Lung Infarction Following Pulmonary Embolism: A Comparative Study on Clinical Conditions and CT Findings to Identify Predisposing Factors.

PURPOSE: The aim of this study was to identify factors predisposing to lung infarction in patients with pulmonary embolism (PE). MATERIALS AND METHODS: We performed a retrospective analysis on 154 patients with the final diagnosis of PE being examined between January 2009 and December 2012 by means of a Toshiba Aquilion 64 CT scanner. The severity of clinical symptoms was defined by means of a clinical index with 4 classes. The pulmonary clot load was quantified using a modified severity index of PE as proposed by Miller. We correlated several potential predictors of pulmonary infarction such as demographic data, pulmonary clot burden, distance of total vascular obstruction and pleura, the presence of cardiac congestion, signs of chronic bronchitis or emphysema with the occurrence of pulmonary infarction. RESULTS: Computed tomography revealed 78 areas of pulmonary infarction in 45/154 (29.2 %) patients. The presence of infarction was significantly higher in the right lung than in the left lung (p < 0.001). We found no correlation between pulmonary infarction and the presence of accompanying malignant diseases (r = -0.069), signs of chronic bronchitis (r = -0.109), cardiac congestion (r = -0.076), the quantified clot burden score (r = 0.176), and the severity of symptoms (r = -0.024). Only a very weak negative correlation between the presence of infarction and age (r = -0.199) was seen. However, we could demonstrate a moderate negative correlation between the distance of total vascular occlusion and the occurrence of infarction (r = -0.504). CONCLUSION: Neither cardiac congestion nor the degree of pulmonary vascular obstruction are main factors predisposing to pulmonary infarction in patients with PE. It seems that a peripheral total vascular obstruction more often results in infarction than even massive central clot burden.

Chest CT findings in EBUS-TBNA-proven anthracosis in enlarged mediastinal lymph nodes.

PURPOSE: We demonstrate the multislice computed tomography (MSCT) findings of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA)-proven hilar and mediastinal lymph node enlargement with signs of anthracosis. MATERIALS AND METHODS: 53 enlarged lymph nodes in 39 patients (28 male, 11 female) with EBUS-TBNA-confirmed anthracosis were analyzed retrospectively. RESULTS: The mean short axis diameter of the enlarged lymph nodes with signs of anthracosis was 13.7  mm. Lymph nodes most often showed an oval shape (84  %) and were well defined in 66  % of cases. Lymph node confluence was observed in 32  % of cases. Calcifications were documented in 24.5  % of cases. Contrast enhancement and fatty involution were seen seldom (3.8  %). Lymph node necrosis was not seen. CONCLUSION: Lymph node anthracosis may be found most often in enlarged, well defined lymph nodes with an oval shape, frequently associated with confluence and calcifications.

[Bowel perforation because of ingestion of a blister-wrapped tablet after post-interventional coronary perforation]. / Dünndarm-Perforation durch einen verschluckten Tabletten-Blister nach postinterventioneller Koronarperforation.

HISTORY AND ADMISSION FINDINGS: A 70-year-old woman was admitted to hospital with progressive chest pain. Coronary angiography demonstrated a significant stenosis of the left descending artery (LAD), which was treated by percutaneous coronary intervention (PCI) and stent implantation. During this intervention, a coronary perforation occurred which was remedied immediately. Five days after the intervention, the patient complained about severe atypical chest and abdominal pain with nausea and vomitting, but no fever. Physical examination revealed an acute abdomen of uncertain origin. INVESTIGATIONS: Laboratory tests revealed leukocytosis and elevated levels of C-reactive protein while cardiac enzymes were in normal range. The electrocardiogram showed no signs of acute myocardial ischemia. Abdominal x-ray was performed without any pathological findings. Further diagnostic tests, especially computed tomography of the abdomen, revealed an ingestion of a blister-wrapped tablet which had caused small bowel perforation and peritonitis. DIAGNOSIS, TREATMENT AND COURSE: An acute abdomen due to ingestion of a foreign body was diagnosed and an emergency laparotomy was performed immediately. The blister pack was removed by ileostomy. The further course was uneventful. CONCLUSION: The clinical presentation of abdominal pain is a frequent medical condition in hospital. Determining the cause requires precise assessment and examination and implicates a variety of differential diagnosis including non-cardiac and cardiac pain. Iatrogenic causes must be considered in differential diagnosis.

[Comparison of adrenal imaging and selective adrenal vein sampling in primary hyperaldosteronism]. / Vergleich von Bildgebung und seitengetrennter Nebennierenvenen-Blutentnahme zur Differentialdiagnose bei primärem Hyperaldosteronismus.

BACKGROUND AND OBJECTIVES: There is a high prevalence for primary hyperaldosteronism (PHA) in hypertensive patients. This retrospective study was performed to determine the role of adrenal scanning and adrenal vein sampling (AVS) in distinguishing unilateral autonomous adenoma from idiopathic bilateral hyperplasia (IHA). METHODS: 93 patients, admitted to the radiology department for AVS between 1996 and 2004, were enrolled. 44 had a diagnosis of PHA, 22 or whom had an adenoma and 22 had IHA. RESULTS: 17 of the 22 patients with adenoma and 15 with IHA had an aldosterone-renin ratio > 50. Adrenal CT or MR scanning was performed in 73 patients. Sensitivity and specificity were 56 % and 60 %, respectively, for CT and 57% and 67% for MR. In 87 patients AVS provided values for aldosterone (A) and cortisol (C) from the adrenal veins and vena cava inferior (VCI). Successful sampling (C-adrenal vein/C-VCI > 1.1) was achieved from 55 % of the right and from 92 % of the left adrenal veins. When AVS was successful on both sides, localizing adenoma was possible using A/C (site of adenoma) vs. A/C (contralateral) at a cut-off point > 3 (sensitivity 85 %, specifity 88 %). In patients with adenoma, aldosterone release was suppressed on the contralateral site (A/C-adrenal vein/A/C-VCI ratio = 0.8). CONCLUSION: AVS is a useful tool for localizing unilateral autonomous adenoma. However, selective sampling often fails on the right adrenal vein, which limits its significance. In this case the A/C-adrenal vein/A/C-VCI in combination with the posture test should be utilized. CT or MRI are of limited value.

[Improvements in detection of rectal cancer recurrence by multiplanar reconstruction]. / Verbesserte Rezidiverkennbarkeit mittels multiplanarer Rekonstruktion beim Rektumkarzinom in der Mehrzeilenspiralcomputertomographie.

PURPOSE: To evaluate the advantages of multiplanar reconstruction and different axial slice thickness in diagnostic of rectal cancer recurrence after operation and radiotherapy. METHOD: We included 83 patients after operation and radiotherapy of rectal cancer in this study. All patients got a minimum of three CT-examinations in their follow-up program. A total of 294 CT-scans were evaluated. Each examination was reviewed by two experienced radiologists in respect to recurrence. Each examination was presented in axial reconstruction with a slice sickness of 8, 5, and 1.25 mm and in multiplanar reconstruction. The sensitivity, specificity, positive predictive value and accuracy were calculated. RESULTS: Multiplanar reconstructions showed better results for the detection of recurrence than axial reconstruction. A reduced slice thickness did not lead to better results in axial reconstruction. Multiplanar reconstruction showed a sensitivity of 0.88, a specificity of 0.98, an accuracy of 0.96 and a positive predictive value of 0,94, for axial reconstruction we calculated: 0.82, 0.97, 0.94 and 0.88, respectively. Sensitivity and accuracy showed a significant increase after the first and second examination. CONCLUSION: Multiplanar reconstructions allow a significant better detection of rectal cancer recurrence when compared to axial reconstructions. Thinner axial slice thickness shows no diagnostic advantage.

[Stents in the femoral artery: aid or problem?]. / Stents in der Arteria femoralis: Hilfe oder Problem?

Percutaneous transluminal angioplasty (PTA) is a well-established technique in the treatment of symptomatic femoropopliteal artery stenoses and obstructions. It is a method of treatment with excellent initial technical and clinical results. However, the long-term results of PTA alone must be considered as unsatisfactory as recurrences are frequently observed. In the past, femoropopliteal stenting appeared to be a promising tool to prevent recurrence and to increase patency rates, but it did not produce better results than PTA alone. For this reason, alternative therapeutic strategies such as brachytherapy, drug-eluting pharmastents and gene therapy were developed. Several investigators are beginning to explore their potential use. This article reviews the present possibilities of PTA and stenting in the femoropopliteal region and considers potential future concepts. In this context, the current clinical literature is discussed.

CT fluoroscopy-guided abdominal interventions.

Computed tomographic fluoroscopy (CTF) is one of the most recent developments in helical computed tomography (CT), which is increasingly being used in interventional radiology. The method combines the advantages of CT with the real-time capabilities of ultrasonography. This article reviews the current clinical applications of CTF in the monitoring of abdominopelvic interventions with reference to published clinical studies.

[Observing the density increase curve after intravenous contrast medium administration using a bolus triggering system: a method for detection cardiovascular disorders?]. / Beobachtung der Dichteanstiegskurve nach intravenöser Kontrastmittelapplikation unter Verwendung eines Bolustriggerungsystems: eine Methode zur Detektion kardiovaskulärer Störungen?

PURPOSE: Recently bolus tracking systems were developed to improve the timing of intravenous contrast media application in helical computed tomography. We investigated the benefit of this new method as a parameter of the cardiac function. MATERIAL AND METHODS: Retrospective analysis of 64 patients which incidentally underwent bolus triggered contrast enhanced helical CT and invasive investigation of the heart within one week. All examinations were performed on the CT scanner Somatom Plus 4 Volume Zoom (Siemens Corp., Forchheim, Germany) using the C.A.R.E. Bolus software. This performs repetitive low-dose test scans (e.g. for the abdomen: 140 kV, 20 mA, Tl 0.5 s) and measures the Hounsfield attenuation (increase over the baseline) in a preselected region of interest. The displayed increase of vascular density over the time after peripheral contrast media injection (75 ml lopromid (300 mg/ml), 2 ml/s) was categorised to three types: (a) rapid increase, (b) deceleration before a 100 HE threshold was reached and (c) one or more peaks. The findings of the invasive investigation of the heart were correlated to the findings of the bolus-tracking measurements. RESULTS: The examinations were categorized as follows: 19 type A, 34 type B, 11 type C. We found a high significant correlation between the type of the Hounsfield attenuation and systolic pressure in the left ventricle. There was no correlation between the type of the Hounsfield attenuation and the diastolic pressure in the left ventricle, the pressures related to the right ventricle or the ejection fraction. The bolus-tacking system showed a sensitivity of 53, a specificity of 82, an accuracy of 70%, a positive predictive value of 70% and a negative predictive value of 70% in detection of left heart failure. CONCLUSION: The bolus tracking system C.A.R.E.-bolus often shows atypical Hounsfield attenuation in cases of cardiac failure but is not suitable as a screening method of the cardiopulmonary function.

Stereoscopic 3D CT vs standard 3D CT in the classification of acetabular fractures: an experimental study.

The accuracy of stereoscopic and standard three-dimensional (3D) CT in the classification of acetabular fractures was compared. A receiver operating characteristic (ROC) analysis was performed by two radiologists and two surgeons blinded to the presence of acetabular fractures in an animal model (a total of 62 porcine hips, 40 with artificial acetabular fractures). Classification of acetabular fractures was adopted from the literature. Interpretation was performed on a workstation using two specific volume rendering algorithms; unshaded and shaded bone. The ROC analysis did not demonstrate any benefit in stereoscopic 3D CT compared with standard 3D CT.

[Computerized tomography evaluation of local recurrence of operated and adjuvant radiation treated rectal carcinoma. Normal and pathological changes after operation and irradiation of rectal carcinoma in 956 CT examinations]. / Computertomographische Beurteilung von Lokalrezidiven beim operierten und nachbestrahlten Rektumkarzinom. Regelhafte und pathologische Veränderungen nach Operation und Bestrahlung des Rektumkarzinoms in 956 CT-Untersuchungen.

Colorectal carcinoma is one of the most common cancer in Germany. We want to evaluate the most reliable CT features indicating local recurrence of rectal cancer as early as possible. 232 patients suffering from rectal cancer being administered to our clinic from 1987-1998 were investigated. Criteria for inclusion: patients after surgery and radiotherapy of rectal cancer with a minimum follow-up of two years and at least 3 CT examinations. All CT examinations were analyzed standardized. The main target parameters for relapse were enlargement of a presacral mass, inhomogeneous appearance, asymmetric outlines, enlarged lymph nodes and infiltration of the surrounding structures. An unchanged appearance of the presacral space in more than three CT examinations after surgery correlated with freedom of recurrence.

["Phtisis atra"--a now seldom disease picture as a special disease course of silicosis]. / "Phtisis atra"--ein heute seltenes Krankheitsbild als besondere Verlaufsform der Silikose.

Progressive massive fibrosis (PMF) of the lung is caused by coalescence of fibrotic nodules. The center of the PMF often displays necrotic areas. If the necrosis gets in contact to the bronchial system cavitation may occur. We report on a 68 year old patient suffering from severe silicosis of the lung and metastatic spread of a histologically proven lung cancer into the brain. The patient who was administered to the hospital under the intention of cerebral radiotherapy showed a colliquative PMF in the right upper lobe with cavitation and expectoration of large amounts of black-stained sputum (melanoptysis).

Magnetic resonance imaging in the diagnosis of Fournier's gangrene.

Magnetic resonance imaging and ultrasound are the imaging modalities recommended in the early diagnosis of Fournier's gangrene. Because of the high mortality of this inflammatory disease early diagnosis is essential to initiate adequate surgical and medical treatment. In the clinical literature only a handful of cases, in which diagnosis of Fournier's gangrene is based on MRI findings, have been reported; therefore, we report another case which shows the ability of MRI especially to determine the point of origin and extension of disease.

Successful treatment of intimal hyperplasia in renal arteries by endovascular brachytherapy.

PURPOSE: The present study shows the possibility of preventing restenosis of renal arteries by endovascular brachytherapy. METHODS AND MATERIALS: We present a patient suffering from rapid restenosis of both renal arteries with decreasing renal function. Percutaneous transluminal angioplasty (PTA) and stent implantation were unable to stop hypertension and to stabilize renal function. Both renal arteries and the right pole artery were treated by endovascular brachytherapy in one session. RESULTS: Six months after intervention, intraarterial digital subtraction angiography (DSA) showed no evidence of recurrence, and the blood pressure remained normal without medical treatment. CONCLUSION: Endovascular brachytherapy can help to prevent restenosis in renal arteries. It is possible to treat both renal arteries and one pole artery in one session without any disadvantage.

First experiences in CT-guided percutaneous transhepatic biliary decompression by means of real-time CT fluoroscopy.

BACKGROUND: Computed tomographic fluoroscopy (CTF), also called real-time CT, is increasingly used in interventional radiology but has not yet been recommended to guide percutaneous transhepatic biliary decompression (PTBD). We report our early clinical experiences with CTF-guided PTBD. METHODS: Sixteen consecutive patients underwent PTBD under CTF guidance because of obstructive jaundice caused by malignant tumor (11 cases of carcinoma of the bile duct, four cases of pancreatic cancer, and one case of metastasis). CTF-guided PTBD was performed on a helical CT scanner and a surgical C arm. Main target parameters were the success and complication rates, the number of necessary punctures, the time needed for successful puncture of a suitable bile duct, and the patients' radiation exposure. RESULTS: CTF-guided punctures of the bile duct for PTBD were successful on the first trial in 10 cases; in six patients, two hits were necessary. The time needed to hit a suitable bile duct was 6-21 s (median = 13 s). Therefore, the radiation exposure (skin) was 27-94.5 mSv. The additional implantation and stenting of the bile duct by means of the surgical C arm was uneventful in 15 cases. In one case, only external drainage could be achieved. Complications did not occur. CONCLUSION: CTF enables good visualization of the most suitable duct for puncture. Therefore, subsequent recanalization seems to be easier than other methods.

A comparative study of CT fluoroscopy combined with fluoroscopy versus fluoroscopy alone for percutaneous transhepatic biliary drainage.

PURPOSE: We compared CT fluoroscopy (CTF) for the initial puncture of bile ducts with conventional fluoroscopic guidance in patients with malignant jaundice in whom percutaneous transhepatic biliary drainage (PTBD) was planned. METHODS: Forty consecutive patients were randomized to two study groups: group A underwent PTBD under CTF and fluoroscopic guidance, group B underwent PTBD under fluoroscopic guidance alone. CTF-guided PTBD was performed using a combination of a helical CT scanner of the latest generation and a mobile C-arm; conventional PTBD was performed under fluoroscopic guidance in the angiographic unit. End points of the study were the success (a puncture that enabled safe placement of a guidewire in a suitable bile duct) and the complication rate (hemobilia, bile fistula, biliary peritonitis), the number of punctures required, the time needed for successful puncture of a suitable bile duct, and the patient's radiation exposure. RESULTS: CTF-guided puncture of peripheral bile ducts suitable for PTBD was successful at the first attempt in 16 cases, under conventional fluoroscopic guidance, in only two cases. We found a significantly different number of punctures (1.2 in group A vs 2.9 in group B), a significantly shorter time for puncture in group A (mean 39 sec), but also a significantly higher skin exposure dosage in group A (mean 49.5 mSv surface dosage). There was no significant difference regarding the total procedure time. Only one complication occurred in group B (portobiliary fistula). CONCLUSION: CTF-guided initial puncture of bile ducts allowed a significantly reduced number of punctures and puncture times compared with puncture under conventional fluoroscopic guidance for placement of percutaneous transhepatic biliary drainage catheters.

[Virtual bronchoscopy in the child using multi-slice CT: initial clinical experiences]. / Virtuelle Bronchoskopie am Kind unter Verwendung der Mehrzeilen-Spiral-CT: erste klinische Erfahrungen.

PURPOSE: Virtual bronchoscopy of the pediatric patient has been reported to be more difficult because of artifacts due to breathing or motion. We demonstrate the benefit of the accelerated examination based on multislice spiral CT (MSCT) in the pediatric patient which has not been reported so far. MATERIAL AND METHODS: MSCT (tube voltage 120 kV, tube current 110 mA, 4 x 1 mm Slice thickness, 500 ms rotation time, Pitch 6) was performed on a CT scanner of the latest generation (Volume Zoom, Siemens Corp. Forchheim, Germany). In totally we examined 11 patients (median age 48 months, range 2-122 months) suspected of having tracheoesophageal fistula (n = 2), tracheobronchial narrowing (n = 8) due to intrinsic or extrinsic factors or injury of the bronchial system (n = 1). RESULTS: In all patients we obtained sufficient data for 3D reconstruction avoiding general anesthesia. 6/11 examinations were described to be without pathological finding. A definite diagnosis was obtained in 10 patients. Virtual bronchoscopy could avoid other invasive diagnostic examination in 8/11 patients (73%). CONCLUSION: Helical CT provides 3D-reconstruction and virtual bronchoscopy in the newborn as well as the infant. It avoids additional diagnostic bronchoscopy in a high percentage of all cases.

[Computed tomography and magnetic resonance tomography in tuberculous spondylitis. A review of the literature and the authors' own observations]. / Computertomographie und Magnetresonanztomographie bei tuberkulöser Spondylitis. Literaturübersicht und eigene Beobachtungen.

PURPOSE: The findings of tuberculous spondylitis in MRT have been described extensively. Nevertheless the diagnostic value of both methods in the diagnosis of this severe manifestation of the tuberculous disease was not yet defined definitely. MATERIALS: We performed a review of the recent literature and a retrospective analysis of the findings in ten patients with proven tuberculous spondylitis. Here we evaluated 10 CT and 6 MRT. RESULTS: Major findings in computed tomography (n = 10) were osseous sequestration (8/10), subperiosteal bone apposition (6/10), abscess of the surrounding tissue. (8/10) and calcification of the masses (3/10). In all cases which were examined by MRT (n = 6) marrow edema was seen. Affection of the soft tissue was described by means of MRT in 5/6 patients. All patients showed rim enhancement. CONCLUSIONS: MRT shows signs of infection (bone marrow edema) which is an early but rather unspecific finding. The commonness of osseous lesions in advanced tuberculous spondylitis suggests a benefit of computed tomography in the later stages. Both methods are complementary in the differential diagnosis of tuberculous and non-specific spondylitis.

Better visualization of transbronchial biopsy using CT fluoroscopy.

PURPOSE: Computed tomography fluoroscopy (CTF) provides the capability for continuous CT imaging and has been increasingly used in interventional procedures. Our objective was to assess the usefulness of CTF in the monitoring of transbronchial biopsy procedures. METHODS: We evaluated nine patients in whom yield of "conventional" transbronchial biopsies had failed. CTF was performed on a Somatom Plus 4 Power scanner (CARE Vision CT, Siemens, Forchheim, Germany) using 120 kV, 50 mA at a frame rate of eight images per second on a matrix of 256 x 256. Image reconstruction was based on a partial scan with an acquisition time of 0.5 sec. The maximal time without interruption was 79 sec; after stopping for a few seconds a new period of 79 sec was available. The number of biopsies, procedure times, applied dose, and histologic results were documented. RESULTS: With CTF-guided transbronchial biopsy, the yield of the biopsies was improved. In seven patients biopsy yielded bronchial cancer; in one patient histopathologic examination showed tuberculosis. Only in one patient did CTF-guided transbronchial biopsy fail. The mean number of biopsies was four in each patient. Mean fluoroscopy time was 165 +/- 92 sec (range 111-272 sec) and mean procedure time was 800 +/- 302 sec (range 480-1081 sec). The applied dose ranged between 500 and 1224 mSv; the mean applied dose was 743 +/- 414 mSv. There were no fatal complications. CONCLUSION: Computed tomography fluoroscopy appears to facilitate visualization of transbronchial biopsy procedures, with the drawback of increased radiation exposure. To compare the "conventional" method versus CTF a randomized prospective study is necessary.

[Duodeno-ileal fistula development due to retroperitoneal lymph node metastases of sigmoid carcinoma]. / Duodenoileale Fistelbildung durch retroperitoneale Lymphknotenmetastasen eines Sigmakarzinomas.

We report on a 75-year-old patient suffering from persistent diarrhea with consecutive weight loss of 50 kg over a nine month period. Three years ago the patient had been operated on a sigmoid cancer. Ultrasonography and CT-scan revealed retroperitoneal masses due to lymph node metastases. Enteroclysis demonstrated a fistula between the duodenum and the terminal ileum. Whereas duodenocolic fistulae due to malignancies are well known to the best of our knowledge a fistula between retroperitoneal parts of the duodenum and the intraperitoneal intestine have not descripted so far.