Diagnostic performance of dynamic MR defecography in assessment of dyssynergic defecation.

PURPOSE: To assess diagnostic performance of MR defecographic findings in diagnosis of dyssynergic defecation (DD). METHODS: This retrospective study included 46 patients with chronic constipation who met the Rome IV criteria for diagnosis of present or absent DD and underwent MRI between Jan 2015 and June 2020. Patients were divided into DD group (n = 24) and non-DD group (n = 22). Nine parameters were analyzed by two radiologists: anorectal angle (ARA) and M line at rest, defecation, and change between 2 phases; anal canal width; prominent puborectalis muscle; abnormal evacuation. Receiver operating characteristic (ROC) curves were plotted to extract the optimal cut-offs and area under the curve (AUC). Multivariate analysis was performed. RESULTS: Seven findings showed statistically significant difference between DD and non-DD groups. M line at defecation had highest odds ratio, followed by ARA change, ARA at defecation, M line change, prominent puborectalis muscle, abnormal evacuation and anal canal width, respectively. ARA change and prominent puborectalis muscle had highest specificity (95.5% and 100%, respectively). The optimal cut-offs of ARA at defecation, ARA change, M line at defecation, M line change and anal canal width were 122°, 1.5°, 3.25 cm, 1.9 cm and 8.5 mm, respectively. Multivariate logistic regression revealed two significant findings in differentiating between DD and non-DD, including M line at defecation (OR 23.31, 95% CI 3.10-175.32) and ARA at defecation (OR 13.63, 95% CI 1.94-95.53) with sensitivity, specificity, PPV, NPV and AUC of 79.2%, 95.5%, 95%, 80.8% and 0.87(95% CI 0.78-0.97), respectively. CONCLUSION: MR defecography has high diagnostic performance in diagnosis of DD. Although M line and ARA at defecation are two significant findings on multivariate analysis, ARA change less than 1.5 degrees and prominent puborectalis muscle have good specificity in DD diagnosis.

Investigating the role of DCE-MRI, over T2 and DWI, in accurate PI-RADS v2 assessment of clinically significant peripheral zone prostate lesions as defined at radical prostatectomy.

PURPOSE: PI-RADS v2 dictates that dynamic contrast-enhanced (DCE) imaging be used to further classify peripheral zone (PZ) cases that receive a diffusion-weighted imaging equivocal score of three (DWI3), a positive DCE resulting in an increase in overall assessment score to a four, indicative of clinically significant prostate cancer (csPCa). However, the accuracy of DCE in predicting csPCa in DWI3 PZ cases is unknown. This study sought to determine the frequency with which DCE changes the PI-RADS v2 DWI3 assessment category, and to determine the overall accuracy of DCE-MRI in equivocal PZ DWI3 lesions. MATERIALS AND METHODS: This is a retrospective study of patients with pathologically proven PCa who underwent prostate mpMRI at 3T and subsequent radical prostatectomy. PI-RADS v2 assessment categories were determined by a radiologist, aware of a diagnosis of PCa, but blinded to final pathology. csPCa was defined as a Gleason score ≥ 7 or extra prostatic extension at pathology review. Performance characteristics and diagnostic accuracy of DCE in assigning a csPCa assessment in PZ lesions were calculated. RESULTS: A total of 271 men with mean age of 59 ± 6 years mean PSA 6.7 ng/mL were included. csPCa was found in 212/271 (78.2%) cases at pathology, 209 of which were localized in the PZ. DCE was necessary to further classify (45/209) of patients who received a score of DWI3. DCE was positive in 29/45 cases, increasing the final PI-RADS v2 assessment category to a category 4, with 16/45 having a negative DCE. When compared with final pathology, DCE was correct in increasing the assessment category in 68.9% ± 7% (31/45) of DWI3 cases. CONCLUSION: DCE increases the accuracy of detection of csPCa in the majority of PZ lesions that receive an equivocal PI-RADS v2 assessment category using DWI.

ACR Appropriateness Criteria Assessment of Fetal Well-Being.

Although there is limited evidence that antepartum testing decreases the risk for fetal death in low-risk pregnancies, women with high-risk factors for stillbirth should undergo antenatal fetal surveillance. The strongest evidence supporting antepartum testing pertains to pregnancies complicated by intrauterine fetal growth restriction secondary to uteroplacental insufficiency. The main ultrasound-based modalities to determine fetal health are the biophysical profile, modified biophysical profile, and duplex Doppler velocimetry. In patients at risk for cardiovascular compromise, fetal echocardiography may also be indicated to ensure fetal well-being. Although no single antenatal test has been shown to be superior, all have high negative predictive values. Weekly or twice-weekly fetal testing has become the standard practice in high-risk pregnancies. The timing for the initiation of assessments of fetal well-being should be tailored on the basis of the risk for stillbirth and the likelihood of survival with intervention. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer-reviewed journals and the application of well-established methodologies (the RAND/UCLA Appropriateness Method and the Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Optimizing adjuvant treatment decisions for stage t2 rectal cancer based on mesorectal node size: a decision analysis.

RATIONALE AND OBJECTIVES: The aim of this study was to optimize treatment decisions for patients with suspected stage T2 rectal cancer on the basis of mesorectal lymph node size at magnetic resonance imaging. MATERIALS AND METHODS: A decision-analytic model was developed to predict outcomes for patients with stage T2 rectal cancer at magnetic resonance imaging. Node-positive patients were assumed to benefit from chemoradiation prior to surgery. Imperfect magnetic resonance imaging performance for primary cancer and mesorectal nodal staging was incorporated. Five triage strategies were considered for administering preoperative chemoradiation: treat all patients; treat for any mesorectal node >3, >5, and >7 mm in size; and treat no patients. If nodal metastases or unsuspected stage T3 disease went untreated preoperatively, postoperative chemoradiation was needed, resulting in poorer outcomes. For each strategy, rates of acute and long-term chemoradiation toxicity and of 5-year local recurrence were computed. Effects of input parameter uncertainty were evaluated in sensitivity analysis. RESULTS: The optimal strategy depended on the outcome prioritized. Acute and long-term chemoradiation toxicity rates were minimized by triaging only patients with nodes >7 mm to preoperative chemoradiation (18.9% and 10.8%, respectively). A treat-all strategy minimized the 5-year local recurrence rate (5.6%). A 7-mm nodal triage threshold increased the 5-year local recurrence rate to 8.0%; when no patients were treated preoperatively, the local recurrence rate was 10.1%. With improved primary tumor staging, all outcomes could be further optimized. CONCLUSIONS: Mesorectal nodal size thresholds for preoperative chemoradiation should depend on the outcome prioritized: higher size thresholds reduce chemoradiation toxicity but increase recurrence rates. Improvements in nodal staging will have greater impact if primary tumor staging can be improved.

Prospective evaluation of MR enterography as the primary imaging modality for pediatric Crohn disease assessment.

OBJECTIVE: The objectives of this study were prospective evaluation of MR enterographic accuracy for detecting Crohn disease imaging features in pediatric patients, compared with a CT reference standard, as well as determination of MR enterographic accuracy for detecting active bowel inflammation and fibrosis using a histologic reference standard. SUBJECTS AND METHODS: The study group for this blinded prospective study included 21 pediatric subjects with known Crohn disease scheduled for clinical CT and histologic bowel sampling for symptomatic exacerbation. All subjects and their parents gave informed consent to also undergo MR enterography. CT and MR enterography examinations were independently reviewed by two radiologists and were scored for Crohn disease features. All bowel histology specimens were reviewed by a single pathologist for the presence of active mucosal inflammation and mural fibrosis, followed by correlation of imaging and histologic findings. RESULTS: All 21 subjects underwent MR enterography and histologic sampling, 18 of whom also underwent CT. MR enterography had high sensitivity for detecting Crohn disease imaging features (e.g., bowel wall thickening, mesenteric inflammation, lymphadenopathy, fistula, and abscess) compared with CT, with individual sensitivity values ranging from 85.1% to 100%. Of a total of 53 abnormal bowel segments with correlation of MRI and histologic findings, MR enterography showed 86.7% accuracy (90.0% sensitivity and 82.6% specificity) for detecting active inflammation (p < 0.001). The accuracy of MR enterography for detecting mural fibrosis overall was 64.9%, compared with histology, but increased to 83.3% (p < 0.05) for detecting fibrosis without superimposed active inflammation. CONCLUSION: MR enterography can substitute for CT as the first-line imaging modality in pediatric patients with Crohn disease, on the basis of its ability to detect intestinal pathologic abnormalities in both small and large bowel as well as extraintestinal disease manifestations. Additionally, MR enterography provides an accurate noninvasive assessment of Crohn disease activity and mural fibrosis and can aid in formulating treatment strategies for symptomatic patients and assessing therapy response.

Renal mass biopsy to guide treatment decisions for small incidental renal tumors: a cost-effectiveness analysis.

PURPOSE: To evaluate the effectiveness, cost, and cost-effectiveness of using renal mass biopsy to guide treatment decisions for small incidentally detected renal tumors. MATERIALS AND METHODS: A decision-analytic Markov model was developed to estimate life expectancy and lifetime costs for patients with small (< or = 4-cm) renal tumors. Two strategies were compared: renal mass biopsy to triage patients to surgery or imaging surveillance and empiric nephron-sparing surgery. The model incorporated biopsy performance, the probability of track seeding with malignant cells, the prevalence and growth of benign and malignant tumors, treatment effectiveness and costs, and patient outcomes. An incremental cost-effectiveness analysis was performed to identify strategy preference under a willingness-to-pay threshold of $75,000 per quality-adjusted life-year (QALY). Effects of changes in key parameters on strategy preference were evaluated in sensitivity analysis. RESULTS: Under base-case assumptions, the biopsy strategy yielded a minimally greater quality-adjusted life expectancy (4 days) than did empiric surgery at a lower lifetime cost ($3466), dominating surgery from a cost-effectiveness perspective. Over the majority of parameter ranges tested in one-way sensitivity analysis, the biopsy strategy dominated surgery or was cost-effective relative to surgery based on a $75,000-per-QALY willingness-to-pay threshold. In two-way sensitivity analysis, surgery yielded greater life expectancy when the prevalence of malignancy and propensity for biopsy-negative cancers to metastasize were both higher than expected or when the sensitivity and specificity of biopsy were both lower than expected. CONCLUSION: The use of biopsy to guide treatment decisions for small incidentally detected renal tumors is cost-effective and can prevent unnecessary surgery in many cases.

Staging MR lymphangiography of the axilla for early breast cancer: cost-effectiveness analysis.

OBJECTIVE: The purpose of this study was to compare the cost-effectiveness of MR lymphangiography-based strategies with that of sentinel lymph node (SLN) biopsy alone in the axillary staging of early breast cancer. MATERIALS AND METHODS: A decision-analytic Markov Model was developed to estimate quality-adjusted life expectancy and lifetime costs among 61-year-old women with clinically node-negative early breast cancer. Three axillary staging strategies were compared: MR lymphangiography alone, combined MR lymphangiography-SLN biopsy, and SLN biopsy alone. The model incorporated treatment decisions, outcome, and costs consequent to axillary staging results. An incremental cost-effectiveness analysis was performed to compare strategies. The effect of changes in key parameters on results was addressed in sensitivity analysis. RESULTS: In the base-case analysis, combined MR lymphangiography-SLN biopsy was associated with the highest quality-adjusted life expectancy (13.970 years) and cost ($63,582), followed by SLN biopsy alone (13.958 years, $62,462) and MR lymphangiography alone (13.957 years, $61,605). MR lymphangiography-SLN biopsy and SLN biopsy both were associated with higher life expectancy and cost relative to those of MR lymphangiography. MR lymphangiography-SLN biopsy, however, was associated with greater overall life expectancy and greater added life expectancy per dollar than was SLN biopsy. SLN biopsy alone therefore was not considered cost-effective, but MR lymphangiography and MR lymphangiography-SLN biopsy remained competing choices. Preference of MR lymphangiography strategies was most dependent on the sensitivity of MR lymphangiography and SLN biopsy and on the quality-of-life consequences of SLN biopsy and axillary lymph node dissection, but otherwise was stable across most parameter ranges tested. CONCLUSION: From a cost-effectiveness perspective, MR lymphangiography strategies for axillary staging of early breast cancer are preferred over SLN biopsy alone. The sensitivity of MR lymphangiography is a critical determinant of the cost-effectiveness of MR lymphangiography strategies and merits further investigation in the care of patients with early breast cancer.

Assessment of treatment response and recurrence in esophageal carcinoma based on tumor length and standardized uptake value on positron emission tomography-computed tomography.

BACKGROUND: Previous studies demonstrated that a decrease of the standardized uptake value between pretreatment and posttreatment positron emission tomography (PET) scans can predict histopathologic treatment response in patients with esophageal cancer. METHODS: Forty-seven patients who underwent PET-computed tomography (CT) scans before (scan 1) and after (scan 2) neoadjuvant chemoradiotherapy and during the follow-up period after surgery (scan 3) were included in this study. It was evaluated whether decrease of metabolic tumor length between scan 1 and scan 2 can predict histopathologic response to treatment. Moreover, the value of PET-CT was compared with PET in the assessment of tumor recurrence based on a visual analysis of scan 3. Reference standards for treatment response and recurrence were histopathology results. RESULTS: The reduction of tumor length between before and after chemoradiotherapy scans (between scan 1 and scan 2) was a better predictor of histopathologic response and of time to recurrence than the decrease in standardized uptake value. The most accurate differentiation was achieved when using a cut-off value of 33% reduction of the initial tumor length. Using this threshold to define metabolic response, the sensitivity was 91% (19 of 21) and the specificity was 92% (24 of 26) for predicting histopathologic treatment response. Based on a visual analysis, PET-CT was more accurate than PET in the differentiation of tumor recurrence from posttreatment tissue changes. Integrated PET-CT achieved a sensitivity of 91% (48 of 53) and a specificity of 81% (30 of 37) in identifying sites of tumor recurrence, compared with 83% (44 of 53) and 65% (24 of 37) with PET. CONCLUSIONS: Decrease of tumor length was shown to be a better predictor of treatment response and disease-free survival than decrease of standardized uptake value. Furthermore, PET-CT is more accurate in the evaluation of recurrence than PET.

Percutaneous cholecystostomy catheter removal and incidence of clinically significant bile leaks: a clinical approach to catheter management.

OBJECTIVE: We sought to determine the incidence of bile leaks upon removal of small-bore percutaneous cholecystostomy catheters and to evaluate clinical and imaging guidelines to ensure safe catheter removal. MATERIALS AND METHODS: A retrospective evaluation of all gallbladder drainages performed over a 5-year period revealed 163 patients (range, 7-98 years) who underwent percutaneous cholecystostomy catheter placement. Medical records and imaging studies were reviewed to assess the events at catheter removal (e.g., inadvertent removal, controlled removal with cholangiography without tract imaging, or controlled removal with cholangiography with tract imaging) and the incidence of major and minor bile leaks. RESULTS: The events at catheter removal were assessed in 66 patients. Group 1 was 45 patients whose catheters were removed after a minimum of approximately 3 weeks with a cholangiogram that established cystic and common duct patency and no imaging of the tract. Catheters were not removed until the patient recovered from acute illnesses that contributed to acalculous cholecystitis. Group 2 was 11 patients managed similarly to group 1 except that tract imaging was performed at catheter removal. Group 3 was 10 patients whose tubes came out inadvertently without cholangiogram or tract imaging. Two major (group 2 and group 3) and two minor (group 2) bile leaks occurred. No bile leaks occurred in group 1 (p = 0.006). CONCLUSION: Major bile leaks occurred in 3% of patients, and minor leaks occurred with equal frequency. Tract imaging may not be necessary in patients with small-bore gallbladder catheters who have recovered from critical illness, show patent cystic and common ducts, and have had catheters for 3-6 weeks.