Correction to: National survey on dose data analysis in computed tomography.

The original version of this article, published on 28 May 2018, unfortunately contained a mistake.

Dynamic MRI of the pelvic floor: comparison of performance in supine vs left lateral body position.

OBJECTIVE:: To investigate the performance of MR-defecography (MRD) in lateral body position as an alternative to supine position. METHODS:: 22 consecutive patients (16 females; mean age 51 ± 19.4) with obstructed defecation and 20 healthy volunteers (11 females; mean age 33.4 ± 11.5) underwent MRD in a closed-configuration 3T-MRI in supine and lateral position. MRD included T2 weighted images at rest and during defecation after filling the rectum with 250 ml water-based gel. Measurements were performed in reference to the pubococcygeal line and grade of evacuation was assessed. Image quality (IQ) was rated on a 5-point-scale (5 = excellent). RESULTS:: In patients grades of middle and posterior compartment descent were similar in both body positions (p > 0.05). Grades of anterior compartment descent were significantly higher in lateral position (21/22 vs 17/22 patients with normal or small descent, p < 0.034). In volunteers grades of descent were similar for all compartments in supine and lateral position (p > 0.05). When attempting to defecate in supine position 6/22 (27%) patients showed no evacuation, while in lateral position only 3/22 (14%) were not able to evacuate. IQ in patients was equal at rest (4.4 ± 0.5 and 4.7 ± 0.6, p > 0.05) and slightly better in supine compared to the lateral position during defecation (4.5 ± 0.4 vs 3.9 ± 0.9, p < 0.017). IQ in volunteers was equal in supine and lateral position (p > 0.05). CONCLUSION:: In lateral position, more patients were able to evacuate with similar grades of pelvic floor descent compared to supine position. MRD in lateral position may be a valuable alternative for patients unable to defecate in supine position. ADVANCES IN KNOWLEDGE:: In lateral position, more patients were able to evacuate during MRD. MRD in lateral position may be an alternative for patients unable to defecate in supine position.

How to define pathologic pelvic floor descent in MR defecography during defecation?

OBJECTIVES: To assess the extents of pelvic floor descent both during the maximal straining phase and the defecation phase in healthy volunteers and in patients with pelvic floor disorders, studied with MR defecography (MRD), and to define specific threshold values for pelvic floor descent during the defecation phase. MATERIAL AND METHODS: Twenty-two patients (mean age 51 ± 19.4) with obstructed defecation and 20 healthy volunteers (mean age 33.4 ± 11.5) underwent 3.0T MRD in supine position using midsagittal T2-weighted images. Two radiologists performed measurements in reference to PCL-lines in straining and during defecation. In order to identify cutoff values of pelvic floor measurements for diagnosis of pathologic pelvic floor descent [anterior, middle, and posterior compartments (AC, MC, PC)], receiver-operating characteristic (ROC) curves were plotted. RESULTS: Pelvic floor descent of all three compartments was significantly larger during defecation than at straining in patients and healthy volunteers (p < 0.002). When grading pelvic floor descent in the straining phase, only two healthy volunteers showed moderate PC descent (10%), which is considered pathologic. However, when applying the grading system during defecation, PC descent was overestimated with 50% of the healthy volunteers (10 of 20) showing moderate PC descent. The AUC for PC measurements during defecation was 0.77 (p = 0.003) and suggests a cutoff value of 45 mm below the PCL to identify patients with pathologic PC descent. With the adapted cutoff, only 15% of healthy volunteers show pathologic PC descent during defecation. CONCLUSION: MRD measurements during straining and defecation can be used to differentiate patients with pelvic floor dysfunction from healthy volunteers. However, different cutoff values should be used during straining and during defecation to define normal or pathologic PC descent.

National survey on dose data analysis in computed tomography.

OBJECTIVES: A nationwide survey was performed assessing current practice of dose data analysis in computed tomography (CT). MATERIAL AND METHODS: All radiological departments in Switzerland were asked to participate in the on-line survey composed of 19 questions (16 multiple choice, 3 free text). It consisted of four sections: (1) general information on the department, (2) dose data analysis, (3) use of a dose management software (DMS) and (4) radiation protection activities. RESULTS: In total, 152 out of 241 Swiss radiological departments filled in the whole questionnaire (return rate, 63%). Seventy-nine per cent of the departments (n = 120/152) analyse dose data on a regular basis with considerable heterogeneity in the frequency (1-2 times per year, 45%, n = 54/120; every month, 35%, n = 42/120) and method of analysis. Manual analysis is carried out by 58% (n = 70/120) compared with 42% (n = 50/120) of departments using a DMS. Purchase of a DMS is planned by 43% (n = 30/70) of the departments with manual analysis. Real-time analysis of dose data is performed by 42% (n = 21/50) of the departments with a DMS; however, residents can access the DMS in clinical routine only in 20% (n = 10/50) of the departments. An interdisciplinary dose team, which among other things communicates dose data internally (63%, n = 76/120) and externally, is already implemented in 57% (n = 68/120) departments. CONCLUSION: Swiss radiological departments are committed to radiation safety. However, there is high heterogeneity among them regarding the frequency and method of dose data analysis as well as the use of DMS and radiation protection activities. KEY POINTS: • Swiss radiological departments are committed to and interest in radiation safety as proven by a 63% return rate of the survey. • Seventy-nine per cent of departments analyse dose data on a regular basis with differences in the frequency and method of analysis: 42% use a dose management software, while 58% currently perform manual dose data analysis. Of the latter, 43% plan to buy a dose management software. • Currently, only 25% of the departments add radiation exposure data to the final CT report.

Clinical-radiological scoring system for enhanced diagnosis of acute appendicitis.

INTRODUCTION: Acute appendicitis is the most common surgical condition in industrialized countries. However, diagnosis in borderline cases is often cumbersome and requires follow-up examinations, and/or a Computed Tomography examination. Therefore, our aim was to develop a combined clinical and sonographic score to enhance prediction of acute appendicitis. PATIENTS AND METHODS: The modified Alvarado score and various established sonographic criteria were investigated in 132 patients with suspected acute appendicitis. Two models were computed accounting for missing values. After analysis of sensitivity and specificity for the modified Alvarado score, logistic regression analysis was performed to identify significantly contributing sonographic features. RESULTS: The threshold of the logistic regression analysis of the two models resulted in the formula: modified Alvarado score+axial Appendix diameter [mm]. When the Appendix diameter is>8mm, 1 point/mm is added, while for a diameter<8mm, 1 point/mm is subtracted. The cut-off value is≥13 for acute appendicitis with a sensitivity 91.4% and a specificity of 100%, compared to a sensitivity of 90% and a specificity of 84.4% for the modified Alvarado score in our cohort. CONCLUSION: The established modified Alvarado score for diagnosis of acute Appendicitis can be improved by adding the axial diameter of the Appendix in a sonographic examination.

Implementation of a patient dose monitoring system in conventional digital X-ray imaging: initial experiences.

OBJECTIVES: The purpose was to report on the initial experience after implementation of a patient dose-monitoring system in conventional X-ray imaging. METHODS: A dose-monitoring system collected dose data relating to different radiographs (one projection) and studies (two or more projections). Images were acquired on digital X-ray systems equipped with flat-panel detectors. During period 1, examinations were performed in a routine fashion in 12,614 patients. After period 1, technical modifications were performed and radiographers underwent training in radiation protection. During period 2, examinations were performed in 14,514 patients, and the radiographers were advised to read dose data after each radiograph/study. Dose data were compared by means of kerma area product (KAP, gray × centimetre squared) and entrance surface air kerma (ESAK, milligray). RESULTS: During period 1, 13,955 radiographs and 8,466 studies were performed, and in period 2 16,090 radiographs and 10,389 studies. In period 2, KAP values for radiographs were an average of 25 % lower and for studies 7 % lower, and ESAK values for radiographs were 24 % lower and for studies 5 % lower. The reduction in KAP was significant in 8/13 radiographs and in 6/14 studies, and the reduction in ESAK was significant in 6/13 radiographs and 5/14 studies. CONCLUSIONS: Implementation of a patient dose-monitoring system in conventional X-ray imaging allows easy data collection, supports dose reduction efforts, and may increase radiographers' dose awareness. KEY POINTS: • A dose-monitoring system enables easy dose data collection in X-ray imaging. • The system facilitates dose reduction efforts and may increase radiographers' radiation awareness. • Mean kerma-area-product significantly declined in period 2 in 8/13 radiographs and 6/14 studies. • In ESAK a significant decline was evident in 6/13 radiographs and 5/14 studies.

Magnetic resonance imaging of pelvic floor dysfunction - joint recommendations of the ESUR and ESGAR Pelvic Floor Working Group.

OBJECTIVE: To develop recommendations that can be used as guidance for standardized approach regarding indications, patient preparation, sequences acquisition, interpretation and reporting of magnetic resonance imaging (MRI) for diagnosis and grading of pelvic floor dysfunction (PFD). METHODS: The technique included critical literature between 1993 and 2013 and expert consensus about MRI protocols by the pelvic floor-imaging working group of the European Society of Urogenital Radiology (ESUR) and the European Society of Gastrointestinal and Abdominal Radiology (ESGAR) from one Egyptian and seven European institutions. Data collection and analysis were achieved in 5 consecutive steps. Eighty-two items were scored to be eligible for further analysis and scaling. Agreement of at least 80 % was defined as consensus finding. RESULTS: Consensus was reached for 88 % of 82 items. Recommended reporting template should include two main sections for measurements and grading. The pubococcygeal line (PCL) is recommended as the reference line to measure pelvic organ prolapse. The recommended grading scheme is the "Rule of three" for Pelvic Organ Prolapse (POP), while a rectocele and ARJ descent each has its specific grading system. CONCLUSION: This literature review and expert consensus recommendations can be used as guidance for MR imaging and reporting of PFD. KEY POINTS: • These recommendations highlight the most important prerequisites to obtain a diagnostic PFD-MRI. • Static, dynamic and evacuation sequences should be generally performed for PFD evaluation. • The recommendations were constructed through consensus among 13 radiologists from 8 institutions.

Establishing Local Diagnostic Reference Levels in IR Procedures with Dose Management Software.

PURPOSE: To obtain local diagnostic reference levels (DRLs) in diagnostic and therapeutic IR procedures with dose management software to improve radiation protection. MATERIALS AND METHODS: Dose data of various vascular and nonvascular IR procedures performed within 18 months were collected and analyzed with dose management software. To account for different levels of complexity, procedures were subdivided into simple, standard, and difficult procedures as graded by interventional radiologists. Based on these analyses, local DRLs (given as kerma-area product [KAP]) were proposed. Comparison with dose data of others was conducted, and Spearman correlation coefficients were calculated to evaluate relationships between dose metrics. RESULTS: Analysis included 1,403 IR procedures (simple/standard/difficult, n = 346/702/355). Within the same procedure, KAP tended to increase with level of complexity. Overall, very strong correlation between KAP (Gy ∙ cm2) and cumulative air kerma (KA,R; Gy) was observed, and moderate to strong correlation between KAP and time and KA,R and time was observed. For simple procedures, strong correlation was seen between KAP and time and KA,R and time; for standard and difficult procedures, only moderate correlation was seen. Correlation between KAP and time and KA,R and time was strong in nonvascular procedures but only moderate in vascular procedures. CONCLUSIONS: Dose management software can be used to derive local DRLs for various IR procedures, taking into consideration different levels of complexity. Proposed local DRLs can contribute to obtaining detailed national DRLs as part of efforts to improve patients' radiation protection further.

Multilocular Hepatic Abscess Formation and Sepsis due to Yersinia enterocolitica in a Patient with Hereditary Hemochromatosis and Type 2 Diabetes Mellitus.

Infection with Yersinia enterocolitica (YE) typically presents with mild gastroenteritis without systemic infection. However, systemic YE infection has been described in states of iron overload. We present the case of a patient with sepsis with hepatic abscesses due to YE infection. Workup revealed a past diagnosis of diabetes mellitus and hemochromatosis which had been untreated for the previous 5 years due to patient refusal. This case highlights risk factors for systemic infection with YE. A high degree of suspicion for YE infection is warranted in patients with iron overload, diabetes mellitus, or immunosuppression.

Does Real-Time Monitoring of Patient Dose With Dose Management Software Increase CT Technologists' Radiation Awareness?

OBJECTIVE: Dose management software can be used to increase patient safety. The purpose of the current study was to evaluate whether real-time monitoring of patient dose in CT examinations increases CT technologists' dose awareness. MATERIALS AND METHODS: Dose data of two scanners (clinical routine CT scanner, mainly outpatients; emergency CT scanner, predominantly emergency department and ICU patients) were analyzed before (period 1) and after (period 2) dose management software was implemented in clinical routine and technologists were advised to check for dose notifications (dose values above reference levels) after each examination (i.e., real-time monitoring). To assess statistically significant differences between both the scanners and the study periods, we used chi-square tests. RESULTS: A total of 6413 examinations were performed (period 1 = 3214 examinations, period 2 = 3199 examinations). Dose notifications were mainly because of patient miscentering (period 1 = 45% of examinations, period 2 = 23%), overweight patients (period 1 = 35%, period 2 = 49%), and scanning repetition (period 1 = 10%, period 2 = 15%). Overall, the number of dose notifications significantly declined in period 2 (period 1, n = 210; period 2, n = 120; p < 0.001). Miscentering was more often seen on the clinical routine CT examinations (period 1 = 46%, period 2 = 23%) than on the emergency CT examinations (period 1 = 44%, period 2 = 22%) and occurred significantly less frequently on both scanners in period 2 (period 1: n = 94; period 2: n = 27; p < 0.001). The relative values of dose notifications due to overweight patients or scanning repetition were higher in period 2, but these differences did not reach statistical significance (p > 0.05). CONCLUSION: Real-time monitoring of patient dose with dose management software increases CT technologists' dose awareness and leads to a reduced number of dose notifications due to human error.

Combined Use of a Patient Dose Monitoring System and a Real-Time Occupational Dose Monitoring System for Fluoroscopically Guided Interventions.

PURPOSE: To determine the effect on patient radiation exposure of the combined use of a patient dose monitoring system and real-time occupational dose monitoring during fluoroscopically guided interventions (FGIs). MATERIALS AND METHODS: Patient radiation exposure, in terms of the kerma area product (KAP; Gy ∙ cm(2)), was measured in period 1 with a patient dose monitoring system, and a real-time occupational dose monitoring system was additionally applied in period 2. Mean/median KAP in 19 different types of FGIs was analyzed in both periods for two experienced interventional radiologists combined as well as individually. Patient dose and occupational dose were correlated, applying Pearson and Spearman correlation coefficients. RESULTS: Although FGIs were similar in numbers and types over both periods, a substantial decrease was found for period 2 in total mean ± SD/median KAP for both operators together (period 1, 47 Gy ∙ cm(2) ± 67/41 Gy ∙ cm(2); period 2, 37 Gy ∙ cm(2) ± 69/34 Gy ∙ cm(2)) as well as for each individual operator (for all, P < .05). Overall, KAP declined considerably in 15 of 19 types of FGIs in period 2. Mean accumulated dose per intervention was 4.6 µSv, and mean dose rate was 0.24 mSv/h. There was a strong positive correlation between patient and occupational dose (r = 0.88). CONCLUSIONS: Combined use of a patient dose monitoring system and a real-time occupational dose monitoring system in FGIs significantly lessens patient and operator doses.

Improving Patient Safety: Implementing Dose Monitoring Software in Fluoroscopically Guided Interventions.

PURPOSE: To assess whether dose monitoring software can be successfully implemented in fluoroscopically guided interventions and to provide dose data based on levels of complexity. MATERIALS AND METHODS: After launching the software (DoseWatch; GE Healthcare Systems, Buc, France), data were collected for 6 months and analyzed by means of kerma-area product (KAP; Gy/cm(2)), cumulative air kerma (KA,R; Gy), and fluoroscopic time (minutes). Data analysis was executed by level of complexity as graded by the operators. Complexity grading was based on factors such as tortuosity and calcification of vessel, variant anatomy, and patient cooperation. RESULTS: The software successfully transferred dose data of 357 fluoroscopically guided procedures. KAP was 0.238-400 Gy/cm(2) with mean, median, and 75th percentile values of 46.0 Gy/cm(2), 163.2 Gy/cm(2), and 541.1 Gy/cm(2) (KA,R, 0.013-4.1 Gy; mean, median, 75th percentile, 0.48 Gy, 0.97 Gy, 3.98 Gy). Highest dose values were seen in transarterial chemoembolization (KAP mean, median, 75th percentile, 229.5 Gy/cm(2), 216.4 Gy/cm(2), 299.9 Gy/cm(2); KA,R mean, median, 75th percentile, 1.9 Gy, 1.2 Gy, 1.7 Gy). Analysis revealed that the level of complexity strongly correlated with KAP (r = 0.88; P < .001) whereas there was no direct correlation of KAP and fluoroscopy time. During the same intervention, KA,R and fluoroscopy time increased with level of complexity, but the correlation was not statistically significant. CONCLUSIONS: Implementation of dose monitoring software in fluoroscopically guided interventions can be successfully accomplished, and it facilitates data comparison.

Assessment of Obstructive Defecation by High-Resolution Anorectal Manometry Compared With Magnetic Resonance Defecography.

BACKGROUND & AIMS: Patients with obstructive defecation have abnormalities of anorectal function and/or structure. Conventional anorectal manometry (ARM) can identify abnormal function and behavior (dyssynergia); however, agreement between manometry and defecography is only fair. High-resolution (HR)-ARM may improve diagnostic agreement by differentiating pressure effects caused by dyssynergia and obstruction. We compared HR-ARM findings with magnetic resonance (MR) defecography in the clinical assessment of patients with symptoms of obstructive defecation defined by Rome III criteria. METHODS: HR-ARM (Manoscan AR 360; Given Imaging, Yoqeam, Israel) assessed anal sphincter function and pressure during simulated defecation. Abnormal manometric findings were classified according to the Rao system and compared with MR defecography as the reference standard. RESULTS: A total of 188 consecutive patients (155 women; age, 19-93 y) with obstructive defecation underwent a full investigation. Compared with patients with dyssynergia on MR imaging (n = 66), patients with structural pathology (n = 87) had lower resting (P < .003) and squeeze pressures (P < .011), but a higher rectoanal pressure gradient (P < .0001) on HR-ARM. High intrarectal pressure with a steep, positive pressure gradient consistent with outlet obstruction on HR-ARM was present in 24 patients with intra-anal intussusception on MR imaging. This pattern was not observed in other patients. Interobserver agreement was substantial for HR-ARM diagnoses (κ = 0.67; 95% confidence interval, 0.559-0.779). Diagnostic accuracy for dyssynergia was 82% compared with MR imaging (sensitivity, 77% [51 of 66]; specificity, 85% [104 of 122]). CONCLUSIONS: The diagnostic agreement between anorectal HR-ARM and MR defecography is high and pressure measurements accurately identify recto-anal dyssynergia and intra-anal outlet obstruction by structural pathology as causes of obstructive defecation.

Abdominal aortic calcification and its distribution in normal-sized and aneurysmatic abdominal aortas.

BACKGROUND: Multi-detector computed tomography (MDCT) is more and more used for evaluation and quantification of coronary artery calcification, but correlation between the degree of calcification and occurrence of clinical events is also known for other vascular beds such as the aorta. PURPOSE: To assess possible differences in amount and pattern of calcification in aneurysmatic and non-aneurysmatic abdominal aortas. PATIENTS AND METHODS: Thirty-four subjects displayed infrarenal abdominal aneurysm (AAA) and were compared to 33 patients with normal-sized aortas using MDCT. Quantitative and qualitative analysis was performed by two radiologists. Calcium scores were assessed for the whole abdominal aorta as well as separately for the supra- and infrarenal segments. Moreover, plaque patterns were evaluated and classified according to their thickness and size. Furthermore, calcium scores were correlated with a number of cardiovascular risk factors. RESULTS: Total calcium scores were comparable in patients with and without AAA (1,213 ± 1,351 and 1,211 ± 1,535, respectively), but significant differences were found regarding plaque density that was considerably higher both in the supra- and infrarenal segments in the non-aneurysmatic group (AAA: suprarenal, 0.01, infrarenal, 0.07; non-AAA: suprarenal, 0.06, infrarenal, 0.16). Plaque pattern were considerably different in the infrarenal segments in aneurysmatic aortas: they were thinner (1 and 2 mm) and smaller (< 100 mm2) than in normal-sized aortas (mainly > 3mm and > 100 mm2). Distribution of risk factors was similar in both groups with the highest mean calcium score being present in patients with 4 risk factors. Pearson's correlation coefficient indicating correlation between total calcium score and number of risk factors was almost the same in both groups: AAA, r = 0.67; non-AAA, r = 0.65. CONCLUSIONS: Compared to normal-sized aortas thinner and smaller plaques are present in AAA, which may be due to degenerative processes.

Accuracy of multidetector-row CT for restaging after neoadjuvant treatment in patients with oesophageal cancer.

OBJECTIVES: To assess the diagnostic accuracy of 64-multidetector CT (MDCT) for restaging of patients with oesophageal cancer undergoing neoadjuvant therapy. METHODS: Results of pathological staging were correlated with those from 64-MDCT before and after neoadjuvant treatment in 35 patients using the American Joint Committee on Cancer/TNM classification (7th edition). CT response was determined using the Response Evaluation Criteria in Solid Tumours (RECIST) method, modified for one-dimensional tumour diameter measurement. RESULTS: 64-MDCT predicted T stage correctly in 34 % (12/35), overstaged in 49 % (17/35) and understaged in 17 % (6/35). Sensitivity/specificity values were as follows: T0, 20 %/92 %; T1-T2, 31 %/59 %; T3, 60 %/64 %; T4, 100 %/4 %. Negative predictive values for T3/T4 were 80 %/100 %. MDCT accurately predicted complete histopathological response in 20 % (accuracy 74 %) and overstaged in 80 %. Tumour regression grade was predicted correctly in only 8 % (2/25) and underestimated in 68 % (17/25). Accurate N stage was noted in 69 % (24/35). CONCLUSION: Although MDCT tends to be able to exclude advanced tumour stages (T3, T4) with a higher likelihood, the diagnostic accuracy of high resolution MDCT for restaging oesophageal cancer and assessing the response to neoadjuvant therapy has not improved in comparison to older-generation CT. Therefore, the future assessment of oesophageal tumour response should focus on combined morphologic and metabolic imaging. KEY POINTS: • Multidetector CT (MDCT) has been beneficial for the evaluation of many tumours. • However diagnostic accuracy for restaging oesophageal cancer has not improved with MDCT. • MDCT tends to be able to exclude advanced tumour stages (T3/T4). • MDCT has a low accuracy for determining lymph node metastasis. • Oesophageal tumour response should be assessed by combined morphological and metabolic imaging.

Accuracy and confidence of Gd-EOB-DTPA enhanced MRI and diffusion-weighted imaging alone and in combination for the diagnosis of liver metastases.

PURPOSE: To evaluate the accuracy and confidence in diagnosing liver metastases using combined gadolinium-EOB-DTPA (Gd-EOB-DTPA) enhanced magnetic resonance imaging (MRI)/diffusion-weighted imaging (DWI) in comparison to Gd-EOB-DTPA enhanced MRI and DWI alone. MATERIALS AND METHODS: Forty-three patients (age, 58 ± 13 years) with 89 liver lesions (28 benign, 61 malignant) underwent liver MRI for suspected liver metastases. Three image sets (DWI, Gd-EOB-DTPA and combined Gd-EOB-DTPA/DWI) in combination with unenhanced T1- and T2-weighted images were reviewed by three readers. Detection rates of focal liver lesions were assessed and diagnostic accuracy was evaluated by calculating the areas under the receiver-operating-characteristics curve (AUC). Confidence in diagnosis was evaluated on a 3-point scale. Histopathology and imaging follow-up served as the standard of reference. RESULTS: Detection of liver lesions and confidence in final diagnosis for all readers were significantly higher for the combined Gd-EOB-DTPA/DWI dataset than for DWI. The combination of DWI and Gd-EOB-DTPA rendered a significantly higher confidence in final diagnosis (2.44 vs. 2.50) than Gd-EOB-DTPA alone for one reader. For two readers, accuracy in diagnosis of liver metastases was significantly higher for Gd-EOB-DTPA/DWI (AUCs of 0.84 and 0.83) than for DWI datasets (AUCs of 0.73 and 0.72). Adding DWI to Gd-EOB-DTPA did not significantly increase diagnostic accuracy as compared to Gd-EOB-DTPA imaging alone. CONCLUSION: Addition of DWI sequences to Gd-EOB-DTPA enhanced MRI did not significantly increase diagnostic accuracy as compared to Gd-EOB-DTPA enhanced MRI alone in the diagnosis of liver metastases. However, the increase in diagnostic confidence might justify acquisition of DWI sequences in a dedicated MRI protocol.

Dynamic pelvic floor imaging: MRI techniques and imaging parameters.

Magnetic resonance imaging (MRI) is an excellent tool to understand the complex anatomy of the pelvic floor and to assess pelvic floor disorders. MRI enables static and dynamic imaging of the pelvic floor. Using static T2-weighted sequences the morphology of the pelvic floor can be visualized in great detail. A rapid half-Fourier T2-weighted, balanced steady state free precession, or gradient-recalled echo sequence are used to obtain sagittal images while the patient is at rest, during pelvic squeeze, during pelvic strain and to document the evacuation process. On these images the radiologist identifies the pubococcygeal line (PCL) (which represents the level of the pelvic floor). In normal findings, the base of the anterior and the middle compartment are above the PCL at rest, and the pelvic floor elevates during contraction. During straining the pelvic floor muscles should relax and the pelvic floor descends normally less than 3 cm below the PCL. Pelvic floor MRI based on the static and dynamic MRI sequences allows for the detection and characterization of a vast array of morphologic and functional pelvic floor disorders. In this review, we focus on technical aspects of static and dynamic pelvic floor MRI.

How accurate is unenhanced multidetector-row CT (MDCT) for localization of renal calculi?

PURPOSE: To investigate the correlation between unenhanced MDCT and intraoperative findings with regard to the exact anatomical location of renal calculi. DESIGN, SETTING, AND PARTICIPANTS: Fifty-nine patients who underwent unenhanced MDCT for suspected urinary stone disease, and who underwent subsequent flexible ureterorenoscopy (URS) as treatment of nephrolithiasis were included in this retrospective study. All MDCT data sets were independently reviewed by three observers with different degrees of experience in reading CT. Each observer was asked to indicate presence and exact anatomical location of any calcification within pyelocaliceal system, renal papilla or renal cortex. Results were compared to intraoperative findings which have been defined as standard of reference. Calculi not described at surgery, but present on MDCT data were counted as renal cortex calcifications. RESULTS: Overall 166 calculi in 59 kidneys have been detected on MDCT, 100 (60.2%) were located in the pyelocaliceal system and 66 (39.8%) in the renal parenchyma. Of the 100 pyelocaliceal calculi, 84 (84%) were correctly located on CT data sets by observer 1, 62 (62%) by observer 2, and 71 (71%) by observer 3. Sensitivity/specificity was 90-94% and 50-100% if only pyelocaliceal calculi measuring >4 mm in size were considered. For pyelocaliceal calculi≤4 mm in size diagnostic performance of MDCT was inferior. CONCLUSION: Compared to flexible URS, unenhanced MDCT is accurate for distinction between pyelocaliceal calculi and renal parenchyma calcifications if renal calculi are >4 mm in size. For smaller renal calculi, unenhanced MDCT is less accurate and distinction between a pyelocaliceal calculus and renal parenchyma calcification is difficult.

Professional satisfaction of radiologists in Switzerland.

QUESTIONS UNDER STUDY: To gain insight into the determinants of radiologists' professional satisfaction in Switzerland. METHODS: Data from 254 members of the Swiss Society of Radiology (76% men) obtained in a questionnaire survey were analysed by logistic regression analysis using socio-demographic, person- and workplace-related factors as independent variables (determinants) and satisfaction at work as the outcome variable. RESULTS: In terms of person-related factors within a complex logistical regression model, radiologists with low occupational self-efficacy and especially those with low mental wellbeing were at elevated risk for low professional satisfaction, with the latter determinant being the strongest predictor in the whole model. Regarding work-related determinants, low career satisfaction and high workload increased the risk of low job satisfaction while working in a university hospital was a protection factor against low job satisfaction with private practice being the reference. A total of 42% of the respondents enjoyed their job more, and 19% enjoyed it less compared to five years previously, while 39% experienced no change. CONCLUSION: Despite high workload, time and economic pressure, the majority of radiologists were professionally satisfied at a high level, which had even increased within the last five years. However, to keep this level of job satisfaction, career possibilities, especially in private practices, have to be improved. Furthermore, the radiologists' important contribution to the diagnostic and therapeutic process has to be recognised professionally as well as economically.

Molecular imaging of malignant tumor metabolism: whole-body image fusion of DWI/CT vs. PET/CT.

PURPOSE: To prospectively investigate the technical feasibility and performance of image fusion for whole-body diffusion-weighted imaging (wbDWI) and computed tomography (CT) to detect metastases using hybrid positron emission tomography/computed tomography (PET/CT) as reference standard. MATERIAL AND METHODS: Fifty-two patients (60 ± 14 years; 18 women) with different malignant tumor disease examined by PET/CT for clinical reasons consented to undergo additional wbDWI at 1.5 Tesla. WbDWI was performed using a diffusion-weighted single-shot echo-planar imaging during free breathing. Images at b = 0 s/mm(2) and b = 700 s/mm(2) were acquired and apparent diffusion coefficient (ADC) maps were generated. Image fusion of wbDWI and CT (from PET/CT scan) was performed yielding for wbDWI/CT fused image data. One radiologist rated the success of image fusion and diagnostic image quality. The presence or absence of metastases on wbDWI/CT fused images was evaluated together with the separate wbDWI and CT images by two different, independent radiologists blinded to results from PET/CT. Detection rate and positive predictive values for diagnosing metastases was calculated. PET/CT examinations were used as reference standard. RESULTS: PET/CT identified 305 malignant lesions in 39 of 52 (75%) patients. WbDWI/CT image fusion was technically successful and yielded diagnostic image quality in 73% and 92% of patients, respectively. Interobserver agreement for the evaluation of wbDWI/CT images was κ = 0.78. WbDWI/CT identified 270 metastases in 43 of 52 (83%) patients. Overall detection rate and positive predictive value of wbDWI/CT was 89% (95% CI, 0.85-0.92) and 94% (95% CI, 0.92-0.97), respectively. CONCLUSION: WbDWI/CT image fusion is technically feasible in a clinical setting and allows the diagnostic assessment of metastatic tumor disease detecting nine of 10 lesions as compared with PET/CT.