Ann Otol Rhinal Laryngol99: 1990

NASOPHARYNGEAL CRANIOPHARYNGIOMA CASE REPORT AND LITERATURE REVIEW MARIA

N.

DONALD

BYRNE, MD

G.

SESSIONS, MD

ST LOUIS, MISSOURI

NEW HAVEN, CONNECTICUT

Craniopharyngioma is an intracranial tumor that occurs rarely in the infrasellar region. Eight patients with craniopharyngioma located within the nasopharynx have been reported previously. These cases originated in the nasopharynx and involved the sella turcica (6), the sphenoid sinus (1), and the vomer (1). Craniopharyngioma usually originates intracranially. When there is no evidence of sellar involvement, the tumor most likely arises along the path of the craniopharyngeal duct. According to the neurosurgical literature, the optimal treatment consists of total surgical excision. Incomplete tumor removal is supplemented by adjunctive radiotherapy, which has been shown to significantly increase the survival rate. A patient with craniopharyngioma of the nasopharynx and paranasal sinuses who presented with nasal obstruction is reported. Radiographic studies were employed for tumor evaluation, and biopsy was done to establish the histopathologic diagnosis. Treatment included a combination of surgical excision and irradiation. KEY WORDS -

craniopharyngioma, nasopharynx.

Theory of Origin. The theory of the origin of craniopharyngioma along the tract of the obliterated craniopharyngeal duct was first proposed in 1904 by Erdheirn," who observed the pharyngeal hypophysis to be located on the posterior edge of the vomerine bone. In 1931 Carmichael" found remnants of the obliterated craniopharyngeal duct in the immediate region of the pituitary gland in 32.7% of the autopsy cases he studied. McGrath 7 . 8 later demonstrated the presence of functioning pharyngeal hypophysis in the adult, with a vascular communication from the hypothalamic-hypophyseal portal system through the sphenoid bone to the vascular bed of the pharyngeal hypophysis. Craniopharyngioma may originate anywhere along the tract of the obliterated craniopharyngeal duct, and further, within the functioning pharyngeal hypophysis itself. This could account for an infrasellar location of the tumor along the posterior aspect of the vomer above the junction of the soft palate and nasal septum, the sphenoid bone, and the undersurface of the floor of the sella.

INTRODUCTION Craniopharyngioma is a benign epithelial neoplasm primarily confined within the boundaries of the skull. It comprises approximately 3 % of all intracranial tumors. The tumor arises in the area of the sella turcica, with a suprasellar location being the most common. Rare lesions have been described within the sella, the third ventricle, and the infrasellar region. The infrasellar tumors can be located within the sphenoid bone and nasopharynx, and thus extend beyond the boundaries of the skull."?

Embryology. There are several theories regarding the origin of craniopharyngioma. Most of them are based on the embryologic development of the adenohypophysis. The tumor is postulated to arise from the remnants of the pharyngeal hypophysis. In the fourth week of gestation, an ectodermally lined diverticulum develops in the roof of the stomodeum just anterior to the oropharyngeal membrane. This is the pouch of Rathke, and it ascends cranially to meet the neuroectoderm of the infundibulum (neurohypophysis), which descends as a neural outgrowth from the floor of the third ventricle (diencephalon) of the embryonic brain. Rathke's pouch eventually differentiates into the anterior lobe of the pituitary, the adenohypophysis. The path traversed by Rathke's pouch remains as a solid cord of cells connecting the rudimentary adenohypophysis to the ectoderm of the stomodeum. Later in the embryonic life this cord disintegrates, leaving an obliterated craniopharyngeal canal. It is a tract that runs from the anterior part of the hypophyseal fossa of the sphenoid bone to the exterior of the skull, to the junction of the posterior septum of the nose with the palate, which is the stomodeal end of the recess."

Clinical Presentation. Craniopharyngiomas can arise at any age, although most occur in the first two decades of life. 1 Symptoms and clinical findings are related to the tumor's mass effect and compression of the surrounding structures. The optic chiasm is commonly affected, often with visual changes such as blurred vision, diplopia, visual field defects (mostly bitemporal hemianopsia), bizarre scotomata patterns, and blindness. Headache is a frequent symptom, and may be accompanied by vomiting. Other findings include hydrocephalus and papilledema, as well as hypopituitarism secondary to anterior pituitary dysfunction. Mental changes and occasional cranial nerve involvement are also observed.v"

From the Department of Otolaryngology-Head and NeckSurgery, Washington University, St Louis. Missouri. Dr Byrne is currently with the Southern New England Ear Nose and Throat Group and the Hospital of Saint Raphael, New Haven. Connecticut. REPRINTS - Donald G. Sessions, MD, Dept of Otolaryngology, Washington University School of Medicine, 517 S Euclid, Room 806, St Louis, MO 63110.

633

Downloaded from aor.sagepub.com at The University of Iowa Libraries on June 21, 2015

634

Byrne & Sessions, Nasopharyngeal Craniopharyngioma

\rt''l~M,:'h. '"l! "~~I' ~.' -1

, -.. .'~ftJ'ltff!:·.·".· .~"l .,(~ ...., .

41"t~

],'.

I oJ,r if'

•

Fig 1. Adamantinomatous craniopharyngioma demonstrating A) palisading rims of cuboidal or columnar epithelial cells arranged in characteristic pattern of cords, nests, and trabeculae (arrows) and B) degenerative changes with cholesterol clefts.

Diagnostic Evaluation. In evaluation of these tumors, radiographic studies are most helpful. Plain skull x-rays commonly show a suprasellar lesion with shortening and flattening of the dorsum sellae. Expansion and erosion of the sella turcica can be found with an intrasellar tumor. Multiple calcifications within the tumor are observed, especially in younger patients. In adults, craniopharyngiomas are often not calcified. Computed tomography usually reveals the heterogeneous nature of the tumor with its solid and cystic components. The extent of the soft tissue mass is well defined. Contrast studies or pneumoencephalography can be used to evaluate the hydrocephalus. Angiography is nonspecific for craniopharyngioma, reflecting only the presence of a mass. 10 - 12 Other diagnostic studies include cerebrospinal fluid analysis for protein content. In tumors confined to the sella turcica, the protein content is nor-

mal. When extrasellar extension is present, there is usually an increase in protein. 13 Finally, the function of the anterior pituitary is evaluated to assess the extent of the gland involvement.

Pathology. On a gross pathologic evaluation, craniopharyngioma is found to be of variable size, and cystic more often than solid. The cysts contain a yellow to dark fluid, laden with glistening cholesterol crystals, resembling "motor oil." The tumor is usually adherent, with invasion into the surrounding structures that prevents a complete removal. Microscopically, the tumor is subclassified into two types: adamantinomatous craniopharyngioma and papillary craniopharyngioma (suprasellar papillary squamous epithelioma). The adamantinomatous craniopharyngioma is usually nodular and multicystic. It consists of solid areas in which epithelial cells assume the adamantinomatous pattern with variable architecture of anastomosing trabeculae, nests,

Downloaded from aor.sagepub.com at The University of Iowa Libraries on June 21, 2015

Byrne & Sessions, Nasopharyngeal Craniopharyngioma

635

Fig 2. Papillary squam0';ls crani.opharyngioma consisting of well-differentiated squamous epithelial cells arranged as papillae lined with loose connective tissue. Note presence of keratin pearl (arrow).

cords, and cysts (Fig lA). These are surrounded by a characteristic pattern of a palisading rim of cuboidal or columnar epithelial cells resting on a basement membrane. Interspersed among them are areas of compact epithelial whorls and nodular foci of keratinization. Cyst formations are characterized by degenerative changes with cellular necrosis, calcifications, and cholesterol clefts (Fig IB). The second type, squamous papillary craniopharyng~om~, consists of cords and papillae of squamous epithelium separated by loose connective tissue stroma (F~g 2). Calcifications, palisaded cells, and. kerato~d nodules are rare. This type occurs predommantly in adults. Craniopharyngioma is a benign tumor, and to date no histologic malignancies have been re-

ported. 1.2 Treatment. Treatment of these tumors is mostly excisional, through a craniotomy or transsphenoid approach. 14 Earlier methods involved aspiration of a single cyst, evacuation of a multicystic mass, or tumor marsupialization. This relieved the pressure of the growing cyst, and thus led to a symptomatic improvement. Frequently, the cyst would recur, with return of symptoms. Complete removal of the tumor is the preferred procedure. This is often technically difficult because of adherence to surrounding structures. Residual epithelium that is left behind can be the source of recurrence.

Various adjunctive treatments have been tried to

Fig 3. Nuclear magnetic resonance scans. A) Coronal view demonstrating soft tissue m ass filling left nasal fossa, left maxillary sinus, and bilateral ethmoid air cells. Mass has nonhomogeneous density, with areas of very low signal intensity consistent with calcifications. High signal intensity in right maxillary sinus indicates mucous retention cyst. B) Axial view showing tumor mass present within nasal fossa, right maxillary sinus, and nasopharynx. Lesion extends into bony clivus (arrow).

Downloaded from aor.sagepub.com at The University of Iowa Libraries on June 21, 2015

636

Byrne & Sessions, Nasopharyngeal Craniopharyngioma NASOPHARYNGEAL CRANIOPHARYNGIOMA CASE REPORTS Patient Age Sex

Author

Year

Drummond"

1938

14

F

Podoshin et al"

1970

15

Prasad and Kwi'·

1975

Symptoms

Physical Findings

F

Nasal obstruction, headache, loss of vision (L), decreased vision (R) Nasal obstruction, chronic sinusitis

NPX and bilateral NF mass, hard and soft falate flattening, blindness (L), decreased vision (R NPX and bilateral NF mass

55

F

Nasal obstruction

NPX and bilateral NF mass

48

M Nasal obstruction, headache, diplopia, face hypoesthesia (L) F Headache, decreased vision (L), diplopia

NPX and (L) NF mass, lateral rectus weakness (L), infraorbital nerve hypoesthesia (L) Abducens nerve palsy (L), temporal hemianopsia (L) NPX mass, hard palate erosion, bitemporal hemianopsia, exophthalmos, hypertelorism, hypopituitarism NPX pedunculated mass

IlIum et al"

1977

14

Majlessi et al'8

1978

17

M Headache, blurred vision, mental status changes

Lewin et al"

1984

27

F

Maier"

1985

77

M Headache, fluid drainage from NPX

NPX drainage of fluid, CSF rhinorrhea

This report

1990

29

M Nasal obstruction

NPX and bilateral NF mass

Epistaxis

NPX - nasopharynx, NF - nasal fossa, CSF - cerebrospinal fluid.

prevent recurrence. They include instillation of radioactive agents such as gold, phosphorus, or yttrium into the tumor bed, intracystic chemotherapy, and systemic c'hemotherapy.lu6 Radiotherapy, once considered ineffective, is currently the adjunctive treatment most often used. Craniopharyngioma has been found to be radiosensitive, and radiotherapy plays a major role in preventing recurrence and improving survival. 17 Study of autopsy cases by Kramer" showed total destruction of residual tumor cells by radiotherapy. Amacher " reported that in a patient who had a subtotal tumor removal followed by radiotherapy, the remaining craniopharyngioma was completely necrosed. In the neurosurgical literature, the advocated treatment of intracranial craniopharyngioma is total removal of the tumor, which is possible in selected cases. Amacher!" stated that total excision of a tumor offers the best chance of long-term survival. When vital structures are involved and excision is compromised by significant risks of morbidity and mortality, subtotal removal of the tumor followed by supplemental radiotherapy is the preferred treatment. Postoperative radiotherapy has been reported by many authors to increase the recurrence-free survival rates.:"" In a recent study by Manaka et aP7 the 5- and lO-year survival rates were 88.9% and 76.0% for the irradiated group, and 34.9% and 27.1 % for the control group (nonirradiated), respectively. The study revealed a high statistical significance in the difference between the survival times of the irradiated and control groups (p < .0001). Cavazzuti et aP2 and Danoff et aP3 investigated radiotherapy's effects on the brain, and

they concluded that the effects of irradiation are comparable to those of surgical excision alone. Thus, the recommended treatment for craniopharyngioma is surgical excision, followed by radiotherapy in patients in whom total excision is not successful. 17-20 Since the long-term effects of irradiation on the brain tissue are not well known, longterm follow-up of the patients is necessary. 21 CASE REPORT

A 29-year-old man presented with a complete left nasal airway obstruction that had developed over a period of 3 years. One month prior to admission, a partial right nasal obstruction was noted. Examination revealed a mass in the left nasal fossa 1 cm from the vestibule, completely obstructing the airway. The right nasal fossa had a deviated septum with a mass present at the choana. The nasopharynx was totally occupied by a tumor. The remainder of the examination findings were normal. Results of routine laboratory tests were unremarkable. Sinus x-ray films revealed opacification of the left maxillary, posterior ethmoid, and sphenoid sinuses. There was destruction of the bony septa of the posterior ethmoid air cells and thinning of the medial wall of the left maxillary sinus. A mucous retention cyst was present in the right maxillary sinus. Computed tomography showed a large soft tissue mass occupying the left nasal fossa, the nasopharynx, and the left sphenoid sinus. Magnetic resonance imaging showed a large expansile mass within the left nasal fossa, the left maxillary sinus, the nasopharynx, and the left sphenoid sinus (Fig 3A). The mass extended posteriorly into the bony clivus (Fig 3B). It was nonhomoge-

Downloaded from aor.sagepub.com at The University of Iowa Libraries on June 21, 2015

637

Byrne & Sessions, Nasopharyngeal Craniopharyngioma NASOPHARYNGEAL CRANIOPHARYNGIOMA CASE REPORTS (Continued) Treatment

Radiographic Findings

Follow-up

Tumor Location

Transnasal tumor debulking

ST, SS, NPX

Not reported

Transpalatal tumor debulking

ST, SS, NPX

Not reported

Transpalatal tumor debulking

SS, NPX

Not reported

NPX biopsy with tumor drainage (surgical excision refused) Craniotomy, biopsy, irradiation (54 Gy), transpalatal tumor debulking

ST, SS, NPX

Not reported

ST, SS, NPX

Not reported

SXR: ST expansion and erosion, tumor calcifications

Craniotomy, biopsy

ST, SS, NPX

Not reported

SXR, TG: no lesion; CT: NPX mass; AG: normal SXR, TG: ST destruction, SS and NPX mass, petrous bone erosion (L), tumor calcifications SXR, CT: SS, NPX, ES, and MS mass; MRI: multicystic mass

Transpalatal en bloc tumor removal Radiotherapy (24 Gy, 41 Gy)

NPX

Not reported

SXR: ST floor flattening, SS expansion and erosion SXR: ST enlargement, SS erosion, hard palate erosion, tumor calcifications SXR, TG: ST floor erosion, SS erosion, NPX mass; AG: avascular mass SXR, TG: ST expansion and erosion TG: ST and SS erosion, NPX mass; AG: avascular mass

Lateral rhinotomy approach for tumor, radiotherapy (54 Gy)

ST, SS, NPX SS, ES, MS, NPX

Alive 8 yr after second course of radiotherapy No recurrence after 36 mo

5XR - skull x-ray, 5T - sella turcica, 55 - sphenoid sinus, TG - tomogram, AG - angiogram, NPX tomography, E5 - ethmoid sinuses, M5 - maxillary sinus, MRI - magnetic resonance imaging.

nasopharynx, CT -

computed

neous in consistency, with a suggestion of multiple tiny cysts and calcifications. The right maxillary sinus had a signal intensity consistent with a mucous retention cyst. The sella turcica, suprasellar region, brain parenchyma, and cerebrospinal fluid spaces were entirely normal. Carotid and vertebral angiography revealed that the tumor was avascular and that there was no evidence of intracranial invasion. Results of a biopsy of the left nasal mass were consistent with craniopharyngioma.

found to infiltrate the posterior wall of the sinus, as well as the clivus. With use of the operating microscope the outer cortex of these bones was drilled to expose the bone marrow. It was elected to leave the posterior cortex with gross tumor within the crevices of the marrow of the clivus and the posterior wall of the sphenoid sinus. The left nasolacrimal duct was cannulated. Posterior and anterior nasal packs were inserted for hemostasis, and the wound was closed meticulously.

The decision was made to treat the tumor with surgical excision followed by postoperative radiotherapy. A lateral rhinotomy approach was selected to obtain the best exposure of the left nasal fossa, the nasopharynx, and the left paranasal sinuses. A Weber-Fergusson lip-splitting incision was used and carried down through the periosteum laterally. Lateral and medial osteotomies were performed, and the nasal bones were reflected to the right. The left nasal fossa was visualized, and the tumor was exposed. An intraoperative frozen section confirmed the diagnosis of craniopharyngioma. The maxillary sinus was entered, and the anterior antral wall was removed with a drill. The tumor had destroyed much of the medial wall of the maxillary sinus and the lateral wall of the nasal fossa. The anterior ethmoid air cells were exposed next. The tumor involved the left nasal fossa, the left maxillary sinus, the left anterior and posterior ethmoid sinuses, and the entire nasopharynx. The tumor was intimately attached to the anterior wall of the sphenoid sinus and the clivus, but not to the nasal fossa, maxillary sinus, or ethmoid sinuses. The tumor was removed in several large pieces with minimal bleeding. The ethmoid sinuses were curetted. The anterior wall of the sphenoid sinus was removed, and tumor was

On gross inspection, the tumor consisted of solid areas, as well as cystic spaces filled with dark brown, oily fluid. Histopathologic evaluation of the tumor revealed multiple cysts and an adamantinomatous pattern, consistent with craniopharyngioma, of anastomosing cords lined by stellate epithelial cells with a single layer of peripheral palisading cells. There was squamous metaplasia with keratin production and focal calcifications. The patient underwent an uneventful recovery. On the fourth postoperative day, the posterior nasal pack was removed. This was done in the operating room with general anesthesia. The patient was discharged from the hospital on the eighth postoperative day. Radiotherapy consisting of a total of 54 Gy (30 fractions) was administered 1 month later. The nasolacrimal duct cannula was removed after completion of radiotherapy. The lacrimal system remained patent, without evidence of epiphora. The patient is free of disease 3 years later. LITERATURE REVIEW

In the literature, eight cases of extracranial craniopharyngioma have been described, all occupying the nasopharynx (see Table 24 - 3 0 ) . In six patients,

Downloaded from aor.sagepub.com at The University of Iowa Libraries on June 21, 2015

638

Byrne & Sessions, Nasopharyngeal Craniopharyngioma

this tumor involved the nasopharynx, as well as the sella turcica and the sphenoid sinus. One patient had the tumor within the nasopharynx and the sphenoid sinus only. Another patient had craniopharyngioma solely confined to the nasopharynx. In our patient, the tumor occupied the nasopharynx and the left sphenoid sinus, as well as the left ethmoid and maxillary sinuses. Nasal obstruction was observed in five patients, and epistaxis occurred in one. Physical examination revealed nasopharyngeal and/or nasal fossa masses in eight patients. In six cases with sella turcica involvement, headache, visual changes, and other central nervous system findings were noted. Skull x-ray study, tomograms, and computed tomography were the most common radiographic techniques employed in evaluation. They showed tumor expansion, bony erosion, and calcifications in a majority of the patients. In addition, our patient had magnetic resonance imaging, which detected a multicystic nature of the tumor, a presence of calcifications, and no evidence of sella turcica involvement. Angiography was done in four cases, confirming tumor avascularity. The Table further displays that surgical excision and radiotherapy were the main modes of treatment. A transnasal approach was used in the earliest reported case (1938).24 In four patients, a transpalatal removal was performed. Biopsy only was done in two patients, one via craniotomy, and the other of the nasopharynx. Our patient underwent tumor removal through a lateral rhinotomy approach. Radiotherapy was the only mode of treatment in one patient, and in another it was performed prior to operation. Our patient had postoperative radiotherapy. Information on long-term patient follow-up is unavailable. Six patients who underwent tumor excision had initial resolution of symptoms. In two patients, one with biopsy only and another who was treated with radiotherapy, a progression of the disease was observed. Our patient remains free of disease 3 years after treatment.

DISCUSSION Craniopharyngioma is a rare tumor. It arises

within the sella turcica and expands mainly into the suprasellar region. Occasionally, the tumor can occur without sellar involvement. This infrasellar craniopharyngioma may then originate anywhere along the tract of the obliterated craniopharyngeal duct, which would include the sphenoid bone, vomer, and nasopharynx; thus, Erdheim's theory" is supported. Surgical excision is the treatment of choice. The transpalatal approach for the infrasellar and intrasellar tumors has been the advocated technique. This surgical procedure was first recommended in 1927 by Loeb.:" It was later popularized by Owens" and Wilson.:" Johnson" described a case of craniopharyngioma of the intrasellar region with involvement of the sphenoid sinus, and was the first to apply the transpalatal approach for the tumor's removal. Subsequently, other surgeons (Podoshin et al,25 Prasad et al,26 Illum et al;" and Lewin et aP9) adopted Johnson's approach in cases of craniopharyngioma within the nasopharynx. The transpalatal approach, although it gives a good exposure of the nasopharynx and the posterior nasal cavity, can be too restrictive in extensive tumors. In addition, a significant velopalatine insufficiency can result. The lateral rhinotomy approach, first described in 1845 by Fergusson;" provides adequate exposure of tumors occupying the nasopharynx, nose, and paranasal sinuses. By using this approach we had a complete visualization of the tumor, and we were able to remove it all except the part infiltrating the clinoid bone marrow. The ability to have direct vision while working near the vital structures reduced the risks of potential intraoperative complications. We recommend this approach for the best visualization of infrasellar craniopharyngioma. When complete removal of the tumor is not possible, postoperative radiotherapy is the advocated treatment in patients with intracranial craniopharyngioma. We propose a similar approach to nasopharyngeal craniopharyngioma. Combined surgical excision and postoperative radiotherapy has been shown to increase the survival rates. Longterm follow-up of patients is required.

REFERENCES 1. Rubinstein LJ. Tumors of the central nervous system. Fascicle 6. 2nd series. Atlas of tumor pathology. Washington, DC: Armed Forces Institute of Pathology, 1972. 2. Burger PC, Vogel FS. Surgical pathology of the nervous system and its coverings. 2nd ed. New York, NY: John Wiley & Sons, 1982. 3. Petito CK, DeGirolami U, Earle KM. Craniopharyngiomas. A clinical and pathological review. Cancer 1976;37: 1944-52. 4. Warwick R, Williams PL. Gray's Anatomy. 35th British ed. Philadelphia, Pa: WB Saunders, 1973.

5. Erdheim J. Ueber Hypophysengangsgeschwulste und Himcholesteatome. Akad Wiss Wien 1904;113:537-726. 6. Carmichael HT. Squamous epithelial rests in the hypophysis cerebri. Arch Neurol Psychiatry 1931;26:966-75. 7. McGrath P. Aspects of the human pharyngeal hypophysis in normal and encephalic fetuses and neonates and their possible significance in the mechanism of its control. J Anat 1974;127: 65-81. 8. McGrath P. Vascularity of the environs of the human pharyngeal hypophysis as a possible indication of the mechanism of its control. J Anat 1972;112:185-93.

Downloaded from aor.sagepub.com at The University of Iowa Libraries on June 21, 2015

Byrne & Sessions, Nasopharyngeal Craniopharyngioma 9. Johnson NE. Craniopharyngioma - review with a discussion of transpalatal approach. Laryngoscope 1962;72:1731-49. 10. Davis DO. Neuroradiological diagnosis of sellar and parasellar lesions. Clin Neurosurg 1970;17:160-88. 11. Cabezudo JM, Vaquero J, Garcia-de Sola R, Leunda G, Nombela L, Bravo G. Computed tomography with craniopharyngiomas: a review. Surg NeuroI1981;15:422-7. 12. Ahn HS, Sexton CS, Zinreich J, Rosenbaum AE. Neuroradiologic techniques in the evaluation of lesionsof the skull base. Ear Nose Throat J 1986;65:53-68. 13. Bakay L. Spinal fluid proteins in tumors of the sellar region. Neurology 1958;8:455-60. 14. Baskin DS, Wilson CB. Surgical management of craniopharyngiomas. A review of 74 cases. J Neurosurg 1986;65:22-7. 15. Julow J, Lanyi F, Hayda M, Simkovics H, et al. The radiotherapy of cystic craniopharyngioma with intracystic instillation of goy silicate colloid. Acta Neurochir (Wien) 1985;74:94-9. 16. Trippi AC, Garner JT, Kassabian JT, Shelden CH. A new approach to inoperable craniopharyngiomas. Am J Surg 1969; 118:307-10. 17. Manaka S, Teramoto A, Takakura K. The efficacy of radiotherapy for craniopharyngioma. J Neurosurg 1985;62:648-56. 18. Kramer S. Craniopharyngioma: the best treatment is conservative surgery and postoperative radiation therapy. In: Morley TP, ed. Current controversies in neurosurgery. Philadelphia, Pa: WB Saunders, 1976:336-43. 19. Amacher AL. Craniopharyngioma: the controversy regarding radiotherapy. Childs Brain 1980;6:57-64. 20. Fischer EG. Treatment of craniopharyngiomas in children 1972-1981.J Neurosurg 1985;62:496-501. 21. Martins AN, Johnston JS, Henry JM, et al. Delayed radiation necrosis of the brain. J Neurosurg 1977;47:336-45.

639

22. Cavazzuti V, Fischer EG, Welch K, et al. Neurological and psychophysiological sequelae following different treatments of craniopharyngioma in children. J Neurosurg 1983;59:409-17. 23. Danoff BF, Cowchock FS, Kramer S. Childhood craniopharyngioma: survival, local control, endocrine and neurologic function following radiotherapy. Int J Radiat Oncol Bioi Phys 1983;9: 171-5. 24. Drummond WAD. Infrasellar adamantinoma. Proc R Soc Med 1938;32:200-7. 25. Podoshin L, Rolan L, Altman MM, Peyser E. "Pharyngeal" craniopharyngioma. J Laryngol Otol 1970;84:93-9. 26. Prasad U, Kwi NK. Clinical records. Nasopharyngeal craniopharyngioma. J Laryngol Otol 1975;89:445-52. 27. IlIum P, Elbrond 0, Nehen AM. Surgical treatment of nasopharyngeal craniopharyngioma. Radical removal by the transpalatal approach. J Laryngol Otol 1977;91:227-33. 28. Majlessi H, Shariat AS, Katirai A. Nasopharyngeal craniopharyngioma. Case report. J Neurosurg 1978;49:119-20. 29. Lewin R, Ruffolo E, Saraceno C. Craniopharyngioma arising in the pharyngeal hypophysis. South Med J 1984;77: 1519-23. 30. Maier HC. Craniopharyngioma with erosion and drainage into the nasopharynx. An autobiographical case report. J Neurosurg 1985;62:132-4. 31. Loeb HW. Operative surgery of the nose, throat and ear. St Louis, Mo: CV Mosby, 1927:155-6. 32. Owens H. Observations in treating seven cases of choanal atresia by transpalatine approach. Laryngoscope 1951;61:304-19. 33. Wilson CPo Approach to nasopharynx. Proc R Soc Med 1951;4:353-8. 34. Fergusson W. A system of practical surgery. In operations of the upper jaw. 2nd ed. Philadelphia, Pa: Lee & Blanchard, 1945.

XX INTERNATIONAL CONGRESS OF AUDIOLOGY The XX International Congress of Audiology will be held October 14-18, 1990, in Tenerife, Canary Islands, Spain. For further information, contact Dr Jose Barajas, Presidente, C/Perez de Rozas, 8, 38004 Santa Cruz de Tenerife, Canary Islands, Spain; telephone 22 27 54 88; telex 91106.

Downloaded from aor.sagepub.com at The University of Iowa Libraries on June 21, 2015