Fig. 6.9 Orbital T2-weighted MRI in chronic left abducens palsy. Axial view above shows thinning and lateral inflection of palsied LR

6 muscle, which in coronal view below is seen to have reduced cross-section

muscle, entering the IO in the EOM’s posterior surface relatively superficially in the orbit when compared with innervation to the other EOMs. Isolated acquired neuropathic IO palsy is thus anatomically possible. When it occurs, IO palsy is associated with denervation atrophy of the IO belly [78].

6.8Central Abnormalities of Vergence and Gaze

Several common causes of strabismus are not associated with abnormalities of the EOMs, motor nerves, or orbital connective tissues. The forms of strabismus arise from abnormalities in the central nervous system, some of which are structural lesions that may be imaged.

Summary for the Clinician

■Developmental esotropia and exotropia are not associated with structural abnormalities in the orbit.

6.8.1Developmental Esotropia and Exotropia

Human infantile and accommodative esotropia are not known to be associated with anatomic abnormalities in the orbit. Naturally and artificially esotropic and exotropic monkeys also exhibit latent nystagmus and other features typical of human childhood strabismus, but these monkeys have normal horizontal EOM structure, normal EOM locations, and normal intraorbital EOM innervation [79]. However, strabismic monkeys have microscopic evidence of abnormalities in visual cortical area V1 [80], and most likely also other visual cortical areas.

6.8.2Cerebellar Disease

The cerebellum contributed toward binocular alignment [81]. Hereditary cerebellar degeneration is often associated with convergence insu ciency, and in advanced cases often produces cerebellar atrophy [82]. Cerebellar or brainstem tumors may be associated with acute onset of concomitant esotropia in children [83]. Acquired cerebellar damage, such as by infarction, may produce skew deviation other strabismus.

6.8.3Horizontal Gaze Palsy and Progressive Scoliosis

Horizontal gaze palsy and progressive scoliosis is a recessive disorder of axon path finding in the central nervous system. Patients have essentially complete horizontal ophthalmoplegia despite intact EOMs and peripheral motor innervation to them, but MRI demonstrates dysplasia of the hindbrain suggestive of a sagittal fissure interrupting decussating white matter tracts [84].

References

1.Ortube MC, Bhola R, Demer JL (2006) Orbital magnetic resonance imaging of extraocular muscles in chronic progressive external ophthalmoplegia: Specific diagnostic findings. J AAPOS 10:414–418

2.Biousse V, Newman NJ (2001) Neuro-ophthalmology of mitochondrial diseases. Semin Neurol 3:275–291

3.Vilarinho L, Santorelli FM, Cardoso ML, et al (1998) MitochondrialDNAanalysisinocularmyopathy.Observations in 29 portuguese patients. Euro Neurol 39: 148–153

4.Kuriyan AE, Phipps RP, Feldon SE (2008) The eye and thyroid disease. Cur Opin Ophthalmol 19:499–506

5.Wolf AB, Yang MB, Archer SM (2007) Postoperative myositis in reoperated extraocular muscles. J AAPOS 11: 373–376

6.Capone AJ, Slamovits TL (1990) Discrete metastasis of solid tumors to extraocular muscles. Arch Ophthalmol 108:237–243

7.Demer JL (2003) A 12 year, prospective study of extraocular muscle imaging in complex strabismus. J AAPOS 6:337–347

8.Koornneef L (1982) Current concepts on the management of orbital blow-out fractures. Ann Plast Surg 9:185–200

9.Wojno TH (1987) The incidence of extraoular muscle and cranial nerve palsy in orbital floor blow-out fractures. Ophthalmol 94:682–687

10.Ortube MC, Rosenbaum AL, Goldberg RA, et al (2004) Orbital imaging demonstrates occult blow out fracture in complex strabismus. J AAPOS 8:264–273

11.Tse R, Allen L, Matic D (2007) The white-eyed medial blowout fracture. Plast Reconstr Surg 119:277–286

12.Demer JL (2004) Pivotal role of orbital connective tissues in binocular alignment and strabismus. The Friedenwald lecture. Invest Ophthalmol Vis Sci 45:729–738

13.Demer JL (2006) Current concepts of mechanical and neural factors in ocular motility. Cur Opin Neurol 19:4–13

14.Demer JL (2006) Ocular motility in a time of revolutionary paradigm shift. Invest Ophthalmol Vis Sci

15.Kono R, Poukens V, Demer JL (2002) Quantitative analysis of the structure of the human extraocular muscle pulley system. Invest Ophthalmol Vis Sci 43:2923–2932

16.Clark RA, Miller JM, Rosenbaum AL, et al (1998) Heterotopic muscle pulleys or oblique muscle dysfunction? J AAPOS 2:17–25

17.Miller JM, Demer JL Biomechanical modeling in strabismus surgery. In: Rosenbaum AL, Santiago P (eds) (1999) Clinical strabismus management: principles and techniques. Mosby, St. Louis

18.Clark RA, Miller JM, Demer JL (1997) Location and stability of rectus muscle pulleys inferred from muscle paths. Invest Ophthalmol Vis Sci 38:227–240

19.Miller JM (2007) Understanding and misunderstanding extraocular muscle pulleys. J Vision 7:1–15

20.Miller JM, Pavlovski DS, Shaemeva I (1999). Orbit 1.8 gaze mechanics simulation. Eidactics, San Francisco

21.Clark RA, Miller JM, Demer JL (1998) Displacement of the medial rectus pulley in superior oblique palsy. Invest Ophthalmol Vis Sci 39:207–212

22.Demer JL, Clark RA, Miller JM (1999) Heterotopy of extraocular muscle pulleys causes incomitant strabismus. In: Lennerstrand G (ed) Advances in strabismology. Aeolus, Buren, The Netherlands

23.Velez FG, Clark RA, Demer JL (2000) Facial asymmetry in superior oblique palsy and pulley heterotopy. J AAPOS 4:233–239

24.Demer JL, Oh SY, Clark RA, et al (2003) Evidence for a pulley of the inferior oblique muscle. Invest Ophthalmol Vis Sci 44:3856–3865

25.Rutar T, Demer JL (2009) “Heavy eye syndrome” in the absence of high myopia: A connective tissue degeneration in elderly strabismic patients. J AAPOS 13(1):36–44

26.Clark RA, Demer JL (2002) E ect of aging on human rectus extraocular muscle paths demonstrated by magnetic resonance imaging. Am J Ophthalmol 134:872–878

27.Lim L, Rosenbaum AL, Demer JL (1995) Saccadic velocity analysis in patients with digergence paralysis. J Pediatr Ophthalmol Strabismus 32:76–81

28.Clark RA, Isenberg SJ (2001) The range of ocular movements decreases with aging. J AAPOS 5:26–30

29.Krzizok TH, Schroeder BU (1999) Measurement of recti eye muscle paths by magnetic resonance imaging in highly myopic and normal subjects. Invest Ophthalmol Vis Sci 40:2554–2560

30.Kowal L, Troski M, Gilford E (1994) MRI in the heavy eye phenomenon. Aust N Zeal J Ophthalmol 22:125–126

31.Ward DM (1956) The heavy eye phenomenon. Trans Ophthalmol Soc U K 87:717–726

32.Demer JL, von Noorden GK (1989) High myopia as an unusual cause of restrictive motility disturbance. Surv Ophthalmol 33:281–284

33.Wu J, Isenberg S, DJ L (2006) Magnetic resonance imaging demonstrates neuropathology in congenital inferior division oculomotor palsy. J AAPOS 10:473–475

34.Engle EC, Goumnerov BC, McKeown CA, et al (1997) Oculomotor nerve and muscle abnormalities in congenital fibrosis of the extraocular muscles. Ann Neurol 41:314–325

35.Apt L, Axelrod N (1978) Generalized fibrosis of the extraocular muscles. Am J Ophthalmol 85:822–829

36.Brodsky MC, Pollock SC, Buckley EG (1989) Neural misdirection in congenital ocular fibrosis syndrome: Implications and pathogenesis. J Pediatr Ophthalmol Strabismus 26:159–161

37.Harley RD, Rodrigues MM, Crawford JS (1978) Congenital fibrosis of the extraocular muscles. Trans Am Ophtlalmol Soc 76:197–226

38.Demer JL, Clark RA, Engle EC (2005) Magnetic resonance imaging evidence for widespread orbital dysinnervation in congenital fibrosis of extraocular muscles due to mutations in KIF21A. Invest Ophthalmol Vis Sci 46:530–539

39.Brodsky MC (1998) Hereditary external ophthalmoplegia, synergistic divergence, jaw winking, and oculocutaneous hypopigmentation. Ophthalmology 105:717–725

40.Yamada K, Andrews C, Chan W-M, et al (2003) Heterozygous mutations of the kinesin KIF21A in congenital fibrosis of the extraocular muscles type 1 (CFEOM1). Nat Genet 35:318–321

41.Demer JL, Clark RA, Engle EC (2009) Magnetic resonance imaging evidence of an asymmetrical endophenotype in congenital fibrosis of extraocular muscles type 3. Invest Ophthalmol Vis Sci (in preparation)

642. Clark RA, Engle EC, Demer JL (2009) Magnetic resonance imaging (MRI) of the endophenotype of congenital fibrosis of the extraocular muscles type 3 (CFEOM3). Abstracts of 35th Annual Meeting of the American Association for Pediatric Ophthalmology and Strabismus. J Am Assoc Pediatr Ophthmol Strabismus 13(1):e13

43.Duane A (1905) Congenital deficiency of abduction associated with impairment of adduction, retraction movements, contraction of the palpebral fissure and oblique movements of the eye. Arch Ophthalmol 34:133–159

44.Huber A (1974) Electrophysiology of the retraction syndromes. Br J Ophthalmol 58:293–300

45.Strachan IM, Brown BH (1972) Electromyography of extraocular muscles in Duane’s syndrome. Br J Ophthalmol 56:594–599

46.Miller NR, Kiel SM, Green WR, et al (1982) Unilateral Duane’s retraction syndrome (type 1). Arch Ophthalmol 100:1468–1472

47.Hotchkiss MG, Miller NR, Clark AW, et al (1980) Bilateral Duane’s retraction syndrome. A clinical-pathologic case report. Archives of Ophthalmology 98:870–874

48.Parsa CF, Grant E, Dillon WP, et al (1998) Absence of the abducens nerve in Duane syndrome verified by magnetic resonance imaging. Am J Ophthalmol 125:399–401

49.Ozkurt H, Basak M, Oral Y, et al (2003) Magnetic resonance imaging in Duane’s retraction syndrome. J Pediatr Ophthalmol Strabismus 40:19–22

50.Kim JH, Hwang J-M (2005) Hypoplastic oculomotor nerve and absent abducens nerve in congenital fibrosis syndrome and synergistic divergence with magnetic resonance imaging. Ophthalmology 112:728–732

51.Kim JH, Hwang JM (2005) Presence of abducens nerve according to the type of Duane’s retraction syndrome. Ophthalmology 112:109–113

52.DeRespinis PA,Caputo AR,Wagner RS,et al (1993) Duane’s Retraction Syndrome. Surv Ophthalmol 38:257–288

53.Demer JL, Clark RA, Lim KH, et al (2007) Magnetic resonance imaging evidence for widespread orbital dysinnervation in dominant Duane’s retraction syndrome linked to the DURS2 locus. Invest Ophthalmol Vis Sci 48:194–202

54.Kumar D (1990) Moebius syndrome. J Med Genet 27: 122–126

55.MacDermot KD, Winter RM, Taylor D, et al (1991) Oculofacialbulbar palsy in mother and son: review of 26 reports of familial transmission within the ‘Mobius spectrum of defects’. J Med Genet 28:18–26

56.Verzijl HT, van der Zwaag B, Cruysberg JR, et al (2003) Mobius syndrome redefined: a syndrome of rhombencephalic maldevelopment. Neurology 61:327–333

57.Bielschowsky A (1939) Lectures on motor anomalies. XI. Etiology, prognosis, and treatment of ocular paralyses. Am J Ophthalmol 22:723–734

58.von Noorden GK, Murray E, Wong SY (1986) Superior oblique paralysis. A review of 270 cases. Arch Ophthalmol 104:1771–1776

59.Adler FE (1946) Physiologic factors in di erential diagnosis of paralysis of superior rectus and superior oblique muscles. Arch Ophthalmol 36:661–673

60.Scott WE, Kraft SP (1986) Classification and treatment of superior oblique palsies: II. Bilateral superior oblique palsies. In: Caldwell D (ed) Pediaric ophthalmology and strabismus: transactions of the New Orleans academy of ophthalmology. Raven, New York

61.Straumann D, Ste en H, Landau K, et al (2003) Primary position and Listing’s law in acquired and congenital trochlear nerve palsy. Invest Ophthalmol Vis Sci 44:4282–4292

62.Kushner BJ (2004) Ocular torsion: Rotations around the “WHY” axis. J AAPOS 8:1–12

63.Kushner BJ (1988) The diagnosis and treatment of bilateral masked superior oblique palsy. Am J Ophthalmol 105:186–194

64.Robinson DA (1985) Bielschowsky head-tilt test–II. Quantitative mechanics of the Bielschowsky head-tilt test. Vision Res 25:1983–1988

65.Chan TK, Demer JL (1999) Clinical features of congenital absence of the superior oblique muscle as demonstrated by orbital imaging. J AAPOS 3:143–150

66.Demer JL, Miller JM (1995) Magnetic resonance imaging of the functional anatomy of the superior oblique muscle. Invest Ophthalmol Vis Sci 36:906–913

67.Kono R, Demer JL (2003) Magnetic resonance imaging of the functional anatomy of the inferior oblique muscle in superior oblique palsy. Ophthalmology 110:1219–1229

68.Demer JL, Poukens V, Ying H, et al (2008) E ects of acute trochlear denervation on primate superior oblique (SO) muscle: di erential sparing of orbital layer. ARVO Abstracts: #4495

69.Demer JL, Miller MJ, Koo EY, et al (1995) True versus masquerading superior oblique palsies: muscle mechanisms revealed by magnetic resonance imaging. In: Lennerstrand G (ed) Update on strabismus and pediatric ophthalmology. CRC, Boca Raton (FL)

70.Kushner BJ (1987) Errors in the three-step test in the diagnosis of vertical strabismus. Ophthalmology 96:127–132

71.Brodsky ME (2003) Three dimensions of skew deviation. Br J Ophthalmol 87:1440–1441

72.Donahue SP, Lavin PJ, Hamed LM (1999) Tonic ocular tilt reaction simulating a superior oblique palsy: diagnostic confusion with the 3-step test. Arch Ophthalmol 117:347–352

73.Kono R, Okanobu H, Ohtsuki H, et al (2008) Displacement of the rectus muscle pulleys simulating superior oblique palsy. Jpn J Ophthalmol 52:36–43

74.Clark RA, Rosenbaum AL, Demer JL (1999) Magnetic

resonance imaging after surgical transposition defines the anteroposterior location of the rectus muscle pulleys. J AAPOS 3:9–14

75.Clark RA, Demer JL (2002) Rectus extraocular muscle pulley displacement after surgical transposition and posterior

fixation for treatment of paralytic strabismus. Am J Ophthalmol 133:119–128

76.Demer JL (2008) Inflection in inactive lateral rectus muscle: Evidence suggesting focal mechanical e ects of connective tissues. Invest Ophthalmol Vis Sci 49:4858–4864

77.Clark RA, Demer JL (2008) Posterior inflection of weakened lateral rectus path: Connective tissue factors reduce response to lateral rectus recession. Am J Ophthalmol 147(1):127–133.e2

78.Ela-Dalman N,Velez FG, Demer JL, et al (2008) High resolution MRI demonstrates reduced inferior oblique muscle

References 75

size in isolated inferior oblique palsy. J AAPOS 12(6): 602–607

79.Narasimhan A, Tychsen LT, Poukens V, et al (2007) Horizontal rectus muscle anatomy in naturally and artificially strabismic monkeys. Invest Ophthalmol Vis Sci 48:2576–2588

80.Tychsen L,Wong AM, Burkhalter A (2004) Paucity of horizontal connections for binocular vision in V1 of naturally strabismic macaques: Cytochrome oxidase compartment specificity. J Comp Neurol 474:261–275

81.Takagi M, Tamargo R, Zee DS (2003) Effects of lesions of the cerebellar oculomotor vermis on eye movements in primate: binocular control. Prog Brain Res 142: 19–33

82.Durig JS, Jen JC, Demer JL (2002) Ocular motility in genetically defined autosomal dominant cerebellar ataxia. Am J Ophthalmol 133:718–721

83.Williams AS, Hoyt CS (1989) Acute comitant esotropia in children with brain tumors. Arch Ophthalmol 107: 376–378

84.Jen JC, Chan WM, Bosley TM, et al (2004) Mutations in a human ROBO gene disrupt hindbrain axon pathway crossing and morphogenesis. Science 304:1509–1513