Grand Rounds

We present the case of a patient with a long-standing, slowly progressive periorbital vascular lesion of the left upper eyelid and orbit, first noted in childhood. The lesion had remained stable for decades before demonstrating gradual enlargement and associated cosmetic asymmetry. Imaging revealed a well-circumscribed, non-enhancing vascular malformation without arteriovenous shunting or lymphatic components. Excisional biopsy was performed to establish a definitive diagnosis and to exclude malignant transformation, given the patient’s advanced age and duration of the lesion. Histopathologic examination demonstrated thin-walled, dilated capillary channels within the dermis and subcutis, lined by flattened endothelial cells without cytologic atypia or mitotic activity. Immunohistochemistry was negative for GLUT-1, excluding an infantile hemangioma, and lacked features of venous or arteriovenous malformations. The findings were consistent with a benign capillary malformation (port-wine stain type). Special stains and Ki-67 proliferation index confirmed a low mitotic rate, excluding angiosarcoma. Surgical management involved a combined case of lesional debulking with cataract surgery. Postoperatively, the patient achieved excellent functional and cosmetic results, with restoration of normal eyelid contour and preservation of ocular motility. At follow-up, visual acuity measured 20/25 OS, with no evidence of recurrence or progression. This case underscores the importance of correlating histopathologic features with vascular malformation classification (ISSVA 2018) to guide management and exclude malignant transformation in long-standing lesions. Recognition of key diagnostic markers under the microscope is essential for accurate classification and prognostication in orbital vascular anomalies.

Presentation Date: 10/23/2025
Issue Date: 03/06/2026