Received 13 May 2008; received in revised form 20 October 2008; accepted 22 October 2008. published online 22 January 2009.
Objective
The pathophysiology of monocular elevation deficiency is poorly understood. The goal of this study was to determine the appearance of the extraocular muscles and the oculomotor nerve.
Design
Observational case series.
Participants
Six patients with monocular elevation deficiency.
Methods
Ophthalmologic examination and thin-sectioned magnetic resonance imaging (MRI) at the brainstem level as well as across the orbit in 6 patients were performed.
Main Outcome Measures
Ocular alignment and movement, extraocular muscles, and the oculomotor nerve on MRI.
Results
One out of 6 patients with monocular elevation deficiency showed focal thickening of the inferior rectus muscle near the orbital apex. The 5 remaining patients showed normal extraocular muscles and the oculomotor nerves on MRI.
Conclusions
Focal thickening of the inferior rectus muscle may partially explain the cause of restricted gaze. In addition, the finding of normal oculomotor nerves might support an underlying deficit in the unilateral center for upgaze as the etiology of monocular elevation deficiency.
Financial Disclosure(s)
The authors have no proprietary or commercial interested in any materials discussed in this article.
Available online: January 22, 2009.
1Department of Radiology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seoungnam, Korea
2Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seoungnam, Korea
Correspondence: Jeong-Min Hwang, MD, Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, 166, Gumiro, Bundang-gu, Seongnam, Gyeonggi-do 463-707, Korea
Manuscript no. 2008-573.
Financial Disclosure(s): The authors have no proprietary interest in any materials discussed in this article.
ABSTRACT