′Hot-cross bun′ and ′inverse trident sign′ in progressive multifocal leukoencephalopathy with HIV seropositivity

HIV-Associated JC Virus-Granule-Cell Neuronopathy (JCV-GCN) with the Hot-Cross-Bun Sign

“…Whether HCB occurs from onset or is a feature of later JCV-GCN stages is discussed. Our patient's long radiological monitoring supports the latter hypothesis, as previously suggested [10]. GCs are a major class of cerebellar interneurons in synaptic contact with Purkinje cells.…”

“…JCV-GCN is sometimes associated with T2-weighted/fluid-attenuated inversion recovery (FLAIR) hyperintense white matter abnormalities typical of PML but is a distinct clinical entity [1]. Only 24 cases of HIVassociated JCV-GCN, including our patient, have been reported [9][10][11][12][13][14][15][16].…”

“…The MRI HCB sign, characterized by cruciform T2-and FLAIRsignal hyperintensity within the pons (Figure 1), has been described in only 6 HIV-associated JCV-GCN patients [9,10,15,16]. It is said to be highly specific, but not pathognomonic, for multiple-system atrophy (MSA).…”

Paraneoplastic neurological syndrome due to burned-out testicular tumor showing hot cross-bun sign

“…Hot cross-bun sign is seen on transverse T2-weighted MRI of the brain as a cruciform hyperintensity in the pons (14). It is frequently seen in cerebellar type of multiple system atrophy (MSA) and spinocerebellar ataxia, and rarely reported in the cases with variant Creutzfeld-Jakob disease, secondary parkinsonism, cerebrotendinous xanthomatosis, progressive multifocal leukoencephalopathy in HIV seropositive (15) and bilateral pontine infarction (16). The hot cross-bun sign is recently considered not a pathognomonic sign for the diagnosis of MSA but just reflecting degeneration of pontine neurons and transverse pontocerebellar fibers in various types of olivopontocerebellar atrophy irrespective of the underlying pathogenic process (17).…”

Medullary Hot-Cross Bun Sign in Multiple System Atrophy-Cerebellar

“…Pontine HCB sign is neither always seen nor a pathognomonic in MSA patients. It is also seen in spinocerebellar ataxia, cerebrotendinous xanthomatosis [4], parkinsonism secondary to vasculitis [5], human immunodeficiency virus [6], and variant Creutzfeldt-Jakob disease [7].…”