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Extraocular Muscle Enlargement in Acromegaly.
Rachel L McInnis1, Hani Rjoob, Pavlo Ohorodnyk
1Departments of Ophthalmology (RLM, JAF, LLCDB), Medicine-Endocrinology & Metabolism (HR, SHMVU), Medical Imaging (PO), and Clinical Neurological Sciences (JAF, LLCDB), Western University, London, Canada.
Summary
Acromegaly is linked to significantly larger extraocular muscles (EOMs). This study found enlarged EOMs in acromegaly patients compared to controls, suggesting a potential diagnostic or monitoring marker.
Area of Science:
- Endocrinology
- Ophthalmology
- Radiology
Background:
- Acromegaly, a condition caused by excess growth hormone, may affect various tissues.
- The impact of acromegaly on extraocular muscle (EOM) size is not well-established.
Purpose of the Study:
- To investigate whether acromegaly is associated with increased EOM size at diagnosis.
- To compare EOM dimensions in acromegaly patients with a control group.
Main Methods:
- Retrospective review of 17 acromegaly patients and 18 controls with nonfunctioning pituitary adenomas.
- CT scans were analyzed to measure the diameter and cross-sectional area of four EOMs.
- Age and sex matching were used for control selection.
Main Results:
- Acromegaly patients exhibited significantly larger mean diameters for all four measured EOMs compared to controls (P < 0.001).
- Specific mean diameters for superior, inferior, medial, and lateral recti were notably greater in the acromegaly group.
Conclusions:
- Acromegaly is associated with significantly enlarged extraocular muscles at presentation.
- Enlarged EOMs may serve as a potential indicator in acromegaly patients.
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