title: Visualization of frontal postural hypoperfusion in patients with Takayasu arteritis with upright 99Tcm-HMPAO brain SPET.
abstract: Takayasu arteritis is a chronic inflammatory angiopathy involving the cerebral arteries. We performed upright and supine 99Tcm-HMPAO brain single photon emission tomography (SPET) to investigate the cerebral perfusion pattern in eight patients with Takayasu arteritis, and we compared the results with those acquired using 123I-IMP and acetazolamide in six patients. SPET images were evaluated visually and semi-quantitatively. Hypoperfusion was visually detected in all eight patients during the provocative upright test with 99Tcm-HMPAO, and in three of six tested using acetazolamide and 123I-IMP. Semiquantitative analysis revealed that the mean cortical-to-cerebellar ratio in the upright position was significantly changed compared to that in the supine position in the right frontal area (from 0.86 +/- 0.07 to 0.91 +/- 0.09; P < 0.05). Change was also seen in the left frontal area (from 0.85 +/- 0.08 to 0.91 +/- 0.08; P < 0.05). No significant change was seen in other cortical areas with the upright test or in any areas with the acetazolamide test. We postulate that reduced arterial compliance may cause frontal postural hypoperfusion in patients with Takayasu arteritis due to poor functioning of autoregulation and arterial stenosis or occlusion. We conclude that the provocative upright test with 99Tcm-HMPAO brain SPET can detect abnormal patterns of cerebral perfusion in patients with Takayasu arteritis that might be missed by brain SPET using 123I-IMP and acetazolamide.
authors.affiliation: Department of Radiology, National Cardiovascular Center, Osaka, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Kume
authors.forename: K
authors.initials: K
authors.lastname: Hayashida
authors.forename: I H
authors.initials: IH
authors.lastname: Cho
authors.forename: Y
authors.initials: Y
authors.lastname: Shimotsu
authors.forename: Y
authors.initials: Y
authors.lastname: Nishioeda
authors.forename: N
authors.initials: N
authors.lastname: Matsunaga
mesh_terms: D000086:Acetazolamide; D000293:Adolescent; D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D001921:Brain / Q000000981:diagnostic imaging*; D002531:Cerebellum / Q000098:blood supply; D002536:Cerebral Arteries / Q000000981:diagnostic imaging; D002540:Cerebral Cortex / Q000098:blood supply; D004232:Diuretics; D004837:Epinephrine / Q000097:blood; D005260:Female; D006801:Humans; D007024:Hypotension, Orthostatic / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011857:Radiographic Image Interpretation, Computer-Assisted; D019275:Radiopharmaceuticals; D013625:Takayasu Arteritis / Q000000981:diagnostic imaging*; D019690:Technetium Tc 99m Exametazime; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D004232:Diuretics; D019275:Radiopharmaceuticals; D019690:Technetium Tc 99m Exametazime; D000086:Acetazolamide; D004837:Epinephrine