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Featured researches published by R. Vosshenrich.


European Radiology | 2002

Classification of hypervascularized lesions in CE MR imaging of the breast

Friedemann Baum; Uwe Fischer; R. Vosshenrich; E. Grabbe

Abstract. The purpose of this paper is to define and evaluate a classification category for contrast-enhanced (CE) MR imaging of the breast based on the BI-RADS mammographic categories of the American College of Radiology. Using five evaluation criteria for MR findings (initial signal increase, postinitial signal behavior, shape, border, and contrast material distribution within enhancing tumors) 522 patients (1031 breasts) were analyzed. Scores were given from 0 to 8 points and classified into five categories (group I: 0 points, negative; group II: 1–2 points, benign; group III: 3 points, probably benign; group IV: 4–5 points, suspicious abnormality; group V: 6–8 points, highly suspicious for malignancy) to 265 focal hypervascularized breast lesions in 244 breasts (patient group A). These findings were correlated with histology or follow-up. Additionally, this classification was correlated to the contrast medium uptake within the parenchyma of the remaining 787 breasts without any focal lesion (patient group B). Two hundred sixty-five hypervascularized lesions in 238 patients (244 breasts, patient group A) were classified into group I: 0%; group II: 27.3%; group III: 22.3%; group IV: 18.6%; and group V: 31.8%. Histology revealed 115 benign and 134 malignant tumors in these groups. Sixteen benign lesions were controlled by follow-up. Sensitivity for the detection of malignancy using the presented multifactorial MRM classification was 92%, and specificity was 92%. Excluding cases of ductal carcinoma in situ specificity increased to 95%. Seven hundred eighty-seven breasts without any focal hypervascularized lesion (patient group B) were classified into groups I or II. Follow-up (n=771) or histology (n=14) confirmed the diagnosis in 785 of these breasts. Histopathology revealed, however, malignant tumors in the remaining two cases. The classification of lesions based on a multifactorial analysis is very helpful in the interpretation of CE MRI of the breast. The evaluation of all diagnostic imaging modalities, however, is essential in determining the correct diagnosis and/or in deciding on the appropriate therapeutic procedure.


European Radiology | 2002

Comparative study in patients with microcalcifications: full-field digital mammography vs screen-film mammography

Uwe Fischer; Friedemann Baum; Silvia Obenauer; Susanne Luftner-Nagel; D. von Heyden; R. Vosshenrich; E. Grabbe

Abstract. The goal of this prospective study was to compare a full-field digital mammography system (FFDM) to a conventional screen-film mammography system (SFM) for the detection and characterization of microcalcifications. Fifty-five patients with 57 isolated microcalcification clusters were examined using a FFDM system (Senographe 2000D, GE Medical Systems, Milwaukee, Wis.) and a SFM system (Senographe DMR, GE Medical Systems, Milwaukee, Wis.). A conventional screen-film mammogram and a digital contact mammogram were obtained of each cluster. The image quality and the number of calcification particles were evaluated, and a characterization (BI-RADS 1–5) of microcalcifications was given by four experienced readers. Histopathology revealed 16 benign lesions (sclerosing adenosis, dysplasia, hamartoma, radial scar) in 15 patients and 21 malignant tumors (in situ carcinoma, invasive carcinoma) in 20 patients. Twenty patients had benign changes verified by long-term follow-up. Image quality of FFDM was assessed as superior to SFM in more than 50% of the cases. The FFDM showed more calcifications in 41% of all cases. Sensitivity and specificity for FFDM vs SFM were 95.2 vs 91.9% and 41.4 vs 39.3%, respectively. Moreover, FFDM demonstrated a higher diagnostic accuracy (deviation: 0.86 BI-RADS steps) compared with FSM (deviation 0.93 BI-RADS steps). The FFDM system with a 100-µm pixel size provides better image quality than SFM in patients with mammographic microcalcifications. The FFDM has a higher sensitivity and a higher reliability in characterizing microcalcifications.


The Journal of Urology | 1997

Sexual Dysfunction in Peyronie's Disease: An Analysis of 222 Patients Without Previous Local Plaque Therapy

W. Weidner; Immo Schroeder-Printzen; Wolf-H. Weiske; R. Vosshenrich

PURPOSE We obtained an objective evaluation of erectile function in patients with Peyronies disease. MATERIALS AND METHODS Sexual dysfunction was analyzed in 222 patients with Peyronies disease without previous local plaque therapy using a standardized protocol. RESULTS Of the 222 patients 70 (31.5%) complained of not being able to perform intercourse. In 4 men (1.8%) standardized diagnostic procedure demonstrated only a severe angulation making coitus impossible, and in 3 men (1.4%) intercourse became unsatisfactory due to pain. Seven men (3.1%) reported distal penile flaccidity, including 4 in whom dynamic pharmacocavernosometry and pharmacocavernosography revealed veno-occlusive dysfunction. Of 56 men who complained of a complete loss of erection 51 did not respond to intracavernous pharmacological injection with prostaglandin E1, and 27 (48.2%) had abnormal arterial blood flow as shown by duplex sonography of the cavernous arteries, 47 (83.9%) had evidence of veno-occlusive dysfunction based on cavernosometric criteria and 33 (58.9%) also had cavernosographic evidence of the condition. Plaque associated venous drainage was evident in 15 of the 56 impotent patients (26.8%), equivalent to 45.5% of all cases with abnormal cavernosographic findings. CONCLUSIONS Sexual dysfunction was evaluable in 31.5% of patients, and the main cause of impotence and loss of erection was veno-occlusive dysfunction.


European Radiology | 2002

Contrast-enhanced MR angiography of abdominal vessels: is there still a role for angiography?

R. Vosshenrich; Uwe Fischer

The purpose of this review article is to describe recent advantages in contrast-enhanced (CE) three-dimensional (3D) magnetic resonance angiography (MRA) in comparison with other vascular imaging techniques, and to discuss their current clinical applications for the imaging of abdominal vessels. Principles and technical considerations are presented and clinical applications are reviewed for different vascular diseases. In ruptured aortic aneurysms and acute dissections CT is the method of first choice. Contrast-enhanced 3D MRA can be well used for therapeutic planning and follow-up in patients with stable disease. A comprehensive MR examination including CE 3D MRA, MR urography and MR nephrogram has the potential to replace the conventional studies for the evaluation of renal vascular disease. It is an accurate method for imaging the origins of coeliac and superior mesenteric arteries, although the image resolution is too low for reliable assessment of the inferior mesenteric artery. Contrast-enhanced 3D MRA has emerged as the method of choice for studying the portal venous system in liver transplant recipients, in patients with portal hypertension and in cases with abdominal tumours for preoperative evaluation. Additional non-invasive flow measurements are useful in monitoring portal hypertension. The abdominal veins can be well imaged using unenhanced MR techniques. Imaging may be facilitated with intravascular contrast media. Contrast-enhanced 3D MRA can replace intra-arterial DSA for diagnosis, therapy planning and follow-up in patients with abdominal vascular disease. Catheter-based arteriography will still be used for interventional procedures such as percutaneous transluminal angioplasty, stent placement and embolisation.


Clinical Imaging | 2003

MRI in the evaluation of müllerian duct anomalies.

Katharina Marten; R. Vosshenrich; M. Funke; Silvia Obenauer; Friedemann Baum; E. Grabbe

OBJECTIVE Müllerian duct anomalies (MDAs) result from nondevelopment or nonfusion of the müllerian ducts and occur in 1-5% of women. Accurate diagnosis of the various subtypes is of great importance as MDAs are frequently associated with a broad variety of clinical symptoms. Recently, evidence arose that MRI might play a major role in diagnosis of MDAs. We present four cases of diverse subtypes of MDAs and the corresponding MRI findings. MATERIALS AND METHODS Patients (n = 4) with clinical suspicion of MDAs were examined with MRI. Coronal and transaxial T1- and T2-weighted images were acquired. Diagnosis was made and patients were grouped according to the American Fertility Societys classification. Patients underwent laparoscopy or laparotomy in order to confirm the diagnosis. RESULTS MRI revealed MDAs in all patients. In detail, one patient was diagnosed with hypoplastic uterus, one with unicornuate uterus with a noncommunicating rudimentary horn, one with bicornuate uterus bicollis with a double vagina and one with septate uterus. MRI diagnosis was correct in all cases, as confirmed by subsequent surgical intervention. CONCLUSION MRI is a valuable tool in diagnosis of MDA subtypes. Its use will help to spare patients mutilating surgery and to prevent pregnancy-associated complications.


European Urology | 2003

Diagnostic Value of Magnetic Resonance Imaging in Peyronie’s Disease—A Comparison Both with Palpation and Ultrasound in the Evaluation of Plaque Formation ☆

Ekkehard W. Hauck; Nils Hackstein; R. Vosshenrich; Thorsten Diemer; Hans U. Schmelz; T. Bschleipfer; I. Schroeder-Printzen; W. Weidner

OBJECTIVE To compare the value of magnetic resonance imaging (MRI) with palpation and ultrasound in the evaluation of plaque formation in Peyronies disease. METHODS 57 patients underwent a standardized diagnostic procedure to evaluate plaque formation consisting of palpation and ultrasonography (7.5 MHz). MRI was performed during flaccidity and during erection induced by Prostaglandin E(1) including intravenous application of Gadolinium-diethylenetriaminepentaacetic acid (Gd-DPTA). RESULTS With all methods, 93 plaques have been detected in 57 patients. 85 plaques (91.4%) have been evaluated by palpation alone. Using ultrasound, 52 of these 93 plaques (55.9%) were detectable. This is equivalent to 61.1% of the palpable plaques. MRI confirmed 58 of the palpated plaques (68.2%) and exposed 8 primarily not palpable plaques at the penile basis. MRI revealed more palpable plaques than ultrasound, but this finding was not significant (p = 0.083). By means of sonography, calcification was evident in 14 plaques. MRI failed in revealing any calcification. After application of Gd-DPTA, 5 of 57 patients (9%) demonstrated contrast enhancement indicating local inflammation. None of these patients reported on penile pain. CONCLUSIONS Penile palpation in combination with ultrasound represents the method of choice to diagnose plaque formation in Peyronies disease. MRI provides better information on plaque formation at the penile basis. Calcification can only be proven by ultrasound, not by MRI. There may be additional information by MRI about local inflammation. A prospective study comparing the histological and MRI findings should be performed to answer the question, if pain is really associated with inflammation.


The Journal of Urology | 1995

Value of Magnetic Resonance Imaging in Patients With Penile Induration (Peyronie's Disease)

R. Vosshenrich; Immo Schroeder-Printzen; W. Weidner; Uwe Fischer; M. Funke; Rolf-H. Ringert

Magnetic resonance imaging (MRI) is a noninvasive procedure that enables exact imaging of penile anatomy. A total of 34 patients with clinical Peyronies disease underwent palpation, ultrasound and MRI after intracavernous injection of 10 micrograms. prostaglandin E1. MRI images were obtained before and after intravenous application of gadolinium-diethylenetriaminepentaacetic acid. In 34 patients 45 plaques were palpable. Ultrasound revealed evidence of lesions in 66.6% of the cases. On MRI 36 of 45 palpable plaques (80%) were detected. Not palpable or sonographically revealed indurations could be shown in 4 cases. After intravenous application of gadolinium-diethylenetriaminepentaacetic acid 4 plaques demonstrated contrast enhancement, thus indicating local inflammatory activity. The combination of clinical examination and sonography remains the method of choice for diagnosis and observation of patients with Peyronies disease. MRI enables exact imaging of penile structures but it does not provide a significant advantage over standard investigative procedures.


Urologia Internationalis | 1994

Malignant Priapism in a Patient with Metastatic Prostate Adenocarcinoma

J. Schroeder-Printzen; R. Vosshenrich; W. Weidner; R.H. Ringert

Metastases to the penis due to a primary carcinoma of the prostate are rare. In approximately half of the patients, malignant priapism is the main symptom. This study reports on a case of malignant priapism, caused by a direct and metastatic infiltration of the corpora cavernosa by a prostatic adenocarcinoma. Sonography gave hints, the magnetic resonance imaging verified the infiltration and aspiration cytology verified the carcinoma. Hemodynamics, evaluated by Doppler sonography, and intracavernosal blood gas analysis demonstrated a mixed high-low priapism without need of therapy.


Journal of Computer Assisted Tomography | 1995

MR-guided localization of suspected breast lesions detected exclusively by postcontrast MRI.

Uwe Fischer; R. Vosshenrich; Harald Bruhn; David P. Keating; Björn W. Raab; Jörg W. Oestmann

Objective We describe and evaluate a preoperative MRI localization procedure for suspected breast lesions. Materials and Methods Fourteen consecutive patients underwent MR localization of suspected breast lesions discovered with contrast-enhanced MRI but not detected by conventional mammography or ultrasound. In each case diagnostic MRI was repeated after the application of special skin markers. A nonmagnetic wire was subsequently inserted into the breast and a second MRI performed to document the position of the wire tip relative to the lesion. Results The procedure was successful in all 14 patients, enabling excision of the lesion and allowing histological diagnoses. Conclusion We found the described procedure to be quite useful.


Journal of Computer Assisted Tomography | 1996

Detection of renal ischemic lesions using Gd-DTPA enhanced turbo FLASH MRI: Experimental and clinical results

R. Vosshenrich; M. Kallerhoff; Hermann Josef Gröne; Uwe Fischer; M. Funke; L. Kopka; Gesine Siebert; Rolf H. Ringert; E. Grabbe

PURPOSE Our goal was to investigate the role of Gd-DTPA-enhanced dynamic MRI in the evaluation of renal ischemic lesions. METHOD With a turbo FLASH sequence before and after injection of Gd-DTPA, nine foxhound dogs after 60-120 min of renal ischemia underwent MR examination. In addition, five patients with a tumor in a solitary kidney were examined before and after nephron-sparing renal surgery to evaluate renal perfusion and function. The experimental and clinical findings were correlated with conventional measurements of kidney function and with histological findings. RESULTS Complete renal ischemia leads to a poor corticomedullary differentiation in Gd-DTPA-enhanced turbo FLASH MRI. The signal-intensity-versus-time plots of kidneys with significant postischemic changes show a less steep increase of signal intensity in the cortex and a steeper increase of signal intensity in the medulla than those of normal kidneys. CONCLUSION Dynamic MRI demonstrate renal morphology and reflect the functional status of renal vasculature.

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E. Grabbe

University of Göttingen

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Uwe Fischer

University of Göttingen

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M. Funke

University of Göttingen

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L. Kopka

University of Göttingen

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W. Weidner

University of Göttingen

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Lars Kopka

Humboldt University of Berlin

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Björn-W. Raab

University of Göttingen

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