Journal of Neurology, Neurosurgery, and Psychiatry, 1972, 35, 776-788 Tumours of the third ventricle in children BENNETT M. STEIN, RICHARD A. R. FRASER, AND MICHAEL S. TENNER From the Department of Neurological Surgery, Tufts-New England Medical Center, Boston, and Department of Radiology, Neurological Institute, New York, U.S.A. SUMMARY Experience with 25 cases of tumour of the third ventricle in children is reviewed. The majority of the lesions were infiltrating astrocytomas of the anterior and mid-portions of the third ventricle. These tumours were generally inoperable. However, other tumours within the third ventricle were benign, encapsulated, and resectable. Surgical exposure was carried out through one of three routes: posterior fossa, transcallosal, or subfrontal. The radiological criteria by which the operative approach is determined are discussed. In children, if one excludes craniopharyngiomas, primary tumours of the third ventricle are un- common. In a series of 100 childhood brain tumours (Walker and Hopple, 1949), 15 tumours were located in the third ventricle. Pecker, Ferrand, and Javalet (1966) reported nine child- hood tumours of the third ventricle out of 35 cases. Almost all of the tumours in the children were astrocytomas. Cuneo and Rand (1952) observed that 15% of astrocytomas in children are located in the third ventricle, which was con- sidered a favourite site for supratentorial tumours. Most surgeons have considered these tumours to be inoperable; accordingly a shunt- ing procedure followed by radiotherapy has been the treatment of choice (Torkildsen, 1948; Ward and Spurling, 1948; Rand and Lemmen, 1953; Cummins, Taveras, and Schlesinger, 1960). Twenty-five of our cases of third ventricular tumour in children seen in the past four years are reviewed. Although the astrocytoma pre- dominated, a variety of other tumours occurred in this region and in some cases, because of encapsulation, were amenable to surgery. The route of surgical approach was determined by radiographic features of the tumour. We have categorized these lesions as follows: (1) posterior or pineal region; (2) centro-anterior or thalamic and foramen of Monro region; (3) inferior or hypothalamic-chiasmatic region. Six illustrative cases of the 25 are presented. 776 CASE 1 R.Z., a 2 year old male, was admitted in 1967 with markedly increased intracranial pressure, right hemi- paresis, and severe dehydration from persistent vomiting. A ventriculogram showed a large third ventricular mass with a rounded contour (Fig. 1). Because of the state of the patient a ventriculopleural shunt was carried out from both lateral ventricles. This markedly improved his condition; the focal neurological findings gradually resolved and a radiotherapy course of 5,000 r was directed to the tumour. Four months later repeat ventriculography revealed no evidence of tumour (Fig. 1). The shunts were removed and he remains well four years after treatment. CASE 2 S.M., a 4 month old male, was admitted in 1967 with a bulging anterior fontanelle, 'sunset' displacement of the eyes, and bilateral optic atrophy. Ventriculo- graphy showed a large mass filling the anterior third ventricle and obstructing the foramina of Monro. Air was noted in this cystic mass outlining its diaphenous wall (Fig. 2). Using a transcortical approach, an ependymal cyst was removed from the third ventricle. Post- operatively the child continued to manifest signs of raised intracranial pressure and a pneumoencephalo- gram showed evidence of an incisural block. A ventriculoatrial shunt relieved this problem. The child has been followed for four years and, apart from mental retardation, is well. Protected by copyright. on March 23, 2020 by guest. http://jnnp.bmj.com/ J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.35.6.776 on 1 December 1972. Downloaded from
Transcript
Journal of Neurology, Neurosurgery, and Psychiatry, 1972, 35, 776-788
Tumours of the third ventricle in childrenBENNETT M. STEIN, RICHARD A. R. FRASER,
AND MICHAEL S. TENNER
From the Department of Neurological Surgery, Tufts-New England Medical Center, Boston,and Department of Radiology, Neurological Institute, New York, U.S.A.
SUMMARY Experience with 25 cases of tumour of the third ventricle in children is reviewed. Themajority of the lesions were infiltrating astrocytomas of the anterior and mid-portions of the thirdventricle. These tumours were generally inoperable. However, other tumours within the third ventriclewere benign, encapsulated, and resectable. Surgical exposure was carried out through one of threeroutes: posterior fossa, transcallosal, or subfrontal. The radiological criteria by which the operativeapproach is determined are discussed.
In children, if one excludes craniopharyngiomas,primary tumours of the third ventricle are un-common. In a series of 100 childhood braintumours (Walker and Hopple, 1949), 15 tumourswere located in the third ventricle. Pecker,Ferrand, and Javalet (1966) reported nine child-hood tumours of the third ventricle out of 35cases. Almost all of the tumours in the childrenwere astrocytomas. Cuneo and Rand (1952)observed that 15% of astrocytomas in childrenare located in the third ventricle, which was con-sidered a favourite site for supratentorialtumours. Most surgeons have considered thesetumours to be inoperable; accordingly a shunt-ing procedure followed by radiotherapy has beenthe treatment of choice (Torkildsen, 1948;Ward and Spurling, 1948; Rand and Lemmen,1953; Cummins, Taveras, and Schlesinger,1960).
Twenty-five of our cases of third ventriculartumour in children seen in the past four yearsare reviewed. Although the astrocytoma pre-dominated, a variety of other tumours occurredin this region and in some cases, because ofencapsulation, were amenable to surgery. Theroute of surgical approach was determined byradiographic features of the tumour. We havecategorized these lesions as follows: (1) posterioror pineal region; (2) centro-anterior or thalamicand foramen of Monro region; (3) inferior orhypothalamic-chiasmatic region.
Six illustrative cases of the 25 are presented.776
CASE 1
R.Z., a 2 year old male, was admitted in 1967 withmarkedly increased intracranial pressure, right hemi-paresis, and severe dehydration from persistentvomiting. A ventriculogram showed a large thirdventricular mass with a rounded contour (Fig. 1).Because of the state of the patient a ventriculopleuralshunt was carried out from both lateral ventricles.This markedly improved his condition; the focalneurological findings gradually resolved and aradiotherapy course of 5,000 r was directed to thetumour. Four months later repeat ventriculographyrevealed no evidence of tumour (Fig. 1). The shuntswere removed and he remains well four years aftertreatment.
CASE 2
S.M., a 4 month old male, was admitted in 1967 witha bulging anterior fontanelle, 'sunset' displacementof the eyes, and bilateral optic atrophy. Ventriculo-graphy showed a large mass filling the anterior thirdventricle and obstructing the foramina of Monro.Air was noted in this cystic mass outlining itsdiaphenous wall (Fig. 2).
Using a transcortical approach, an ependymalcyst was removed from the third ventricle. Post-operatively the child continued to manifest signs ofraised intracranial pressure and a pneumoencephalo-gram showed evidence of an incisural block. Aventriculoatrial shunt relieved this problem. Thechild has been followed for four years and, apartfrom mental retardation, is well.
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FIG. 1. Case 1. (a) Ventriculogram showing tumour filling the third ventricle and encroaching on the bodiesandfrontal horns of lateral ventricles (arrows). (b) Pneumoencephalogram post radiation showing regression oftumour and outline of air in the third ventricle (arrow).
(3)1 lr)
FIG. 2. Case 2. (a) Ventriculogram showing mass obstructing the foramina of Monro (arrows). (b) Pneumo-encephalogram showing air which has entered third ventricular cyst separatedfrom air within the third ventricle(dorsal) by the membranous wall of the cyst (arrows).
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8Bennett M. Stein, Richard A. R. Fraser, and Michael S. Tenner
FIG. 3. Case 4. Ventriculogram showing tumour mass partially filling third ventricle. Extent oftumour indicated by arrows.
FIG. 4. Case 4. Coronal section of the brain demon-strating continued growth of tumour compared withextent observed at ventriculography (Fig. 3).
CASE 3
P.C., a 21 year old male, was admitted in 1969 withan enlarging head and loss of vision, associated withoptic atrophy and nystagmus. A ventriculogramrevealed a large mass in the third ventricle. Througha frontal burr hole a needle was passed into the massunder x-ray control. It was not cystic and no tissuewas obtained for examination. The child underwenta ventriculojugular shunt and received 5,000 r ofradiotherapy.
Apart from optic atrophy, the child has remainedwell, although we have no objective indication of theeffect of radiation on this tumour of unidentifiedhistology.
CASE 4
S.T., a 2- year old female, was admitted in 1969with tremor, ataxia, and signs of raised intracranialpressure. A ventriculogram showed a large mass inthe region of the anterior third ventricle whichappeared to arise from the right thalamus (Fig. 3).
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FIG. 5. Case 5. Combin7ed ventriculogram-pneumo-encephalogram showing large third ventricular tumourobstructing foramina of Monro and producingdemineralization of the posterior clinoids and dorsumsellae and displacement of interpedunicular air(arrows).
The lesion was approached via a transcallosalexposure. A large infiltrating mass arising from theright side of the third ventricle was encountered.Biopsy disclosed an astrocytoma, grade II. Aventriculojugular shunt was installed. The childreceived a radiotherapy course of 5,000 r; however,the tumour continued to enlarge and she died 10months later. The necropsy showed a large solidastrocytoma of the third ventricle and right thalamicregions (Fig. 4).
CASE 5
E.G., an 11 year old female, was admitted in 1968with findings of raised intracranial pressure, withoutlocalizing features. Radiographs of the skull showeda deformity of the upper portion of the clivus andlocalized erosion of the dorsum sellae (Fig. 5). Abrachial arteriogram showed lateral displacement ofthe posterior communicating artery and hvdro-cephalus, indicating an interpeduncular mass. Aventriculogram showed a large mass arising from theinferior portion of the third ventricle and extendinginto the interpeduncular space (Fig. 5). The lesionwas explored via a subtemporal exposure on theright side (Fig. 6). An infiltrating exophytic astro-cytoma of the hypothalamus was confirmed by
biopsy and the patient received 5,000 r radiationpostoperatively. She has remained well three yearslater.
CASE 6
K.L., an 11 year old female, was admitted in 1968with mild ataxia, loss of upward gaze and of con-vergence of the eyes, and signs of raised intracranialpressure. A ventriculogram showed a large smoothmass in the posterior aspect of the third ventricleand pineal region (Fig. 7).By a posterior fossa supracerebellar approach the
region was exposed with the successful removal of anepidermoid tumour. The patient has remainedneurologically normal.
DISCUSSION
Little attention has been devoted to the subjectof tumours of the third ventricle in paediatricneurosurgical texts. However, extensive dis-cussion may be found pertaining to lesionsadjacent to this area such as craniopharyn-giomas, pineal tumours, and hypothalamicgliomas (Jackson and Thompson, 1959; Matson,1969). For the purpose of this report we haveincluded pineal and hypothalamic-chiasmatictumours as well as tumours arising directlywithin the third ventricle. Craniopharyngiomaswere excluded, since they are rarely situatedwholly within the third ventricle (van den Berghand Brucher, 1970).Dandy (1933) reported 16 tumours within the
third ventricle. Most of these were classified as ofglial origin, although a few cysts were included.Bailey, Buchanan, and Bucy (1939), under theclassification of optic chiasm gliomas, reported10 tumours all of which were astrocytomas. Theexperience of others writing on this subject issimilar (Smith and Fincher, 1942; French, 1948;Odom, Davies, and Woodhall, 1956; Ford,1966; Pecker et al., 1966; Lakke, 1969). It is,therefore, apparent that most tumours intrinsicto the third ventricle are astrocytomas, usually oflow grade and arising from the diencephalon,hypothalamus, or optic chiasm. A small pro-portion of tumours in this region are ependymalcysts or colloid cysts (Buchsbaum and Colton,1967).Tumours arising in the pineal region often fill
a large part of the third ventricle and, since theymay invade this structure, should not be con-
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Bennett M. Stein, Richard A. R. Fraser, and Michael S. Tenner
FIG. 6. Case 5. Subtemporal exposure of tumour (arrows) which is crossed by the oculomotornerve (white structure) and bounded on the left by the carotid artery.
FIG. 7. Case 6. Ventriculogram showing distortion of posterior portion of a dilated thirdventricle (arrows) by a pineal epidermoid.
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sidered purely as extra-axial masses (Rand andLemmen, 1953; Stein, 1971).The symptoms produced by these tumours
vary somewhat according to their position(Weisenburg, 1911; Critchley, 1925; Dandy,1933). More posterior tumours produce a mid-brain or quadrigeminal plate syndrome whileantero-inferior tumours are commonly associatedwith visual defects and signs of deranged hypo-thalamic function. It is not our intention toreview the symptoms and signs, except to notethat all of these tumours have in common thepropensity to produce obstruction of cerebro-spinal fluid flow early in their growth. This facthas relevance in their surgical management.
RADIOGRAPHIC FINDINGS In the plain radio-graphs of the skull there are few findings whichare diagnostic of this group of tumours. Cal-cification, which occurs frequently in pineal
tumours, is occasionally seen in cholesteatomasbut is rare in the gliomas of this region (Camp,1950). Oligodendrogliomas which have a highrate of calcification are rare in this age group andwhen present tend to involve the septum pelluci-dum and cerebral white matter. Because of theexophytic nature of some of these tumours, localerosive changes of the skull may be seen in theregion of the clivus, dorsum sellae (Fig. 5),anterior and posterior clinoid processes, andtuberculum sellae. These changes are usuallyassociated with gliomas of the chiasm or hypo-thalamus. Lesions which extend further an-teriorly may erode the sphenoid wings or floorof the anterior fossa. Because of the proximity ofthird ventricular tumours to areas of the ven-tricular system readily susceptible to obstruction(foramina of Monro, posterior third ventricleand aqueduct), radiological changes of general-ized increased intracranial pressure or hydro-
FIG. 8. Right brachial arteriogram lateral view. The carotid siphon is slightly open. The distalbasilar artery is displaced backwards. There is separation and slight posterior displacement ofthe perforating thalamic vessels (arrow). The anterior choroidal artery is elevated and straight-ened (arrowheads). The pericallosal artery is elevated, indicating lateral ventricular enlargement.
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Bennett M. Stein, Richard A. R. Fraser, and Michael S. Tenner
cephalus are common. These include: sutureseparation, cephalomegaly, ballooning of thesella turcica, and enlargement of the emissaryvenous channels.Although pneumoencephalography or ven-
triculography has been the mainstay of diagnosisof these lesions, we have found that angiographyis the best initial method of contrast study. Theinformation obtained by angiography will oftenreflect the degree of hydrocephalus, will excludevascular lesions such as aneurysms, malforma-tion of the vein of Galen, and chiasmal arterio-venous malformation, and in the majority ofpatients will localize the lesion and give someclue as to the pathology.
Changes found in the antero-inferior group oflesions (Cassinari and Bernasconi, 1963) arelateral displacement of the distal part of the
internal carotid artery, elevation of the hori-zontal portion of the anterior cerebral arteries,and reversal of the curves of the anterior chor-oidal and posterior communicating arteries,although the reverse curves may solely reflect anenlarged third ventricle. The thalamoperforatevessels originating from the posterior communi-cating artery and tip of the basilar artery will befound to be posteriorly displaced or fixed andseparated (Fig. 8). Changes on the venous sideare primarily reflected by local upward dis-placement of the septal vein and the anteriorportion of the internal cerebral vein (Potts andTaveras, 1963). Larger tumours will displacelaterally the uncal vein and basal vein ofRosenthal.The lesions of the mid-anterior third ventricu-
lar area are characterized by elevation andattenuation of the internal cerebral vein in
FIG. 9. Right brachial arteriogram, venous phase, lateral view. Elevation and attenuation oftheinternal cerebral vein from the region of the entrance of the thalamostriate vein posteriorly forapproximately 1J5 cm (arrow).
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association with hydrocephalic changes (Fig. 9).Unless these lesions are very large, there may belittle else to make the diagnosis. Large lesionswill crowd together the thalamoperforate arteries,and if there is sufficient lateral extension, dis-place the posterior cerebral arteries and basalveins of Rosenthal laterally and inferiorly.
Angiographic changes in the posterior groupof tumours of the third ventricle are diagnosticin the majority of cases. When the lesions arerelatively small the changes in the arterial phasemay be confined to deformity of the medialbranch of the posterior choroidal artery which isdisplaced upwards. As the lesion increases insize, other arterial structures are displaced asthey pass around the posterior portion of themidbrain. This includes the posterior cerebralartery and, with infratentorial extension of thetumour, the superior cerebellar arteries. Charac-
teristically, these tumours deform the posteriorportion of the internal cerebral vein and the veinof Galen (Fig. 10). The majority cause local up-ward displacement of the vein, although occas-ionally the tumour may grow in a horseshoefashion and cause a paradoxical downward dis-placement of the vein. As the lesion extendsinfratentorially, the precentral cerebellar vein isdisplaced backwards and the basal vein ofRosenthal displaced laterally.Pneumoencephalography in the antero-inferior
group of tumours will show deformity of therecesses of the anterior portion of the thirdventricle. Air in the suprasellar and inter-peduncular cisterns will further outline the extentof the lesion. Although the majority of theselesions are astrocytomas, the differential diagno-sis includes cysts, dermoids, cholesteatomas, andother congenital tumours, as well as the rare non-
FIG. 10. Right brachial arteriogram, venous phase, lateral view. The posterior portion of theinternal cerebral vein and the vein of Galen are elevated by a calcified pineal mass (arrows).
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Bennett M. Stein, Richard A. R. Fraser, and Michael S. Tenner
FIG. 11. Retraction offalx (left) and rightcerebral hemisphere exposing the cingulategyrus (arrow) before transcallosal approachto the third ventricle.
calcified craniopharyngioma. The difficulty ofdifferentiating intra-axial and extra-axial lesionsis compounded by the propensity of astrocytomasin this area to be exophytic, in part, and thusmimic extra-axial lesions.
Satisfactory demonstration of centro-anteriorlesions is obtained through air studies. Occasion-ally both pneumoencephalography and ven-triculography must be done in combination. Asmooth rounded contour of the lesion shouldnot convey the impression of a cyst, for many
such lesions are solid (Figs 3 and 7).In patients with posterior lesions, pneumo-
encephalography shows a characteristic de-formity of the posterior portion of the thirdventricle (Fig. 7). Air in the quadrigeminal
cisterns outlines the postero-inferior extensionof the lesion to best advantage. Again, in thisgroup of lesions there is frequently a need forboth ventriculography and lumbar pneumo-encephalography to give complete delineation ofthe lesion and to provide differentiation fromextra-axial lesions arising from the apex of thetentorium.
SURGERY On the basis of radiological and, to alesser extent, the clinical findings, one of threepossible surgical approaches was used in theexploration of these tumours (Table).For lesions of the posterior third ventricle or
pineal region, an exposure through the posteriorfossa was used (Stein, 1971). This operation, first
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reported by Krause (1926), is made between thesuperior surface of the cerebellum and thetentorium. Such an approach has been used forseven pineal lesions without morbidity ormortality.
In only two of these cases, an atypical tera-toma and a low-grade astrocytoma, was thetumour invasive. The remaining five casesrepresented the following pathology: epidermoid,cystic arachnoiditis, and three teratomas, whichwere encapsulated. In four of these cases asignificant portion of the tumour was removedand the patients improved. Six of the seven casesremain alive and well six months to four yearsafter surgery.
For lesions located about the anterior orforamen of Monro region of the third ventricleeither a transcallosal or transfrontal cortexapproach has been used. The former was used infive cases and the latter in six cases. The trans-callosal approach is preferred because theoperator has access to both lateral ventricles aswell as the third ventricle through the foraminaof Monro.
This operation is done with the patient in thesemi-upright position. By decompressing the
ventricular system the corpus callosum may beexposed by retracting the non-dominant hemi-sphere from the falx cerebri (Fig. 1 1); theexposure being centred at the coronal suture(Dandy, 1933). Division of the corpus callosumis usually made between the anterior cerebralarteries (Fig. 12). Upon entering the ventricularsystem the only difficulty that may be encounteredis distinguishing one lateral ventricle from theother. However, with attention to the details ofthe ependymal venous pattern and the course andposition of the choroid plexus this differentiationmay be made easily. In cases operated on by thisroute, little more than a biopsy could be accom-plished, since all of the lesions were non-cysticof infiltrating low-grade astrocytoma type. Noependymomas were encountered.By the standard transfrontal exposure an
incision is made anterior to the coronal suturethrough the middle frontal gyrus and theanterior position of the frontal horn is entered(Dandy, 1933). Unlike the transcallosal ap-proach, exposure of the opposite ventricle,ventral portions of the third ventricle, and thebody of the ipsilateral lateral ventricle is difficult.The six lesions approached by this route repre-
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FIG. 12. Drawing of transcallosal exposure of a third ventricular tumour. The right cerebralhemisphere is being retractedfrom the falx after sectioning an anterior cortical vein.
sented a variety of pathology. In three casesinfiltrating astrocytomas were encountered andlittle more than biopsy was accomplished. In onecase diffuse ventricular seeding from a malignanttumour, probably of pineal origin, was encoun-tered. This was similar to the cases described byFord (1966). In one case an ependymal cystattached to the infundibular region of the thirdventricle was removed and in another a largehaematoma, a complication of diffuse arteritis,was removed from the foramen of Monro region.Of these 11 cases five are dead and the re-
mainder alive two to four years after surgery.A final series of five cases with tumours which
arose primarily in the inferior portion or hypo-thalamic-chiasmatic region of the third ventriclewere approached by the standard subfrontal or,in one instance, a subtemporal route. The latter
procedure was used because of radiographicevidence of an exophytic hypothalamic tumourwhich displaced the posterior communicatingartery and grooved the dorsum sellae. In accord-ance with previous experience, most of thesetumours were low-grade astrocytomas whichwere infiltrating and non-resectable. One ofthese tumours was an exophytic teratoma of thethird ventricle and another, an astrocytoma, con-tained a huge cyst which extended subfrontally.All of the children are alive one to four yearsafter operation and radiotherapy, but three areimpaired.
In one instance (case 1) because of a criticalstate on admission the child underwent a shunt-ing procedure followed by radiotherapy, withouthistological confirmation of the type of tumour.A follow-up pneumoencephalogram after com-
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pletion of radiotherapy showed complete dis-appearance of the tumour. The conclusion wasthat this was a highly radiosensitive tumour,perhaps an ependymoma.
In one child (case 3) the radiographic appear-ance of a smooth-walled mass in the centralportion of the third ventricle was so suggestive ofa cyst that a needle was placed in the central partof the tumour via a frontal burr hole. Obtainingno fluid, the assumption was made that this wasa solid tumour, most likely an astrocytoma. Ashunting procedure was done followed by radio-therapy. Both of these children are well two andthree years respectively after surgery. Neitherhas a confirmed histological diagnosis.
This experience has led to the conclusion thata high proportion of anterior and inferiorlyplaced masses within the third ventricle are low-grade infiltrating astrocytomas. Such was thecase in 11 of 16 confirmed tumours. The remain-ing five were as follows: two organized haema-tomas presenting as masses, one malignantpresumed pineal tumour, one cyst, and oneteratoma.
All of these tumour cases received post-operative radiotherapy. Although follow-upencephalograms were done in only a few in-stances, when performed there was evidence oflittle change in the size of the astrocytomas. Theclinical course of the astrocytoma cases alsowould suggest that radiotherapy did not materi-ally effect the tumour.
In the case of the posterior third ventricular orpineal tumours such heterogeneous pathology isencountered that these tumours should not beregarded with the same pessimism as are othertumours within the third ventricle. This isprobably due in the strictest sense to their extra-ventricular origin. Therefore in the case oftumours of the posterior third ventricle, the sur-geon may reasonably expect to accomplish morethan just a biopsy (Stein, 1971), while in otherthird ventricular tumours biopsy alone is theusual procedure and little can be done to alterthe otherwise dismal outlook of the infiltratingtumours; even by the installation of shunts anduse of radiotherapy.
CONCLUSIONS
Our experience with tumours of the third
ventricle has been reviewed. Three operativeexposures including posterior fossa, transcallosal,and subfrontal are used to expose these lesions.The vast majority of anterior and inferiorly
situated third ventricular tumours representinfiltrating slow growing astrocytomas which arenot amenable to surgical removal and whichrespond poorly to radiotherapy.Tumours of the posterior third ventricle are
occasionally encapsulated and can be removedsurgically.
Because of the possibility of cystic or resectablelesions in the face of an otherwise limited outlookwe recommend surgical exposure and histo-logical confirmation of all tumours within thethird ventricle.
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