Acute carbon monoxide poisoning and its delayed encephalopathy have obvious damage to the central nervous system. There are different neuroimaging changes in different stages of the disease, and they are relatively specific. This article reviews the clinical research progress on the imaging changes of carbon monoxide poisoning and delayed encephalopathy, including computed tomography (CT) , conventional magnetic resonance imaging (MRI) , diffusion weighted imaging (DWI) , diffusion tensor imaging (DTI) , diffusion kurtosis imaging (DKI) , magnetic resonance spectroscopy (MRS) and other imaging changes reflecting the function and metabolic state of the brain tissue.
Humans ; Brain Diseases/etiology* ; Carbon Monoxide Poisoning/diagnostic imaging* ; Diffusion Magnetic Resonance Imaging ; Diffusion Tensor Imaging ; Magnetic Resonance Imaging ; Tomography, X-Ray Computed ; Magnetic Resonance Spectroscopy

A 59-year-old man with a history of major depression was found by his wife to be unconscious and foaming at the mouth. On arrival at the emergency department, the patient was noted to be unresponsive. Computed tomography of the brain showed symmetrical ill-defined areas of hypoattenuation involving the medial aspects of both lentiform nuclei, while magnetic resonance images of the brain showed symmetrical increased signal in the bilateral globi pallidi on diffusion weighted, T2-weighted and fluid attenuated inversion recovery sequences. These findings were those of acute carbon monoxide poisoning. Despite aggressive treatment, the patient's condition continued to deteriorate and he eventually passed away. The various imaging findings of carbon monoxide poisoning in the brain and the differential diagnoses are discussed.
Brain ; diagnostic imaging ; Carbon Monoxide Poisoning ; diagnosis ; diagnostic imaging ; Depressive Disorder, Major ; complications ; Diagnostic Imaging ; Fatal Outcome ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Pulmonary Edema ; pathology ; Radiography, Thoracic ; Suicide, Attempted ; Tomography, X-Ray Computed

OBJECTIVETo investigate clinical and imaging characteristics of delayed encephalopathy after acute carbon monoxide poisoning (DEACMP) and their relationship to the prognosis.

METHODSThe clinical, CT and MRI findings in 46 patients with DEACMP were analysed and compared.

RESULTSThe main manifestations of the disease were mental and extrapyramidal impairment. CT scan showed diffuse low density changes in bilateral cerebral white matter, bilateral or unilateral globus pallidus or basal ganglia areas. The MRI showed necrosis and degeneration of glodus pallidus and cerebral white matter demyelination mainly around the ventricles, with high signal intensity in T(2)-weighted and equal or low signal intensity in T(1)-weighted as well as the lesions in hippocampus and brain stem. There was the sign of encephalatrophy in the late stage. The positive detectable rate of MRI was 82.1%, higher than that of CT, 43.2%. MRI was more sensitive than CT.

CONCLUSIONThe prognosis of the patients is closely related with the age, time of come after DEACMP and the effectiveness of treatment. Both CT and MRI are valuable in the diagnosis and evaluation of the prognosis for DEACMP. MRI is more sensitive than CT in the diagnosis of DEACMP.

Acute Disease ; Adult ; Aged ; Brain ; diagnostic imaging ; pathology ; Brain Diseases ; chemically induced ; diagnosis ; diagnostic imaging ; Carbon Monoxide Poisoning ; complications ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Prognosis ; Sensitivity and Specificity ; Tomography, X-Ray Computed

Adolescent ; Adult ; Aged ; Brain ; blood supply ; diagnostic imaging ; Carbon Monoxide Poisoning ; diagnostic imaging ; Child ; Female ; Humans ; Male ; Middle Aged ; Tomography, Emission-Computed, Single-Photon

We used single photon emission computed tomography (SPECT) with technetium-99m hexamethylpropylene amine oxime (99mTc-HM-PAO) in 14 studies on 6 patients with delayed neurologic sequelae from carbon monoxide (CO) poisoning to determine whether any changes in cerebral blood flow could be correlated with clinical or computed tomographic evidence of delayed deficits. Among the six initial CT brain scans, two showed low density of both basal ganglia and two showed decreased density of the cerebral white matter. There was no correlation between the clinical outcome and the findings of the follow-up CT brain scans. Of the two SPECTS with 99mTc-HM-PAO performed during acute anoxic insult, one showed focal hypoperfusion which appeared 20 days prior to the onset of delayed neurologic sequelae after CO poisoning. Seven SPECTs in the six patients performing the delayed phase showed diffuse patched patterns of hypoperfusion which improved on follow-up images. There was good correlation between the clinical outcome and the findings of the 99mTc-HM-PAO SPECT. In preliminary conclusion, 9Tc-HM-PAO brain SPECT can be used for predicting or evaluating the outcome of delayed neurologic sequelae after CO poisoning. Cerebral vascular changes may be the possible cause of hypoperfusion in patients with CO poisoning.
Adult ; Aged ; Brain Diseases/etiology/*radionuclide imaging ; Carbon Monoxide Poisoning/*complications ; Female ; Humans ; Middle Aged ; Organotechnetium Compounds/*diagnostic use ; Oximes/*diagnostic use ; Predictive Value of Tests ; Technetium Tc 99m Exametazime ; Time Factors ; *Tomography, Emission-Computed, Single-Photon