Saurabh Guleria

Retrograde Wallerian degeneration of cranial corticospinal tracts in cervical spinal cord injury patients using diffusion tensor imaging

Diffusion tensor imaging (DTI) has the potential to reveal disruption of white matter microstructure in chronically injured spinal cords. We quantified fractional anisotropy (FA) and mean diffusivity (MD) to demonstrate retrograde Wallerian degeneration (WD) of cranial corticospinal tract (CST) in cervical spinal cord injury (SCI). Twenty‐two patients with complete cervical SCI in the chronic stage were studied with DTI along with 13 healthy controls. Mean FA and MD values were computed for midbrain, pons, medulla, posterior limb of internal capsule, and corona radiata. Significant reduction in the mean FA and increase in MD was observed in the cranial CST in patients with SCI compared with controls, suggesting retrograde WD. Statistically significant inverse FA and MD changes were noted in corona radiata, indicating some restoration of spared white matter tracts. Temporal changes in the DTI metrics suggest progressing degeneration in different regions of CST. These spatiotemporal changes in DTI metrics suggest continued WD in injured fibers along with simultaneous reorganization of spared white matter fibers, which may contribute to changing neurological status in chronic SCI patients.

Myelin, Myelination, and Corresponding Magnetic Resonance Imaging Changes

Accurate diagnosis of white matter diseases requires a thorough understanding of white matter maturation. These maturational changes are complex and require knowledge of the histologic background and time course of development. This article reviews the in vivo magnetic resonance (MR) appearance of myelination with emphasis on the appearance of different regions of the brain using various pulse sequences at different developmental time points. The appearance of white matter, using the MR pulse sequences that have been shown to be most useful during the stages of myelination, is also discussed.

Towards Establishing a Standardized Magnetic Resonance Imaging Scoring System for Temporomandibular Joints in Juvenile Idiopathic Arthritis

The temporomandibular joints (TMJs) are frequently affected in children with juvenile idiopathic arthritis (JIA). Early detection is challenging, as major variation is present in scoring TMJ pathology on magnetic resonance imaging (MRI). Consensus‐driven development and validation of an MRI scoring system for TMJs has important clinical utility in timely improvement of diagnosis and serving as an outcome measure. We report on a multi‐institutional collaboration toward developing a TMJ MRI scoring system for JIA.

A Simplified Algorithm for Diagnosis of Spinal Cord Lesions

Neuroimaging is indispensable for evaluation of Myelopathy not only for localization but also for etiologic determination. MRI is the preferred examination for further characterization of the majority of these conditions. These include traumatic, inflammatory, infections, compressive and neoplastic conditions. This article provides an overview of a variety of pathologies that afflict the spinal cord in an easy to understand format. Their respective imaging manifestations on MRI and differential diagnoses are focused in this review. Early diagnosis and treatment of Myelopathy is critical in preventing or arresting neurological morbidity.

Magnetic Resonance Imaging Findings following Intraarticular Infliximab Therapy for Refractory Temporomandibular Joint Arthritis among Children with Juvenile Idiopathic Arthritis.

Objective. To evaluate the involvement of intraarticular (IA) infliximab (IFX) in the management of temporomandibular joint (TMJ) arthritis associated with juvenile idiopathic arthritis (JIA) that is refractory to systemic treatment and IA corticosteroid therapy. Methods. Ours was a retrospective study of children with JIA who received IA IFX into the TMJ. The effectiveness of treatment on the progression of acute and chronic changes was assessed by a quantitative magnetic resonance imaging scoring system. Results. Median acute and chronic scores worsened by 0.25 and 0.75, respectively. In multivariate analysis, worsening acute scores and passage of time predicted worsening of the chronic scores. Conclusion. IA IFX allowed for progression of refractory TMJ arthritis in most but not all children with JIA.

An Atypical Case of Chiari II Malformation Mimicking Partial Rhombencephalosynapsis.

Partial rhombencephalosynapsis in the presence of Chiari II malformation has been proposed as a “new abnormality of the hindbrain and spine“. We describe a case of Chiari II malformation with imaging features mimicking partial rhombencephalosynapsis. Our case demonstrates how the imaging findings of Chiari II malformation can be confused with the above entity and highlights the differentiating features to help radiologists make an accurate diagnosis.

Imaging of temporomandibular joint abnormalities in juvenile idiopathic arthritis with a focus on developing a magnetic resonance imaging protocol

Inflammation and damage in the temporomandibular joint (TMJ) often develop without clinical symptoms but can lead to severe facial growth abnormalities and impaired health-related quality of life, making early diagnosis of TMJ changes crucial to identify. Inflammatory and osteochondral changes detectable through magnetic resonance imaging (MRI) occur in TMJs of approximately 40% of children with juvenile idiopathic arthritis (JIA), and no other imaging modality or physical method of examination can reliably detect these changes. Therefore contrast-enhanced MRI is the diagnostic standard for diagnosis and interval monitoring of JIA. However the specific usage of MRI for TMJ arthritis is not standardized at present. There is a recognized need for a consensus effort toward standardization of an imaging protocol with required and optional sequences to improve detection of pathological changes and shorten study time. Such a consensus imaging protocol is important for providing maximum information with minimally necessary sequences in a way that allows inter-site comparison of results of clinical trials and improved clinical management. In this paper we describe the challenges of TMJ imaging and present expert-panel consensus suggestions for a standardized TMJ MRI protocol.

Intracranial blastomycosis mimicking high-grade neoplasm on magnetic resonance imaging and spectroscopy

We describe a case of posterior fossa blastomycosis in an immunocompetent patient that mimicked high-grade neoplasm on neuroimaging. Histological analysis confirmed blastomycosis. Because the neuroimaging characteristics of intracerebral blastomycosis can be confused for neoplasm, these lesions must be confirmed histologically before initiating aggressive treatment for presumptive high-grade neoplasm. To our knowledge, it is the first description of a neoplasm mimic on MRS in the setting of intracranial blastomycosis.

Progressive lung calcification after orthotopic heart transplant

Focal, asymmetrical pulmonary airspace opacities in post-transplant setting are commonly from infection, hemorrhage, edema or infarction. Rarely, stable or mildly progressive dense pulmonary opacities are due to pulmonary calcifications. In the majority of cases, these are asymptomatic and warrant no further intervention.