Pretruncal nonaneurysmal SAH (PNSAH)

Question 1

Pretruncal nonaneurysmal SAH AKA

Answer 1

perimesencephalic nonaneurysmal SAH

Question 2

Etiology PNSAH

Answer 2

1-pontine abnormality resembling a capillary telangiectasia was demonstrated on MRI
2- association with abnormal venous anatomy, including primitive variants of the basal vein of Rosenthal
3- hemorrhage secondary central cerebral venous hypertension, cavernous malformation,basilar dissection , capillary telangiectasia

Question 3

Mean age

Answer 3

50 ( 3-70 y)

Question 4

Liliequist’s membrane (LM)

Answer 4

Separate interpeduncular and chiasmatic cistern
LM have 2 leaflet➡️

diencephalic membrane( thicker) ➡️ separate interpeduncular cistern from the chiasmatic cistern medially and

from the carotid cisterns laterally

inferior leaflet mesencephalic membrane➡️ interpeduncular from the prepontine cistern.

Question 5

Low pressure source

Answer 5

carotid or prepontine cistern

Question 6

High pressure or anurysum 🚨

Answer 6

chiasmatic cistern

Question 7

Radiological criteria

Answer 7

Blood inferior LM
If extend to criteria chiasmatic, Sylvian, or interhemispheric cisterns should be viewed with suspicion 🚨
If BA bifurcation aneurysm + radiological criteria must do angio 🚨

Question 8

Anatomical criteria

Answer 8

Question 9

Repeat angio

Answer 9

If patient meet the PNSAH criteria no need to reapeat

Question 10

🚫 not recommended in TX

Answer 10

Triple H
CCB
Activity resetriction
ASM
Lower BP
Surgical exploration