Neurochirurgia 18 (1975), 109-112 © Georg Thieme Verlag Stuttgart
Stenosis of the Aqueduct of Sylvius by a Heterotopic Island of Grey Matter O. Vuia
Summary The present paper reports on the case of a one-year old child with a clinical picture of noncommunicating hydrocephalus. The anatomical examination revealed stenosis of the aqueduct of Sylvius produced by an heterotopic island of grey matter. The pathogenetic data concerning this form of stenosis of the aqueduct of Sylvius, not yet described before, are discussed. Key words: hydrocephalus - aqueduct of Sylvius - gliosis heterotopia of the grey matter
Zusammenfassung Die Arbeit berichtet über den Fall eines einjährigen Kindes mit dem klinischen Bild eines nichtkommunizierenden Hydrozephalus. Die anatomische Untersuchung wies eine Stenose des Aquaeductus Sylvii nach, hervorgerufen durch eine Heterotopie der grauen Substanz. Die pathogenetischen Grundlagen, die diese Form der Stenose des Aquaeductus Sylvii betreffen und die bisher noch nicht beschrieben wurden, werden besprochen.
Résumé Sténose de l'aqueduc de Sylvius du fait d'un îlot hétérotopique de matière grise. Ce travail porte sur le cas d'un enfant d'un an affichant le tableau clinique d'une hydrocéphalie non communicante. L'examen anatomique montra une sténose de l'aqueduc de Sylvius causée par une hétérotopie de matière grise. On épilogue sur les bases pathogéniques de cette forme de sténose non encore décrite jusqu'à ce jour.
Since Dandy (1921) described atresia and stenosis of t h e a q u e d u c t of Sylvius as a possible cause of the so-called idiopathic h y d r o -
cephalus, n u m e r o u s f u n d a m e n t a l a n a t o m i c a l studies have been published regarding this condition {Globus a n d Bergmann 1946; Lichtenstein 1959; Russell 1949; Zülch and Nachtwey 1958). As described in t h e neurological literature, atresia and stenosis of the a q u e d u c t of Sylvius may be congenital (stenosis, forking of the aqueduct, septum formation) Norman 1963) or acquired. Between these t w o forms a p p e a r s the closure of t h e Sylvian aqueduct by a b n o r m a l gliosis in t h e surr o u n d i n g tissue: such gliosis of the a q u e d u c t may occur in Recklinghausen's disease as a manifestation of a d e v e l o p m e n t a l dysplasia, or may be acquired following an intraventricular infection (Zülch and Nachtwey 1958; Norman 1 9 6 3 ; Mathes 1969). T h e pathogenesis of congenital stenosis of the a q u e d u c t is still, however, very obscure. T h e present p a p e r r e p o r t s o n a case t h a t reveals n o t only an u n k n o w n aspect of the p a t h o l o g y of stenosis of t h e a q u e d u c t of Sylvius b u t also m a k e s a c o n t r i b u t i o n t o its pathogenesis. Case 57/74, W. J. K. boy, born 14 Nov. 1973 of healthy parents. Since birth a manifest hydrocephalus was observed for which a Raymondi drainage was applied. On 31 July 1974 he was admitted to the Pediatric Clinic on account of massive hydrocephalus and frequent vomiting. On 1 August a cardio-respiratory syncope developed. Resuscitation accompanied by intraventricular puncture was successful, but two days later the child died with phenomena of cardiac syncope preceded by bradycardia. Pathological anatomy: no pathologic alterations were noted in the viscera apart from generalized stasis. Central nervous system. The major lesions were located in the brain, the cross section of
Downloaded by: NYU. Copyrighted material.
Institute of Neuropathology, Justus Liebig University, Giessen, West Germany
O. Vuia
which showed hydrocephalus with signs of drainage of the left lateral ventricle. At the level of the midbrain the aqueduct of Sylvius was completely absent and replaced by a grey, sharply delimited mass (Fig. 1). This aspect was noted from the origin up to the end of the aqueduct of Sylvius (serial sections). In the other formations of the brain stem no changes were noted at the gross examination, apart from slight cerebellar herniation around the medulla with discrete dilatation of the 4th ventricle. The microscopic examination (hematoxylineosin, Nissl staining) showed that the aqueduct of Sylvius was completely closed except for a small, marginal portion with a very narrowed lumen. The entire aqueduct was lying horizontally, appearing to be pushed downwards by a heterotopic formation made up of apparently nor-
Fig. 1: Mid-brain. On gross examination the aqueduct of Sylvius appears to be completely obstructed. Note the clearly delimited grey formation that has developed in its place (arrows).
mal nerve cells. Above this formation, the structure of the nuclei of the colliculus superior and inferior exhibited no aberrations, the rest of an ependymal canal being found between these formations and the heterotopic grey matter island indicating the normal course of the aqueduct of Sylvius. Below the narrowed and compressed aqueduct, the position and structure of the oculomotor nuclei and other mid-brain formations were normal (Figs 2 and 3). At a larger magnification the nucleus interposed along the normal course of the aqueduct of Sylvius was found to be made up of morphologically mature nerve cells (Fig. 4). The same lack of abnormal features was noted in the quadrigeminal and oculomotor nuclei. N o microscopic alterations were found in the rest of the central nervous system. Diagnosis. Hydrocephalus produced by stenosis of the aqueduct of Sylvius whose normal course appeared to be replaced by a heterotopic island of grey matter.
Fig. 2: The aqueduct of Sylvius (AS) lies horizontally and is obstructed except for a small lateral portion. Along the normal course of the aqueduct a grey formation can be seen, formed of nerve cells, that appears to be separated upwards from the nuclei of the colliculus superior (c) by traces of the ependymal canal (EC). Interiorly the narrowed aqueduct of Sylvius separates this formation from the oculomotor nuclei (Nissl, x 4).
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110
Stenosis of the Aqueduct of Sylvius by a Heterotopic Island and Grey Matter
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Interpretation and discussion. In the present case stenosis of the aqueduct of Sylvius was produced by a heterotopic island of grey matter which, by developing in the place of the aqueduct displaced it downwards and horizontally, obstructing it. The traces of ependymal canal found above the heterotopic mass demonstrate moreover that the heterotopic island of grey matter had developed at the site of the aqueduct. This appearance has not previously been described. In a single case, communicated by Lichtenstein (1959), the author found the aqueduct of Sylvius separated into two segments and narrowed by the medial nucleus of the common oculomotor nucleus. Globus and Bergman (1946) found juvenile nerve cells with a lymphocytic character around the partially obstructed Sylvian aqueduct. In neither of these cases however is there question of a heterotopic nucleus of grey matter lying along the course of the sylvian canal as in our case. The latter may be asserted to be a case of heterotopic island of grey matter since it has not direct connexion either with the nuclei of the quadrigeminal bodies lying above it or with the oculomotor nuclei lying below it and from which it is separated by the stenosed, obstructed aqueduct of Sylvius. Pathogenetically, the origin of this heterotopia of grey matter must be regarded as a malformation, in early embryonic life. Em-
bryogenesis shows that originally the aqueduct of Sylvius is much larger, accompanying the physiologic hydrocephalus of the fetal brain up to the age of four months (Duncan and Hild 1968). It must therefore be admitted that with development of the grey and white
•
* :
-
. . . .
•••
•
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.
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"
¿Ä***^*"-' Fig. 4: The hterotopic island of grey matter is formed of morphologically matute nerve cells (Nissl, x 20).
Downloaded by: NYU. Copyrighted material.
Fig. 3: The aqueduct of Sylvius, displaced and obstructed with heterotopic island of grey matter above it (Nissl, x 10).
O. Vuia
formations of the midbrain (alar and basal lamina) the aqueduct is grac'.ually narrowed reaching the size it has in the maturely developed brain. In this situation, the normal formation of the aqueduct of Sylvius is directly connected with the activity of the periventricular matrix, from which arise, by an migration towards the periphery, first the neuronal and then the glial formations, and locally the ependymal epithelium. In our case the teratogenic factor acted upon this periventricular matrix, preventing neuronal migration and thus giving rise to an heterotopic island of grey matter which developed in the place of the aqueduct of Sylvius, pushing it downwards and narrowing it. The fact that the heterotopic island is formed of nerve cells with a morphologically mature aspect corresponds to the general structure of hetero-
topias of the grey matter, more frequently encountered however in the white matter of the cerebral hemispheres. In order to produce this type of malformation a developmental dysplasia factor must interfere at a very early embryonic stage when migration of the nervous elements from the periventricular matrix takes place. As a rule the malformative factors act much later, only affecting the development of the glial system, explaining why in most cases development of the aqueduct is arrested by gliosis, as in Recklinghausen's disease in which its dysplastic nature is so evident. Our case may be considered as a rare instance of stenosis of the aqueduct of Sylvius, and of particular interest as regards its mode of production.
Bibliography 1 2
3
4
Dandy, W. E.: T h e cause of so-called idiopathic hydrocephalus. Bull. J o h n s H o p k . H o s p . 32 (1921) 67 Duncan, D., W. Hild: Embryogenesis of the nervous system. In Pathology of the nervous system. Ed by Minkler M c Graw-Hill Book C o m p a n y , N e w York 1968 p. 77 Globus, J. H., Ph. Bergman: Atres a and stenosis of the aqueduct of Sylvius. J. N e u r o p a t h . & Exp. Neurology 5 (1946) 342 Ijcbtenstein, B. W.: Atresia and stenosis of the aqueduct of Sylvius. J. of N e u r o p a t h , and E x p . Neurology 18 (1959) 3 Dr. O . Vuia, Zentrum
für Neurologie
Abtlg.
5
Mathes, A.: Hydrocephalus internus. In: H a n d b . der Kinderheilkunde. Springer Berlin, Heidelberg, N e w York 1969 VIII/1, p . 148
6
Norman, R. M.: Aqueductal malformation leading to hydrocephalus. In: Greenfield's N e u r o p a t h o l o g y . Ed. Arnold Publ. L o n d o n (1963) p . 342
7
Russell, D. S.: Observations on the pathology of hydrocephalus. Spec. R e p . Ser. med. Res. C o u n . (Lond.) 1949 Nr 265
8
Ziilch, K. J., W. Nachtwey: Pathologie u n d Klinik des Aquäduktverschlusses. Z b l . Neurochir. 18 (1958) 80
Neuropath* ilogie der Justus-Liebig-Universität,
63 Gießen,
Arndtstraße
16
Downloaded by: NYU. Copyrighted material.
112
Stenosis of the Aqueduct of Sylvius by a Heterotopic Island of Grey Matter O. Vuia
Summary The present paper reports on the case of a one-year old child with a clinical picture of noncommunicating hydrocephalus. The anatomical examination revealed stenosis of the aqueduct of Sylvius produced by an heterotopic island of grey matter. The pathogenetic data concerning this form of stenosis of the aqueduct of Sylvius, not yet described before, are discussed. Key words: hydrocephalus - aqueduct of Sylvius - gliosis heterotopia of the grey matter
Zusammenfassung Die Arbeit berichtet über den Fall eines einjährigen Kindes mit dem klinischen Bild eines nichtkommunizierenden Hydrozephalus. Die anatomische Untersuchung wies eine Stenose des Aquaeductus Sylvii nach, hervorgerufen durch eine Heterotopie der grauen Substanz. Die pathogenetischen Grundlagen, die diese Form der Stenose des Aquaeductus Sylvii betreffen und die bisher noch nicht beschrieben wurden, werden besprochen.
Résumé Sténose de l'aqueduc de Sylvius du fait d'un îlot hétérotopique de matière grise. Ce travail porte sur le cas d'un enfant d'un an affichant le tableau clinique d'une hydrocéphalie non communicante. L'examen anatomique montra une sténose de l'aqueduc de Sylvius causée par une hétérotopie de matière grise. On épilogue sur les bases pathogéniques de cette forme de sténose non encore décrite jusqu'à ce jour.
Since Dandy (1921) described atresia and stenosis of t h e a q u e d u c t of Sylvius as a possible cause of the so-called idiopathic h y d r o -
cephalus, n u m e r o u s f u n d a m e n t a l a n a t o m i c a l studies have been published regarding this condition {Globus a n d Bergmann 1946; Lichtenstein 1959; Russell 1949; Zülch and Nachtwey 1958). As described in t h e neurological literature, atresia and stenosis of the a q u e d u c t of Sylvius may be congenital (stenosis, forking of the aqueduct, septum formation) Norman 1963) or acquired. Between these t w o forms a p p e a r s the closure of t h e Sylvian aqueduct by a b n o r m a l gliosis in t h e surr o u n d i n g tissue: such gliosis of the a q u e d u c t may occur in Recklinghausen's disease as a manifestation of a d e v e l o p m e n t a l dysplasia, or may be acquired following an intraventricular infection (Zülch and Nachtwey 1958; Norman 1 9 6 3 ; Mathes 1969). T h e pathogenesis of congenital stenosis of the a q u e d u c t is still, however, very obscure. T h e present p a p e r r e p o r t s o n a case t h a t reveals n o t only an u n k n o w n aspect of the p a t h o l o g y of stenosis of t h e a q u e d u c t of Sylvius b u t also m a k e s a c o n t r i b u t i o n t o its pathogenesis. Case 57/74, W. J. K. boy, born 14 Nov. 1973 of healthy parents. Since birth a manifest hydrocephalus was observed for which a Raymondi drainage was applied. On 31 July 1974 he was admitted to the Pediatric Clinic on account of massive hydrocephalus and frequent vomiting. On 1 August a cardio-respiratory syncope developed. Resuscitation accompanied by intraventricular puncture was successful, but two days later the child died with phenomena of cardiac syncope preceded by bradycardia. Pathological anatomy: no pathologic alterations were noted in the viscera apart from generalized stasis. Central nervous system. The major lesions were located in the brain, the cross section of
Downloaded by: NYU. Copyrighted material.
Institute of Neuropathology, Justus Liebig University, Giessen, West Germany
O. Vuia
which showed hydrocephalus with signs of drainage of the left lateral ventricle. At the level of the midbrain the aqueduct of Sylvius was completely absent and replaced by a grey, sharply delimited mass (Fig. 1). This aspect was noted from the origin up to the end of the aqueduct of Sylvius (serial sections). In the other formations of the brain stem no changes were noted at the gross examination, apart from slight cerebellar herniation around the medulla with discrete dilatation of the 4th ventricle. The microscopic examination (hematoxylineosin, Nissl staining) showed that the aqueduct of Sylvius was completely closed except for a small, marginal portion with a very narrowed lumen. The entire aqueduct was lying horizontally, appearing to be pushed downwards by a heterotopic formation made up of apparently nor-
Fig. 1: Mid-brain. On gross examination the aqueduct of Sylvius appears to be completely obstructed. Note the clearly delimited grey formation that has developed in its place (arrows).
mal nerve cells. Above this formation, the structure of the nuclei of the colliculus superior and inferior exhibited no aberrations, the rest of an ependymal canal being found between these formations and the heterotopic grey matter island indicating the normal course of the aqueduct of Sylvius. Below the narrowed and compressed aqueduct, the position and structure of the oculomotor nuclei and other mid-brain formations were normal (Figs 2 and 3). At a larger magnification the nucleus interposed along the normal course of the aqueduct of Sylvius was found to be made up of morphologically mature nerve cells (Fig. 4). The same lack of abnormal features was noted in the quadrigeminal and oculomotor nuclei. N o microscopic alterations were found in the rest of the central nervous system. Diagnosis. Hydrocephalus produced by stenosis of the aqueduct of Sylvius whose normal course appeared to be replaced by a heterotopic island of grey matter.
Fig. 2: The aqueduct of Sylvius (AS) lies horizontally and is obstructed except for a small lateral portion. Along the normal course of the aqueduct a grey formation can be seen, formed of nerve cells, that appears to be separated upwards from the nuclei of the colliculus superior (c) by traces of the ependymal canal (EC). Interiorly the narrowed aqueduct of Sylvius separates this formation from the oculomotor nuclei (Nissl, x 4).
Downloaded by: NYU. Copyrighted material.
110
Stenosis of the Aqueduct of Sylvius by a Heterotopic Island and Grey Matter
HI
¿&£^W.,,
^
^
^
^
i
»
^
^
^
=
*
-
*
*
v
^
'
••
-•
••
'
•••'
' ' ? • * ' •
Interpretation and discussion. In the present case stenosis of the aqueduct of Sylvius was produced by a heterotopic island of grey matter which, by developing in the place of the aqueduct displaced it downwards and horizontally, obstructing it. The traces of ependymal canal found above the heterotopic mass demonstrate moreover that the heterotopic island of grey matter had developed at the site of the aqueduct. This appearance has not previously been described. In a single case, communicated by Lichtenstein (1959), the author found the aqueduct of Sylvius separated into two segments and narrowed by the medial nucleus of the common oculomotor nucleus. Globus and Bergman (1946) found juvenile nerve cells with a lymphocytic character around the partially obstructed Sylvian aqueduct. In neither of these cases however is there question of a heterotopic nucleus of grey matter lying along the course of the sylvian canal as in our case. The latter may be asserted to be a case of heterotopic island of grey matter since it has not direct connexion either with the nuclei of the quadrigeminal bodies lying above it or with the oculomotor nuclei lying below it and from which it is separated by the stenosed, obstructed aqueduct of Sylvius. Pathogenetically, the origin of this heterotopia of grey matter must be regarded as a malformation, in early embryonic life. Em-
bryogenesis shows that originally the aqueduct of Sylvius is much larger, accompanying the physiologic hydrocephalus of the fetal brain up to the age of four months (Duncan and Hild 1968). It must therefore be admitted that with development of the grey and white
•
* :
-
. . . .
•••
•
-
.
>
"
¿Ä***^*"-' Fig. 4: The hterotopic island of grey matter is formed of morphologically matute nerve cells (Nissl, x 20).
Downloaded by: NYU. Copyrighted material.
Fig. 3: The aqueduct of Sylvius, displaced and obstructed with heterotopic island of grey matter above it (Nissl, x 10).
O. Vuia
formations of the midbrain (alar and basal lamina) the aqueduct is grac'.ually narrowed reaching the size it has in the maturely developed brain. In this situation, the normal formation of the aqueduct of Sylvius is directly connected with the activity of the periventricular matrix, from which arise, by an migration towards the periphery, first the neuronal and then the glial formations, and locally the ependymal epithelium. In our case the teratogenic factor acted upon this periventricular matrix, preventing neuronal migration and thus giving rise to an heterotopic island of grey matter which developed in the place of the aqueduct of Sylvius, pushing it downwards and narrowing it. The fact that the heterotopic island is formed of nerve cells with a morphologically mature aspect corresponds to the general structure of hetero-
topias of the grey matter, more frequently encountered however in the white matter of the cerebral hemispheres. In order to produce this type of malformation a developmental dysplasia factor must interfere at a very early embryonic stage when migration of the nervous elements from the periventricular matrix takes place. As a rule the malformative factors act much later, only affecting the development of the glial system, explaining why in most cases development of the aqueduct is arrested by gliosis, as in Recklinghausen's disease in which its dysplastic nature is so evident. Our case may be considered as a rare instance of stenosis of the aqueduct of Sylvius, and of particular interest as regards its mode of production.
Bibliography 1 2
3
4
Dandy, W. E.: T h e cause of so-called idiopathic hydrocephalus. Bull. J o h n s H o p k . H o s p . 32 (1921) 67 Duncan, D., W. Hild: Embryogenesis of the nervous system. In Pathology of the nervous system. Ed by Minkler M c Graw-Hill Book C o m p a n y , N e w York 1968 p. 77 Globus, J. H., Ph. Bergman: Atres a and stenosis of the aqueduct of Sylvius. J. N e u r o p a t h . & Exp. Neurology 5 (1946) 342 Ijcbtenstein, B. W.: Atresia and stenosis of the aqueduct of Sylvius. J. of N e u r o p a t h , and E x p . Neurology 18 (1959) 3 Dr. O . Vuia, Zentrum
für Neurologie
Abtlg.
5
Mathes, A.: Hydrocephalus internus. In: H a n d b . der Kinderheilkunde. Springer Berlin, Heidelberg, N e w York 1969 VIII/1, p . 148
6
Norman, R. M.: Aqueductal malformation leading to hydrocephalus. In: Greenfield's N e u r o p a t h o l o g y . Ed. Arnold Publ. L o n d o n (1963) p . 342
7
Russell, D. S.: Observations on the pathology of hydrocephalus. Spec. R e p . Ser. med. Res. C o u n . (Lond.) 1949 Nr 265
8
Ziilch, K. J., W. Nachtwey: Pathologie u n d Klinik des Aquäduktverschlusses. Z b l . Neurochir. 18 (1958) 80
Neuropath* ilogie der Justus-Liebig-Universität,
63 Gießen,
Arndtstraße
16
Downloaded by: NYU. Copyrighted material.
112
