Assessment of alterations in regional cerebral blood flow in patients with hypothyroidism due to Hashimoto's thyroiditis.
OBJECTIVE
The aim of this study was to assess regional cerebral blood flow (rCBF) using detailed semiquantitative analysis of Technetium-99m hexamethylpropyleneamine (HMPAO) brain single-photon emission computerized tomography (SPECT) in patients with hypothyroidism due to autoimmune thyroiditis.


METHODS
Twenty patients (mean age: 42+/-9 yr) and 12 control subjects (mean age: 35.4+/-8.5 yr) were included in this study. The corticocerebellar rCBF ratios were obtained from 52 cerebral areas on 6 transaxial slices. By using control group rCBF ratios, lower reference values (RLV) (average ratio -2 SD) were calculated and the regions below RLV having an rCBF ratio were considered as abnormal decrease (hypoperfused) areas.


RESULTS
Significant reduced rCBF rates were measured for 15 (29%) cortical regions for the patient group. The areas in which significant reduced rCBF were demonstrated in the patient group were as follows: a) in the right hemisphere: superior frontal (slice 1 and 2), inferior frontal (slice 1), anterior temporal (slice 1 and 2), precentral gyrus (slice 1 and 2), postcentral gyrus (slice 1 and 2), and parietal cortex; b) in the left hemisphere: superior frontal (slice 1 and 2), inferior frontal (slice 1), caudate nucleus, and parietal cortex. The hypoperfusion was calculated in 154 (14%, 94 right and 60 left) cortical regions out of 1040 regions in the patient group.


CONCLUSIONS
These findings indicate that the alteration of rCBF in patients with hypothyroidism due to Hashimoto's thyroiditis before T4 therapy can be demonstrated with brain SPECT. Additionally, the degree of rCBF abnormalities could be determined with brain SPECT in patients with hypothyroidism due to Hashimoto's thyroiditis with or without neurologic or psychiatric symptoms.
Kaya
M
M
Department of Nuclear Medicine, Hospital of the University of Trakya, 22030 Edirne, Turkey. meryemk@trakya.edu.tr
Cermik
T F
TF
Bedel
D
D
Kutucu
Y
Y
Tuglu
C
C
Yigitbasi
O N
ON
D000328:Adult; D002560:Cerebrovascular Circulation / Q000502:physiology*; D054022:Cerebrum / Q000033:anatomy & histology / Q000378:metabolism / Q000473:pathology; D005260:Female; D050031:Hashimoto Disease / Q000188:drug therapy / Q000503:physiopathology*; D006801:Humans; D007037:Hypothyroidism / Q000188:drug therapy / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D019275:Radiopharmaceuticals; D012039:Regional Blood Flow / Q000502:physiology*; D019690:Technetium Tc 99m Exametazime; D013961:Thyroid Gland / Q000033:anatomy & histology / Q000378:metabolism; D013974:Thyroxine / Q000627:therapeutic use; D015899:Tomography, Emission-Computed, Single-Photon
D019275:Radiopharmaceuticals; D019690:Technetium Tc 99m Exametazime; D013974:Thyroxine