3-T MR neurography of lumbo-sacral plexus in hereditary transthyretin-related amyloidosis with polyneuropathy.

OBJECTIVES: Our aim was to evaluate the ability of magnetic resonance neurography (MRN) of the lumbo-sacral plexus (LSP) to distinguish patients with hereditary transthyretin-related amyloidosis with polyneuropathy (ATTRv-PN) from asymptomatic variant carriers (AVC) and healthy controls and to assess its prognostic value. METHODS: Three-Tesla MRN was performed in 25 consecutive ATTRv-PN patients, 18 AVC, and 10 controls including T2-w DIXON and DWI MR sequences. Two blinded readers independently assessed LSP root diameter and intraneural signal on the MRN images of each subject. MRN findings were compared between groups and correlated with clinical impairment scored on the Neuropathy Impairment Score (NIS) and the modified Polyneuropathy Disability score (mPND). RESULTS: The agreement between readers on MRN images was excellent (Cohen's kappa = 0.82). LSP root enlargement was significantly more frequent in ATTRv-PN patients compared to AVC (ratio = 4.38, p = 0.038). Increased LSP root intraneural signal on T2-w images was significantly more frequent in ATTRv-PN patients compared to AVC (ratio = 3.4, p = 0.016). In contrast, there were no MRN abnormalities in controls. In ATTRv-PN patients, LSP root enlargement was associated with higher mPND scores (p = 0.03) and increased intraneural signal on T2-w images was associated with significantly higher NIS and mPND scores (p = 0.004 and 0.02, respectively). CONCLUSIONS: MRN of the LSP can help differentiate ATTRv-PN patients from AVC. LSP root enlargement and increased intraneural signal are significantly associated with clinical impairment, suggesting potential implications for patient care. KEY POINTS: • ATTRv-PN patients showed abnormal LSP changes on MRN. • MRN of the LSP can help to differentiate ATTRv-PN patients from AVC and healthy controls. • LSP root enlargement and increased intraneural signal were significantly associated with clinical impairment in ATTRv-PN patients.

Anastomotic leakage after colorectal surgery: diagnostic accuracy of CT.

OBJECTIVES: To evaluate the diagnostic accuracy of CT in postoperative colorectal anastomotic leakage (AL). METHODS: Two independent blinded radiologists reviewed 153 CTs performed for suspected AL within 60 days after surgery in 131 consecutive patients, with (n = 58) or without (n = 95) retrograde contrast enema (RCE). Results were compared to original interpretations. The reference standard was reoperation or consensus (a radiologist and a surgeon) regarding clinical, laboratory, radiological, and follow-up data after medical treatment. RESULTS: AL was confirmed in 34/131 patients. For the two reviewers and original interpretation, sensitivity of CT was 82 %, 87 %, and 71 %, respectively; specificity was 84 %, 84 %, and 92 %. RCE significantly increased the positive predictive value (from 40 % to 88 %, P = 0.0009; 41 % to 92 %, P = 0.0016; and 40 % to 100 %, P = 0.0006). Contrast extravasation was the most sensitive (reviewers, 83 % and 83 %) and specific (97 % and 97 %) sign and was significantly associated with AL by univariate analysis (P < 0.0001 and P < 0.0001). By multivariate analysis with recursive partitioning, CT with RCE was accurate to confirm or rule out AL with contrast extravasation. CONCLUSIONS: CT with RCE is accurate for diagnosing postoperative colorectal AL. Contrast extravasation is the most reliable sign. RCE should be performed during CT for suspected AL. KEY POINTS: • CT accurately diagnosed clinically suspected colorectal AL and showed good interobserver agreement • Contrast extravasation was the most sensitive and specific CT sign • Retrograde contrast enema during CT improved positive predictive value • Retrograde contrast enema decreased false-negative or indeterminate original CT interpretations.

Fluid-attenuated inversion recovery vascular hyperintensities are not visible using 3D CUBE FLAIR sequence.

OBJECTIVE: Fluid-attenuated inversion recovery (FLAIR) vascular hyperintensities (FVH), initially described on 2D FLAIR images, are a useful imaging marker in patients with acute ischaemic stroke. We aimed to compare the sensitivity of the 3D CUBE FLAIR sequence with 2D FLAIR for the detection of FVH. METHODS: Forty-seven consecutive patients admitted for a suspected stroke were explored by 2D and 3D CUBE FLAIR MR sequences at 1.5 and 3 T. Three blinded readers assessed FVH defined as hyperintensities within cerebral arteries. Location of FVH, acute brain infarct and arterial stenosis were also assessed. 2D images were compared with 3D images for the detection of FVH. Agreement between readers was assessed. RESULTS: Of the 47 patients, 21 FVHs were observed on 2D FLAIR images of 15 patients (11 with acute brain infarct and 11 with an arterial stenosis). No FVH was visualised on 3D CUBE FLAIR images for either proximal or distal locations. Agreement between readers was excellent. CONCLUSION: FVHs are not visible using 3D CUBE FLAIR images. This study suggests that, in suspected acute ischaemic stroke, the assessment of FVH should only be performed on conventional 2D FLAIR images. KEY POINTS: • Fluid-attenuated inversion recovery (FLAIR) vascular hyperintensities (FVH) are of neuroradiological importance. • FVHs are useful imaging markers in patients with an acute ischaemic stroke. • FVHs are not visible using 3D CUBE FLAIR images. • Assessment of FVH should be performed on conventional 2D FLAIR images.

Computed tomography of the anterior skull base in Kallmann syndrome reveals specific ethmoid bone abnormalities associated with olfactory bulb defects.

CONTEXT: Kallmann syndrome (KS) is characterized by congenital hypogonadotropic hypogonadism (CHH) and an impaired sense of smell related to defective development of the olfactory system. OBJECTIVE: The aim of the study was to use high-resolution computed tomography (CT) to detect specific abnormalities in the ethmoid bone region surrounding the olfactory bulbs in patients with KS. PATIENTS: Thirty-seven KS patients were compared to normosmic CHH (nCHH) patients (n = 15) and controls (n = 30) of similar age. DESIGN AND METHODS: We conducted a prospective study in a single referral center. Subjects underwent CT in bone windows with axial, coronal, and sagittal reconstructions centered on the olfactory fossa (OF) and cribriform plate (CP). We characterized the OF structure by measuring OF height, width, and surface area and a series of angles. The CP foramina were counted bilaterally. Olfactory bulb magnetic resonance imaging, performed in parallel, was compared with CT findings. RESULTS: OF height, width, and surface area were all significantly lower in KS patients than in nCHH patients and controls (P < .0001). KS patients also had wider angles than nCHH patients and controls (P < .0001). KS subjects with olfactory bulb agenesis on magnetic resonance imaging or who harbored KAL1 mutations had the most marked changes in OF measurements and angles. Coronal OF height distinguished KS patients from controls with the best sensitivity and specificity. The mean number of CP foramina was similar in KS, nCHH, and control subjects. CONCLUSIONS: KS is associated with specific ethmoid bone abnormalities. The preserved number of CP foramina in KS patients suggests that the integrity of olfactory structures is not mandatory for their formation during fetal development or their maintenance in adult life.