1. Differentiating Normal Pressure Hydrocephalus from Alzheimer Disease and Healthy Controls: Sulcal Depth Alexander M. Le, M.S., Benjamin Ades-Aron, M.S., Hersh Patel, B.S., James Golomb, MD, Henry Rusinek, PhD, Ajax George, MD
ASNR 2016

2. Normal Pressure Hydrocephalus (NPH)
Population:
Elderly, 6th-7th decade
Triad:
gait disturbance
cognitive deficits
urinary incontinence
Diagnosis
Lumbar tap test
Treatment
Surgical Shunt
Normal pressure hydrocephalus: Treatable neurological syndrome of the elderly
Classic Triad: 1) gait disturbance 2) cognitive deficits 3) urinary incontinence
Narrowing of sylvian fissure
Normal
Focal sulcal dilatation
Highly enlarged sylvian fissure

3. Imaging findings Ventriculomegaly Parietal compression
Tight high-convexity of medial subarachnoid spaces
Enlarged sylvian fissures
Focal sulcal dilatation
Purpose: to identify cortical sulcal patterns using sulcal depth measurements to characterize NPH
Sylvian fissure narrowing
Normal
Moderately enlarged
Highly enlarged

4. Disproportionately enlarged sulci hydrocephalus (DESH)
Ventriculomegaly
Tight high-convexity and medial subarachnoid spaces
Disproportionate distribution of CSF in the subarachnoid space
Inferior > Superior
Enlarged Sylvian fissures

5. Methods Patients 22 NPH (non-DESH) 11 NPH (DESH) 23 Alzheimer Disease
25 Healthy Controls

6. Methods High-resolution T1-weighted MPRAGE sequences, 3T MRI system
FreeSurfer software (Linux)
Segmentation
Reconstruction of pial surface
Reconstruction of inner skull surface
MATLAB in-house software
Measurement of the sulcal depth: length of vector from the sulci to the inner table of the skull
Statistical analysis
Vertex-wise t-tests co-varying for age and total-intracranial volume
Clusterwise correction for multiple comparisons

7. Study
Results
p-value
HC vs NPH (non-DESH)
NPH (non-DESH) has shallower sulci in pre-central sulcus vs HC
(P*** < 0.005)
HC vs NPH (DESH)
NPH (DESH) has shallower sulci in central sulcus vs HC
HC vs AD
No statistical differences
(P > 0.05)
NPH (non-DESH) vs AD
NPH (DESH) vs AD
NPH (DESH) has shallower sulci in central sulcus vs Alzheimer Disease
(P* < 0.05)
NPH (non-DESH) vs DESH
NPH (non-DESH) has deeper sulci in central sulcus vs NPH (DESH)

8. Conclusion
NPH (non-DESH) and NPH (DESH) patients exhibit shallower sulci in pre-central and central sulcus compared to HC and AD
Enlarged ventricles from within brain compressing gyri against inner skull
No difference in the sylvian fissure depth

9. Acknowledgements Dr. Ajax George, MD Dr. James B. Golomb, MD
Benjamin Ades-Aron, BS, MS
Dr. Henry Rusinek, PhD