This document discusses the common neurological manifestations seen in patients with HIV/AIDS and their appearance on radiological imaging. It describes HIV encephalitis as the most frequent manifestation, appearing as diffuse symmetric white matter hyperintensities. Toxoplasmosis typically appears as multifocal lesions over 2-3cm with peripheral enhancement. Cryptococcal meningitis can cause leptomeningeal or parenchymal lesions. Progressive multifocal leukoencephalopathy lesions are non-enhancing. Cytomegalovirus commonly involves the periventricular regions. Primary CNS lymphoma often appears as enhancing lesions that cross the corpus callosum. Tuberculosis can cause tuberculomas with peripheral enhancement.

1. Radiology of Neurological
Manifestations of HIV
Dr. Rahi kiran.B
SR Neurology
GMC, KOTA

3. HIV Encephalitis
• 60% of AIDS patients develop neurologic disease
• HIV encephalitis (HIVE) and HIV leukoencephalopathy (HIVL)-
direct result of HIV infection of the brain.
• HIV-associated neurocognitive disorders (HANDs) - most frequent
neurologic manifestations of HIVE and HIVL.
• The term "acquired immunodeficiency dementia complex” refers
specifically to HIV-associated dementia.

4. HIV Encephalitis

5. HIV Encephalitis
Diffuse,confluent, bilaterally symmetric hyperintensity in the cerebral white matter with
sparing of the subcortical U-fibers, no parenchymal or meningeal enhancement, Axial DWI
shows no evidence of restricted diffusion

6. Toxoplasma
• most commonly involves the basal ganglia, thalami, CMJ and
cerebellum
• Multifocal lesions > solitary
• average SIZE 2-3 cm in diameter.

7. Toxoplasma
NECT – hypodense in left BG and frontal lobe with marked peripheral edema.T2WI- three
separate heterogeneous masses surrounded by marked edema, T1 C+ -eccentric "target" sign
lesion with a peripheral rim of enhancement

8. Cryptococcosis
Meningeal disease
• T1 C+ (Gd): can show
leptomeningeal enhancement
Cryptococcomas
• variable density masses on CT
• T1: low signal
• T2 / FLAIR: high signal
• T1 C+ (Gd): variable, ranging from
no enhancement to peripheral
nodular enhancement(depends on
immunity as capsule is non-
immunogenic)
• No DWI

9. • Immunocompetent - more likely to present with
cryptococcomas.
• Enhancement of these lesions might occur as a result of an
immunologic reaction by the host.
• Immediate and delayed imaging with a double dose of
contrast has been reported to reduce the false negative
studies by showing meningeal enhancement in
immunocompromised patients.

10. • Axial T1 post-gadolinium
image shows typical
cryptococcal meningitis
with ventricular wall
enhancement and subtle
frontal and occipital
leptomeningeal
enhancement.

11. Gelatinous pseudocysts
• Tend to give a "soap bubble"
appearance.
• low-density lesions on CT
• T1: low to intermediate (from mucin)
signal , no T1C+ (avascular)
• T2: hypointense ring surrounding a
hyperintense center
• FLAIR: low signal
• DWI - may or may not
• Hydrocephalus is the most common,
although nonspecific finding.

12. Progressive Multifocal
Leukoencephalopathy

13. c Progressive Multifocal
Leukoencephalopathy
clinically deteriorating 46y HIV-positive patient with a CD4 count < 10 cells/μL
confluent assymetric nonenhancing left occipital lesion that crosses the corpus
callosum

14. iPML
T1 & T2 -Characteristic involvement of both MCP, T1 C+ very faint rim enhancement, the right
MCP lesion restricts strongly

15. Cytomegalovirus
periventricular ependymal enhancement-
ventriculitis
periventricular restricted diffusion.

16. PCNSL
• 2-6% of HIV patients.
• 70% of all solitary brain parenchymal lesions in HIV/AIDS
patients.
• 90% are supratentorial - BG and deep white matter
• cross the corpus callosum
• highly specific - Linear enhancement at the margins of a
lesion, tracking along Virchow-Robin spaces

17. PCNSL
hypointense nodular
lesions on axial T2
Nodular enhancement
accompanied by linear
enhancement at the
margins of a lesion,
tracking along
perivascular spaces
restricted diffusion

18. PCNSL vs Toxoplasma
PCNSL
• single lesion
• subependymal spread
• solid enhancement
• no hemorrhage before
treatment
• thallium SPECT positive
• MRS: increased choline
• MR perfusion: increased
rCBV
Toxoplasma
• multiple lesions
• basal ganglia and CMJ
• ring or nodular enhancement
• hemorrhage occasionally occurs
mostly in the periphery
• thallium SPECT negative
• MRS: decreased choline
• MR perfusion: decreased rCBV

19. Tuberculosis
Hypointense center surrounded by hyperintense capsule that
enhances peripherally on contrast
meningeal enhancement in
the basal cisterns and
hydrocephalus

20. HIV-Associated Vacuolar
Myelopathy
• slowly progressive, painless spastic
paraparesis with sensory loss,
imbalance, and sphincter dysfunction.
Relapsing-remitting courses have been
described.
High-intensity lesion in the C2-C5
posterior spinal cord

22. Toxoplasma
T1 C+ -eccentric "target" sign
lesion with a peripheral rim of
enhancement
Large, heterogeneously hyperintense lesions but
numerous smaller foci scattered throughout the brain
in the cortex, BG and subcortical white matter
A 45-year-old male with CD4+ < count 100/mL, hemiparesis, and GTCS

23. Multiple gelatinous
pseudocysts and HIVE
Multiple pseudocysts and hyperintensity in the
cerebral white matter

24. PML-IRIS
Baseline MRI Repeat MRI 5 weeks after deterioration
Bifrontal hyperintense subcortical non-
enhancing white matter lesions
New lesions and enhancing
A 55-year-old female with, hemiparesis and GTCS-started on ART

25. Cytomegalovirus
periventricular ependymal enhancement-
ventriculitis
periventricular restricted diffusion.
A 35-year-old male with CD4+ < count 50/mL and GTCS

26. HIV Encephalitis
Diffuse,confluent, bilaterally symmetric hyperintensity in the cerebral white matter with
sparing of the subcortical U-fibers, no parenchymal or meningeal enhancement, Axial DWI
shows no evidence of restricted diffusion
A 32 yr female with cognitive, behavioral and motor dysfunction

27. PCNSL
hypointense nodular
lesions on axial T2
Nodular enhancement
accompanied by linear
enhancement at the
margins of a lesion,
tracking along
perivascular spaces
restricted diffusion
A 54-year-old male with left-sided weakness

28. toxoplasma abscess
"Eccentric target sign“, less prominent
choline peak and reduced NAA, large
lipid lactate peak
51-year-old male,
known HIV sero-
positive, initially
asymptomatic, came
with complaints of
generalized weakness
since 2 months
lymphoma vs
toxoplasma abscess

29. Tuberculosis
Hypointense center surrounded by hyperintense capsule that
enhances peripherally on contrast
meningeal enhancement in
the basal cisterns and
hydrocephalus
A 34-year-old male with seizures

30. THANK YOU