Dual-energy CT-generated bone marrow oedema maps improve timely visualisation and recognition of acute lower extremity fractures.

AIM: To assesses whether utilising bone marrow oedema (BMO) maps improved fracture read times and reader confidence in a large series of acute lower extremity trauma dual-energy computed tomography (DECT) studies. MATERIALS AND METHODS: One hundred and six DECT studies, including 60 fracture cases and 46 non-fracture cases, were evaluated retrospectively in this cross-sectional study. Three-dimensional (3D) BMO maps were generated for each study and coded to display skeletal anatomy in blue and marrow oedema in green. Studies were interpreted by two readers in two timed stages (without and with BMO maps). Readers identified the number, anatomical location, and comminution of fractures. Reader confidence (five-point Likert scale) for fracture identification and anatomical regions where oedema was present was also recorded. RESULTS: Decreased read times (p<0.01) were observed when readers utilised BMO maps for their fracture search. The presence of oedema on BMO maps corresponded with associated fracture in 75.7% reads. No differences in reader confidence were observed as a result of using this BMO-guided technique (>95%, 5/5 for both readers with and without the aid of BMO maps). CONCLUSIONS: DECT BMO maps improve the speed of radiological identification of suspected acute lower extremity fractures with preserved reader confidence. It may help emergent detection of fractures, important for patient management and outcomes.

Evaluation of giant cell tumors by diffusion weighted imaging-fractional ADC analysis.

BACKGROUND: A single ADC value is used in clinical practice on multi b-value acquisitions. Low b-value acquisitions are affected by intravoxel incoherent motion, which is dependent on perfusion. Giant cell tumors (GCTs) are known to exhibit early arterial enhancement and low ADC values. Mean, minimum and fractional ADC characteristics of osseous and tenosynovial GCTs are systematically evaluated. METHODS: Tenosynovial and osseous GCTs were included. Each lesion was evaluated on conventional MRI and DWI by two musculoskeletal radiologists. ADC was measured by placing an ROI on the most confluent enhancing portion of the lesion. Fractional and best fit ADC calculations were performed using MATLAB software. RESULTS: No statistically significant difference was found between tenosynovial and osseous lesions' ADC values. Mean ADC for all lesions was 1.0 × 10-3 mm2/s (SD = 0.2 × 10-3 mm2/s) and minimum ADC was 0.5 × 10-3 mm2/s (SD = 0.3 × 10-3 mm2/s). Average mean ADC value obtained from B50-B400 slope was 1.1 × 10-3 mm2/s (SD = 0.2 × 10-3 mm2/s), and the average mean ADC value obtained from B400-B800 slope was 0.8 × 10-3 mm2/s (SD = 0.1 × 10-3 mm2/s) [p-value <0.01]. CONCLUSION: Tenosynovial and osseous GCTs demonstrate similar and low ADC values, which become even lower when using high b-value pairs. Our study also supports the theory of intravoxel incoherent motion that becomes apparent at low b values as related to giant cell tumors, which are known to be hyperperfused.

Impact of high resolution 3 tesla MR neurography (MRN) on diagnostic thinking and therapeutic patient management.

OBJECTIVE: To evaluate the impact of magnetic resonance neurography (MRN) on diagnostic thinking and therapeutic choices in patients with suspected peripheral neuropathy. METHODS: IRB approval was obtained for this HIPAA-compliant study. Questionnaires were administered to six surgeons regarding the diagnosis and treatment in 85 patients suspected of having peripheral neuropathy, before (pretest) and after (posttest) MRN. Multiple outcome measures related to diagnostic confidence and surgical decision-making were assessed. RESULTS: The final cohort included 81 patients (30 men and 51 women, age 47 ± 17 years). The following changes were observed from pretest to posttest questionnaires: 23% in nerve involvement (P < 0.05), 48% in degree of confidence of nerve involvement (P < 0.01), 27% in grade of injury (P < 0.05), 33% in differential diagnosis (P < 0.05), 63% in degree of confidence in need for surgery (P < 0.001), 41% in timing of surgery (P < 0.01), 30% in approach to surgery (P < 0.05), 58% in degree of confidence in approach to surgery (P < 0.001), 30% in estimated length of surgery (P < 0.05) and 27% in length of incision (P < 0.05). The dichotomous decision regarding surgical or nonsurgical treatment changed from pro to con in 17%. CONCLUSION: MRN results significantly influenced the diagnostic thinking and therapeutic recommendations of peripheral nerve surgeons. KEY POINTS: • In patients with peripheral neuropathy, MRN significantly impacts diagnostic thinking. • In patients with peripheral neuropathy, MRN significantly impacts therapeutic choices. • 3-T MRN should be considered in presurgical planning of patients with peripheral neuropathy.

High-resolution 3T MR neurography of the brachial plexus and its branches, with emphasis on 3D imaging.

With advancement in 3D imaging, better fat-suppression techniques, and superior coil designs for MR imaging and the increasing availability and use of 3T magnets, the visualization of the complexity of the brachial plexus has become facile. The relevant imaging findings are described for normal and pathologic conditions of the brachial plexus. These radiologic findings are supported by clinical and/or EMG/surgical data, and corresponding high-resolution MR neurography images are illustrated. Because the brachial plexus can be affected by a plethora of pathologies, resulting in often serious and disabling complications, a better radiologic insight has great potential in aiding physicians in rendering superior services to patients.

Anatomic MR imaging and functional diffusion tensor imaging of peripheral nerve tumors and tumorlike conditions.

BACKGROUND AND PURPOSE: A number of benign and malignant peripheral nerve tumor and tumorlike conditions produce similar imaging features on conventional anatomic MR imaging. Functional MR imaging using DTI can increment the diagnostic performance in differentiation of these lesions. Our aim was to evaluate the role of 3T anatomic MR imaging and DTI in the characterization of peripheral nerve tumor and tumorlike conditions. MATERIALS AND METHODS: Twenty-nine patients (13 men, 16 women; mean age, 41±18 years; range, 11-83 years) with a nerve tumor or tumorlike condition (25 benign, 5 malignant) underwent 3T MR imaging by using anatomic (n=29), functional diffusion, DWI (n=21), and DTI (n=24) techniques. Images were evaluated for image quality (3-point scale), ADC of the lesion, tractography, and fractional anisotropy of nerves with interobserver reliability in ADC and FA measurements. RESULTS: No significant differences were observed in age (benign, 40±18 versus malignant, 45±19 years) and sex (benign, male/female=12:12 versus malignant, male/female=3:2) (P>.05). All anatomic (29/29, 100%) MR imaging studies received "good" quality; 20/21 (95%) DWI and 21/24 (79%) DTI studies received "good" quality. ADC of benign lesions (1.848±0.40×10(-3) mm2/s) differed from that of malignant lesions (0.900±0.25×10(-3) mm2/s, P<.001) with excellent interobserver reliability (ICC=0.988 [95% CI, 0.976-0.994]). There were no FA or ADC differences between men and women (P>.05). FA of involved nerves was lower than that in contralateral healthy nerves (P<.001) with excellent interobserver reliability (ICC=0.970 [95% CI, 0.946-0.991]). ADC on DTI and DWI was not statistically different (P>.05), with excellent intermethod reliability (ICC=0.943 [95% CI, 0.836-0.980]). Tractography differences were observed in benign and malignant lesions. CONCLUSIONS: 3T MR imaging and DTI are valuable methods for anatomic and functional evaluation of peripheral nerve lesions with excellent interobserver reliability. While tractography and low FA provide insight into neural integrity, low diffusivity values indicate malignancy in neural masses.

Susceptibility-weighted imaging (SWI): a potential non-invasive imaging tool for characterizing ischemic brain injury?

Susceptibility-weighted imaging (SWI) is a new high-resolution magnetic resonance imaging (MRI) tool that uses the paramagnetic susceptibility effects of deoxygenated blood to study the intracranial venous vasculature. We present SWI imaging findings in two children who suffered from acute arterial ischemia. Various patterns of normal/altered venous drainage could be identified. Our case study suggests that SWI assisted mapping of the regional changes of the cerebral venous drainage and correlation with diffusion weighted MRI may identify critically perfused brain at risk for infarct progression. Prospective studies are mandatory to further validate the value of SWI.

Folic acid efficacy as an alternative drug added to sodium valproate in the treatment of acute phase of mania in bipolar disorder: a double-blind randomized controlled trial.

OBJECTIVE: The purpose of this study was to evaluate the efficacy of adding folic acid to sodium valproate in the acute phase of mania. METHOD: Following a double-blind randomized controlled trial, 88 clinically manic patients with diagnosis of type I bipolar disorder (BID) were divided randomly into two groups (case and control). The case group was treated with folic acid and sodium valproate and the control group with sodium valproate and placebo. The severity of mania was assessed using the Young Mania Rating Scale (YMRS) at the beginning and end of the first, second and third weeks of the study. RESULTS: The case group's mean manic YMRS measurements (SD) before the initiation of therapy and in the first, second and third weeks of treatment were 34.0 +/- 7.7, 26.7 +/- 2.1, 18.1 +/- 2.1 and 7.1 +/- 0.9 respectively. The control group's measurements were 34.7 +/- 3.8, 27.3 +/- 2.3, 20.7 +/- 2.5 and 10.1 +/- 1.1. There was a statistically significant difference in YMRS scaling results between the case and control groups after 3 weeks of treatment (7.1 +/- 0.9 vs. 10.1 +/- 1.1, P = 0.005). CONCLUSION: Based on our findings, folic acid seems to be an effective adjuvant to sodium valproate in the treatment of the acute phase of mania in patients with bipolar disorder.