Bilateral lesions of the basal ganglia and thalami (central grey matter)—pictorial review

Abstract

The basal ganglia and thalami are paired deep grey matter structures with extensive metabolic activity that renders them susceptible to injury by various diseases. Most pathological processes lead to bilateral lesions, which may be symmetric or asymmetric, frequently showing characteristic patterns on imaging studies. In this comprehensive pictorial review, the most common and/or typical genetic, acquired metabolic/toxic, infectious, inflammatory, vascular and neoplastic pathologies affecting the central grey matter are subdivided according to the preferential location of the lesions: in the basal ganglia, in the thalami or both. The characteristic imaging findings are described with emphasis on the differential diagnosis and clinical context.

Disseminated cryptococcal infection in a patient with a remote renal transplant

“… 6 Radiographic manifestations include meningoencephalitis, granulomas (cryprococcomas) and gelatinous pseudocysts, typically seen in the basal ganglia. 7 Differential diagnosis for basal ganglia lesions in immunocompromised patients includes cryptococcosis, as well as cerebral toxoplasmosis, viral encephalitis and malignant disease. 7 …”

“… 7 Differential diagnosis for basal ganglia lesions in immunocompromised patients includes cryptococcosis, as well as cerebral toxoplasmosis, viral encephalitis and malignant disease. 7 …”

“… 8 Calcineurin inhibitors, such as cyclosporine A and tacrolimus, are associated with lower 90-day mortality rates and increased long-term survival compared with azathioprine or MMF. 7 Calcineurin inhibitor–based immunosuppressive regimens are also associated with fewer central nervous infections than azathioprine or MMF-based regimens. 9 An increased risk of C. neoformans infection has been reported among patients receiving long-term steroids for autoimmune conditions; however, there is limited evidence linking the dose and duration of steroids and risk of cryptococcal infection among transplant recipients.…”

Cryptococcose disséminée chez une greffée rénale de longue date

“…Les autres symptômes courants comprennent une altération de l'état de conscience (environ 50 % des cas), des troubles visuels (environ 20 % des cas) et des convulsions ou des déficits neurologiques (< 10 % des cas), qui pourraient indiquer la présence d'une lésion occupant de l'espace, comme un cryptococcome 6 . Les examens radiographiques pourraient révéler la présence d'une méningoencéphalite, de granulomes (cryptococcomes) ou de pseudokystes gélatineux, souvent dans les noyaux gris centraux 7 . Le diagnostic différentiel des lésions des noyaux gris centraux chez les patients immunodéficients comprend la cryptococcose, la toxoplasmose cérébrale, l'encéphalite virale et les affections malignes 7 .…”

Scientific publishing during the COVID-19 pandemic

“…We were happy to publish "COVID-19: A primer for Neuroradiologists" in April [1]. August followed with a pictoral review of "Bilateral lesions of the basal ganglia and thalami (central grey matter)" that included COVID-19-associated acute necrotizing encephalopathy [2]. Although Neuroradiology publishes only exceptional case reports, we presented in September a patient with "COVID-19-induced anosmia associated with olfactory bulb atrophy," who had a pre-COVID MRI for comparison [3].…”