**5. Nerves and muscles**

Although peripheral neuropathy has been reported in CO intoxication (Choi 1982), only electrophysiological studies but not neuroimaging studies are available (Choi 1982). Skeletal muscle injuries have been reported in CO intoxication. In one case report, skeletal muscle MRI was performed showing hyperintensity lesions in T2WI of the thigh muscles three months after CO intoxication (Chen, Huang et al. 2010). The muscle biopsy in this patient proved the diagnosis of heterotopic ossification selectively involving the iliopsoas, the tensor fascia lata, rectus femoris, sartorius and quadriceps muscles. Another study using Tc99m-sestamibi SPECT to evaluate the skeletal muscular injuries in 25 patients after CO intoxication showed decreased uptake in the patient group as compared with the controls (Huang, Chang et al. 2011). The low uptake was related to mitochondrial dysfunction.

Fig. 12. Planar view of technetium-99m-sestamibi (99mTc-MIBI) in the evaluation of muscle injury in a patient with carbon monoxide intoxication.

Compared with muscle 99mTc-MIBI of a normal control (12A), a 59-year-old man showed decreased 99mTc-MIBI uptake in the thigh muscles two months after CO intoxication (12B).
