J Neurosurg 51:397-401, 1979
Sphenoethmoidal meningoencephalocele associated with agenesis of corpus callosum and median cleft lip and palate Case report
KATSUAKI SAKODA, M.D., SUSUMU ISHIKAWA, M.D., TOHRU UOZUMI, M.D., KATSUHIRO HIRAKAWA, M.D., HIDEO OKAZAKI, M.D., AND YASUO HARADA, M.D. Departments of Neurosurgery and Oto-Rhino-Laryngology, School of Medicine, Hiroshima University, Hiroshima, Japan A case of sphenoethmoidal meningoencephalocele associated with agenesis of the corpus callosum and median cleft lip and palate in a baby boy is reported. Two other cases have been reported previously presenting exactly the same findings. It is possible that these malformations constitute a distinct type of congenital anomaly. KEY WORDS sphenoethmoidal meningoencephalocele median cleft lip 9 median cleft palate 9
C
ASES with basal meningoencephalocele are rare and few cases have been reported. Recently, we encountered a case of sphenoethmoidal meningoencephalocele, one of the types of basal meningoencephalocele, associated with median cleft lip and palate and agenesis of corpus callosum. This case is presented together with a review of the literature. Case Report This baby boy was born on November 10, 1976. His mother's last menstrual cycle began on February 6, 1976. She received an injection of 17-hydroxyprogesterone caproate for vaginal bleeding that was noticed on March 31. At the same time, she took meclizine hydrochloride, 75 mg daily for 14 days, because of severe emesis. She caught cold on September 30, but otherwise her subsequent course was uneventful. No family history of congenital anomalies could be elicited. The patient was delivered normally at full term and birth weight was 2650 gm. Immediately after birth, median cleft lip and palate were noted. Plastic surgery of the median cleft lip was J. Neurosurg. / Volume51 / September, 1979
9 agenesis of corpus callosum
performed uneventfully at another hospital on April 22, 1977. On June 28, 1978, he underwent surgery for cleft palate at the Department of Oto-RhinoLaryngology, Hiroshima University School of Medicine. During the course of the operation, a soft mass was noticed for the first time to te proiect ing into the oral cavity at the site of the nasal septum. Needle aspiration of the mass revealed clear fluid, and he was referred to the Department of Neurosurgery with the suspicion of meningocele. The head circumference was 47 cm. The bregmatic fontanel was completely closed. No abnormalities of the skull and spine were noted on inspection and palpation. The interpupillary distance was 5.0 cm, but hypertelorism was not grossly apparent (Fig. 1). Surgical wounds were noted in the upper lip and median portion of the palate, but no bulging of the mass into the oral cavity was observed. As the right nasal cavity was almost completely occluded by the mass, the patient had to open his mouth slightly to breathe, but there was no respiratory distress. There were no findings indicative of retardation in mental and physical development. 397
K. Sakoda, et al.
Flc. 1. The interpupillary distance is 5.0 cm,
but
hypertelorism is not grossly apparent. Median cleft lip has been surgically repaired.
Tomography revealed a defect, 2.0 cm wide, anterior to the sella turcica, and a mass that filled the nasal cavity. The bone defect was narrow at the front, and the mass was localized at the nasal septum. Computerized tomography (CT) revealed a bone defect located anterior to the sella turcica in the middle of the anterior fossa, and a bone-like bridge which delineated the posterior margin of the defect (Fig. 3). The anterior horns were separated, the posterior horn of the lateral ventricles was dilated, and the third ventricle was deformed and dilated, probably due to agenesis of the corpus callosum. 1~ On the basis of these findings, the case was considered to be sphenoethmoidal meningoencephalocele associated with agenesis of the corpus callosum and median cleft palate and lip. As there was no leakage of cerebrospinal fluid (CSF) nor significant respiratory symptoms, it was decided not to perform radical surgery, but to conduct strict follow-up observation. Discussion
The anteroposterior projection of a plain skull film showed that the interorbital distance was 3.2 cm; an oval-shaped density, 3.0 • 1.4 cm in size, could be seen extending down into the nasal cavity. On the lateral view, the bone defect and the mass could not be clearly observed. The basal view of the skull showed a well circumscribed bone defect with pyramidal-shaped anterior and hemicircular-shaped posterior portions located anterior to the sella turcica (Fig. 2).
It has been said that the incidence of basal meningoencephalocele is one in 35,000 births, 15 but reported cases are very rare. According to Ingraham and Matson 6 among a total of 546 cases of meningocele in the central nervous system, there were 84 cases with meningoencephalocele, of which one was of the transethmoidal type. However, in Japan, only one case of transethmoidal type has been reported among a total of 33 cases of meningoencephalocele. 1
F~. 2. Radiograph, basal view, of the skull. A sharply circumscribed defect can be clearly observed through the anterior skull base.
meningoencephalocele at the sphenoethmoidal region. The bridge of bone is well shown at the site oflimbus sphenoidale (arrow).
398
FIG. 3. Computerized
tomography
scan
reveals
J. Neurosurg. / Volume 51 / September, 1979
Sphenoethmoidal
meningoencephalocele
When a location in the cranial vault is excluded, meningoencephalocele can be grouped into sincipital and basal types. The sincipital type is described in detail by Suwanwela and Suwanwela. 13The basal type may be further subgrouped into transethmoidal, sphenoethmoidal, transsphenoidal, spheno-orbital, and sphenomaxillary types, depending on the site of the bone defect and extension of the mass (Fig. 4)? .1113 The bone defect in the transsphenoidal type is found in the sphenoid bone, particularly at the base of the sella turcica. Eleven cases of this type have been reported in the literature. 7.8,1~,15.x~ In the sphenoethmoidal type, the mass extends into the nasal cavity through the bone defect between the ethmoid and sphenoid bones; our case falls into this category. Although the sphenoethmoidal type is classified as a type of basal meningoencephalocele, review of the literature failed to produce any cases designated as such. The reason is considered to be due to difficulty in differentiating between the sphenoethmoidal and transsphenoidal types on the basis of x-ray examination and surgery. In our case, it was possible to detect a bone bridge on the CT scan. An essential point in establishing the diagnosis of sphenoethmoidal meningoencephalocele is the location of this bridge of bone at the site of limbus sphenoidale (Fig. 5). Two additional cases which could also be considered sphenoethmoidal were found among cases classified as transsphenoidal: the single case reported by Lewin and Shuster? and Case III of Pollock, et al. ~2 (Table 1). In describing their case, Lewin and Shuster stated, "X-ray film of the skull showed a defect in the anterior sphenoid region and a defect posterior to the cribriform plate," which is considered to meet the definition established for sphenoethmoidal
FK~. 4. Sites of bone defect in the cases of sincipital (1) and basal (2-5) meningoencephalocele. 2 = transethmoidal type; 3 - sphenoethmoidal type; 4 - transsphenoidal type (sphenopharyngeal type); 5 = spheno-orbital type.
type. Pollock, et al., described their Case III as follows: "On roentgenologic examination, a large osseous defect was seen in the sphenoid and posterior ethmoid, and a 2 • 3.5 cm osseous defect in the midline extended from posterior clinoids to within 1 cm of the posterior margin of the cribriform plate." It is difficult from the description to establish that the latter case was sphenoethmoidal. However, large transsphenoidal defects are commonly accompanied by hypothalamic dysfunction, hypopJtuitarism, and visual loss, 1' and as their case app~orently failed to demonstrate such evidence, we believe that it could well be interpreted as sphenoethmoidal. The descrip-
FIG. 5. Diagrams comparing transsphenoidal type (right) with sphenoethmoidal type (left). J. Neurosurg. / Volume51 / September, 1979
399
K. Sakoda, et al. TABLE 1 Summary of reported cases of sphenoethmoidal meningoencephalocele Clinical Features
Case 1 (Lewin & Shuster, 1965)
Case 3 (present case)
age sex hypertelorism median cleft lip
15 mos male striking central triangular defect
16 mos male mild present
19 mos male unnoticed accompanied by bifid
median cleft palate x-ray findings
unusually wide defect in anterior sphenoid region; mass at skull base air pocket between frontal horns
present defect in sphenoid & posterior ethmoid; mass at skull base agenesis of corpus callosum; dilatation of lateral ventricles not performed
complete defect in sphenoethmoidal region; mass at skull base not performed
pneumoencephalogram computerized tomography
not performed
operation
direct transpalatal correction
tions of these two cases indicate the presence of both median cleft lip and palate and agenesis of the corpus callosum. Extensive search through the literature indicates that the incidence of sphenoethmoidal meningoencephalocele, agenesis of the corpus callosum, 9,a4 and median cleft lip and palate) respectively, are very rare findings, but in the three cases cited, including our own, all three of these anomalies were present together. Gerlach 4 mentioned the association of congenital hydrocephalus and cleft lip and palate with sphenoethmoidal meningoencephalocele. As no explanation was provided as to the cause of hydrocephalus, we propose that agenesis of the corpus callosum may be the underlying cause for this finding. DeMyer 3 applied the general term "median cleft face syndrome" to patients with median cleft palate and lip and other anomalies, and suggested the possibility that agenesis of the corpus callosum and meningoencephalocele may occur in this syndrome. It is certainly possible that these malformations constitute a single unit of congenital anomalies. Several mechanisms have been proposed to account for the development of congenital basal meningoencephalocele. 11 In our case, it seems logical to assume that shift of the mesenchyme of the mesoderm was obstructed for some reason, resulting in anomalies in formation of the median aspect of the face? ,a As formation of the lips takes place earliest, during the sixth week of gestation, it is felt that for all three of these anomalies to coexist, the mechanism that triggers their development must already be present by then. When the mass of basal meningoencephalocele is large, the patients will develop respiratory disturbance or CSF rhinorrhea, and will be unable to survive beyond the early phase of life. However, in cases 400
Case 2 (Pollock, et al., 1968)
intracranial approach
nose
agenesis of corpus callosum; dilatation of lateral ventricles not performed
where the mass is not large, some patients have developed normally without being diagnosed, and have undergone surgery after attaining adulthood? ,1~ Therefore, so long as there is no remarkable respiratory disturbance or spontaneous CSF leakage, we believe that the recommended policy should be periodic follow-up observation? ,8 The surgical procedures generally used for basal meningoencephalocele are the intracranial or transpalatal approach, 8,8,1~ but whichever is used, it is necessary to fill in the bone defect and take measures to make the dura mater watertight. Acknowledgment We are greatly indebted to Professor Mineo Yasuda, Department of Anatomy, Hiroshima University School of Medicine, for providing his interpretation of the embryological basis for development of these anomalies.
References 1. Akashi K, Nagai M, Chigasaki H, et al: [Cranium bifidum and its special type (cephalocele nasopharyngealis).] Brain Nerve 20:813-823, 1968 (Jpn) 2. Bell WE, Van Allen MW" Agenesis of the corpus callosum with associated facial anomalies. Neurology 9:694-698, 1959 3. DeMyer W: Median facial malformations and their implications for brain malformations, in Bergsma D, Langman J, Paul NW: Morphogenesis and Malformation of Face and Brain. New York: Alan R Liss, 1975, pp 155-181 4. Gerlach J: Missbildungen des Sch/idels und des Gehirns. C. Missbildungen des Gehirns und der Hirnh/iute. I. Die Cephalocelen, in Olivecrona H, TSnnis W: Handbueh der Neurochirurgie, IV/I. Berlin/Heidelberg/New York: Springer-Verlag, 1960, pp 169-183
J. Neurosurg. / Volume51 / September, 1979
Sphenoethmoidal mening oencephalocele 5. Gisselsson L: Intranasal forms o1 encephalomeningocele. Acta Otolaryngol 35:519-53 I, 1947 6. Ingraham FD, Matson DD: Spina bifida and cranium bifidum. IV. An unusual nasopharyngeal encephalocele. N Engl J Med 228:815-820, 1943 7. Lau BP, Newton TH: Sphenopharyngeal encephalomeningocele. Radiol Clin 34:386-398, 1965 8. kewin ML, Shuster MM: Transpalatal correction of basilar meningocele with cleft palate. Arch Surg 90:687-693, 1965 9. Loeser JD, Alvord EC Jr: Clinicopathological correlations in agenesis of the corpus callosum. Neurology 18:745-756, 1968 10. New PJF, Scott WR: Computed Tomography of the Brain and Orbit (EMI Scanning). Baltimore: Williams and Wilkins, 1975 11. Pollock JA, Newton TH: Encephalocele and cranium bifidum, in Newton TH, Potts DG (eds): Radiology of the Skull and Brain, Vol 1, Book 2. St. Louis: CV Mosby, 1971, pp 634-647 12. Pollock JA, Newton TH, Hoyt WF: Transsphenoidal and transethmoidal encephaloceles: a review of clinical and roentgen features in 8 cases. Radiology 90:442-453, 1968
J. Neurosurg. / Volume51 / September, 1979
13. Suwanwela C, Suwanwela N: A morphological classification of sincipital encephalomeningoceles. J Neurosurg 36:201-211, 1972 14. Van Epps EF: Agenesis of the corpus callosum with concomitant malformations, including atresia of the foramen of Luschka and Magendie. Am J Roentgenol Radium Ther Nucl Med 70:47-60, 1953 15. Van Nouhuys JM, Bruyn GW: Nasopharyngeal transsphenoidal encephalocele, craterlike hole in the optic disc and agenesis of the corpus callosum: pneumoencephalographic visualisation in a case. J Psyehiatr Neurol Neurochir 67:243L258, 1964 16. Weise GM, Kempe LG, Hammon WM: Transsphenoida[ meningohydroencephalocele. Case report. J Neurosurg 37:475-478, 1972
Address reprint requests to." Katsuaki Sakoda, M.D., Department of Neurosurgery, School of Medicine, Hiroshima University, Kasumi 1-2-3, Hiroshima, Japan.
401
Sphenoethmoidal meningoencephalocele associated with agenesis of corpus callosum and median cleft lip and palate Case report
KATSUAKI SAKODA, M.D., SUSUMU ISHIKAWA, M.D., TOHRU UOZUMI, M.D., KATSUHIRO HIRAKAWA, M.D., HIDEO OKAZAKI, M.D., AND YASUO HARADA, M.D. Departments of Neurosurgery and Oto-Rhino-Laryngology, School of Medicine, Hiroshima University, Hiroshima, Japan A case of sphenoethmoidal meningoencephalocele associated with agenesis of the corpus callosum and median cleft lip and palate in a baby boy is reported. Two other cases have been reported previously presenting exactly the same findings. It is possible that these malformations constitute a distinct type of congenital anomaly. KEY WORDS sphenoethmoidal meningoencephalocele median cleft lip 9 median cleft palate 9
C
ASES with basal meningoencephalocele are rare and few cases have been reported. Recently, we encountered a case of sphenoethmoidal meningoencephalocele, one of the types of basal meningoencephalocele, associated with median cleft lip and palate and agenesis of corpus callosum. This case is presented together with a review of the literature. Case Report This baby boy was born on November 10, 1976. His mother's last menstrual cycle began on February 6, 1976. She received an injection of 17-hydroxyprogesterone caproate for vaginal bleeding that was noticed on March 31. At the same time, she took meclizine hydrochloride, 75 mg daily for 14 days, because of severe emesis. She caught cold on September 30, but otherwise her subsequent course was uneventful. No family history of congenital anomalies could be elicited. The patient was delivered normally at full term and birth weight was 2650 gm. Immediately after birth, median cleft lip and palate were noted. Plastic surgery of the median cleft lip was J. Neurosurg. / Volume51 / September, 1979
9 agenesis of corpus callosum
performed uneventfully at another hospital on April 22, 1977. On June 28, 1978, he underwent surgery for cleft palate at the Department of Oto-RhinoLaryngology, Hiroshima University School of Medicine. During the course of the operation, a soft mass was noticed for the first time to te proiect ing into the oral cavity at the site of the nasal septum. Needle aspiration of the mass revealed clear fluid, and he was referred to the Department of Neurosurgery with the suspicion of meningocele. The head circumference was 47 cm. The bregmatic fontanel was completely closed. No abnormalities of the skull and spine were noted on inspection and palpation. The interpupillary distance was 5.0 cm, but hypertelorism was not grossly apparent (Fig. 1). Surgical wounds were noted in the upper lip and median portion of the palate, but no bulging of the mass into the oral cavity was observed. As the right nasal cavity was almost completely occluded by the mass, the patient had to open his mouth slightly to breathe, but there was no respiratory distress. There were no findings indicative of retardation in mental and physical development. 397
K. Sakoda, et al.
Flc. 1. The interpupillary distance is 5.0 cm,
but
hypertelorism is not grossly apparent. Median cleft lip has been surgically repaired.
Tomography revealed a defect, 2.0 cm wide, anterior to the sella turcica, and a mass that filled the nasal cavity. The bone defect was narrow at the front, and the mass was localized at the nasal septum. Computerized tomography (CT) revealed a bone defect located anterior to the sella turcica in the middle of the anterior fossa, and a bone-like bridge which delineated the posterior margin of the defect (Fig. 3). The anterior horns were separated, the posterior horn of the lateral ventricles was dilated, and the third ventricle was deformed and dilated, probably due to agenesis of the corpus callosum. 1~ On the basis of these findings, the case was considered to be sphenoethmoidal meningoencephalocele associated with agenesis of the corpus callosum and median cleft palate and lip. As there was no leakage of cerebrospinal fluid (CSF) nor significant respiratory symptoms, it was decided not to perform radical surgery, but to conduct strict follow-up observation. Discussion
The anteroposterior projection of a plain skull film showed that the interorbital distance was 3.2 cm; an oval-shaped density, 3.0 • 1.4 cm in size, could be seen extending down into the nasal cavity. On the lateral view, the bone defect and the mass could not be clearly observed. The basal view of the skull showed a well circumscribed bone defect with pyramidal-shaped anterior and hemicircular-shaped posterior portions located anterior to the sella turcica (Fig. 2).
It has been said that the incidence of basal meningoencephalocele is one in 35,000 births, 15 but reported cases are very rare. According to Ingraham and Matson 6 among a total of 546 cases of meningocele in the central nervous system, there were 84 cases with meningoencephalocele, of which one was of the transethmoidal type. However, in Japan, only one case of transethmoidal type has been reported among a total of 33 cases of meningoencephalocele. 1
F~. 2. Radiograph, basal view, of the skull. A sharply circumscribed defect can be clearly observed through the anterior skull base.
meningoencephalocele at the sphenoethmoidal region. The bridge of bone is well shown at the site oflimbus sphenoidale (arrow).
398
FIG. 3. Computerized
tomography
scan
reveals
J. Neurosurg. / Volume 51 / September, 1979
Sphenoethmoidal
meningoencephalocele
When a location in the cranial vault is excluded, meningoencephalocele can be grouped into sincipital and basal types. The sincipital type is described in detail by Suwanwela and Suwanwela. 13The basal type may be further subgrouped into transethmoidal, sphenoethmoidal, transsphenoidal, spheno-orbital, and sphenomaxillary types, depending on the site of the bone defect and extension of the mass (Fig. 4)? .1113 The bone defect in the transsphenoidal type is found in the sphenoid bone, particularly at the base of the sella turcica. Eleven cases of this type have been reported in the literature. 7.8,1~,15.x~ In the sphenoethmoidal type, the mass extends into the nasal cavity through the bone defect between the ethmoid and sphenoid bones; our case falls into this category. Although the sphenoethmoidal type is classified as a type of basal meningoencephalocele, review of the literature failed to produce any cases designated as such. The reason is considered to be due to difficulty in differentiating between the sphenoethmoidal and transsphenoidal types on the basis of x-ray examination and surgery. In our case, it was possible to detect a bone bridge on the CT scan. An essential point in establishing the diagnosis of sphenoethmoidal meningoencephalocele is the location of this bridge of bone at the site of limbus sphenoidale (Fig. 5). Two additional cases which could also be considered sphenoethmoidal were found among cases classified as transsphenoidal: the single case reported by Lewin and Shuster? and Case III of Pollock, et al. ~2 (Table 1). In describing their case, Lewin and Shuster stated, "X-ray film of the skull showed a defect in the anterior sphenoid region and a defect posterior to the cribriform plate," which is considered to meet the definition established for sphenoethmoidal
FK~. 4. Sites of bone defect in the cases of sincipital (1) and basal (2-5) meningoencephalocele. 2 = transethmoidal type; 3 - sphenoethmoidal type; 4 - transsphenoidal type (sphenopharyngeal type); 5 = spheno-orbital type.
type. Pollock, et al., described their Case III as follows: "On roentgenologic examination, a large osseous defect was seen in the sphenoid and posterior ethmoid, and a 2 • 3.5 cm osseous defect in the midline extended from posterior clinoids to within 1 cm of the posterior margin of the cribriform plate." It is difficult from the description to establish that the latter case was sphenoethmoidal. However, large transsphenoidal defects are commonly accompanied by hypothalamic dysfunction, hypopJtuitarism, and visual loss, 1' and as their case app~orently failed to demonstrate such evidence, we believe that it could well be interpreted as sphenoethmoidal. The descrip-
FIG. 5. Diagrams comparing transsphenoidal type (right) with sphenoethmoidal type (left). J. Neurosurg. / Volume51 / September, 1979
399
K. Sakoda, et al. TABLE 1 Summary of reported cases of sphenoethmoidal meningoencephalocele Clinical Features
Case 1 (Lewin & Shuster, 1965)
Case 3 (present case)
age sex hypertelorism median cleft lip
15 mos male striking central triangular defect
16 mos male mild present
19 mos male unnoticed accompanied by bifid
median cleft palate x-ray findings
unusually wide defect in anterior sphenoid region; mass at skull base air pocket between frontal horns
present defect in sphenoid & posterior ethmoid; mass at skull base agenesis of corpus callosum; dilatation of lateral ventricles not performed
complete defect in sphenoethmoidal region; mass at skull base not performed
pneumoencephalogram computerized tomography
not performed
operation
direct transpalatal correction
tions of these two cases indicate the presence of both median cleft lip and palate and agenesis of the corpus callosum. Extensive search through the literature indicates that the incidence of sphenoethmoidal meningoencephalocele, agenesis of the corpus callosum, 9,a4 and median cleft lip and palate) respectively, are very rare findings, but in the three cases cited, including our own, all three of these anomalies were present together. Gerlach 4 mentioned the association of congenital hydrocephalus and cleft lip and palate with sphenoethmoidal meningoencephalocele. As no explanation was provided as to the cause of hydrocephalus, we propose that agenesis of the corpus callosum may be the underlying cause for this finding. DeMyer 3 applied the general term "median cleft face syndrome" to patients with median cleft palate and lip and other anomalies, and suggested the possibility that agenesis of the corpus callosum and meningoencephalocele may occur in this syndrome. It is certainly possible that these malformations constitute a single unit of congenital anomalies. Several mechanisms have been proposed to account for the development of congenital basal meningoencephalocele. 11 In our case, it seems logical to assume that shift of the mesenchyme of the mesoderm was obstructed for some reason, resulting in anomalies in formation of the median aspect of the face? ,a As formation of the lips takes place earliest, during the sixth week of gestation, it is felt that for all three of these anomalies to coexist, the mechanism that triggers their development must already be present by then. When the mass of basal meningoencephalocele is large, the patients will develop respiratory disturbance or CSF rhinorrhea, and will be unable to survive beyond the early phase of life. However, in cases 400
Case 2 (Pollock, et al., 1968)
intracranial approach
nose
agenesis of corpus callosum; dilatation of lateral ventricles not performed
where the mass is not large, some patients have developed normally without being diagnosed, and have undergone surgery after attaining adulthood? ,1~ Therefore, so long as there is no remarkable respiratory disturbance or spontaneous CSF leakage, we believe that the recommended policy should be periodic follow-up observation? ,8 The surgical procedures generally used for basal meningoencephalocele are the intracranial or transpalatal approach, 8,8,1~ but whichever is used, it is necessary to fill in the bone defect and take measures to make the dura mater watertight. Acknowledgment We are greatly indebted to Professor Mineo Yasuda, Department of Anatomy, Hiroshima University School of Medicine, for providing his interpretation of the embryological basis for development of these anomalies.
References 1. Akashi K, Nagai M, Chigasaki H, et al: [Cranium bifidum and its special type (cephalocele nasopharyngealis).] Brain Nerve 20:813-823, 1968 (Jpn) 2. Bell WE, Van Allen MW" Agenesis of the corpus callosum with associated facial anomalies. Neurology 9:694-698, 1959 3. DeMyer W: Median facial malformations and their implications for brain malformations, in Bergsma D, Langman J, Paul NW: Morphogenesis and Malformation of Face and Brain. New York: Alan R Liss, 1975, pp 155-181 4. Gerlach J: Missbildungen des Sch/idels und des Gehirns. C. Missbildungen des Gehirns und der Hirnh/iute. I. Die Cephalocelen, in Olivecrona H, TSnnis W: Handbueh der Neurochirurgie, IV/I. Berlin/Heidelberg/New York: Springer-Verlag, 1960, pp 169-183
J. Neurosurg. / Volume51 / September, 1979
Sphenoethmoidal mening oencephalocele 5. Gisselsson L: Intranasal forms o1 encephalomeningocele. Acta Otolaryngol 35:519-53 I, 1947 6. Ingraham FD, Matson DD: Spina bifida and cranium bifidum. IV. An unusual nasopharyngeal encephalocele. N Engl J Med 228:815-820, 1943 7. Lau BP, Newton TH: Sphenopharyngeal encephalomeningocele. Radiol Clin 34:386-398, 1965 8. kewin ML, Shuster MM: Transpalatal correction of basilar meningocele with cleft palate. Arch Surg 90:687-693, 1965 9. Loeser JD, Alvord EC Jr: Clinicopathological correlations in agenesis of the corpus callosum. Neurology 18:745-756, 1968 10. New PJF, Scott WR: Computed Tomography of the Brain and Orbit (EMI Scanning). Baltimore: Williams and Wilkins, 1975 11. Pollock JA, Newton TH: Encephalocele and cranium bifidum, in Newton TH, Potts DG (eds): Radiology of the Skull and Brain, Vol 1, Book 2. St. Louis: CV Mosby, 1971, pp 634-647 12. Pollock JA, Newton TH, Hoyt WF: Transsphenoidal and transethmoidal encephaloceles: a review of clinical and roentgen features in 8 cases. Radiology 90:442-453, 1968
J. Neurosurg. / Volume51 / September, 1979
13. Suwanwela C, Suwanwela N: A morphological classification of sincipital encephalomeningoceles. J Neurosurg 36:201-211, 1972 14. Van Epps EF: Agenesis of the corpus callosum with concomitant malformations, including atresia of the foramen of Luschka and Magendie. Am J Roentgenol Radium Ther Nucl Med 70:47-60, 1953 15. Van Nouhuys JM, Bruyn GW: Nasopharyngeal transsphenoidal encephalocele, craterlike hole in the optic disc and agenesis of the corpus callosum: pneumoencephalographic visualisation in a case. J Psyehiatr Neurol Neurochir 67:243L258, 1964 16. Weise GM, Kempe LG, Hammon WM: Transsphenoida[ meningohydroencephalocele. Case report. J Neurosurg 37:475-478, 1972
Address reprint requests to." Katsuaki Sakoda, M.D., Department of Neurosurgery, School of Medicine, Hiroshima University, Kasumi 1-2-3, Hiroshima, Japan.
401
