Introduction of a breast apparent diffusion coefficient category system (ADC-B) derived from a large multicenter MRI database.

OBJECTIVES: To develop an intuitive and generally applicable system for the reporting, assessment, and documentation of ADC to complement standard BI-RADS criteria. METHODS: This was a multicentric, retrospective analysis of 11 independently conducted institutional review board-approved studies from seven institutions performed between 2007 and 2019. Breast Apparent Diffusion coefficient (ADC-B) categories comprised ADC-B0 (ADC non-diagnostic), ADC-B1 (no enhancing lesion), and ADC-B2-5. The latter was defined by plotting ADC versus cumulative malignancy rates. Statistics comprised ANOVA with post hoc testing and ROC analysis. p values ≤ 0.05 were considered statistically significant. RESULTS: A total of 1625 patients (age: 55.9 years (± 13.8)) with 1736 pathologically verified breast lesions were included. The mean ADC (× 10-3 mm2/s) differed significantly between benign (1.45, SD .40) and malignant lesions (.95, SD .39), and between invasive (.92, SD .22) and in situ carcinomas (1.18, SD .30) (p < .001). The following ADC-B categories were identified: ADC-B0-ADC cannot be assessed; ADC-B1-no contrast-enhancing lesion; ADC-B2-ADC ≥ 1.9 (cumulative malignancy rate < 0.1%); ADC-B3-ADC 1.5 to < 1.9 (0.1-1.7%); ADC-B4-ADC 1.0 to < 1.5 (10-24.5%); and ADC-B5-ADC < 1.0 (> 24.5%). At the latter threshold, a positive predictive value of 95.8% (95% CI 0.94-0.97) for invasive versus non-invasive breast carcinomas was reached. CONCLUSIONS: The breast apparent diffusion coefficient system (ADC-B) provides a simple and widely applicable categorization scheme for assessment, documentation, and reporting of apparent diffusion coefficient values in contrast-enhancing breast lesions on MRI. CLINICAL RELEVANCE STATEMENT: The ADC-B system, based on diverse MRI examinations, is clinically relevant for stratifying breast cancer risk via apparent diffusion coefficient measurements, and complements BI-RADS for improved clinical decision-making and patient outcomes. KEY POINTS: • The breast apparent diffusion coefficient category system (ADC-B) is a simple tool for the assessment, documentation, and reporting of ADC values in contrast-enhancing breast lesions on MRI. • The categories comprise ADC-B0 for non-diagnostic examinations, ADC-B1 for examinations without an enhancing lesion, and ADC-B2-5 for enhancing lesions with an increasing malignancy rate. • The breast apparent diffusion coefficient category system may be used to complement BI-RADS in clinical decision-making.

A simple scoring system for breast MRI interpretation: does it compensate for reader experience?

PURPOSE: To investigate the impact of a scoring system (Tree) on inter-reader agreement and diagnostic performance in breast MRI reading. MATERIALS AND METHODS: This IRB-approved, single-centre study included 100 patients with 121 consecutive histopathologically verified lesions (52 malignant, 68 benign). Four breast radiologists with different levels of MRI experience and blinded to histopathology retrospectively evaluated all examinations. Readers independently applied two methods to classify breast lesions: BI-RADS and Tree. BI-RADS provides a reporting lexicon that is empirically translated into likelihoods of malignancy; Tree is a scoring system that results in a diagnostic category. Readings were compared by ROC analysis and kappa statistics. RESULTS: Inter-reader agreement was substantial to almost perfect (kappa: 0.643-0.896) for Tree and moderate (kappa: 0.455-0.657) for BI-RADS. Diagnostic performance using Tree (AUC: 0.889-0.943) was similar to BI-RADS (AUC: 0.872-0.953). Less experienced radiologists achieved AUC: improvements up to 4.7 % using Tree (P-values: 0.042-0.698); an expert's performance did not change (P = 0.526). The least experienced reader improved in specificity using Tree (16 %, P = 0.001). No further sensitivity and specificity differences were found (P > 0.1). CONCLUSION: The Tree scoring system improves inter-reader agreement and achieves a diagnostic performance similar to that of BI-RADS. Less experienced radiologists, in particular, benefit from Tree. KEY POINTS: • The Tree scoring system shows high diagnostic accuracy in mass and non-mass lesions. • The Tree scoring system reduces inter-reader variability related to reader experience. • The Tree scoring system improves diagnostic accuracy in non-expert readers.

Rate of malignancy in MRI-detected probably benign (BI-RADS 3) lesions.

OBJECTIVE: The purpose of this study was to evaluate the malignancy rate in MRI-detected probably benign (BI-RADS 3) lesions in women without a history of breast cancer. MATERIALS AND METHODS: In this study, 1265 patients underwent breast MRI during a 7-year period. One hundred and eight (8.5%) patients with a nonpalpable breast lesion classified as BI-RADS 3 at MRI and with a needle biopsy or adequate follow-up of at least 24 months were included. Statistical analysis included calculation of the negative predictive value with its 95% CI. RESULTS: Of 108 lesions, 107 (99.1%) were correctly assessed as probably benign, resulting in a negative predictive value of 99.1% (95% CI, 94.99-99.98%). Histopathology was requested by the patient or referring physician in 44 patients. Of these, 43 (39.8%) lesions were classified as benign and one (0.9%) as malignant. There were no changes evident in any of the remaining 64 (59.2%) lesions during follow-up (range, 2-9 years). CONCLUSION: In MRI-detected probably benign (BI-RADS 3) lesions, the malignancy rate is low and within the accepted cancer rate for mammographically or sonographically detected BI-RADS 3 lesions. Short-term follow-up MRI at intervals of 6, 12, and 24 months in MRI BI-RADS 3 lesions remains a strong tool with which to detect suspicious lesions. Interval changes in size, morphology, or enhancement are regarded as indicative of malignancy.

Multi-detector CT urography: effect of oral hydration and contrast medium volume on renal parenchymal enhancement and urinary tract opacification--a quantitative and qualitative analysis.

OBJECTIVE: To assess the effect of oral hydration and contrast-medium volume on renal enhancement and urinary tract opacification in multi-detector CT urography. METHODS: A total of 192 patients were assigned to different protocols with varying doses of contrast agent with and without oral hydration. The attenuation was measured in the renal parenchyma in the unenhanced, nephrographic and excretory phase, and in the urinary tract in excretory phase imaging, respectively. Opacification of the urinary tract was graded on volume rendered images. RESULTS: Oral hydration did not significantly alter renal parenchymal enhancement in both the nephrographic and the excretory phase (p > 0.001), but significantly decreased mean attenuation of the urinary tract in the excretory phase (p < or = 0.001), and improved continuous opacification of all ureter segments (p < 0.01). Higher volumes of contrast medium improved renal parenchymal enhancement (p < or = 0.001) and continuous opacification of the urinary tract (p < or = 0.01). CONCLUSION: Oral hydration leads to lower attenuation values in the urinary tract but improves the continuous opacification of the tract. Increase in contrast medium volume leads to higher renal parenchymal enhancement as well as to an increased continuous opacification of the urinary tract. Decrease in contrast medium volume cannot be compensated for by oral hydration in terms of parenchymal enhancement.

3 Tesla breast MR imaging as a problem-solving tool: Diagnostic performance and incidental lesions.

PURPOSE: To investigate the diagnostic performance and incidental lesion yield of 3T breast MRI if used as a problem-solving tool. METHODS: This retrospective, IRB-approved, cross-sectional, single-center study comprised 302 consecutive women (mean: 50±12 years; range: 20-79 years) who were undergoing 3T breast MRI between 03/2013-12/2014 for further workup of conventional and clinical breast findings. Images were read by experienced, board-certified radiologists. The reference standard was histopathology or follow-up ≥ two years. Sensitivity, specificity, PPV, and NPV were calculated. Results were stratified by conventional and clinical breast findings. RESULTS: The reference standard revealed 53 true-positive, 243 true-negative, 20 false-positive, and two false-negative breast MRI findings, resulting in a sensitivity, specificity, PPV, and NPV of 96.4% (53/55), 92.4% (243/263), 72.6% (53/73), and 99.2% (243/245), respectively. In 5.3% (16/302) of all patients, incidental MRI lesions classified BI-RADS 3-5 were detected, 37.5% (6/16) of which were malignant. Breast composition and the imaging findings that had led to referral had no significant influence on the diagnostic performance of breast MR imaging (p>0.05). CONCLUSION: 3T breast MRI yields excellent diagnostic results if used as a problem-solving tool independent of referral reasons. The number of suspicious incidental lesions detected by MRI is low, but is associated with a substantial malignancy rate.

Psoriatic arthritis and rheumatoid arthritis: findings in contrast-enhanced MRI.

OBJECTIVE: Our objective was to define typical MRI findings of the wrist and the hand in patients with psoriatic arthritis (PsA) and rheumatoid arthritis (RA). MATERIALS AND METHODS: Eighteen PsA and 21 RA patients with arthralgia of the wrist or hand joints underwent gadolinium-enhanced MRI of the wrist and hand. Two experienced radiologists interpreted abnormalities in consensus with respect to periarticular soft-tissue swelling, synovitis with or without effusion, periostitis, bone edema, bone erosions, bone cysts, and tenosynovitis. The distribution of the abnormalities also was evaluated. RESULTS: Erosions were statistically more frequent in patients with RA (p < 0.05). Periostitis was statistically seen more frequently in patients with PsA (p < 0.05). No statistically significant difference was found in the frequency of synovitis, bone marrow edema, bone cysts, and tenosynovitis between the two groups (p > 0.05). The radiocarpal joint, the midcarpal joints, the carpometacarpal joints, and the metacarpophalangeal joints were significantly affected more frequently in patients with RA than in patients with PsA (p < 0.05), whereas the proximal interphalangeal joints were significantly more frequently affected in patients with PsA (p < 0.05). CONCLUSION: Periostitis and synovitis of the proximal interphalangeal joints are typical MRI findings in patients with PsA, whereas synovitis with erosions of the wrist, the midcarpal joints, the carpometacarpal joints, and the metacarpophalangeal joints are typical findings in patients with RA.

Breast MRI used as a problem-solving tool reliably excludes malignancy.

PURPOSE: To evaluate the diagnostic performance of breast MRI if used as a problem-solving tool in BI-RADS 0 cases. MATERIAL AND METHODS: In this IRB-approved, single-center study, 687 women underwent high-resolution-3D, dynamic contrast-enhanced breast magnetic resonance imaging (MRI) between January 2012 and December 2012. Of these, we analyzed 111 consecutive patients (mean age, 51 ± 12 years; range, 20-83 years) categorized as BI-RADS 0. Breast MRI findings were stratified by clinical presentations, conventional imaging findings, and breast density. MRI results were compared to the reference standard, defined as histopathology or an imaging follow-up of at least 1 year. RESULTS: One hundred eleven patients with BI-RADS 0 conventional imaging findings revealed 30 (27%) mammographic masses, 57 (51.4%) mammographic architectural distortions, five (4.5%) mammographic microcalcifications, 17 (15.3%) ultrasound-only findings, and two palpable findings without imaging correlates. There were 15 true-positive, 85 true-negative, 11 false-positive, and zero false-negative breast MRI findings, resulting in a sensitivity, specificity, PPV, and NPV of 100% (15/15), 88.5% (85/96), 57.7% (15/26), and 100% (85/85), respectively. Breast density and reasons for referral had no significant influence on the diagnostic performance of breast MRI (p>0.05). CONCLUSION: Breast MRI reliably excludes malignancy in conventional BI-RADS 0 cases resulting in a NPV of 100% (85/85) and a PPV of 57.7% (15/26).

MR arthrography of the shoulder: do we need local anesthesia?

PURPOSE: To assess pain intensity with and without subcutaneous local anesthesia prior to intraarticular administration of contrast medium for magnetic resonance arthrography (MRa) of the shoulder. MATERIALS AND METHODS: This single-center study was conducted after an IRB waiver of authorization, between January 2010 and December 2012. All patients provided written, informed consent for the procedure. Our prospectively populated institutional database was searched, based on our inclusion criteria. There were 249 outpatients (178 men and 71 women; mean age, 44.4 years ± 14.6; range, 15-79) who underwent MRa and were enrolled in this study. Patients were excluded if they had received surgery of the shoulder before MRa, had undergone repeated MRa of the same shoulder, and/or had undergone MRa of both shoulders on the same day. Patients were randomly assigned into one of three groups. Patients in group A (n=61) received skin infiltration with local anesthesia. Patients in control group B (n=92) and group C (n=96) did not receive local anesthesia. Pain levels were immediately assessed after the injection for MRa using a horizontal visual analog scale (VAS) that ranged from 0 to 10. To compare the pain scores of the three groups for male and female patients, a two-way analysis of variance was used. A p-value equal to or less than 0.05 was considered to indicate a significant result. RESULTS: Patients who received local anesthesia (group A) showed a mean pain level on the VAS of 2.6 ± 2.3. In patients who did not receive local anesthetics (groups B and C), a mean pain level on the VAS of 2.6 ± 2.2 and 2.7 ± 2.4 were detected, respectively. Between the three groups, no statistically significant difference in pain intensity was detected (p=.960). There were significant differences in subjective pain perception between men and women (p=.009). Moreover, the sex difference in all three groups was equal (p=.934). CONCLUSION: Local anesthesia is not required to lower a patient's pain intensity when applying intra-articular contrast media for MR arthrography of the shoulder. This could result in reduced costs and a reduced risk of adverse reactions, without an impact on patient comfort.

Prevention of epidural scarring after microdiscectomy: a randomized clinical trial comparing gel and expanded polytetrafluoroethylene membrane.

A randomized clinical trial compared two materials used to prevent epidural scarring after microdiscectomy. To determine whether ADCON-L Gel (ALG) or Preclude Spinal Membrane (PSM) was more effective in preventing scarring, reducing pain, and improving quality of life postoperatively. Postdiscectomy syndrome may result from epidural scarring. Various materials have been used in attempts to prevent this problem, but none have provided optimal results. Previous laboratory and clinical studies have found ALG and PSM to be effective, but none compared the two materials. Thirty-one patients undergoing primary microdiscectomy were randomly assigned to receive either ALG or PSM. Postoperatively, patients were evaluated by magnetic resonance imaging (MRI), with contrast, for volume and rostral-caudal extent of scar tissue and nerve root involvement. Back and leg pain and quality of life were assessed by neurologic examinations and standardized patient surveys. Findings at any reoperations were recorded. Results in the PSM (n = 18) and ALG (n = 13) groups were compared statistically. No operative or postoperative complications occurred. Two patients in each group required reoperation. MRI at 6 months showed no, mild or mild-moderate scarring in most patients, with no significant differences between the ALG and PSM groups in scar volume and extent or nerve root involvement. Neurologic examinations and patient surveys showed substantial reductions in pain over time in both groups but no significant differences between groups. PSM was easy to see and remove at reoperation. PSM and ALG are equally effective in preventing epidural scarring associated with postdiscectomy syndrome.

Routine use of three-dimensional contrast-enhanced moving-table MR angiography in patients with peripheral arterial occlusive disease: comparison with selective digital subtraction angiography.

PURPOSE: To compare the diagnostic accuracy of contrast-enhanced (CE) three-dimensional (3D) moving-table magnetic resonance (MR) angiography with that of selective digital subtraction angiography (DSA) for routine clinical investigation in patients with peripheral arterial occlusive disease. METHODS: Thirty-eight patients underwent CE 3D moving-table MR angiography of the pelvic and peripheral arteries. A commercially available large-field-of-view adapter and a dedicated peripheral vascular phased-array coil were used. MR angiograms were evaluated for grade of arterial stenosis, diagnostic quality, and presence of artifacts. MR imaging results for each patient were compared with those of selective DSA. RESULTS: Two hundred and twenty-six arterial segments in 38 patients were evaluated by both selective DSA and MR angiography. No complications related to MR angiography were observed. There was agreement in stenosis classification in 204 (90.3%) segments; MR angiography overgraded 16 (7%) segments and undergraded 6 (2.7%) segments. Compared with selective DSA, MR angiography provided high sensitivity and specificity and excellent interobserver agreement for detection of severe stenosis (97% and 95%, kappa = 0.9 +/- 0.03) and moderate stenosis (96.5% and 94.3%, kappa = 0.9 +/- 0.03). CONCLUSION: Compared with selective DSA, moving-table MR angiography proved to be an accurate, noninvasive method for evaluation of peripheral arterial occlusive disease and may thus serve as an alternative to DSA in clinical routine.

Adrenocortical carcinomas and adrenal pheochromocytomas: mass and enhancement loss evaluation at delayed contrast-enhanced CT.

PURPOSE: To retrospectively measure the adrenal gland attenuation and the percentage loss of adrenal gland enhancement at delayed contrast medium-enhanced computed tomography (CT) in patients with adrenocortical carcinomas and pheochromocytomas and to compare these data with those in patients with adenomas and metastases. MATERIALS AND METHODS: The study protocol was approved by the ethics committee, which waived informed consent. Eleven patients with proved adrenocortical carcinoma, 17 with proved pheochromocytoma, 23 with adrenal adenoma, and 16 with metastasis to the adrenal gland underwent helical CT. Nonenhanced CT was followed by contrast-enhanced CT 1 minute and 10 minutes later. Attenuation and enhancement loss values were calculated. RESULTS: The mean attenuation of adenomas (8 HU +/- 18 [standard deviation]) was significantly lower than those of adrenocortical carcinomas (39 HU +/- 14), pheochromocytomas (44 HU +/- 11), and metastases (34 HU +/- 11) on nonenhanced CT scans (P < .001). Although the mean attenuation values for nonadenomas (ie, adrenocortical carcinomas, pheochromocytomas, and metastases) were significantly higher than the value for adenomas on the 1-minute contrast-enhanced CT scans (P < .001), there was more overlap in attenuation between adenomas and nonadenomas on contrast-enhanced scans than on nonenhanced scans. On the 10-minute delayed contrast-enhanced scans, the mean attenuation of adenomas (32 HU +/- 17) was significantly lower than the mean attenuations of carcinomas (72 HU +/- 15), pheochromocytomas (83 HU +/- 14), and metastases (66 HU +/- 13) (P < .001). At optimal threshold values of 50% for absolute percentage of enhancement loss and 40% for relative percentage of enhancement loss at 10 minutes, both the sensitivity and the specificity for the diagnosis of adenoma were 100% when adenomas were compared with carcinomas, pheochromocytomas, and metastases. CONCLUSION: The enhancement loss in adrenocortical carcinomas and pheochromocytomas is similar to that in adrenal metastases but significantly less than that in adrenal adenomas. The percentage change in contrast material washout is a useful adjunct to absolute CT attenuation values in differentiating adrenal adenomas from adrenocortical carcinomas and pheochromocytomas.

Radiation-induced osteosarcoma of the chest wall.

A case of radiation-induced sarcoma of the chest wall is reported. Twenty-seven years 11 months after orthovoltage radiotherapy of the right breast a 69-year-old woman developed a radiation-induced osteosarcoma of the right thoracic wall. Initial diagnosis has been T-cell lymphoma of the skin. The right breast was irradiated with tangential fields and a total dose of 40 Gy, 2 Gy/day, 5 days a week. Orthovoltage treatment was performed in two courses of 20 Gy, 3 months apart. The clinical appearance of the secondary sarcoma was a diffuse infiltrated area in the irradiated breast which seemed to be fixed to the chest wall. Magnetic resonance imaging (MRI) demonstrated a mass in the right anterior thoracic wall which destroyed the fourth to the sixth rib. The tumor infiltrated the thoracic wall, including subcutaneous tissue and pericardium, as well as extending into the subphrenic space. Biopsy of the lesion revealed a poorly differentiated osteosarcoma. The patient's general condition precluded surgical or chemotherapeutic intervention; she died due to a cerebral stroke 6 months later. This case fulfilled all criteria for radiation-induced sarcoma, as there was a prior history of radiotherapy, latency period of several years, development of sarcoma within the irradiated field, and histologic confirmation of sarcoma.

Multiplanar spiral CT enterography in patients with Crohn's disease using a negative oral contrast material: initial results of a noninvasive imaging approach.

The aim of this study was to prospectively define the role of multiplanar spiral CT enterography with a new negative oral contrast material for noninvasive assessment of the small bowel in patients with Crohn's disease. Thirty patients with established Crohn's disease prospectively underwent spiral CT enterography at 45-60 min after distension of the small bowel with 1400 ml of a negative oral contrast material (Mucofalk water enema). Spiral CT scans were obtained 50 s after administration of intravenous contrast material with the following parameters: 5-mm collimation; 7.5-mm/s table feed; and 3-mm reconstruction interval. The adequacy of bowel opacification, luminal distension, and the contribution of two-dimensional multiplanar reformatted imaging were assessed by two observers. Spiral CT imaging findings were compared with results of enteroclysis as well as endoscopic and histological findings in all patients. Spiral CT enterography with Mucofalk water enema was well tolerated in 29 of 30 patients. Findings on spiral CT enterography were comparable with those of barium studies in 25 of 30 patients, superior to those on barium studies in 4 patients, and inferior in 1 patient ( p<0.05). The addition of multiplanar reformatted images to axial spiral CT scans significantly improved observers' confidence in image interpretation ( p<0.05) but did not reveal additional abnormalities. Multiplanar spiral CT enterography with Mucofalk excellently provides information in patients with Crohn's disease. This technique accurately depicts the level of small bowel obstruction and the extent of inflammatory small bowel disease and its extraluminal complications.