Ann Otol 88 :1979
ANEURYSMAL BONE CYST OF MAXILLA KEVIN
J.
KANE, FRACS
MELBOURNE, AUSTRALIA
A case of aneurysmal bone cyst of the maxilla is reported. The clinical and radiological features, histopathology and treatment, are described in detail. Although the pathogenesis is still obscure, surgical excision is considered to be the treatment of choice.
Aneurysmal bone cyst was first described as a distinct entity by Jaffe and Lichtenstein.' A number of confusing and diverse synonyms had previously been used, such as ossifying hematoma, expansile hemangioma and aneurysmal giant cell tumors." Aneurysmal bone cyst is a benign lesion characterized by bulging or ballooning of cortical bone due to the associated underlying expanding fibrovascular mass. This expansion causes endosteal resorption and periosteal deposition of cortical bone. The condition is uncommon and found predominantly in the vertebral column and long bones." For a cyst to arise in the facial bones is rare. The present case describes the lesion arising in the maxilla of a 14-yearold boy. CASE HISTORY
W. c., a 14-year-old boy, in October 1973, developed recurrent bleeding from the left nostril associated with a swelling of the left eye. Later there was mild pain over the left cheek with accompanying toothache and nasal obstruction. There was no previous history of trauma to the face or jaw. On clinical examination there was a left proptosis with marked swelling of the left cheek and broadening of the left side of the nose (Fig. lA). A pink, fleshy swelling was seen filling the left nostril and this had displaced the septum to the right side, with resulting obstruction of the nostril. The swelling had extended into the postnasal space and was seen to be smooth and pale yellow in color, obscuring the posterior nares. A biopsy of the nasal swelling had
been performed at another hospital and had been histologically reported as an aneurysmal bone cyst. Radiological examination of the sinuses demonstrated opacification of the left maxillary, frontal and ethmoidal sinuses. Anteroposterior and basal skull tomography revealed the presence of extensive bone destruction affecting the posteromedial aspects of the left antrum extending to the pterygoid plates. Left carotid angiography demonstrated the orbital branches of maxillary artery to be displaced posteriorly and the ophthalmic artery to be elevated by an almost avascular mass on the medial aspect of the left antrum and orbit. There was no evidence of any large feeding vessel to the mass, though a faint capillary blush was observed in the late stages of the angiogram. Computer tomography (EMI scan) demonstrated a high density abnormality on the medial aspect of the left orbit, displacing the left eye forward. There was no evidence of any intracranial extension and the intracranial contents appeared normal. Further investigations including a chest x-ray, full blood count examination and estimation of the serum calcium, phosphorus, alkaline phosphatase and five nucleotidase were performed and found to be normal. In order to accurately assess the limits of the lesion, the left maxillary sinus was explored by a gingivobuccal approach and the postnasal space examined. The swelling could be seen completely occluding the posterior nares and as far as could be determined, the tumor had
From the Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia.
217 Downloaded from aor.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 8, 2015
218
KEVIN ]. KANE
Fig. 1. A) Preoperative photograph. There is a left proptosis with fullness of the check and broadening of the left nostril. B) Two months postoperatively.
no obvious attachments. The full extent of the tumor however, could not be defined with this limited operation and it was decided that a more adequate exploration was required. The maxilla was exposed via a Weber-Ferguson incision with a frontoethmoidal extension as used for excision of a maxilla.
A bismuth-iodoform-paraffin paste pack was placed into the antral and nasal cavities and the wound closed; this was removed six days later. Three weeks after operation the proptosis and swelling of the left cheek had disappeared and the patient is tumor free five years postoperatively (Fig. IB).
The skin flaps were elevated from the anterior surface of the maxilla and lateral surface of the nose and immediately the tumor was seen to have destroyed the anterior wall of the maxillary sinus in its outer half. The bone in the infraorbital and ethmoidal region was very thin as a result of pressure and the tumor could be seen through it. The tumor occupied the whole of the maxillary antrum, the nasal cavity, ethmoid sinus and postnasal space. Further bone was then removed from the anterior wall of the maxilla, the orbital and frontal processes of the maxilla and the nasal bones, giving an excellent exposure of the tumor mass. It was then possible with blunt dissection, to mobilize the tumor fully within the antrum, the only attachment being to the mucosa covering the posterior wall. The tumor was seen to have a dumbbell appearance with a constriction at the nasoantral wall, where it had passed into the nasal cavity through the middle meatus. After this mobilization, it was removed in toto. This left a huge continuous cavity of the antrum and left nostril. The mucosa of the nasal wall was kept intact and placed over the floor of the antrum to facilitate healing.
Fig. 2. Low power view of aneurysmal bone cyst. The section shows large vascular spaces. Near these spaces large darkly staining giant cells can be seen. (H & E, X 38)
Downloaded from aor.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 8, 2015
ANEURYSMAL BONE CYST OF MAXILLA
Fig. 3. High power view of aneurysmal bone cyst. Numerous red cells are present throughout the tissue along with several histiocytes. In the top right hand corner a giant cell is present and the large vascular space appears to have no true endothelium. (H & E, X 96)
Histology. The macroscopic appearance was that of a brown, honeycombed cystic tumor expanding and partially destroying bone. The capsule was new subperiosteal bone. The microscopic appearance revealed large blood-containing spaces lined by granulation tissue with numerous giant cells and extensive interstitial hemorrhage (Figs. 2-4). The giant cells were not evenly distributed throughout the tissues, but in many cases were confined to the edge of the spaces. Collagen was present, but no smooth muscle nor elastin. Heavy deposits of iron were found. Histiocytes were found among the fibrocytes. The vascular spaces were not lined by endothelium. In effect, the "tumor" was a vascular granuloma. DISCUSSION
Aneurysmal bone cysts are benign, localized and expanding fibrous lesions
219
Fig. 4. High power view of one of the multinucleate giant cells present in the section. (X 384).
which contain an enormously dilated, plexiform vascular bed. As they expand, cortical bone is thinned, but usually a shell covering is preserved. Most authorities consider that the cyst is not a neoplasm, but an aberration of a reparative process in bone. Geschickter and Copeland" suggested that an aneurysmal bone cyst develops as a result of a subperiosteal hemorrhage due to an injury or local malformation and a subsequent aberration in tissue organization occurs. Bernier and Bhaskar" take this one step further and suggest that the injured blood vessel forms a type of arteriovenous communication with the hematoma and that the cavernous plexus within the lesion is, in fact, part of the recanalization of the hematoma. In the present case, the blood channels were not dilated vessels, since tissue stains failed to show elastic or muscular tissue in the walls. There was no evidence that the lesion represented a "false aneurysm" of a blood vessel in which the attached hematoma had been re-
Downloaded from aor.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 8, 2015
220
KEVIN
canalized. Carotid angiography demonstrated a relatively avascular structure and during the operation no major feeding vessels were encountered. Lichtenstein" suggested also that the aneurysmal bone cyst arises as a result of a circulatory disturbance, such as thrombosis of a large vein or anomalous arteriovenous communication with resultant dilatation and increased pressure within the vascular bed. This transference of arterial pressure to the venous side is thought to cause the pressure resorption effect of bone.
Clinical Features. The majority of cases occur in the 10 to 20 year age group, with a slight female preponderance. The most common presentation of the maxillary lesions is that of a slow, progressive expansion of the maxilla, giving rise to either a swelling in the cheek or of the palate. Nasal obstruction is a less common feature and in all cases, pain has been absent. A history of trauma has been found in about 70% of cases. It is not clear, however, whether the trauma is the initiating factor or the method by which attention is drawn to the lesion. Radiological features are characteristic in the long bones, where the lesion is usually eccentric and has a honeycomb or soap bubble appearance. The cortex is often destroyed and new periosteal bone formation is apparent. These features are less apparent in the maxilla, but expansion of the maxillary antrum may be demonstrated by tomography. Angiography is essential to exclude a nasopharyngeal angiofibroma.
Differential Diagnosis. Aneurysmal bone cysts had been confused with giant cell tumors of bone (osteoclastoma). Indeed, limb amputation has been carried out on such histological criteria. Giant cell tumors are, however, rare below 20 years of age and histologically, multinucleated giant cells are far more in evidence occupying most of the microscopical field. Aneurysmal bone cysts have much in common with giant cell reparative granulomas of jaw bones. These lesions occur only in the mandible and maxilla. Like aneurysmal bone
J.
KANE
cysts, giant cell reparative granulomas are more common in the female, occur in the same age group and have the same clinical features. Histologically, the supporting connective tissues in the two lesions are identical except for the absence of blood spaces in the granulomas. Bernier and Bhaskar,' extending their theory of pathogenesis of aneurysmal bone cysts, suggest that the giant cell reparative granuloma represents an organized hematoma in which the damaged blood vessels fail to retain a circulatory connection with the lesion.
It is interesting to note that in the case of aneurysmal bone cyst of the maxilla reported by Yarington, 7 both histological types were present and he assumed that, in fact, two separate tumors were present. It seems more probable, however, that the appearances were due to the same lesion in different stages of development. Finally, it is important to exclude the "brown tumor" of hyperparathyroidism. The histological picture of both these lesions often resembles the "brown tumor" closely and thus the chemical determination of serum calcium, phosphorus and alkaline phosphatase is mandatory. Treatment. Since the lesion is benign, extensive or radical surgery is in general contraindicated. Most cases of aneurysmal bone cyst of the mandible appear to respond to simple curettage. Nine previous cases involving the maxilla have been reported in the world literature and all were treated surgically.7,9-I4 Most only required a gingivobuccal approach for their removal, but two required a partial maxillectomy. There is no mention of any recurrence in these cases, in contrast to the recurrence rate observed in other areas of the body. When the location of the lesion makes it inaccessible to surgery, radiotherapy may be undertaken. The usual recommended dose is 1,400 to 2,000 rads." Irradiation should, however, be resorted to with caution, since most of these lesions occur in children. There is no report of malignant transformation of the tumor itself following
Downloaded from aor.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 8, 2015
ANEURYSMAL BONE CYST OF MAXILLA
radiotherapy, but Tillman" stated three cases of the 95 treated at the Mayo
221
Clinic developed fibrosarcoma and osteogenic sarcoma at the tumor site.
REFERENCES 1. Jaffee HL, Lichtenstein L: Solitary unicameral bone cyst, with emphasis on roentgen picture, pathologic appearance and pathogenesis. Arch Surg 44: 1004-1025, 1942 2. Ewing J: Neoplastic Diseases, ed 4. Philadelphia, WB Saunders Co, 1940, p 323 3. Jaffe HL: Ansurysmal bone cyst. Bull Hosp Joint Dis 11 :3-13, 1950 4. Geschickter CF, Copeland MM: Tumours of Bone, ed 3. Philadelphia, JB Lippincott Co, 1949, p 316 5. Bernier JL, Bhaskar SN: Aneurysmal bone cysts of the mandible. Oral Surg 11: 10181028, 1958 6. Lichtenstein L: Aneurysmal bone cyst; pathological entity commonly mistaken for giant cell tumor and occasionally for hemangioma and osteogenic sarcoma. Cancer 3:279289, 1950 7. Yarington CT Jr, Abbott J, Raines D: Aneurysmal bone cyst of the maxilla; association with giant cell reparative granuloma. Arch Otolaryngol 80:313-317, 1964
8. Byrd DL, Allen JW, Kindrick RD, et al: Aneurysmal bone cyst of the maxilla. J Oral Surg 27 :296-300, 1969 9. Ellis DJ, Walters PJ: Aneurysmal bone cyst of the maxilla. Oral Surg 34:26-32, 1972 10. Gruskin SE, Dahlin DC: Aneurysmal bone cysts of the jaws. J Oral Surg 26:523528, 1968 11. Le jeune FE [r, Bordelon JP: Aneurysmal bone cyst of the maxillary antrum. Eye Ear Nose Throat Monthly 49:216-217, 1970 12. Romaniuk K, Becker R: Two cases of aneurysmal bone cysts of the jaws. Int J Oral Surg 1: 48-52, 1972 13. Vianna MR, Horizonte B: Aneurysmal bone cyst in the maxilla: Report of case. J Oral Surg 20:432-434, 1962 14. Wang SY: An aneurysmal bone cyst in the maxilla. Plast Reconstr Surg 25:62-72, 1960 15. Tillman BP, Dahlin DC, Lipscomb PR, et al: Aneurysmal bone cyst: An analysis of 95 cases. Mayo Clin Proc 43:478-495, 1968
REPRINTS - Kevin J. Kane, FRACS, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia.
XII WORLD CONGRESS OF OTORHINOLARYNGOLOGY The XII World Congress of Otorhinolaryngology will be held June 21-26, 1981 in Budapest, Hungary. Preliminaiy communications, recommendations and suggestions, should be directed to Prof. Dr. L. Surjan, President, XII World Congress of ORL, H-1389 Budapest, Pf: 112 Hungary.
Downloaded from aor.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 8, 2015
ANEURYSMAL BONE CYST OF MAXILLA KEVIN
J.
KANE, FRACS
MELBOURNE, AUSTRALIA
A case of aneurysmal bone cyst of the maxilla is reported. The clinical and radiological features, histopathology and treatment, are described in detail. Although the pathogenesis is still obscure, surgical excision is considered to be the treatment of choice.
Aneurysmal bone cyst was first described as a distinct entity by Jaffe and Lichtenstein.' A number of confusing and diverse synonyms had previously been used, such as ossifying hematoma, expansile hemangioma and aneurysmal giant cell tumors." Aneurysmal bone cyst is a benign lesion characterized by bulging or ballooning of cortical bone due to the associated underlying expanding fibrovascular mass. This expansion causes endosteal resorption and periosteal deposition of cortical bone. The condition is uncommon and found predominantly in the vertebral column and long bones." For a cyst to arise in the facial bones is rare. The present case describes the lesion arising in the maxilla of a 14-yearold boy. CASE HISTORY
W. c., a 14-year-old boy, in October 1973, developed recurrent bleeding from the left nostril associated with a swelling of the left eye. Later there was mild pain over the left cheek with accompanying toothache and nasal obstruction. There was no previous history of trauma to the face or jaw. On clinical examination there was a left proptosis with marked swelling of the left cheek and broadening of the left side of the nose (Fig. lA). A pink, fleshy swelling was seen filling the left nostril and this had displaced the septum to the right side, with resulting obstruction of the nostril. The swelling had extended into the postnasal space and was seen to be smooth and pale yellow in color, obscuring the posterior nares. A biopsy of the nasal swelling had
been performed at another hospital and had been histologically reported as an aneurysmal bone cyst. Radiological examination of the sinuses demonstrated opacification of the left maxillary, frontal and ethmoidal sinuses. Anteroposterior and basal skull tomography revealed the presence of extensive bone destruction affecting the posteromedial aspects of the left antrum extending to the pterygoid plates. Left carotid angiography demonstrated the orbital branches of maxillary artery to be displaced posteriorly and the ophthalmic artery to be elevated by an almost avascular mass on the medial aspect of the left antrum and orbit. There was no evidence of any large feeding vessel to the mass, though a faint capillary blush was observed in the late stages of the angiogram. Computer tomography (EMI scan) demonstrated a high density abnormality on the medial aspect of the left orbit, displacing the left eye forward. There was no evidence of any intracranial extension and the intracranial contents appeared normal. Further investigations including a chest x-ray, full blood count examination and estimation of the serum calcium, phosphorus, alkaline phosphatase and five nucleotidase were performed and found to be normal. In order to accurately assess the limits of the lesion, the left maxillary sinus was explored by a gingivobuccal approach and the postnasal space examined. The swelling could be seen completely occluding the posterior nares and as far as could be determined, the tumor had
From the Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia.
217 Downloaded from aor.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 8, 2015
218
KEVIN ]. KANE
Fig. 1. A) Preoperative photograph. There is a left proptosis with fullness of the check and broadening of the left nostril. B) Two months postoperatively.
no obvious attachments. The full extent of the tumor however, could not be defined with this limited operation and it was decided that a more adequate exploration was required. The maxilla was exposed via a Weber-Ferguson incision with a frontoethmoidal extension as used for excision of a maxilla.
A bismuth-iodoform-paraffin paste pack was placed into the antral and nasal cavities and the wound closed; this was removed six days later. Three weeks after operation the proptosis and swelling of the left cheek had disappeared and the patient is tumor free five years postoperatively (Fig. IB).
The skin flaps were elevated from the anterior surface of the maxilla and lateral surface of the nose and immediately the tumor was seen to have destroyed the anterior wall of the maxillary sinus in its outer half. The bone in the infraorbital and ethmoidal region was very thin as a result of pressure and the tumor could be seen through it. The tumor occupied the whole of the maxillary antrum, the nasal cavity, ethmoid sinus and postnasal space. Further bone was then removed from the anterior wall of the maxilla, the orbital and frontal processes of the maxilla and the nasal bones, giving an excellent exposure of the tumor mass. It was then possible with blunt dissection, to mobilize the tumor fully within the antrum, the only attachment being to the mucosa covering the posterior wall. The tumor was seen to have a dumbbell appearance with a constriction at the nasoantral wall, where it had passed into the nasal cavity through the middle meatus. After this mobilization, it was removed in toto. This left a huge continuous cavity of the antrum and left nostril. The mucosa of the nasal wall was kept intact and placed over the floor of the antrum to facilitate healing.
Fig. 2. Low power view of aneurysmal bone cyst. The section shows large vascular spaces. Near these spaces large darkly staining giant cells can be seen. (H & E, X 38)
Downloaded from aor.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 8, 2015
ANEURYSMAL BONE CYST OF MAXILLA
Fig. 3. High power view of aneurysmal bone cyst. Numerous red cells are present throughout the tissue along with several histiocytes. In the top right hand corner a giant cell is present and the large vascular space appears to have no true endothelium. (H & E, X 96)
Histology. The macroscopic appearance was that of a brown, honeycombed cystic tumor expanding and partially destroying bone. The capsule was new subperiosteal bone. The microscopic appearance revealed large blood-containing spaces lined by granulation tissue with numerous giant cells and extensive interstitial hemorrhage (Figs. 2-4). The giant cells were not evenly distributed throughout the tissues, but in many cases were confined to the edge of the spaces. Collagen was present, but no smooth muscle nor elastin. Heavy deposits of iron were found. Histiocytes were found among the fibrocytes. The vascular spaces were not lined by endothelium. In effect, the "tumor" was a vascular granuloma. DISCUSSION
Aneurysmal bone cysts are benign, localized and expanding fibrous lesions
219
Fig. 4. High power view of one of the multinucleate giant cells present in the section. (X 384).
which contain an enormously dilated, plexiform vascular bed. As they expand, cortical bone is thinned, but usually a shell covering is preserved. Most authorities consider that the cyst is not a neoplasm, but an aberration of a reparative process in bone. Geschickter and Copeland" suggested that an aneurysmal bone cyst develops as a result of a subperiosteal hemorrhage due to an injury or local malformation and a subsequent aberration in tissue organization occurs. Bernier and Bhaskar" take this one step further and suggest that the injured blood vessel forms a type of arteriovenous communication with the hematoma and that the cavernous plexus within the lesion is, in fact, part of the recanalization of the hematoma. In the present case, the blood channels were not dilated vessels, since tissue stains failed to show elastic or muscular tissue in the walls. There was no evidence that the lesion represented a "false aneurysm" of a blood vessel in which the attached hematoma had been re-
Downloaded from aor.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 8, 2015
220
KEVIN
canalized. Carotid angiography demonstrated a relatively avascular structure and during the operation no major feeding vessels were encountered. Lichtenstein" suggested also that the aneurysmal bone cyst arises as a result of a circulatory disturbance, such as thrombosis of a large vein or anomalous arteriovenous communication with resultant dilatation and increased pressure within the vascular bed. This transference of arterial pressure to the venous side is thought to cause the pressure resorption effect of bone.
Clinical Features. The majority of cases occur in the 10 to 20 year age group, with a slight female preponderance. The most common presentation of the maxillary lesions is that of a slow, progressive expansion of the maxilla, giving rise to either a swelling in the cheek or of the palate. Nasal obstruction is a less common feature and in all cases, pain has been absent. A history of trauma has been found in about 70% of cases. It is not clear, however, whether the trauma is the initiating factor or the method by which attention is drawn to the lesion. Radiological features are characteristic in the long bones, where the lesion is usually eccentric and has a honeycomb or soap bubble appearance. The cortex is often destroyed and new periosteal bone formation is apparent. These features are less apparent in the maxilla, but expansion of the maxillary antrum may be demonstrated by tomography. Angiography is essential to exclude a nasopharyngeal angiofibroma.
Differential Diagnosis. Aneurysmal bone cysts had been confused with giant cell tumors of bone (osteoclastoma). Indeed, limb amputation has been carried out on such histological criteria. Giant cell tumors are, however, rare below 20 years of age and histologically, multinucleated giant cells are far more in evidence occupying most of the microscopical field. Aneurysmal bone cysts have much in common with giant cell reparative granulomas of jaw bones. These lesions occur only in the mandible and maxilla. Like aneurysmal bone
J.
KANE
cysts, giant cell reparative granulomas are more common in the female, occur in the same age group and have the same clinical features. Histologically, the supporting connective tissues in the two lesions are identical except for the absence of blood spaces in the granulomas. Bernier and Bhaskar,' extending their theory of pathogenesis of aneurysmal bone cysts, suggest that the giant cell reparative granuloma represents an organized hematoma in which the damaged blood vessels fail to retain a circulatory connection with the lesion.
It is interesting to note that in the case of aneurysmal bone cyst of the maxilla reported by Yarington, 7 both histological types were present and he assumed that, in fact, two separate tumors were present. It seems more probable, however, that the appearances were due to the same lesion in different stages of development. Finally, it is important to exclude the "brown tumor" of hyperparathyroidism. The histological picture of both these lesions often resembles the "brown tumor" closely and thus the chemical determination of serum calcium, phosphorus and alkaline phosphatase is mandatory. Treatment. Since the lesion is benign, extensive or radical surgery is in general contraindicated. Most cases of aneurysmal bone cyst of the mandible appear to respond to simple curettage. Nine previous cases involving the maxilla have been reported in the world literature and all were treated surgically.7,9-I4 Most only required a gingivobuccal approach for their removal, but two required a partial maxillectomy. There is no mention of any recurrence in these cases, in contrast to the recurrence rate observed in other areas of the body. When the location of the lesion makes it inaccessible to surgery, radiotherapy may be undertaken. The usual recommended dose is 1,400 to 2,000 rads." Irradiation should, however, be resorted to with caution, since most of these lesions occur in children. There is no report of malignant transformation of the tumor itself following
Downloaded from aor.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 8, 2015
ANEURYSMAL BONE CYST OF MAXILLA
radiotherapy, but Tillman" stated three cases of the 95 treated at the Mayo
221
Clinic developed fibrosarcoma and osteogenic sarcoma at the tumor site.
REFERENCES 1. Jaffee HL, Lichtenstein L: Solitary unicameral bone cyst, with emphasis on roentgen picture, pathologic appearance and pathogenesis. Arch Surg 44: 1004-1025, 1942 2. Ewing J: Neoplastic Diseases, ed 4. Philadelphia, WB Saunders Co, 1940, p 323 3. Jaffe HL: Ansurysmal bone cyst. Bull Hosp Joint Dis 11 :3-13, 1950 4. Geschickter CF, Copeland MM: Tumours of Bone, ed 3. Philadelphia, JB Lippincott Co, 1949, p 316 5. Bernier JL, Bhaskar SN: Aneurysmal bone cysts of the mandible. Oral Surg 11: 10181028, 1958 6. Lichtenstein L: Aneurysmal bone cyst; pathological entity commonly mistaken for giant cell tumor and occasionally for hemangioma and osteogenic sarcoma. Cancer 3:279289, 1950 7. Yarington CT Jr, Abbott J, Raines D: Aneurysmal bone cyst of the maxilla; association with giant cell reparative granuloma. Arch Otolaryngol 80:313-317, 1964
8. Byrd DL, Allen JW, Kindrick RD, et al: Aneurysmal bone cyst of the maxilla. J Oral Surg 27 :296-300, 1969 9. Ellis DJ, Walters PJ: Aneurysmal bone cyst of the maxilla. Oral Surg 34:26-32, 1972 10. Gruskin SE, Dahlin DC: Aneurysmal bone cysts of the jaws. J Oral Surg 26:523528, 1968 11. Le jeune FE [r, Bordelon JP: Aneurysmal bone cyst of the maxillary antrum. Eye Ear Nose Throat Monthly 49:216-217, 1970 12. Romaniuk K, Becker R: Two cases of aneurysmal bone cysts of the jaws. Int J Oral Surg 1: 48-52, 1972 13. Vianna MR, Horizonte B: Aneurysmal bone cyst in the maxilla: Report of case. J Oral Surg 20:432-434, 1962 14. Wang SY: An aneurysmal bone cyst in the maxilla. Plast Reconstr Surg 25:62-72, 1960 15. Tillman BP, Dahlin DC, Lipscomb PR, et al: Aneurysmal bone cyst: An analysis of 95 cases. Mayo Clin Proc 43:478-495, 1968
REPRINTS - Kevin J. Kane, FRACS, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia.
XII WORLD CONGRESS OF OTORHINOLARYNGOLOGY The XII World Congress of Otorhinolaryngology will be held June 21-26, 1981 in Budapest, Hungary. Preliminaiy communications, recommendations and suggestions, should be directed to Prof. Dr. L. Surjan, President, XII World Congress of ORL, H-1389 Budapest, Pf: 112 Hungary.
Downloaded from aor.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 8, 2015
