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Cranial osteomas: Their classification and management report on a giant osteoma and review of the literature
ELSEVIER
CRANIAL OSTEOMAS: THEIR CLASSIFICATION AND MANAGEMENT REPORT ON A GIANT THE LITERATURE
OSTEOMA
AND
REVIEW
OF
Fuad S. Haddad, M.D., F.R.C.S.(C.), F.A.C.S.,* Georges F. Haddad, M.D., F.R.C.S.(C.),* and Ghazi Zaatari, M.D.t
*Division of Neurosurgery, TDepartment of Pathology, American University of Beirut, Beirut, Lebanon
Haddad FS, Haddad GF, Zaatari C. Cranial osteomas: their classification and management. Report on a giant osteoma and review of the literature. Surg Neural 1997;48:143-7. BACKGROUND
Cranial osteomas are regarded by some as very common; yet their classification, symptomatology, and management have been neglected. METHODS
We report on a giant enostotic convexity have reviewed the medical literature.
osteoma and
RESULTS
A new comprehensive classification for cranial osteomas is proposed: (1) intraparenchymal, (2) dural, (3) skull base, and (4) skull vault. The latter is in turn, subdivided into exostotic and enostotic variants. Three symptom producing enostotic convexity osteotias have been reported in the world literature. We also describe a giant enostotic skull vault osteoma and propose an original surgical technique used to successfully resect this unusual tumor. CONCLUSIONS
Most cranial osteomas are asymptomatic and need not be resected. Those that are symptomatic should be managed properly. Their excision, if not properly performed, may lead to unforeseen cerebral complications. 0 1997 by Elsevier Science Inc. KEY
WORDS
Osteoma,
cranial,
skull neoplasm,
surgery, operative.
A
ccording to Dandy [lo] osteomas are “by far the most common tumors indigenous to the skull.” Courville claims that they are “the commonest space occupying lesions affecting the cranial meninges” [8]. However, symptom producing osteomas of the vault are extremely rare. We present Address reprint requests to: Dr. Fuad S. Haddad, American Beirut, P. 0. Box 113-6044, Beirut, Lebanon. Received June 27, 1996; accepted August 30. 1996. 0 1997 by Elsevier Science Inc. 655 Avenue of the Americas, New York, NY 10010
University
of
a case of a symptom producing giant enostotic osteoma of the skull. We reviewed the world literature and propose a new comprehensive classification. A new surgical approach for the management of such giant lesions is described.
CASE PRESENTATION This Sl-year-old man first presented to our care on March 1, 1989. For 7 years he had suffered from recurrent headaches and seizures. He was well controlled on phenobarbital and diphenylhydantoin. Three months prior to his visit he was involved in a car accident. A few days later, plain skull X rays revealed a large bony tumor arising from the inner table of the right frontal bone and compressing the underlying brain. A computed tomography (CT) scan suggested the diagnosis of an osteoma (Figure 1). The patient was referred for management. The neurologic examination was unremarkable. Surgery was proposed and accepted. The osteoma was in the shape of a truncated cone with its smaller diameter attached to the inner table of the skull and its larger diameter boring into the right frontal lobe. Preoperatively we were fearful the osteoma might be adherent to the underlying dura or might have breached the dura and be in direct contact with the underlying cerebral tissue. These facts prompted us to devise a method to remove the osteoma under direct vision while minimizing the residual skull defect. We elected to pro-
ceed in three steps. The first step was intended to separate the overlying cranium from the underlying osteoma; the second step was devised to uncover the osteoma and surrounding dura by removing a wide bone flap; and the third step consisted of 0090-3019/97/$17.00 PII SOO90-3019(96)004855
144
0
Surg Neurol 1997;48:143-7
Haddad et al
Plain CT scan of the skull revealing the osteoma arising from the inner aspect of the frontal bone.
separating the osteoma from the surrounding tissues under direct vision and removing it in one piece. STEP ONE Step one consisted burr
holes around
of placing
five circumferential
the base of the osteoma.
These
holes were placed about 2 cm away from the margin of the base of the lesion, in order to provide a wide access. We then proceeded to separate the osteoma from the overlying cranium. Three contiguous craniotomy flaps were sufficient for that purpose. These were performed in the following fashion. Gigli saw cuts were performed by directing the saw tangentially and toward the center of the lesion. We stress the fact that at this stage these three flaps were not free flaps but were still connected to the cranium at their periphery. At the end of stage one the osteoma had been completely severed from the overlying cranium. STEP TWO We then proceeded with a Gigli saw to connect the five burr holes in the usual manner, therefore, elevating
three contiguous
STEP THREE The dura was detached the osteoma.
Halfway
free bone flaps (Figure
carefully down
2).
from the walls of
the dura
started
to
become shredded and defective. Further down, the brain and some cortical blood vessels were partially adherent to the side of the osteoma. They had
B (A) Three bone flaps removed over another tumor qtechnique; (an intracerebral osteochondroma) using the same (f3) reconstruction of the bone flap before replacing it over the craniectomy is no loss of bony substance.
defect. Note that there
left an impression in the form of a groove on its surface. These adhesions and blood vessels were gently freed under direct vision and the specimen was gradually mobilized and removed with minimal trauma to the surrounding and underlying brain. The dura was closed and the bone flap reformed using stainless steel wires to hold it together and in place. The specimen was ivory white in appearance and stone hard in consistency measuring 5.7 cm in depth, 6.7 cm in its largest diameter at its free dome, and 5 cm at its attachment to the skull. Its surface was smooth but grooved by cortical vessels (Figure 3). Its histopathology was typical of a compact osteoma. It revealed a uniform histologic appearance and consisted mostly of dense thick trabeculae of lamellar bone. In some areas prominent cement lines were seen. The intervening stroma was sparsely cellular, focally fibrotic, and showed no hematopoetic elements (Figure 4). The patient made an uneventful recovery. The
Cranial Osteoma
Surg Neurol 1997;48:143-7
145
seizures were controlled with phenobarbital, diphenylhydantoin, and primidone. At his last visit, in April 1996, he was symptom free and was still active as a bank clerk.
DISCUSSION Cranial osteomas form a distinct entity and should not be confused with hyperostosis frontalis interna [ 241, osteochondroma, or ossifying fibromas [ 4,18, 26,291. The latter is a manifestation of fibrous dysplasia. Cranial osteomas may be of the spongy or more commonly of the compact solid type. We propose the following clinico-anatomic classification based on the topographic distribution of these tumors. This classification also corresponds to the frequency and symptomatology of such lesions. Four categories are recognized: intraparenchymal, dural, skull base, and skull vault. INTRACRANIAL INTRAPARENCHYMAL OSTEOMAS Intracranial intraparenchymal osteomas, also called “brain calculi” or “brain stones” have no connection to dura or bone. They are the rarest form and often are confused with intracranial calcifications. Of the 22 reported cases [ 17,21,28,30] 11 may be calcifications in an old hematoma, four calcified tuberculomas, and one a calcified abscess. Only six cases may be true osteomas. DURAL OSTEOMAS Dural osteomas are true intracranial neoplasms and not mere calcifications. They affect mainly the falx
1 A photomicrograph of a typical field of the osteoma LI showing dense, thick trabeculae of lamellar bone. H &E, 100x.
and are typically asymptomatic; they are often incidental findings on plain X ray films [13]. They have no bony attachment. In a series of 200 consecutive adult autopsies, 10 patients (5%) had dural osteomas of different sizes, located mostly at the dura-falx junction [ 131. SKULL BASE OSTEOMAS Skull base osteomas have been frequently reported. Their most common location is the frontoethmoidal region. They may also occur in the petrous bone [3,19,31]. Childrey [5] reports the incidence of frontoethmoid osteomas seen on 3510 consecutive skull films as 0.43%. This is in close agreement with the 0.4% incidence reported by Eckel and Palm [12]. Basal osteomas are rarely symptomatic. Their most common clinical presentations are, in decreasing order, headache [2,5,6], invasion and deformity of the orbits [1,25,27], pneumocephalus [1,2,9,1417,291 with possible rhinorrhea and meningitis [2,9], and rarely abscess formation [ 1,221. Both sexes are equally affected and they may occur at any age, their highest incidence being around the age of 20 years
[ 11.
SKULL VAULT OSTEOMAS Skull vault osteomas are less frequent than skull base osteomas. The exostotic form (growing from the outer table) is more common
fq”” ltle1tlti II 9I tlI Q
Gross specimen removed in toto. The origin of the osteoma from the skull is the upper aspect of the
specimen. Note the vascular grooves on its surface.
than the enostotic
form (arising from the inner table and growing intracranially) [ 1,3,11,20,23]. To our knowledge, only five cases of convexity enostotic osteomas were reported. Three cases were symptomatic and suffered from seizures [ 1,3,23], one of whom complained also of headaches [l]. Two cases were asymptomatic [ 11,201. Surgery is the definitive treatment. The surgical management of such a lesion is fraught with danger.
146
H
Haddad et al
Surg Neurol 1997;48:143-7
Skull X ray showing surgery.
the bone flaps 7 years after
Its bony hard consistency makes it piecemeal removal tedious, time consuming [3], and dangerous [ 11. To pull it out of the brain with its attached bony flap, without freeing it from the surrounding brain, is also unwise because of possible adhesions of the tumor to the dura, brain, and blood vessels. The wider free base of the tumor would lacerate the brain. This prompted us to develop the method of excision detailed above. It allows a safe and rapid removal of the tumor and avoids the use of cranioplasty. Plain X rays taken 7 years postoperatively in our patient revealed excellent healing without evidence of recurrence (Figure 5). REFERENCES 1. Arseni C, Ionesco S. Les osteomes craniens. Acta Chirurgic Belgica 1958;2:150-61. 2. Bartlett JR. Intracranial neurological complications of frontal and ethmoidal osteomas. Brit J Surg 1971;58: 607-13. 3. Bhandari YS, Jones RA. Osteoma of the middle cranial fossa. Case report. J Neurosurg 1972;37:610-2. 4. Blitzer A, Post KD, Conley J. Craniofacial resection of ossifying fibromas and osteomas of the sinuses. Arch Otolaryngol Head Neck Surg 1989;115:1112-5.
5. Boysen M. Osteomas of the paranasal sinuses. J Otolaryngol 1978;7:366-70. 6. Childrey JH. Osteoma of the sinuses, the frontal and the sphenoid bone. Report of 15 cases. Arch Otolaryngol 1939;30:63-72. 7. Constantinidis J. Osteome intrathalamique. Psychiat Neurol (Basel) 1967;154:366-72. 8. Courville CB. Pathology of the central nervous system, 2nd ed. Mountain View: Pacific Press Publishing Association, 1945:376, 363-4. 9. Cushing H. Experiences with orbito-ethmoidal osteomata having intracranial complications, with the re port of 4 cases. Surg Gynecol Obstet 1927;44:721-42. 10. Dandy WE. Surgery of the brain. Lewis’ practice of surgery. Hagerstown: W.F. Privy Co, 1945:644-7. 11. Dukes HT, Odom GL. Discrete intradural osteoma. Report of a case. J Neurosurg 1962;19:251-3. 12. Eckel W, Palm D. Statistische und rontgenologishe untersuchungen zur einigen Fragen des Nebenhohlenosteoms. Arch Ohr Nas Kehlkopf heilk 1959; 174:440-57. 13. Fallon MD, Ellerbrake D, Teitelbaum SL. Meningeal osteomas and chronic renal failure. Hum Path01 1982; 13:449-53. 14. Ferlito A, Pesavento G, Recher G, Mingrino S, Visona A, Fiore DL, Macchi C. Intracranial pneumocephalus (secondary to frontoethmoidal osteoma). J Laryngol Otol 1989;103:634-7. 15. Fucci G, Elefante R, Smaltino F. Pneumocefalo secondario ad osteoma fronto-etmoidale. Radio1 Med (Torino) 1984;70:187-9. 16. George J, Merry GS, Jellett LB, Baker JG. Frontal sinus osteoma with complicating intracranial aerocele. Aust N Z J Surg 1990;60:66-8. 17. Hardwidge C, Varma TRK. Intracranial aeroceles as a complication of frontal sinus osteoma. Surg Neuroi 1985;24:401-4. 18. Ito H, Hasegawa T, Hwang WZ, Yamamoto S. Ossifying fibroma of the fronto-ethmoid sinus. Surg Neurol 1984;22:397-402. 19. Karl RD Jr, Hartshorne MF, Cawthon MA, Youngblood LA, Joyce RP, Bunker SR, Howard WH III. Skull scintigraphy-intracranial osteoma. Clin Nucl Med 1983;8:626-7. 20. McClellan RL, Eisenberg RL, Givanani VL. Routine CT screening of psychiatry inpatients. Radiology 1988; 169:99-100. 21. Pilcher C. Bony intracranial tumors, with report of three cases. South Med J 1938;31:613-9. 22. Poser R. Frontal lobe abscess as a complication of frontal sinus osteoma. Laryng-rhinol-otol 1988;67: 136-7. 23. Rand CW. Osteoma of the skull: report of 2 cases one being associated with a large intracranial endothelioma. Arch Surg (Chicago) 1923;6:573-86. 24. Ritvo M. Roentgen diagnosis of diseases of the skull. In: Annals of roentgenology, vol 19. New York: Paul B. Hoeber, 1949:330-2. 25. Sadry F, Hessler C, Garcia J. The potential aggressiveness of sinus osteomas. A report of two cases. Skeletal Radio1 1988;17:427-30. 26. Scott M, Peale AR, Croissant PD. Intracranial midline anterior fossae ossifying fibroma invading orbits, paranasal sinuses, and right maxillary antrum. J Neurosurg 1971;34:827-31.
Cranial Osteoma
Surg Neurol 147 1997;48:143-7
27. Taptas JN, Kordiolis N, Liarikos S. Complications orbitaires et endocraniennes des osteomes des sinus paranasaux. Neurochirurgie 1979;25:185-8. 28. Tiberin P, Beller AJ. Observations on so-called brain stones or cerebral calculi. Neurology (Mineapolis) 1963;13:464-76. 29. Tomita T, Huvos AG, Shah J, Sundaresan N. Giant ossifying fibroma of the nasal cavity with intracranial extension. Acta Neurochir (Wien) 1981;56:65-71. 30. Vakaet A, De Reuck J, Thiery E, Vander Eecken H. Intracerebral osteoma: a clinico- pathologic and neuropsychologic case study. Child’s Brain 1983;lO: 281-5. 31. Van Dellen JR. A mastoid osteoma causing intracranial complications. A case report. S Afr Med J 1977; 51:597-8. 32. Vandenberg Jr. HJ, Coley BL. Primary tumors of the cranial bones. Surg Gynecol Obstet 1950;90:602-12.
especially in the skull base. Those in the skull vault are less frequent, the most well-known being the exostotic form sometimes associated with Gardner’s syndrome [ 11. The enostotic form reported in this paper is very rare. The reminder of the classification system for osteomas is useful, but the most interesting point in this paper is the surgical approach described by the authors. The danger of pulling it from the brain is obvious, as with some convexity meningiomas with bony invasion. The authors’ approach should be kept in mind. Jacques Brotchi, M.D., Ph.D. Brussels, Belgium REFERENCE
COMMENTARY
Haddad et al present a nice case of enostotic skull vault osteoma. Cranial osteomas are quite frequent,
1. Gardner EJ. Follow-up study of a family group exhibiting dominant inheritance for a syndrome including intestinal polyps, osteomas, fibromas and epidermal cysts. Am J Hum Genet 1962;14:376-90.
P
EOPLE ARE ALWAYS BLAMING THEIR CIRCUMSTANCES FOR WHAT THEY ARE. 1 DON’T BELIEVE IN CIRCUMSTANCES. THE PEOPLE WHO GET ON IN THIS WORLD ARE THE PEOPLE WHO GET UP AND LOOK FOR THE CIRCUMSTANCES THEY WANT, AND, IF THEY CAN’T FIND THEM, MAKE THEM. -GEORGE “MRS.
BERNARD WARREN’S
SHAW (1856-l PROFESSION,”
950) ACT II
CRANIAL OSTEOMAS: THEIR CLASSIFICATION AND MANAGEMENT REPORT ON A GIANT THE LITERATURE
OSTEOMA
AND
REVIEW
OF
Fuad S. Haddad, M.D., F.R.C.S.(C.), F.A.C.S.,* Georges F. Haddad, M.D., F.R.C.S.(C.),* and Ghazi Zaatari, M.D.t
*Division of Neurosurgery, TDepartment of Pathology, American University of Beirut, Beirut, Lebanon
Haddad FS, Haddad GF, Zaatari C. Cranial osteomas: their classification and management. Report on a giant osteoma and review of the literature. Surg Neural 1997;48:143-7. BACKGROUND
Cranial osteomas are regarded by some as very common; yet their classification, symptomatology, and management have been neglected. METHODS
We report on a giant enostotic convexity have reviewed the medical literature.
osteoma and
RESULTS
A new comprehensive classification for cranial osteomas is proposed: (1) intraparenchymal, (2) dural, (3) skull base, and (4) skull vault. The latter is in turn, subdivided into exostotic and enostotic variants. Three symptom producing enostotic convexity osteotias have been reported in the world literature. We also describe a giant enostotic skull vault osteoma and propose an original surgical technique used to successfully resect this unusual tumor. CONCLUSIONS
Most cranial osteomas are asymptomatic and need not be resected. Those that are symptomatic should be managed properly. Their excision, if not properly performed, may lead to unforeseen cerebral complications. 0 1997 by Elsevier Science Inc. KEY
WORDS
Osteoma,
cranial,
skull neoplasm,
surgery, operative.
A
ccording to Dandy [lo] osteomas are “by far the most common tumors indigenous to the skull.” Courville claims that they are “the commonest space occupying lesions affecting the cranial meninges” [8]. However, symptom producing osteomas of the vault are extremely rare. We present Address reprint requests to: Dr. Fuad S. Haddad, American Beirut, P. 0. Box 113-6044, Beirut, Lebanon. Received June 27, 1996; accepted August 30. 1996. 0 1997 by Elsevier Science Inc. 655 Avenue of the Americas, New York, NY 10010
University
of
a case of a symptom producing giant enostotic osteoma of the skull. We reviewed the world literature and propose a new comprehensive classification. A new surgical approach for the management of such giant lesions is described.
CASE PRESENTATION This Sl-year-old man first presented to our care on March 1, 1989. For 7 years he had suffered from recurrent headaches and seizures. He was well controlled on phenobarbital and diphenylhydantoin. Three months prior to his visit he was involved in a car accident. A few days later, plain skull X rays revealed a large bony tumor arising from the inner table of the right frontal bone and compressing the underlying brain. A computed tomography (CT) scan suggested the diagnosis of an osteoma (Figure 1). The patient was referred for management. The neurologic examination was unremarkable. Surgery was proposed and accepted. The osteoma was in the shape of a truncated cone with its smaller diameter attached to the inner table of the skull and its larger diameter boring into the right frontal lobe. Preoperatively we were fearful the osteoma might be adherent to the underlying dura or might have breached the dura and be in direct contact with the underlying cerebral tissue. These facts prompted us to devise a method to remove the osteoma under direct vision while minimizing the residual skull defect. We elected to pro-
ceed in three steps. The first step was intended to separate the overlying cranium from the underlying osteoma; the second step was devised to uncover the osteoma and surrounding dura by removing a wide bone flap; and the third step consisted of 0090-3019/97/$17.00 PII SOO90-3019(96)004855
144
0
Surg Neurol 1997;48:143-7
Haddad et al
Plain CT scan of the skull revealing the osteoma arising from the inner aspect of the frontal bone.
separating the osteoma from the surrounding tissues under direct vision and removing it in one piece. STEP ONE Step one consisted burr
holes around
of placing
five circumferential
the base of the osteoma.
These
holes were placed about 2 cm away from the margin of the base of the lesion, in order to provide a wide access. We then proceeded to separate the osteoma from the overlying cranium. Three contiguous craniotomy flaps were sufficient for that purpose. These were performed in the following fashion. Gigli saw cuts were performed by directing the saw tangentially and toward the center of the lesion. We stress the fact that at this stage these three flaps were not free flaps but were still connected to the cranium at their periphery. At the end of stage one the osteoma had been completely severed from the overlying cranium. STEP TWO We then proceeded with a Gigli saw to connect the five burr holes in the usual manner, therefore, elevating
three contiguous
STEP THREE The dura was detached the osteoma.
Halfway
free bone flaps (Figure
carefully down
2).
from the walls of
the dura
started
to
become shredded and defective. Further down, the brain and some cortical blood vessels were partially adherent to the side of the osteoma. They had
B (A) Three bone flaps removed over another tumor qtechnique; (an intracerebral osteochondroma) using the same (f3) reconstruction of the bone flap before replacing it over the craniectomy is no loss of bony substance.
defect. Note that there
left an impression in the form of a groove on its surface. These adhesions and blood vessels were gently freed under direct vision and the specimen was gradually mobilized and removed with minimal trauma to the surrounding and underlying brain. The dura was closed and the bone flap reformed using stainless steel wires to hold it together and in place. The specimen was ivory white in appearance and stone hard in consistency measuring 5.7 cm in depth, 6.7 cm in its largest diameter at its free dome, and 5 cm at its attachment to the skull. Its surface was smooth but grooved by cortical vessels (Figure 3). Its histopathology was typical of a compact osteoma. It revealed a uniform histologic appearance and consisted mostly of dense thick trabeculae of lamellar bone. In some areas prominent cement lines were seen. The intervening stroma was sparsely cellular, focally fibrotic, and showed no hematopoetic elements (Figure 4). The patient made an uneventful recovery. The
Cranial Osteoma
Surg Neurol 1997;48:143-7
145
seizures were controlled with phenobarbital, diphenylhydantoin, and primidone. At his last visit, in April 1996, he was symptom free and was still active as a bank clerk.
DISCUSSION Cranial osteomas form a distinct entity and should not be confused with hyperostosis frontalis interna [ 241, osteochondroma, or ossifying fibromas [ 4,18, 26,291. The latter is a manifestation of fibrous dysplasia. Cranial osteomas may be of the spongy or more commonly of the compact solid type. We propose the following clinico-anatomic classification based on the topographic distribution of these tumors. This classification also corresponds to the frequency and symptomatology of such lesions. Four categories are recognized: intraparenchymal, dural, skull base, and skull vault. INTRACRANIAL INTRAPARENCHYMAL OSTEOMAS Intracranial intraparenchymal osteomas, also called “brain calculi” or “brain stones” have no connection to dura or bone. They are the rarest form and often are confused with intracranial calcifications. Of the 22 reported cases [ 17,21,28,30] 11 may be calcifications in an old hematoma, four calcified tuberculomas, and one a calcified abscess. Only six cases may be true osteomas. DURAL OSTEOMAS Dural osteomas are true intracranial neoplasms and not mere calcifications. They affect mainly the falx
1 A photomicrograph of a typical field of the osteoma LI showing dense, thick trabeculae of lamellar bone. H &E, 100x.
and are typically asymptomatic; they are often incidental findings on plain X ray films [13]. They have no bony attachment. In a series of 200 consecutive adult autopsies, 10 patients (5%) had dural osteomas of different sizes, located mostly at the dura-falx junction [ 131. SKULL BASE OSTEOMAS Skull base osteomas have been frequently reported. Their most common location is the frontoethmoidal region. They may also occur in the petrous bone [3,19,31]. Childrey [5] reports the incidence of frontoethmoid osteomas seen on 3510 consecutive skull films as 0.43%. This is in close agreement with the 0.4% incidence reported by Eckel and Palm [12]. Basal osteomas are rarely symptomatic. Their most common clinical presentations are, in decreasing order, headache [2,5,6], invasion and deformity of the orbits [1,25,27], pneumocephalus [1,2,9,1417,291 with possible rhinorrhea and meningitis [2,9], and rarely abscess formation [ 1,221. Both sexes are equally affected and they may occur at any age, their highest incidence being around the age of 20 years
[ 11.
SKULL VAULT OSTEOMAS Skull vault osteomas are less frequent than skull base osteomas. The exostotic form (growing from the outer table) is more common
fq”” ltle1tlti II 9I tlI Q
Gross specimen removed in toto. The origin of the osteoma from the skull is the upper aspect of the
specimen. Note the vascular grooves on its surface.
than the enostotic
form (arising from the inner table and growing intracranially) [ 1,3,11,20,23]. To our knowledge, only five cases of convexity enostotic osteomas were reported. Three cases were symptomatic and suffered from seizures [ 1,3,23], one of whom complained also of headaches [l]. Two cases were asymptomatic [ 11,201. Surgery is the definitive treatment. The surgical management of such a lesion is fraught with danger.
146
H
Haddad et al
Surg Neurol 1997;48:143-7
Skull X ray showing surgery.
the bone flaps 7 years after
Its bony hard consistency makes it piecemeal removal tedious, time consuming [3], and dangerous [ 11. To pull it out of the brain with its attached bony flap, without freeing it from the surrounding brain, is also unwise because of possible adhesions of the tumor to the dura, brain, and blood vessels. The wider free base of the tumor would lacerate the brain. This prompted us to develop the method of excision detailed above. It allows a safe and rapid removal of the tumor and avoids the use of cranioplasty. Plain X rays taken 7 years postoperatively in our patient revealed excellent healing without evidence of recurrence (Figure 5). REFERENCES 1. Arseni C, Ionesco S. Les osteomes craniens. Acta Chirurgic Belgica 1958;2:150-61. 2. Bartlett JR. Intracranial neurological complications of frontal and ethmoidal osteomas. Brit J Surg 1971;58: 607-13. 3. Bhandari YS, Jones RA. Osteoma of the middle cranial fossa. Case report. J Neurosurg 1972;37:610-2. 4. Blitzer A, Post KD, Conley J. Craniofacial resection of ossifying fibromas and osteomas of the sinuses. Arch Otolaryngol Head Neck Surg 1989;115:1112-5.
5. Boysen M. Osteomas of the paranasal sinuses. J Otolaryngol 1978;7:366-70. 6. Childrey JH. Osteoma of the sinuses, the frontal and the sphenoid bone. Report of 15 cases. Arch Otolaryngol 1939;30:63-72. 7. Constantinidis J. Osteome intrathalamique. Psychiat Neurol (Basel) 1967;154:366-72. 8. Courville CB. Pathology of the central nervous system, 2nd ed. Mountain View: Pacific Press Publishing Association, 1945:376, 363-4. 9. Cushing H. Experiences with orbito-ethmoidal osteomata having intracranial complications, with the re port of 4 cases. Surg Gynecol Obstet 1927;44:721-42. 10. Dandy WE. Surgery of the brain. Lewis’ practice of surgery. Hagerstown: W.F. Privy Co, 1945:644-7. 11. Dukes HT, Odom GL. Discrete intradural osteoma. Report of a case. J Neurosurg 1962;19:251-3. 12. Eckel W, Palm D. Statistische und rontgenologishe untersuchungen zur einigen Fragen des Nebenhohlenosteoms. Arch Ohr Nas Kehlkopf heilk 1959; 174:440-57. 13. Fallon MD, Ellerbrake D, Teitelbaum SL. Meningeal osteomas and chronic renal failure. Hum Path01 1982; 13:449-53. 14. Ferlito A, Pesavento G, Recher G, Mingrino S, Visona A, Fiore DL, Macchi C. Intracranial pneumocephalus (secondary to frontoethmoidal osteoma). J Laryngol Otol 1989;103:634-7. 15. Fucci G, Elefante R, Smaltino F. Pneumocefalo secondario ad osteoma fronto-etmoidale. Radio1 Med (Torino) 1984;70:187-9. 16. George J, Merry GS, Jellett LB, Baker JG. Frontal sinus osteoma with complicating intracranial aerocele. Aust N Z J Surg 1990;60:66-8. 17. Hardwidge C, Varma TRK. Intracranial aeroceles as a complication of frontal sinus osteoma. Surg Neuroi 1985;24:401-4. 18. Ito H, Hasegawa T, Hwang WZ, Yamamoto S. Ossifying fibroma of the fronto-ethmoid sinus. Surg Neurol 1984;22:397-402. 19. Karl RD Jr, Hartshorne MF, Cawthon MA, Youngblood LA, Joyce RP, Bunker SR, Howard WH III. Skull scintigraphy-intracranial osteoma. Clin Nucl Med 1983;8:626-7. 20. McClellan RL, Eisenberg RL, Givanani VL. Routine CT screening of psychiatry inpatients. Radiology 1988; 169:99-100. 21. Pilcher C. Bony intracranial tumors, with report of three cases. South Med J 1938;31:613-9. 22. Poser R. Frontal lobe abscess as a complication of frontal sinus osteoma. Laryng-rhinol-otol 1988;67: 136-7. 23. Rand CW. Osteoma of the skull: report of 2 cases one being associated with a large intracranial endothelioma. Arch Surg (Chicago) 1923;6:573-86. 24. Ritvo M. Roentgen diagnosis of diseases of the skull. In: Annals of roentgenology, vol 19. New York: Paul B. Hoeber, 1949:330-2. 25. Sadry F, Hessler C, Garcia J. The potential aggressiveness of sinus osteomas. A report of two cases. Skeletal Radio1 1988;17:427-30. 26. Scott M, Peale AR, Croissant PD. Intracranial midline anterior fossae ossifying fibroma invading orbits, paranasal sinuses, and right maxillary antrum. J Neurosurg 1971;34:827-31.
Cranial Osteoma
Surg Neurol 147 1997;48:143-7
27. Taptas JN, Kordiolis N, Liarikos S. Complications orbitaires et endocraniennes des osteomes des sinus paranasaux. Neurochirurgie 1979;25:185-8. 28. Tiberin P, Beller AJ. Observations on so-called brain stones or cerebral calculi. Neurology (Mineapolis) 1963;13:464-76. 29. Tomita T, Huvos AG, Shah J, Sundaresan N. Giant ossifying fibroma of the nasal cavity with intracranial extension. Acta Neurochir (Wien) 1981;56:65-71. 30. Vakaet A, De Reuck J, Thiery E, Vander Eecken H. Intracerebral osteoma: a clinico- pathologic and neuropsychologic case study. Child’s Brain 1983;lO: 281-5. 31. Van Dellen JR. A mastoid osteoma causing intracranial complications. A case report. S Afr Med J 1977; 51:597-8. 32. Vandenberg Jr. HJ, Coley BL. Primary tumors of the cranial bones. Surg Gynecol Obstet 1950;90:602-12.
especially in the skull base. Those in the skull vault are less frequent, the most well-known being the exostotic form sometimes associated with Gardner’s syndrome [ 11. The enostotic form reported in this paper is very rare. The reminder of the classification system for osteomas is useful, but the most interesting point in this paper is the surgical approach described by the authors. The danger of pulling it from the brain is obvious, as with some convexity meningiomas with bony invasion. The authors’ approach should be kept in mind. Jacques Brotchi, M.D., Ph.D. Brussels, Belgium REFERENCE
COMMENTARY
Haddad et al present a nice case of enostotic skull vault osteoma. Cranial osteomas are quite frequent,
1. Gardner EJ. Follow-up study of a family group exhibiting dominant inheritance for a syndrome including intestinal polyps, osteomas, fibromas and epidermal cysts. Am J Hum Genet 1962;14:376-90.
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EOPLE ARE ALWAYS BLAMING THEIR CIRCUMSTANCES FOR WHAT THEY ARE. 1 DON’T BELIEVE IN CIRCUMSTANCES. THE PEOPLE WHO GET ON IN THIS WORLD ARE THE PEOPLE WHO GET UP AND LOOK FOR THE CIRCUMSTANCES THEY WANT, AND, IF THEY CAN’T FIND THEM, MAKE THEM. -GEORGE “MRS.
BERNARD WARREN’S
SHAW (1856-l PROFESSION,”
950) ACT II