The relation between ankle morphology and osteochondritis dissecans of talus.

The purpose of this study is to describe, if there is, any relation between ankle morphology and development of talus osteochondritis dissecans (OCD) using certain morphological parameters derived from high resolution magnetic resonance imaging (MRI). Study included a total of 93 patients: 26 patients with traumatic medial talus OCD, 30 patients with idiopathic medial talus OCD and 37 patients with normal ankle as the control group. Five MRI morphological parameters (Maximal Tibial Thickness (MTiTh), Malleolar Width (MalW), Length of Trochlea Tali Arc (TaL), Height of Trochlea Tali Arc (TaH) and Angle of Trochlea Tali Inclination (TaIA)) that are expected to be relevant to talus OCD formation are measured and compared for the three groups. Significant difference was found between the idiopathic and the traumatic group in terms of age and gender. Two of five morphologic parameters (MalW and TaL) also showed significant difference for the traumatic and idiopathic group compared to healthy volunteers. Two morphologic parameters that were found to be significantly different from healthy controls may suggest that ankle morphology be a possible factor for talus OCD. Age and gender difference between the traumatic and idiopathic group also may point out different underlying mechanisms for OCD formation.

Bilateral massive perirenal subcapsular effusion: A case report.

Bilateral perirenal subcapsular effusion is a rare condition with several underlying etiologies. A 27-year-old woman presented with a 3-day history of bilateral flank pain and edema on the dorsum of her feet. Imaging, biochemical, and clinical evaluations revealed bilateral massive perirenal subcapsular effusion secondary to nephrotic syndrome. The patient was successfully treated with bilateral percutaneous drainage. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:597-599, 2017.

Thyroid function and cardiovascular events in chronic kidney disease patients.

BACKGROUND AND AIMS: Abnormalities of thyroid function are commonly seen in chronic kidney disease (CKD) patients. They are associated with adverse clinical conditions such as atherosclerosis, endothelial dysfunction, inflammation and abnormal blood pressure variability. We investigated the association between thyroid disorders and endothelial function, assessed by flow-mediated dilatation (FMD) and carotid intima-media thickness (CIMT), and cardiovascular events (CVE) in CKD patients. MATERIALS AND METHODS: This observational cohort study included 305 CKD (stages 1-5) patients. Routine biochemistry, including free T3, free T4 and thyroid stimulating hormone, fibroblast growth factor-23 (FGF-23) and FMD, CIMT were measured. We divided patients into four groups according to thyroid hormone status: euthyroidism, subclinical hyperthyroidism, subclinical hypothyroidism, and euthyroid sick syndrome. Fatal and composite CVE were recorded for a median 29 months. RESULTS: Patients with subclinical hypothyroidism had a higher prevalence of hypertension and diabetes and also were more likely to have higher values of systolic CIMT, phosphorus, intact parathormone (iPTH), FGF-23, homeostasis model assessment-insulin resistance and lower levels of FMD than euthyroid patients. In the unadjusted survival analysis, subclinical hypothyroidism and euthyroid sick syndrome were associated with an increased risk for the outcome as compared with euthyroidism [hazard ratio 30.63 (95 % confidence interval 12.27-76.48) and 12.17 (3.70-39.98), respectively]. The effects of subclinical hypothyroidism and euthyroid sick syndrome were maintained even in fully adjusted models. CONCLUSION: We demonstrated that subclinical hypothyroidism and euthyroid sick syndrome are associated with increased CVE in CKD patients. Further studies are needed to explore these issues.

Imaging Findings of Jugular Foramen Meningocele in a Neurofibromatosis Type 1 Patient.

Neurofibromatosis type I (NF1) is a neurocutaneous disorder that involves autosomal dominant transmission. Skull defects, including sphenoid dysplasia and calvarial defects, are a rare finding in patients with NF1. Spinal meningocele and sphenoid wing dysplasia have been identified in NF1 but the occurrence of meningoceles at the skull base is extremely rare. A rare instance of jugular foramen meningocele being identified in an NF1 patient on imaging is described in this paper. To the best of our knowledge, only two such cases have been reported in the English literature.

The value of qualitative and quantitative assessment of lesion to cerebral cortex signal ratio on double inversion recovery sequence in the differentiation of demyelinating plaques from non-specific T2 hyperintensities.

OBJECTIVES: To assess the usefulness of the visual assessment and to determine diagnostic value of the lesion-to-cerebral cortex signal ratio (LCSR) measurement in the differentiation of demyelinating plaques and non-specific T2 hyperintensities on double inversion recovery (DIR) sequence. MATERIAL AND METHODS: DIR and fluid-attenuated inversion recovery (FLAIR) sequences of 25 clinically diagnosed multiple sclerosis (MS) patients and 25 non-MS patients with non-specific T2-hyperintense lesions were evaluated visually and LCSRs were measured by two observers independently. RESULTS: On DIR sequence, the calculated mean LCSR ± SD for demyelinating plaques and non-specific T2-hyperintense lesions were 1.60 ± 0.26 and 0.75 ± 0.19 for observer1, and 1.61 ± 0.27 and 0.74 ± 0.19 for observer2. LCSRs of demyelinating plaques were significantly higher than other non-specific T2-hyperintense lesions on DIR sequence. By using the visual assessment demyelinating plaques were differentiated from non-specific T2-hyperintensities with 92.8 % sensitivity, 97.5 % specificity and 95.1 % accuracy for observer1 and 92.8 % sensitivity, 95 % specificity and 93.9 % accuracy for observer2. CONCLUSION: Visual assessment and LCSR measurement on DIR sequence seems to be useful for differentiating demyelinating MS plaques from supratentorial non-specific T2 hyperintensities. This feature can be used for diagnosis of MS particularly in patients with only supratentorial T2-hyperintense lesions who are categorized as radiologically possible MS. KEY POINTS: • Demyelinating plaques and non-specific T2-hyperintensities have different SI on DIR images. • These differences can be assessed by LCSR measurement or visual assessment. • There is an excellent inter-observer agreement for both methods. • This feature can be used in radiologically possible MS cases.

Collapsing Glomerulopathy in a Child with Galloway-Mowat Syndrome.

Galloway-Mowat syndrome (GMS) is an autosomal recessive disorder with a poor prognosis that was first defined as a triad of central nervous system involvement, hiatal hernia, and nephrotic syndrome. However, this syndrome is now known to have a heterogeneous clinical presentation. The nephrotic syndrome is steroid resistant and is responsible for the outcome. The combination of collapsing glomerulopathy and GMS is very rare. A 26-month-old boy presented with steroid-resistant nephrotic syndrome associated with neurologic findings, including microcephaly, psychomotor retardation, and nystagmus. Magnetic resonance imaging showed marked cerebral atrophy, optic atrophy, and hypomyelination. A renal biopsy was consistent with collapsing glomerulopathy. If collapsing glomerulopathy is associated with neurological abnormalities, especially with microcephaly, clinicians should consider GMS as a possible underlying cause.

Bayesian segmentation of human facial tissue using 3D MR-CT information fusion, resolution enhancement and partial volume modelling.

BACKGROUND: Accurate segmentation of human head on medical images is an important process in a wide array of applications such as diagnosis, facial surgery planning, prosthesis design, and forensic identification. OBJECTIVES: In this study, a Bayesian method for segmentation of facial tissues is presented. Segmentation classes include muscle, bone, fat, air and skin. METHODS: The method presented incorporates information fusion from multiple modalities, modelling of image resolution (measurement blurring), image noise, two priors helping to reduce noise and partial volume. Image resolution modelling employed facilitates resolution enhancement and superresolution capabilities during image segmentation. Regularization based on isotropic and directional Markov Random Field priors is integrated. The Bayesian model is solved iteratively yielding tissue class labels at every voxel of the image. Sub-methods as variations of the main method are generated by using a combination of the models. RESULTS: Testing of the sub-methods is performed on two patients using single modality three-dimensional (3D) image (magnetic resonance, MR or computerized tomography, CT) as well as registered MR-CT images with information fusion. Numerical, visual and statistical analyses of the methods are conducted. High segmentation accuracy values are obtained by the use of image resolution and partial volume models as well as information fusion from MR and CT images. The methods are also compared with our Bayesian segmentation method proposed in a previous study. The performance is found to be similar to our previous Bayesian approach, but the presented methods here eliminates ad hoc parameter tuning needed by the previous approach which is system and data acquisition setting dependent. CONCLUSIONS: The Bayesian approach presented provides resolution enhanced segmentation of very thin structures of the human head. Meanwhile, free parameters of the algorithm can be adjusted for different imaging systems and data acquisition settings in a more systematic way as compared with our previous study.

Brain herniations into the dural venous sinus or calvarium: MRI findings, possible causes and clinical significance.

OBJECTIVES: To determine frequency, imaging features and clinical significance of herniations of brain parenchyma into dural venous sinuses (DVS) and/or calvarium found on MRI. METHODS: A total of 6160 brain MRI examinations containing at least one high-resolution T1- or T2-weighted sequence were retrospectively evaluated to determine the presence of incidental brain herniations into the DVS or calvarium. MRI sequences available for review were evaluated according to their capability to demonstrate these herniations. Patients' symptoms and clinical findings were recorded. RESULTS: Twenty-one (0.32 %) brain parenchyma herniations into the DVS (n = 18) or calvarium (n = 3) in 20 patients were detected. The most common locations of the herniations were the transverse sinuses (n = 13) and those involving inferior gyrus of the temporal lobe (n = 9). High-resolution T1- and T2-weighted sequences were equally useful in the detection of these brain herniations. According to clinical symptoms, brain herniations were considered to be incidental but headaches were present in nine patients. CONCLUSION: Brain herniations with surrounding cerebrospinal fluid (CSF) into the DVS and/or calvarium are incidental findings and not proven to be associated with any symptoms. Although rare, these herniations are more common than previously recognized and should not be confused with arachnoid granulations, clots or tumours. KEY POINTS: • Brain herniations into the DVS are more common than previously assumed. • The most frequent locations are the transverse sinus. • These herniations are incidental findings. • The relationship between brain herniation into DVS and headache is uncertain. • High-resolution MR sequences are most useful in detection of brain herniations.

MRI diagnosis of dural sinus - Cortical venous thrombosis: Immediate post-contrast 3D GRE T1-weighted imaging versus unenhanced MR venography and conventional MR sequences.

OBJECTIVE: Primary aim is to compare the diagnostic value of contrast-enhanced 3D GRE T1-weighted sequences with unenhanced MR venography and conventional magnetic resonance imaging (MRI), in detection of dural venous sinus (DVS) and cortical venous thrombosis; secondary aim is to determine the relationship between DVS thrombosis/site and gender, age, infarction or hemorrhage. METHODS: We retrospectively reviewed conventional MR images, unenhanced MR venography and immediate post-contrast 3D GRE T1-weighted MR images in 30 patients (17 male and 13 female, 21-70 years old, mean age 40.1) with clinically suspected DVS thrombosis. MR examinations had been performed with 1.5T or 3T MR Scanners. DVSs were evaluated in 10 sub-segments, including cortical veins. Each set of MR images were examined separately, blinded to the final diagnosis. Associated findings were also noted and sensitivity, specificity and accuracy of each MRI technique were calculated. RESULTS: Final diagnosis of cortical venous and/or dural sinus thrombosis was established in 24 (80%) of 30 cases and 67 (22.3%) out of 300 segments. For detection of the thrombotic segment, sensitivity, specificity, and accuracy were 83.6%, 95.3%, and 92.7% by conventional MR sequences, 89.6%, 91.8%, and 91.3% by unenhanced MR venography, and 92.5%, 100%, and 98.3% by contrast-enhanced 3D GRE T1-weighted sequence, respectively. Infarction and hemorrhage were more frequent in cases with cortical venous thrombosis, while gender and age had no significant relation with DVS thrombosis or its site. Conventional MR sequences and unenhanced MR venography were helpful due to additional information they provided in some cases with isolated cortical venous thrombosis, with hyperintense thrombus material and with associated hemorrhage or infarction. CONCLUSION: Contrast-enhanced 3D GRE T1-weighted MRI is the most accurate imaging method for the detection of DVS and/or cortical venous thrombosis. Infarction and hemorrhage were more frequent in cases with cortical venous thrombosis.