Joern O. Balzer

Surgical versus endovascular treatment of acute thoracic aortic rupture: a single-center experience

BACKGROUND Surgical management of acute thoracic aortic ruptures is controversial, especially in patients with preexisting comorbidities; associated mortality and paraplegia rates remain high. It was our objective to evaluate whether treating these patients acutely with endovascular stent grafts would improve their outcome. METHODS From November 1999 to February 2002 a total of 54 patients, age 28 to 83 years, were admitted to our institution with an acute rupture of the thoracic aorta (24 ruptured aneurysms, 14 perforated type B dissections, 16 traumatic ruptures). Twenty-eight patients were managed surgically using cardiopulmonary bypass (group 1), and 26 patients were treated acutely with an endovascular stent graft (group 2). The resuscitation protocol and interval from onset of symptoms to treatment was comparable in both groups. Medical records were reviewed for prehospitalization and emergency department data, operative findings, and outcomes. RESULTS There were 5 of 28 deaths (17.8%) in the surgical group and 1 of 26 deaths (3.8%) in the endovascular group. In the surgical group 1 of 28 patients (3.6%) exhibited paraplegia; there were no cases of paraplegia in the endovascular group. There were 4 of 28 cases (14.3%) of renal failure in group 1 and 1 of 26 (3.8%) in group 2. In group 1, 8 patients (28.6%) required mechanical ventilation for more than 48 hours; there were 2 of 26 patients (7.7%) in group 2 with this ventilatory requirement. Three patients required a repeat thoracotomy for hemorrhage in the surgical group. There were two access failures in the endovascular group. CONCLUSIONS In the treatment of acute ruptures of the thoracic aorta, the immediate outcome of patients treated with endovascular stent grafts appears to be better than with management by conventional surgical repair.

Emergent endovascular stent grafting for perforated acute type B dissections and ruptured thoracic aortic aneurysms

BACKGROUND The purpose of our study was to demonstrate the effectiveness of endovascular stent grafts in the treatment of acutely ruptured thoracic aortic aneurysms and type B dissections as an alternative to the conventional surgical approach in an emergency setting. METHODS From January 2001 to October 2001, we deployed 11 emergent endovascular stent grafts into the thoracic aorta. We treated seven ruptured aortic aneurysms and four acutely perforated type B dissections. Aortic rupture was confirmed preoperatively by spiral computed tomography. In all cases, hemothorax was present. The average interval from onset of symptoms to treatment was 28.5 hours. We used nine Talent and two Excluder stent grafts. RESULTS Deployment of the stent grafts was successful in nine cases. There were two cases of access failure due to small caliber of iliac arteries, and 1 of these patients died shortly after the procedure was abandoned, At 12 months of follow-up, there were no cases of paraplegia, stent migration, or endoleaks. There was, however, one temporary renal failure, and 2 patients required mechanical ventilation for more than 48 hours. CONCLUSIONS Our experiences with emergency endovascular stent grafting show that the procedure is technically feasible, with less morbidity and mortality than conventional open surgery, in high-risk patients.

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.

Analysis of Disk Volume before and after CT-guided Intradiscal and Periganglionic Ozone-Oxygen Injection for the Treatment of Lumbar Disk Herniation

PURPOSE To quantify the change in volume in herniated lumbar disk after computed tomography (CT)-guided intradiscal and periganglionic ozone-oxygen injection and to assess the effects of patient age, sex, and initial disk volume on disk volume changes. MATERIALS AND METHODS A total of 283 patients with lumbar radiculopathy received a single intradiscal (3 mL) and periganglionic (7 mL) injection of an ozone-oxygen mixture (ratio, 3:97; ozone concentration, 30 μg/mL). Under CT guidance, intradiscal and periganglionic injection was performed through an extraspinal lateral approach with a 22-gauge spinal needle. All disk volume changes were evaluated on CT 6 months after the procedure in all patients. RESULTS Initial mean disk volume was 17.37 cm(3) ± 4.70 (standard deviation; range, 8.12-29.15 cm(3)). Disk volume reduction (mean, 7.70% ± 5.45; range, 0.29%-22.31%) was seen in 96.1% of treated disks (n = 272) at 6 months after treatment and was found to be statistically significant (P < .0001). In 3.9% of patients (n = 11), disk volume increased (mean, 0.59% ± 0.24; range, 0.11%-0.81%). Patient age correlated negatively with disk volume reduction (r = -0.505; P < .0001) at 6 months after treatment, whereas initial disk volume correlated positively with volume reduction (r = 0.225; P = .00014) after therapy. No correlation was noted between patient sex and disk volume reduction after treatment (P = .09). CONCLUSIONS Intradiscal administration of medical ozone is associated with a statistically significant volume reduction of the herniated lumbar disk. The volume-reduction effect of ozone correlates negatively with the patients age and positively with initial disk volume.

Novel, Portable, Cassette-Sized, and Wireless Flat-Panel Digital Radiography System: Initial Workflow Results Versus Computed Radiography

OBJECTIVE The purpose of this article is to compare workflow efficiency between a conventional computed radiography (CR) system and a novel, portable, cassette-sized, and wireless flat-panel digital radiography (DR) system. MATERIALS AND METHODS Observational time-motion analyses were performed at one site at which CR and the new portable DR system are used concurrently. The workflow steps of both systems were identified and categorized to facilitate comparison. The times required for examination preparation, patient positioning, exposure, postacquisition processing, and the examination as a whole were recorded by a neutral observer. Timing differences between the CR and portable DR systems were compared, and all data were analyzed using commercially available statistical software. Nine general radiographic examination types were selected, with approximately 50 patients per examination type. RESULTS A total of 941 examinations (CR, n = 474; portable DR, n = 467) were timed in this study. Total examination time differences between CR and portable DR system (mean, 26.44 seconds; median 26.99 seconds) were found to be statistically significant (p < 0.001), with DR proving faster than CR. The single largest contributor to the time difference between CR and portable DR was postacquisition processing (mean, 26.58 seconds; median, 25.91 seconds), which was a composite of multiple individual steps, including cassette transport (CR only, mean, 13.22 seconds; median, 12.74 seconds), cassette readout (mean, 10.15 seconds; median, 10.4 seconds), and postprocessing (mean, 3.21 seconds; median, 3.11 seconds). CONCLUSION Overall radiographer time was significantly shorter when performing examination-related tasks with the novel, portable DR system than when performing comparable tasks with the CR system, a difference that appears to result largely from technology configuration.

Bleeding hepatic pseudoaneurysm complicating percutaneous liver biopsy with interventional treatment options

Hepatic percutaneous biopsy is considered to be a safe technique with reported average mortality and morbidity rates of about 0.01–0.1% and 0.1%, respectively. The reported rate of major complications, including hemorrhage, bile leak, hemothorax and perforation of the abdominal viscera, is around 3.2%. Pseudoaneurysms of the hepatic arteries are uncommon complication of percutaneous liver biopsy. However, when they occur they have a high risk of bleeding. Therefore, early management is required. A 50-year-old female was referred to our hospital with a history of ultrasound-guided percutaneous liver biopsy for the investigation of hepatosplenomegaly with liver cirrhosis diagnosed by ultrasound. The biopsy was performed with a 0.9-mm needle biopsy with a single pass. The immediate post-biopsy course was uneventful, and the patient was discharged from the hospital the same day. Three days later, the patient was admitted via the emergency unit with a history of acute abdominal pain and vomiting. There was no history of hematemesis or melena. On examination, the patient presented with jaundice and abdominal tenderness, which was more pronounced in the epigastric region. The vital signs were stable. Ultrasound examination of the abdomen was performed on admission and showed a large 10×9-cm hematoma in the right hepatic lobe. Conservative management of the hematoma with observation was employed, and she was followed up by daily ultrasound, which did not show any progression of the hematoma. Ten days later, the patient presented with persistant abdominal pain. CT scan of the abdomen showed an increase in the size of the previously diagnosed hematoma with a high suspicion of pseudoaneurysm. The patient was referred to our hospital for further assessment and management. The patient had a tri-phasic CT scan of the abdomen, which showed hepatosplenomegaly with a large heterogeneous mass lesion of low attenuation measuring about 15×16 cm in its longest axial access involving the right hepatic lobe in keeping with the previously diagnosed hepatic hematoma (Fig. 1). The late venous phase image showed a persistant enhancing area measuring around 2.5×1.5 cm within the above-described hematoma in keeping with the diagnosis of pseudoaneurysm (Figs. 2, 3). The patient underwent transarterial angiography with selective and super-selective catheter placement in the celiac artery and the left and right hepatic arteries employing a 4F catheter. The early arterial phase showed a pseudoaneurysm in a segmental branch of the right hepatic artery. Two coils of 4 mm in length and 3 mm in width were placed proximal to the aneurysm in the feeding artery. The post-embolization angiogram showed minimal blood flow within the pseudoaneurysm (Figs. 4, 5). The post-embolization course was uneventful, the bleeding was controlled, the patient was followed up by ultrasound and she was discharged home. Acute hemorrhage is the most common complication of liver biopsy, the majority of which are recognized before the patient is discharged from the hospital. There is an association of increased risk of hemorrhage and increased patient’s age undergoing liver biopsy, the number of passes and the use of atropine. It was found that there is an increased risk of nonfatal and fatal hemorrhage among patients biopsied for the investigation of malignancies when compared to patients biopsied for the investigations of diffuse liver disease. Pseudoaneurysms of the hepatic artery have been reported after percutaneReceived: 15 January 2004 Accepted: 3 February 2004 Published online: 6 March 2004

Multidetector-row CT: cardiosurgery indications

This article critically evaluates the role of multidetector-row CT before and after cardiosurgical procedures. In addition, technical aspects, such as scan protocols, optimal image reconstruction intervals, image reformation techniques, and data evaluation, are presented and briefly discussed.

Comparative study between mobile computed radiography and mobile flat-panel radiography for bedside chest radiography: impact of an antiscatter grid on the visibility of selected diagnostically relevant structures.

ObjectivesThe objective of this study was to evaluate the diagnostic performance of 2 different imaging systems in adult bedside chest radiography and the impact on the visibility of selected diagnostically relevant structures in the images acquired with these systems, with and without an antiscatter grid. Materials and MethodsWe acquired bedside chest radiographs of 103 intensive-care patients (36 women, 67 men; age range, 17–90 years; mean age, 66.4 years) using 4 acquisition techniques (computed radiography [CR] and digital radiography [DR], with and without grid). Image quality was evaluated independently by 4 radiologists using a 9-point visibility scale. Evaluated were lung parenchyma, soft tissues, thoracic spine, foreign bodies, and the overall image quality. Interobserver agreement and differences between the systems were tested using an interclass correlation (ICC) test. Mean scores were compared using the analysis of variance, followed by the post hoc pairwise testing (the Tukey test) in case of multiple group comparisons and by the Student t test in case of single group comparisons (P < 0.05, significant). ResultsThe image quality of the structures evaluated in the DR images with a grid was significantly higher than that obtained without a grid (P < 0.001) for all structures. The use of a grid in CR significantly improved the overall image quality, lung parenchyma, and soft tissue delineation (P < 0.001). Foreign body delineation, however, was significantly better in the CR images obtained without a grid (P < 0.001), whereas the 2 systems showed no significant difference regarding thoracic spine delineation (P = 0.554). The scores of the DR images were significantly higher than those of the CR images for all structures. The interobserver agreement was substantial for lung parenchyma (ICC, 0.77), soft tissue (ICC, 0.78), thoracic spine (ICC, 0.80), and the overall image quality (ICC, 0.78) and was almost perfect for foreign bodies (ICC, 0.81). ConclusionsThe use of an antiscatter grid significantly improved the image quality of bedside DR radiographs. A similar effect was seen with CR radiographs but only for lung parenchyma, soft tissue, and the overall image quality. Mobile DR outperformed CR in all structures.

Endovaskuläre Interventionen der thorakalen Aorta descendens

ZusammenfassungEndovaskuläre Eingriffe an der deszendierenden thorakalen Aorta haben sich in den letzten 10 Jahren als Alternative zur offenen chirurgischen Therapie etabliert. Zunächst war der Einsatz von endovaskulären Stentgrafts auf elektive Patienten mit einem Hochrisikoprofil für eine offene Operation beschränkt. Doch die Indikation wurde bald auch auf den notfallmäßigen Einsatz ausgeweitet.Bei elektiven Eingriffen an der deszendierenden thorakalen Aorta führte die endovaskuläre Therapie zu einem deutlichen Absinken der perioperativen Mortalität und Morbidität (Tabellen 1 und 2). Diese hervorragenden perioperativen Ergebnisse konnten auch in der Notfallsituation reproduziert werden und waren daher der offenen chirurgischen Therapie deutlich überlegen (Tabelle 3). Es bleibt die Frage der Langzeithaltbarkeit endovaskulärer Prothesen. Während Patienten nach offener chirurgischer Therapie kaum mit Spätkomplikationen rechnen müssen, wird in der Literatur von Stentgraftversagen im späten Verlauf berichtet (Abbildungen 1 und 2). Das Auftreten von Endoleaks (Abbildungen 3 und 4), Rupturen des Aneurysmasacks, Graftmigration und Materialverschleiß an den Stentgrafts wirft Fragen bezüglich der Langzeithaltbarkeit auf. Im Lichte dieser Spätkomplikationen bleibt die regelmäßige Nachsorge dieser Patienten notwendig, um letztendlich eine valide Aussage über Vorteile und Risiken dieser innovativen Technologie machen zu können.AbstractEndovascular interventions of the descending thoracic aorta have been established as an alternative to conventional open surgery. Initially, they were limited to elective patients with a high risk profile for open surgery, but soon their use was extended to emergencies as well.In the elective setting, endovascular interventions significantly lowered short-term morbidity and mortality. These excellent perioperative results were reproducible in the emergency setting, thereby leading to superior outcomes for patients treated by endovascular stent grafts when compared to the conventional open surgical approach. However, some questions regarding long-term durability of these devices remain unanswered. Stent-graft failures at midand long-term follow-up have been reported in the literature. The progressive nature of stent graft-related mid- and long-term complications stresses the need for continued surveillance of these patients.

Wertigkeit der hochauflösenden MRT für die Darstellung normaler und pathologischer Strukturen des Innenohres

ZusammenfassungZiel dieser Studie war die Überprüfung der Wertigkeit von hochauflösenden T2-gewichteten TSE-Sequenzen für die Darstellbarkeit normaler anatomischer und pathologischer Strukturen im Bereich des Innenohres und des inneren Gehörgangs. Insgesamt wurden 30 Probanden ohne klinische Symptomatik und 73 Patienten mit den klinischen Zeichen einer Innenohrerkrankung an einem 1,5-Tesla-MRT-Gerät mit der Kopfspule untersucht. Es kamen neben den konventionellen T2- und T1-gewichteten Sequenzen stark T2-gewichtete hochauflösende TSE-Sequenzen (TR/TE=4797/400) in transversaler und sagittaler Schichtorientierung zum Einsatz. Aus den transversalen TSE-Datensätzen wurden MIP-Rekonstruktionen angefertigt. Bei allen Probanden und 59 von 73 Patienten kamen die Kochlea, die Canales semicircularis lateralis, anterior und posterior sowie die Nervi facialis, cochlearis, vestibularis superior und inferior regelrecht zur Darstellung. Bei Patienten mit einem intrameatalen (n=3) oder intra-/extrameatalen (n=2) Akustikusneurinom gelang es, die exakte Lagebeziehung zwischen Tumor und nervalen Strukturen zu dokumentieren. Bei einem Patienten, der für eine Kochlea-Implantation vorgesehen war, zeigte sich eine Aplasie der Nervi cochlearis, vestibularis superior und inferior. Dieser Patient wies zudem eine Aplasie des Canalis semicircularis lateralis rechtsseitig auf. Bei einem Patienten mit einem Vestibularisneurinom zeigte sich eine Aplasie des Canalis semicircularis lateralis und posterior. Die hochauflösende MRT des Innenohres ermöglicht die exakte Darstellung normaler anatomischer und pathologischer Strukturen im Submillimeterbereich in einer Untersuchungszeit von 15 bis 20 min. Die MIP-Rekonstruktionen erlauben eine deutliche und präzise Darstellung der flüssigkeitsgefüllten Strukturen des Innenohres.SummaryOur aim was to evaluate the diagnostic potential of high resolution T2-weighted TSE sequences for the visualization of normal anatomical and pathological structures of the inner ear. Thirty volunteers without clinical findings and 73 patients with pathologic clinical findings were examined at a 1.5 Tesla scanner using a head coil. High resolution heavily T2-weighted sequences (TR/TE=4797/400) were used as well as conventional T2- and T1-weighted sequences in transverse and sagittal slice orientation. The high resolution T2-weighted images were used for MIP reconstructions. All volunteers and 59/73 patients demonstrated normal findings of the cochlea and the canales semicircularis posterior, anterior and lateralis and the facial, cochlear, superior and inferior vestibular nerve. Three patients demonstrated an intracanalicular and 2 an intra-/extracanalicular schwannoma of the vestibular nerve. A clear relationship between the nerves and the tumors could be demonstrated. One patient showed an aplasia of the superior and inferior vestibular nerve as well as the cochlea nerve and an aplasia of the lateral semicircular canal of the right side. One patient with a neurinoma of the vestibular nerve showed an aplasia of the lateral and posterior semicircular canal. High-resolution MRI of the inner ear enables the visualization of the submillimeter anatomical structures in an imaging time between 15 to 20 min. The MIP reconstructions provide a clear and precise presentation of the fluid content in the inner ear.