Cases

Lubdha M. Shah, MD

CASE 1

Right Parietal Opercular Cavernous Malformation (CM)

Tongue-tapping task demonstrates that lateral primary motor cortex abuts CM and may be vulnerable to injury during surgical resection
Language tasks, including word generation and passive listening, confirm left dominant language
- As CM lies in contralateral hemisphere to dominant language areas, little risk of language pathway disruption

CASE 2

Primary Motor Cortex Relative to Intraaxial Lesion

Case 2A: Intraaxial lesion in left superior parietal lobe involves left postcentral gyrus and abuts precentral gyrus
- Right thumb-tapping task confirms primary motor cortex immediately adjacent to anterior margin of lesion; helps in planning surgical approach
Case 2B: Oligodendroglioma in left superior frontal gyrus extends posteriorly to expected region of primary motor cortex
- Right foot-flexing task demonstrates activation in parasagittal right foot motor area, which abuts posterior margin of lesion
- Supplementary motor area (SMA) touches medial aspect of lesion
  - Injury to SMA may result in postop motor deficit, which often improves or resolves

CASE 3

Extensive Right Temporoparietal Glioblastoma Multiforme

MPRAGE images with DTI color fractional anisotropy data overlay demonstrate medial deviation of corticospinal tracts and superior longitudinal fasciculus
fMRI shows anterior displacement of tongue motor area
Language tasks confirm left-dominant language areas

CASE 4

Language Involvement by Left Insular Mass: Crossed Dominance

Slow-growing lesions involving classic language areas may result in crossed dominance
- Dominant right-expressive speech with small left-expressive speech component
- Dominant left-receptive speech in posterior superior temporal gyrus within 1 cm of posterior margin of lesion
Lesion likely involves arcuate fasciculus
- Subtotal surgical resection to preserve speech

CASE 5

Atypical Language

May be cortical reorganization due to encephalomalacia, infarction, tumor, vascular malformation
- Atypical/right hemisphere language dominance in early cortical injury during language formative period
Language laterality may be split
Studies show cortical reorganization patterns and functional recovery after stroke affected by corticospinal tracts, brainstem pathways, and interhemispheric connections

CASE 6

Case-Specific Language Paradigms

Case 6A: Language activation can be elicited using American Sign Language via video
Case 6B: Language tasks can be administered in a subject’s native language &/or in English if the subject is fluent

CASE 7

Decreased Visual Cortical Activation

Different visual tasks can be used to define retinotopic map for subject
- Presurgical visual field mapping for occipital lobe lesions
- Confirming visual field defects from retinal or optic pathway lesions

CASE 8

Mapping of Semantic Memory Regions

Activation in bilateral hippocampus and parahippocampal gyri
- Typically bilateral activation that does not predict memory impairment after hippocampal resection
- Wada correlation may be helpful

CASE 9

Intraparietal Sulci and Frontal Eye Fields

fMRI paradigms include following cursor, complex patterns, arithmetic problems
Activates attention control network
Presurgical mapping of frontal eye fields for superior frontal lobe lesions
- Deficits improve over weeks after injury, but can have permanent injury to saccadic eye movements

CASE 10

Arteriovenous Malformation (AVM)

Cortical reorganization with AVM overlying eloquent areas suggests that AVM resection may be possible with acceptable facial motor neurological deficits

CASE 11

AVM-Neurovascular Uncoupling