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1.
Ultraschall Med ; 43(6): 570-582, 2022 Dec.
Article in English, German | MEDLINE | ID: mdl-34921376

ABSTRACT

For many years, breast ultrasound has been used in addition to mammography as an important method for clarifying breast findings. However, differences in the interpretation of findings continue to be problematic 1 2. These differences decrease the diagnostic accuracy of ultrasound after detection of a finding and complicate interdisciplinary communication and the comparison of scientific studies 3. In 1999, the American College of Radiology (ACR) created a working group (International Expert Working Group) that developed a classification system for ultrasound examinations based on the established BI-RADS classification of mammographic findings under consideration of literature data 4. Due to differences in content, the German Society for Ultrasound in Medicine (DEGUM) published its own BI-RADS-analogue criteria catalog in 2006 3. In addition to the persistence of differences in content, there is also an issue with formal licensing with the current 5th edition of the ACR BI-RADS catalog, even though the content is recognized by the DEGUM as another system for describing and documenting findings. The goal of the Best Practice Guideline of the Breast Ultrasound Working Group of the DEGUM is to provide colleagues specialized in senology with a current catalog of ultrasound criteria and assessment categories as well as best practice recommendations for the various ultrasound modalities.


Subject(s)
Breast Neoplasms , Medicine , Female , Humans , Ultrasonography, Mammary/methods , Mammography/methods , Breast Neoplasms/diagnostic imaging
2.
Radiology ; 262(2): 435-49, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22282182

ABSTRACT

PURPOSE: To determine whether adding shear-wave (SW) elastographic features could improve accuracy of ultrasonographic (US) assessment of breast masses. MATERIALS AND METHODS: From September 2008 to September 2010, 958 women consented to repeat standard breast US supplemented by quantitative SW elastographic examination in this prospective multicenter institutional review board-approved, HIPAA-compliant protocol. B-mode Breast Imaging Reporting and Data System (BI-RADS) features and assessments were recorded. SW elastographic evaluation (mean, maximum, and minimum elasticity of stiffest portion of mass and surrounding tissue; lesion-to-fat elasticity ratio; ratio of SW elastographic-to-B-mode lesion diameter or area; SW elastographic lesion shape and homogeneity) was performed. Qualitative color SW elastographic stiffness was assessed independently. Nine hundred thirty-nine masses were analyzable; 102 BI-RADS category 2 masses were assumed to be benign; reference standard was available for 837 category 3 or higher lesions. Considering BI-RADS category 4a or higher as test positive for malignancy, effect of SW elastographic features on area under the receiver operating characteristic curve (AUC), sensitivity, and specificity after reclassifying category 3 and 4a masses was determined. RESULTS: Median participant age was 50 years; 289 of 939 (30.8%) masses were malignant (median mass size, 12 mm). B-mode BI-RADS AUC was 0.950; eight of 303 (2.6%) BI-RADS category 3 masses, 18 of 193 (9.3%) category 4a lesions, 41 of 97 (42%) category 4b lesions, 42 of 57 (74%) category 4c lesions, and 180 of 187 (96.3%) category 5 lesions were malignant. By using visual color stiffness to selectively upgrade category 3 and lack of stiffness to downgrade category 4a masses, specificity improved from 61.1% (397 of 650) to 78.5% (510 of 650) (P<.001); AUC increased to 0.962 (P=.005). Oval shape on SW elastographic images and quantitative maximum elasticity of 80 kPa (5.2 m/sec) or less improved specificity (69.4% [451 of 650] and 77.4% [503 of 650], P<.001 for both), without significant improvement in sensitivity or AUC. CONCLUSION: Adding SW elastographic features to BI-RADS feature analysis improved specificity of breast US mass assessment without loss of sensitivity.


Subject(s)
Elasticity Imaging Techniques/methods , Image Enhancement/methods , Ultrasonography, Mammary/methods , Adult , Aged , Aged, 80 and over , Europe , Female , Humans , Internationality , Middle Aged , Prospective Studies , Reproducibility of Results , Sensitivity and Specificity , Shear Strength , United States , Young Adult
3.
Cardiovasc Intervent Radiol ; 33(4): 828-34, 2010 Aug.
Article in English | MEDLINE | ID: mdl-19967366

ABSTRACT

The purpose was to evaluate ex-vivo a prototype of a novel biopsy canula under CT fluoroscopy-guidance in ventilated porcine lung explants in respiratory motion simulations. Using an established chest phantom for porcine lung explants, n = 24 artificial lesions consisting of a fat-wax-Lipiodol mixture (approx. 70HU) were placed adjacent to sensible structures such as aorta, pericardium, diaphragm, bronchus and pulmonary artery. A piston pump connected to a reservoir beneath a flexible silicone reconstruction of a diaphragm simulated respiratory motion by rhythmic inflation and deflation of 1.5 L water. As biopsy device an 18-gauge prototype biopsy canula with a lancet-like, helically bended cutting edge was used. The artificial lesions were punctured under CT fluoroscopy-guidance (SOMATOM Sensation 64, Siemens, Erlangen, Germany; 30mAs/120 kV/5 mm slice thickness) implementing a dedicated protocol for CT fluoroscopy-guided lung biopsy. The mean-diameter of the artificial lesions was 8.3 +/- 2.6 mm, and the mean-distance of the phantom wall to the lesions was 54.1 +/- 13.5 mm. The mean-displacement of the lesions by respiratory motion was 14.1 +/- 4.0 mm. The mean-duration of CT fluoroscopy was 9.6 +/- 5.1 s. On a 4-point scale (1 = central; 2 = peripheral; 3 = marginal; 4 = off target), the mean-targeted precision was 1.9 +/- 0.9. No misplacement of the biopsy canula affecting adjacent structures could be detected. The novel steerable biopsy canula proved to be efficient in the ex-vivo set-up. The chest phantom enabling respiratory motion and the steerable biopsy canula offer a feasible ex-vivo system for evaluating and training CT fluoroscopy-guided lung biopsy adapted to respiratory motion.


Subject(s)
Biopsy/instrumentation , Lung/diagnostic imaging , Lung/pathology , Tomography, X-Ray Computed/methods , Animals , Catheters , Diaphragm , Fluoroscopy/methods , Models, Animal , Models, Biological , Phantoms, Imaging , Respiratory Mechanics , Swine
4.
Cardiovasc Intervent Radiol ; 33(3): 583-5, 2010 Jun.
Article in English | MEDLINE | ID: mdl-19937025

ABSTRACT

We present a safe and quick technique for crossover embolization procedures of the internal iliac artery with high-profile guiding catheter systems, after a pull-through maneuver with establishment of a crossover catheter-snare system. The attached snare is used to stabilize and direct the guiding catheter.


Subject(s)
Aortic Aneurysm/therapy , Catheterization, Peripheral/methods , Embolization, Therapeutic/methods , Iliac Aneurysm/therapy , Angiography , Catheterization, Peripheral/instrumentation , Embolization, Therapeutic/instrumentation , Humans , Radiography, Interventional
5.
Eur Radiol ; 20(5): 1085-92, 2010 May.
Article in English | MEDLINE | ID: mdl-19890643

ABSTRACT

PURPOSE: To determine the value of a breast ultrasound (US) examination in addition to mammography in cases of American College of Radiology (ACR) tissue pattern III and IV in symptomatic women and women at risk. MATERIALS AND METHODS: A prospective cohort was initiated between 2001 and 2005 with a total of 59,514 patients and 102,744 mammograms. Documentation was available for 102,557 diagnostic procedures. Breast US was indicated in all women with ACR III and IV in addition to a suspicious clinical examination and in cases of masses and focal asymmetries in mammography. RESULTS: In total, 62,006 additional USs were performed, in which 116 mammographically and clinically occult breast cancers were diagnosed (detection rate: 1.9/1,000 examinations), while mammography alone (40,551 examinations) revealed 903 cancers (22.3/1,000). Of all 1,019 breast cancer findings, 12.8% were detected because of the combination of mammography and US. In the group with ACR III/IV, 15.9% of cancers were found by supplemental US compared with mammography alone. CONCLUSION: The addition of US to mammography vs. mammography alone resulted in a significant (P < 0.01) increase in breast cancer detection rate.


Subject(s)
Breast Neoplasms/diagnostic imaging , Quality Assurance, Health Care , Ultrasonography, Mammary , Adult , Aged , Algorithms , Breast Neoplasms/epidemiology , Chi-Square Distribution , Diagnosis, Differential , Female , Germany/epidemiology , Humans , Mammography , Middle Aged , Physical Examination , Prospective Studies , Sensitivity and Specificity
6.
Invest Radiol ; 44(3): 168-76, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19169143

ABSTRACT

OBJECTIVE: To evaluate the diagnostic efficacy (accuracy, sensitivity, specificity) of 1.0 M gadobutrol versus 0.5 M gadopentetate for the classification of lesions as either benign or malignant in patients with known or suspected liver lesions. METHODS AND MATERIALS: A multicenter, phase-III, randomized, interindividually controlled comparison study with blinded reader evaluation was performed to investigate the diagnostic efficacy of a bolus injection of 1.0 M gadobutrol compared with 0.5 M gadopentetate at a dose of 0.1 mmol Gd/kg BW. The imaging protocol included a dynamic 3D-evaluation, static conventional, and fat saturated T1-weighted sequences. MR datasets were evaluated by 3 independent radiologists. The standard of reference was defined by an independent truth panel (radiologist or hepatologist). The safety evaluation included adverse events, vital signs, and physical examination. RESULTS: A total of 497 of 572 patients were eligible for the final efficacy analysis. Noninferiority of gadobutrol-enhanced magnetic resonance imaging (MRI) for the classification of liver lesions was demonstrated on the basis of diagnostic accuracy determined by the on-site investigators (-0.098, 0.021) as well as for the average reader of the blinded evaluation (-0.096, 0.014) (95% confidence interval), compared with the predefined standard of reference. Very similar increases in sensitivity (ranging from approximately 10% to approximately 55%) and specificity (ranging from approximately 1% to approximately 18%) compared with precontrast MRI were also observed for the 2 contrast agent groups, with maximum differences of 4%.Very similar, low rates of adverse events were recorded for each of the 2 groups. No clinically relevant changes in vital signs or the results of the physical examination were observed in any patient. CONCLUSION: This study documents evidence for the noninferiority of a single i.v. bolus injection of 1.0 M gadobutrol (0.1 mmol/kg body weight) to 0.5 M gadopentetate (0.1 mmol/kg body weight) in the diagnostic assessment of liver lesions with contrast-enhanced MRI. The known excellent safety profile of gadobutrol was confirmed in this clinical trial and is similar to that of gadopentetate.


Subject(s)
Gadolinium DTPA , Image Enhancement/methods , Liver Neoplasms/epidemiology , Liver Neoplasms/pathology , Magnetic Resonance Imaging/statistics & numerical data , Organometallic Compounds , Contrast Media , Double-Blind Method , Europe/epidemiology , Female , Gadolinium DTPA/administration & dosage , Humans , Male , Middle Aged , Organometallic Compounds/administration & dosage , Prevalence , Reproducibility of Results , Sensitivity and Specificity
7.
Radiology ; 247(1): 273-85, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18372471

ABSTRACT

PURPOSE: To prospectively determine diagnostic performance and safety of contrast material-enhanced (CE) magnetic resonance (MR) angiography with 0.1 mmol per kilogram of body weight gadobenate dimeglumine for depiction of significant steno-occlusive disease (> or =51% stenosis) of renal arteries, with digital subtraction angiography (DSA) as reference standard. MATERIALS AND METHODS: This multicenter study was approved by local institutional review boards; all patients provided written informed consent. Patient enrollment and examination at centers in the United States complied with HIPAA. Two hundred ninety-three patients (154 men, 139 women; mean age, 61.0 years) with severe hypertension (82.2%), progressive renal failure (11.3%), and suspected renal artery stenosis (6.5%) underwent CE MR angiography with three-dimensional spoiled gradient-echo sequences after administration of 0.1 mmol/kg gadobenate dimeglumine at 2 mL/sec. Anteroposterior and oblique DSA was performed in 268 (91.5%) patients. Three independent blinded reviewers evaluated CE MR angiographic images. Sensitivity, specificity, and accuracy of CE MR angiography for detection of significant steno-occlusive disease (> or =51% vessel lumen narrowing) were determined at segment (main renal artery) and patient levels. Positive and negative predictive values and positive and negative likelihood ratios were determined. Interobserver agreement was analyzed with generalized kappa statistics. A safety evaluation (clinical examination, electrocardiogram, blood and urine analysis, monitoring for adverse events) was performed. RESULTS: Of 268 patients, 178 who were evaluated with MR angiography and DSA had significant steno-occlusive disease of renal arteries at DSA. Sensitivity, specificity, and accuracy of CE MR angiography for detection of 51% or greater stenosis or occlusion were 60.1%-84.1%, 89.4%-94.7%, and 80.4%-86.9%, respectively, at segment level. Similar values were obtained for predictive values and for patient-level analyses. Few CE MR angiographic examinations (1.9%-2.8%) were technically inadequate. Interobserver agreement for detection of significant steno-occlusive disease was good (79.9% agreement; kappa = 0.69). No safety concerns were noted. CONCLUSION: CE MR angiography performed with 0.1 mmol/kg gadobenate dimeglumine, compared with DSA, is safe and provides good sensitivity, specificity, and accuracy for detection of significant renal artery steno-occlusive disease.


Subject(s)
Angiography, Digital Subtraction , Contrast Media , Magnetic Resonance Angiography , Meglumine/analogs & derivatives , Organometallic Compounds , Renal Artery Obstruction/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Renal Artery/diagnostic imaging , Renal Artery/pathology , Renal Artery Obstruction/diagnostic imaging , Sensitivity and Specificity
8.
J Vasc Interv Radiol ; 18(10): 1241-8, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17911514

ABSTRACT

PURPOSE: To characterize a new protocol of computed tomographic (CT) fluoroscopy-guided biopsy of the lung and upper abdomen to minimize the intervention time, complication rate, and exposure to ionizing radiation for both the patient and the radiologist. MATERIALS AND METHODS: Fifty patients (23 women, 27 men; mean age, 64.3 years; age range, 36-83 years) with lung (n = 41) or upper abdomen (n = 9) nodules 15 mm or smaller underwent CT fluoroscopy-guided biopsy from November 2005 to October 2006. The mean nodule diameter was 12.6 mm (range, 8-15 mm), the mean depth to skin was 57.3 mm (range, 20-114 mm), and the mean depth of nodules from pleura and/or peritoneum was 18.9 mm (range, 1-77 mm). Histopathologic evaluation of samples was performed on the day of the procedure. A CT fluoroscopy-guided biopsy protocol was established as follows: (a) native CT with breath-holding at an intermediate respiration level, (b) selection of section position with target nodule and insertion of an 18-gauge coaxial biopsy needle extrapleurally and/or extraperitoneally virtually targeting at nodule, (c) start of CT fluoroscopy (130 kVp, 30 mAs, 5-mm-thick sections) at inspiration level with the patient expiring, (d) stop of CT fluoroscopy when the target nodule reaches the section position, short breath-hold, needle advancement to the target nodule, (e) control of needle position with CT fluoroscopy, and (f) biopsy. RESULTS: The mean total table time was 23.8 minutes (range, 15-41 minutes), the mean duration of CT fluoroscopy was 8.2 seconds (range, 4-23 seconds), and the mean duration of breath-holding--including needle insertion to target nodule and control CT fluoroscopy--was 10.3 seconds (range, 5-15 seconds). There were three minor pneumothoraces that required no further intervention, seven minor pulmonary hemorrhages, three moderate pulmonary hemorrhages with hemoptysis, and one moderate liver hematoma. There were no major complications. The diagnostic accuracy of biopsy samples was 96%. CONCLUSIONS: The presented modification of CT fluoroscopy-guided biopsy of mobile pulmonary and upper abdominal lesions is a rapid and safe procedure, requiring only short exposure to ionizing radiation.


Subject(s)
Abdominal Neoplasms/diagnostic imaging , Biopsy, Needle/methods , Lung Neoplasms/diagnostic imaging , Radiography, Interventional , Respiration , Tomography, X-Ray Computed , Abdominal Neoplasms/pathology , Abdominal Neoplasms/physiopathology , Adult , Aged , Aged, 80 and over , Biopsy, Needle/adverse effects , Female , Fluoroscopy , Hematoma/etiology , Hemoptysis/etiology , Hemorrhage/etiology , Humans , Liver Diseases/etiology , Lung Diseases/etiology , Lung Neoplasms/pathology , Lung Neoplasms/physiopathology , Male , Middle Aged , Pneumothorax/etiology , Predictive Value of Tests , Prospective Studies , Severity of Illness Index , Time Factors
9.
Cardiovasc Intervent Radiol ; 30(3): 376-82, 2007.
Article in English | MEDLINE | ID: mdl-17278036

ABSTRACT

The objective of the study was to prove the value of single-dose contrast-enhanced magnetic resonance angiography [three-dimensional (3D) ceMRA] in abdominal and iliac arteries versus the reference standard intra-arterial digital subtraction angiography (i.a.DSA) when indicating a therapy. Patients suspected of having abdominal or iliac artery stenosis were included in this study. A positive vote of the local Ethics Committe was given. After written informed consent was obtained, 37 patients were enrolled, of which 34 were available for image evaluation. Both 3D ceMRA and i.a. DSA were performed for each patient. The dosage for 3D ceMRA was 0.1 mmol/kg body weight in a 1.5-T scanner with a phased-array coil. The parameters of the 3D-FLASH sequence were as follows: TR/TE 4.6/1.8 ms, effective thickness 3.5 mm, matrix 512 x 200, flip angle 30 degrees , field of view 420 mm, TA 23 s, coronal scan orientation. Totally, 476 vessel segments were evaluated for stenosis degree by two radiologists in a consensus fashion in a blinded read. For each patient, a therapy was proposed, if clinically indicated. Sensitivity, specificity, positive and negative predictive values, and accuracy for stenoses > or = 50% were 68%, 92%, 44%, 97%, and 90%, respectively. In 13/34 patients, a discrepancy was found concerning therapy decisions based on MRA findings versus therapy decisions based on the reference standard DSA. The results showed that the used MRA imaging technique of abdominal and iliac arteries is not competitive to i.a. DSA, with a high rate of misinterpretation of the MRAs resulting in incorrect therapies.


Subject(s)
Angiography, Digital Subtraction/methods , Aortic Diseases/diagnosis , Aortography/methods , Arterial Occlusive Diseases/diagnosis , Contrast Media , Gadolinium DTPA , Iliac Artery , Image Processing, Computer-Assisted/methods , Magnetic Resonance Angiography/methods , Aged , Angioplasty, Balloon , Aortic Diseases/therapy , Blood Vessel Prosthesis Implantation , Female , Humans , Iliac Artery/pathology , Male , Middle Aged , Observer Variation , Predictive Value of Tests , Sensitivity and Specificity , Stents , Triiodobenzoic Acids
10.
Abdom Imaging ; 32(3): 304-9, 2007.
Article in English | MEDLINE | ID: mdl-16955377

ABSTRACT

This article focuses on stent placement in mesenteric arteries in patients with the rare diagnosis of chronic mesenteric ischemia. We present a survey from the initial stage of recognition of this gastrointestinal disorder and its manifestations to treatment by stenting to avoid further ischemic episodes and bowel infarction and necrosis. The advantages of stent placement in splanchnic arteries are discussed in comparison to open surgical revascularization.


Subject(s)
Mesenteric Arteries , Mesenteric Vascular Occlusion/therapy , Stents , Chronic Disease , Humans , Mesenteric Vascular Occlusion/diagnostic imaging , Radiography, Interventional
11.
Eur J Radiol ; 61(2): 315-23, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17074459

ABSTRACT

PURPOSE: Prospective evaluation of diagnostic accuracy of single field-of-view contrast-enhanced MR Angiography (ceMRA) with 1.0M gadobutrol compared to intraarterial DSA in body arteries. MATERIALS AND METHODS: In an European multicenter study 179 patients underwent ceMRA and DSA. For each indication five prospectively defined vessel segments were evaluated by local investigators onsite and by three site-independent blinded readers (BR) independently. RESULTS: The agreement between ceMRA and DSA diagnosis was statistically significant in the onsite (96.6%) and blinded reader (86.6-90.2%) evaluation. Sensitivity, specificity, accuracy, positive (PPV) and negative predictive values (NPV) for detection of relevant stenosis (>50%) were calculated for the right and left internal carotid arteries, and common and external iliac arteries: Sensitivity was 95-98% (onsite) and 76-96% (BR), specificity 94-96% (onsite) and 86-94% (BR), accuracy 96% (onsite) and 87-93% (BR), NPV 98-99% (onsite) and 84-98% (BR), and PPV 79-93% (onsite) and 44-91% (BR), respectively. CONCLUSION: CeMRA of body arteries using 1.0M gadobutrol provides diagnostic information comparable to intraarterial DSA.


Subject(s)
Angiography, Digital Subtraction , Arteries/pathology , Magnetic Resonance Angiography/methods , Adult , Aged , Aged, 80 and over , Constriction, Pathologic/diagnosis , Contrast Media , Gadolinium , Humans , Male , Middle Aged , Organometallic Compounds , Prospective Studies , Sensitivity and Specificity , Single-Blind Method
12.
J Vasc Interv Radiol ; 17(4): 637-43, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16614146

ABSTRACT

PURPOSE: To analyze the immediate and midterm success of stenting of mesenteric arteries by a monorail technique in patients with chronic mesenteric ischemia. MATERIALS AND METHODS: In this prospective case series, 19 patients (11 male, 8 female; mean age, 62.9 +/- 10.4 y; range, 36-82 y) with 23 symptomatic stenoses of mesenteric arteries were treated with stent placement by a monorail technique in a radiologic intervention center over a period of 4.5 years. Clinical examinations and duplex sonography were used to evaluate the stents' patency and clinical success. Kaplan-Meier graphs were calculated to analyze the patency and freedom-from-symptom rate. RESULTS: Initial technical success rate was 22/23 (96%). Mean follow-up was 17 months (range, 1-58 mo). Primary patency and primary clinical success rates were 82% and 78%, respectively. According to Kaplan-Meier tables, the patency rates were 96%, 87%, 76%, and 61% at 0, 1, 15, and 24 months, respectively, and the freedom-from-symptom rates were 95%, 90%, 72%, and 54% at 0, 1, 24, and 30 months, respectively. No peri-interventional complications occurred. Two patients died of cardiac failure in the hospital within 30 days after intervention; deaths were not related to the intervention. CONCLUSIONS: Stent placement by a monorail technique in mesenteric arteries is an effective and safe treatment for symptomatic stenoses in patients with chronic mesenteric ischemia after a mean follow-up of 17 months.


Subject(s)
Mesenteric Vascular Occlusion/therapy , Stents , Adult , Aged , Aged, 80 and over , Angiography, Digital Subtraction , Female , Humans , Male , Mesenteric Arteries , Mesenteric Vascular Occlusion/diagnostic imaging , Middle Aged , Prospective Studies , Radiography, Interventional , Treatment Outcome , Ultrasonography, Doppler, Duplex , Ultrasonography, Interventional , Vascular Patency
13.
Eur J Radiol ; 58(3): 411-5, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16466674

ABSTRACT

OBJECTIVE: To evaluate fat-suppressed (FS) proton-density-weighted (PDw) turbo spin-echo (TSE) magnetic resonance imaging for the detection of anterior and posterior cruciate ligament lesions in comparison to arthroscopy. MATERIALS AND METHODS: In a prospective study 31 knee joints were imaged on a 1.5T MR scanner (Vision, Siemens, Erlangen) prior to arthroscopy using following sequences: (a) sagittal FS-PDw/T2w TSE (TR/TE: 4009/15/105 ms); (b) sagittal PDw/T2w TSE (TR/TE:3800/15/105 ms). Further imaging parameters: slice thickness 3mm, FOV 160 mm, matrix 256 x 256. A total of 62 anterior and posterior cruciate ligaments (ACL/PCL) were evaluated, standard of reference was arthroscopy. Sensitivity, specificity, positive (ppv) and negative predictive value (npv) and accuracy were calculated. RESULTS: Twenty-one cruciate ligament ruptures were detected in arthroscopy, 19 ACL- and 2 PCL-ruptures (on MRI 34/124, 25/62 ACL, 9/62 PCL lesions). For all four sequences in the 31 patients with arthroscopic correlation sensitivity, specificity, ppv, npv and accuracy were 86%, 98%, 95%, 93% and 94% for detection of tears, and 84%, 100%, 100%, 80% and 90% for ACL-ruptures respectively. The two PCL-ruptures were true positive in all sequences, one intact PCL was diagnosed as torn (false positive). CONCLUSIONS: Fat-suppressed PDw/T2w TSE-MR sequences are comparable to PDw TSE sequences for the detection of ACL/PCL-lesions.


Subject(s)
Anterior Cruciate Ligament/pathology , Arthroscopy/methods , Image Enhancement/methods , Joint Diseases/diagnosis , Magnetic Resonance Imaging/methods , Posterior Cruciate Ligament/pathology , Adolescent , Adult , Aged , Female , Humans , Knee Joint/pathology , Male , Middle Aged , Observer Variation , Predictive Value of Tests , Prospective Studies , Reproducibility of Results , Rupture/diagnosis , Sensitivity and Specificity
14.
J Vasc Interv Radiol ; 16(7): 903-10, 2005 Jul.
Article in English | MEDLINE | ID: mdl-16002499

ABSTRACT

PURPOSE: To test the efficacy of limited oral administration of the new leflunomide analogue FK778 for suppression of neointima proliferation in a double-injury restenosis model in the rat. MATERIALS AND METHODS: For induction of aortic lesions, silicon cuffs were placed operatively around the infrarenal aortas of Lewis rats. After 21 days, the aortic cuffs were removed and the lesions were dilated with 2-F Fogarty catheters inserted via the left common carotid artery. The novel immunosuppressant FK778 was administered at a dose of 5 mg/kg body weight (group 1) or 15 mg/kg body weight (group 2) in a total of 38 animals. For both doses, three different periinterventional time periods, each with a 5-day course of oral FK778, were defined as follows: (i) days -2 to 2, (ii) days 1-5, and (iii) days 7-11, with six or seven rats in each group. After 3 weeks, intima/media ratios were assessed morphometrically and immunohistochemistry for quantification of intimal alpha-actin expression was performed. RESULTS: In both dose groups, there was a trend toward inhibition of neointima formation when the 5-day course of FK778 was started before or 1 day after the intervention. However, in the lower-dose group, inhibition of neointima was not statistically significant regardless of the time frame of treatment (groups 1a-c). With the higher dose, suppression of intimal hyperplasia was significant when FK778 was administered between days 1 and 5 after angioplasty (group 2b; P<.01). Expression of alpha-actin in the intima of FK778-treated rats was significantly reduced when the drug was started 2 days before angioplasty in group 1a (P<.05) or 1 day after angioplasty in both dosage groups (group 1b, P<.01; group 2b, P<.05). CONCLUSION: In the double-injury rat model presented, balloon-mediated proliferation of smooth muscle cells in the intima with consecutive intimal thickening was influenced by FK778 in a dose-dependent manner. However, long-term studies are needed to exclude a delay of vascular healing in this particular model.


Subject(s)
Immunosuppressive Agents/administration & dosage , Isoxazoles/administration & dosage , Tunica Intima/drug effects , Actins/analysis , Administration, Oral , Alkynes , Angioplasty, Balloon , Animals , Disease Models, Animal , Hyperplasia , Immunohistochemistry , Male , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/pathology , Nitriles , Rats , Rats, Inbred Lew , Tunica Intima/pathology
15.
J Endovasc Ther ; 12(3): 318-31, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15943507

ABSTRACT

PURPOSE: To characterize a new rat model of restenosis for evaluation of local or systemic drug strategies. METHODS: Arterial lesions were induced by placement of silicone cuffs around the aorta of Lewis rats. After 21 days, the cuffs were removed, and a subgroup of rat aortas was subjected to secondary balloon injury. Remodeling of wall compartments and cell kinetics were assessed morphometrically at 3, 7, 14, 21, and 28 days after the single and double-injury approaches. Immunohistochemistry was used to assess the distribution of macrophages, smooth muscle cells, and proliferating cells within the layers of the arterial wall in the experimental groups versus sham-operated and untreated controls. RESULTS: After cuff placement, the adventitia initially undergoes significant enlargement, while the media shows a reduction in relative thickness. Accumulation of cells within the adventitia at 3 and 7 days is followed by a marked decline in cell density at 14 days, with simultaneously increasing cell numbers in the intima. At this time, activated macrophages are detected in the adventitia, indicating chronic inflammation. Following cuff placement, mild intimal hyperplasia develops. In the double-injury model, extensive neointimal hyperplasia forms rapidly, with a peak at 14 days. CONCLUSIONS: This new double-injury model is technically easy, and multiple experiments can be accrued in short periods of time. It provides an additional platform to identify new targets and strategies for the prophylaxis of postangioplasty restenosis.


Subject(s)
Aorta, Abdominal/pathology , Arterial Occlusive Diseases/pathology , Actins/metabolism , Angioplasty, Balloon/adverse effects , Animals , Aorta, Abdominal/injuries , Aorta, Abdominal/metabolism , Arterial Occlusive Diseases/metabolism , Arterial Occlusive Diseases/therapy , Cell Count , Disease Models, Animal , Follow-Up Studies , Hyperplasia/pathology , Immunohistochemistry , Macrophages/pathology , Muscle, Smooth, Vascular/pathology , Rats , Rats, Inbred Lew , Recurrence , Severity of Illness Index , Tunica Intima/metabolism , Tunica Intima/pathology
16.
J Endovasc Ther ; 12(3): 332-42, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15943508

ABSTRACT

PURPOSE: To evaluate the efficacy of limited short-term systemic administration of rapamycin to prevent neointimal intimal hyperplasia (NIH) in a double-injury rat model of restenosis. METHODS: Aortic lesions were induced by perivascular placement of silicone cuffs around the aorta of 36 Lewis rats. After 3 weeks, the cuffs were removed, and the vessels were subjected to secondary balloon injury. Rapamycin (sirolimus) was intravenously administered for 5 days in dosages of 0.5 or 2 mg/kg/d beginning at various time points relative to the balloon injury: (1) days -2 to +2, (2) days 1 to 5, or (3) days 7 to 11. For each treatment period, 6 rats received the 5-day course of the lower or higher dose of rapamycin. Eight rats served as controls undergoing 2-stage injury without rapamycin treatment. Morphometry and immunohistochemistry were performed at 21 days after angioplasty. RESULTS: NIH and intimal alpha-actin expression were inhibited by both dosages when treatment started 2 days before or 1 day after angioplasty. Results were statistically significant for the lower dose when started 1 day after angioplasty (p < 0.01) and for the higher dose when initiated 2 days before the intervention (p < 0.05). Treatment commencing at 7 days did not reduce NIH in either dosage group. CONCLUSIONS: In a double-injury rat model, NIH can be inhibited by short-term systemic rapamycin, but suppression of early cell migration and proliferation is pivotal. A limited peri-interventional antiproliferative therapy may be of value as an adjunct to control restenosis after balloon angioplasty and/or stenting.


Subject(s)
Aorta, Abdominal/pathology , Arterial Occlusive Diseases/prevention & control , Immunosuppressive Agents/therapeutic use , Sirolimus/therapeutic use , Tunica Intima/pathology , Actins/metabolism , Angioplasty, Balloon/adverse effects , Animals , Aorta, Abdominal/injuries , Aorta, Abdominal/metabolism , Arterial Occlusive Diseases/etiology , Arterial Occlusive Diseases/pathology , Cell Count , Disease Models, Animal , Dose-Response Relationship, Drug , Follow-Up Studies , Hyperplasia/pathology , Hyperplasia/prevention & control , Immunosuppressive Agents/administration & dosage , Male , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/pathology , Rats , Rats, Inbred Lew , Secondary Prevention , Sirolimus/administration & dosage , Time Factors , Treatment Outcome , Tunica Intima/drug effects , Tunica Intima/metabolism
17.
Eur Radiol ; 13(9): 2103-14, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12928960

ABSTRACT

The purpose of this study was to compare moving-table three-dimensional contrast-enhanced magnetic resonance angiography (CE MRA), using 1.0-mol gadobutrol, with intra-arterial digital subtraction angiography (i.a. DSA) for evaluation of pelvic and peripheral arteries in patients with peripheral arterial occlusive disease. A total of 203 patients were examined in a prospective, multi-centre study at 1.0/1.5 T. Ten vessel segments of one leg were evaluated on-site and by three independent blinded reviewers off-site. One hundred eighty-two patients were evaluable in blinded reading. For pelvis and thigh, there was statistically significant diagnostic agreement between CE MRA and i.a. DSA on-site (94%) and off-site (86-88%). Overall, for detection of clinically significant stenoses, 93% sensitivity and 90% specificity were achieved in on-site evaluation, with 71-76 and 87-93% off-site; for detection of occlusion, sensitivity and specificity on-site were 91 and 97%, with 75-82 and 94-98% off-site. Evaluation was more sensitive on-site than off-site for detection of stenoses and occlusion, whereas specificity was similar. The CE MRA with 1.0-mol gadobutrol gave results comparable to those of i.a. DSA for the larger arteries of pelvis and thigh. Results for calf arteries were compromised by spatial resolution and technical limitations.


Subject(s)
Angiography, Digital Subtraction , Arterial Occlusive Diseases/diagnosis , Magnetic Resonance Angiography/methods , Peripheral Vascular Diseases/diagnosis , Contrast Media , Double-Blind Method , Female , Humans , Image Enhancement/methods , Leg/blood supply , Male , Middle Aged , Organometallic Compounds , Pelvis/blood supply , Prospective Studies , Sensitivity and Specificity
18.
J Vasc Interv Radiol ; 14(1): 41-51, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12525585

ABSTRACT

PURPOSE: To report a prospective study to evaluate safety, effectiveness, and midterm patency of self-expanding stent-grafts in patients with femoropopliteal occlusive disease. MATERIALS AND METHODS: Sixty-three Hemobahn stent-grafts were used in 52 patients for treatment of medium- or long-segment (>3 cm) occlusions (82.7%) and stenoses (17.3%) of the femoropopliteal artery. The mean length of vessel segments covered was 10.9 cm +/- 5.13. Follow-up with documentation of clinical symptoms, assessment of Rutherford clinical stage of peripheral vascular disease, and color-coded duplex sonography was performed at discharge, at 1, 3, 6, 12, 18, and 24 months after implantation, and yearly thereafter. Mean follow-up duration was 23.8 months +/- 6.9 (range, 8-36 mo). Follow-up data at 12 and 24 months after treatment were available for 47 of 52 (90.4%) and 31 of 52 patients (59.6%), respectively. RESULTS: Device implantation was technically successful in all 52 patients, yielding an overall technical success rate of 100%. Procedure-related complications were observed in 12 of 52 patients (23.1%) and consisted of distal embolization (n = 4, 7.7%), minor groin hematoma (n = 7, 13.5%), and arteriovenous fistula (n = 1, 1.9%), but prolonged hospitalization and further medical, interventional, or surgical measures were not required. Stent-graft placement induced an initial improvement of the mean resting ankle-brachial index from 0.54 +/- 0.12 to 0.89 +/- 0.14 (P <.01). Primary patency rates at 12 and 24 months were 78.4% +/- 5.8 and 74.1% +/- 6.2, respectively. Primary assisted patency rates were 82.4% +/- 5.3 at 12 months and 80.3% +/- 5.6 at 24 months. Secondary patency rates at 12 and 24 months were 88.3% +/- 4.5 and 83.2% +/- 5.5, respectively. There was no significant difference (log-rank test, P >.3) between primary patency rates in patients grouped according to lengths of implanted grafts (ie, length of the treated lesions). CONCLUSION: Endovascular placement of Hemobahn stent-grafts for percutaneous treatment of medium- to long-segment high-grade stenoses and occlusions of the femoropopliteal artery is a safe procedure with excellent initial success rates and promising midterm results.


Subject(s)
Arterial Occlusive Diseases/therapy , Blood Vessel Prosthesis Implantation/methods , Femoral Artery , Intermittent Claudication/therapy , Popliteal Artery , Stents , Aged , Aged, 80 and over , Angiography, Digital Subtraction , Angioplasty, Balloon , Arterial Occlusive Diseases/complications , Arterial Occlusive Diseases/diagnostic imaging , Female , Femoral Artery/surgery , Humans , Intermittent Claudication/etiology , Male , Middle Aged , Popliteal Artery/surgery , Prospective Studies , Treatment Outcome , Vascular Patency
20.
Article in English | MEDLINE | ID: mdl-9561352

ABSTRACT

The analysis of heart rate (HR) variability offers a noninvasive method to investigate autonomic nervous system activity in comatose patients. We analyzed three components of the HR variability in a group of comatose patients: the low-frequency band (LF), representing mainly sympathetic influence, the mid-frequency band (MF), representing sympathetic and parasympathetic influence, and the high-frequency band (HF), representing the parasympathetic influence. A value for sympathovagal balance was defined as LF/HF and MF/HF ratio. Moreover, the skin conductance level (SCL) and the skin conductance resistance (SCR) variability were recorded. The patient group consisted of 22 patients with traumatic brain injuries. Coma depth was assessed by the Glacow Coma Scale and artifact-free HR, SCL, and SCR were measured 75 times in the patient group. The results documented a significant gain in sympathetic nervous system activity corresponding with the state of emerging from coma. This gain was most pronounced in the HF component of the HR and in the sympathovagal balance between LF/HF. The findings in SCL and SCR variability endorsed this result. It is concluded that emerging from coma is accompanied by an increasing influence of the sympathetic nervous system on HR control. This leads to a change in the sympathovagal balance, i.e., a reintegration of parasympathetic and sympathetic activity.


Subject(s)
Autonomic Nervous System/physiology , Coma/physiopathology , Electrophysiology/methods , Heart Rate/physiology , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Statistics, Nonparametric
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