Purpose: The aim of this study was to determine the effectiveness of using 99mTc-sestamibi thigh SPECT/CT imaging for evaluating myopathy in cerebrotendinous xanthomatosis (CTX).
Patients and Methods: Four genetically proven CTX patients (Family I, Cases I-1 and I-2; Family II, Cases II-1 and II-2) were included. They all underwent muscle biopsies for histopathologic and ultrastructural studies. Immunohistochemical staining for vinculin expression was also performed. 99mTc-sestamibi thigh SPECT/CT imaging was conducted on all 4 CTX patients, and both visual interpretation and muscle-to-background (M/B) ratio count were applied for assessment. Correlation analysis of the imaging findings and results of the ultrastructural and immunohistochemical studies was done.
Results: In the 99mTc-sestamibi thigh SPECT/CT imaging study, all 4 CTX cases had abnormal scores of visual interpretation and M/B ratios. The ultrastructural features of the skeletal muscle of the 4 CTX cases showed mitochondrial and membrane system abnormalities, with increased depositions of metabolites. They also had abnormal increases in vinculin expression after immunohistochemical staining of the skeletal muscle.
Conclusions: This is the first report on the use of 99mTc-sestamibi thigh SPECT/CT imaging to assess the mitochondrial status of CTX. The imaging findings may have a correlation with the ultrastructural and immunohistochemical findings on skeletal muscle. Although the 99mTc-sestamibi thigh SPECT/CT imaging is not specific for CTX, this noninvasive in vivo assessment can be an important tool for the detection and follow-up study of skeletal muscle involvement in CTX.
From the Departments of *Neurology and †Nuclear Medicine, Chang Gung Memorial Hospital-Kaohsiung Medical Center and Chang Gung University College of Medicine, Kaohsiung; and ‡School of Traditional Chinese Medicine, Chang Gung University, Taoyuan, Taiwan.
Received for publication March 21, 2013; and revision accepted May 31, 2013.
T.-L.P. and W.-N.C. contributed equally to this work.
Conflicts of interest and sources of funding: This study was supported in part by grant CMRPG8B1001 from Chang Gung Memorial Hospital.
Reprints: Wen-Neng Chang, MD, Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, 123, Ta-Pei Road, Niaosung, Kaohsiung, Taiwan. E-mail: firstname.lastname@example.org.