Ocular adnexal intramuscular hemangioma arising from the eyelid: case report and literature review

ABSTRACT Intramuscular hemangioma (IMH) is rare in the ocular adnexa and is uncommonly found in infants. We describe a 1-month-old female infant with an unremarkable birth history presented with subacute onset of right upper eyelid swelling. Clinical examination revealed a purplish subcutaneous mass over the right upper eyelid causing mechanical ptosis. MRI revealed a well-defined subcutaneous mass, which was hyperintense on the T1 weighted images and showed intense enhancement after administration of intravenous gadolinium. Our working diagnosis was infantile capillary hemangioma, and the patient received two intralesional steroid injections without diminishing the lesion size. The lesion had become static in size and the subsequent MRI 14 years later revealed the same lesion had become hyperintense on the T1 weighted image. An excisional biopsy revealed mixed type IMH. IMH should be considered among young patients with upper eyelid swelling, particularly in those who show a poor response to steroid treatment.


Introduction
Intramuscular hemangioma (IMH) is an uncommon benign vascular hamartoma that accounts for less than 1% of all hemangioma tumours. 1 More than 90% of IMH patients were detected before the fourth decade, and it is believed that IMH is a congenital hamartomatous lesion that remains undetected for a long time until sudden growth causes symptoms. 2 IMH is frequently found to arise from the skeletal muscle of the trunk and extremities, and it is uncommon in the ocular adnexa. 2 IMH arising from the eyelid is rare; to the best of our knowledge, only four cases have been previously reported. [3][4][5][6] We report a rare case of infantile eyelid IMH mimicking infantile capillary haemangioma with significant changes of the magnetic resonance image (MRI) features over time.

Case report
A healthy 1-month-old female infant was brought to our clinic for right upper eyelid swelling over 1 week. She was a healthy term infant, and her parents denied a history of insect bite/trauma or an episode of fever. Clinical examination revealed a 20 × 15mm purplish oval-shaped mass located subcutaneously over the right upper eyebrow. There was no skin discolouration, and the lesion caused mechanical ptosis. Pulsation and bruit were not noted. The ocular motility was full, and the eyes were orthophotic and non-proptotic. Anterior segment and fundus examination were unremarkable.
Orbital MRI revealed a well-defined subcutaneous lesion in the right supraorbital region measuring 15 (TS)x21(AP)x21(CC) mm in size. The lesion was hypointense on T1-weighted images ( Figure 1a) and hyperintense on T2-weighted images with respect to the extraocular muscles, and it was intensively enhanced after administration of intravenous gadolinium contrast. Both the clinical and radiological features were compatible with the diagnosis of infantile capillary hemangioma, and the differential diagnosis included hematoma, lymphangioma, arteriovenous malformation, port-wine stain, periorbital cellulitis, acute dacryoadenitis, rhabdomyosarcoma and lymphoma.
The right upper eyelid swelling persisted, and cycloplegic refraction revealed severe astigmatism of the right eye (Sphere: +4.50D, Cylinder: −4.00D, Axis: 12 degree). Given the high risk of meridional amblyopia, the patient received the first intralesional steroid (2 mg mixture of dexamethasone (40 mg/ml) and triamcinolone (4 mg/ ml)) injection at 4 months old, followed by the second injection with the same drug formulation at 9 months old. The lesion size remained the same clinically. Parents were not keen on debulking surgery due to the risk of bleeding from highly vascular tumour excision. She subsequently developed right-eye amblyopia and required occlusion therapy.

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The right upper eyelid lesion size was static, and subsequent orbital MRI at 14 years old revealed the same subcutaneous lesion increased in size to 23(TS) x13(AP) x20(CC) mm over the same location. Surprisingly, the lesion has become hyperintense on T1weight images ( Figure 1b) and isointense on T2/Short tau inversion recovery (STIR)-weight images with respect to the extraocular muscles and only vague minimal contrast enhancement after the administration of intravenous gadolinium. The difference in the MRI features suggested the partial regression of the highly vascular lesion with potential fat infiltrations. An excisional biopsy of the lesion with a transverse lid approach was performed. The brownish unencapsulated lipomatous looking lesion was identified and completely excised.
Histopathologic examination revealed an intramuscular lesion with predominantly mature adipose tissue traversed by a variable amount of vascular proliferation, which was composed of small-sized thin-walled vessels focally and clusters of cavernous type vessels (Figures 2  and 3). The histological diagnosis was consistent with the mixed type of IMH. There was no evidence of malignancy.
The postoperative period was  uncomplicated, and there was no recurrence of lesion clinically 3 years after the operation, with satisfying aesthetic results.

Discussion
IMH is a rare benign vascular tumour that accounts for less than 0.8% of haemangioma. 1 Haemangioma is the most common vascular anomalies. 7 The term "Hemangioma" has been used indiscriminately to describe different vascular anomalies such as vascular malformation, and it was incorrectly used in 71% of the publications. 8 Hemangioma is a benign neoplasm of endothelial cells, and it usually follows the predictable course with three development phases: proliferation, quiescence and involution. 9 IMH is mostly seen in the skeletal muscle of the lower extremities, especially the thigh, and only a few cases of ocular adnexal IMHs have been reported. The aetiology of IMH has been controversial, and both congenital and acquired causes such as hormonal theories have been proposed. 10 Our patient presented with right upper eyelid swelling 1 month after birth without remarkable birth history, which supports the congenital nature of IMH. Lee et al. 3 reported a case of upper eyelid IMH in a 14-year-old female, whose onset time of upper eyelid swelling was actually at 1 month of age, and the MRI showed diffuse enhancement of the lesion on T1 weighted fat suppression image which correlated with hypervascularity of the mass. In comparison to our patient, the lesion showed hyperintensity on the T1 weight image at the age of 14, which reflected the high adipose tissue composition of the lesion.
Our patient showed significant fatty overgrowth of the lesion, and the possibility of angiolipoma was considered. However, angiolipoma is often presented as multiple subcutaneous nodules of mature fat with a variable amount of capillary vessels without larger vessels histologically. 11 IMH can be classified histologically based on the vessel size of the predominant vessels, including small vessels, large vessels and mixed types. 12 Our patient was diagnosed with a mixed type of IMH involving the eyelid, and both clinical and radiological features of the initial MRI were compatible with capillary hemangioma. In comparison to infantile capillary haemangioma, which usually regresses with or without treatment, 13 our patient's upper eyelid mass persisted and responded poorly to intralesional steroid injections and required debulking surgery. Kim et al. 6 reported a case of IMH involving the Muller muscle who showed no response to oral corticosteroid and eventually required surgical debulking with no sign of recurrence 3 months after the procedure.
IMH is a rare tumour of the ocular adnexa, usually requiring histopathology for diagnosis. Our case demonstrated a change of MRI features over the years suggesting an increase of adipose tissue composition in the hyper-vascular lesion. MRI features play an important role in pre-operative planning, especially in those hyper-vascular lesions with a higher risk of intraoperative bleeding. Taking a biopsy from a highly vascular lesion is not easy, and measures must be taken to control bleeding intraoperatively. IMH is uncommonly found in the head and neck regions, and it is difficult to diagnose due to the deep location. To our knowledge, only 14 cases (Table 1) of ocular adnexal IMH have been reported in the peerreviewed literatures, including 14 females and 8 males. The average age of disease onset was 31± standard deviation: 19.3 (range: 1 month to 63-year-old) and the most common site of involvement was medial rectus muscle in 4 patients. The initial clinical presentation is variable, including 6 eyelid swellings, 2 binocular diplopias (1 with decreased vision), 2 proptoses, 2 masses, 1 eye redness and 1 pain with ocular movement.
In conclusion, ocular adnexal IMH is rare, and it gives a difficult challenge to diagnose clinically. IMH should be considered among infantile patients with eyelid lesions, which persist and respond poorly to steroid.

Disclosure statement
The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the article.

Funding
The author(s) reported there is no funding associated with the work featured in this article.