Table 1.
Comparative characteristics of tumoral and pseudotumoral lesions in the differential diagnosis of HIV-associated CNS pathologies.
| mpMRI features | Tumor-like lesions | Tumors | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Neurotoxoplasmosis/Aspergillosis | Cryptococcosis | CNS-tuberculosis | TDL | PML | Cerebral infarction | Glioblastoma | PCNSL | Atypical PCNSL | |
| Preferential location | Variable | Basal ganglia, thalamus, and midbrain; basal cisterns (meningitis) | Basal ganglia (tuberculoma); basal cisterns (meningitis) | Supratentorial | Periventricular and subcortical with involving U-fibers | Corresponds to the affected vascular territories | Predominantly supratentorial | Periventricular and subpial | Periventricular and subpial |
| Type of lesion | Multiple, rarely solitary | Multiple, rarely large solitary | Multiple | Usually, a solitary large one | Multiple, asymmetric | Solitary or multiple | Solitary, less often multiple (multifocal/multicentric) | Usually solitary | Solitary or multiple |
| Edema | Moderate vasogenic | Absent; moderate vasogenic (cryptococcoma) | Mild vasogenic | Moderate vasogenic or absent | Absent | Cytotoxic | Severe vasogenic | Moderate vasogenic | Moderate vasogenic |
| Contrast enhancement (CE) on T1-W | Nodular or ring CE | Variable, often no CE (cryptococcoma); lepto-pachymeningeal CE (meningitis) | Ring-shaped (tuberculoma and abscess) and homogenous (tuberculoma); lepto-pachymeningeal CE (meningitis) | Open-ring CE | Absent, rarely patchy or punctate CE at the lesion border in IRIS | Gyral CE, rarely ring CE | Ring CE | Homogenic vivid CE | Homogenic vivid CE, sometimes ring CE |
| Hemorrhage | Typical for fungal etiology | Absent | Absent | Not typical | Not typical | Present in cases of hemorrhagic transformation | Always present | Absent | Sometimes occur |
| DWI/ADC | Restricted in the wall | Variable (cryptococcoma); significant restricted in infarcts | Significant restricted in abscess cavity and infarcts | Restricted on the periphery, facilitated in the center | Restricted at the lesion border | Significant restricted | Restricted in the solid component | Significant restricted | Significant restricted |
| DSC/ASL | Low | Low | Low | Variable, usually low | High at the lesion border | Low | Always high | Low | Often high |