[Dispensing with sedation in pediatric MR imaging of the brain: what is feasible?]. / Verzicht auf Sedierungen bei pädiatrischen MRT-Untersuchungen des Kopfes: Was ist machbar?

PURPOSE: Feasibility study to evaluate whether a diagnostic pediatric MRI scan of the brain can be performed without sedation by using BLADE sequences with rotating blade-like k-space covering. MATERIALS AND METHODS: Between 01/09 and 12/10 all children with a planned MRI of the brain were included. After age-dependent preparation of the child the MRI was acquired with a parent closely attending. Pharmacological sedation was only applied when strong motion artifacts occurred. All MRI sequences were independently reviewed by 2 radiologists who ranked image quality on a scale of III (excellent image quality, no motion artefacts), II (motion artefacts but still diagnostic quality), and I (non-diagnostic image quality). RESULTS: 326 children (53 % male, mean age 7.2 ± 4.3 years) were evaluated of whom 247 (76 %) had to be sedated. All infants < 1 year and 84 % of 1-year-old patients, 90 % of 2-year-old, 59 % of 3-year-old, 9 % of 4-year-old children, and 2 % of patients older than 4 years had to be sedated. In total, 2461 MRI sequences (7.6 ± 1.2 per study) including 622 BLADE sequences (25 %) were acquired. Reviewer A rated 2077 sequences (84 %) as III, 318 (13 %) as II, and 66 (3 %) as I, whereas reviewer B rated 2119 sequences (86 %) as III, 308 (13 %) as II, and 34 (1 %) as I. Inter-observer agreement was good to excellent (normal/weighted kappa value for BLADE sequences: 0.88/0.56, for all sequences: 0.92/0.71). CONCLUSION: Age-adjusted preparation and implementation of a pediatric cranial MRI may reduce the need for sedation. BLADE sequences abate motion artefacts thus enabling acquisition of diagnostic images even in young children. In patients older than 3 years, performance of MRI scans without sedation should be considered.

[Analysis of image acquisition, post-processing and documentation in adolescents with spine injuries - comparison before and after referral to a university hospital]. / Bildgebung bei wirbelsäulenverletzten Kindern und jungen Erwachsenen - eine Analyse von Umfeld, Standards und Wiederholungsuntersuchungen bei Patientenverlegungen.

PURPOSE: Systematic evaluation of imaging situation and standards in acute spinal injuries of adolescents. MATERIALS AND METHODS: Retrospective analysis of imaging studies of transferred adolescents with spinal injuries and survey of transferring hospitals (TH) with respect to the availability of modalities and radiological expertise and post-processing and documentation of CT studies were performed. Repetitions of imaging studies and cumulative effective dose (CED) were noted. RESULTS: 33 of 43 patients (77 %) treated in our hospital (MA 17.2 years, 52 % male) and 25 of 32 TH (78 %) were evaluated. 24-hr availability of conventional radiography and CT was present in 96 % and 92 % of TH, whereas MRI was available in only 36 %. In 64 % of TH, imaging expertise was guaranteed by an on-staff radiologist. During off-hours radiological service was provided on an on-call basis in 56 % of TH. Neuroradiologic and pediatric radiology expertise was not available in 44 % and 60 % of TH, respectively. CT imaging including post-processing and documentation matched our standards in 36 % and 32 % of cases. The repetition rate of CT studies was 39 % (CED 116.08 mSv). CONCLUSION: With frequent CT repetitions, two-thirds of re-examined patients revealed a different clinical estimation of trauma severity and insufficient CT quality as possible causes for re-examination. A standardization of initial clinical evaluation and CT imaging could possibly reduce the need for repeat examinations.

[Prognostic pulmonary and thoracic findings in patients with unstable injuries of the thoracic spine]. / Prognostische pulmonale und thorakale Befunde bei Patienten mit instabilen Verletzungen der Brustwirbelsäule.

BACKGROUND: Instable fractures of the thoracic spine imply a substantial trauma to the chest. The aim of this study was to undertake a systematic analysis of the prognostic impact of CT findings of the chest wall, mediastinum, lungs, and pleural space on the mortality rate. METHOD: All multiple injury patients with instable fractures of the thoracic spine and initial CT scans treated in our clinic from April 2004 to May 2007 were eligible. The following variables were evaluated for their prognostic power: injury to the lungs (pneumothorax, effusion, lung contusions/lacerations, atelectasis), mediastinum (vessel dissection/rupture, bleeding, diaphragmatic rupture), chest wall (bruises, soft tissue emphysema, rib fractures), and need for pre-diagnostic tube thoracostomy. The significance level was set to P = 0.05. PATIENTS: Of a total of 33 patients (mean age: 43.5 ± 20.1 years [range 14 - 83 years]; 25-male [76 %]), seven patients (21 %) died with women being significantly more affected (P < 0.001). Mortality rate was not influenced by patient age. RESULTS: Non-survivors displayed significantly higher median lung contusion score values compared to survivors (4.0 [0 - 12] versus 1.0 [0 - 10]; P = 0.016). The following variables revealed a significant association with the mortality rate: chest wall bruises with soft tissue emphysema > 90 ° of the thoracic circumference (sensitivity [SE]: 43 %, specificity [SP]: 100 %, positive predictive value [PPV]: 100 %, negative predictive value [NPV]: 87 %, overall accuracy [OA]: 88 %; P = 0.006), rib fractures (SE: 71 %, SP: 81 %, PPW: 50 %, NPW: 91 %, OA: 79 %; P = 0.016), mediastinal haematoma (SE: 71 %, SP: 77 %, PPW: 45 %, NPW: 91 %, OA: 76 %; P = 0.027), and bilateral pneumothoraces (SE: 29 %, SP: 100 %, PPW: 100 %, NPW: 84 %, OA: 85 %; P = 0.040). CONCLUSION: Multiply injured patients with instable fractures of the thoracic spine display CT findings indicative of non-survival. Image acquisition and interpretation focusing solely on the spine should be avoided to ensure the detection of prognostic injury patterns to the lungs.

[Assessment of pedicle screws following dorsal instrumentation of the spine: a comparison of conventional radiographs with multidetector CT]. / Lagebeurteilung transpedikulA currencyrer Schrauben nach dorsaler Spondylodese mittels konventioneller RA paragraph signntgenaufnahmen: ein Vergleich zur Mehrzeilen-Computertomografie.

PURPOSE: To evaluate the performance of conventional radiographs (CR) for the assessment of pedicle screws in comparison with CT including MPR. MATERIALS AND METHODS: Comparison of CR and CT for the evaluation of screw length, extracorporal perforation (grade A: 0 - 2 mm, B: 3 - 4 mm, C: 5 - 6 mm, D: > 6 mm, relevant: grade C and D), screw contact/loosening, and subjective image quality (1: excellent to 4: non-diagnostic). The sensitivity (SE), specificity (SP), positive (PPV) and negative predictive value (NPV), and overall accuracy (OA) were calculated with 4x4 contingency tables. The subjective image quality was evaluated using the Wilcoxon test (p < 0.05). RESULTS: 411 screws were evaluated. The relevant medial perforation was diagnosed with CR/CT in 53(13 %)/ 11(3 %) screws, while the relevant lateral perforation was found in 3(1 %)/ 43(11 %) screws. Pedicle screw contact was diagnosed by CR/CT in 10(2 %)/ 18(4 %) cases and incorrect length was confirmed in 80(20 %)/ 90(22 %) screws. A diagnosis of loosening was established in 10(2 %) screws by CR and in 7(2 %) screws by MDCT. In summary, CR demonstrated SE, SP, PPV, NPV, and OA for the following variables: relevant medial perforation = 64 / 89 / 13 / 99 / 88 %, relevant lateral perforation = 4 / 99 / 67 / 90 / 90 %, screw contact = 11 / 98 / 20 / 96 / 94 %, incorrect screw length = 86 / 58 / 89 / 51 / 81 %, and screw loosening = 71 %/ 99 %/ 50 %/ 100 %/ 98 %. The subjective image quality of CR was significantly lower compared to CT (2.19 A + or - 0.84 and 1.11 A + or - 0.31; p < 0.001). CONCLUSION: CR evaluation of pedicle screws following dorsal instrumentation of the spine demonstrated an OA < or = 90 % for relevant medial and lateral perforation and for incorrect screw length compared to CT. Thus, reliable evaluation of pedicle screws based solely on CR does not seem feasible.

[Structure of the meeting of the german radiological society and scientific discourse pertaining to radiation dose and dose reduction: an analysis of 1998 - 2008]. / Die Struktur des Deutschen Röntgenkongresses und die wissenschaftliche Behandlung der Themen Strahlendosis und Dosisreduktion: eine Analyse der Jahre 1998 - 2008.

PURPOSE: Evaluation of the emphasis of themes pertaining to radiation dose and dose reduction at the Meeting of the German Radiological Society from 1998 - 2008 in comparison to international data. MATERIALS AND METHODS: Retrospective analysis of 9440 abstracts with documentation of study presentation character, type of imaging, and examined body region. Abstracts stating radiation dose or primarily dealing with radiation dose/dose reduction were documented. Results were compared with a Pubmed query. RESULTS: The percentage of purely scientific presentations sank in the observation period from 88 to 66 %. While contributions dealing with MRI sank from 48 to 34 %, those dealing with CT rose from 30 to 34 %. The percentage of abstracts dealing with radiation dose rose from 7 to 10 %, while that of work primarily pertaining to dose/dose reduction grew from 4 to 6 % and 2 to 4 %, respectively. Of all abstracts concerning CT, 15 % touched on radiation dose, while 9 % and 6 % primarily dealt with dose and dose reduction. The respective numbers for cardiac CT, whose relative share of all CT abstracts rose from 3 % in 1998 to 12 % in 2008, were 10 %, 7 %, and 5 %. An online query produced 137,791 publications on CT, and 2 % of these abstracts mentioned radiation dose and 0.5 % mentioned dose reduction. CONCLUSION: The number of presentations dealing with dose at the Meeting of the German Radiological Society has risen with time and is higher than the international number. On the other hand, > 90 % of all presentations and > 85 % of all CT abstracts do not mention radiation dose. In light of increasing public concern relating to radiation exposure, more intensive research of these themes is warranted.

[Vertebral fractures in patients with ankylosing spondylitis: a retrospective analysis of 66 patients]. / Wirbelfrakturen bei patienten mit spondylitis ankylosans: eine retrospektive analyse von 66 patienten.

PURPOSE: Retrospective analysis of vertebral fractures in patients with ankylosing spondylitis (AS) for the evaluation of associations with mortality, concurrent neurological deficits, and other complications. MATERIALS AND METHODS: Image analysis (conventional radiographs, CT, MRI) was applied to all patients with AS admitted between 1997 and 2007 due to vertebral fractures to determine fracture location and classification. Patient characteristics, trauma mechanism, neurological symptoms, and other complications were documented. RESULTS: 66 patients (54 male, age 64 +/- 11 years) were enrolled in the study. 74 % of patients suffered from minor trauma. 51 % and 56 % had cervicothoracic and thoracolumbar fractures, respectively, while 8 % had multi-level fractures. 63 % of patients suffered combined vertebrodiscal fractures. 70 % revealed neurological symptoms, significantly correlating with spinal stenosis (p = 0.024; Odds ratio 4.265) and hyperlordosis (p = 0.014; OR 4.806). 68 % developed complications with non-combined fractures (p = .042; OR 4.954) and paravertebral hematomas (p = .009; OR 16.969) representing independent risk factors. The female gender (p = 0.005; OR 15.617) and conservative therapy (p = 0.040; OR.094) exerted significant influence on the mortality rate. CONCLUSION: Vertebral fractures frequently occur in patients with AS after minor trauma and often lead to neurological symptoms, which in turn are associated with spinal stenosis and hyperlordosis. Paravertebral hematomas and non-combined fractures are accompanied by higher incidences of other complications. The female gender entails a higher mortality rate.

[Awareness of radiation exposure of thoracic CT scans and conventional radiographs: what do non-radiologists know?]. / Einschätzung der Strahlenbelastung radiologischer Thorax-Verfahren: Was ist Nichtradiologen bekannt?

PURPOSE: Assessment of the knowledge of non-radiological physicians concerning radiation exposure during radiological procedures on the thorax. MATERIAL AND METHODS: 124 non-radiological physicians from the departments of surgery, internal medicine, anesthesiology, and neurology at a university hospital were questioned during a four-week period using a standardized questionnaire as to the effective dose (ED) of different radiological procedures on the thorax. The interviewees were asked to estimate the ED of chest X-rays and CT examinations and to compare these with the ED of other radiological methods. Length of professional experience, field of clinical training, and hierarchical position were also documented. The T-test and chi-square test were used for statistical analysis. RESULTS: 119/124 (96.0 %) physicians with an average work experience of 8.2 years (0.3-32 years) were willing to participate. 47/119 (39.5 %) correctly estimated the ED of conventional chest X-ray (0.01-0.1 mSv), and 40/119 (33.6 %) correctly gauged the ED of adult chest CT (1-10 mSv). The ED of cardiac CT and pediatric chest CT without dose reduction (10-100 mSv) were correctly judged by 31/119 (26.1 %) and 32/119 (26.9 %), respectively. The correct ratio of the ED of chest X-ray to that of chest CT (factor 100-1000) was given by 28/119 (23.5 %), while 86/119 (72.3 %) underestimated the ratio. 50/119 (42.0 %) and 35/119 (29.4 %) correctly stated that the ED of pediatric chest CT without dose reduction and that of cardiac CT are greater than that of adult chest CT. 24/119 (20.2 %) and 10/119 (8.4 %) thought that the ED of low-dose chest CT is smaller than that of chest X-ray or chest MRI, respectively. The length of professional experience, field of clinical training, and hierarchical position of the participants did not have a significant influence on the test results. CONCLUSION: Correct estimation of the ED of radiological chest examinations, especially that of CT examinations with a high ED, poses substantial difficulties for non-radiologists regardless of the length of professional experience and field of clinical training. In light of the increase in ordered radiological exams, targeted adaptation of medical school teaching content and promotion of pertinent continuing radiological education seem pressing.

[Mediastinal metastasis of a tubal choriocarcinoma following ectopic pregnancy as a rare cause of thoracic pain]. / Mediastinale Metastase eines tubaren Chorionkarzinoms nach ektoper Schwangerschaft als seltene Ursache thorakaler Schmerzen.

We report on a 26-year old female patient with thoracic pain and dyspnea, in whom a large tumorous mass in the anterior mediastinum with a pleural effusion was diagnosed by computed tomography and magnetic resonance imaging. After rapid progression of tumor growth and detection of malignant cells within the pleural effusion operative intervention including resection of the tumor was performed. Histologic examination of the tumor revealed the typical morphology of a large mediastinal choriocarcinoma. The excessively high hCG-levels returned to normal values post-operatively. A thorough history making revealed an ectopic pregnancy which had made unilateral salpingectomy necessary. Although primary histologic examination of the tubarian tissue had shown no malignancy, a secondary look revealed a choriocarcinoma with identical histological features compared to the mediastinal tumor. Thus, final diagnosis of a mediastinal metastasis of a tubarian choriocarcinoma in ectopic pregnancy was made. We discuss this extremely rare disease and provide a short overview of the literature.

[Non-passable tumor-associated stenosis of trachea and stent-implantation -- an indication for Virtual CT-bronchoscopy]. / Stent-Implantationsplanung bei tumor-assoziierter, brochoskopisch nicht passierbarer Trachealstenose -- Eine Indikation für die virtuelle CT-Bronchoskopie.

We report about a male 50-year-old patient with known non-small cell lung cancer and tumor-associated stenosis of the right main bronchus already treated with Neodym-YAG-laser coagulation. Eight months later the patient was readmitted to hospital and revealed complete occlusion of the right main bronchus and subtotal stenosis of the distal trachea and the left main bronchus. Conventional tracheobronchoscopy failed to visualize the post-stenotic parts of the left main bronchus due to the length and degree of stenosis. Multidetector-CT-generated virtual tracheobronchoscopy was able to demonstrate complete intraluminal tumor extent thus making precise pre-interventional measurements for stent implantation possible. Furthermore, post-interventional re-evaluation by virtual tracheobronchoscopy confirmed correct position and patency of the stent located within the distal trachea and the left main bronchus. Our case report demonstrates a non-invasive and easy approach for evaluating the tracheobronchial system in a patient with tumor-associated airway stenosis including the possibility for viewing beyond post-stenotic segments.

[Prospective randomized trial of a modified standard multislice CT protocol for the evaluation of multiple trauma patients]. / Prospektive, randomisierte Evaluation eines modifizierten Mehrdetektor-CT-Protokolls in der Initialdiagnostik beim Polytrauma.

PURPOSE: To evaluate whether modification of a standard multislice CT (MSCT) protocol might improve the diagnostic work flow in patients with multiple trauma without relevant loss of image quality. MATERIALS AND METHODS: Between September 2002 and September 2003, 80 multiple trauma patients underwent 4-slice CT encompassing head, thorax, abdomen/pelvis and spine. All patients were randomly assigned to either protocol A or B: Protocol A included serial scanning of the head (collimation 1 mm, 350/380 mAs/120 kV) and spiral scans of thorax, abdomen/pelvis and spine (collimation 2.5 mm, 220 mAs/120 kV) with gantry angulation and arm elevation; protocol B included spiral scanning of all body regions (collimation 2.5 mm, 300/150 mAs/120 kV) without gantry angulation or arm elevation. Time intervals, radiation exposure and results of the initial and final analysis were documented. RESULTS: In the investigated 64 male and 16 female patients (mean age 41.7 years), 88.7 % of the 407 pathologic findings were correctly identified on the initial images. Protocol B revealed a significant decrease in scan time (6.4 vs. 16.8 min., p < 0.001), time in the CT examination room (22.9 vs. 32.8 min.; p < 0.001), time until initial (25.3 vs. 35.8 min.; p < 0.001) and final image analysis (93.7 vs. 112.9 min; p < 0.005). No significant difference was found for patient transport time and image reconstruction time. Protocol B has a significantly lower effective radiation dose compared to protocol A (10.2 vs. 12.7 mSv, p < 0.001). CONCLUSIONS: Applying a modified MSCT protocol without gantry angulation and arm elevation can significantly decrease radiation exposure and examination time in multiple trauma patients without relevant loss of diagnostic image information and, consequently, has the potential of improving the diagnostic process and prognosis in multiple trauma patients.

[Misdiagnosis of a Leiomyosarcoma of the inferior vena cava as a renal cell carcinoma]. / Fehldeutung eines Leiomyosarkoms der V. cava inferior als Nierenzellkarzinom.

Leiomyosarcoma of the vena cava inferior (VCI) is a rare mesenchymal malignant tumor of the retroperitoneum. About 200 cases have been described in the literature so far. Leiomyosarcomas may resemble other tumors including renal cell carcinoma, adrenal carcinoma, and hepatic adenoma. Thus, misinterpretation of a leiomyosarcoma of the VCI is a common problem. We present a 71-year-old female with a large subhepatic, retroperitoneal tumorous mass which was diagnosed to be a renal cell carcinoma by sonography and computed tomography. After application of magnetic resonance imaging and retrospective analysis of the CT scan, diagnosis could be revised. Laparotomy and en bloc resection of the tumor was performed; histopathological examination confirmed a leiomyosarcoma of the VCI. The postoperative course was unremarkable. Leiomyosarcoma of the VCI may resemble advanced stages of renal cell carcinoma. High-resolution imaging modalities (computed tomography, magnetic resonance imaging) are able to precisely evaluate the typical imaging characteristics of leiomyosarcomas, thus determining correct diagnosis in affected patients. This is essential for successful operative therapy.

Management of the persistent ductus arteriosus in infants of very low birth weight: early and long-term results.

The hemodynamically relevant persistent ductus arteriosus (PDA) impairs pulmonary and cardiac function. Frequently, PDA can be closed only via surgery. In this retrospective study, early and long-term results in very low birth weight newborns are evaluated. Eighty-seven of 634 very low weight newborns presented with PDA All patients (pts; age: +/-14 days; weight: +/-1064 g) were ventilator-dependent. Surgical closure (after 29+/-5 days) was indicated if echocardiography and prolonged ventilation (>20+/-2 days) evidenced a hemodynamically relevant PDA. Sixteen pts, in which indomethacin therapy failed preoperatively are included in the 36 surgically treated pts; no pt died intra- or early postoperatively (<3 day). Overall mortality 30 days after delivery was n=9. Early plus late mortality was n=19. Long-term follow-up (3-12 years) in 46 (68%) pts: 15 were solely physically, 11 were mentally and neurologically, and 4 were physically, mentally and neurologically retarded. From these 30 pts, 15 were severely (e.g. tetraspasm; severe cerebral paresis) and 15 were slightly (e.g. psychosomatic and language development prolongation) retarded. Sixteen pts exhibited no disability; no long-term complications owing to surgery. The relatively large number of neurological injuries was not owing to chromosomal syndromes or pre-existing abnormalities but can be explained by severe and frequent prematurity, hypoxia, and intracerebral bleeding. Indomethacin was successful only in a few patients. Early surgery (after frustran early indomethacin therapy) of a hemodynamically relevant PDA is recommended. In the long-term, severe disabilities develop.