Osteoma of the ethmofrontal sinus Case report ADEBAYO A. OLUMIDE,M.B.B.S., F.R.C.S. (Eo.), ADEBAYO A. FAJEMISIN,M.B., Cn.B., F.R.C.S. (El).), AND ADELOLA ADELOYE,M.B.B.S., M.R.C.P. (ED.), F.R.C.S. (ENC,)
Neurosurgery Unit, Department of Surgery and Department of Otorhinolaryngology, University of Ibadan, Nigeria v' An unusually large osteoma of the ethmofrontal sinus is described, and the related literature is briefly reviewed. The authors believe frontal exploration is necessary in cases of extensive osteomas of the frontal sinus. KEY WORDS
9
osteoma
9 frontal sinus
O
STEOMAS of the paranasal sinuses are comparatively uncommon. Most cases are seen by otorhinolaryngologists, only a few come to the attention of neurosurgeons because of possible or established intracranial complications. Mehta and Grewal 1~ reported 50 osteomas in 5086 patients complaining of sinusitis. Most of the paranasal osteomas seen in Ibadan are too small to warrant surgical intervention. We are reporting this case not only because of the enormous size of the osteoma, but also to stress the need for surgical exploration. Case Report
A 16-year-old boy was admitted to the University College Hospital, Ibadan, Nigeria, in August, 1973, with left supraorbital swelling. Eighteen months prior to admission, a stone thrown by a schoolmate hit him in the left supraorbital region. There was slight bruising over the site of impact and iodine solution was applied locally. He also
J. Neurosurg. / Volume 42 / March, 1975
had epistaxis for about 5 days, followed by a left nasal discharge. Soon after the injury, a painful swelling appeared in the left supraorbital region. The swelling had steadily increased in size, while the other symptoms had disappeared. Examination. The patient had a stony hard swelling 6 cm in diameter over the left supraorbital region. The swelling was fixed to the underlying bone but was not attached to the overlying skin; it was slightly tender to touch, but not warm or indurated. He had no other swellings on the scalp, face, or neck. No neurological deficit was found, and the other systems were normal. Plain skull x-rays showed a dense opacity which appeared to fill the frontal sinuses and extend into the left ethmoidal sinus (Fig. 1). A left carotid angiogram was normal. The patient had a packed cell volume (PCV) of 42%, white cell count of 3500/ram 3, and genotype AA. Serum electrolytes and urea were within normal limits. 343
A. A. O l u m i d e , A. A. F a j e m i s i n
F~o. 1. Plain x-ray films of the skull showing the ethmofrontal osteoma. jection. Right: Lateral projection.
Operation. A bifrontal craniectomy was carried out through a bicoronal flap. This was necessary because the osteoma had eroded through the frontal bone. A stony hard m~iss occupied both frontal sinuses, particularly on the left, where the mass extended down into the ethmoid sinus and the upper part of the nasal cavity. The superomedial wall of the left orbit was markedly thinned, with multiple minute mucoceles. The dura mater was intact but considerably compressed by the tumor. The edge of the osteoma was clearly defined, and was attached inferiorly by a pedicle. The tumor was delivered intact by gentle rocking which severed the pedicle. This created a huge frontonasal defect, but bleeding was minimal. A frontonasal drainage tube was inserted and removed after 48 hours. The pericranium was approximated and the skin closed in one layer with silk. We made no attempt at cranioplasty. The postoperative course was uneventful. The scalp wound healed well, but the patient was left with a frontal defect. He is to have an acrylic cranioplasty 3 months after operation. Pathological Examination. The osteoma weighed 150 gm, and was 10 cm long, 8 cm wide, and 5 cm thick. It was a yellowish-white multilobulated rock-hard mass, found on section to be completely calcified; this gave it a marble-like appearance. Microscopy showed the wide irregular trabeculae of mature bone that formed the whole of the mass (Fig. 2), and showed little evidence of new bone formation. The ultratrabecular tissue was sparse and vascular. 344
a n d A. A. A d e l o y e
Left: Anteroposterior pro-
Discussion Most of the reports on osteomas of the paranasal sinuses have been made on small series 1'4'" or single cases? ,x~ A few theories have been offered on the genesis of osteomas. Arnold 3 suggested that errors of growth are more likely to occur at the junction of two bones, one of which is formed in membrane (frontal) and the other in cartilage (ethmoid). Ossification of the fetal cartilage at the junction of the ethmoid and frontal sinuses therefore results in osteomas. Dolbeau 7 declared that osteomata arose from mucoperiosteum lining the wall of the parent sinus. Fetiso~ thought tumor iniiated from a section of the periosteum that split from a bone at an early age and developed into a tumor under the influence of irritation. The role of trauma in the genesis of osteomas was first suggested by Cushing ~ and highlighted in the case reports of Appalanarasayya, et al.,2 and Cassady and Alexander? Thus the history of trauma in our patient may be etiologically significant. The male preponderance reported in most series has been attributed by some to the greater liability to trauma in males and aJso to the larger size of their sinuses. Dowling8 has suggested infection as an important etiological factor in osteoma formation. According to Mehta and Grewal, 1~ the frontal sinus is the predominant site (96%) for the occurrence of osteoma, with negligible involvement of the ethmoidal (2%), maxillary
J. Neurosurg. / Volume 42 / March. 1975
Osteoma of the ethmofrontal sinus (2%), and the sphenoid sinuses. Of the five cases of osteoma of the paranasal sinuses described by Rowbotham, 11 four were in the frontal sinus. The age incidence is variable; 80% of Mehta and Grewal's cases occurred in patients from 10 to 30 years old, and the ages of Rowbotham's cases ranged from 18 to 58. Osteomas are benign, slow-growing tumors, of three main types. The usual variety is ivory hard, as in our case; less common is the compact or solid type which has normal bone architecture, while the least common is the spongy and most immature type. Histologically, the tumors may be composed of pure fibrous tissue or pure bone. Most are a mixture of the two tissues. The majority of osteomas are asymptomatic. Depending on the direction of the gcowth, their common clinical features includ~ pain, deformity, visual disturbance, and infection. Bartlett's 4 excellent paper described the various intracranial neurological complicatioas in five patients with osteomas involving the ethmofrontal sinus. Fistulous connections between the nasal passages and the intracranial cavity led to the formation of an aerocele in two patients and meningitis in one. Hemiplegia, epilepsy, irritability, and drowsiness were the common neurological complications. Our patient had no neurological signs or complications; however, we believe that in time he would have developed neurological problems, as the dura mater was already considerably compressed by the osteoma. Radiological examination remains the main diagnostic tool. Appalanarasayya, et al., 2 recommended orbitography with contrast medium or air in patients with proptosis. Andrew 1 has suggested that small osteomas found in routine radiological examinations should be kept under observation, while those causing symptoms or obvious obstruction of the frontonasal duct should be excised through an external approach. He also recommended prompt excision through a frontal craniotomy of an osteoma obliterating its parent sinus or extending beyond the sinus. On the whole, the results of surgery in reported cases of frontonasal osteoma have been good. 1,2,' Our case report further emphasizes the benefit of craniotomy in treating this disease. J. Neurosurg. / Volume 42 / March, 1975
Fro. 2. Histological section of the tumor specimen showing wide, irregular, and sparse trabeculae of mature bone. H & E, • 100. References 1. Andrew J: Osteomata of the paranasal sinuses. Br J Surg 43:489-497, 1956 2. Appalanarasayya K, Murthy ASR, Viswanath CK, et al: Osteoma involving the orbit. Case report and review of the literature. Int Surg 54:449-453, 1970 3. Arnold J: Zwei Osteoma der Stirnhoble. Virchows Arch [Pathol Anat] 57:145-163, 1873 4. Bartlett JR: Intracranial neurological complications of frontal and ethmoidal osteomas. Br J Surg 58:607-613, 1971 5. Cassady CL, Alexander FW: Removal of a large fronto-ethmoidal osteoma. A case report. Arch Otolaryngol 93:81-82, 1971 6. Cushing H: Experiences with orbitalethmoidal osteomata having intracranial complications with report of four cases. Surg Gynec Obstet 44:721-742, 1927 7. Dolbeau M: Mere Acad Med 30:1, 1871 8. DoMing JR: Osteoma of the frontal sinus. Report of five cases. Arch Otolaryngol 41:99-108, 1945 9. Fetisoff AG: Pathogenesis of osteoma of nasal accessory sinuses. Ann Otol Rhinol Laryngol 38:404-420, 1929 10. Mehta BS, Grewal GS: Osteoma of the paranasal sinuses along with a case report of an orbito-ethmoidal osteoma. J Laryngol 77:601-610, 1963 11. Rowbotham GF: Neoplasms that grow from the bone-forming elements of the skull. A survey of 20 cases. Br J Surg 45:123-134, 1957 Address reprint requests to: Adebayo A. Olumide, F.R.C.S., Neurosurgery Unit, Department of Surgery, University of Ihadan, Nigeria.
345
Neurosurgery Unit, Department of Surgery and Department of Otorhinolaryngology, University of Ibadan, Nigeria v' An unusually large osteoma of the ethmofrontal sinus is described, and the related literature is briefly reviewed. The authors believe frontal exploration is necessary in cases of extensive osteomas of the frontal sinus. KEY WORDS
9
osteoma
9 frontal sinus
O
STEOMAS of the paranasal sinuses are comparatively uncommon. Most cases are seen by otorhinolaryngologists, only a few come to the attention of neurosurgeons because of possible or established intracranial complications. Mehta and Grewal 1~ reported 50 osteomas in 5086 patients complaining of sinusitis. Most of the paranasal osteomas seen in Ibadan are too small to warrant surgical intervention. We are reporting this case not only because of the enormous size of the osteoma, but also to stress the need for surgical exploration. Case Report
A 16-year-old boy was admitted to the University College Hospital, Ibadan, Nigeria, in August, 1973, with left supraorbital swelling. Eighteen months prior to admission, a stone thrown by a schoolmate hit him in the left supraorbital region. There was slight bruising over the site of impact and iodine solution was applied locally. He also
J. Neurosurg. / Volume 42 / March, 1975
had epistaxis for about 5 days, followed by a left nasal discharge. Soon after the injury, a painful swelling appeared in the left supraorbital region. The swelling had steadily increased in size, while the other symptoms had disappeared. Examination. The patient had a stony hard swelling 6 cm in diameter over the left supraorbital region. The swelling was fixed to the underlying bone but was not attached to the overlying skin; it was slightly tender to touch, but not warm or indurated. He had no other swellings on the scalp, face, or neck. No neurological deficit was found, and the other systems were normal. Plain skull x-rays showed a dense opacity which appeared to fill the frontal sinuses and extend into the left ethmoidal sinus (Fig. 1). A left carotid angiogram was normal. The patient had a packed cell volume (PCV) of 42%, white cell count of 3500/ram 3, and genotype AA. Serum electrolytes and urea were within normal limits. 343
A. A. O l u m i d e , A. A. F a j e m i s i n
F~o. 1. Plain x-ray films of the skull showing the ethmofrontal osteoma. jection. Right: Lateral projection.
Operation. A bifrontal craniectomy was carried out through a bicoronal flap. This was necessary because the osteoma had eroded through the frontal bone. A stony hard m~iss occupied both frontal sinuses, particularly on the left, where the mass extended down into the ethmoid sinus and the upper part of the nasal cavity. The superomedial wall of the left orbit was markedly thinned, with multiple minute mucoceles. The dura mater was intact but considerably compressed by the tumor. The edge of the osteoma was clearly defined, and was attached inferiorly by a pedicle. The tumor was delivered intact by gentle rocking which severed the pedicle. This created a huge frontonasal defect, but bleeding was minimal. A frontonasal drainage tube was inserted and removed after 48 hours. The pericranium was approximated and the skin closed in one layer with silk. We made no attempt at cranioplasty. The postoperative course was uneventful. The scalp wound healed well, but the patient was left with a frontal defect. He is to have an acrylic cranioplasty 3 months after operation. Pathological Examination. The osteoma weighed 150 gm, and was 10 cm long, 8 cm wide, and 5 cm thick. It was a yellowish-white multilobulated rock-hard mass, found on section to be completely calcified; this gave it a marble-like appearance. Microscopy showed the wide irregular trabeculae of mature bone that formed the whole of the mass (Fig. 2), and showed little evidence of new bone formation. The ultratrabecular tissue was sparse and vascular. 344
a n d A. A. A d e l o y e
Left: Anteroposterior pro-
Discussion Most of the reports on osteomas of the paranasal sinuses have been made on small series 1'4'" or single cases? ,x~ A few theories have been offered on the genesis of osteomas. Arnold 3 suggested that errors of growth are more likely to occur at the junction of two bones, one of which is formed in membrane (frontal) and the other in cartilage (ethmoid). Ossification of the fetal cartilage at the junction of the ethmoid and frontal sinuses therefore results in osteomas. Dolbeau 7 declared that osteomata arose from mucoperiosteum lining the wall of the parent sinus. Fetiso~ thought tumor iniiated from a section of the periosteum that split from a bone at an early age and developed into a tumor under the influence of irritation. The role of trauma in the genesis of osteomas was first suggested by Cushing ~ and highlighted in the case reports of Appalanarasayya, et al.,2 and Cassady and Alexander? Thus the history of trauma in our patient may be etiologically significant. The male preponderance reported in most series has been attributed by some to the greater liability to trauma in males and aJso to the larger size of their sinuses. Dowling8 has suggested infection as an important etiological factor in osteoma formation. According to Mehta and Grewal, 1~ the frontal sinus is the predominant site (96%) for the occurrence of osteoma, with negligible involvement of the ethmoidal (2%), maxillary
J. Neurosurg. / Volume 42 / March. 1975
Osteoma of the ethmofrontal sinus (2%), and the sphenoid sinuses. Of the five cases of osteoma of the paranasal sinuses described by Rowbotham, 11 four were in the frontal sinus. The age incidence is variable; 80% of Mehta and Grewal's cases occurred in patients from 10 to 30 years old, and the ages of Rowbotham's cases ranged from 18 to 58. Osteomas are benign, slow-growing tumors, of three main types. The usual variety is ivory hard, as in our case; less common is the compact or solid type which has normal bone architecture, while the least common is the spongy and most immature type. Histologically, the tumors may be composed of pure fibrous tissue or pure bone. Most are a mixture of the two tissues. The majority of osteomas are asymptomatic. Depending on the direction of the gcowth, their common clinical features includ~ pain, deformity, visual disturbance, and infection. Bartlett's 4 excellent paper described the various intracranial neurological complicatioas in five patients with osteomas involving the ethmofrontal sinus. Fistulous connections between the nasal passages and the intracranial cavity led to the formation of an aerocele in two patients and meningitis in one. Hemiplegia, epilepsy, irritability, and drowsiness were the common neurological complications. Our patient had no neurological signs or complications; however, we believe that in time he would have developed neurological problems, as the dura mater was already considerably compressed by the osteoma. Radiological examination remains the main diagnostic tool. Appalanarasayya, et al., 2 recommended orbitography with contrast medium or air in patients with proptosis. Andrew 1 has suggested that small osteomas found in routine radiological examinations should be kept under observation, while those causing symptoms or obvious obstruction of the frontonasal duct should be excised through an external approach. He also recommended prompt excision through a frontal craniotomy of an osteoma obliterating its parent sinus or extending beyond the sinus. On the whole, the results of surgery in reported cases of frontonasal osteoma have been good. 1,2,' Our case report further emphasizes the benefit of craniotomy in treating this disease. J. Neurosurg. / Volume 42 / March, 1975
Fro. 2. Histological section of the tumor specimen showing wide, irregular, and sparse trabeculae of mature bone. H & E, • 100. References 1. Andrew J: Osteomata of the paranasal sinuses. Br J Surg 43:489-497, 1956 2. Appalanarasayya K, Murthy ASR, Viswanath CK, et al: Osteoma involving the orbit. Case report and review of the literature. Int Surg 54:449-453, 1970 3. Arnold J: Zwei Osteoma der Stirnhoble. Virchows Arch [Pathol Anat] 57:145-163, 1873 4. Bartlett JR: Intracranial neurological complications of frontal and ethmoidal osteomas. Br J Surg 58:607-613, 1971 5. Cassady CL, Alexander FW: Removal of a large fronto-ethmoidal osteoma. A case report. Arch Otolaryngol 93:81-82, 1971 6. Cushing H: Experiences with orbitalethmoidal osteomata having intracranial complications with report of four cases. Surg Gynec Obstet 44:721-742, 1927 7. Dolbeau M: Mere Acad Med 30:1, 1871 8. DoMing JR: Osteoma of the frontal sinus. Report of five cases. Arch Otolaryngol 41:99-108, 1945 9. Fetisoff AG: Pathogenesis of osteoma of nasal accessory sinuses. Ann Otol Rhinol Laryngol 38:404-420, 1929 10. Mehta BS, Grewal GS: Osteoma of the paranasal sinuses along with a case report of an orbito-ethmoidal osteoma. J Laryngol 77:601-610, 1963 11. Rowbotham GF: Neoplasms that grow from the bone-forming elements of the skull. A survey of 20 cases. Br J Surg 45:123-134, 1957 Address reprint requests to: Adebayo A. Olumide, F.R.C.S., Neurosurgery Unit, Department of Surgery, University of Ihadan, Nigeria.
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