An analysis of nystagmus in 100 consecutive patients with communicating syringomyelia

Journal of the neurological Sciences, 1973, 20:381-386

381

© Elsevier Scientific Publishing Company, Amsterdam - Printed in The Netherlands

An Analysis of Nystagmus in 100 Consecutive Patients with Communicating Syringomyelia D. C. T H R U S H AND J. B. FOSTER Regional Neurological Centre, Newcastle General Hospital, Newcastle upon Tyne (Great Britain) (Received 18 June, 1973)

INTRODUCTION

Although nystagmus is a common finding in disorders of the brain stem and cerebellum, it has a poor localizing value and gives little indication of the underlying pathology. For example, in an analysis of 90 patients with neurofibroma of the left auditory nerve, horizontal nystagmus was present in 75 (Dix and Hallpike 1966). In 5 patients it was wholly or predominantly to the left, in 35 wholly or predominantly to the right and in 35 there was first degree symmetrical nystagmus to right and left. During the past 30 years the association of nystagmus with cranio-vertebral anomalies and tumours in the neighbourhood of the foramen magnum has become increasingly well-recognised (List 1941; Cogan and Barrows 1954; Spillane, PaUis and Jones 1957) and this is important if erroneous diagnoses are to be avoided. Dissociated nystagmus, i.e. oscillations of different amplitudes in the 2 eyes or which occur in 2 planes, has been a frequent finding. Characteristically horizontal phasic nystagmus is seen together with vertical nystagmus on upward gaze and ScoviUe and Sherman (1951) stressed the frequency of an atypical coarse type of nystagmus which was present with the eyes in the neutral position and changed character or direction when the gaze was altered. Dissociated nystagmus is also a characteristic feature of posterior fossa lesions which may be secondary to vascular, .neoplastic, degenerative or demyelinating disease (Cogan 1963). Communicating syringomyelia responds to surgical decompression at the foramen magnum if it is recognised before the cervical cord becomes severely damaged. We have therefore studied the abnormal ocular movements in 100 consecutive patients with communicating syringomyelia to determine whether there is a characteristic pattern of nystagrnus which would be of diagnostic value. The majority of the patients formed part of a recent review on syringomyelia (Barnett, Foster and Hudgson 1973). MATERIAL

All the patients were investigated in the Newcastle University Hospital Group at the Regional Neurological Centre or the Royal Victoria Infirmary, between 1965 and

382

D.c.

THRUSH, J. B. FOSTER

1972. The diagnosis of Chiari type 1 malformation, dilatation of the cervical cord and or arachnoiditis was made on myelography in the supine position and in 47 of the cases with tonsillar ectopia it was confirmed at operation.

Definition of terms First degree nystagmus is defined as nystagmus which is present only when the patient looks in the direction of the fast component. Second degree nystagmus is as first degree, with nystagmus which is present, though reduced, in the neutral position. RESULTS

Eighty-six of the 100 patients had communicating syringomyelia secondary to a Chiari malformation. In 14 the signs were secondary to arachnoiditis. Twentythree patients showed nystagmus, 12 males (mean age 32.7 years) and 11 females (mean age 37.3 years). Eighteen of these had a Chiari malformation and in 5 there was demonstrable arachnoiditis.

Chiari patients (a) Horizontal nystaomus. Horizontal phasic nystagmus was found in 7 patients. Two showed unilateral first degree nystagmus, 4 bilateral first degree nystagmus which in 3 was asymmetrical and 1 of these patients also had horizontal nystagmus on upward gaze; 1 patient demonstrated bilateral second degree nystagmus. (b) Vertical nystaomus. One patient showed vertical nystagrnus in all directions of gaze though it was most prominent on downward gaze and another demonstrated vertical nystagmus on gaze to the right, left and downwards. (c) Rotary nystagmus. Rotary nystagmus was evident in 2 patients, who showed bilateral first degree and second degree rotary nystagmus respectively. (d) Horizontal and vertical nystagmus. Five patients had a mixture of horizontal and vertical nystagmus. Bilateral first degree horizontal phasic nystagmus was present in 4 patients and 1 patient exhibited bilateral second degree horizontal phasic nystagmus. Four patients demonstrated vertical nystagrnus on upward gaze and 1 of these also showed vertical nystagmus with the eyes in the neutral position. In 1 patient vertical nystagmus was evident only on downward gaze. (e) Complex nystagmus. In 2 patients the nystagmus was complex, One patient showed coarse horizontal phasic nystagmus with the eyes in the neutral position, coarse bilateral rotary nystagmus on gaze to the right and on gaze to the left the abducting eye displayed rotary nystagmus and the addueting eye vertical nystagmus. The second patient showed ataxic nystagmus associated with rotary nystagmus of the adducting eye and vertical nystagmus on upward gaze.

Arachnoiditis patients (a) Horizontal nysta#mus. In 2 patients there was bilateral first degree phasic nystagmus and 1 patient showed second degree nystagmus to the right. (b) Rotary nystagmus. One patient demonstrated second degree bilateral rotary nystagmus.

NYSTAGMUS W I T H COMMUNICATING SYRINGOMYELIA

383

(c) Horizontal and vertical nystagmus. Bilateral second degree phasic horizontal nystagmus and vertical nystagmus on upward gaze was present in 1 patient. The findings are summarized in Table 1. Nine patients (50~) with Chiari malformations and nystagmus had involvement of other cranial nerves though there was no relationship to the pattern of nystagmus observed. Five patients had oscillopsia and in 2 patients nystagmus was the only neurological abnormality. Fourteen patients with nystagrnus underwent surgical decompression: in 4 the nystagmus disappeared completely (mean time 6.5 months) and none of these had involvement of other cranial nerves. One patient showed considerable improvement. Four further patients showed no essential change in the pattern of nystagrnus (mean follow-up period 4.8 years), and in 2 the nystagmus had increased in degree or changed character. Three patients failed to attend for follow-up appointments though nystagmus was still present in 1 patient 2 years after surgery. One patient died from acute myeloid leukaemia. Four of the 5 patients with arachnoiditis had involvement of other cranial nerves and 1 complained of oscillopsia. Four had surgical explorations and in 2 a ventriculoatrial shunt was inserted. The nystagmus disappeared completely in 1 patient who had had a valve inserted, 1 complained that the oscillopsia was more pronounced and in 2 the nystagmus was unchanged.

DISCUSSION

tn a review of 40 patients with Chiari malformations (Mallis, Cohen and Gross 1951 ) more than 50~o showed nystagmus and an incidence of 62~o was reported in a series of patients with developmental anomalies of the foramen magnum (Spillane et al. 1957). The incidence of nystagmus in our patients, viz. 23~o, is therefore unexpectedly low. No diagnostic pattern of nystagmus was found although 4 8 ~ showed dissociated nystagmus. There was no relationship between the pattern of nystagmus and involvement of the cranial nerves, limbs or degree of descent of the cerebellar tonsils. Ten of the 23 patients with nystagmus had no other cranial nerve signs. We would therefore urge that all patients with unusual nystagmus, providing they have no other features which indicate a specific disorder, be investigated with prone and supine myelography. Cogan (1963) in a review of dissociated nystagmus in posterior fossa lesions stated that with lateralized lesions the homolateral eye showed the greater oscillations. This was not evident in our patients. It has been suggested that a variation in the nystagmus with alteration of posture implies a Chiari malformation (Cogan and Barrows 1954). Although some of our patients demonstrated this phenomenon there was insufficient information on postural testing from which to draw any definite conclusions in this retrospective study. Regrettably our investigations can throw little light on the debatable question as to whether nystagmus can occur with an isolated lesion of the cervical cord. Such a lesion could theoretically cause nystagmus by involving the medial longitudinal fasciculus, the spino-vestibular pathways or the cervical somatic afferent fibres with

TABLE 1

SUMMARY OF PATIENTS WITH ( ' O M M U N I ( ' A I ' I N G

S Y R I N G ( ) M Y F I IA A N D N Y S I A G M I

Sex and aye (years)

Duration of symptoms

Oscillopsia

M46

4mo

-

M 24

6 mo

+

1° R > L

F 51

8mo

+ -

1° R a n d L, greater in a b d u c t i n g eye a n d present on u p w a r d gaze 2° R a n d L 1° to L

F 25 M 27

childhood 1 week

.

.

. . . . horizontal

.

.

.

Nvsta~lmus . . . . tcrtn a/

K

rotary

1° L > R ~

F 49

4 yrs

-

1° t o R

F 50

16 yrs

-

1° R a n d L

F 38

6 yrs

+

F 56

30 yrs

F 19

6mo

M 34

3 yrs

M 34

3 yrs

M 36 M 35 M 24

2 yrs 12 yrs 2 yrs

M 34

all d i r e c t i o n s particularly on d o w n w a r d gaze R and L and d o w n w a r d gaze

1° R a n d L increased b y change of posture 2° R a n d L

m

1° R a n d L

o n u p w a r d gaze

1° R a n d L 1° R a n d L 1° R a n d L

o n u p w a r d gaze 2° on u p w a r d gaze o n d o w n w a r d gaze

1 mo

2° R a n d L

on u p w a r d gaze

F 30

2 yrs

M 30

3 yrs

M 42

4 yrs

-

c o a r s e h o r i z o n t a l n y s t a g m u s a t rest. C o a r s e r o t a r y n y s t a g m u s o n gaze to R. O n gaze to L : a b d u c t i n g eye r o t a r y n y s t a g m u s , a d d u c t i n g eye vertical n y s t a g m u s a t a x i c n y s t a g m u s : a d d u c t i n g eye s h o w e d r o t a r y n y s t a g m o i d jerks. Vertical n y s t a g m u s o n u p w a r d gaze increased b y c h a n g e of posture 2° R a n d L

M 26

2 yrs

+

2° R a n d L

F 32 F 37

4 yrs 16 yrs

F 24

3 yrs

+ + -

1° R a h d L 1o R a n d L 2° t o R

1° : first degree, 2 ° : s e c o n d degree; R : right, L: left. h S y m p t o m s a n d signs confined to c r a n i a l nerves.

o n u p w a r d gaze

Other cranial nerves involved

Myelogram

Operation

tonsillar descent

Feb. 1969

R: trigeminal dissociated sensory loss. R: palatal weakness

normal (prone only)

fibrillation and wasting of tongue

wide canal

July 1964 tonsillar descent + abnormal arch atlas Oct. 1964 tonsillar descent

I

_

tonsillar descent

m

Feb. 1969 June 1966 tonsillar descent Jan. 1968

Progress

3.5 yrs post-op. 1° bilateral phasic n y s t a g m u s with vertical n y s t a g m u s on downward gaze 6 yrs post-op, bilateral coarse 1° rotary nystagmus L > R

died 1965. Acute myeloid leukaemia

8 m o post-op, no n y s t a g m u s

cistema m a g n a not filled

refused

lost from clinic 4.5 yrs post-op, rotary nystagmoid jerks to L lost from clinic

tonsillar descent

refused

moved

complete obstruction L z

unfit

progressively deteriorating

tonsillar descent

April 1968

5 m o post-op, no n y s t a g m u s

L: trigeminal dissociated loss fibrillation R tongue

IV ventricle not filled tonsillar descent

April 1966 tonsillar descent Feb. 1966

fibrillation tongue

tonsillar descent tonsillar descent tonsillar descent

April 1968 Jan. 1968 Nov. 1964

tonsillar descent

April 1969

tonsillar descent

July 1972

2 yrs post-op, no change. Lost from clinic 6.5 yrs post-op, bilateral 2° phasic nystagmus. No change in vertical nystagmus 3 yrs post-op, no change 8 m o post-op, no nystagmus 8 yrs post-op, bilateral 2 ° horizontal phasic nystagmus. No change in vertical nystagmus 3 yrs later bilateral 2 ° horizontal phasic nystagmus. N o vertical nystagmus 4 m o post-op. 2° rotary n y s t a g m u s to L

tonsillar descent

Aug. 1967

4 m o post-op, no n y s t a g m u s

L: trigeminal dissociated sensory loss. L: palatal weakness L: trigeminal dissociated sensory loss

arachnoiditis

June 1967

arachnoiditis

June 1968 valve 1969

fibrillation tongue. Weak neck flexors

arachnoiditis

Aug. 1972

7 mo post-op, dissociated n y s t a g m u s R > L. Moved 4 yrs post-op, bilateral 1° phasic horizontal nystagmus, 2 ° vertical nystagmus on downward gaze. Oscillopsia more pronounced 4 m o post-op, no change

L: trigeminal dissociated sensory impairment dissociated sensory loss. L: maxillary and mandibular distribution. L: palatal weakness. Wasted L tongue dysarthria.

L: facial hypo-aesthesia. Impaired sensation to pin prick. R : maxillary and mandibular distribution

weakness neck flexors

dissociated sensory loss. L: maxillary and mandibular distribution

tonsillar descent

arachnoiditis arachnoiditis

I

valve Nov. 1969

no change 8 yrs post-op, bilateral 2° horizontal phasic nystagmus. N o change in vertical n y s t a g m u s

386

D. C. THRUSH, J. B. FOSTER

which the vestibular apparatus maintain the eyes in a constant relationship with the environment during changes in head position. Biemond (1939, 1940) described 5 patients with brachial neuritis who had severe positional vertigo and nystagmus and positional nystagmus can be induced in the experimental animal by section of the cervical dorsal roots or injection of procaine into the cervical paravertebral tissues (Biemond and de Jong 1969). Furthermore, in an extensive review of spinal cord tumours in the English, French, German and Dutch literature Biemond and de Jong (1969) found 12 patients with cervical tumours and nystagmus. Thus there is established evidence that isolated lesions in the cervical cord can cause nystagmus. We believe the association is rare because such lesions also frequently involve the brain stem or vertebro-basilar vasculature, because positional nystagmus is not always looked for or because in slow progressive lesions compensatory mechanisms may suppress the nystagrnus. The pathogenesis of the nystagmus in patients with communicating syringomyelia remains uncertain but we presume that it is secondary to interference with vestibular pathways, probably in the median longitudinal fasciculus. This would be supported by the high incidence of dissociated nystagmus, the variation with change of posture and the report of 2 patients with Chiari malformations who had an internuclear ophthalmoplegia (Cogan 1970). The nystagmus disappeared in 4 of the 14 patients with Chiari malformations who underwent decompression. This would suggest a vascular pathogenesis, probably secondary to the compression in the region of the foramen magnum. SUMMARY

In a consecutive series of 100 patients with communicating syringomyelia 2 3 ~ had nystagrnus. Dissociated nystagmus was a frequent finding but no pathognomonic pattern was found. The variations in the patterns of nystagmus are described and the importance of not dismissing such patients as untreatable is stressed. REFERENCES BAgNI~'rI', H. J. M., J. B. FOSTERAND P. HUDGSON(1973) Syringomyelia; Saunders, London. BIEMOND,A. (1939) On a new form of experimental positional nystagmus in the rabbit and its clinical value, Proc. Kon.. ned. Akad. Wet., 42: 370--375. BII!MOND, A. (1940) Further observations about the cervical form of positional nystagmus and its anatomical base, Proc. Kon. ned. Akad. Wet., 43: 901-906. BII MOND, A. AND J. M. B. V. DE JONG (1969) On cervical nystagmus and related disorders, Brain, 92: 437-458. COGAN, D. G. (1963) Dissociated nystagmus with lesion in the posterior fossa, Arch. Ophthal., 70: 361-368. COGAN, D. G. (1970) Internuclear ophthalmoplegia--typical and atypical, Arch. Ophthal., 84: 583-589. COGAN, D. G. AND L. J. BARROWS(1954) Platybasia and Arnold Chiari Malformation, Arch. Ophthal., 52 : 13-29. DIx, M. R. AND C. S. HALLPIr~ (1966) Observations on the clinical features and neurological mechanisms of spontaneous nygtagmus resulting from unilateral neurofibroma, Acta oto-laryn9. (Stockh.), 66: 1-22. LlST, C. F. (1941) Neurological syndromes accompanying developmental anomalies of the occipital bone~ atlas and axis, Arch. Neurol. Psychiat. (Chic.), 45: 577-616. MALLIS, L. I., I. COHEN AND S. W. GROSS (1951) Arnold Chiari malformation, Arch. Suro., 63: 783-798. SCOVILLE, W. G. A~D I. J. SnF,~MAN (1951) Platybasia. Report of ten cases with comments on familial tendency; a special diagnostic sign, Ann. Surg., 133 : 496-502. SPILLANE,J. D., C. PALLlSAND A. M. JONES(1957) Developmental anomalies in the region of the foramen magnum, Brain, 80:11-48.