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Show ,. Cli/l. Nt'urll-t1phtllalnllll. 5: 41-44. 1985 Vertical Ocular Motility Disturbance in Pseudotumor Cerebri R. S. BAKER. M.D.. F.R.C.P.(C). F.R.C.S.(C) J. R. BUNClC. M.D.. F.R.C.S.(C) Abstr~ct ThrH patients with pseudotumor cerebri developed transient vertical oculu motor abnormalities. All had associated sixth nerve palsies and two had significant abnormalities of visual acuity and fields. Effective treatment of elevated intracranial pressure nCp) resulted in resolution of the motility disturbance in all cases. This unusual oculomotor feature of elevated ICP may be due to skew deviation or fourth nerve palsy, but in either instance it is not a localizing sign. Pseudotumor cerebri is a diagnosis of exclusion depending. in part. on the absence of localizing signs. Horizontal ocular motility disturbance due to sixth nerve palsy is a frequent occurrence in this s\'ndrome and is well known to be nonlocalizing: ln contrast. abnormalities of vertical ocular motility. in otherwise characteristic pseudotumor cerebri. are uncommon and present the clinical dilemma of false localization. We describe three such cases of transient vertical ocular motor abnormalities in children who were treated at the Hospital for Sick Children in Toronto. Canada. Case Reports Patient 1 A IS-year-old girl was admitted July 13. 1977. with a 3-week history of headache. nausea. and vomiting. Six days prior to admission she experienced diplopia. Abnormalities on physical examination were confined to the visual system. Visual acuity was 20/15 -2 in each eye. There was fully deveillped bilateral papilledema.1"he ocular motility disturbance was complex including both horizontal and From the Dt.'partment of Ophthdlm..lo);y. Th,' 11....plldl f..r Sick Childr..n. Toronto. Canddd. March 1985 vertical components. In primary position she had a 25-prism diopter (PO) esotropia with bilateral lateral rectus weakness. The esotropia decreased in upward gaze (8PO). and increased in downward gaze (35PO); a V-pattern. When the horizontal deviation was neutralized a small. but definite incomitant vertical deviation was present as well: a right hypertropia of 1PO in left gaze. and a left hypertropia of 1PO in right gaze which increased to 2PO in gaze down and right and disappeared in gaze up and right. A Hess screen demonstrated bilateral lateral rectus weakness with a V-pattern and an incomitant vertical deviation (Fig. 1). Head tilt testing was not recorded. The diagnosis of pseudotumor cerebri was supported by normal skull x-rays. CT scan. and metabolic studies. Cerebrospinal fluid (CSF) was obtained at the time of insertion of a Richmond screw for continuous intracranial pressure monitoring. Analysis of the fluid was normal. Pressure waves to 35 mm Hg were recorded during 24 hours of monitoring. After 48 hours of treatment with Oecadron. 2 mg every 4 hours. the ICP stabilized bdow 20 mm Hg. Monitoring was discontinued. Visual acuity after 3 days uf treatment was '10/ 15 in each eye and papilledema was less than on admission. The paralytic esutropia. V-pattern. and hypertropia had all improved. An esutropia of 2PO was seen in all positions l\f gaze except upward where it decreased to 1PO. There was no hypertropia un left gaze. On gaze duwn and right. a 2PO left hypertropia was present which decreased tll half a diopter un gaze right and gaze up and right. Thl' patient was discharged un oral Decadron with a regimen tu taper the dose over 3 weeks. Three weeks after discharge. examination shuwed visual acuity uf 20/15 in each eye. normal ocular motility. and mild residual blurring of the disc margins. No return of symptoms or signs occurred in 2 years of follow-up. 41 I'selld"tllll1l1r Cerebri Green before Ltft E)lt" Figure 1. l\ltJt'nt I II"" ,,'r",'n ,h"w, biLltc'r,ll I,ltc'ral rt'ctu' wl'akn,'" wIth a mJrk,'d mCfl',)'" "f l'Slltrup,a In dllwngaze A sm,lll fight h\'pl'rtrupl" ,n kft g,l/" " ,11,,, dt'm"n,tr,ltc'd Thl' Idt h\'p,'rtrupla In nght gal" I' n"t "\Ident b\' thl" test, but was clt'cul\' prl'~l'nt Q\' pri ....m U.I\'t'T tl' .... t Patient 2 A 5-year-old girl admitted on January 5, 1978, had been well until she developed a right otitis medIa 1 month earlier. Ampicillin was given and the acute otitis resolved, but 1 week after initiation of therapy she developed headache and nausea followed by intermittent diplopia. The only abnormalities noted at admission were bilateral papilledema and lateral rectus weakness. She was seen in neuro-ophthalmologic consultation the day after admission. Visual acuity was 20/25 -2 in'the right eye and 20/25 -1 in the left eye, Bilateral lateral rectus weakness was present, right worse than left. Abduction of the left eye was weaker in depression than in elevation giving an increase in the esotropia in down gaze (V-pattern), On attempted lateral gaze to either side there was nystagmus of the adducting eye, which was more prominent on left than right gaze, Bilateral disc edema was present. Investigations included plain skull films which showed generalized splitting of the sutures, and normal brain scan, CT scan of head and orbits, and vertebral arteriogr,1m, Routine hem,1tology and blood chemistry were normal. Pseudotun1llr cerebri was diagnos'ed and Decadron 4 mg en'n' 8 hours was started, Despite treatment headach~' and diplopia persistl'd, During a weekend pass 2 weeb after admission the patient began to cumplain of difficulty seeing. Examination when she returned rl've,1Ied a visual acuity of 2ll/30 in the right l'Vl' with vision prl'served in only a 1llO centr,ll field, and hand 42 motions onl\' detectable with the left eye. Bilateral lateral rect~s weakness with a V-pattern persisted; in addition, howe\'er, a large left hypertropia was present with relative inability to depress the left eve in any position of gaze. These signs raised suspicion' of posterior fossa pathology missed by the CT scan Carotid angiographY and insertion of a ventricular drain were carried out under a single anesthetic. The arteriogram \\'as normal Ventricular pressure measured ,-13 mm Hg Analysis of the CSF was nllrmal Intracranial pressure was controlled by intermittent drainage of ventricular tluid for 2-1 hours and a lumboperitoneal shunt was then perfl)rmed. Ophthalmoll)gic evaluation 3 weeks after shunting shl)wed visual acuity of 20/30 in the right eve and improvement to 20/-10 in the left eve. Visual fields were markedlY constricted in b'llth eves \\'ith nl) light perception outside the central areas Ocular ml)tility was improved with Slll11l' persistent lateral rectus weakness, but norm, 1l \'ertical movements, Both optic nerveheads \\'l're beginning tll show atrophy and both macul, w ,1ppeared edematous. Fllilow-up Ius been continued for 4 years, A cllmit,1l1t esotropi,1 l)f 10PD was detectable for se\'l'r,11 months, but cl)mpletely normal motility \\\lS reestablished by 1 year. There has been no recurrence of either horizontal or vertical motility disturbance. Despite marked optic atrophy and n1Llderately severe constriction of visual fields, she has rt;tained Snellen 20/20 visual acuity in e,Kh eve. Journal of Clinical Neuro-ophtha!mo!ogy Baker, Buncic Figure :!. I'.11 1l'l1 t 3 H,'" '(f,','11 (,'nllro" tt1l' pf,',en(.. "I bJi~I"f.ll l.ltef~1 ft.'(tu, IV,'""n,,s, ""d a nhhl hvpertrop,a. The nght h\Tl'rtr"f'l,l " 1.1Irh ""n1lt.1I1t 111 up!~.l/" .1lld h,'nll'nt.ll g~Ll', but dl'(fL',"e, in g~Ll' dl'IVn and left. Pa tit'1! t 3 The third patient was a 7-year-old boy who \\'as admitted on January 12, 1972. He was not seen by either of the au'thors, but review of his chart clearly indicates that a transient vertical de\'iation e~isted. He presented with a history of intermittent headaches for several weeks and diplopia for 2 weeks. On admission, he had a visual acuity of 20/70 in each eve and the visual field was constricted to 10° in t'he right eye. Bilateral sixth nerve palsies were present and obvious hypertropia of the right eye was described by the consulting neurologist and ophthalmologist. The deviation was not measured with prisms, However, a Hess screen was obtained (Fig 2), which showed bilateral lateral rectus weakness and a right hypertropia which was comitant in upgaze and horizontal gaze, but decreased in gaze down and left. This vertical component to the motility disturbance caused the clinicians considerable concern regarding the diagnosis, but a thorough search for intracranial mass lesions and metabolic or CSF abnormalities were negative. Pseudotumor cerebri was diagnosed and Decadron 4 mg every 6 hours was started. At discharge 1 week later, the headaches had resolved and the sixth nerve palsies were reduced. The vertical deviation was still present. On follow-up 2 months later, neurosurgical examination documents normal ocular motility and no diplopia, March 1985 Discussion The horizontal ocular deviations of sixth nerve palsy are a familiar nonlocalizing finding in any form of increased ICP and cause no special diagnostic confusion in pseudotumor cerebri. Conversely, vertical deviations are uncommon in this disease and their underlying mechanism is not clear. Either skew deviation or fourth nerve palsy could produce this clinical pattern. The literature contains only a few sparsely detailed examples of cases similar to ours. Keane, in his review of 100 patients with skew deviation, describes only one case that could have been due to pseudotumor cerebri I Details were not given for this case, but he describes the skew deyiation as accompanied by only papilledema. Burger et al. did not describe pseudlltumor as a cause in any of 33 patients with acquired fourth nerye palsy,' but fourth nerve palsy has been reported in association with diffuse raised intracranial pressure.' 4 Merikangas described a case of intermittent vertical deviation in a 35-year-old woman with pseudotumor cerebri.' Ske~v deviation was diagnosed, but no specific characterization of the motility abnormality was given, Resolution of the vertical diplopia accompanied control uf the intracranial pressure. A patient with intermittent vertical diplupia was described by Curbett et al. in a review of 57 pseudotumor ~~atients, but no diplopia or abnormal ocular motility was present at any of the times the patient was examined." 43 In the thret' patients prl'sl'nted here, vt'rtical \lnIlM devi.ltion was pMt of a comp!l'x ocular motility disturbance including bilall'ral sixth nerye p.1Isies. Differenti.1ling bL'lween skew de\' i.ltion .1I1d fourth Iwrve palsy WilS not as str.1ightforw.Hd .1S it would have been with only .1 VL'rtical ckvi.ltion. Our first patient had a left h\'p\'rtnlpi.1 on g.1l.l' right and a right hypertwpia \In g.lIl' left. This p.1tll'rn is typical of bilateral fourth nt'n'l' p.llsv Inerl'ase in the left hypertwpi. l on gall' down and right and no vertical de\' i.lti\ln on gaze up and right is further evidence hI[ fourth nerve palsy as is a V-pattern esotropia. o head tilt was recordt'd, although this would have beL'll helpful in diagnosis. It is possible that this .1llernating hypertropia could be supranuclt'. H reflecting a complt'x skew deviation as describt'd bv Cogan. ~ Also, Nashold and Gills rep\ lrted a skew deviation characterized by a double hvpotrupia differing with gaze to either side produced bv a unilateral stereotactic lesion in the midbrai~ tecta I area. This patient's deviation mimicked overaction of the superior obliques." [n this same report, an A-pattern exotropia was produced by the same lesion indicating that complex strabismus patterns can be caused by supranuclear brain stem disease. A deviation similar to the V-pattern esotropia seen in our patients, but with forced depression and convergence, has been produced by electrical stimulation of the posterior thalamus and caudal mesencephalon in ~ man. The second patient was not cooperative enough for detailed motility measurements with prisms, but inspection revealed persistence of the left hypertropia in either abduction or adduction, suggesting a skew deviation in this instance. In the third patient, the chart clearly documents a significant hypertropia of the right eve. The clinicians who managed this child did not quantitate the deviation with a prism cover test in different positions of gaze, but we can derive some information frum analvsis of the Hess screen. A rather large right hv'pertropia is documented. Fourth nerve palsies tend to give smaller deVIatIons than this. [n gaze right and left the deviation is fairly comitant with the exception of gaze down and left whert' the vertical separation IS mInImal. With an acull' fourth nerve palsy tht' nght hypt'rtropla would be expected to be maximal In the down and lL'ft position We can Cllllelude that the hypertrupia in this case probably represented a skew deviation. Control of l'lt'vatl,(j ICP was accompanied by resolution of thl' motilIty abnormality. The most obvious ocular motor abnormality in tht'se three childrt'n was sixth nen'l' p.Ht'sis. \Ve haw seen Sixth nerve paresis in 29 childrl'n of 60 WIth pseudotumor cerebri, but have rl'Cllgni/ed 44 vertical deviations only three times. Prominent visual sensory abnormalities in two of these cases might suggest that vertical deviations occur in more severe disease, but case I and the case presented by Merikangas' had no visual abnormalities and a very benign course. It would appear that a vertical deviation does not reflect directly the severity of optic neuropathy from elevated [CP, but the vertical deviated does seem to resolve quickly with lowered pressure. Thus, the presence of a vertical deviation may reflect the degree of [CP elevation in a given patient. In cases of severe paralytic esotropia, vertical deviation due either to skew or fourth nerve palsy may be difficult to appreciate clinically. The apparent incidence of three cases in 60 may, therefore, represent only a portion of such misalignments. When found, a vertical deviation may raise the question of brain stem tumor, vascular malformation, or demyelinating disease, In our experience, these latter conditions have been a more frequent cause of vertical motility disturbance than pseudotumor cerebri and they should be considered first. We have demonstrated that vertical ocular motility defects can be a nonlocalizing sign occurring in the setting of otherwise characteristic pseudotumor cerebri The vertical de\'iation is usually seen in conjunction with si:\th nerve palsy and responds rapidh' to effecti\'e treatment of elevated ICP. References 1 Keane, .IR: Ocular ske\\' de\'iatilm: Analvsis of 100 cases Ar,·h ..\·,'lIr,'! 32: 185-1QO, 1975.' , Burger, L.I, Kalnn, \:H, and Smith, JL: Acquired lesi\ms \li the i\lurth cranial nen·e. Brain 93: 56757. t, 1470. 3. Cllbbs, \\' H.. Schatz, ".I and Sa\'ino, PJ: MidbraIn el'e signs In h\'drl1cephalus (Abstract.) Am!. .\'fllnl ! 4: 172. 1478. .t. H.llpern, II. and G\)rdlm, \\·.H, Ir,: Trochlear nen'e pa!s\' as a ialse k)calizing sign. ~~III!. Ophtha/III,,/. 13: 53-5t-, 1481 5 1'. knklllg.lS, I R Skew dena tilm In pseudotumor c'l'r\'bn . .~/III . .\','IIr,l! 4: 583, 1478. b. C\lrbl'tt. 1.1. S.l\Inl), PI, Thl1mpson, S, et al.: \·Isu.ll 1\lsS in ~'seudlltum\lr cerebri. Arch. NeuroJ. 39: .tt-1-.t7.t. 1482 Cllg.m. DG .\'fllr,,/,'gll (If the OCillaI' Mllscles (2nd ed) Ch.Hles C Thl)mas. Springiield, Illinois, 1956, p. 135. 1\. N.lSh,lld. BS.. .md Gills J.R., Jr.: Ocular signs from br,lin stimulation and lesions. Arch. Ophthalmo/, 77: t-lN, 14t-7. q N.lShllld, BS.. and Seaber, J.H.: Defects of ocular m\ltIiit\' .1 iter sterelltactic midbrain lesions in man. A,.d!. t)l'hth,I/lI/ll/. 88: 245-248,1972. . Write t,lr rel'rints to: R. S. Baker, M.D., Department \11 Ophthalmol\lg\', N154 Chandler Medical Center, /lOO R\ISe Street, Le'\ington, Kentucky 40536. Journal of Clinical Neuro-ophthalmology |
