2°) were the sole predictor of visual acuity ( p < 0.001), but they were not significant predictors of contextual cueing. Conclusions Contextual cueing is more dependent on parafoveal mf ERG magnitude while visual acuity is more dependent on parafoveal mf VEP magnitude. The relation of contextual cueing to parafoveal mf ERG magnitudes indicates the predictive value of retinal bipolar cell activity for this advanced level of visual function. [ABSTRACT FROM AUTHOR]

Background: We have previously reported that the degree of signal-to-noise ratio (SNR) distribution overlaps between a signal window and a noise window in multifocal VEP (mfVEP) responses, which is determined by the area under the receiver-operating characteristic curve termed SNR-AUC, can quantitatively detect glaucomatous visual functional damage. However, the effect of high myopia on this parameter is not yet known. Methods: SNR-AUC, total deviation, and retinal sensitivity on the Humphrey visual field (HVF) test were compared among 34 eyes >−6 diopters (control) and 21 eyes ≤−6 diopters (high myopia), both of which were ophthalmoscopically normal and had a best-corrected visual acuity of 20/20. The mfVEP and HVF parameters were obtained from stimulus areas that corresponded to both HVF 24-2 and 10-2 programs. Results: Both the HVF 24-2 total deviation and the SNR-AUC obtained from 60 sectors in high-myopia patients were significantly lower compared with controls ( P = 0.045 and P = 0.003, respectively). The SNR-AUC obtained from the central 36 sectors that corresponded to the HVF 10-2 area in high-myopia patients was also significantly lower than that of the controls ( P = 0.01). Multiple regression analyses demonstrated that age and refractive error were significantly associated with retinal sensitivity on the HVF 24-2 and SNR-AUC for the whole field and central field, respectively. Conclusions: High myopia reduces the SNR-AUC of mfVEP responses, even with refractive correction. A normative database should be separately established for high myopes to evaluate the mfVEP responses obtained from highly myopic glaucoma patients. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effect of optic neuritis (ON), ischemic optic neuropathy (ION) and compressive optic neuropathy (CON) on multifocal visual evoked potential (mfVEP) amplitudes and latencies, and to compare the parameters among three optic nerve disorders. Materials and Methods: mfVEP was recorded for 71 eyes of controls and 48 eyes of optic nerve disorders with subgroups of optic neuritis (ON, n = 21 eyes), ischemic optic neuropathy (ION, n = 14 eyes), and compressive optic neuropathy (CON, n = 13 eyes). The size of defect in mfVEP amplitude probability plots and relative latency plots were analyzed. The pattern of the defect in amplitude probability plot was classified according to the visual field profile of optic neuritis treatment trail (ONTT). Results: Median of mfVEP amplitude (log SNR) averaged across 60 sectors were reduced in ON (0.17 (0.13-0.33)), ION (0.14 (0.12-0.21)) and CON (0.21 (0.14-0.30)) when compared to controls. The median mfVEP relative latencies compared to controls were significantly prolonged in ON and CON group of 10.53 (2.62-15.50) ms and 5.73 (2.67-14.14) ms respectively compared to ION group (2.06 (-4.09-13.02)). The common mfVEP amplitude defects observed in probability plots were diffuse pattern in ON, inferior altitudinal defect in ION and temporal hemianopia in CON eyes. Conclusions: Optic nerve disorders cause reduction in mfVEP amplitudes. The extent of delayed latency noted in ischemic optic neuropathy was significantly lesser compared to subjects with optic neuritis and compressive optic neuropathy. mfVEP amplitudes can be used to objectively assess the topography of the visual field defect. [ABSTRACT FROM AUTHOR]

This is a single case report of an elderly patient who had blunt trauma in an eye that had phacoemulsification and two trabeculectomies. She had good vision with a well-functioning bleb before the trauma. She presented during her routine follow-up visit for glaucoma with isolated aniridia and an intact globe. The capsular bag, zonules, and the intraocular lens were intact. The cupping was 0.8, and the rest of the fundus and macula were normal. Pigments were seen over the sclera extending posteriorly upto the fornix. Gonioscopy revealed only faint pigments at the fistula. Following the trauma, the intraocular pressure had increased to 26 mm Hg. The mechanism and the management of the glaucoma are discussed.

Ocular dirofilariasis mostly presents as a subconjunctival or eyelid lesion. [1] Intraocular dirofilarial infestation is rare. [2],[3] We report a case of a young woman who was accidentally detected to have a live motile worm in the anterior segment in one eye and a cystic lesion on the optic disc in the other eye. To our knowledge, bilateral intraocular dirofilariasis has never been reported.

Implantation of iris-claw Artisan intraocular lens (IOL) is a surgical option for correction of aphakia; however, these IOLs have not been used in eyes with uveitis including Fuchs′ heterochromic iridocyclitis (FHI) due to possible risk of severe postoperative intraocular inflammation. In the case reported here, we secondarily implanted an Artisan IOL in a 28-year-old man with FHI who had aphakia with no capsular support due to a previous complicated cataract surgery. Enclavation was easily performed and no intraoperative complication was noted. Postoperative course was uneventful with no significant anterior chamber inflammation during 12 months of follow-up. Although there were few deposits on the IOL surface, the patient achieved a best-corrected visual acuity of 20/20 without developing glaucoma or other complications. Therefore, Artisan IOL may be considered for correction of aphakia in patients with FHI. However, studies on large number of patients are required to evaluate safety of the procedure.

Visual electrophysiology allows non-invasive monitoring of the function of most processing stages along the visual pathway. Here, we consider which of the available methods provides the most information concerning glaucomatous optic nerve disease. The multifocal electroretinogram (ERG), although often employed, is less affected in glaucoma than two direct measurements of retinal ganglion cell function, namely the pattern ERG (PERG) and the photopic negative response (PhNR) of the ERG. For the PERG, longitudinal studies have been reported, suggesting that this method can be used for the early detection of glaucoma; for the PhNR, no longitudinal study is available as yet. The multifocal PERG can spatially resolve ganglion cell function but its glaucomatous reduction is typically panretinal, even with only local field changes and so, its topographic resolution is of no advantage in glaucoma. The multifocal visual evoked potential promises objective perimetry and shows sensitivity and specificity comparable with standard automated perimetry but has not been established as a routine tool to date. [ABSTRACT FROM AUTHOR]

To test whether multifocal visual evoked potential (mfVEP) recording using two perpendicularly placed channels, as previously reported, to measure the degree of signal-to-noise ratio (SNR) distribution overlap between a signal window and a noise window would efficiently detect and quantify glaucomatous damage. Humphrey visual field (HVF) and mfVEP were recorded from 56 patients with primary open-angle glaucoma and mean deviation less than −15 dB and 62 age-matched ophthalmologically normal individuals. Areas under the receiver-operating characteristic curve (SNR-AUC) were calculated based on the proportion of mfVEP responses that exceeded a specific SNR criterion for both windows. Abnormal sectors with an SNR deviated from the previously established norm with P < 5% and 1% were counted. Diagnostic accuracy of the SNR-AUC was similar to that of the average total deviation (TD) of the HVF. The hemifield agreement to detect a defect in mfVEP and HVF was 77.1-87.3%, which was similar to previous reports using multiple channels. Correlation coefficients between SNR-AUC and average TD (0.74 in the upper hemifield and 0.65 in the lower) were significantly higher than those between the sums of abnormal locations on the mfVEP and HVF probability plots (0.27 and 0.33, respectively). Two perpendicular channels can detect and quantify functional damage due to glaucoma. The SNR-AUC may be used as a global index to quantify diffuse glaucomatous functional loss. [ABSTRACT FROM AUTHOR]

The purpose of this study was to establish optimal conditions for recording multifocal visual evoked potentials (mVEPs) in Japanese individuals, whose skull frame presumably differs from Caucasians. The scalp point that was extended from the calcarine fissure was identified using magnetic resonance imaging scans of 200 subjects. MVEPs were recorded from 56 individuals using three single channels and combinations of vertical and horizontal channels. Five electrodes were placed at the inion, 4 cm above the inion, 2.5 cm below the inion, 4 cm to the left or 4 cm to the right of the inion. The signal-to-noise ratio (SNR) was obtained by measuring the root-mean-square (RMS) amplitude of a signal window (45-150 ms) from each of 60-local responses that was divided by the average of the 60 RMS amplitudes of the noise window (325-430 ms). Receiver operating characteristic (ROC) analyses were performed based on the proportion of mVEP responses that exceeded a specific SNR criterion, calculated for both the signal window and the noise window. The position of the calcarine fissure relative to the inion was significantly lower than the value reported for Caucasians. The ROC analyses disclosed that bi-channel combinations (one vertical and one horizontal) had significantly better performance to discriminate signal from noise in 60-local mVEP responses compared to any single channel and performed similarly to the tri-channel combination. Two sets of perpendicular channels should be simultaneously used in recording mVEP responses from Japanese people, among whom skull frame characteristics differ from those observed in Caucasians. [ABSTRACT FROM AUTHOR]

Abstract: mfVEPs were recorded with a 22° radius, 60 sector pattern reversal dartboard stimulus (VERIS) at six contrast levels (10%, 25%, 35%, 50%, 75%, 95%). Contrast response functions (CRFs) based on response amplitudes were adequately described by a simple hyperbolic function. The effect of reducing contrast on the amplitude was most apparent in the central 1° radius, which had a C 50 (contrast at 50% of the maximum response) in excess of 50%, compared to values for C 50 in more eccentric regions that were 30% or lower. Mean latency increased 6 (±0.7SE) ms from the highest to the lowest contrast tested, and did not vary significantly with eccentricity. [Copyright &y& Elsevier]

Glaucoma is a complex disease with multifactorial etiology; at present, the intraocular pressure is the only treatable risk factor. If detected early, disease progression can frequently be arrested or slowed with medical and surgical treatment. Therefore, key aspects of glaucoma management are early detection of disease and monitoring of its progression, including evaluation of treatment effectiveness. In this context, electrophysiological testing may provide specific and unique information. The past few years have seen an increasing interest in electrophysiological testing in glaucoma. This article will provide a review of recent developments in the field. [ABSTRACT FROM AUTHOR]

Abstract: Differences in cortical geometry within and between subjects can complicate multifocal visual evoked potential (mfVEP) and standard evoked potential (EP) intra- and inter-subject comparisons. We present methods for aligning temporal intra- and inter-subject data prior to comparison. Multiple groups have informally observed that the two dominant temporal principal components (PCs) of the pattern reversal visual evoked potential (VEP) obtained with singular value decomposition (SVD) exhibit little inter-subject variability relative to the inter-subject variability of the raw VEP. We present methods that employ the temporal PCs to formally quantify intra- and inter-subject variability of the mfVEP. When SVD was applied to data from eight subjects separately, it was found that two PCs accounted for, on average, 73% of intra-subject variance. When a single SVD was applied to combined data from multiple subjects, it was found that two PCs accounted for 67% of inter-subject variance. We used the 2D temporal subspaces derived from SVD as a basis for intra- and inter-subject comparisons. [Copyright &y& Elsevier]

Abstract: We examined the effects of inter-modal attention and mental arithmetic on Humphrey visual field sensitivity and multifocal visual evoked potential (mfVEP) amplitude. Four normally sighted subjects (ages ranging from 24 to 58years) participated in this study. Monocular visual field sensitivity was measured under two conditions: (1) standard testing condition and (2) while the subject performed a Paced Auditory Serial Addition Task (PASAT). Monocular mfVEPs were recorded in response to a 60-sector stimulus. The checkerboard pattern in each sector was contrast reversed according to a binary m-sequence. mfVEPs were recorded under two conditions: (1) standard testing conditions and (2) while the subject performed a PASAT. We found that, when compared to the no-task condition, all subjects had locations of significantly reduced Humphrey visual field sensitivities when performing the PASAT. In contrast, there were no significant decreases in mfVEP amplitude in any sector for any of the subjects while performing the PASAT. Our findings indicate that divided attention and ongoing mental processes did not affect the mfVEP. Therefore, the mfVEP provides an objective measure of visual field function that may be useful for some patients with unreliable automated static perimetry results. [Copyright &y& Elsevier]

Objective: To characterize the clinical phenotype, with emphasis on electrophysiology and blood flow measurements, of a family with dominant optic nerve atrophy and an identified mutation in the OPA1 gene. Methods: Seven family members were examined. Ophthalmological evaluation included testing of visual acuity, ophthalmolsocopy, kinetic perimetry, color vision testing, full-field electroretinography (ERG), multifocal electroretinography (MERG), and multifocal visual evoked potential (MVEP). Retrobulbar arterial blood flow and retinal capillary perfusion was measured in three patients using scanning laser Doppler flowmetry (SLDF) and color Doppler imaging techniques. PCR-SSCP and DNA sequencing determined the presence of a mutation in exon 18 of the OPA1 gene. Results: The clinical characteristics varied considerably in the family. The ERG and the MERG demonstrated normal retinal function, while the MVEP was abnormal in all examined patients. Retinal and optic nerve head capillary perfusion was significantly decreased in the three patients examined with SLDF. Retrobulbar blood flow velocities were significantly decreased in the central retinal and ophthalmic arteries. In all seven examined subjects, a microdeletion (1756-1767del(12 bp)) in the OPA1 gene was identified. Conclusion: Patients with a mutation in the OPA1 gene have a very variable phenotype. MVEP and blood flow measurements are two new objective methods for an easier detection of this specific genetic optic nerve atrophy. [ABSTRACT FROM AUTHOR]

Abstract The non-linearities of the diffuse flash visual evoked potential (VEP) have been shown to generate separable waves corresponding to Magnocellular and Parvocellular contributions. The authors wished to investigate whether, under conditions of isoluminance, the chromatic pattern appearance VEP shows waveforms that are related to both the processing of contours (the pattern) and the processing of the diffuse stimulation (from the area lying between the contours). The VERIS multifocal system was used to record monocular VEP. Standard 2-ring, 3-ring, 5-ring and 7-ring VERIS pattern stimuli were employed with a cardboard circular aperture used to blank the stimulus monitor to a 9-cm diameter field. The results for four subjects were recorded. The first order kernel responses showed a significant increase in amplitude with total contour length. In comparison, the amplitudes of the first and second slices of the second order kernel did not increase with contour length. It appears that the contour-dependent component has negligible non-linear components. It is proposed that the constant, non-zero responses of the higher order kernel components reflects contributions from the diffuse chromatic VEP. [ABSTRACT FROM AUTHOR]