Treatment of superficial benign vascular tumors by high intensity focused ultrasound: Observations in two illustrative cases

Abstract

Background: Existing therapeutic methods for reduction or removal of superficial vascular malformations and tumors have high risks of scarring and other complications that result in aesthetic appearance less favorable than the baseline. Patients are often cautioned against intervention, which can lead to psychosocial problems and low self-esteem. Improved treatment modalities are therefore relevant from both medical and aesthetic perspectives.

Methods: Two volunteer subjects were treated with a medical 20 MHz high intensity focused ultrasound device developed for dermatological conditions. One patient was given three treatments to remove a superficial congenital hemangioma on the left middle cheek. The other patient was given a single treatment to remove seven cherry angiomas on the thighs. Handpieces with nominal focal depths of 0.8 - 1.8 mm below the skin surface were used to administer acoustic energy of 1.1 - 1.2 J/dose. An integrated dermoscope in the handpiece was used to monitor the treatment in real-time.

Results: During treatment, blood in the capillary network of the lesions was coagulated immediately, and capillary walls were collapsed due to the thermal and mechanical effects of the high intensity focused ultrasound. During the healing phase, the areas regenerated a normal skin structure with very limited scar or dyspigmentation. At follow-up, a clear aesthetic improvement was observed over the baseline for all treated targets with the exception of two cherry angiomas, where focal depth and/or dose coverage had not been optimal.

Conclusion: High intensity focused ultrasound is concluded to be a safe and efficient skin treatment for benign superficial vascular malformations and tumors.

Keywords: HIFU; cherry angioma; congenital hemangioma; dermatology; focused ultrasound; vascular tumor.

FIGURE 1

TOOsonix System ONE‐M. 20 MHz HIFU is transmitted to target lesions in the epidermis and dermis of the skin. The system has an integrated high‐resolution color dermoscope that allows real‐time control of the treatment

FIGURE 2

Congenital hemangioma on right cheek. (A): Photograph showing location of two closely spaced lesions. (B): Dermoscope picture of section in upper lesion showing a very fine capillary network connecting evenly distributed and round junctions of slightly larger capillary widening

FIGURE 3

Upper (A) and lower (B) region of congenital hemangioma directly after HIFU Treatment. The two treatment sessions are 2 weeks apart. Whitening and edema can be observed at the location of each HIFU dose. An urticarial “wheal and flare” response in the general surrounding area can be observed

FIGURE 4

Congenital hemangioma 15 weeks after first HIFU treatment. (A): Photograph showing treated area with decreased visual redness of area and generally good aesthetic result. (B): Dermoscope picture of section in upper lesion showing strongly decreased capillary network and hardly visible round junctions in the primary treatment area

FIGURE 5

Distribution of seven cherry angiomas selected for treatment by HIFU

FIGURE 6

Example of dermoscope pictures from successful removal of Cherry Angioma Number 4. (A): Before HIFU treatment. (B): Immediately after HIFU treatment. (C): 6 months after HIFU. (D): 12 months after HIFU treatment. A full removal without fibrotic tissue, remanent capillary network, or de‐pigmentation can be observed

FIGURE 7

Example of dermoscope pictures from successful removal of Cherry Angioma Number 1. (A): Before HIFU treatment. (B): Immediately after HIFU treatment. (C): 6 months after HIFU treatment. (D): 12 months after treatment. A full removal of the angioma with minimal fibrotic change and no remanent capillary network or de‐pigmentation can be observed

FIGURE 8

Example of dermoscope pictures from partially successful removal of Cherry Angioma Number 5. (A): Before HIFU treatment. (B): Immediately after HIFU treatment. (C): 6 weeks after HIFU treatment. (D): 12 months after HIFU treatment. A full removal with, but with some fibrotic change and de‐pigmentation can be observed

FIGURE 9

Example of dermoscope pictures from unsuccessful removal of Cherry Angioma Number 2. (A): Before HIFU treatment. (B): 6 months after HIFU treatment. (C): 12 month after HIFU treatment. A partial reduction of the angioma can be observed, but parts of the original angioma has regenerated a capillary network and is supplied with fresh blood. The capillaries can be observed to be relatively deep and course, and the original HIFU treatment has thus not been sufficiently deep and densely administered

FIGURE 10

Example of dermoscope pictures from unsuccessful removal of Cherry Angioma Number 6. (A): Before HIFU treatment. (B): 6 months after HIFU treatment. (C): 12 months after HIFU treatment. A reduction in the size and capillary network can be observed, but the angioma has regenerated most capillary network and the soft tissue and is supplied with fresh blood

FIGURE 11

Macroscopic photographs. (A): Before HIFU treatment. (B): 12 months after HIFU treatment. Five of the seven cherry angiomas are not clinically visible. Two cherry angiomas (number 2 and 6) have been reduced in sized but are still clearly visible and would need re‐treatment to be fully removed