Thomas Diebold

Magnetic resonance imaging in the diagnosis of acute injured distal tibiofibular syndesmosis.

RATIONALE AND OBJECTIVES This study assessed the diagnostic potential of magnetic resonance imaging for the evaluation of the tibiofibular syndesmosis. METHODS A total of 38 patients with an acute ankle trauma and clinical suspicion of a syndesmotic tear were prospectively studied with conventional plain film radiography and magnetic resonance imaging. Magnetic resonance imaging studies included plain T1-weighted (T1-w) and T2-weighted (T2-w) sequences and contrast-enhanced T1-w sequences 0 to 3 days after trauma. All images were read by two independent radiologists before surgical intervention. Sensitivity and specificity were determined for the two observers and the concordance of the two observers were calculated using the interobserver analysis (Kappa-Test). Intraoperative inspection (n = 21) revealed rupture of the anterior tibiofibular ligament (ATIF) in 15 patients, intact ATIF in 6 patients, and intact posterior tibiofibular ligament (PTIF) in 21 cases. Clinical and follow-up examinations revealed an intact syndesmotic complex in another 17 patients. RESULTS Primary diagnostic criteria for diagnosing a ligamentous tear included tibiofibular diastasis in conventional plain films; nonvisualization of the ATIF; an abnormal course, a wavy, irregular contour of the ligament; increased signal intensity of the ligament in T2-w sequences, in plain T1-w sequence, and marked enhancement in T1-w after contrast. Important secondary signs were defined as joint fluid in the tibiofibular space and prolapse of interspace fat. Highest diagnostic accuracy was achieved if three or more diagnostic criteria could be visualized. Both readers performed best with the enhanced T1-weighted and the T2-weighted images in transverse orientation. The interobserver analysis resulted in high concordance: Kappa = 0.9 (confidence interval: 0.76 to 1.00) for all patients, and in Kappa = 0.76 (confidence interval: 0.45 to 1.0) for surgically treated patients. CONCLUSIONS Magnetic resonance imaging of the syndesmotic complex is a highly sensitive and specific tool for the pretherapeutic-evaluation of syndesmotic injury.

Evaluation of the Stereotactic 8g Vacuum-assisted Breast Biopsy in the Histologic Evaluation of Suspicious Mammography Findings (bi-rads Iv)

Purpose:The purpose of this study was to evaluate the potential of the new 8G stereotactic vacuum-assisted breast biopsy (ST-driver, Mammotome; Ethicon Endosurgery) in the histologic evaluation of BI-RADS IV microcalcifications. Materials and Methods:Fifty-eight patients with 61 mammographic BI-RADS IV microcalcifications underwent stereotactic vacuum-assisted breast biopsy (SVAB). The new 8G system was mounted on the ST driver, which was formerly used only with the handheld version under sonographic guidance. The evaluation criteria for each biopsy were minimally invasive and operative histologies, the time needed for biopsy, the amount of bleeding, number of rotations and specimen, the degree of resection, and the complications. Results:Fifty-eight of 61 biopsies were technically successful because ≥50% were resected (29 × 100%, 8 × 90%, 5 × 80%, 6 × 70%, 3 × 50%, 3 × 0%). In 7 cases with representative biopsies of segmental suspicious microcalcifications, the degree of resection could not be exactly measured. All but 2 biopsies were performed without clinically relevant complications and after gaining enough specimens (Ø 12.6 specimen, 1.85 rotations). Those 2 patients showed evidence of severe bleeding into the breast tissue and operative revision had to be performed (3.5%). The size of intramammary hematoma was measurable in 27 biopsies and showed a range from 0.5 to 5 cm (Ø 2.7 cm). The average external bleeding was still low with 16 mL (5–80 mL). In 3 of 61 lesions, it was not possible to gain representative tissue as a result of displacement of the lesion after introducing or shooting the needle. The average time needed for all biopsies was 28.2 minutes for all but 5 very complicated biopsies, which took 16.1 minutes. The histologic findings with further operative workup were: 10 ductal carcinomas in situ (DCIS), 4 atypical ductal hyperplasias, 1 atypical lobular hyperplasias (ALH), 3 lobular carcinomas in situ (LCIS), and 6 invasive ductal carcinomas. In 7 of 12 of the initial DCIS histologies, the operative histology was also DCIS, whereas in 4 of 12, no residual malignant tumor was found. In 1 of 12 patients with an initial DCIS histology, operative histology revealed invasive ductal cancer (8.3%). The cases with lobular lesions (ALH, LCIS) did not show any evidence for residual tissue in the operative workup. Most frequent benign histologies were mastopathy (13), ductal hyperplasia (9), fibroadenoma (8), and sclerosing adenosis (5). The control examinations (maximum 1 year) did not show any signs for a false-negative biopsy. Conclusion:The 11-G SVAB has proven to be a perfect adjunct to the existing breast biopsy methods. The new 8G SVAB speeds up the method when used for the same size of lesions and enables the user to representatively biopsy lesions up to 3 cm in diameter. The method is still minimally invasive; however, the amount of hematomas as well as clinically relevant complications is increased.

MRI in pre- and postoperative assessment of tracheal stenosis due to pulmonary artery sling

Objective To evaluate the potential of MRI in the assessment of tracheal stenosis due to tracheal or vascular malformations, 45 children with severe respiratory distress were examined prospectively during a period of 1 year. Five of these children had tracheal stenosis due to a sling left pulmonary artery (SLPA). Materials and Methods Magnetic resonance examinations of the anesthetized children were performed with a 1.5 T Siemens MR imager using electro-cardiographically gated Tl-weighted SE sequences in transverse and sagittal slice orientations. Slice thickness was 3 mm and each sequence was repeated after shifting the slice position by 1 mm. Monitoring during the examinations included ECG, oscillatory blood pressure, respiratory rate, and oxygen concentration. Magnetic resonance findings were compared with esophagography, selective pulmonary angiography, bronchoscopy, Doppler sonography, and surgery. All examinations were repeated after surgical therapy to assess the improvement in tracheal stenoses and the patency of the ligated and reimplanted left pulmonary arteries. Results Magnetic resonance imaging clearly revealed the course of the SLPA and its topographic relationship to the trachea as well as the coexistence of cardiovascular and tracheobronchial or esophageal malformations. The degree and length of tracheal stenoses, which were measured in the pre- and postoperative axial slices and graphically displayed, as well as the angles of the right and left main stem bronchi, could be accurately determined. Conclusion Magnetic resonance imaging in combination with bronchoscopy yielded the necessary and sufficient information for diagnosis and aided the surgeon in planning operative strategy and in postoperative follow-up.

Entzündliche Erkrankungen des Pharynx : Bildgebende Befunde und diagnostische Strategie

ZusammenfassungZielsetzung. Ziel der Arbeit ist die Vorstellung bildgebender Befunde entzündlicher Pharynx-Erkrankungen auf Basis der CT- und MRT-Diagnostik und interventioneller Techniken. Methodik. Die bildgebende Diagnostik bei entzündlichen Erkrankungen des Pharynx beruht im Wesentlichen auf dem Einsatz der kontrastmittelverstärkten Computertomographie sowie optimierter MRT-Sequenzprotokolle. Dabei ist die Kenntnis der bildmorphologischen Befunde und der Morphologie von Komplikationen entscheidend. Ergebnisse. Der Vorteile der bildgebenden Diagnostik, CT und MRT, liegen in der Möglichkeit, unter der Schleimhaut gelegene, entzündliche Veränderungen zu diagnostizieren sowie lokale oder generalisierte Komplikationen zu evaluieren. Die häufigsten Entitäten stellen dabei parapharyngeal gelegene Abszesse oder phlegmonöse Entzündungen dar. Die Computertomographie erweist sich als vorteilhaft aufgrund der raschen Verfügbarkeit und der präzisen Identifikation flüssigkeits- und lufthaltiger Strukturen. Die MRT besticht durch die verbesserte Weichteilkontrastierung sowie die nicht invasive Flussanalyse mittels MR-Angiographie (MRA). Schlussfolgerungen. Die Spiral-CT sowie die MRT und MRA erlauben wesentliche diagnostische Informationen bei Entzündungen des Pharynx und komplizierten Verläufen.AbstractPurpose. To demonstrate imaging findings in inflammatory diseases of the pharynx and possible complications. Material and methods. Radiologic imaging of the pharynx is based on the use of conventional X-ray films, computed tomography and magnetic resonance imaging, plain and contrast enhanced. Results. The advantages of cross sectional imaging techniques like CT and MRT lie in the possibility to diagnose submucosal disease and localized as well as general complications. Most frequently abscesses and phlegmonous diseases have to be diagnosed. CT proves advantageous due to its fast imaging protocol and the widely availability. MRI is superior due to its superior soft tissue contrast and the multiplanar imaging. Conclusion. Spiral-CT and MRI mean valuable diagnostic tools for the evaluation of inflammatory diseases of the pharynx and possible complications.

Imaging and Interventional Diagnostics of the Breastmammary Gland Using X-Ray Mammography, Mamma Sonography and MR Mammography

This chapter will serve as an introduction to the relevant imaging diagnostics of the breast – i.e. X-ray mammography, sonography, and magnetic resonance (MR) mammography – so that the reader gets a first, basic understanding of the topic. Furthermore, a large number of pathognomonic findings will contribute to enabling deeper insight into the topic.

Bildgebende und Interventionelle Diagnostik der Brustdrüse mittels Röntgen-Mammographie, Mamma-Sonographie und MR-Mammographie

Dieses Kapitel soll Ihnen fur alle in der bildgebenden Diagnostik der Mamma masgeblich eingesetzten Verfahren – also der Rontgen-Mammographie, der MR-Mammographie und der Mamma-Sonographie – zunachst ein grundlegendes Verstandnis und daruber hinaus an einer Vielzahl pathognomonischer Befunden auch den weiteren Einstieg in die Thematik ermoglichen.

Die Rolle der Radiologie in der Diagnostik und Therapie des zentralen Gallengangskarzinoms

Untersuchungsverfahren der diagnostischen und interventionellen Radiologie beruhen auf dem Einsatz der farbkodierten und kontrastverstärkten Dopplersonographie, der Spiral-Computertomographie, der Magnetresonanzverfahren (MR), wie der MR-Tomographie (MRT) und MR-Cholangio-Pankreatikographie (MRCP), sowie der perkutanen Cholangiographie (PTC). Interventionelle Verfahren mit therapeutischer Option beinhalten den Einsatz der PTCD (Drainage), sowie angiographischer Verfahren mit Embolisationstechniken zur Induktion einer Leberregeneration.Die moderne bildgebende Diagnostik erlaubt die exakte Bestimmung der Höhe der Obstruktion und der Ausdehnung des Tumors entlang der intrahepatischen Gallenwege. Mit der MRCP gelingt der Nachweis einer malignen Gallenwegsstenose mit einer Sensitivität von 86% und einer Spezifität von 98%, wobei die korrekte Klassifikation der Läsion als maligne in 50–80% der Fälle gelingt.Die moderne MR-Technologie der MRT mit MRCP stellt die optimale bildgebende diagnostische Strategie zur Abklärung zentraler Gallengangskarzinome dar, ergänzt durch die invasive ERC und in Einzelfällen durch die PTC. Interventionelle Embolisationstechniken zur Leberregeneration erhöhen den Anteil primär kurativ reserzierbarer Patienten.

Diagnostik des abdominellen Gefäßsystems mit der Elektronenstrahlcomputertomographie (EBT)

ZusammenfassungFragestellung: Die vorliegende Studie untersucht die Wertigkeit der Elektronenstrahlcomputertomographie (EBT) bei der prä- und postinterventionellen Abklärung von Pathologien des arteriellen und portalvenösen Gefäßsystems. Methodik: Innerhalb eines Jahres wurden 40 Patienten mit transjugulärem portosystemischem Shunt (TIPS), 12 Patienten mit peripherer arterieller Verschlußkrankheit (pavk) und 8 Patienten mit infarenalen Bauchaortenaneurysmata nach interventioneller Therapie prospektiv im EBT untersucht. Im Anschluß an die Untersuchung wurden Zeit-Dichte-Kurven und 3D-Rekonstruktionen der zu beurteilenden Gefäßabschnitte angefertigt. Die Ergebnisse wurden mit Befunden der Dopplersonographie und/oder DSA korreliert. Ergebnisse: Bei 30/40 TIPS-Patienten stimmte die EBT mit der Dopplersonographie bzw. der DSA überein, bei 3 Patienten konnte eine dopplersonographisch nachgewiesene und interventionell bestätigte Minderperfusion des TIPS im EBT nicht diagnostiziert werden. Bei 9/12 Patienten mit angiographisch nachgewiesenen Gefäßstenosen (>75%) konnte eine Abflachung und ein verzögerter Anstieg der Zeit-Dichte-Kurven nachgewiesen werden. Die Quantifizierung der Stenose mit den Zeit-Dichte-Kurven zeigte jedoch nur eine eingeschränkte Korrelation mit der i.a.-DSA. Bei den Patienten mit endovaskulär implantierter Aortenprothese konnte in allen Fällen eine komplette Ausschaltung des Aortenaneurysmas nachgewiesen werden. Schlußfolgerung: Die Vorteile der FBT bestehen in der Möglichkeit, zusätzlich zur „konventionellen” kontrastverstärkten Schnittbilddiagnostik aufgrund der methodisch bedingten hohen zeitlichen Auflösung auch dynamische Aspekte zu erfassen. Mögliche klinische Indikationen im Bereich des abdominellen Gefäßsystems bestehen insbesondere in der postinterventionellen Untersuchung zur Überprüfung des Interventionserfolges.SummaryPurpose: To evaluate the potential of electron-beam computed tomography (EBT) in the pre- and postinterventional assessment of vascular abdominal pathologies. Material and methods: Forty patients with implanted transjugular portosystemic shunt (TIPS), 12 patients with peripheral arterial occlusive disease and 8 patients with infrarenal abdominal aortic aneurysm after endovascular implantation of bifurcation stents were prospectively examined with contrast-enhanced EBT during one year. The evaluation included analysis of time-density curves (TDC) and 3D reconstructions. Results were compared with Doppler sonography and/or DSA. Results: In 30 of 40 TIPS patients, identical results were found with EBT, Doppler sonography and/or DSA. Reduced perfusions of the TIPS, which were subsequently confirmed by DSA, could not be shown with EBT in 3 patients. Nine of 12 patients with peripheral arterial occlusive disease and angiographically proven stenosis (>75%) showed a reduced and delayed peak density of the time-density curves. The quantification of arterial stenosis, however, did not follow the angiographic values. In all patients with the implanted bifurcation stents, EBT could correctly exclude a leakage of the stent. Conclusion: EBT has certain avantages over conventional spiral CT in the evaluation of abdominal vascular pathologies due to the additional assessment of perfusion parameters. Clinical indications for the use of EBT are seen especially in the postinterventional follow-up of patients with implanted stents.