A study comparing SPECT with CT and MRI after closed head injury

Area of Science:

• Neurology
• Radiology
• Nuclear Medicine

Background:

• Closed head injury can cause subtle neurological deficits not always detected by standard imaging.
• Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) have limitations in visualizing certain types of brain injury.

Purpose of the Study:

• To evaluate the utility of SPECT with 99m-Technetium hexamethyl-propylene-amineoxime (HMPAO) in detecting cerebral lesions after closed head injury.
• To compare SPECT findings with CT and MRI in identifying focal cerebral lesions.
• To correlate SPECT findings with clinical outcomes and cerebral blood flow.

Main Methods:

• Nineteen patients with closed head injury underwent SPECT imaging using the lipophilic tracer 99m-Technetium hexamethyl-propylene-amineoxime (HMPAO).
• SPECT results were compared with findings from CT and MRI scans.
• Cerebral blood flow was measured, and correlations with clinical disability (Glasgow Outcome Scale) were assessed.

Main Results:

• SPECT identified significantly more focal cerebral lesions than CT or MRI, with many lesions not visible on conventional imaging.
• Severely disabled patients exhibited a higher number of SPECT lesions and lower cerebral blood flow compared to less disabled patients.
• A significant correlation was found between the Glasgow Outcome Scale grade and global cerebral blood flow.

Conclusions:

• SPECT with 99m-Technetium hexamethyl-propylene-amineoxime (HMPAO) is a sensitive tool for detecting cerebral lesions post-head injury.
• SPECT findings may explain clinical signs not evident on CT or MRI.
• SPECT can complement clinical evaluation in assessing outcomes after head injury.