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.

Neurodegeneration with brain iron accumulation (NBIA) is etiologically, clinically, and by imaging a heterogeneous group including NBIA types 1 [pantothenate kinase-associated neurodegeneration (PKAN)] and 2 (PLA2G6-associated neurodegeneration), neuroferritinopathy, and aceruloplasminaemia. Data on genetically defined Indian-subcontinent NBIA cases are limited. We report 6 patients from the Indian-subcontinent with a movement disorder and MRI basal ganglia iron deposition, compatible with diagnosis of an NBIA syndrome. All patients were screened for abnormalities in serum ceruloplasmin and ferritin levels and mutations in NBIA-associated genes [pantothenate kinase 2 (PANK2), PLA2G6 and ferritin light chain (exon 4)]. We present clinical, imaging and genetic data correlating phenotype-genotype relations. Four patients carried PANK2 mutations, two of these were novel. The clinical phenotype was mainly dystonic with generalized dystonia and marked orobulbar features in the 4 adolescent-onset cases. One of the four had a late-onset (age 37) unilateral jerky postural tremor. His mutation, c.1379C>T, appears associated with a milder phenotype. Interestingly, he developed the eye-of-the-tiger sign only 10 years after onset. Two of the six presented with adult-onset levodopa (L-dopa)-responsive asymmetric re-emergent rest tremor, developing L-dopa-induced dyskinesias, and good benefit to deep brain stimulation (in one), thus resembling Parkinson's disease (PD). Both had an eye-of-the-tiger sign on MRI but were negative for known NBIA-associated genes, suggesting the existence of further genetic or sporadic forms of NBIA syndromes. In conclusion, genetically determined NBIA cases from the Indian subcontinent suggest presence of unusual phenotypes of PANK2 and novel mutations. The phenotype of NBIA of unknown cause includes a PD-like presentation.

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.

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.

We report a case of posterior atlantoaxial dislocation without a fracture of the odontoid in a 35-year-old woman. There have been nine reported cases of similar injury in the English literature. The integrity of the transverse ligament following posterior atlantoaxial dislocations has not been well documented in these reports. In the present case, MRI revealed an intact transverse ligament, which probably contributed to the stability of the C1-C2 complex following closed reduction.

A 61-year-old female patient presented with diffuse pain in the dorsal region of the back of 3 months duration. The magnetic resonance imaging showed an extramedullary, extradural space occupative lesion on the right side of the spinal canal from D5 to D7 vertebral levels. The mass was well marginated and there was no bone involvement. Compression of the adjacent thecal sac was observed, with displacement to the left side. Radiological differential diagnosis included nerve sheath tumor and meningioma. The patient underwent D6 hemilaminectomy under general anesthesia. Intraoperatively, the tumor was purely extradural in location with mild extension into the right foramina. No attachment to the nerves or dura was found. Total excision of the extradural compressing mass was possible as there were preserved planes all around. Histopathology revealed cavernous hemangioma. As illustrated in our case, purely epidural hemangiomas, although uncommon, ought to be considered in the differential diagnosis of spinal epidural soft tissue masses. Findings that may help to differentiate this lesion from the ubiquitous disk prolapse, more common meningiomas and nerve sheath tumors are its ovoid shape, uniform T2 hyperintense signal and lack of anatomic connection with the neighboring intervertebral disk or the exiting nerve root. Entirely extradural lesions with no bone involvement are rare and represent about 12% of all intraspinal hemangiomas.

Objectives: This is a retrospective institutional review of clinical data and radiological findings of cerebral malaria patients presenting to a tertiary centre in India, which is an known to be endemic for malarial disease. Methods: The present series describes MRI in four cases all of which revealed bithalamic infarctions with or without haemorrhages in patients with cerebral malaria, and this review examines a subset of patients with this condition. In addition, acute haemorrhagic infarctions were also seen the in brain stem, cerebellum, cerebral white matter and insular cortex in two of the four patients. Results: In this series, the patient with cerebellum and brain stem involvement died. The remaining three survived with antimalarial and supportive treatment. No neurological symptoms were noted on clinical follow-up. MRI follow-up was obtained in only one of the three patients (3 months post-treatment) and showed resolution of thalamic infarctions. Conclusion: These imaging features may help in the early diagnosis of cerebral malaria so that early treatment can begin and improve the clinical outcome.

A subset of diabetic COVID-19 patients treated with steroids, oxygen, and/or prolonged intensive care admission develop rhino-orbito-cerebral mucormycosis. Radiologists must have a high index of suspicion for early diagnosis, which prompts immediate institution of antifungal therapy that limits morbidity and mortality. Assessment of disease extent by imaging is crucial for planning surgical debridement. Complete debridement of necrotic tissue improves survival. Imaging features reflect the angioinvasive behaviour of fungal hyphae from the Mucoraceae family, which cause necrotising vasculitis and thrombosis resulting in extensive tissue infarction. Contrast-enhanced magnetic resonance imaging (MRI) is the imaging technique of choice. The classic “black turbinate” on contrast-enhanced imaging represents localised invasive fungal rhinosinusitis (IFRS). A striking radiological feature of disseminated craniofacial disease is non-enhancing devitalised and necrotic soft tissue at the orbits and central skull base. Sinonasal and extrasinonasal non-enhancing lesions in IFRS are secondary to coagulative necrosis induced by fungal elements. Multicompartmental and extrasinonasal tissue infarction is possible without overt bone involvement and caused by the propensity of fungal elements to disseminate from the nasal cavity via perineural and perivascular routes. Fungal vasculitis can result in internal carotid artery occlusion and cerebral infarction. Remnant non-enhancing lesions after surgical debridement portend a poor prognosis. Assessment for the non-enhancing MRI lesion is crucial, as it is a sole independent prognostic factor for IFRS-specific mortality. In this review, we describe common and uncommon imaging presentations of biopsy-proven rhino-orbito-cerebral mucormycosis in a cohort of nearly 40 COVID-19 patients.