====== White Matter Disconnection ====== ===== 1. Definition ===== - **[[White matter]] [[disconnection]]** is the disruption of neural pathways linking different brain regions, caused by injury, disease, or surgery. ===== 2. Causes ===== ^ Cause ^ Examples ^ | **Trauma** | Diffuse axonal injury | | **Surgery** | Resection of brain tissue (e.g., epilepsy surgery) | | **Stroke** | Ischemic damage to white matter tracts | | **Tumors** | Compression or infiltration of tracts | | **Neurodegeneration** | Multiple sclerosis, Alzheimer's disease | ===== 3. Consequences ===== - **Memory impairment** (e.g., disconnection of hippocampal tracts). - **Language deficits** (e.g., arcuate fasciculus injury). - **Motor weakness** (e.g., corticospinal tract disruption). - **Executive dysfunction** (e.g., frontoparietal pathway damage). ===== 4. In Epilepsy Surgery ===== - Cognitive decline may occur due to injury to white matter pathways even when gray matter resection is limited. - Key affected tracts: * **[[Uncinate fasciculus]]** * **[[Inferior longitudinal fasciculus]]** * **[[Fornix]]** ===== 5. Assessment Techniques ===== ^ Method ^ Description ^ | **Diffusion Tensor Imaging (DTI)** | Maps white matter tracts via water diffusion | | **Tractography** | 3D reconstruction of pathways | | **Lesion-symptom mapping** | Correlation between injury site and clinical symptoms | ===== Summary ===== **White matter disconnection** disrupts brain network communication, leading to functional impairments. Preserving critical white matter tracts is essential in neurosurgery and neurorehabilitation.