Surgical Management of a Massive Frontal Bone Hemangioma: Case Report.

Intraosseous hemangiomas are rare, benign tumors that can arise from the calvarium. These lesions often invade the outer table of the skull, but typically spare the inner table and intracranial structures. En bloc surgical resection is the standard treatment for intraosseous hemangiomas. However, a piecemeal resection may be required to safely remove the tumor in cases involving the inner table to protect the underlying brain parenchyma and vascular structures. Proper reconstruction is critical to optimize the cosmetic outcome, and a staged procedure allowing implantation of a custom-made implant can be considered for large lesions involving the forehead. We present a case of a patient with a large frontal intraosseous hemangioma with intradural involvement to highlight the surgical nuances of resection and review the existing literature regarding optimal management of these patients. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. ( https://creativecommons.org/licenses/by-nc-nd/4.0/ ).

Importance

Intraosseous cavernous hemangiomas are rare, benign tumors. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 These lesions represent 0.2% of primary cranial bone tumors and predominantly present as solitary lesions in the frontal or parietal bone. 1 2 3 4 5 7 8 9 10 12 13 14 15 16 17 19 20 21 22 23 24 25 26 27 28 29 30 31 32 They often involve the outer table and diploic space, while sparing the inner table, and are treated with en bloc surgical resection and cranioplasty. 2 13 14 20 Few reports have described intraosseous cavernous hemangiomas extending beyond the inner table or with substantial involvement of the bifrontal calvarium. 2 8 11 24 We present a case highlighting the surgical management of a frontal hemangioma with intradural extension, including a staged reconstruction aimed at optimizing postoperative cosmesis.

Clinical Presentation

An otherwise healthy 38-year-old female presented for evaluation of a large, painless mass on the forehead that slowly progressed in size over 7 months. Physical examination revealed a large, palpable, nontender mass in the frontal region. She was worked up with a noncontrasted computed tomography (CT) head demonstrating a 5.5 × 3.2 × 5.6 cm well-circumscribed mass with an internal sunburst pattern of trabecular thickening, expanding through the inner and outer tables of the right anterior frontal bone ( Fig. 1 ). A contrast-enhanced magnetic resonance imaging (MRI) of the lesion was obtained for better characterization, which demonstrated a heterogeneously enhancing lesion with T2 hyperintensity causing significant mass effect on the underlying brain parenchyma ( Fig. 2 ).

Fig. 1

Noncontrasted computed tomography (CT) preoperative coronal ( A ) and sagittal ( B ) images displaying well-circumscribed mass with trabecular thickening.

Fig. 2

Preoperative T1-weighted postcontrast magnetic resonance imaging demonstrating large heterogeneously enhancing extra-axial lesion with mass effect on the underlying brain parenchyma. Representative coronal ( A ) and sagittal images ( B ).

While the lesion was favored to represent an intraosseous hemangioma, metastasis remained on the differential. A CT of the chest, abdomen, and pelvis was obtained. The chest CT revealed a 2.4 × 3.3 cm right lateral breast mass most consistent with a hamartoma on follow-up mammogram. Given the size of the frontal lesion and associated mass effect on the underlying brain parenchyma, surgical resection of the lesion was recommended. She underwent evaluation for preoperative embolization to assist with resection of the lesion. During the diagnostic cerebral arteriogram, the anterior falcine artery was found to be the lesion's major blood supply and was secondarily supplied by a branch of the right superior temporal artery (STA). The anterior falcine artery had an anastomosis with the right ophthalmic artery, therefore endovascular embolization was not further pursued given the risk of postprocedural blindness.

The patient was taken to the operating room for surgical intervention. A bicoronal incision was made ( Fig. 3 ), and the branch of the STA found angiographically to be supplying the lesion was cauterized. After adequate exposure was obtained, a 5-mm diamond burr was used to create a full-thickness trough around the lesion. The tumor was then elevated and noted to be extending intradurally with adherence to the underlying brain parenchyma ( Fig. 4 ). The bulk of the tumor was removed to better visualize the intradural component, as it was deemed unsafe to remove the mass in an en bloc fashion ( Fig. 5 ). The remainder of the tumor was gently dissected from the underlying cortex and removed in a piecemeal fashion. A dural patch was sewn in and a temporary titanium mesh cranioplasty was placed. The final pathologic diagnosis confirmed intraosseous hemangioma.

Fig. 3

Intraoperative exposure of large frontal bone lesion utilizing a bicoronal incision.

Fig. 4

Intraoperative elevation of frontal bone lesion revealing intradural extension of tumor and adherence to underlying brain parenchyma.

Fig. 5

Intraoperative photos display resected bulk of frontal bone tumor ( A ) and the resection cavity with the exposed underlying brain parenchyma ( B ).

Postoperatively, a thin-cut CT was obtained to design a custom polymethyl methacrylate implant. The patient returned to the operating room 3 weeks later for removal of the titanium mesh and placement of the permanent implant ( Fig. 6 ).

Fig. 6

Postoperative computed tomography (CT) coronal ( A ) and sagittal ( B ) images after placement of permanent implant 3 weeks after the initial resection.

Discussion

Intraosseous cavernous hemangiomas are benign vascular tumors. They present as firm, solitary masses that slowly progress over months or years. 1 2 4 6 7 8 9 10 11 13 15 16 19 20 25 28 33 34 Intracranial extension of a calvarial based intraosseous hemangioma is an infrequent occurrence. 1 2 3 5 13 14 19 20 Few prior reports have noted expansion of these lesions beyond the dural plane. 2 8 11 13 24 Park et al and Khanam et al describe patients with intracranial expansion loosely attached to the dura, while Peterson et al describe a patient with extension through the dura and anastomoses with the thin-walled vessels on the surface of the cerebellum. 8 11 13 Further, Nasi et al describe a case with complete erosion of the dural plane and invasion of the subdural space. 2 Similar to our patient, these cases consisted of a progressive mass with dural involvement and mass effect. To our knowledge, no specific factors have been identified that correlate with internal expansion of these lesions.

The treatment of choice is en bloc resection with 5 to 10 mm wide bone margin for the primary goals of limiting painful progression, improving cosmesis, and avoiding potential complications such as hemorrhage. 1 2 4 5 7 8 9 11 12 13 14 17 19 20 25 34 35 Utilization of preoperative embolization can be considered to aid surgical resection by decreasing intraoperative blood loss. 7 10 20 25

Following surgical resection, the remaining cranial defect must be reconstructed which is particularly challenging with large lesions and those involving the forehead. We propose a staged approach as an option to optimize postoperative cosmesis, particularly for lesions involving the forehead. Several preoperative and technical nuances were helpful in this case. The first is preoperative angiography, which while unable to embolize the main anterior cerebral artery feeder, identified the branch of the STA that supplied substantial blood flow to the lesion. Given that the authors typically spare the STA if at all possible, this led to a more efficient surgical case when it was sacrificed during lesion exposure. Second, the use of a diamond drill bit to decrease intraoperative blood loss. Given the intrinsically hemorrhagic nature of these lesions, use of a diamond bur provided hemostatic capacity while allowing for debulking of the lesion.

Conclusion

The patient did very well postoperatively with a good cosmetic and neurologic outcome. An MRI obtained at 6 months postoperatively demonstrated no evidence of tumor recurrence. While rare, intraosseous cavernous hemangiomas can involve the inner table and have intradural expansion making an en bloc resection a more challenging surgical treatment strategy. In these cases, removal in a piecemeal fashion should be considered to minimize the risk of injury to the underlying brain parenchyma and vascular structures. Proper reconstruction is critical for achieving a good cosmetic outcome, and a staged reconstruction with a custom-made implant can be considered for large lesions and those involving the forehead.