Direct sagittal computed tomography in Graves' ophthalmopathy

Area of Science:

• Ophthalmology
• Radiology
• Medical Imaging

Background:

• Standard axial transverse orbital CT scans provide limited visualization of superior and inferior rectus muscles.
• Oblique sectioning of these muscles on axial scans can hinder the detection of enlargement in Graves' disease.

Purpose of the Study:

• To evaluate the efficacy of sagittal and coronal orbital CT scans in diagnosing Graves' ophthalmopathy.
• To compare the diagnostic utility of different orbital CT scan planes for visualizing rectus muscle enlargement.

Main Methods:

• Direct sagittal and coronal orbital CT scans were acquired using a wide-aperture scanner and special accessory table.
• Images from sagittal, coronal, and axial transverse planes were compared in patients with Graves' ophthalmopathy.

Main Results:

• Sagittal and coronal CT scans effectively demonstrate enlargement of the superior or inferior rectus muscles.
• These planes can identify muscle enlargement even when medial and lateral recti appear normal.
• Scans angled approximately 20 degrees to the sagittal plane offer superior orbital anatomy visualization.

Conclusions:

• Sagittal and coronal orbital CT imaging enhances the detection of rectus muscle enlargement in Graves' ophthalmopathy.
• These imaging planes are superior to standard axial scans for evaluating superior and inferior rectus muscles.
• Optimized scan angulation improves visualization of orbital anatomy.