Orbital Imaging to Identify a "Lost" Lateral Rectus Muscle.

Area of Science:

• Ophthalmology
• Medical Imaging
• Surgical Science

Background:

• Esotropia, characterized by inward turning of the eye, can be caused by various factors affecting extraocular muscles.
• Accurate assessment of extraocular muscle integrity is crucial for diagnosing and managing strabismus.

Observation:

• A 36-year-old male presented with significant esotropia and restricted abduction in the right eye.
• Initial computed tomography (CT) scan of the orbits suggested the absence of the right lateral rectus muscle.

Findings:

• Intraoperative findings revealed a visually normal lateral rectus muscle, contradicting the preoperative CT scan.
• Postoperative magnetic resonance imaging (MRI) confirmed the presence of the lateral rectus muscle, but demonstrated significant atrophy.

Implications:

• This case underscores the potential for discrepancies between different imaging modalities (CT vs. MRI) and surgical findings in evaluating orbital muscles.
• It highlights the importance of considering muscle atrophy as a cause for limited ocular motility, even when initial imaging suggests absence.
• Further investigation into the diagnostic accuracy of imaging techniques for detecting subtle muscle abnormalities is warranted.