Comparison of lateral neck X-ray to neck CT in patients with suspicious bone impaction: "Old habits die hard".

OBJECTIVE: Bone impaction (BI) is a common cause for emergency room visits. Among foreign bodies, fish bone is considered the most common. The sensitivity of symptoms in predicting BI is relatively low, making imaging a central tool to aid diagnosis. Current imaging practices include both neck plain film radiography and none-contrast CT scans of the neck. We evaluated the accuracy of neck plain film radiography and CT scans of the neck for the diagnosis of BI. METHODS: Retrospective review of all patients who presented to the emergency room between 2009 and 2016 with a suspicious history of BI whom underwent plain film neck radiography or CT. All Images were reviewed by two neuro-radiologist blinded to the clinical symptoms and findings. Symptoms, clinical findings and images results were compared to the final diagnosis. RESULTS: 89 patients (30.7%), out of 290 patients who presented with complaints of BI, were diagnosed with BI. Mean age was 44.7 years old. Plain film neck radiography failed to predict BI (sen. 14.4%, spe 89.8% accuracy 63.2%), neck CT has an improved accuracy and sensitivity in locating BI (sen. 83.3%, spe. 94.1% accuracy 92.5%). Interobserver agreement between the two neuro-radiologists was moderate (0.46) and substantial (0.77) in neck radiography and CT images, respectively. Neck radiography missed 60 (out of 61) oropharyngeal BI's. CONCLUSION: Neck radiography has high inter-observer variability and low sensitivity for the diagnosis of BI. Neck CT should be the first imaging modality in patients with suspicious complaints for BI and negative physical exam.

Neurite density of white matter significantly correlates with tuberous sclerosis complex disease severity.

OBJECTIVE: To assess whether white matter (WM) diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI) derived measures correlate with tuberous sclerosis complex (TSC) disease severity. COHORT AND METHODS: A multi-shell diffusion protocol was added to the clinical MRI brain scans of thirteen patients including 6 males and 7 females with a mean ± std age of 17.2 ± 5.8 years. Fractional anisotropy (FA) and mean diffusivity (MD) were generated from DTI and neurite density index (NDI), orientation dispersion index (ODI) and free water index (fiso) were generated from NODDI. A clinical score was determined for each patient according to the existence of epilepsy, developmental delay, autism or psychiatric disorders. Whole-brain segmented WM was averaged for each parametric map and 3 group k-means clustering was performed on the NDI and FA maps. MRI quantitative parameters were correlated with the clinical scores. RESULTS: Segmented whole brain WM averages of MD and NDI values showed significant negative (p = 0.0058) and positive (p = 0.0092) correlations with the clinical scores, respectively. Additionally, the contribution of the low and high NDI-based clusters to the whole brain WM significantly correlated with the clinical scores (p = 0.03 and p = 0.00047, respectively). No correlation was found when the clusters were based on the FA maps. CONCLUSION: Advanced diffusion MRI of TSC patients revealed widespread WM alterations. Neurite density showed significant correlations with disease severity and is therefore suggested to reflect an underlying biological process in TSC WM. The quantification of WM alterations by advanced diffusion MRI may be an additional biomarker for TSC and may be advantageous as a complementary MR protocol for the evaluation of TSC patients.

Anisotropic neural deblurring for MRI acceleration.

PURPOSE: MRI has become the tool of choice for brain imaging, providing unrivalled contrast between soft tissues, as well as a wealth of information about anatomy, function, and neurochemistry. Image quality, in terms of spatial resolution and noise, is strongly dependent on acquisition duration. A typical brain MRI scan may last several minutes, with total protocol duration often exceeding 30 minutes. Long scan duration leads to poor patient experience, long waiting time for appointments, and high costs. Therefore, shortening MRI scans is crucial. In this paper, we investigate the enhancement of low-resolution (LR) brain MRI scanning, to enable shorter acquisition times without compromising the diagnostic value of the images. METHODS: We propose a novel fully convolutional neural enhancement approach. It is optimized for accelerated LR MRI acquisitions obtained by reducing the acquisition matrix size only along phase encoding direction. The network is trained to transform the LR acquisitions into corresponding high-resolution (HR) counterparts in an end-to-end manner. In contrast to previous neural-based MRI enhancement algorithms, such as DAGAN, the LR images used for training are real acquisitions rather than smoothed, downsampled versions of the HR images. RESULTS: The proposed method is validated qualitatively and quantitatively for an acceleration factor of 4. Favourable comparison is demonstrated against the state-of-the-art DeblurGAN and DAGAN algorithms in terms of PSNR and SSIM scores. The result was further confirmed by an image quality rating experiment performed by four senior neuroradiologists. CONCLUSIONS: The proposed method may become a valuable tool for scan time reduction in brain MRI. In continuation of this research, the validation should be extended to larger datasets acquired for different imaging protocols, and considering several MRI machines produced by different vendors.

The Need to Look for Visual Deficit After Stroke in Children.

Purpose: To evaluate the role of the ophthalmologist in the management of children with arterial stroke, at presentation and during follow-up. Methods: This retrospective case series comprised children with arterial stroke who were followed for at least 12 months in a tertiary pediatric medical center in 2005-2016. Demographic data and findings on radiological neuroimaging and ophthalmological and neurological examination were retrieved from the medical files. Results: The cohort included 26 children with stroke. Underlying disorders included metabolic syndrome (n = 5, 19.2%), cardiac anomaly or Fontan repair (n = 3 each, 11.5%), vascular anomaly (n = 3, 11.5%), head trauma with traumatic dissection (n = 3, 11.5%), and hypercoagulability (n = 1, 3.8%); in eight patients (30.8%), no apparent cause was found. Eleven patients (42.3%) had a non-ophthalmological neurological deficit as a result of the stroke. Eye examination was performed in nine patients (34.6%) during follow-up. Ophthalmological manifestations included hemianopic visual field defect in seven patients (7.7%) and complete blindness and poor visual acuity in one patient each (3.8%). At the last visit, no change in visual function was detected. Conclusion: The variable etiology and presentation of pediatric stroke may mask specific visual signs. Children with arterial stroke should be referred for early ophthalmological evaluation and visual rehabilitation.

Noncirrhotic Extrahepatic Portosystemic Shunt Causing Adult-Onset Encephalopathy Treated with Endovascular Closure.

A 54-year-old woman presented with a six-month history of episodic confusion and progressive ataxia. A comprehensive metabolic panel was notable for elevated values of alkaline phosphatase (161 U/L), total bilirubin (1.5 mg/dL), and serum ammonia of 300 umol/L (normal range 9-47). Hepatitis panel, relevant serological tests, tumor markers (CA-19-9, CEA), and urea cycle enzyme studies were unrevealing. Lactulose and rifaximin therapy failed to normalize serum ammonia levels. Imaging revealed a structural vascular abnormality communicating between an enlarged inferior mesenteric vein and the left renal vein, measuring 16 mm in greatest diameter. The diagnosis of congenital extrahepatic portosystemic shunt was made and endovascular shunt closure was performed using a 22 mm Amplatzer II vascular plug. Within a day, serum ammonia levels normalized. Lactulose and rifaximin were discontinued, and confusion and ataxia resolved.