Effects of intravascular laser phototherapy on delayed neurological sequelae after carbon monoxide intoxication as evaluated by brain perfusion imaging: A case report and review of the literature

BACKGROUND: Delayed neurological sequelae (DNS) caused by carbon monoxide (CO) intoxication poses considerable treatment challenges for clinical practitioners. In this report, we used nuclear medicine imaging and the Mini-Mental State Examination (MMSE) to evaluate the effectiveness of intravascular laser irradiation of blood (ILIB) therapy for the management of DNS. CASE SUMMARY: A 51-year-old woman presented to our medical center experiencing progressive bradykinesia, rigidity of limbs, gait disturbance, and cognitive impairment. Based on her neurological deficits, laboratory tests and imaging findings, the patient was diagnosed with delayed neurological sequelae of CO intoxication. She received intensive rehabilitation and ILIB therapy during 30 sessions over 2 mo after diagnosis. Brain single-photon emission computed tomography was performed both prior to and after ILIB therapy. The original hypoperfusion area in bilateral striata, bilateral frontal lobe, right parietal lobe, and bilateral cerebellum showed considerable improvement after completion of therapy. The patient’s MMSE score also increased markedly from 6/30 to 25/30. Symptoms of DNS became barely detectable, and the woman was able to carry out her daily living activities independently. CONCLUSION: ILIB therapy could facilitate recovery from delayed neurological sequelae in patients with CO intoxication, as demonstrated by improved cerebral blood flow and functional outcomes in our patient.