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Evaluation of the olfactory nerve transport function by SPECT-MRI fusion image with nasal thallium-201 administration
Hideaki Shiga1, Junichi Taki, Masato Yamada
1Department of Otorhinolaryngology-Head and Neck Surgery, Kanazawa Medical University, Kahokugun, Ishikawa, Japan. shigah@kanazawa-med.ac.jp
Purpose:
The aim of this study was to visualize the human olfactory transport pathway to the brain by performing imaging after nasal thallium-201 ((201)Tl) administration.
Procedures:
Healthy volunteers were enrolled in this study after giving informed consent (five males, 35-51 years old). The subjects were nasally administered (201)TlCl into either the olfactory cleft. Twenty-four hours later, uptake of (201)Tl was detected by a single photon emission computed tomography (SPECT)/X-ray computed tomography hybrid system. For each subject, an MRI image was obtained and merged with the SPECT image.
Results:
The peak of the (201)Tl uptake entered into the olfactory bulb in the anterior skull base through the cribriform lamina 24 h after nasal administration of (201)Tl. No participant had olfactory disturbance after treatment.
Conclusions:
Nasal (201)Tl administration was safely used to assess the direct pathway to the brain via the nose in healthy volunteers with normal olfactory threshold.
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