Abnormal perfusion of the pituitary gland secondary to dural arteriovenous fistulas in the cavernous sinus: dynamic MR findings.
OBJECTIVE
If venous congestion is the primary cause of pituitary gland enlargement in cases of dural arteriovenous fistulas (AVFs), other abnormal pituitary findings may be detectable on MR images. We sought to investigate the perfusion abnormality of the pituitary gland secondary to dural AVFs in the cavernous sinus and to clarify its clinical importance.


METHODS
Nine consecutive patients (all female; age range, 50-77 years) with dural AVFs in the cavernous sinus underwent prospective MR examinations, including dynamic studies, before and after therapy. Their clinical signs and symptoms were recorded. Two radiologists visually evaluated the enhancement patterns of the anterior pituitary gland. Dynamic MR curves were obtained by locating regions of interest at the center and bilateral peripheral areas of the anterior pituitary gland on coronal images. MR images obtained in five healthy individuals served as controls.


RESULTS
No patient had symptoms of hypopituitarism or other endocrine abnormalities. Asymmetric pituitary enhancement was found in five patients; the side with the dural AVF was less enhancing. This finding disappeared after therapy. Although asymmetric enhancement was not detected in the remaining four patients, statistical analysis showed significantly delayed enhancement of the pituitary gland in the patients compared with enhancement patterns in control subjects. After treatment, this delay improved significantly. The pituitary gland significantly decreased in size after treatment.


CONCLUSIONS
Perfusion of the pituitary gland is impaired in patients with a dural AVF in the cavernous sinus. This finding is probably due to venous congestion of the pituitary gland caused by high pressure in the cavernous sinus; it is usually not related to pituitary dysfunction.
Shigematsu
Yoshinori
Y
Department of Radiology, Kumamoto University School of Medicine, Japan.
Korogi
Yukunori
Y
Kitajima
Mika
M
Ishii
Akihiko
A
Liang
Luxia
L
Yamura
Masayuki
M
Kawanaka
Kouich
K
Takahashi
Mutsumasa
M
D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction; D002426:Cavernous Sinus / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000473:pathology*; D020785:Central Nervous System Vascular Malformations / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010903:Pituitary Gland, Anterior / Q000098:blood supply* / Q000473:pathology; D011446:Prospective Studies
D003287:Contrast Media; D019786:Gadolinium DTPA