Malignant brachial plexopathy: A pictorial essay of MRI findings.

For imaging, the brachial plexus is a technically and anatomically challenging region of the peripheral nervous system. MRI has a central role in the identification and accurate characterization of malignant lesions arising here, as also in defining their extent and the status of the adjacent structures. The purpose of this pictorial essay is to describe the MRI features of primary and secondary malignant brachial plexopathies and radiation-induced brachial nerve damage.

Imaging features of extraaxial musculoskeletal tuberculosis.

Tuberculosis (TB) continues to be a public health problem in both developing and industrialized countries. TB can involve pulmonary as well as extrapulmonary sites. The musculoskeletal system is involved in 1-3% of patients with tuberculosis. Although musculoskeletal TB has become uncommon in the Western world, it remains a huge problem in Asia, Africa, and many developing countries. Tuberculous spondylitis is the most common form of musculoskeletal TB and accounts for approximately 50% of cases. Extraspinal musculoskeletal TB shows a predilection for large joints (hip and knee) and para-articular areas; isolated soft tissue TB is extremely rare. Early diagnosis and prompt treatment are mandatory to prevent serious destruction of joints and skeletal deformity. However, due to the nonspecific and often indolent clinical presentation, the diagnosis may be delayed. Radiological assessment is often the first step in the diagnostic workup of patients with musculoskeletal TB and further investigations are decided by the findings on radiography. Both the radiologist and the clinician should be aware of the possibility of this diagnosis. In this manuscript we review the imaging features of extraspinal bone, joint, and soft tissue TB.

Bilateral anterior cerebral artery infarction following viper bite.

The viper is one of India's most commonly encountered poisonous snakes and envenomation following viper bite usually leads to consumption coagulopathy. Clinical manifestations most frequently include external and internal bleeding. In the setting of viper envenomation, large-vessel thrombosis is a very rare occurrence. Also, bilateral anterior cerebral artery infarction, when unrelated to anatomical abnormalities, subarachnoid haemorrhage, surgery or trauma, itself is an exceedingly rare event. We report a case of a 24-year-old previously healthy man who presented with bilateral anterior cerebral artery infarction following a viper bite. We also present hypotheses that may explain this unusual occurrence.

Pancreatic tuberculosis: a clinical and imaging review of 32 cases.

BACKGROUND: Tuberculosis of the pancreas is a rare entity, and anecdotal reports describing imaging features of pancreatic tuberculosis have been described in medical literature. The imaging features including computed tomography (CT) and ultrasonography in diagnosed cases of tubercular involvement of the pancreas are described, with an overview of clinical features and laboratory investigations. MATERIALS AND METHODS: We analyzed records of 384 patients of diagnosed cases of abdominal tuberculosis for involvement of pancreas and detected 32 patients (8.33%) who had pancreatic involvement. This included 22 men and 10 women with an age range of 19 to 64 years (mean age of 42.5 years), who were detected to have pancreatic tuberculosis from 1999 to 2004 in our institute. We reviewed the clinical, radiologic (ultrasonographic and CT features), and laboratory findings of all patients. The criteria for diagnosis of tuberculosis were based on ascitic fluid adenosine deaminase level in 14 patients, fine-needle aspiration cytology of lymph nodes in 9 patients, and presence of pulmonary tuberculosis on chest radiograph, which was found in 9 patients. On follow-up, 6 months after antituberculous treatment, 25 patients showed response to anti-Koch's treatment, 3 patients had drug-resistant tuberculosis, 2 patients died, and 2 patients were lost to follow-up. RESULTS: The male/female ratio was 2.2:1. The maximum number of patients was in the fourth decade (30-39 years). The duration of symptoms was spanning between 2 and 11 months, with a mean duration of 6 months. The most common symptom was abdominal pain localized to the epigastrium. Sixteen patients were seropositive for HIV-1 infection. Fourteen patients had history of tuberculosis of the lungs, whereas 18 patients had pancreatic and peripancreatic involvement as the primary manifestation. Ultrasonography showed bulky inhomogenous pancreas in 5 patients; solitary or multiple hypoechoic collections were observed in all 7 and 20 patients, respectively. CT findings demonstrated hypodense collections within the pancreas associated with peripancreatic lymphadenopathy in 29 patients. Three patients had a complex pancreatic mass lesion. CONCLUSIONS: Pancreatic tuberculosis can present with a variable spectrum of imaging findings. Tuberculosis of the pancreas should be considered as a diagnostic possibility in patients who present with a pancreatic space occupying lesion associated with peripancreatic lymphadenopathy.

MRI features of tuberculosis of the knee.

OBJECTIVE: The objective of this study was to describe the magnetic resonance imaging (MRI) features of tuberculosis (TB) of the knee joint. MATERIALS AND METHODS: The MRI features in 15 patients with TB of the knee, as confirmed by histology of the biopsied joint synovium, were reviewed retrospectively. The images were assessed for intra-articular and peri-articular abnormalities. RESULTS: All patients had florid synovial proliferation. The proliferating synovium showed intermediate to low T2 signal intensity. In the patients who were administered intravenous contrast, the hypertrophic synovium was intensely enhancing. Marrow edema (n = 9), osteomyelitis (n = 4), cortical erosions (n = 5), myositis (n = 6), cellulitis (n = 2), abscesses (n = 3), and skin ulceration/sinus formation (n = 2) were seen in the adjacent bone and soft tissue. CONCLUSION: Synovial proliferation associated with tuberculous arthritis is typically hypointense on T2-weighted images. This appearance, in conjunction with other peri-articular MRI features described, can help in distinguishing TB arthritis from other proliferating synovial arthropathies.

Colloid cyst of the velum interpositum: a common lesion at an uncommon site.

BACKGROUND: Colloid cysts are typically located in the region of the anterior third ventricle in the proximity of foramen of Monro. Although 'endodermal cyst' has been identified in several regions of the brain, location of characteristic colloid cyst entirely within the confines of velum interpositum and outside the ventricles has not been reported earlier. CASE DESCRIPTION: We report a unique case of colloid cyst located in the region of velum interpositum in a 33-year-old patient with headache and seizures. Such a location of the colloid cyst has not been identified earlier in the literature. The literature on pathogenesis of colloid cysts in general is briefly reviewed. CONCLUSIONS: Colloid cyst located in the velum interpositum is reported. Such a location gives additional information on the pathogenesis of these lesions.

Three distinct co-existent primary brain tumors in a patient.

A rare case of simultaneous occurrence of three entirely distinct intracranial tumors is described. A 55-year-old male with no evidence of phacomatoses or history of radiation therapy presented with complaints of increased drowsiness, headaches, and dysarthria. Investigations revealed an olfactory groove meningioma, a glioblastoma multiforme in the left medial temporal lobe, and a diffuse glioma in the brain stem. Occurrence of multiple varieties of tumors at the same time is extremely rare. Theories that explain their occurrences including the role of common carcinogens, autocrine growth factors, and tumor suppressor genes are discussed.

Acute calcific retropharyngeal tendinitis.

Knowledge of the characteristic clinical spectrum and imaging features of this disorder are crucial for a correct diagnosis of this uncommon cause of odynophagia and dysphagia.