Gertraud Heinz-Peer

A combined high temporal and high spatial resolution 3 Tesla MR imaging protocol for the assessment of breast lesions: initial results.

Purpose:To develop a 3.0 Tesla breast imaging protocol that combines high temporal and spatial resolution three-dimensional MR sequences for quantitative time course and morphologic analysis of breast lesions. Materials and Methods:Thirty-four patients were included in the study (age range, 31–82; mean age, 54.3). The study protocol was approved by the Institutional Review Board and written informed consent was obtained from all patients. The magnetic resonance imaging protocol included: a coronal T1-weighted volume-interpolated-breathhold-examination sequence, focused on high temporal resolution for optimal assessment of the contrast-enhancement behavior of lesions (SI 1.7 mm isotropic; TA 3.45 minutes for 17 measurements); a coronal T1-weighted turbo fast-low-angle-shot-three-dimensional sequence, with water-excitation and fat suppression, focused on high spatial resolution for morphologic analysis (SI 1 mm isotropic; TA 2 minutes); and a repeated coronal volume-interpolated-breathhold-examination sequence for detection of washout. Lesion size and morphology were assessed. Region-of-interests for suspicious areas were manually drawn and evaluated for contrast-enhancement behavior by plotting intensity courses against time. Sensitivity and specificity with a 95% confidence interval and the negative predictive value and positive predictive value were calculated. Diagnostic accuracy was assessed. The histopathological diagnoses were used as a standard of reference. Results:Fifty-five lesions were detected in 34 patients. All malignant breast lesions were identified correctly. There were 5 false-positive lesions. The sensitivity of contrast-enhanced magnetic resonance imaging of the breast at 3 T was 100%, with a 95% confidence interval (CI) of 90.6% to 100%. The specificity was 72.2%, with a 95% CI of 49.1% to 87.5%. The positive predictive value was 0.88 and the negative predictive value was 1. Diagnostic accuracy was 91% with a 95% CI of 80.4% to 96.1%. Conclusion:Our prospective study demonstrates that the presented 3 Tesla MR imaging protocol, comprising both high temporal and high spatial resolution, enables accurate detection and assessment of breast lesions.

Renal tumour size measured radiologically before surgery is an unreliable variable for predicting histopathological features: benign tumours are not necessarily small

To compare histopathological findings as a function of radiological tumour size, as published data suggest that small renal tumours are often benign and large tumours are renal cell cancer (RCC).

How accurate is MR imaging in characterisation of adrenal masses: update of a long-term study

OBJECTIVE The purpose of this study was to update a long-term study that evaluates the accuracy of MR imaging in the characterisation of adrenal tumours. In all patients, MR imaging findings were correlated with histopathologic results. PATIENTS In 204/560 patients who underwent MR imaging for characterisation of an adrenal mass, histopathologic results were available. The final study group consisted of 229 adrenal masses in 204 patients. MR imaging was performed using T2-weighted fast spin-echo imaging and unenhanced and gadolinium-enhanced T1-weighted spin-echo imaging in all patients. In addition, chemical shift imaging was performed in 182 patients and dynamic gadolinium-enhanced studies in 198 patients. Chemical shift images and dynamic studies were qualitatively assessed. All images were reviewed by an experienced investigator (Gertraud Heinz-Peer) who was blinded to the clinical history and the results of prior imaging studies. RESULTS The sensitivity of MR imaging for the differentiation of benign and malignant adrenal masses was 89%, the specificity 99%, and the accuracy was 93.9%. This results in a positive predictive value (PPV) of 90.9% and a negative predictive value (NPV) of 94.2%. These results are comparable to the data published previously by our study group with a lower number of cases. CONCLUSION Large study numbers show that MR imaging is a reliable method in characterisation of benign and malignant adrenal masses. Since laparoscopic adrenalectomy has become the new gold standard in the surgical treatment of benign adrenal lesions, the high accuracy of MR imaging in characterisation of those lesions offers even patients with large adrenal masses (>5 cm) the advantages of the minimally invasive technique.

Detection of focal hepatic lesions: comparison of unenhanced and SHU 555 A-enhanced MR imaging versus biphasic helical CTAP.

The purpose of this study was to compare the diagnostic sensitivity of unenhanced magnetic resonance (MR) imaging, and MR imaging with a new superparamagnetic iron oxide (SPIO)‐enhanced contrast agent (SHU 555 A) with biphasic helical computed tomography during arterial portography (CTAP) in patients with focal liver lesions. Eighteen patients with a total of 91 (78 malignant, 13 benign) proven liver lesions underwent unenhanced short tau inversion recovery (STIR), T2‐weighted (T2‐w) TSE, and SHU 555 A‐enhanced T2‐w turbo spin‐echo (TSE) MR imaging and biphasic helical CTAP. The standard of reference was histopathologic analysis of resected specimens in 59 lesions, intraoperative ultrasound with biopsy in 20 lesions, and CT‐guided biopsy and follow‐up in 12 lesions. Diagnostic performance of the imaging modalities was compared quantitatively and qualitatively by assessing lesion involvement in liver segments. There were 68 lesions detected on unenhanced T2‐w TSE, which resulted in a sensitivity of 75%. With the STIR sequence, 76 lesions were detected, for a sensitivity of 84%, and with SHU 555 A‐enhanced MRI, 84 lesions were detected, for a sensitivity of 92%. CTAP detected 88 lesions, for a sensitivity of 97%. The accuracy for unenhanced T2‐w TSE was 98%, for STIR 99%, for enhanced‐MRI 100%, and for CTAP 95%. The specificity was 100% for SHU 555 A‐enhanced MRI and 95% for CTAP. SHU 555 A‐enhanced MRI was superior to nonenhanced MRI (P < 0.05) and equivalent to CTAP in terms of sensitivity. Due to the absence of false‐positive results on SHU 555 A‐enhanced MRI, the specificity and accuracy of enhanced MRI were higher than those of CTAP, but the difference was not statistically significant (P = 0.134). J. Magn. Reson. Imaging 2000;11:665–672.

Enhancement of liver parenchyma after injection of hepatocyte-specific MRI contrast media: a comparison of gadoxetic acid and gadobenate dimeglumine

To compare enhancement of liver parenchyma in MR imaging after injection of hepatocyte‐specific contrast media.

MAGNETIC RESONANCE IMAGING IN HEMOPHILIC CHILDREN: VALUE OF GRADIENT ECHO AND CONTRAST-ENHANCED IMAGING

The purpose of this study was to determine the value of Gradient Echo imaging for the evaluation of cartilage (3D fatsat) and blood products (2D Hemoflash), and the use of contrast enhanced SE imaging for the evaluation of synovial changes, in comparison to the clinical evaluation of children with hemophilia A. We investigated 21 joints in 16 patients with evidence of hemophilia A (mean age 11.3+/-2.1 years). In all patients, clinical examination, plain film radiographs, and MR evaluation were performed magnetic resonance imaging (MRI) was performed by using sagittal T1 SE and T2 SE images, as well as 3D fatsat GE and 2D GE images. Axial and sagittal T1 weighted SE images were obtained before and after contrast application. Findings from the clinical examination and MR imaging, regarding the evaluation of blood, synovia, and cartilage were compared. Clinical examination revealed evidence of a bleeding episode in 12 joints (57.1%), whereas MRI revealed evidence of blood or blood products in 15 joints (71.4%). Clinical investigations, including bleeding scores, pain scores, and physical examination scores did not correlate with MR findings. Due to the MR findings in 6 of 16 patients, therapeutic management was changed from on demand to prophylactic therapy. MR imaging with gradient echo and contrast-enhanced sequences is more sensitive than clinical examination for the detection of blood products in children with hemophilia. Its ability to demonstrate potentially early stages of cartilage or synovial alterations might assist in therapy planning. Clinical scores might underestimate effects of hemophilia.

Paclitaxel and carboplatin in patients with metastatic transitional cell cancer of the urinary tract

OBJECTIVES The combination of methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) is currently considered the most effective chemotherapy for metastatic transitional cell cancer (TCC) of the urinary tract, but because of its considerable toxicity, alternative regimens appear very interesting. We evaluated the efficacy and toxicity of a combination of paclitaxel and carboplatin as first-line therapy for metastatic TCC. METHODS Thirty-two patients (8 women, 24 men; mean age 67.03 years, range 50 to 79) with metastatic TCC of the bladder or upper urinary tract were included in the study. Paclitaxel (175 mg/m2) was given as a 3-hour intravenous infusion, carboplatin was dosed to an area under the plasma concentration curve of 5 mg/m/min calculated according to the Calvert formula [(creatinine clearance + 25) x 5] as a 30-minute intravenous infusion immediately after paclitaxel. Response evaluation was performed after every 2 cycles and additional therapy depended on response. The maximum number of cycles was 6. RESULTS With a mean follow-up of 13.1 months (range 2 to 28), 23 of 32 patients responded to treatment (response rate 71.9%), with 31.3% complete remission (CR) (10 of 32) and 40.6% partial remission (PR) (13 of 32). Four patients (12.5%) had stable disease, and 5 patients (15.6%) showed progression. These results compare well with the outcome after MVAC. Toxicity was mainly characterized by neurotoxicity grade 3 and 4 in 9.4%, grade 3 and 4 leukopenia in 37.5%, and grade 3 thrombocytopenia in 3.1% of the patients. No nephrotoxicity was observed, but all patients developed alopecia. Time to progression after CR was a mean of 7.0 months (range 4 to 13) and after PR a mean of 5.9 months (range 2 to 9). CONCLUSIONS Paclitaxel/carboplatin is an effective therapy for metastatic TCC, with low toxicity.

Implantable Microballoons: An Attractive Alternative in the Management of Intrinsic Sphincter Deficiency

Purpose: All current bulking agents employed for treating stress urinary incontinence (SUI) have significant limitations due to various side effects, technical difficulties and inadequate long-term results. Implantable microballoons were therefore tested as a new therapeutic modality for female urinary incontinence. Material and Methods: The microballoons are implanted with a new system which consists of the self-detachable cross-linked silicone balloon, biocompatible filler material and a delivery system. Nineteen female patients (mean age 63.3 years) with SUI grade 1 or 2 were studied prospectively. Using the Blaivas-Olsson classification, 6 patients had stress incontinence type I, 4 had type II and 9 had type III. Three to seven balloons (mean 4.2) were implanted per patient. Patients were followed up with pad tests (g) and determination of leak point pressure (LPP; cm H2O) and maximal urethral closing pressure (Pura max; cm H2O) at 1, 3, 6, 12 and 18 months. Results: The biocompatibility of the microballoons was excellent. No significant adverse events were associated with the procedure. With a mean follow-up of 14.4 months (range 10–18) 42.1% (8/19) of the women are dry. In the latter the pad test improved from a preoperative mean of 22.6 g (2–75) to 0 and the LPP increased from a preoperative mean of 38.5 cm H2O (25–60) to 80.5 cm H2O (68–106). 36.8% (7/19) of the patients showed significant improvement of their incontinence. In this group the pad test improved from a preoperative mean of 39.1 g (8–112) to 9.7 g (2–29) and LPP from a mean of 37.1 cm H2O (25–50) to 42.0 cm H2O (30–58). In 4 patients (21.05%) the technique failed. Seven of the 8 cured patients had type III incontinence; the eighth patient had type I incontinence. It failed in all patients with type II incontinence. Conclusion: The implantation of microballoons is a safe, well-tolerated and clinically effective modality for the treatment of type III SUI, i.e. intrinsic sphincter deficiency.

Perioperative, Oncologic, and Functional Outcomes of Laparoscopic Renal Cryoablation and Open Partial Nephrectomy: A Matched Pair Analysis

PURPOSE To directly compare perioperative, oncologic, and functional outcomes of laparoscopic renal cryoablation and open partial nephrectomy using a matched pair analysis. PATIENTS AND METHODS A total of 41 patients who underwent laparoscopic cryoablation for an incidental, solid clinical T(1a)N(0)M(0) renal tumor were matched with 82 patients who received partial nephrectomy in cold ischemia, using optimal matching based on propensity scores, which were created on the basis of preoperative aspects and dimensions used for an anatomic classification of renal tumors (PADUA) score, preoperative glomerular filtration rate, age-adjusted Charlson comorbidity index, and sex. Median follow-up was 33.6 months. RESULTS No differences in the overall incidence of complications (cryoablation, 20%; partial nephrectomy, 17%; P=0.739) and grade of complications (P=0.424) were observed. After cryoablation, local recurrence developed in four patients with renal-cell carcinoma (n=35) after a median duration of 14 months (range 6-18  mos), but none after partial nephrectomy. The 3-year recurrence-free survival probabilities after laparoscopic renal cryoablation vs open partial nephrectomy were 83% vs 100%, respectively (P=0.015). The average decrease of estimated glomerular filtration rate during follow-up was 7.8±3.1  mL/min/1.73  m(2) after laparoscopic cryoablation and 9.8±2.3  mL/min/1.73  m(2) after open partial nephrectomy, which was not statistically significant (P=0.602). CONCLUSIONS Perioperative complications and renal functional outcomes of laparoscopic cryoablation and open partial nephrectomy are similar; however, laparoscopic cryoablation confers a substantially higher local recurrence risk of about 17% after 3 years. Therefore, laparoscopic renal cryoablation should be reserved for high-risk patients with decreased life expectancy. Careful patient counseling is advocated. Study limitations include the small sample size, the lack of randomization, and the short follow-up.

Utility and limitations of 3-Tesla diffusion-weighted magnetic resonance imaging for differentiation of renal tumors

OBJECTIVE To investigate utility and limitations of 3-Tesla diffusion-weighted (DW) magnetic resonance imaging (MRI) for differentiation of benign versus malignant renal lesions and renal cell carcinoma (RCC) subtypes. MATERIALS AND METHODS Sixty patients with 71 renal lesions underwent 3 Tesla DW-MRI of the kidney before diagnostic tissue confirmation. The images were retrospectively evaluated blinded to histology. Single-shot echo-planar imaging was used as the DW imaging technique. Apparent diffusion coefficient (ADC) values were measured and compared with histopathological characteristics. RESULTS There were 54 malignant and 17 benign lesions, 46 lesions being small renal masses ≤ 4 cm. Papillary RCC lesions had lower ADC values (p=0.029) than other RCC subtypes (clear cell or chromophobe). Diagnostic accuracy of DW-MRI for differentiation of papillary from non-papillary RCC was 70.3% resulting in a sensitivity and specificity of 64.3% (95% CI, 35.1-87.2) and 77.1 (95% CI, 59.9-89.6%). Accuracy increased to 83.7% in small renal masses (≤ 4 cm diameter) and sensitivity and specificity were 75.0% and 88.5%, respectively. The ADC values did not differ significantly between benign and malignant renal lesions (p=0.45). CONCLUSIONS DW-MRI seems to distinguish between papillary and other subtypes of RCCs especially in small renal masses but could not differentiate between benign and malignant renal lesions. Therefore, the use of DW-MRI for preoperative differentiation of renal lesions is limited.