Radiological Imaging of the Lacrimal Gland in Sjogren's Syndrome: A Systematic Review and Meta-Analysis.

PURPOSE: To critically appraise the evidence on the ability of the lacrimal gland ultrasonography (USG) or magnetic resonance imaging (MRI) to differentiate between Sjogren's syndrome and non-Sjogren's syndrome/healthy controls. METHODS: A systematic review and meta-analysis (based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines) of online literature search was performed using PubMed, Scopus, and Cochrane databases. Cohort studies comparing the imaging features of the lacrimal glands of Sjogren's syndrome with a control group were included. Quantitative synthesis was performed using the RevMan (Version 5.4.1). RESULTS: Six studies used USG as an imaging technique, and three used MRI for the lacrimal gland imaging. The lacrimal gland affected with Sjogren's syndrome shows glandular heterogeneity on USG and MRI. Heterogeneity on USG had 6.18 times higher odds of the lacrimal gland being involved with Sjogren's syndrome (95% CI, 3.31-11.55). Gland hyperechogenicity cannot reliably differentiate the glandular involvement in Sjogren's syndrome. There is insufficient data for analysis on the gland size, hypoechoic areas, fibrous bands, and increased lacrimal artery resistance in Sjogren's syndrome patients. Of the three MRI-based studies, reduced apparent diffusion coefficient and heterogeneity were the characteristics of Sjogren's syndrome. Clinical parameters such as dry eye symptomatology and Schirmer values had variable associations with USG or MRI parameters. Ultrasonography parameters were no different between dry eye versus no dry eye in Sjogren's syndrome patients, whereas small-sized glands had low Schirmer on MRI-based studies. CONCLUSION: Glandular heterogeneity on USG is significantly associated with lacrimal gland involvement in Sjogren's syndrome patients. However, the role of radiology in predicting lacrimal gland involvement is unclear as the evidence is insufficient and heterogeneous.

Cryptogenic posterior circulation stroke in children.

We aimed to evaluate the percentage of posterior circulation arterial ischaemic stroke (PCAIS) caused by craniovertebral junction (CVJ) anomalies and describe their clinical course. Children admitted to a tertiary care paediatric hospital with PCAIS between July 2017 and December 2020 were assessed retrospectively for disease aetiology. We reviewed the clinical, radiological, and surgical details of children with evidence of CVJ anomalies. Fourteen (24.1%) of 58 children admitted with arterial ischaemic stroke had posterior circulation involvement. The mean age of patients presenting with posterior circulation stroke was 6 years 6 months (range 3 months-15 years), 11 were male. Six of 14 cases with PCAIS were due to CVJ anomaly, their ages ranged from 4 months to 15 years (two age ranges were noted, 4 months-4 years and 11-15 years), four were male. Two children had atlantoaxial dislocation with basilar invagination, two had Bow Hunter syndrome with Chiari malformation type 1 (one with completed stroke), one had Chiari malformation type 1 alone, and one presented with Farber disease with proatlas segmentation anomaly in CVJ. The time lag to stroke and CVJ diagnosis ranged from 2 weeks to 24 months. A dynamic angiogram was required to evaluate biomechanical changes on scans with inconclusive findings on standard stroke imaging. CVJ anomalies are an important treatable cause of paediatric posterior circulation stroke. Cervical spine x-ray in flexion and extension should be done in all patients with posterior circulation stroke beyond the acute period. In cryptogenic aetiology, provocative angiography with guarded neck rotation should be considered to evaluate possible dynamic vertebral artery compression. WHAT THIS PAPER ADDS: Craniovertebral junction anomalies are an important cause of posterior circulation stroke in children. Evidence of flat occiput, short neck, and short stature in children with posterior circulation stroke should be assessed. Dynamic imaging helps identify dynamic vertebral artery compression.

Magnetic resonance imaging in rhino-orbital-cerebral mucormycosis.

Coronavirus disease-associated mucormycosis (CAM) is an established clinical entity in India. In the past 4 months, there has been a sharp upsurge in the number of CAM cases in most parts of the country. Early diagnosis can be lifesaving. Magnetic resonance imaging (MRI) imaging remains the corner stone of management in patients with ROCM. This review discussed the utility of MRI imaging in ROCM with an emphasis on the ideal MRI protocol in a suspected case of ROCM, the pathways of spread of infection, the classic diagnostic features, MRI for staging of the disease, MRI for prognostication, MRI for follow up, and imaging features of common differentials in ROCM. The pit falls of MRI imaging and a comparison of CT and MRI imaging in ROCM are discussed. The clinical interpretation of areas of contrast uptake and those of necrosis and its relevance to treatment are discussed. This review aims to familiarize every member of the multidisciplinary team involved in managing these patients to be able to interpret the findings on MRI in ROCM.

Managing DICOM images: Tips and tricks for the radiologist.

All modalities in radiology practice have become digital, and therefore deal with DICOM images. Image files that are compliant with part 10 of the DICOM standard are generally referred to as "DICOM format files" or simply "DICOM files" and are represented as ".dcm." DICOM differs from other image formats in that it groups information into data sets. A DICOM file consists of a header and image data sets packed into a single file. The information within the header is organized as a constant and standardized series of tags. By extracting data from these tags one can access important information regarding the patient demographics, study parameters, etc. In the interest of patient confidentiality, all information that can be used to identify the patient should be removed before DICOM images are transmitted over a network for educational or other purposes. In addition to the DICOM format, the radiologist routinely encounters images of several file formats such as JPEG, TIFF, GIF, and PNG. Each format has its own unique advantages and disadvantages, which must be taken into consideration when images are archived, used in teaching files, or submitted for publication. Knowledge about these formats and their attributes, such as image resolution, image compression, and image metadata, helps the radiologist in optimizing the archival, organization, and display of images. This article aims to increase the awareness among radiologists regarding DICOM and other image file formats encountered in clinical practice. It also suggests several tips and tricks that can be used by the radiologist so that the digital potential of these images can be fully utilized for maximization of workflow in the radiology practice.

Case Report: Magnetic resonance imaging in rabies encephalitis.

Rabies encephalitis is an invariably fatal disease characterized by typical clinical symptoms. Although the diagnosis of this condition can be made on the basis of the patient's history and the classical clinical presentation, neuroimaging may still play a role, especially for establishing an early diagnosis in cases with atypical presentations or when the history of animal bite is not forthcoming. We report the MRI findings in a case of furious rabies encephalitis and describe the utility of diffusion imaging in its diagnosis.

Evaluation, management, and long-term follow up of vein of Galen malformations.

OBJECT: Vein of Galen malformations (VGMs) are extremely rare intracranial lesions. Clinical presentation and management strategies vary significantly in different areas of the world. The authors report their experience in evaluation, management, and long-term follow up of these lesions in India. METHODS: Between October 1983 and June 2003, 25 patients with VGMs were referred to the authors' institution for evaluation and management. Ten children younger than 2 years of age presented with rapidly increasing head size as the chief complaint. Among 11 children 2 years of age or older, the most common presenting symptom was chronic headache. Four patients who presented during adulthood had chronic headache for many years before presentation. Angiographic evaluation of the lesion was performed in 21 patients. Fifteen patients were treated using endovascular techniques. Injection of the embolic material was performed after induction of systemic hypotension when the flow in the fistula was high. Complete occlusion of the arteriovenous shunt could be achieved in two patients with vein of Galen aneurysmal dilation (100% of patients with this type of malformation) and in five of the six patients with the mural type of malformation (83%). Among patients with the choroidal type of malformation, complete obliteration of the shunt could be achieved in three patients. In three patients with high-flow choroidal malformations, embolization carried out in a single sitting resulted in shunt reduction of nearly 90%. These patients received clinical follow up. CONCLUSIONS: The authors' experience in evaluation and management of VGMs reveals that in areas of the world where access to dedicated specialist care is limited, the clinical presentation of VGMs can differ appreciably from the classic descriptions in the literature. Endovascular management of these lesions results in excellent angiographic and clinical results.