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B Wabbels

Publications and source records attributed to B Wabbels.

10 recordsLinked to original sources
PubMed2006

Genotype-phenotype correlation and longitudinal course in ten families with Best vitelliform macular dystrophy.

AIM: Longitudinal course and genotype-phenotype correlation in patients and carriers with heterozygous mutations in hBEST1 (bestrophin). METHODS: Thirteen patients and seven possible carriers were characterised by mutation analysis with SSCPA and direct sequencing, clinical examination and fundus autofluorescence (AF). Electrophysiology (EOG and mfERG) and optical coherence tomography (OCT) were additionally performed whenever possible. RESULTS: We identified seven different heterozygous mutations in ten unrelated families with Best disease. I296del was the most frequent mutation. Five of nine individuals with I295del and two of three with N99K were asymptomatic carriers. One patient with I295del mutation had funduscopically unilateral Best disease. In three children (all with I295del), EOG initially showed a clearly present light peak that deteriorated during 5 years of follow-up in two of them. Increased AF corresponded well to funduscopically visible lesions. During 3-6 years of follow-up, the lesion area did not change significantly, but there were obvious changes in the inner structure of the lesion. CONCLUSION: In the present series I295del, the most frequent mutation in our study, and N99K showed reduced penetrance. EOG was normal in young patients even if prime signs were visible. The lesion area did not depend on the mutation and did not correlate with VA. Lower VA was associated with a more irregular AF pattern due to scarring or haemorrhage. Our results indicate a disease causing effect that is cumulative over time.

Adolescent↗
PubMed2006

[Conventional perimetry. Part 3: Static perimetry: grid--strategy--visualisation].

Methods for visual field examination using static strategies began with manual static profile perimetry. The transition from a linear stimulus alignment along the profile section to a two-dimensional grid arrangement introduced the era of static grid perimetry. The use of computers makes it possible to automate and standardise this process, allowing the examiner to choose the visual field area, an adequate grid and the optimal strategy, while leaving the processing, visualisation and recording completely observer-independent. This contribution is based only on conventional static procedures for visual field examination (the use of white on white perimetry) as this technique is easily accessible, standardised and well established in everyday practice.

Diagnosis, Computer-Assisted↗
PubMed2006

[Conventional techniques of visual field examination: part 4 Static perimetry: interpretation--perimetric indices--follow-up--perimetry in childhood].

Visual field examination with fixed stimuli was first realized in manual static profile perimetry. The transition from a linear stimulus alignment along a profile section towards a two-dimensional arrangement introduced the era of static grid perimetry. Application of computer technology nowadays allows automation and standardization of this procedure, which enables the examiner to select the necessary visual field area, the adequate grid, and the optimal strategy for an estimation of differential luminance sensitivity. Furthermore, the computer independently takes over the recording, visualization, and processing of the perimetric procedure. This contribution discusses conventional static visual field examinations since these are widely used, easily accessible, well established for practical application, and standardized. This paper (part 4) explicitly focuses on the correct interpretation of automated static strategies of visual field examinations. Furthermore the classification and scoring of visual field defects as well as quality control, progression analysis, and perimetry in childhood are addressed. This manuscript is based on three preceding parts, which were published in previous issues of this journal [27, 28, 29].

Child↗
PubMed2001

[Automated kinetic perimetry using different stimulus velocities].

INTRODUCTION: Because kinetic perimetry is performed manually, it is difficult to standardize. This study evaluated the effect of different velocities of various stimuli on the results of automated kinetic perimetry. MATERIALS AND METHODS: Twelve ophthalmologically healthy subjects were tested with stimuli III4, I4, I2, I1 using the Twinfield perimeter at velocities of 1-7 degrees/s. RESULTS: Results of stimuli III4 and I4 were not dependent on velocity. Concerning stimuli I2 and especially I1 the isopters were narrower for increasing velocity, and variance in results was greater above 4 degrees/s. CONCLUSION: The recommended velocity of 2 degrees/s is often exceeded in daily clinical practice, which explains part of the variation in findings between studies. Automated kinetic perimetry could ensure a constant, slower velocity and thus improve standardization.

Humans↗
PubMed2000

[Painless orbital swelling after sojourn in tropics. Cysticercosis and other parasitic eye diseases].

BACKGROUND: The differential diagnosis of painless orbital swelling is complex and based on radiological and physical examination as well as laboratory tests. Due to increasing tourism to exotic countries a thorough history is important to observe diseases which are rare in industrialised countries but frequent in developing countries. PATIENT: A 30-year-old man complained about a painless orbital swelling in the absence of general symptoms. Orbital examination revealed a normal globe. MRI scan and B-scan ultrasounds showed an orbital cyst with a diameter of 1 cm. The patient's history disclosed lengthy travel to India as well as South East Asia. RESULTS: Histopathological examinations following excision of a whitish intraorbital mass showed a cream-white, thin walled cyst with a single central invaginated scolex with suckers and hooklets. This finding is characteristic for cysticercosis. CONCLUSIONS: Cysticercus cellulose is the larval stage of the pork tapeworm Taenia solium. It is transmitted by ingestion of contaminated food or water. Ocular affection is reported concerning the vitreous or subretinal localisation, less often in the anterior segment, subconjunctiva or orbita. Especially after trips to tropical regions, parasitic diseases should be kept in mind when dealing with unusual eye symptoms. Besides cysticercosis there are e.g. echinococcosis, onchocercosis (river blindness) and infections with toxocara or Loa loa.

Adult↗
PubMed1999

[Age-dependent error rates in automatic screen campimetry with bright and dark stimuli].

PURPOSE: To assess patient reliability and compliance, most perimeters check for false-positive and -negative answers. In this study the results of catch trials were obtained with video campimetry with respect to age-related changes and differences for tests using increment and decrement stimuli. METHODS: Sixty-one ophthalmologically normal persons (aged 20-80 years) were tested with automated campimetry on a computer screen. Examination strategy included bright and dark 1 degree-stimuli at 69 test locations within the central 30 degrees of the visual field (presented on a computer screen). Four percent of all stimulus presentations were used for testing false-positive answers, 4% for false-negative answers. RESULTS: The rate of false-positive answers was not significantly age-related and there was no difference for tests with dark and bright stimuli. Concerning false-negative answers, no difference between dark and bright stimuli was found. There was also no strong correlation with age. CONCLUSION: In this study rates of false-positive and -negative answers were low at a comparable level for either stimulus type (bright/dark) or age of the tested persons.

Adult↗
PubMed1995

Automated perimetry with bright and dark stimuli.

Conventional perimeters use bright stimuli. In this study, dark stimuli were also used. Dark stimuli are employed for testing due to their lack of effects of local scatter and are utilized with the purpose of preferentially stimulating the off-system, but their presentation with optical methods is difficult. This problem is solved by the use of a computer monitor. The objective of this study was to compare directly measurements obtained with bright and dark stimuli. Therefore, the central 30 degrees of the visual field of ten subjects with no ophthalmologic pathology was examined with bright and dark stimuli (size 10- and 30-min-of-arc). Threshold estimation was performed with the 4/2 method. Concerning the 10-min-of-arc dark stimulus, no measurement outside the central 15 degrees could be performed because of insufficient dynamic range (sometimes even the darkest stimulus was not seen). Comparing the results obtained using bright and dark stimuli of the same size, we could not find a significant difference in sensitivity for this age group.

Adaptation, Ocular↗