Reversible cerebral hypoperfusion observed with Tc-99m HMPAO SPECT in reversible dementia caused by hypothyroidism.
A 69-year-old man had hypothyroid dementia as a result of I-131 therapy and an overdose of methimazole. Tc-99m HMPAO SPECT revealed diffuse cerebral hypoperfusion. The findings of brain SPECT normalized with the disappearance of symptoms and a return to the euthyroid state. There was a 25% or 26% reduction of the mean cerebral blood flow during dementia. This may be the first report in which SPECT brain imaging revealed reversible hypoperfusion associated with reversible hypothyroid dementia.
Kinuya
S
S
Department of Nuclear Medicine, Kanazawa University School of Medicine, Ishikawa, Japan.
Michigishi
T
T
Tonami
N
N
Aburano
T
T
Tsuji
S
S
Hashimoto
T
T
D000368:Aged; D013956:Antithyroid Agents / Q000009:adverse effects*; D001921:Brain / Q000000981:diagnostic imaging; D002560:Cerebrovascular Circulation; D003704:Dementia / Q000000981:diagnostic imaging / Q000209:etiology*; D006111:Graves Disease / Q000532:radiotherapy*; D006801:Humans; D007037:Hypothyroidism / Q000150:complications* / Q000209:etiology; D007457:Iodine Radioisotopes / Q000009:adverse effects*; D008297:Male; D008713:Methimazole / Q000009:adverse effects*; D019275:Radiopharmaceuticals; D019690:Technetium Tc 99m Exametazime; D015899:Tomography, Emission-Computed, Single-Photon
D013956:Antithyroid Agents; D007457:Iodine Radioisotopes; D019275:Radiopharmaceuticals; D019690:Technetium Tc 99m Exametazime; D008713:Methimazole