Biomedical subjects

P Martus

Publications and source records attributed to P Martus.

At least 55 records · Page 3Linked to original sources

PubMed2001

A measurement model of disease severity in absence of a gold standard.

In the absence of a gold standard, we propose the use of confirmatory factor analysis for the quantification of agreement between diagnostic measurements and the true disease severity. The essential assumption is conditional independence of diagnostic measurements adjusted for the severity of the disease. However, depending on the number of measurements available, the method works even if some of them are conditionally dependent. We illustrate the method using an example related to glaucoma eye disease.

Case-Control Studies↗

PubMed2000

Squamous cell carcinoma of the oropharynx: Ki-67 and p53 can identify patients at high risk for local recurrence after surgery and postoperative radiotherapy.

PURPOSE: To assess the prognostic value of biologic (p53, Ki-67) and clinical factors in squamous cell carcinoma of the oropharynx after radical surgery and postoperative radiotherapy (RT). METHODS AND MATERIALS: Between 1985 and 1995, a total of 102 patients with 104 tumor sites were entered onto the study. Fifty-five primary tumors (53%) involved the tonsils, 26 (25%) the soft palate, and 23 (22%) the base of the tongue. Median age was 53 years (range 36-80 years). The clinical T- and N-categories (UICC 1997) were: T1 (30), T2 (47), T3 (22), T4 (5), N0 (33), N1 (28), N2 (42), and N3 (1). Histologically-clear margins were achieved in all patients by initial surgery. Postoperative RT to the primary and regional lymphatics was given, to a total of 60 Gy in 6 weeks, and single daily fractions of 2 Gy. The expression of the nuclear p53- and Ki-67-labeling index (LI) was investigated by immunostaining using the monoclonal antibodies DO-7 and MIB 1. The nuclear p53-intensity (p53-I) was graded into 4 categories (0/+/++/) by densitometry. Median follow-up was 43 months (range 14-132 months). RESULTS: Cancer-specific survival, disease-free survival, and locoregional tumor control rates were 74%, 69%, and 75%, respectively, at 5 years. Significant prognostic factors for disease-free survival were: T-category (T1/2: 77% vs. T3/4: 53%, p = 0.02), tumor site (tonsils: 79% vs. soft palate: 70% vs. base of tongue: 45%, p = 0.05), duration of RT (< or = 46 days: 80% vs. > 46 days: 60%, p = 0.04), Ki-67 LI (< or = 20%: 84% vs. > 20%: 49%, p = 0.006) and p53-I (0/+: 56% vs. ++/ : 79%, p = 0.008). A significant prognostic impact on locoregional control was noted for the duration of RT (< or = 46 days: 86% vs. > 46 days: 68%, p = 0.01), tumor site (tonsils: 88% vs. soft palate: 67% vs. base of tongue: 51%, p = 0.02), Ki-67 LI (< or = 20% LI: 87% vs. > 20% LI: 56%, p = 0.018), and the p53-I (0/+: 58% vs. ++/ : 88%, p = 0.0006). On multivariate analysis, the p53 nuclear intensity (p = 0.002) and the Ki-67 index (p = 0.01) remained the only significant factors for locoregional control. CONCLUSION: Ki-67 labeling index above 20% and a weak p53 nuclear intensity (0/+) are both able to identify patients with squamous cell carcinoma of the oropharynx being at high risk for local recurrence after surgery and postoperative RT. Consequently, in this subgroup an intensification of treatment may be contemplated in prospective trials.

Adult↗

PubMed2000

Apoptosis, p53, bcl-2, and Ki-67 in invasive bladder carcinoma: possible predictors for response to radiochemotherapy and successful bladder preservation.

PURPOSE: Several groups have reported the value of bladder preservation by a combined treatment protocol, including transurethral resection (TUR-B) and radiochemotherapy (RCT). As more experience is acquired with organ-sparing treatment, patient selection should be optimized. The purpose of this study was to investigate the role of several biologic markers that may predict response to RCT in muscle-invasive bladder carcinoma. METHODS AND MATERIALS: The apoptotic index (AI), Ki-67, p53, and bcl-2 were evaluated by immunohistochemistry on pretreatment biopsies from 70 patients treated for invasive bladder cancer by TUR-B and RCT. Expression of each marker was correlated with initial response, local control, and cancer-specific survival with preserved bladder. An exploratory multivariate analysis was also performed that included clinical and immunohistochemical variables. RESULTS: A high AI (> median = 1.6%) and a high Ki-67 index (> median = 8.8%), but not the p53- and bcl-2 expression, were significantly related to initial complete response (CR) and local control with preserved bladder after 5 years. When the AI and Ki-67 expression were considered simultaneously, the association with initial CR (p < 0. 001), local control (p = 0.0002), and cancer-specific survival with preserved bladder (p = 0.008) was highly significant. In an exploratory multivariate analysis (final model), only AI, Ki-67, and the combined AI/Ki-67 variable retained significance for local control with preserved bladder at 5 years. CONCLUSION: Patients with a high spontaneous AI and a high pretreatment Ki-67 index should be considered preferentially for treatment with RCT, whereas tumors with low proliferation and low levels of apoptosis are less likely to respond to RCT.

Aged↗

PubMed2000

Statistical methods for the evaluation of diagnostic measurements concerning paired organs.

Diagnostic measurements involving paired organs may be modelled using marginal or conditional approaches. Relevant information could be ignored by using marginal models with a mean structure not including information from the fellow organ. The conditional Rosner model can be generalized to a symmetric polychotomous logistic regression model. The rather strong assumptions of the Rosner model are relaxed in this symmetric model. The use of the symmetric model is justified by its relation to discriminant analysis. Additionally, the information of the diagnostic measurements from the fellow organ is taken into account explicitly. Furthermore, in case-control studies this approach corresponds to the sampling scheme. When the status of the fellow organ and the diagnostic measurement of this organ both are available, a surprising effect may be observed; pathological values of the diagnostic measurement from the fellow organ decrease the disease probability of the selected organ. As an example, four different diagnostic procedures from the Erlangen Glaucoma Registry are investigated.

Contrast Sensitivity↗

PubMed2000

Clinical evaluation of contrast-enhanced color Doppler sonography in the differential diagnosis of liver tumors.

PURPOSE: We investigated the value of contrast-enhanced color Doppler sonography in the differential diagnosis of liver tumors. METHODS: We prospectively examined 105 focal liver lesions in 100 patients by real-time gray-scale sonography, color Doppler sonography, and contrast-enhanced color Doppler sonography with galactose-based microbubbles (SH U 508A; Levovist). The final diagnoses of the liver lesions as confirmed by pathology or additional imaging techniques were 31 metastases, 25 hemangiomas, 19 hepatocellular carcinomas, 19 focal nodular hyperplasias, 2 cholangiocellular carcinomas, and 9 other lesions. RESULTS: Vascularity could be detected in 43 (41%) of the 105 lesions by conventional color Doppler sonography compared to 67 (64%) by contrast-enhanced color Doppler sonography. Contrast-enhanced color Doppler sonography identified moderate or extensive vascularity in all 19 focal nodular hyperplasias, moderate or extensive vascularity in 16 hepatocellular carcinomas and both cholangiocellular carcinomas, and no or minor vascularity in all but 3 hemangioma. The combination of gray-scale, conventional color Doppler, and contrast-enhanced color Doppler sonography led to the correct diagnosis in 81% of cases (85 of 105), compared to 57% (60/105) for gray-scale and conventional color Doppler sonography and 31% (33/105) for gray-scale sonography alone. CONCLUSIONS: Contrast-enhanced color Doppler sonography improves the detection of tumor vascularity and is useful in the differential diagnosis of liver lesions.

Confidence Intervals↗

PubMed2000

Extensive surgery after high-dose preoperative chemoradiotherapy for locally advanced recurrent rectal cancer.

PURPOSE: This was a pilot study of high-dose preoperative concurrent radiation and chemotherapy before extensive surgery in patients with locally advanced recurrent rectal cancer. Here we report on curative resectability, acute toxicities during chemoradiotherapy, surgical complications, local control, and three-year survival rates achieved with this aggressive multimodal regimen. METHODS: Between 1994 and 1997, 35 previously nonirradiated patients with pelvic recurrence of rectal cancer were entered in the study. All patients presented with tumor contiguous or adherent to adjacent pelvic organs and were not deemed amenable to primary curative surgery. A total radiation dose of 50.4 Gy with a small-volume boost of 5.4 to 9 Gy was delivered in conventional fractionation (single dose, 1.8 Gy). 5-Fluorouracil was scheduled as a continuous infusion of 1,000 mg/m2/day on Days 1 to 5 and 29 to 33. Six weeks after completion of chemoradiotherapy, patients were reassessed for resectability, and radical surgery was attempted whenever feasible. RESULTS: After preoperative chemoradiotherapy 28 of 35 patients (80 percent) underwent resection with curative intent. In 16 of 35 patients (57 percent) extended resection of adjacent organs was performed. Resections with negative margins were achieved in 17 patients (61 percent); 9 patients had microscopic, and 2 patients had gross residual disease. There was no postoperative mortality. Fourteen patients (44 percent) experienced postoperative complications. Toxicity from chemoradiotherapy occurred mainly as diarrhea (National Cancer Institute Common Toxicity Criteria Grade 3; 23 percent), dermatitis (Grade 3; 11 percent), and leucopenia (Grade 3; 11 percent). One patient died of tumortoxic multiple organ failure during chemoradiotherapy. With a median follow-up of 27 months, local re-recurrence after curative resection was observed in only three patients (18 percent); six patients developed distant metastases. Three-year actuarial survival rate was significantly improved after complete resection (82 percent) as compared with noncurative surgery (38 percent; P = 0.03). CONCLUSION: A combination of high-dose preoperative chemoradiotherapy followed by extended surgery can achieve clear resection margins in more than 60 percent of patients with recurrent rectal tumor not amenable to primary surgery. An encouraging trend evolved for this multimodal treatment to improve long-term local control and survival rate.

Adult↗

PubMed2000

Quantitative analysis of visual field and optic disk in glaucoma: retinal nerve fiber bundle-associated analysis.

BACKGROUND: A study was performed to evaluate whether visual field analysis using a perimetric nerve fiber bundle map gives information additional to global visual field indices and cumulative defect curves for early glaucoma diagnosis. METHODS: One hundred and four control subjects, 124 patients with ocular hypertension (OHT), 97 patients with high-tension glaucoma without visual field defects (preHTG) and 91 patients with open-angle glaucoma with visual field defects [30 low-tension glaucoma (LTG), 61 high-tension glaucoma (HTG)] were included in this study. Correlation analyses were performed between (a) global visual field indices and total neuroretinal rim (NRR) area; (b) local mean values of four visual field areas and the NRR area of the corresponding four optic disk sectors; and (c) local mean values of 10 perimetric nerve fiber bundles (PNFB 1-10) according to Weber and Ulrich (1991) and the four optic disk sectors. The correlations were adjusted for global mean defect and total NRR. RESULTS: There were no significant correlations between NRR area and visual field in control subjects or in patients with OHT or preHTG for all three analyses. Significant correlations were found between the global visual field indices and the total NRR area for LTG and HTG. Significant correlations between local mean defects and NRR area of corresponding optic disk sectors were found only in LTG for the superior and inferior visual field area and the PNFB covering these areas. CONCLUSION: The method used for visual field analysis and sectorization of the optic disk does not give additional information on visual field defects in patients with normal global visual field indices and a normal cumulative defect curve. The nerve fiber bundle-related visual field analysis allows the topographical determination and quantification of glaucomatous damage.

Adult↗

PubMed2000

The full-field temporal contrast sensitivity test for glaucoma: influence of cataract.

PURPOSE: To determine the influence of lens opacities on temporal contrast sensitivity, measured by the full-field flicker test ("Erlangen flicker test"). METHODS: Thirty-six consecutive patients (mean age 71.1+/-11.6 years, 12 male, 24 female, refractive error -1.5+/-3.8 dpt) with cataract (visual acuity 0.21+/-0.16, retinal acuity 0.56+/-0.32, no glaucoma) were studied. Temporal contrast sensitivity (full-field flicker test, 37.1 Hz) and lens opacity (back scatter Lens Opacity Meter, Interzeag) were measured preoperatively and on the 3rd postoperative day. STATISTICS: nonparametric tests (Wilcoxon-test, Spearman correlation coefficient, Mann-Whitney U-test). RESULTS: No significant difference was seen in temporal contrast sensitivity pre- and postoperatively, but there was a significant difference in lens opacity measurements pre- and postoperatively. No significant correlation was found between temporal contrast sensitivity and lens opacity values preoperatively and postoperatively. CONCLUSION: The temporal contrast sensitivity, measured by the full-field flicker test, seems to be independent of lens opacity due to the range of cataract included in this study. The data indicate that the full-field flicker test is useful for early glaucoma detection even in patients with cataract formations.

Aged↗

PubMed2000

[Outcome quality of treatment for chronic low back pain under primary care conditions].

BACKGROUND: Little is known about the outcome quality of treatment for chronic low back pain under primary care conditions in Germany. METHODS: All physicians (2100) of middle Franconia, a region of Bavaria with 1.6 million inhabitants, involved in outpatient management were asked to include consecutively patients who suffered from low back pain of at least 4 weeks duration without decreasing intensity. Before and after a 6-month interval patients documented the following outcome data in a questionnaire: pain intensity during the last 24 hours (numerical rating scale), pain-dependent disability (Brief Pain Inventory, German version), health-related quality of life (SF-36, German version), depression (Allgemeine Depressionsskala), pain chronification state (Mainz Pain Staging System) and the days of inability to work within 3 months before start and end of the interval. Treatment of patients was not standardized and included the natural spectrum of non-surgical therapies for low back pain except multimodal pain therapy programs. RESULTS: Thirty-five physicians participated in the study. "Before and after" data of 157 patients (43+/-12 years) could be analysed. Initially 20% were classified in pain chronification state I, 57% in state II and 23% in state III. The pain intensity, pain-dependent disability, depression and quality of life improved significantly but mean differences and effect sizes were small (p<0.41). Less than one third of patients improved by 30% or more from baseline or by one step in the chronification state of pain. Days off work did not change significantly. Predictors for positive therapy response could not be identified. CONCLUSIONS: Monodisciplinary treatment procedures are not sufficient to ameliorate problems of patients in advanced chronification states of back pain.

English Abstract↗

PubMed2000

[Outcome-quality of treatment for headache on primary care conditions].

BACKGROUND: Little is known about the outcome-quality of treatment for headache on primary care conditions in Germany. METHODS: All physicians (2100) of middle franconia, a bavarian greater district with 1,6 Mio. inhabitants, involved in outpatient management were asked to include consecutively patients in the study which suffer from migraine (at least 2 attacks/month) and/or tension type headache (at least 8 days/month) of at least 4 weeks duration. Before and after a 6 months interval patients documented the following outcome data in a questionnaire: pain intensity during the last attack (numeric rating scale), pain dependent disability (Brief Pain Inventory, German version), health related quality of life (SF-36, German version) and depressivity (Allgemeine Depressionsskala). The pain chronification state (Mainz Pain Staging System) has been assessed by the physician. Therapy was not standardized and included the natural spectrum of medicamental and non-medicamental therapy of headache. Agreement of therapy with recommendations of the "Arzneimittelkommission der Deutschen Aerzteschaft" has been assessed. RESULTS: 24 physicians participated in the study. Pre-post-data of 80 patients (46+/-14 y) could be analysed. Initially 67% were classified in pain chronification state I, 27% in state II and 6% in state III. Medicamental therapy agreed with recommendations in approximately 50% of patients, non-medicamental therapy has been used rarely. The pain intensity, pain dependent disability, depression and quality of life improved significantly. 45% and 55% of patients improved in at least 2 of 6 outcome-parameters by 30% of baseline value or by half standard deviation of the corresponding pre-post-differences, respectively. The latter outcome-measure reflects a medium effect size. CONCLUSIONS: On primary care conditions about 50% of patients suffering from migraine and/or tension type headache (predominantly low chronification stae) perceive a therapy effect that corresponds to a medium effect size.

English Abstract↗

PubMed2000

Migraine and tension headache in high-pressure and normal-pressure glaucoma.

PURPOSE: To analyze the association of normal-pressure glaucoma and migraine. METHODS: In a prospective study, 154 patients with glaucoma (56 normal-pressure subgroup and 98 high-pressure glaucoma subgroup), 55 patients with ocular hypertension, and 75 control subjects were analyzed by means of a standardized questionnaire based on International Headache Society criteria. RESULTS: According to the questionnaire, 46 patients (17%) were classified as suffering from migraine and 20 (7%) from tension headache (episodic and chronic). The prevalence of headache, migraine, and tension headache did not vary significantly among control subjects, patients with ocular hypertension, and patients with glaucoma, but migraine was significantly more common in patients with normal-pressure glaucoma (28%) compared with control subjects (12%; P<.05) and patients with high-pressure glaucoma (10%; P<.01). CONCLUSION: The results suggest an association of normal-pressure glaucoma and migraine and a potential, common vascular etiology of both diseases.

Adolescent↗

PubMed2000

Anterior chamber depth and complications during cataract surgery in eyes with pseudoexfoliation syndrome.

PURPOSE: To look for associations of preoperative A-scan ultrasound ocular dimensions with complications during phacoemulsification in eyes with pseudoexfoliation. METHODS: A total of 174 eyes with pseudoexfoliation of 135 patients undergoing planned cataract surgery were included in a prognostic study based on the review of a clinical database. Preoperatively, A-scan ultrasound examination with measurement of anterior chamber depth, lens thickness, and total axial length was performed. Phacoemulsification with implantation of a posterior chamber intraocular lens was performed by a total of five surgeons. Intraoperative complications (zonular dialysis and/or vitreous loss) were correlated with preoperative findings including ultrasound dimensions. Multivariate logistic regression analysis with a generalized estimating equations method was used for statistical analysis. RESULTS: Intraoperative complications occurred in 12 eyes (6.9%) of 11 patients. The anterior chamber was significantly shallower in eyes with than in eyes without complications (mean, 2.36 +/- 0.44 mm vs 2.74 +/- 0.52 mm; P =.013). The differences in lens thickness (4.93 +/- 0.55 mm vs 4.72 +/- 0.54 mm; P =.30) and the differences in axial length (22.92 +/- 1.09 mm vs 23.66 +/- 1.36 mm; P =.07) between the two groups did not reach statistical significance. In eyes with pseudoexfoliation, an anterior chamber depth of less than 2.5 mm was associated with a risk of 13.4% for intraoperative complications compared with an overall incidence of intraoperative complications of 6.9% and an incidence of 2.8% for an anterior chamber depth of 2.5 mm or more. CONCLUSIONS: A small anterior chamber depth may indicate zonular instability in eyes with pseudoexfoliation syndrome and should alert the cataract surgeon to the possibility of intraoperative complications.

Aged↗

PubMed2000

Quantification of aqueous melanin granules, intraocular pressure and glaucomatous damage in primary pigment dispersion syndrome.

OBJECTIVE: Aqueous melanin granules may be accurately quantified with the laser flare-cell meter and have been demonstrated to be increased in primary pigment dispersion syndrome (PDS). It was the aim of this study to correlate intraocular pressure, glaucomatous damage of the optic nerve head, and visual field defects with the number of aqueous melanin granules in PDS. DESIGN: Cross-sectional study. PARTICIPANTS: Thirty-nine eyes of 21 patients with PDS and either ocular hypertension or pigmentary glaucoma. MAIN OUTCOME MEASURES: A 24-hour intraocular pressure (IOP) profile, automated perimetry (Octopus G1), and analysis of photostereographs and HRT (Heidelberg Retina Tomograph) images of the optic disc were performed. Aqueous melanin granules were quantified using the cell count mode of the laser flare-cell meter (KOWA FC-1000) with undilated and dilated pupils. Granule counts were correlated with maximum and mean IOP, maximum range (amplitude) of IOP, mean defect of automated perimetry (G1-program), and damage to the optic disc was measured with the HRT. RESULTS: The number of aqueous melanin granules showed a strong correlation with maximum IOP in both undilated (r = 0.72, P < 0.001) and dilated eyes (r = 0.5, P = 0.02). A marginal correlation was found with the IOP range (r = 0.43, P = 0.04) and the mean defect of automated perimetry (r = 0.41, P = 0.06) in undilated eyes. The mean IOP and HRT measurements of the optic disc (area, volume of the neuroretinal rim, third moment in contour) showed no statistically significant correlation with the number of aqueous melanin granules (r < 0.4, P > 0.2). CONCLUSIONS: A larger number of aqueous melanin granules is strongly associated with high IOP and also with visual field loss, providing additional evidence of the relation between aqueous melanin dispersion and development of pigmentary glaucoma. Quantification of aqueous melanin granules with the laser flare-cell meter might be useful for evaluation of treatment effects, including laser iridotomy, in patients with PDS.

Adult↗

PubMed2000

Evaluation of neuronal effects of electroconvulsive therapy by magnetoencephalography (MEG).

1. Interictal spontaneous MEG was investigated in five male patients with major depressive disorder (according to DSM IV) treated with right hemispheric ECT over a period of five weeks. Spontaneous MEG-activity was also recorded in five male patients treated with tricyclic antidepressants during the same time period. 2. The analysis of slow (0-7Hz) and fast (12.5-30Hz) MEG activity was done with the dipole density plot, which uses consecutively estimated dipoles across a given analyzing time and delivers quantified dipole concentrations in three dimensions 3. In the ECT group the authors found a significant increase in the dipole concentration in the slow activity range (0-7Hz) after the first and the subsequent treatments, which could not be found in patients treated with tricyclic antidepressants. The localisation of the dipoles showed an "anteriorposterior"--gradient with a maximum concentration in the frontal and temporal region. 4. In the fast activity range (12.5-30Hz) the ECT group differed from the control group by a significant decrease of dipole activity, which was concentrated in the temporal and parietal region. 5. These results in part confirm interictal EEG findings after right hemispheric ECT and also lend strong support to ECT-effects in the fast activity ranges.

Adult↗

PubMed2000

[Interim results from the prospective "Erlanger Non-high-risk Penetrating Keratoplasty Study" in 207 patients].

BACKGROUND: Immunologic graft rejection targeted against corneal endothelium is the most frequent cause for graft failure after corneal transplantation. The purpose of this prospective study was to assess the frequency, early symptoms, prophylaxis and therapy monitoring of corneal graft rejection following non-high-risk penetrating keratoplasty (PK). PATIENTS AND METHODS: From February 1997 to May 1999, 237 patients undergoing non-high-risk PK have been enrolled in this prospective study. We evaluated 207 patients (103 female, 113 right eyes, recipient age 54 +/- 20 years, donor age 59 +/- 17 years). In 2 randomized treatment studies we compared the efficacy of postoperative short-term (ST = 6 months) versus long-term (LT = 12 months) topical steroid therapy on the incidence of graft rejection and the effect of high- versus low-dose systemic steroid therapy on the prognosis after a graft rejection. Follow-up examinations included, laser-tyndallometry, corneal topography analysis, endothelial cell count and pachymetry. RESULTS: The main indications for PK were keratoconus (n = 93), endothelial dystrophy Fuchs (n = 52) and bullous keratopathy (n = 35). In 151 (73%) patients, non mechanical trephination with the 193 nm Excimer laser was performed. Up to now, 78 patients were randomized into two groups comparing the postoperative therapy with topical steroids. During follow-up (median: ST: 13.5 months; LT: 12.5 months, maximum 25.3 months) episodes of endothelial graft rejection (3 chronic focal, 8 acute diffuse) showed 11 eyes of 11 patients. Five patients each had short-term and long-term topical steroid treatment. In 1 patient the graft rejection occurred before randomization at 6 months. Six patients with graft rejection episodes underwent a PK only (54% of graft rejections, 4.4% of all patients). In the remaining 5 patients, PK was combined with a lens surgery (46% of graft rejections, 6.9% of all patients). Ten of 11 corneal grafts regained their full function under treatment with systemic and local steroids. CONCLUSION: The frequency of episodes of graft rejection in our study was lower than usually reported in the literature. A good compliance of patients appears to be a major factor for improved prognosis of the graft after PK and in case of graft rejection. Until now no significant differences between short-term or long-term postoperative topical steroid therapy could be detected regarding the incidence of corneal graft rejection.

Administration, Oral↗

PubMed2000

[Synopsis of various electrophysiological tests in early glaucoma diagnosis--temporal and spatiotemporal contrast sensitivity, light- and color-contrast pattern-reversal electroretinogram, blue-yellow VEP].

BACKGROUND: Of the three glaucoma-defining criteria intraocular pressure, optic-nerve damage, and visual field damage, the latter is a late symptom. Therefore, in order to improve an early sensory diagnosis, new tests are necessary. It is the aim of the present paper to test new sensory methods, to rank them in an order of sensitivity, and to base them on possible pathophysiological mechanisms. PATIENTS AND METHODS: The tests were carried out in subjects of the Erlangen Glaucoma registry: Normals, patients with ocular hypertension, and patients with open-angle glaucoma without or with field defects. The tests are designed to preferentially probe the function of different groups of ganglion cells. Psychophysical methods: Temporal contrast sensitivity in a ganzfeld as "Erlangen flicker test" and spatio-temporal contrast sensitivity to test Magno-cell function. Electrophysiological methods: Pattern-reversal electroretinogram with a luminance-contrast pattern to test Magno-cell function, color-contrast pattern electroretinogram for Parvo-cell function, and blue-on-yellow visual evoked potential to test the "blue-sensitive" pathway. RESULTS: The most sensitive test is the temp.CS, it is significantly reduced in OHT (p < 0.01). The spatio-temp.CS is reduced in perimetric stages (p < 0.01). The BY-VEP is altered in the preperimetric stage (p < 0.01), the PR-ERG in perimetric stages (p < 0.01). The CC-ERG is reduced in even later stages. These results are in agreement with the hypothesis that tests selective for non-redundant neurons are of early diagnostic value. Multivariate analyses increase the early diagnostic value when different functions are tested in combination. CONCLUSIONS: When a particular test is taylored to the the special needs of certain groups of ganglion cells sensory defects can be observed before the occurrence of optic-nerve damage (OHT). The most sensitive psychophysical test is the "Erlangen flicker test" which is a screening test selective for M cells. The most sensitive electrophysiological test is the BY-VEP testing the blue-sensitive ganglion cells.

Color Perception↗

PubMed2000

Analysis of the risk factors associated with endoscopic sphincterotomy techniques: preliminary results of a prospective study, with emphasis on the reduced risk of acute pancreatitis with low-dose anticoagulation treatment.

BACKGROUND AND STUDY AIMS: The aim of the present study was to analyze the risk factors associated with complications of endoscopic sphincterotomy (ES). PATIENTS AND METHODS: In all consecutive endoscopic sphincterotomies carried out between September 1994 and December 1996, the possible risk factors (12 patient-related factors and 12 procedure-related ones), as well as the concomitant medical treatment, indications, techniques, and success of endoscopic sphincterotomy were evaluated prospectively. Risk factors were analyzed on an exploratory basis using univariate methods. "Potential risk factors" (univariate, P<0.1) underwent multivariate analysis to determine independent "risk factors" (multivariate, P<0.05). In addition, the complication rate was calculated according to the number of potential risk factors present. RESULTS: A total of 438 patients who underwent ES were analyzed. Complications occurred in 7.5% (n = 33; acute pancreatitis 4.3%, hemorrhage 2.3 %, cholangitis 0.9%, technical 0.2%). Statistical analysis of the complications identified three independent risk factors (coagulopathy, patient age (< or =60 years, pancreas divisum), and one protective factor (pancreatic duct obstruction). The frequency of acute pancreatitis was increased by two independent risk factors (pancreas divisum, ES frequency <40 procedures/year) and was reduced if low-dose anticoagulation (unfractionated heparin or low molecular weight heparin) was administered (0.9%, one of 115 vs. 5.8%, 18 of 313; P<0.05). The effect of anticoagulation was not confounded by the presence or absence of other potential risk factors for acute pancreatitis. Neither the risk nor the severity of hemorrhage were increased by low-dose anticoagulation. Due to the low number of events, only potential risk factors for hemorrhage were identified (coagulopathy, intensive-care treatment). The overall complication rate and the incidence of pancreatitis and hemorrhage increased significantly depending on the number of simultaneous potential risk factors present (P<0.0001). CONCLUSIONS: Patients at risk for complications after endoscopic sphincterotomy can be identified by risk factor analysis. These data suggest the hypothesis that low-dose anticoagulation prior to endoscopic sphincterotomy reduces the risk of acute pancreatitis after sphincterotomy.

Acute Disease↗

PubMed2000

Stimulus deprivation amblyopia in human congenital ptosis: a study of 100 patients.

AIM: To investigate the frequency of stimulus deprivation amblyopia (SDA) in comparison with other reasons for amblyopia in human congenital ptosis. METHODS: The frequency and causes of amblyopia were evaluated in the 200 eyes of 100 patients. Congenital ptosis was present in 128 eyes (72 unilateral, 28 bilateral). The age at investigation was one year and older, with an average of 11 years and 10 months. Amblyopia was defined as best corrected visual acuity less than 1.0 or a difference between the two eyes of at least 0.2. The following causes of amblyopia were identified: amblyopiogenic refractive errors: astigmatism > or = 1 dpt, anisometropia > or = 1 dpt (79% cycloplegia) and strabismus. In cases with no other reasons for amblyopia, SDA was assumed. Statistical analysis was performed using the chi-square and the sign tests. RESULTS: The overall incidence of amblyopia in ptotic eyes was 89/128 (70%). In 3.9% of the cases (5/128; 2 eyes with unilateral and 3 eyes with bilateral ptosis) we assumed SDA. A comparison of ptotic eyes with (unilateral: n = 35, bilateral: n = 34) and without covered optical axis revealed the following: in the case of unilateral ptosis, amblyopia was found more often in ptotic eyes with covered optical axis: 30 out of 35 vs. 24 out of 37 (p = 0.06); in the case of bilateral ptosis this difference was significant: 27 out of 34 vs. 8 out of 22 (p < 0.05). In the case of SDA, the optical axis was covered in only a single eye, in a patient with bilateral ptosis. There was no difference in the incidence of anisometropia: 19 out of 53 vs. 14 out of 47 (p = 0.52). Astigmatism was found more frequently in ptotic eyes with covered optical axis in unilateral ptosis: 23 out of 35 vs. 16 out of 37 (p = 0.06) but not in bilateral ptosis: 21 out of 34 vs. 13 out of 22 (p > 0.9). Strabismus was found significantly more frequently in ptotic eyes with covered optical axis: 13 out of 35 vs. 4 out of 37 (p < 0.05) in unilateral ptosis and 7 out of 34 vs. 1 out of 22 (p = 0.13) in bilateral ptosis. CONCLUSION: In contrast to the classical animal models of stimulus deprivation amblyopia, this entity is rare in human congenital ptosis, perhaps because of the counter effect of compensating head posture. Disruption of fusion resulting in strabismus might be an additional indirect cause of amblyopia in congenital ptosis. Prophylactic amblyopia treatment in ptosis cases is important as long as no testing of visual acuity is possible in a child.

Adolescent↗