접수번호: 2009-045 Korean Journal of Ophthalm ology 2009;23:329-331 ISSN : 1011-8942 DOI : 10.3341/kjo.2009.23.4.329 A Case of Pseudo-Duane’s Retraction Syndrome With Old Medial Orbital Wall Fracture Seung Hee Lee, MD, Jae Hyung Lee, MD, Soo Yoon Lee, MD, Sook Young Kim, MD Department of Ophthalmology, Daegu Catholic University College of Medicine, Daegu, Korea We report a case of pseudo-Duane’s retraction syndrome with entrapment of the medial rectus muscle in an old medial orbital wall fracture presenting identical clinical symptoms as Duane’s retraction syndrome. A15-year-old boy presented with persistent limited right eye movement since a young age. Examination showed marked limited abduction, mildly limited adduction, and globe retraction accompanied by narrowing of the palpebral fissure during attempted adduction in the right eye. He showed a right esotropia of 16 prism diopters and his head turned slightly to the right. A slight enophthalmos was noted in his right eye. A computed tomography scan demonstrated entrapment of the medial rectus muscle and surrounding tissues in an old medial orbital wall fracture. A forced duction test revealed a marked restriction of abduction in the right eye. A 5 mm recession of the right medial rectus muscle was performed. Post- operatively, the patient’s head turn and esotropia in the primary position were successfully corrected, but there was still some limitations to his ocular movement. The importance of several tests such as the forced duction test and an imaging study should be emphasized in making a diagnosis for limitation of eye movement. Korean J Ophthalmol 2009;23:329-331 ⓒ 2009 by the Korean Ophthalmological Society. Key Words: Duane’s retraction syndrome, Medial orbital wall fracture, Pseudo-Duane’s retraction syndrome Since Alexander Duane published a paper in 1905 des- cribing what has come to be known as Duane’s retraction syndrome, Thomas Duane reported a similar, yet different set of symptoms and signs as ‘pseudo-Duane’s retraction syndrome’ in 1976.1 In the most common type of Duane’s retraction syndrome, there is markedly restricted abduction with eyeball retraction and narrowing of the palpebral fissure on adduction.2 In pseudo-Duane’s retraction syndrome, how- ever, abduction of the affected eye is possible to some extent, and the globe retraction occurs on abduction accompanied by narrowing of the palpebral fissure presenting the opposite features as those of classic Duane’s retraction syndrome. The etiology is also completely different from those of Duane’s retraction syndrome. Pseudo-Duane’s retraction syndrome has been reported as being caused by acquired or congenital factors that affect the medial rectus muscle. Entrapment of the medial rectus muscle in a medial orbital wall fracture has been known to be the most common cause.3 We report a case of pseudo-Duane’s retraction syndrome with entrapment of the medial rectus muscle in an old medial orbital wall fracture, presenting very similar clinical features as those of classic Duane’s retraction syndrome. The pre- Received: April 22, 2009 Accepted: October 29, 2009 Reprint requests to Sook Young Kim, MD. Department of Ophthalmology, Daegu Catholic University College of Medicine, #3056-6 Daemyeong 4-dong, Nam-gu, Daegu 705-718, Korea. Tel: 82-53-650-4728, E-mail: kimsy@cu.ac.kr sentation is contradictory to previous reports of pseudo- Duane’s retraction syndrome. Case Repo rt A 15-year-old boy had complained of motility limitation in the right eye since a young age. His visual acuity was 20/20 in each eye, although an ocular motility examination revealed markedly limited abduction and mildly limited adduction in his right eye (Fig. 1). On attempted adduction of the right eye, globe retraction (Fig. 2) with narrowing of the palpebral fissure was observed, and there mild upshoot and downshoot were also observed (Fig. 1). The palpebral fissure of the right eye was slightly widened on attempted abduction. An alternate prism cover test revealed a 16 prism diopters (PD) right esotropia (ET) in the primary position, 25 PD ET in right gaze, 10 PD ET in left gaze at dist- ance fixation, and 4 PD ET at near fixation. He assumed a compensatory face turn to the right and did not comp- lain of diplopia. No living member on either the paternal or maternal side had a squint. Duane’s retraction syndrome was inferred as the diagnosis until we noted that the patient’s right eye had slight enophthalmos. Hertel’s exophthalmo- metry revealed a 1.5 mm difference between both eyes and the margin reflex distance 1 was 0.5 mm in the right eye. Computed tomography of the orbits was performed and demonstrated an old medial orbital wall fracture with entrapment of the medial rectus muscle and surrounding tissues (Fig. 3). However, there was no history of trauma 329