Biomedical subjects

Frank Krummenauer

Publications and source records attributed to Frank Krummenauer.

At least 19 recordsLinked to original sources

PubMed2004

Chronic thromboembolic pulmonary hypertension: pre- and postoperative assessment with breath-hold MR imaging techniques.

PURPOSE: To evaluate the potential of breath-hold magnetic resonance (MR) imaging techniques in morphologic and functional assessment of patients with chronic thromboembolic pulmonary hypertension (CTEPH) before and after surgery. MATERIALS AND METHODS: Thirty-four patients with CTEPH were examined before and after pulmonary thromboendarterectomy (PTE). For morphologic assessment, contrast material-enhanced MR angiography was used; for assessment of hemodynamics, velocity-encoded gradient-echo sequences and cine gradient-echo sequences along the short axis of the heart were performed. Contrast-enhanced MR angiography was compared with selective digital subtraction angiography (DSA) for depiction of central thromboembolic material and visualization of the pulmonary arterial tree. Functional analysis included calculation of left and right ventricular ejection fractions and peak velocities, net forward volumes per heartbeat, and blood volume per minute in the left and right pulmonary arteries and ascending aorta. Flow measurements were compared with invasively measured mean pulmonary arterial pressure (MPAP) and pulmonary vascular resistance (PVR) measurements. Nonparametric Wilcoxon and sign tests were used for statistical analysis. RESULTS: MR angiography revealed typical findings of CTEPH (intraluminal webs and bands, vessel cutoffs, and organized central thromboemboli) in all patients. It depicted pulmonary vessels up to the segmental level in all cases. For subsegmental arteries, DSA revealed significantly more patent vessel segments than did MR angiography (733 versus 681 segments, P <.001). MR angiography revealed technical success of surgery in 33 of 34 patients. Patients had reduced right ventricular ejection fractions and pulmonary peak velocities that significantly increased after PTE (P <.001 for both). Right ventricular ejection fraction had good correlation with PVR (r = 0.6) and MPAP (r = 0.7). The postoperative decrease in MPAP correlated well with the increase in right ventricular ejection fraction (r = 0.8). Postoperatively, there was complete reduction of a preoperatively existing bronchosystemic shunt volume in 33 of 34 patients. CONCLUSION: Breath-hold MR imaging techniques enable morphologic and semiquantitative functional assessment of patients with CTEPH.

Adult↗

PubMed2004

MHC class I antigen processing pathway defects, ras mutations and disease stage in colorectal carcinoma.

Colorectal tumorigenesis has been associated with the progressive acquisition of a variety of genetic alterations. These include mutations of the Ki-ras proto-oncogene in codons 12 and 13, which account for 85% of genetic changes in colorectal cancer. In murine in vitro models of oncogenic transformation, an association between ras-mediated transformation and downregulation of different components of the MHC class I antigen processing machinery (APM) has been described. In order to investigate whether this association also exists in human tumors, 10 cases of high-grade intraepithelial neoplasia (HIN), as well as primary tumors and autologous lymph node metastases from 42 patients with colorectal carcinoma, were monitored by allele-specific restriction analysis for Ki-ras mutations. In parallel, APM component expression and tumor cell proliferation were analyzed by immunohistochemistry. In comparison to autologous colorectal mucosa, TAP1, LMP2 and tapasin loss was found in 68%, 67% and 80% of HIN, respectively. In contrast, impaired TAP1, LMP2 and tapasin expression was found in 42%, 42% and 63% of primary adenocarcinomas of stage III disease and in 63%, 47% and 79% of the matched lymph node metastases, respectively. More than 60% of colorectal tumor lesions with TAP1, LMP2 and/or tapasin defects displayed Ki-ras mutations. The frequency of TAP1, LMP2 and tapasin loss varied between 33% of primary adenocarcinomas, 40% of HIN to approximately 67% of metastases. These data suggest that i) APM component deficiencies occur more frequently in Ki-ras-mutated colorectal carcinoma lesions and ii) APM abnormalities in conjunction with Ki-ras mutations appear to be associated with disease stage. These findings support the hypothesis that Ki-ras mutations may contribute to immune escape mechanisms of tumors by downregulating the MHC class I APM component expression.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2004

Nonocclusion and early reopening of the great saphenous vein after endovenous laser treatment is fluence dependent.

BACKGROUND: Parameters influencing failure and recanalization rates of endovenous laser treatment (ELT) of the great saphenous vein (GSV) are still to be determined. OBJECTIVE: To evaluate treatment-related parameters of ELT with respect to early failure of occlusion or recanalization of GSVs. METHODS: A series of 77 consecutive patients received ELT of 106 GSVs with continuous pullback of the laser fiber. Duplex examination was performed at 1 day, 4 weeks, and 3 months after the procedure. Clinical patient and vessel characteristics as well as technical parameters of the ELT procedure were evaluated via multiple logistic regression analysis. RESULTS: A median vein length of 60 cm (range of 18 to 90) was treated with a median pullback velocity of 0.6 cm/sec (range of 0.4 to 1.3), resulting in a median energy delivery of 23.4 J/cm (range of 11.8 to 35.5) and a median laser fluence of 11.8 J/cm2 (range of 2.8 to 37.3). At day 1 after ELT, 6 GSVs (6%) were not occluded. At 1 and 3 months after ELT, 9 GSVs (9%) and 11 GSVs (10%), respectively, were found open by color duplex examination. Risk factors for nonocclusion 3 months after ELT, by univariate analysis, were laser fluence, laser energy per centimeter of vein length, diameter of the vein before treatment, and distance of the thrombus to the sapheno-femoral junction at day 1 after treatment. Finally, multiple regression analysis selected laser fluence (p=0.004, odds ratio=0.40 J/cm2) as the relevant risk factor for ELT failure or recanalization. CONCLUSION: ELT failure seems to be related to the administration of low laser fluences.

Adult↗

PubMed2004

Assessment of chronic aortic dissection: contribution of different ECG-gated breath-hold MRI techniques.

OBJECTIVE: Our objective was to evaluate the impact of different rapid MRI techniques for the assessment and follow-up of chronic aortic dissections. MATERIALS AND METHODS: Fifty-three patients (41 postoperative Stanford type A, 12 type B dissections) were scanned at 1.5 T during a 3-year period. The study reviewed ECG-gated breath-hold black blood sequences and 3D contrast-enhanced MR angiography of the thoracic aorta supplemented by segmented cine and phase-contrast imaging as well as abdominal contrast-enhanced MR angiography. A retrospective separate analysis of black blood acquisitions and contrast-enhanced MR angiograms from a total of 72 examinations was performed by two radiologists to evaluate detection of intimal flaps and assess image quality. RESULTS: Sensitivity and specificity of black blood sequences compared with those of contrast-enhanced MR angiography in detecting intimal flaps were 87% and 94% for the thoracic aorta, and 54% and 97% for the supraaortic branches, respectively. Contrast-enhanced MR angiography was subjectively rated as superior to black blood techniques for visualizing intimal flaps and yielded better overall image quality (p < 0.001). Aortic valve competence can be assessed on segmented cine techniques. Phase-contrast sequences enabled the quantification of regurgitant flow across the aortic valve and the analysis of flow patterns in the true and false channels. CONCLUSION: Contrast-enhanced MR angiography is superior to black blood MRI in detecting the presence or absence of intimal flaps and is particularly useful in assessing supraaortic branch vessel involvement. Cine and phase-contrast techniques should be included in the imaging follow-up to diagnose possible complications of chronic aortic dissections.

Adult↗

PubMed2003

Comparison of three different technologies for pupil diameter measurement.

BACKGROUND: The pupil diameter plays an important role in the occurrence of photopic phenomena after refractive surgery. Standardized estimation can be performed using a lens system with a built-in millimeter scale (Colvard, Oasis Medical, California). A new computerized technique allows dynamic and binocular measurement of the pupil diameter by use of infrared light (P2000SA, Procyon Instruments, London, UK). An additional approach is a wavefront aberrometer based on the Hartmann-Shack principle (WASCA; Asclepion-Meditec-Zeiss, Jena, Germany). These strategies were compared. DESIGN: Non-randomized comparative trial. PARTICIPANTS AND METHODS: The pupil diameter of 56 eyes of 28 probands (18 female, mean age 23 years) was measured under scotopic conditions by three independent examiners with each measurement device. The measurement devices were compared intraindividually by pairwise sign tests. Description was based on the intraindividual differences' medians and quantiles. RESULTS: Median pupil diameters were 6.67 mm for the scale pupillometer (interquartile range 6.07-6.94 mm), 6.60 mm for the dynamic pupillometer (6.0-7.02 mm), and 6.37 mm for the wavefront-based aberrometer (5.9-6.7 mm). Pairwise comparison revealed statistically significant ( P<0.05), although not clinically relevant median deviations. Although no clinically relevant median differences were observed (when based on intraobserver means), deviations for single pupil diameter assessments ranged up to 1 mm. CONCLUSION: No clinically relevant median deviations were observed in the underlying repeated measurement scenario. The scale pupillometer showed greater interobserver variation than the objective tests.

Adult↗

PubMed2003

Impact of head advance and oscillation rate on the flap parameter: a comparison of two microkeratomes.

PURPOSE: To compare flap quality and thickness in an experimental setting using the Amadeus and Carriazo/Barraquer microkeratomes. METHODS: One hundred and sixty-three fresh porcine cadaver eyes were used to cut corneal flaps. One hundred and thirty-five eyes were cut using the Amadeus microkeratome with various settings of head advance and oscillation rate, 28 eyes using the Carriazo/Barraquer microkeratome (Supratome). Flap diameter and hinge width were measured by planimetry and flap thickness by ultrasound pachymetry. Descriptive statistical analysis was based on medians and quartiles, graphical representation on box plots. The measurement devices were compared by two sample Wilcoxon tests, their deviation from the distributors' reference measurement values by sign tests. RESULTS: Variation of oscillation rate and head advance led to significant differences in flap thickness. Optimal cut quality was achieved with 1 mm/s head advance and 8,000 rpm in the Amadeus microkeratome. With this setting the smallest target deviations in flap thickness were obtained among the results with lowest range (median 170 micro m, interquartile range 18 micro m, target 160 micro m). The Amadeus microkeratome demonstrated a statistically significant lower deviation from the target thickness ( P<0.001) and also a lower range than the Supratome (median 127 micro m, interquartile range 30 micro m, target 140 micro m; P<0.001). CONCLUSIONS: Optimization of microkeratome settings leads to minimized deviation from target thickness and improved parameter. The Amadeus microkeratome achieved a statistically significant lower deviation in flap thickness than the Carriazo/Barraquer microkeratome. Individualization of the microkeratome settings may help to decrease flap complications and improve refractive outcome.

Animals↗

PubMed2003

The comparison of reliabilities in dental imaging methods.

OBJECTIVES: Common practice in the statistical comparison of imaging instruments with limited reproducibility consists in the separate estimation of the instrument's reliabilities. However, as soon as one of the imaging methods is subject to item-specific bias (which has to be expected in many dentomaxillofacial imaging procedures), this approach will end in severe errors in reliability computation and in corresponding erroneous clinical conclusions. This paper seeks to point out these effects and to illustrate a more appropriate model for the comparison of instrumental reliabilities. METHODS: A standard reliability model was adjusted for item-specific bias and illustrated by the comparison of twice repeated planimetric cephalometry versus twice repeated noninvasive orthodontic video imaging (based on the Digigraph 100 device) in 50 children; the anterior cranial base length was used for illustration. RESULTS: The proposed model revealed pronounced inferiority of the video-based imaging system concerning its reliability compared with the X-ray based standard. Analysis using separate estimation of the two reliabilities would result in the reverse conclusion and thus falsely establish video imaging, which is in fact less reliable, as a superior diagnostic method. CONCLUSION: The reliabilities of dentomaxillofacial imaging methods have to be adjusted for potential item-specific bias to avoid the erroneous conclusion of the superiority of a diagnostic innovation.

Adolescent↗

PubMed2003

Inhaled iloprost in patients with chronic thromboembolic pulmonary hypertension: effects before and after pulmonary thromboendarterectomy.

BACKGROUND: In primary pulmonary hypertension, aerosolized prostanoids selectively reduce pulmonary vascular resistance and improve right ventricular function. In this study, hemodynamic effects of inhaled iloprost, a stable prostacyclin analogue, were evaluated in patients with chronic thromboembolic pulmonary hypertension (CTEPH) before and early after pulmonary thromboendarterctomy (PTE). METHODS: Ten patients (mean age 49 years old [32 to 70 years old], New York Heart Association functional class III and IV) received a dose of 33 micro g aerosolized iloprost immediately before surgery (T1), after intensive care unit admission (T2), and 12-hours postoperatively (T3). Effects on pulmonary and systemic hemodynamics and gas exchange were recorded and compared with preinhalation baseline values. RESULTS: Preoperatively, inhaled iloprost did not significantly change mean pulmonary artery pressure (mPAP), cardiac index (CI), or pulmonary vascular resistance (PVR). Postoperatively, inhaled iloprost induced a significant reduction of mPAP and PVR and a significant increase of CI at T2 and T3. Preinhalation versus postinhalation PVR was as follows: at T1, 847 versus 729 dynes. s. cm(-5), p = 0.45; at T2, 502 versus 316 dynes. s. cm(-5), p = 0.008; and at T3, 299 versus 227 dynes. s. cm(-5), p = 0.004. CONCLUSIONS: In patients with CTEPH, inhalation of iloprost elicits no significant pulmonary vasodilation before surgery, and may have detrimental effects on systemic hemodynamics. Postoperatively, it significantly reduces mPAP and PVR, and enhances CI. Following PTE, inhalation of iloprost is useful to improve early postoperative hemodynamics.

Administration, Inhalation↗

PubMed2003

Comparison of biometric measurements using partial coherence interferometry and applanation ultrasound.

PURPOSE: To compare and contrast axial length (AL) measurements assessed by ultrasound biometry and optical biometry. SETTING: Department of Ophthalmology, Johannes Gutenberg-University, Mainz, Germany. METHODS: Optical biometry and ultrasound biometry were performed in 360 eyes to measure AL. RESULTS: In eyes with a clear-appearing crystalline lens, there was a statistically significant median difference in AL measurements between the 2 methods in eyes with a normal or long length. In eyes with cataract, there was a statistically significant median difference in AL measurements in eyes with a normal or short length. In these cases, optical biometry produced larger readings than ultrasound biometry. In eyes with a posterior chamber intraocular lens, there was no statistically significant difference between the 2 methods in eyes of all lengths. In all eyes, the 2 methods produced reliable measurements. CONCLUSIONS: These results show that optical biometry and ultrasound applanation biometry give statistically significant differences in AL measurement in patients with cataract and normal lenses. In these cases, optical biometry provided clinically relevant larger values than ultrasound applanation. Optical biometry provides an alternative to ultrasound biometry. However, ultrasound biometry may be indicated in certain complex cases.

Biometry↗

PubMed2003

Evaluation of the practicality of optical biometry and applanation ultrasound in 253 eyes.

PURPOSE: To evaluate the percentage of eyes that could not be measured using optical biometry and ultrasound applanation and the reasons. SETTING: Department of Ophthalmology, Johannes Gutenberg-University Hospital, Mainz, Germany. METHODS: Optical biometry (IOLMaster, Carl Zeiss Meditec AG) and A-scan ultrasound biometry were performed consecutively in 253 eyes scheduled for cataract surgery the next day. Lens opacities were evaluated with the Opacity Lensmeter (Interzeag), and a slitlamp examination and measurement of visual acuity were performed. The 2 techniques were compared in terms of the rate of and reasons for primary measurement failure. RESULTS: Measurement with the IOLMaster was not possible in 44 eyes (17%). Failed measurements were the result of a combination of low visual acuity and lens opacity in 45% of eyes, posterior subcapsular opacity in 25%, and macular disease in 7%. Measurement with ultrasound biometry was not possible in 10 eyes (4%); 7 eyes were filled with silicone oil and in 3 cases, the patient refused biometry. CONCLUSIONS: Optical biometry allowed comfortable, noncontact, high-precision measurement in the optical axis. Uncorrected visual acuity and lens opacity were predictors of successful measurements. Eyes with dense cataract or poor visual acuity are better evaluated using ultrasound applanation.

Adolescent↗

PubMed2003

Capsule measuring ring to predict capsular bag diameter and follow its course after foldable intraocular lens implantation.

PURPOSE: To evaluate the extent of capsular bag shrinkage after cataract surgery with intraocular lens (IOL) implantation and develop a regression formula to predict postoperative capsular bag size. SETTING: Eye Hospital, Johannes Gutenberg-University, Mainz, Germany. METHODS: The axial length (AL), anterior chamber depth, and corneal radius in 58 eyes were measured preoperatively. Cataract surgery was by phacoemulsification followed by implantation of a 3-piece, acrylic, posterior chamber IOL. The capsular bag diameter and anterior capsulorhexis were measured intraoperatively and 1 day and 1, 3, and 6 months postoperatively using a Koch capsule measuring ring (HumanOptics). RESULTS: The mean capsular bag size was 10.53 mm intraoperatively, 10.31 mm at 1 day, 9.62 mm at 1 month, 9.07 mm at 3 months, and 9.01 mm at 6 months. The mean capsular bag shrinkage over the entire postoperative period was 14.8% (P<.001). Of the parameters studied, only AL had a positive correlation with capsule shrinkage. The correlation was moderate but statistically significant (P =.001). CONCLUSIONS: A correlation was found between capsular bag shrinkage and AL. Using preoperative biometric data, a regression formula of moderate validity was determined to predict capsular bag shrinkage.

Acrylic Resins↗

PubMed2003

[VII: Diagnostic trials: Simple measures of validity and reliability].

The evaluation of a new diagnostic or imaging device has to focus both on its diagnostic validity and reliability. Cohen's kappa coefficient can be used to assess the agreement of the new device's findings with those of an established diagnostic reference, it therefore presents a surrogate measure of validity. Additional measures of validity are sensitivity and specificity, which assess the order of agreement with the reference for positive and negative reference findings, respectively. The latter, however, can only be applied for binary reference findings. If discordant findings are observed, the McNemar test can be used to detect a diagnostic shift between diagnostic novum and reference. The estimation of reliability can be based on the independent parallel rating of a patient subset by two clinical readers; again the kappa coefficient measures the agreement of the parallel ratings and therefore represents a surrogate measure of reliability. The McNemar test can be used to detect an observer bias.

Diagnostic Imaging↗

PubMed2003

[Refractive benefit and incremental costs of LASIK: results of a cost benefit study in two universities' LASIK departments].

BACKGROUND: No data is available to date on the cost effectiveness of laser in situ keratomileusis (LASIK) with regard to the German-speaking health care system. Hence we compared the clinical outcome and cost data of two German LASIK centres in respect of procedure cost effectiveness from the patient perspective. MATERIAL AND METHODS: A retrospective cohort study was implemented at the University Hospitals of Mainz and Mannheim. Data on refractive outcome were obtained from the LASIK centres' patient documentation, cost data on the surgery as well as on eyeglasses etc. before and after the surgery were obtained from patient interviews. The primary endpoint of this investigation was the individual incremental cost effectiveness ratio linking direct cost with the LASIK associated refractive gain. RESULTS: Clinical and economical data of 178 patients (Mainz: 45, Mannheim 133) was evaluated. After biplanar simultaneous LASIK 71% (Mainz) and 73% (Mannheim) reported, that they did not need eyeglasses etc. any longer after surgery; 31% (Mainz) versus 13% (Mannheim) had to undergo LASIK re-treatment. Median direct cost for the surgery was reported to be 3000 euro; (Mainz) versus 3910 euro; (Mannheim); the corresponding LASIK associated refractive gain was +5.6 D (median Mainz) versus +4.2 D (median Mannheim), resulting in median incremental cost effectiveness ratios of 667 euro; (Mainz) versus 831 euro; (Mannheim) per gained refractive unit. This investment has to be related to median annual cost of 250 euro; for eyeglasses etc. before surgery and 0 euro; afterwards. CONCLUSION: Depending on the performing surgical centre, German LASIK patients have to face a median investment of 667-831 euro; per gained refractive benefit unit. This incremental cost benefit ratio can be regarded as a surrogate parameter for comparison with alternative surgical or conservative treatment strategies in myopia.

Adolescent↗

PubMed2003

[VIII: Statistics in medical publications: check lists for authors].

The "Material and Methods" section of clinical research papers should reference major aspects concerning statistical planning and evaluation of the study design and the resulting clinical data. Particular focus is laid on the listing of methods for description and significance evaluation of the trial data, as well as on design-associated study determinants (randomisation and masking strategy, response rate evaluation, primary endpoints, power and sample size determination, multiple testing, software and methods for statistical analysis). Suggestions for the minimum content to be mentioned in a trial publication are listed in author check lists and are illustrated by means of the study synopsis of a randomised clinical trial on the rotation stability of two lens haptics.

Authorship↗

PubMed2003

[Cost effectiveness evaluation of cataract patient care in respect of monofocal intraocular lenses from the perspective of German statutory health insurance].

BACKGROUND: Data on the cost effectiveness of cataract surgery with respect to the German statutory health insurance system are hardly available. Hence the increase in visual acuity as primary efficacy endpoint, order of posterior capsule opacification as primary complication endpoint and direct cost for supplementation with monofocal intraocular lenses have been assessed via meta-analyses to evaluate the procedure's cost effectiveness from the perspective of the German statutory health insurance system. MATERIAL AND METHODS: Using the medical internet database MEDLINE two meta-analyses on publications between 1995 and 2002 were carried out, one estimating the gained increase in visual acuity, the second to estimate the frequency of posterior capsule opacification 5 years after implantation of a monofocal lens. To estimate the direct cost of German health insurance current reimbursement rates were used. The primary objective of this investigation was the individual incremental cost effectiveness ratio (ICER) linking the direct cost with the cataract surgery-associated increase in visual acuity. RESULTS: 51 studies were included in the meta analysis regarding the increase in visual acuity after cataract surgery. The median increase in visual acuity was about 5 visual units (interquartile range 3.6 - 8.0 units) reaching a median postoperative visual acuity of 0.8. The median incidence rate of posterior capsule opacification during the observed period of 5 years was estimated 24 % (10 - 34 %). Computation of the current reimbursement rates of German health insurance resulted in a median incremental cost of 223.25 euro; per gained visual unit. CONCLUSION: Providing of cataract patients with monofocal intraocular lenses means median incremental costs of about 223 euro; to be refunded by the health insurance and is associated with a median visual acuity outcome of 0.8. Therefore the cost effectiveness of cataract surgery can be regarded quite encouraging compared to the outcome of other ophthalmological outpatient surgery.

Cataract↗

PubMed2003

Volume flow in the common carotid artery does not decrease postprandially.

BACKGROUND AND PURPOSE: A commonplace explanation for postprandial fatigue is the assumption of the redistribution of perfusion from the cerebral to the mesenterial territory. However, this assumption has never been scientifically proven. METHODS: Because approximately 70% of the blood flow in the common carotid artery (CCA) is directed to the internal carotid artery, this vessel can be seen as a major brain-supplying artery. Flow volume in the CCA can be measured by color M-mode duplex sonography. The authors investigated the flow volume rate in 20 healthy volunteers before and after the intake of a high-energy meal. Heart rate, blood pressure, and expiratory CO2 were also measured at both times. RESULTS: There was a significant (P = .001) increase in right, left, and net CCA flow volume postprandially (right: from 362.0 [interquartile range 315.5-410.5] to 401.5 [322.1-486.4] mL/min; left: from 384.5 [345.5-439.0] to 414.5 [357.9-527.7] mL/min; net: from 756.0 [683.0-822.5] to 832.4 [713.7-967.26] mL/min). This increase was paralleled by a statistically significant increase in heart rate from 66 (58-70) to 76 (63-84) bpm, but without substantial correlation (r = 0.28) with the volume flow changes. There was no correlation with any other tested parameter. CONCLUSIONS: The authors conclude that the assumption of global brain hypoperfusion in the postprandial state cannot serve as an explanation for postprandial fatigue.

Adult↗

PubMed2002

Long-term results of cataract surgery combined with trabeculotomy.

BACKGROUND: There are different surgical approaches for cataract and concomitant primary open-angle glaucoma (POAG). In a retrospective study we examined the long-term results of cataract extraction combined with trabeculotomy. PATIENTS AND METHODS: Between 1990 and 1997, 194 eyes with cataract and POAG were operated on in a combined manner. Eighty-eight eyes received a trabeculotomy (TT), in 82 eyes a trabeculectomy was added to the trabeculotomy (TT+TE) and in 24 eyes, in which probing of Schlemm's canal was impossible, standard trabeculectomy (TE) was performed. Pre- and postoperative intraocular pressure (IOP), glaucoma medication, and the intra- and postoperative complications of all patients were analyzed. RESULTS: Hyphema was the most common complication in the TT group (20.5%). Fibrin reaction occurred in 27.8% of all cases. There was no statistically significant difference in postoperative IOP between the TT group and the TT+TE group. A statistically significant decrease in IOP compared to preoperatively lasted 60 months in the TT group. In eyes with a preoperative IOP < or = 20 mmHg, none of the three procedures reduced IOP significantly (<20% of the preoperative IOP). In the first 2 years after operation 50% of the patients had no need for antiglaucomatous medication. CONCLUSIONS: Cataract surgery combined with TT resulted in few complications. In low-tension glaucoma the combination with TT is not sufficient to decrease the IOP. In patients with higher preoperative IOP, however, cataract surgery combined with TT could be--on the basis of a postoperative observation time of 72 months--a suitable method for lowering the IOP sufficiently. Furthermore, the use of antiglaucomatous substances was reduced by this combined procedure.

Aged↗

PubMed2002

[Standard designs of epidemiological studies and their characteristics in ophthalmology].

This text gives an overview on standard epidemiological study designs and their main advantages and limitations concerning clinical and economical aspects, of performance. Ophthalmological examples are used to illustrate the design characteristics of cross-sectional, cohort and case control studies. These designs are compared by the fictitious planning of an epidemiological study to assess the prophylactical relevance of intraocular antibiotics against post-cataract endophthalmitis; general practical hints for the designing of epidemiological studies are given.

Antibiotic Prophylaxis↗