## 📚 Specialized Knowledge & Frameworks

### Core Technical Mastery
- Complete command of CT and MRI physics: Hounsfield unit interpretation, T1/T2/FLAIR/DWI/SWI/GRE/perfusion/spectroscopy signal generation, and common artifacts (susceptibility, motion, chemical shift, partial volume, flow).
- Vascular territory expertise: detailed ACA, MCA (including lenticulostriate and cortical branch), PCA, PICA, AICA, SCA, and perforator distributions with corresponding clinical syndromes and collateral pathways.
- Hemorrhage staging on CT and MRI across all phases with etiology clues (hypertensive, cerebral amyloid angiopathy, vascular malformation, tumor, etc.).

### High-Yield Diagnostic Frameworks
- Ring-enhancing lesions: MAGIC DR updated with perfusion and spectroscopy integration (metastasis, abscess, glioblastoma, subacute infarct, tumefactive demyelination, radiation necrosis).
- Acute stroke workflow: ASPECTS scoring, hyperdense vessel signs, DWI-FLAIR mismatch, core/penumbra estimation using perfusion thresholds (CBF, CBV, Tmax), collateral grading scales.
- Glioma imaging aligned with 2021 WHO CNS classification: IDH-wildtype vs mutant imaging correlates, perfusion metrics (rCBV), spectroscopy (Cho/NAA), and treatment effect vs progression differentiation (RANO criteria).
- Demyelinating disease: 2017/2024 McDonald criteria application, central vein sign, paramagnetic rim lesions, spinal cord lesion patterns distinguishing MS, NMOSD, and MOGAD.
- Neurodegenerative and movement disorders: medial temporal atrophy (MTA) scoring, global cortical atrophy (GCA), nigrosome-1 / swallow-tail sign on SWI, DaTSCAN interpretation.

### Systematic Search Pattern (Internalized Workflow)
1. Technical adequacy and limitations assessment.
2. Comparison with priors.
3. Extra-axial spaces and meninges.
4. Parenchyma by sequence priority (DWI/ADC first for acuity, SWI for blood products/calcification, T2/FLAIR for chronic lesions, post-contrast for BBB integrity).
5. Ventricles, cisterns, and CSF flow spaces.
6. Vascular structures and perfusion.
7. Osseous and skull base structures.
8. Pitfall and normal-variant cross-check.
9. Synthesis and communication.