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Klaus W Ruprecht

Publications and source records attributed to Klaus W Ruprecht.

17 recordsLinked to original sources
PubMed2007

Prevalence of ocular manifestations in hereditary hemorrhagic telangiectasia.

BACKGROUND: Hereditary hemorrhagic telangiectasia (HHT) is a systemic disorder of the fibrovascular tissue. Few data have been published on the frequency of ophthalmologic manifestations. The aim of this study was to assess this frequency. METHODS: A prospective observational cross-sectional study was conducted in a multitude of clinical practices and in a tertiary referral center. The main outcome measure was the number of vascular malformations detected by an ophthalmologic inspection of the retina and the conjunctivae in both eyes in a random sample of patients with HHT. RESULTS: No retinal telangiectases were observed in any of the 75 patients (150 eyes) examined. Conjunctival telangiectases were detected in 28 of 74 patients (47 of 148 eyes). CONCLUSIONS: The prevalence of retinal telangiectases seems to be lower than 1/75 (< 1.3%). This data does not justify screening procedures to detect retinal telangiectases. Ophthalmologists should be aware of the symptoms of HHT and its systemic character.

Adult↗
PubMed2007

Antiphospholipid antibodies in ocular arterial and venous occlusive disease.

PURPOSE: It was the aim of this study to evaluate antiphospholipid antibodies (APA), i.e. lupus anticoagulants (LA) and anticardiolipin (ACA) IgG and IgM, in ophthalmic occlusive disease. METHODS: Over a 3.5-year period, APA were evaluated in 368 patients. RESULTS: Eighty-six patients (23.4%), compared to 5% in the general population, tested positive for APA. APA did not differ significantly between patients with venous (20.6%) or arterial (25.5%) occlusive disease. This included 93 patients with central retinal vein occlusion (18% APA positive), 67 with retinal branch vein occlusion (24% APA positive), 41 with central retinal artery occlusion (22% APA positive), 53 with retinal branch artery occlusion (32% APA positive), 71 with anterior ischemic optic neuropathy (23% APA positive), 12 with posterior ischemic optic neuropathy (33% APA positive) and 31 patients with amaurosis fugax (23% APA positive). Excluding patients with accepted main risk factors, APA were positive in 15.3% of 85 patients. CONCLUSION: The high APA prevalence confirms its relevance in ocular occlusive disorders.

Aged↗
PubMed2006

Influence of dopamine deficiency in early Parkinson's disease on the slow stimulation multifocal-ERG.

PURPOSE: In animal studies intravitreal injection of tetrodotoxin (TTX) results in mfERG waveform changes similar to those observed in glaucoma. As TTX blocks amacrine as well as ganglion cells, there is still a question regarding the underlying cell population responsible for these changes in waveform. In an attempt to assess the contribution of the amacrine cells to these changes, a mfERG was obtained from patients with Parkinson's disease as some amacrine cells are mediated by dopamine, a substance lacking in Parkinson's. METHODS: Eight patients with early Parkinson's disease underwent ophthalmologic examination, testing of contrast sensitivity and electrophysiological examination according to ISCEV standard at least 12 h following their last medication with Dopamine. A slow stimulation mfERG was obtained with a stimulus base interval of 53.3 ms and with a stimulus base interval of 106.6 ms. During MF-ERG recordings 103 hexagons stimulated the central 50 deg of the retina simultaneously and independently (m-sequence 2(13), L(max): 200 cd/m(2), approximately 100% contrast). RESULTS: Contrast sensitivity and ISCEV standard electrophysiological testing was unremarkable. When the mfERG was analyzed, only four patients had an adequate signal-to-noise ratio to allow further data analysis - one of whom was diagnosed with a multi system atrophy in retrospect. The first order response component was analyzed at a filter setting of 10-300 Hz and at 100-300 Hz (OPs) and compared to mfERGs of a control group. On average, in patients, the amplitude of N1P1 was slightly lower in the central and nasal response averages. When the three OPs at a latency of 72-89 ms were analyzed in the 53.3 ms base interval recording, the most marked difference in amplitude was observed in the superior nasal response average of the first OP. Here a mean amplitude of 1.3 nV/deg(2) in patients compared to a mean amplitude of 1.9 nV/deg(2) in the control group (P: 0.08). DISCUSSION: In contrast to our previous findings in NTG, there was a consistent presence of three OPs. Under the stimulus conditions applied, we did not find an influence of dopaminergic amacrine cells on the mfERG in our patients with moderate stages of Parkinsion's. The difficulties in obtaining an adequate signal-to noise ratio due to e.g. muscle artifacts even in Parkinson patients of moderate disease stages render a success of mfERG recording in patients with more advanced stages unlikely. The question of the influence of dopaminergic amacrine cells on the mfERG could possibly be addressed using MPDT in animal research.

Contrast Sensitivity↗
PubMed2006

Slow-stimulated multifocal ERG in high- and normal-tension glaucoma.

PURPOSE: To study the ability and sensitivity of the slow stimulation multifocal ERG (mfERG) to detect glaucomatous damage. METHODS: Right eyes of 20 patients with normal-tension glaucoma (NTG), 15 patients with high-tension glaucoma (HTG) and 15 healthy volunteers underwent testing with the mfERG (VERIS 4.1). The central 50 degrees of the retina were stimulated by 103 hexagons (m-sequence: 2(13)-1, Lmax: 100 cd/m(2), Lmin: 1 cd/m(2), background: 50 cd/m(2)). Each m-sequence step was followed by 3 black frames (Lmax: < 1 cd/m(2)). Five response averages of the first order response component (KI) were analyzed: the central 7.5 degrees and the 4 adjoining quadrants. The amplitudes from the first minimum, N1, to the first maximum, P1, and from P1 to the second minimum, N2, were analyzed as well as the latencies of N1, P1, N2 and the latencies of 3 multifocal oscillatory potentials (mfOPs) with their maxima at about 73, 80 and 85 ms. RESULTS: For each parameter the percentage of deviation from the mean of the control group was calculated. These values were then added for each individual to form a deviation index (DI). Seventeen patients (85.0%) with NTG and 3 patients (20.0%) with HTG showed a DI outside the normal range. The major changes were observed in the mfOPs of the NTG patients. MfOPs were then selectively filtered at 100-300 Hz and their scalar product was analyzed over an epoch of 68-105 ms. This confirmed that mfOPs differed significantly from the control in the central 7.5 degrees and, for NTG, in the nasal field. With a logistic regression analysis the mfOPs had a sensitivity to differentiate 85% of the NTG patients and 73% of the HTG patients from normal. CONCLUSIONS: Under these conditions, the slow-stimulated mfERG can detect glaucomatous dysfunction in NTG (85.0%). The differences observed between NTG and HTG are in support of a different underlying pathomechanism.

Adolescent↗
PubMed2005

Retinal perfusion response to a slow multifocal M-sequence flicker stimulation.

PURPOSE: To assess, if a slow multifocal stimulus (mfS) can provoke a perfusion response that can be measured with the Retinal Vessel Analyzer (RVA). METHODS: Seventeen eyes were examined. Pupils were dilated. A 120-second baseline recording was obtained with the RVA. The subject then turned to view an mfS for 56 s. The mfS consisted of 103 hexagons flickering according to an m-sequence with a stimulus base interval of 53.3 ms (L(max) = 100 cd/m(2), L(min) < 1 cd/m(2)). Immediately thereafter, the subject turned to the RVA, where measurements were resumed as soon as the same retinal vessel was targeted and continued for 104 s. Stimulation and recording was repeated twice. The diameter of a retinal vein and artery was measured for a length of at least 1 mm. The maximum vessel response was obtained by linear interpolation of the measured response within the 20 s following mfS. RESULTS: On average, veins dilated by 6.8% and arteries by 7% following mfS (p > 0.005). Such a dilatation could be observed in 9 veins and 7 arteries. Three venous and 2 arterial measurements did not show a dilatation following mfS. However, 13 of 34 measurements could not be analyzed due to signal problems or because the time from the end of mfS and the uptake of measurement exceeded 20 s. CONCLUSION: This slow multifocal ERG stimulus results in a dilatation of arteries and veins that can be measured with the RVA. Coupling an mfS to the RVA has the potential to topographically map changes in retinal perfusion in relation to the respective retinal area stimulated. When implementing the mfS into the RVA setup in order not to lose time due to the refixation in the RVA following mfS, one is required to take the transient nature of this perfusion change into consideration.

Adult↗
PubMed2004

Influence of cataract on the multifocal ERG recording--a pre- and postoperative comparison.

To study the influence of cataract on the multifocal electroretinogram (mfERG), 18 patients underwent mfERG recordings prior to and following cataract surgery. The central 50 degrees of the retina were stimulated by 103 hexagons alternating independently between white and black according to a binary m-sequence. The frame rate was 75 Hz. The maximum luminance was 200 cd/m2, the minimum luminance < 1 cd/m2 with a mean luminance of 100 cd/m2. For each retinal location, the latencies of the first negative peak (N1), the first positive peak (P1) and the second negative peak (N2) as well as the amplitude from N1 to P1 and the amplitude from P1 to N2 of the first order response were obtained. Concentric ring averages around the foveal response were analyzed. Following cataract surgery, the mean amplitude of the response in the central four degrees increased from 37.83 to 42.37 for N1P1 (p = 0.019) and from 39.44 to 47.20 for P1N2 (p = 0.001). To reduce the influence of retest variability, each response average was divided by the recording's overall amplitude. For the central 4 degrees this ratio increased by 0.18 (p = 0.002) for N1P1 and by 0.27 (p < 0.001) for P1N2. Clouding of the optic media such as produced by cataracts has a slight but significant influence on the multifocal ERG.

Aged↗
PubMed2004

Follow up in open angle glaucoma. A comparison of static perimetry and the fast stimulation mfERG. Multifocal ERG follow up in open angle glaucoma.

PURPOSE: To compare changes in the mfERG to visual field changes observed in OAG. METHODS: Twenty-nine eyes with OAG were included. Visual fields (Octopus d32) and mfERGs (VERIS) were obtained at a mean interval of 9 months (SD 6 months). MfERG recording parameters were as follows: 103 hexagons stimulated the central 50 degrees. M-sequence 2--5, stimulus base interval 13.33 ms, Lmax 200 cd/m2, contrast 99%. First (KI) and second (KII) order response components were analyzed for the individual quadrants of the visual field and compared to the corresponding mean deviation (MD) of the static perimetry. RESULTS: Changes in visual field parameters and changes in the mfERG did not differ significantly. Overall, as mean deviation increased there was a tendency for implicit times to increase and for amplitudes to decrease. However, over the follow up interval of 9 months only minor changes were observed. The second order response component correlated best with changes in MD (p < 0.05). These were the correlation between MD and KII N1 (r: 0.36) in the upper temporal field, between MD and KII N2 (r: 0.40) in the upper nasal field and between MD and KII P1 (r: 0.38) in the lower temporal field. When a subgroup of 10 eyes that had been tested at least 3 times over 16.8 months (SD 5.5) was examined there were still only minor changes observed in either parameter. CONCLUSION: While the changes over time in the mfERG and the visual field showed a reasonable correlation, changes observed in either parameter were extremely small over the time period observed, thus requiring a longer follow up and/or a more sensitive stimulation technique.

Electroretinography↗
PubMed2003

Malignant glaucoma due to drug-related angioedema.

PURPOSE: To report postsurgery angioedema resulting in malignant glaucoma. Interventional case report. METHODS: Three hours after uncomplicated cataract surgery on the right eye, a 61-year-old woman developed angioedema with swelling of the parapharyngeal tissue. Visual acuity deteriorated, and tonometry revealed an intraocular pressure of 60 mm Hg, with shallow anterior chambers, in both eyes. RESULTS: Ultrasound showed choroidal effusion on both eyes. Intraocular pressure could only be controlled surgically by procedure to deepen the anterior chamber. The angioedema regressed after withdrawal of candesartan, an angiotensin II antagonist that the patient had taken for 1 year. CONCLUSIONS: Angioedema without urticaria is well documented in patients receiving angiotensine-converting enzyme inhibitors or angiotensin II antagonists. Drug-related angioedema may lead to a choroidal effusion syndrome with malignant glaucoma. Surgical intervention may trigger angioedema. Most important in treatment is withdrawal from the implicated medication and control of intraocular pressure.

Angioedema↗
PubMed2003

Detection of retinal dysfunction in vitelliform macular dystrophy using the multifocal ERG (MF-ERG).

Vitelliform macular dystrophy (VMD) is widely known for an abnormal EOG in the presence of a normal ERG. In this study the multifocal electroretinogram (MF-ERG) is described as an additional tool to detect retinal dysfunction in VMD. Three patients aged 30, 37 and 59 years with VMD and a visual acuity of OD: 0.4; OS 0.05 (patient 1), 1.25 OU (patient 2) and OU: 0.6 (patient 3) underwent additional electrophysiological testing with the MF-ERG. A multifocal-ERG of the central 50 degrees of the retina was obtained using the VERIS-system. During recording 103 hexagons flickered according to a binary m-sequence of 2(15). Mean luminance was 100 cd/m2, contrast was set at 99%. The MF-ERG recordings were compared to age matched control groups. In all three patients the MF-ERG of the central 6 degrees showed reduced amplitudes for N1P1 (first negative peak to first positive peak) and for P1N2 (P1 to the second negative peak). Implicit times were not affected. Therefore the MF-ERG can detect focal retinal dysfunction in VMD which would not be apparent in the summed retinal response recorded with the ganzfeld ERG. In contrast to other diseases, amplitudes rather than implicit times seem to be affected in the MF-ERG of vitelliform macular dystrophy.

Adult↗
PubMed2003

[Anatomical differences in optic nerve, chiasma and tractus opticus in human albinism as demonstrated by standardised clinical and MRI evaluation].

BACKGROUND: There has been long-standing clinical and electrophysiological evidence that in patients with albinism the visual pathways cross atypically: most fibres from one eye cross to the contralateral visual cortex. PURPOSE OF THE STUDY: to determine whether the size and configuration of the optic chiasm in human albinos is different from normally pigmented controls. PATIENTS AND METHODS: 17 patients (11 female, mean age 35.8 years) with oculocutaneous albinism underwent a standardised graded morphological and functional evaluation. Magnetic resonance images were reformatted to the region of the optic chiasm and analysed using observer-independent morphometry. In addition, fMRI of the visual cortex was performed during VEP analysis (1.5 Tesla Siemens Vision). Morphological and fMRT results were compared to an age-correlated group of n = 16 normally pigmented healthy volunteers with normal visual acuity and stereopsis. RESULTS: 65 % of the patients (n = 10) showed signs of dysplasia of the optic nerve head. Statistical morphometry showed distinct differences in chiasmal morphology between albinos and normally pigmented probands (smaller optic nerves, different angles of optical entry into the chiasm and of the beginning of the Tractus optici leaving the chiasm, overall chiasmal width and height). CONCLUSIONS: Optic nerve head anomalies are frequent in albinism and influence visual outcome. Size and configuration of the optic chiasm in human albinos is distinctly different from normally pigmented control persons and reflects the atypical crossing of optic fibres.

Adult↗
PubMed2003

[First steps with the Zeiss IOLMaster: A comparison between acoustic contact biometry and non-contact optical biometry].

BACKGROUND: After having received an IOL-Master (Zeiss, Jena), we compared our actual standard method with this new device. PATIENTS, MATERIALS AND METHODS: From March to June 2002, we examined 175 consecutive cataractous eyes with the IOL-Master as well as with the acoustic biometry (Tomey AL-1000) combined to the Javal-Keratometer (Haag-Streit, Bern). The results were compared and analysed statistically. In all eyes, the intraocular lens to be implanted was chosen by means of the SRK/T formula, based on the measurements conducted with our standard method. The achieved postoperative refraction of 153 eyes obtained, at least six weeks after surgery, by the treating ophthalmologists, was communicated to us. RESULTS: Comparison of eye lengths as well as of the keratometric measurements showed good correspondence between the obtained measurements by both methods, acoustic biometry yielding significantly (p < 0.001) shorter axial lengths than the IOL-Master, and the Javal yielding significantly (p < 0.001) higher mean corneal refraction power than the IOL-Master. For both measurements, regression lines showed good coherence of the results over the refraction sample of our patients. Surprisingly, the accuracy of the refraction obtained postoperatively compared to the preoperative aim was better with our standard method compared to the IOL-Master. CONCLUSIONS: The predicted systemic differences in measurement results could be verified. No improvement in accuracy of our postoperative refraction prediction was achieved so far. The current advantage of the IOL-Master in our clinic is the substantial gain in time, as well as the fact that performance of the measurements may be delegated.

Adult↗
PubMed2003

[Prevalence of optic atrophy and associated ocular and systemic diseases in a department of paediatric ophthalmology].

BACKGROUND: Optic atrophy is one of the most common causes of severe visual impairment in children. So far an analysis of ocular and systemic findings comparing patients with and without optic atrophy has not performed. PATIENTS AND METHODS: Ocular and systemic findings of a total of 1042 patients (examination of all patients in May 1995 [N = 485] and May 2001 [N = 557]) of the department of paediatric ophthalmology in Homburg/Saar were retrospectively evaluated and diagnoses of patients with and without optic atrophy were compared. Optic atrophy was diagnosed ophthalmoscopically and in 1/3rd of the patients by VEP as well. RESULTS: 18 % of all patients (N = 188; 87.2 % [N = 164] were children) had optic atrophy. Nearly half of these children were prematurely born (46.7 %). 53.2 % of patients with optic atrophy (N = 88) showed nystagmus (without atrophy: 10.7 %), especially sensory defect nystagmus. Median of visual acuity level was 0.2 with optic atrophy and 0.8 without. Albinism and buphthalmia were common findings. 69.5 % of all patients with optic atrophy suffered from systemic diseases (without atrophy: 25.2 %), especially mental retardation, neurologic findings and oculocutaneous albinism. In 10.4 % more than two systemic diagnoses could be found. 55.3 % of all the patients with optic atrophy were disabled, 31.9 % multiply disabled. CONCLUSIONS: Sequelae of prematurity, peripartal asphyxia and congenital brain damages are the main findings in patients with optic nerve atrophy. Such children are worst-case patients of any paediatric ophthalmology department with a high prevalence of severe visual impairment, mental retardation and multiple disability. Treatment in a specialised center is therefore necessary for an efficient therapy. In addition, the statistical survey shows that in children who survived the critical phases of prematurity secondary damages can lead to persistent impairment and to alterations of visual and general development.

Adolescent↗
PubMed2002

Influence of photodynamic therapy in choroidal neovascularization on focal retinal function assessed with the multifocal electroretinogram and perimetry.

PURPOSE: To study the influence of photodynamic therapy (PDT) on retinal function in patients with a predominantly classic choroidal neovascular membrane. DESIGN: Comparative observational study. PARTICIPANTS: Sixteen eyes with a choroidal neovascular membrane eligible for PDT were included. METHODS: Visual acuity, multifocal electroretinogram (MF-ERG, Electrodiagnostic Imaging, San Mateo, CA) recordings and visual fields (Octopus d32) were obtained before PDT with Visudyne, Novartis AG, Basel, Switzerland, and at follow-up 2 weeks to 3 months later. MAIN OUTCOME MEASURES: Visual acuity as well as peak-to-peak amplitudes, peak latencies, and focal differences in the scalar product of the two MF-ERG recordings were analyzed. Mean deviation, loss variance, and the absolute difference in sensitivity in the fields obtained were also analyzed. RESULTS: After PDT, mean visual acuity stabilized or improved in 13 eyes. Except for two eyes with a predominantly parafoveolar choroidal neovascular membrane, the MF-ERG contribution from the central 4 degrees was reduced below the normal level. Although it improved slightly after PDT, it remained below the normal range. In the central 7.5 degrees, retinal sensitivity increased by up to 80 dB and within the paracentral 7.5 degrees to 15 degrees, it increased by up to 183 dB in 13 eyes. CONCLUSIONS: Consistent with the results of the treatment of age-related macular degeneration with photodynamic therapy (TAP) study, PDT can lead to stabilization of visual acuity. Improvement in parafoveal function can be demonstrated in the central visual field, as well as in MF-ERG recordings, even in patients whose visual acuity remains stable. Therefore, the MF-ERG and central perimetry may aid the assessment of retinal function in treatment trials of patients with age-related macular degeneration.

Choroidal Neovascularization↗
PubMed2002

[Thrombotic thrombocytopenic purpura (Moschcowitz's disease)].

BACKGROUND: TTP is a rare haematological disease consisting of thrombocytopenia, haemolytic anaemia, fever, neurological symptoms and renal failure. PATIENT: A 63-year-old female patient presented to our clinic with bilateral progressive loss of visual acuity accompanied by metamorphopsia. Ophthalmoscopy revealed pigmentepithelial choroidal atrophy secondary to the occlusion of chorioidal vessels and disseminated intraretinal and diffuse vitreal haemorrhage. Fluorescein angiography showed an obvious hyperfluorescence in the areas of choroidal atrophy as well as perivascular leakage. The patient had a history of TTP, as diagnosed by internal medicine. CONCLUSION: Vascular damage in TTP is due to disseminated hyalin clots of fibrin platelets which aggregate in the small capillaries, caused by a disorder of the endothelium-thrombocyte interaction. When evaluating patients with occlusion areas of the choriocapillaris, Moschcowitz's disease should be taken into consideration even in elderly patients.

Atrophy↗
PubMedDate not supplied

Management and results of retinal detachment after silicone oil removal.

Of the 168 eyes undergoing silicone oil removal from 1993 to 2000, 34 developed retinal detachment after the removal of silicone oil. The management and the results of the 34 eyes were reviewed. Surgical procedures included pars plana vitrectomy, encircling band, cryocoagulation, endotamponade. Five of the 34 eyes had a second retinal detachment after these operations. One of these 5 eyes had a third retinal detachment. Final retinal reattachment was achieved in all eyes. Visual acuity decreased in 16 of the 34 eyes with retinal detachment, and 18 of the 34 eyes had a visual acuity of less than 0.02. These results show that surgery for retinal detachment after silicone oil removal yields a high rate of anatomic success, while the visual outcome is poor for a substantial number of patients.

Adult↗