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Maximilian F Reiser

Publications and source records attributed to Maximilian F Reiser.

99 records · Page 6Linked to original sources
PubMedDate not supplied

Multiplanar reformat display technique in abdominal multidetector row CT imaging.

The purpose of this study was to evaluate the image quality and diagnostic value of multiplanar reformat (MPR) of abdominal CT performed with multidetector row spiral technique (MDCT). Forty-five patients were referred for an abdominal MDCT angiography. No significant differences in image quality and in the number of lesions detected were found between axial and MPR images (t-test, P>.90 and chi-square, P>.95). Additional diagnostic value to axial images could be obtained with MPR display.

Adult↗
PubMedDate not supplied

Likelihood of prostate cancer based on prostate-specific antigen density by MRI: retrospective analysis.

OBJECTIVE: As a screening test for prostate cancer (PCA), prostate-specific antigen (PSA) may induce unnecessary prostate biopsy in patients with PSA 4.1-10.0 ng/ml. PCA detection may be delayed in patients with PSA < or =4.0 ng/ml. MRI-based PSA density of the prostate (PSAD) and of the prostatic transitional zone (PSAT) could improve differentiation of PCA and benign prostatic hyperplasia. MATERIAL AND METHODS: Total prostate and transitional zone volumes were planimetrically determined in axial, T2-weighted fast spin echo MR images of the prostate. Serum PSA concentration was measured with an automated standardized microparticle enzyme immune assay. PSAD and PSAT were calculated in 17 patients with clinically significant PCA and 42 patients with benign prostatic hypertrophy (BPH) (66 +/- 6 versus 64 +/- 8 years, p = 0.2410, t test) who had PSA levels < or =10.0 ng/ml. RESULTS: For differentiation of BPH and PCA, PSA alone above the optimal cutoff level of 4.2 ng/ml showed an odds ratio for PCA of 6.7 (95% confidence interval [CI], 1.9-23.2). PSAD showed an odds ratio for PCA of 71.3 (95% CI, 11.8-430.9) above the optimal cutoff level of 0.07 ng/ml/cc. PSAT demonstrated an odds ratio for PCA of 320.0 (95% CI, 27.1-3781.4) above the optimal cutoff level of 0.15 ng/ml/cc. CONCLUSIONS: In patients with PSA < or =10.0 ng/ml, MRI-based PSAD and PSAT appear to improve differentiation of prostate cancer and BPH and are feasible to reduce the frequency of unnecessary prostate biopsy.

Aged↗
PubMedDate not supplied

Large core biopsy of the pancreas under CT fluoroscopy control: results and complications.

PURPOSE: The objective of this study was to evaluate the accuracy and complication rate of CT fluoroscopy-guided percutaneous core biopsies of the pancreas in patients with a suspected pancreatic neoplasm. MATERIALS AND METHODS: Sixty-three CT-guided biopsies were performed in 57 consecutive patients over a period of 20 months. Forty-nine of the 57 patients had a malignant lesion (85.9%). All procedures were done under CT fluoroscopic guidance. A high-speed biopsy gun with 14, 16, or 18 gauge cutting-type needles was used. Based on final pathologic diagnosis as the standard of reference, the diagnostic efficacy was determined. Complications during and afterward up to the patient's discharge from hospital (mean, 8.1 days; range, 1-48 days) were noted. RESULTS: Core biopsy of the pancreas resulted in a correct diagnosis in 51 of 63 biopsies, yielding a sensitivity for malignancy of 78.1%, a specificity of 100%, a positive predictive value of 100%, and an overall accuracy of 81.0%. One patient of 57 developed an acute pancreatitis related to the biopsy (1.6%). CONCLUSION: CT fluoroscopic-guided core biopsy is a safe and reliable tool for the pretherapeutic evaluation of pancreatic lesions.

Adult↗
PubMedDate not supplied

Detection of coronary artery stenoses with multislice helical CT angiography.

OBJECTIVES: The authors compared multislice CT angiography and selective angiography for the assessment of coronary artery disease. METHODS: In 28 patients, the presence and degree of coronary artery stenoses were determined in coronary segments prepared with beta-blocker for good image quality with multislice CT. RESULTS: In 187 coronary artery segments, sensitivity, specificity, and negative predictive value for the detection of stenoses >50% with multislice CT angiography were 81%, 90%, and 97%, respectively. The agreement for determining the degree of stenoses with multislice CT angiography and selective coronary angiography was only moderate (kappa = 0.58). CONCLUSIONS: Because of the limited spatial resolution, it is not possible with multislice CT angiography to determine the degree the coronary artery stenoses precisely. However, the high negative predictive value indicates that multislice CT may be a suitable tool to reliably rule out coronary artery disease.

Aged↗
PubMedDate not supplied

Assessment of myocardial infarctions using multidetector-row computed tomography.

OBJECTIVE: To evaluate the diagnostic power of contrast-enhanced multidetector-row computed tomography (MDCT) in assessing the presence, age, and size of myocardial infarctions. METHODS: One hundred six patients underwent standard MDCT coronary angiography without additional changes in the protocol. In all patients, a complete patient history and left heart catheterization with biplane contrast ventriculography were available. The MDCT images were reviewed for the presence and age of myocardial infarctions in a blinded fashion. Infarct areas were detected as regions of reduced uptake of contrast in the early arterial phase and/or regional wall thinning. Reviewing the computed tomography (CT) images, CT density values (Hounsfield units [HU]) were measured at the site of infarcted and noninfarcted myocardium, and a volumetric assessment of the infarct size was performed. RESULTS: In 27 of 106 patients, myocardial infarctions were present. Multidetector-row computed tomography detected 23 of 27 infarctions (sensitivity of 85%, specificity of 91%, and accuracy of 90%). Comparing the HU of infarcted versus noninfarcted myocardium, the mean HU of infarcted areas was 54 +/- 19 HU versus 117 +/- 28 HU for noninfarcted myocardium (P < 0.01). Multidetector-row computed tomography was able to differentiate between recent and chronic infarctions. The infarct volumes of recent infarctions (6.3 +/- 3.6 cm) showed a negative correlation to the ejection fraction (EF) according to contrast ventriculography (ie, the larger the infarct volumes as measured using MDCT, the worse was the EF [r = -0.72, P < 0.01]). CONCLUSIONS: Performing standard MDCT coronary angiography, areas of infarcted myocardium can be identified with moderate to high sensitivity, without additional scanning or contrast administration. Infarct localization can be assessed accurately as compared with cineventriculography. To some degree, infarct age and infarct volume can be estimated.

Aged↗
PubMedDate not supplied

Assessment of global left ventricular function: comparison of cardiac multidetector-row computed tomography with angiocardiography.

OBJECTIVE: Evaluation of left ventricular function using electrocardiogram (ECG)-gated multidetector row CT (MDCT) by using 3 different volumetric assessment methods in comparison to assessment of the left ventricular function by invasive ventriculography. METHODS: Thirty patients with suspected or known coronary artery disease underwent MDCT coronary angiography with retrospective ECG cardiac gating. Raw data were reconstructed at the end-diastolic and end-systolic periods of the heart cycle. To calculate the volumes of the left ventricle, 3 methods were applied: The 3-dimensional data set (3D), the geometric hemisphere cylinder (HC), and the geometric biplane ellipsoid (BE) methods. End-diastolic volumes (EDV), end-systolic volumes (ESV), the stroke volumes (SV), and ejection fractions (EF) were calculated. The left ventricular volumetric data from the 3 methods were compared with measurements from left ventriculography (LVG). RESULTS: The best results were obtained using the 3D method; EDV (r = 0.73), ESV (r = 0.88), and EF (r = 0.76) correlated well with the LVG data. The EDV volumes did not differ significantly between LVG and the 3D method (P = 0.24); however, ESV, SV, and EF differed significantly. The ESV were significantly overestimated (P < 0.01), leading to an underestimation of the SV (P < 0.01) and the EF (P < 0.01). The HC method resulted in the greatest overestimation of the volumes. The EDV and the ESV were 31.8 +/- 37.6% and 136.4 +/- 92.9% higher than the EDV and ESV volumes obtained by LVG. Bland-Altman analysis showed systematic overestimation of the ESV using the HC method. CONCLUSION: MDCT with retrospective cardiac ECG gating allows the calculation of left ventricular volumes to estimate systolic function. The 3D method had the highest correlation with LVG. However, the overestimation of the ESV is significant, which led to an underestimation of the SV and the EF.

Adult↗
PubMedDate not supplied

MRI-based PSA density and PSA density of the transitional zone compared with PSA alone: correlation with prostate cancer Gleason score.

OBJECTIVES: The tumor Gleason score is an important prognostic factor in prostate cancer (PCA). This retrospective study analyzes whether serum prostate-specific antigen (PSA), or magnetic resonance imaging (MRI)-based PSA density of the entire prostate (PSAD) or the prostatic transitional zone (PSAT) distinguishes between PCA of Gleason scores 6 or lower (G6-) and 7 or higher (G7+). MATERIALS AND METHODS: Total prostate and transitional zone volumes were planimetrically determined in axial, T2-weighted fast spin echo (FSE) MRI images of the prostate in 61 patients with previously untreated PCA. Automated standardized microparticle enzyme immuno-assay (EIAs) measured PSA. RESULTS: Thirty patients had G6- and 31 patients had G7+. PSA values ranged from 1.0 to 57.2 ng/mL. Assignment to G6- or G7+, respectively, was correct in 49 of 61 (80%) cases (odds ratio [OR], 17.1; 95% confidence interval [CI], 4.8-61.5) for PSA above the optimal cutoff level of 10.35 ng/mL, 48 cases (79%; OR, 13.7; 95% CI, 4.0-46.8) for PSAD above the optimal cutoff level of 0.23 ng/mL/cm, and 45 cases (74%; OR, 6.9; 95% CI, 2.2-21.3) for PSAT above the optimal cutoff level of 0.38 ng/mL/cm (no significant differences, McNemar test). CONCLUSIONS: In patients with biopsy-proven PCA, serum PSA level alone and MRI-based PSAD and PSAT help distinguish between G6- and G7+. PSAD and PSAT do not improve the level of confidence at which this discrimination is made.

Humans↗
PubMedDate not supplied

Radiofrequency ablation of colorectal liver metastases: mid-term results in 68 patients.

UNLABELLED: The aim of this retrospective study was to evaluate the efficacy and medium-term survival, after percutaneous radiofrequency ablation (RFA), in patients suffering from hepatic metastases of colorectal cancer. PATIENTS AND METHODS: Between 2000 and 2004, 68 patients (42 men, 26 women; mean age 63 years, range: 38-87 years), with non-resectable liver metastases from colorectal cancer, were treated by RFA subsequently or parallel to chemotherapy. The procedures were mainly performed under conscious sedation and local anesthesia using computed tomography fluoroscopy guidance. The number of lesions, the primary success rate, complications, follow-up time and disease-free survival, as well as the local recurrence rate, were evaluated. RESULTS: One-hundred and eighty-three metastases with a mean diameter of 22.8 mm (5-50 mm) in 68 patients (2.7 +/- 1.1 lesions / patient) were successfully treated using RFA. No major complications and only 4 minor complications were noted. Over an average follow-up period of 21.4 +/- 10.6 months (range, 8 to 38 months), Kaplan-Meier analysis demonstrated a probability of 82% of remaining locally disease-free and a probability of 68% of surviving the first 38 months after treatment. CONCLUSION: For patients with non-resectable hepatic metastases of colorectal cancer, RFA is a safe option in a multimodal treatment concept and may lead to an improvement in survival.

Adult↗