Transsphenoidal meningoencephalocele in adults

Developmental

Transsphenoidal Meningoencephalocele in Adults Anthony Jabre, M.D.,* Ronald Tabaddor, M.D.,* and Ranji Samaraweera, M.D.† Departments of *Neurosurgery and †Neuroradiology, Boston University and Boston Veterans Administration Medical Center, Boston, Massachusetts

Jabre A, Tabbador R, Samaraweera R. Transsphenoidal Meningoencephalocele in adults. Surg Neurol 2000;54:183– 8. BACKGROUND

Transsphenoidal meningoencephalocele is a rare congenital anomaly, reported only in 14 adult patients. It may be subdivided into intrasphenoidal, extending into the sphenoid sinus, and true transsphenoidal, traversing the floor of the sinus and protruding into the nasal cavity or nasopharynx. METHODS

We present the eighth case of true transsphenoidal meningoencephalocele reported in an adult. We review the literature and highlight the differences in clinical presentation and therapeutic management between patients with intrasphenoidal and true transsphenoidal meningoencephalocele. CONCLUSION

Adult patients with intrasphenoidal meningoencephalocele often present with rhinorrhea and should be considered for transsphenoidal repair, whereas patients with true transsphenoidal meningoencephalocele should not undergo surgery, in view of the complex anatomy and the slow progression of symptoms. © 2000 by Elsevier Science Inc. KEY WORDS

Hypertelorism, intrasphenoidal, meningoencephalocele, rhinorrhea, transsphenoidal.

ranssphenoidal meningoencephalocele is a congenital anomaly that consists of herniation through a sphenoidal bony defect of an ependymalined sac filled with cerebrospinal fluid (CSF) and containing neural vascular tissue. It may encompass the third ventricle, hypothalamic–pituitary elements, anterior cerebral arteries, and optic apparatus [21,27]. Different theories have been advanced to explain the pathogenesis of basal encephaloceles; among these are failure of ossification centers to fuse, leading to herniation of meninges and neural tissues [23], and persistence of the

T

Address reprint requests to: Dr. Anthony Jabre, Boston University Medical Center, 720 Harrison Avenue, Suite 710, Boston, Massachusetts 02118. Received February 24, 2000; accepted June 20, 2000. © 2000 by Elsevier Science Inc. 655 Avenue of the Americas, New York, NY 10010

craniopharyngeal canal, allowing downward displacement of intracranial contents [16]. The majority of transsphenoidal meningoencephaloceles are diagnosed during the first year of life due to manifestations such as respiratory distress caused by epipharyngeal obstruction, cranial midline defects with cleft lip or cleft palate, hypertelorism, optic malformations with anophthalmia, retinal abnormalities, optic nerve hypoplasia, or unexplained bouts of recurrent meningitis [7,8,10, 11,17,18,20,21,24,27]. Presentation in adults is rare, as congenital facial anomalies are subtle or absent and diagnosis is delayed until rhinorrhea occurs, a visual field defect becomes evident, hormonal deficiency is noted, or an epipharyngeal mass is discovered. Our review of the literature revealed 14 cases of transsphenoidal meningoencephalocele diagnosed in adults [1,2,4,6,12,13,15,18,19,21,22,25, 26]. Among those, seven were intrasphenoidal and confined by the floor of the sphenoid sinus [1,4,6, 13,15,21,25] and seven were true transsphenoidal, protruding through the floor of the sphenoid sinus into the nasal cavity or nasopharynx [2,12,18,19, 21,22,26]. We report the eighth case of a true transsphenoidal meningoencephalocele in an adult and discuss the previously reported cases. We emphasize the benefit of distinguishing between the intrasphenoidal type and the true transsphenoidal type, as there are differences in clinical presentation and surgical indication.

Case Report A 61-year-old man with a known history of alcohol abuse tripped over a folding chair at home and fell to the ground with transient loss of consciousness. He was seen in the emergency room and noted to be alert but disoriented. His pupils were equal, round, and reactive to light. His extraocular movements 0090-3019/00/$–see front matter PII S0090-3019(00)00270-6

184 Surg Neurol 2000;54:183–8

Jabre et al

Coronal CAT scan with bone window showing a large well corticated bone defect in the sella floor, traversed by an intracranial soft tissue mass extending between separated sphenoidal air cells into the nasopharynx through the floor of the sphenoid sinus.

1

were full. His fundi revealed disc pallor. His strength was normal and he had no sensory asymmetry. His deep tendon reflexes were trace and the plantar response was downgoing bilaterally. Computed axial tomography (CAT) scan of the brain revealed a cystic mass extending from the third ventricle into the nasopharynx, through the sphenoid sinus. The diagnosis of true transsphenoidal meningoencephalocele was further confirmed by CAT scan with coronal sections and bone window (Figure 1) and by magnetic resonance imaging (MRI) (Figures 2A, B). Otolaryngology assessment revealed a 4 cm pulsating mucosal mass in the nasopharynx and a small unilateral alveolar premaxillary defect. There was no past history of cerebrospinal fluid leak and none was noted upon examination. In retrospect the patient acknowledged a right cleft lip that was repaired during childhood. The maxillary hard palate, the soft palate, and the uvula were normal. Ophthalmology evaluation revealed mild hypertelorism, normal pupils, and no afferent pupillary defect. The visual acuity was 20/25 in both eyes. The funduscopic examination showed disc pallor consistent with bilateral optic neuropathy, and the visual field perimetry revealed bitemporal field deficit with central vision preservation. Full endocrine evaluation was unremarkable. At the conclusion of the work-up, observation was advised. Clinical, laboratory and MRI evaluations a year later have remained unchanged.

Discussion Cephaloceles occur in approximately one of every 3000 to 5000 live births [5,14]. Equally divided between males and females, they have a 30% incidence of associated anomalies [3]. Suwanwela proposed a classification into frontal, occipital, parietal, and basal [23]. Basal meningoencephaloceles, which occur with an estimated incidence of one in every 35,000 live births [14] have been further subdivided, depending on the location of the bone defect, into transethmoidal, sphenoethmoidal, sphenoorbital and transsphenoidal [23]. The transsphenoidal type represents less than 5% of all basal meningoencephaloceles and has an estimated incidence of one in 700,000 live births [9]. Finally, based on the integrity of the sphenoid sinus floor, Abiko et al noted 2 types of transsphenoidal meningoencephaloceles: the intrasphenoidal and the true transsphenoidal. The former describes those extending into the sphenoid sinus but confined by its floor. The latter describes those traversing the floor of the sphenoid sinus and protruding into the nasal cavity or nasopharynx [1]. Fourteen adult patients with transsphenoidal meningoencephalocele have been reported in the literature; seven with intrasphenoidal meningoencephaloceles and seven with true transsphenoidal meningoencephaloceles. We add an eighth case to the latter group. Clinical presentation may include CSF rhinorrhea

Transsphenoidal meningoencephalocele

Surg Neurol 185 2000;54:183–8

T1- (A) and T2-weighted (B) sagittal MRI, showing the prolapsed meningoencephalocele containing the inferiorly displaced recesses of the third ventricle along with the hypothalamus. The pituitary gland and infundibulum seem to be displaced further caudally, within the nasopharyngeal component of the meningocele. The optic chiasm lies in the region of the pituitary fossa.

2

[4,6,15,25,3]; visual impairment, most notably visual field defect, decreased visual acuity, amaurosis, or amblyopia [1,2,12,13,18,19,21,22,26]; endocrine dysfunction, especially hypogonadism, hypothyroidism, hyperprolactenemia or diabetes insipidus [1,12,13,18,19,21,22,26]; and cranial facial defects, mostly hypertelorism [2,12,13,18,19,22,26]. In the intrasphenoidal group (Table 1), four patients presented with CSF rhinorrhea and three patients with visual impairment. Three patients had endocrine dysfunction and four had none or none

reported. Significantly, all patients except one underwent surgery, most often through a transsphenoidal approach, and all had good postoperative results with control of rhinorrhea or improvement in vision. In the true transsphenoidal group (Table 2), none of the patients presented with CSF rhinorrhea, possibly because of the thickened mucosal lining surrounding the meningoencephalocele sac in the nasopharynx, as observed in our case. All had visual impairment and the majority had endocrine dysfunction.

186 Surg Neurol 2000;54:183–8

1

Jabre et al

Intrasphenoidal Meningoencephalocele in Adults

PRESENTING SYMPTOM

ENDOCRINE DYSFUNCTION

CASE

AUTHOR, YEAR

AGE/SEX

1

McCoy [15] 1963 Danoff [4] 1966 Debartolo [6] 1977 Manelfe [13] 1978 Vaquero [25] 1981 Smith [21] Case #2 1983 Abiko [1] 1988

40/F

CSF rhinorrhea

Not known

Intranasal (good)

41/F 41/F

CSF rhinorrhea CSF rhinorrhea

Not known No

Transcranial (good) Transethmoid (good)

57/M

Visual impairment

Yes

Transsphenoidal (good)

56/F

CSF rhinorrhea

Not known

Transsphenoidal (good)

52/M

Visual impairment

Yes

No

46/F

Visual impairment

Yes

Transsphenoidal (good)

2 3 4 5 6 7

cephalocele, association with significant facial, optic or brain malformations is common. Surgical morbidity, mainly through transcranial repair, has reached 70% and mortality 50% [5,27]. However, a recent article by Kennedy et al reports minimal morbidity with the transpalatal approach [8].

Significantly, none had a direct surgical repair of the meningoencephalocele, although one patient [2] had undergone an attempted transcranial subfrontal repair which was abandoned due to the complex and distorted anatomy encountered intraoperatively, including anomalous and tortuous arterial vessels. Another patient [19] had a concomitant suprasellar epidermoid cyst that was surgically resected through a transfrontal craniotomy, but no attempt was made to repair the meningoencephalocele. Finally, a third patient [21] underwent an exploratory subfrontal craniotomy for a presumptive pituitary tumor; the intraoperative findings revealed thickened arachnoid over the optic nerves and an empty pituitary fossa. Surgical repair of the meningoencephalocele was not pursued. The five remaining patients did not undergo surgery, and although long-term follow-up is lacking, none seems to have suffered rapid deterioration or untoward effect with conservative management. In children with transsphenoidal meningoen-

2

SURGERY (OUTCOME)

Conclusion It would seem from this review that adult patients with intrasphenoidal meningoencephalocele often present with rhinorrhea and should be considered for transsphenoidal repair, with the expectation of a good outcome. However, patients with true transsphenoidal meningoencephalocele should not undergo surgery, because of the complexity of the distorted anatomy and the generally slow progression of symptoms. Long-term follow-up is essential to determine the natural history.

True Transsphenoidal Meningoencephalocele in Adults

CASE

AUTHOR, YEAR

AGE/SEX

CSF RHINORRHEA

VISUAL IMPAIRMENT

ENDOCRINE DYSFUNCTION

1

Lau [12] Case 2 1965 Pollack [18] Case 5 1968 Avanzini [2] 1970 Weise [26] 1972 Streletz [22] 1973 Sadeh [19] 1982 Smith [21] Case 1 1983 Jabre & Tabaddor 2000

33/M

No

Yes

Yes

No

48/M

No

Yes

Yes

No

34/M 20/M 35/M 27/F 67/M

No No No No No

Yes Yes Yes Yes Yes

No Yes Yes Yes Yes

Attempted transcranial No No Excision of epidermoid Exploratory craniotomy

61/M

No

Yes

No

No

2 3 4 5 6 7 8

SURGERY

Transsphenoidal meningoencephalocele

REFERENCES 1. Abiko S, Aoki H, Fudaba H. Intrasphenoidal encephalocele: report of a case. Neurosurgery 1988;22: 933– 6. 2. Avanzini G, Crivelli G. A case of sphenopharyngeal encephalocele. Acta Neurochir 1970;22:205–12. 3. Batsakis JG. Tumors of the head and neck: clinical and pathological considerations, ed 2. Baltimore: Williams and Wilkins, 1979, 514 –30. 4. Danoff D, Serbu J, French LA. Encephalocele extending into the sphenoid sinus: Report of a case. J Neurosurg 1966;24:684 – 6. 5. David DJ, Proudman TW. Cephaloceles: classification, pathology, and management. World J Surg 1989;13: 349 –57. 6. DeBartolo HM, Vrabec D. Sphenoid encephalocele. Arch Otolaryngol 1977;103:172– 4. 7. DeMyer W. The median cleft face syndrome. Differential diagnosis of cranium bifidum occultum, hypertelorism and median cleft nose, lip and palate. Neurology 1967;17:961–71. 8. Diebler C, Dulac O. Cephaloceles: clinical and neuroradiological appearance associated cerebral malformation. Neuroradiology 1983;25:199 –216. 9. French BN. Midline fusion defects and defects of formation. In: Youmans JR, ed. Neurological surgery. Vol 3. Philadelphia: Saunders, 1982, 1236 –1380. 10. Kenna MA. Transsphenoidal encephalocele. Ann Otorhinolaryngol 1985;94:520 –2. 11. Kennedy EM, Gruber DP, Billmire DA, Crone KR. Transpalatal approach for the extra cranial surgical repair of transsphenoidal encephalocele in children. J Neurosurg 1997;87:677– 81. 12. Lau BP, Newton TH. Sphenopharyngeal encephalomeningocele. Radiol Clin 1965;34:386 –98. 13. Manelfe C, Starling-Jardim D, Touibi S, Bonafe A, David J. Transsphenoidal encephalocele associated with agenesis of corpus callosum: Value of metrizamide computed cisternography. J Comput Assist Tomogr 1978;2:356 – 61. 14. Matson DD. Neurosurgery of infancy and childhood, ed 2. Springfield, IL: Charles C Thomas, 1969, p. 68. 15. McCoy G. Cerebrospinal rhinorrhea: a comprehensive review and a definition of the responsibility of the rhinologist in diagnosis and treatment. Laryngoscope 1963;73:1125–57. 16. Mood GF. Congenital anterior herniations of brain. Ann Otorhinolaryngol 1938;47:391– 401. 17. Mylanus EAM, Marres HAM, Vlietman J, Freihofer HPM, Thijssen HOM, Devries J, Wessling P. Transalar sphenoidal encephalocele and respiratory distress in a neonate: A case report. Pediatrics 1999; 103:E121–E124. 18. Pollack JA, Newton TH, Hoyt WF. Transsphenoidal and transethmoidal encephaloceles. Radiology 1968; 90:442–53. 19. Sadeh M, Goldhammer Y, Shacked I, Tadmor R, Godel V. Basal encephalocele associated with suprasellar epidermoid cyst. Arch Neurol 1982;39:250 –2. 20. Shimizu T, Kitamura S, Kinouchi K, Fukumitsu K. A rare case of upper airway obstruction in an infant caused by basal encephalocele complicating midline deformity. Paediatric Anaest 1999;9:73– 6.

Surg Neurol 187 2000;54:183–8

21. Smith DE, Murphy MJ, Hitchon PW, Babin RW, Abu Yousef MM. Transsphenoidal encephaloceles. Surg Neurol 1983;20:471– 80. 22. Streletz LJ, Schatz NJ. Transsphenoidal encephalocele associated with colobomas of the optic discs and hypopituitary dwarfism. In: Smith JL, Glasser JS, eds. Symposium of the University of Miami and the Bascom Palmer Eye Institute. St Louis: CV Mosby, 1973:78 – 86. 23. Suwanwela C, Suwanwela N. A morphologic classification of sincipital encephalomeningoceles. J Neurosurg 1972;30:201–11. 24. Tsutsumi K, Asano T, Matsui T, Shigeno T, Ito S, Kaizu H. Transcranial approach for transsphenoidal encephalocele: Report of two cases. Surg Neurol 1999; 51:252–7. 25. Vaquero J, Cabezudo JM, Salazar AR, Brasa J. Symptomatic intrasphenoidal meningoencephalocele after removal of a parasagittal meningioma. Acta Neurochir (Wien) 1981;57:61–5. 26. Weise GM, Kempe LG, Hammon WM. Transsphenoidal meningoencephalocele: Case report. J Neurosurg 1972;37:475– 8. 27. Yokota A, Matsukado Y, Fuwa I, Moroki K, Nagahiro S. Anterior basal encephalocele of the neonatal and infantile period. Neurosurgery 1986;19:468 –78.

COMMENTARY

Currently, the accepted classification of cranial encephalocele is based on the anatomical location of the skull defect, as suggested by Suwanwela in 1972. Basal encephalocele refers to those lesions that protrude through the floor of the anterior cranial fossa: transsphenoidal (intrasphenoidal and true transsphenoidal), spheno-orbital, sphenomaxillary, and spheno-ethmoidal. The clinical manifestations in children are usually related to breathing difficulties—noisy breathing or recurrent upper respiratory infections—recurrent meningitis, or cerebrospinal fluid leakage after a “biopsy of a nasal polyp.” Other associated anomalies can include hypertelorism, anophthalmia, optic nerve abnormalities such as midline cleft syndrome, hypothalamic pituitary dysfunction, craniosynostosis, Chiari malformation, Dandy-Walker cyst, and corpus callosum dysgenesis. The authors present an adult case of true transsphenoidal encephalocele. This patient presented with mild external features of hypertelorism and a past history of cleft lip repair and visual symptoms, but no CSF leakage. The literature review reports 14 adults with encephalocele (7 intersphenoid, 7 true transsphenoidal). It is noted that in the adult form of intersphenoidal encephalocele, CSF rhinorrhea was observed in four (57%) and visual symptoms in three (43%); in true transsphenoidal encephalocele, none had

188 Surg Neurol 2000;54:183–8

Jabre et al

CSF rhinorrhea, but all had visual impairment, which was conservatively managed without surgical repair. Because the important structures of the brain are involved and distorted by the encephalocele, the transcranial, transpalatal, or even a combined approach is not without significant morbidity and mortality. In adult patients who are in no immediate

danger of meningitis or worsening of neurological status, conservative management is prudent and acceptable. Yoon S. Hahn, M.D. Pediatric Neurosurgery Hope Children’s Hospital Chicago, Illinois

eavy thoughts bring on physical maladies; when the soul is oppressed, so is the body.

H

—Martin Luther