Abducens nerve palsy as initial symptom of trigeminal

Joutrnal ofNeurology, Neurosurgery, and Psychiatry, 1977, 40, 1190-1197

Abducens nerve palsy as initial symptom oftrigeminal schwannomaJUNKOH YAMASHITA, RENIN ASATO, HAJIME HANDA,SATOSHI NAKAO, AND MASAHIRO OGATA

From the Departments of Neurosurgery, Kyoto University Medical School, Kyoto, and KobeMunicipal Central Hospital, Kobe, Japan

SUMMARY The insidious onset and slow progression of symptoms may cause delay in therecognition of trigeminal schwannomas. Two cases with abducens nerve palsy as an initialsymptom are reported, in both of whom the tumour was growing mainly below and anterior tothe intracavernous portion of the internal carotid artery. Early detection of clinical symptomsand thorough radiological investigations are important in the early diagnosis of these lesions.

Schwannomas of the trigeminal nerve are raretumours. They usually present pains or sensoryloss of the face as initial symptoms. Cases withouttrigeminal involvement have been reported oc-casionally (Jefferson, 1955; Olive and Svien, 1957;Knudsen and Kolze, 1972; Arseni et al., 1975).Disturbances of extraocular movements are fre-quently observed as a minor concomitant symptomin the advanced stage of trigeminal schwannomas,as the result of cavernous sinus compression.However, this is rarely seen as an initial symptom.Recent experience of two such unusual cases withabducens nerve palsy as an initial and predominantsymptom prompted us to report them and to eluci-date its diagnostic and therapeutic importance.

Case reports

CASE 1This 38 year old man was admitted to Kyoto Uni-versity Hospital on 12 March 1976, complainingof double vision which he had first noted on rightlateral gaze while driving about 10 months previ-ously. The symptom was gradually progressive,and he consulted a hospital where it was pointedout that he had right abducens nerve palsy. Hewas referred to our hospital with the clinicaldiagnosis of parasellar tumour. His past medical

Address for reprint requests: Professor H. Handa, Department ofNeurosurgery, Kyoto University Medical School. 54 Kawahara-cho,Sakyoku, Kyoto, Japan 606.Accepted 12 July 1977

history and family history were non-contributory.Examination on admission was within normal

limits except for right abducens nerve palsy. Sen-sation of the face and corneal reflex were intact.There were no cerebellar signs or signs of in-creased intracranial pressure. Plain skull radio-graphs showed no deformity of the sella turcica.There was no bony destruction in the middlecranial fossa and pyramis. Right carotid angio-graphy (Fig. 1) showed the intracavernous portionof the internal carotid artery displaced medially,superiorly and posteriorly. There was a tumourstain of fingertip size in the parasellar region inthe late arterial and capillary phases of the lateralprojection. Retrograde jugular venography dis-closed a shadow defect in the anterolateral portionof the right cavernous sinus. Pneumoencephalo-graphy showed a slight dilatation and elevationof the right temporal horn of the lateralventricle.On 24 March 1976, a right temporal craniotomy

was carried out in the left lateral position. Whenthe temporal lobe was elevated through the intra-dural approach, an extradural mass was seen inthe medial portion of the middle cranial fossa.The tumour was well demarcated and vascular.It was incompletely removed, leaving a small por-tion adhering to the medial structures. Nervefibres in the extradural space under the tumourwere thought to be the first division of the tri-geminal nerve. His postoperative course was un-eventful but an area of hypaesthesia persisted inthe region supplied by the first and second

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Abdutcens nerve palsy as initial symptom of trigeminal schwannoma

Fig. 1 Case 1. Right carotid angiography showing intracavernous portion of internal carotid artery displacedmedially, superiorly and posteriorly. There is a tumour stain in the parasellar region (arrow).

branches of the trigeminal nerve and the rightcorneal reflex was absent. Abducens nerve palsywas much improved postoperatively. Histologicaldiagnosis was reported to be a schwannoma (Fig.2). When he was seen in the outpatient clinic eightmonths later, right abducens nerve palsy had dis-appeared completely, although the disturbance offacial sensation and corneal reflex persisted. Hehad returned to his previous occupation and wasable to drive a car.

CASE 2This 27 year old man was admitted to KobeMunicipal Central Hospital on 9 October 1974,complaining of double vision. He was well untilfive days before admission when headache, nausea,and vomiting developed acutely without loss ofconsciousness while playing mah-jong. The nextday he woke up with double vision on left lateralgaze. Symptoms other than diplopia had graduallysubsided in a few days. His past medical andfamily histories were non-contributory.

Examination on admission showed that he wasalert and orientated. General physical and neuro-logical examinations showed no abnormalitiesexcept left abducens nerve palsy. Corneal reflexand facial sensation were intact. There were nocerebellar signs or signs of increased intracranialpressure. On the eighth and tenth hospital dayshe experienced two episodes of acute exacerbationof headache, nausea, and vomiting. On each oc-casion the degree of left abducens palsy becameeven worse. Around the 20th hospital day, thepatient noted for the first time decreased sensationto pinprick and touch in the region supplied bythe first division of the left trigeminal nerve.The routine laboratory examinations were all

within normal limits. Spinal tap performed on thethird hospital day showed the initial pressure110 mmH2O and the closing pressure 90 mmH2O.Cerebrospinal fluid appeared watery clear: itsprotein content was 0.33 g/l and there was nopleocytosis. Skull radiographs showed a slightenlargement of the left foramen ovale. Left

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Fig. 2 Photomicrograph showing schwannoma (case 1). HE X200.

carotid angiography (Fig. 3) showed the intra-cavernous portion of the internal carotid arterydisplaced medially, superiorly and posteriorly.There was a tumour stain of fingertip size in theregion of the cavernous sinus in the lateral pro-jection. Retrograde jugular venography showed afilling defect in the anterolateral portion of theleft cavernous sinus, corresponding to the site ofthe tumour stain on angiography.A left temporal craniotomy was carried out on

28 November 1974. The lesion was approachedintradurally. On elevating the temporal lobe, anextradural tumour was found at the site of theforamen ovale. The tumour was elastic soft, welldemarcated, and vascular. No evidence of recentintratumoural haemorrhage was confirmed duringoperation. The tumour was incompletely removed,leaving a portion adhering to the first division ofthe trigeminal nerve.

Postoperatively, left abducens nerve palsy wastemporarily worsened, and there was sensory lossin the region supplied by the first and seconddivisions of the trigeminal nerve. Histologicaldiagnosis was schwannoma (Fig. 4). The patientreceived a course of postoperative irradiation.When he was seen two months after the comple-tion of irradiation, left abducens nerve palsy haddisappeared and the only neurological abnormalitywas sensory dullness in the region supplied by thefirst division of the left trigeminal nerve.

Discussion

The incidence of trigeminal schwannomas re-ported by various authors ranged between 0.07and 0.33% of all intracranial tumours (Schisanoand Olivecrona, 1960; Arseni et al., 1975). In theDepartment of Neurosurgery, Kyoto UniversityMedical School, nine cases of trigeminal schwan-nomas were recorded among 2491 intracranial tu-mours in the period of 36 years from 1941 to 1976inclusive (0.36%). Among 10 cases including onefrom Kobe Municipal Central Hospital reportedas case 2 above, five were men and five women.The age varied from 24 to 43 years with anaverage of 33.4 years. The clinical data of these10 cases are summarised in the Table.

Jefferson (1955) classified trigeminal schwan-nomas into three groups: (1) in the middlecranial fossa, (2) in the posterior cranial fossa,and (3) in both middle and posterior cranial fossae.Symptoms vary depending on the anatomicallocalisation of the tumour. The different clinicalmanifestations have been analysed extensively inthe literature. Since our two cases are of tri-geminal schwannomas in the middle cranial fossa,our discussion will focus mainly on this variety.

In more than half the cases reported, facial painor facial numbness was the initial and predomi-nant clinical symptom. Krayenbuhl (1936), in hisstudy of trigeminal schwannomas, emphasised that

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Abdcuens nerve pals.y as initial svmptom of trigeminal schwannoma

w w. -;.Fig. 3 Case 2. Left carotid angiography showing intracavernous portion of internal carotid artery displacedmedially, superiorly and posteriorly. There is a tumour stain in the parasellar region (arrow).

intense facial pain is in favour of a tumour in themiddle cranial fossa starting from the Gasserianganglion, whereas a tumour of the trigeminal rootin the posterior cranial fossa is often unaccom-panied by pain. This observation was confirmed bySchisano and Olivecrona (1960). None of theirfour patients with schwannomas of the trigeminalroot suffered from pain, whereas five out of 11cases with schwannomas of the Gasserian ganglionexperienced facial pain. In our series, however,only one out of five cases with schwannomas ofthe Gasserian ganglion suffered from pain, andnone of those in the posterior fossa or in bothfossae experienced facial pain. In our opinion thepresence of facial pain does not appear to beimportant in tumour localisation. Arseni et al.(1975) also expressed the same opinion regardingfacial pain.Our two cases had abducens nerve palsy as an

initial and predominant symptom while trigeminalsymptomatology was absent (case 1) or slight(case 2). We could find only three similar casesamong 53 cases from the available literature-namely, case 3 and case 9 of Schisano and Olive-crona's series (1960), and Gordy's case (1965). It iswell known that some cases of trigeminal schwan-nomas have no facial pain or numbness (Jefferson,1955; Olive and Svien, 1957; Knudsen and Kolze,1972; Arseni et al., 1975). Jefferson (1955) explainsthe absence of, or mild, trigeminal symptomat-ology by the fact that the schwannoma involvesonly part of the nerve fibres, and the tumour in itssubsequent development does not affect the rootof the nerve.The oculomotor nerve is rarely affected even if

the cavernous sinus is compressed by these tu-mours. According to Jefferson (1955), this is instrong contrast with malignant invasions of the

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Fig. 4 Photomicrograph showing schwannomna(case 2). HE X400.

ganglion or secondary deposits which frequentlyproduce total ophthalmoplegia. Among the cranialnerves controlling the extraocular movements, allof which run through the cavernous sinus, theabducens nerve is the most vulnerable to com-

pression by schwannomas of the Gasserianganglion. The reason is that it takes its course

between the intracavernous portion of the internalcarotid artery and the Gasserian ganglion in thelower portion of the cavernous sinus, whereas thethird and fourth cranial nerves take their courses

more superiorly, away from the trigeminal nerve

(Fig. 5). The common feature in our two cases

was that abducens nerve palsy had brought thepatient to the hospital in the early stage of theillness. Trigeminal schwannoma should be in-cluded in the list of aetiological factors in thedifferential diagnosis of unilateral abducens nerve

palsy. Occasionally the tumour may grow un-

noticed to a considerable size, as in case 6 ofOlive and Svien's series (1957), where an asympto-matic schwannoma 25X25X20 mm was found inthe Gasserian ganglion at necropsy of a patientwho died of Hodgkin's disease.

Radiological investigations are extremely im-portant in the early diagnosis of trigeminalschwannomas (Palacios and MacGee, 1972;Miyagami et al., 1974; Levinthal and Bentson,1976). The most constant findings on plain skullfilms are destruction of the petrous apex and en-largement of the foramina ovale and rotundum(Basauri and Asenjo, 1967). However, all thesefindings are late signs and were not conspicuousin our two cases. Characteristic changes may bedemonstrated by angiography. The intracavernousportion of the internal carotid artery is in mostcases displayed anteriorly, medially, and inferiorly(Westberg, 1963; Glasauer and Tandon, 1969;

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Fig. 5 Diagram sketch of intracavernous portion of internal carotid artery. The third andfourth nerves run above and the fifth and sixth below triangular space outlined in the dottedline. Redrawn from Parkinson (1965).

Wullenweber et al., 1976). In both of our cases,however, the intracavernous portion was displacedmedially, superiorly and posteriorly, indicatingthat the tumour was growing mainly below andanterior to the internal carotid artery. We believethat the direction of tumour growth is closelyrelated to the early manifestation of abducensnerve palsy. Similar angiographic changes weredescribed in case 3 of Westberg's series (1963)but without clinical details. Angiography was notperformed in case 3 of Schisano and Olivecrona'sseries (1960). It was performed but not fully des-cribed in case 9 of Schisano and Olivecrona'sseries (1960). Angiography in Gordy's case (1965)revealed straightening and elevation of the carotidsyphon with an irregular, feathery vascular stainin the medial temporal region. A similar tumourstain was seen in both of our cases. These patho-logical vessels may represent actual tumour vesselsor enlargement of the branches of the artery ofthe inferior cavernous sinus. Retrograde jugularvenography may provide important informationon cavernous involvement with the tumour.

Pneumoencephalography revealed a slight eleva-tion of the temporal horn in case 1 reported above.This procedure, however, will certainly be re-placed to some extent by computerised tomo-graphic scanning in the future.Schwannomas in the middle cranial fossa can

be excised through a temporal craniotomy. Weprefer an intradural approach to obtain a betterexposure. Total removal of the tumour is thetreatment of choice, although great care isnecessary to avoid damage to the cranial nervesand the internal carotid artery in the cavernoussinus. We had to content ourselves with incompleteremoval in both cases. Fortunately, however, thelong-term result of partial removal is reported tobe rather good (Schisano and Olivecrona, 1960;Northfield, 1973).

References

Arseni, C., Dumitrescu, L., and Constantinescu, A.(1975). Neurinomas of the trigeminal nerve. Surgi-cal Neurology, 4, 497-503.

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Abducens nerve palsy as initial symptom of trigeminal schwannoma

Basauri, L., and Asenjo. A. (1967). Trigeminal neur-inomas. A cta Neurochlirurgica. 17, 1-6.

Glasauer, F. E., and Tandon. P. N. (1969). Trigeminalneurinomas in adolescents. Journal of Neurology,Neurosurgery, and Psychiatry. 32, 562-568.

Gordy, P. D. (1965). Neurinoma of the Gasserianganglion. Report of a case and review of theliterature. Journal of Neurosurgery, 22, 90-94.

Jefferson, G. (1955). The trigeminal neurinomaswith some remarks on malignant invasion of theGasserian ganglion. Clinical Neurosurgery, 1,11-54.

Knudsen, V., and Kolze, V. (1972). Neurinoma of theGasserian ganglion and the trigeminal root. ActaNeurochirurgica, 26, 159-164.

Krayenbuhl. H. (1936). Primary tumours of the rootof the fifth cranial nerve: their distinction fromtumours of the Gasserian ganglion. Brain, 59, 337-352.

Levinthal, R., and Bentson, J. R. (1976). Detection ofsmall trigeminal neurinomas. Journal of Neuro-surgery. 45, 568-575.

Miyagami, M., Goto, T., Sugawara, T., Tsubokawa,T., and Moriyasu, N. (1974). Trigeminal neurinoma:

ganglion type and root type. Neurological Surgery,2, 63-70). (In Japanese.)

Northfield, D. W. C. (1973). The Surgery of theCentral Nervous System. Blackwell Scientific Puibli-cations: Oxford.

Olive, I., and Svien, H. J. (1957). Neurofibromas ofthe fifth cranial nerve. Journal of Neurosurgery,14, 484-505.

Palacios, E., and MacGee. E. E. (1972). The radio-graphic diagnosis of trigeminal neurinomas. Journalof Neurosurgery, 36, 153-156.

Parkinson, D. (1965). A surgical approach to the cav-ernous portion of the carotid artery: anatomicalstudies and case report. Journal of Neurosurgery,23, 474-483.

Schisano, G., and Olivecrona, H. (1960). Neurinomasof the Gasserian ganglion and trigeminal root.Journal of Neurosurgery. 17, 306-322.

Westberg, G. (1963). Angiographic changes inneurinoma of the trigeminal nerve. Acta Radio-logica Diagnostica. 1, 513-520.

Wullenweber, R., Traupe, H., and Schwarz, G. (1976).Angiographic demonstration of a trigeminalneurinoma. Neuroradiology. 10, 225-229.

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Abducens nerve palsy as initial symptom of trigeminal