From Volume 38, Issue 10, December 2011 | Pages 711-713
Intramuscular haemangiomas of the head and neck region are rare. They may present as an incidental finding, a mass or swelling, pain, tenderness, limitation of movement or cosmetic deformity. Treatment depends on the clinical signs and symptoms. Because of the apparent rarity of this lesion, we report a case of an incidental finding of multiple radio-opacities in a dental panoramic tomograph that was diagnosed as cavernous haemangioma in temporalis muscle with multiple phleboliths.
Intramuscular haemangiomas (IMH) are uncommon tumours in the head and neck region, occurring most often in the trunk and extremities. Haemangiomas located in skeletal muscles represent less than 1% of all haemangiomas. Of these, less than 20% occur in the head and neck region, predominantly in the masseter and trapezius muscles. Intramuscular haemangiomas in the temporalis muscle are rare. Previously reported cases include cavernous, capillary and venous haemangiomas. Cavernous haemangiomas in the muscles of the head and neck can be clinically distinguished from the more aggressive capillary ones. Complications associated with IMH are rare, but include haemorrhage or functional deficits. In this paper, we report a case of an incidental finding of multiple radio-opacities in a dental panoramic tomography (OPG) that is diagnosed as cavernous haemangioma in temporalis muscle with multiple phleboliths.
A 57-year-old female was referred to our oral and maxillofacial surgery unit by her general dental practitioner with symptoms of pain originating from the upper right quadrant and a finding of multiple radio-opacities in a dental panoramic tomography (DPT/OPG) in and around the right maxillary tuberosity region (Figures 1 and 2).
Initial presentation was a swelling and pain in the upper right quadrant adjacent to the first molar. The UR6 was tender to percussion and had been root-filled and restored with a gold crown. Peri-apical radiographs confirmed an absence of root-filling within the mesio-buccal canal system and an associated peri-apical radiolucency. Pain was related to this chronic peri-apical abscess, but not to the multiple radio-opacities, which were palpable high in the sulcus in the tuberosity region.
The OPG radiograph shows multiple opacities measuring ~8 mm in diameter. The appearance was similar to an OPG taken 14 months previously by the GDP. An apicectomy and retrograde root-filling was arranged for UR6.
A preliminary diagnosis of phleboliths within a haemangioma was made. The differential diagnosis might include calcification within lymphoid tissue. A subsequent MRI scan with gadolinium suggested the preliminary diagnosis. T1-weighted imaging with enhancement after contrast medium showed a lesion isointense to muscle, ie having the same signal strength as muscle, restricted to the temporal muscle. T2 weighting showed a hyperintense, moderately well-defined lesion on the fat-suppressed sequence. Signal voids within the lesion suggested phleboliths. The radiologist reported an abnormal mass, measuring 1.8 x 1.0 cm in the axial plane, in the medial component of the temporalis muscle at the mid point of the right posterior-lateral aspect of the maxillary antrum. The lesion did not appear to be invading the maxillary antrum or adjacent bony structures. The signal characteristics suggested an intramuscular cavernous haemangioma of the temporalis muscle with a benign morphological configuration (Figure 3). Follow-up MRIs were recommended annually to exclude an aggressive expansile lesion, either malignant or lymphangiomatous.
The patient was reviewed one year after initial presentation and reported no symptoms from the lesion. On clinical assessment, there was no abnormality detected. The patient did not consent to further radiographic investigations. She will continue to be reviewed annually.
IMHs account for less than 1% of the numerous varieties of vascular tumours of soft tissue.1 Of these, 15–20% occur in the head and neck region, predominantly in the masseter and trapezius muscles.2,3,4 Intramuscular haemangiomas are classified into several categories, including capillary haemangioma, cavernous haemangioma and venous haemangioma. Capillary haemangioma is composed of small capillary-sized vessels, whereas cavernous haemangioma consists of thin-walled and cystic blood spaces. Venous haemangioma is composed of dilated veins with walls of varying thickness within loose fatty-fibrous stromas. Tortuous vascular channels with a stagnant blood flow results in stasis and thrombosis within the vessels. Phleboliths are calcified nodules that can be regarded as a pathognomic feature of haemangioma.
It may present as an incidental finding, a mass or swelling, pain, tenderness, limitation of movement or cosmetic deformity in the temporal fossa.5,6,7 The treatment of the haemangiomas is based on location, accessibility, depth of invasion, age and cosmetic considerations. Treatment options for haemangioma of temporal muscle include observation, irradiation, injection of sclerosing agents, corticosteroid treatment, embolization and surgical excision.3,8,9,10
IMHs appear as a high signal intensity on both T1- and T2-weighted images. A high signal intensity on the T2-weighted image is characteristic, especially of cavernous haemangioma. IMH may also appear as an isointense signal on T1-weighted images. Signal voids present within the lesion may represent phleboliths, and this was confirmed using plain radiography. As it was asymptomatic and appeared similar in comparison to previous plain radiography, it was decided to monitor and follow up the patient annually with repeat MRI.
Although the lesion extends in the tissues around the anterior wall of the maxillary antrum, an apicectomy and retrograde root-filling was performed under LA without incident on the UR6.
This patient is an example of cases that can be encountered in a general dental practice. It can present with symptoms such as temporomandibular joint pain, localized tenderness and swelling, numbness along the distribution of the trigeminal nerve, and limitation of jaw movement. It must also be borne in mind when administrating a local infiltration injection to prevent haematoma formation, infection and trismus, or during extraction, which may result in severe bleeding.
Although this is a rare lesion, it can present to general dental practitioners or specialist units as a very unusual radiographic appearance, with possible associated symptoms. Any potential hazards involved in carrying out dental treatment in the region should be noted.
