Selective Photodestruction of Facial Telangiectasia

with the Copper Vapor Laser

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  1. MATERIALS AND METHOD

    2.

Since 1996 we have treated telangiectasias in different areas of the body by selective photocoagulation using a copper vapor laser (CVL).4 This paper reports the results achieved in the past year. The laser employed was a copper vapor laser “Yahroma-Med” manufactured by P.N. Lebedev Physics Institute, Moscow, Russia. This model uses fully sealed plasma tubes with life-time more than 1500 hours, which can be replaced easily. It emits light of two wavelengths, 511 nm green light and 578 nm yellow light. The CVL light is delivered in very short pulses that last 20 nanoseconds. The interval between pulses is about 60 μseconds. The repetition rate is so high that the beam appears continuous to the human eye unless shuttered mechanically.

Although the interval between pulses is very short it is more than the thermal relaxation time tr of normal capillary vessels 20 μm in diameter for which tr is about 50 μsec 3. tr is defined as the time required for the central temperature of a gaussian temperature distribution with a width equal to the target diameter to decrease by 50 percent 3. Thus the temperature of the normal capillary vessels returns to its normal value during intervals between pulses and they are not damaged. The larger ectatic vessels have a far longer tr than the laser pulses and intervals between pulses. These vessels don’t cool noticeably between pulses and as a result the temperature increases.

To prevent the heating of abnormal vessels up to the coagulation temperature and to prevent injury to the surrounding tissue, a shuttered mode of laser emission is used. A physician can choose the appropriate exposure time (the time during which the shutter is opened). Emission in “Yahroma-Med” is delivered to the patient's skin through an optic fiber with a handpiece. During treatment the handpiece is in contact with the patient's skin. The laser beam spot size on the skin is 0,6 mm, but it can be changed by changing the tip. This characteristic combination of wavelength, pulse duration, exposure time and laser beam spots size results in unique opportunity to selectively damage ectatic abnormal vessels without injuring surrounding tissue.

This study involved 111 patients with telangiectasias of the face, aged from 13 to 55 years. Common locations were the nose (49 out of 111 patients) and the cheeks. Only 4 out of 111patients had the chin treated.

Telangiectasias were described as ‘small’ if the vessel size was less than 0,1 mm in diameter. “Medium” vessels are approximately 0.1 ÷ 0.3 mm, and “large” ones are greater than 0.3 mm. Vessel size was categorized visually using a 2.5x magnifying loupe.80% of the patients had linear telangiectasias. Patients younger than 17 years old usually had punctuate telangiectasias. Brief information about patients is listed in Table 1.

Table 1. Results of Selective Laser Coagulation of facial telangiectasias

 

Vascular lesions under treatment

Number of

patients

Males/females

Number of

treatment

Calculated assessment

unacceptable

fair

good

excellent

1

Arborizing large telangiectasia

1/4

3-4

-

-

1

4

2

Large telangiectasia of cheek-bones skin

2/5

2-3

-

1

6

-

3

Small telangiectasia of cheek-bones skin

0/15

2

-

-

2

13

4

Telangiectasia of nasal alae

0/25

3-5

3

-

10

12

5

Telangiectasia of nasal tip and alae

2/10

2-4

-

-

2

10

6

Telangiectasia of cheeks

0/5

2

-

-

-

5

7

Telangiectasia of top of a nose

2/7

2

-

-

-

9

8

Telangiectasia of chin

1/3

2

-

 -

-

4

9

Star telangiectasia

0/25

2-3

-

 -

5

20

10

Angioma

0/4

2

-

 -

-

4

Total

(%)

-

111

(100%)

-

3

(3%)

1

(1%)

26

(23%)

81

(73%)

Patients were told to avoid excessive sun exposure, and not to use aspirin and aspirin containing products such as ibuprofen, nonsteroidal anti-inflammatory agents and Vitamin E for two weeks prior to treatment. Patients with clotting problems or taking anti-coagulants were excluded from our investigation.

Each laser exposure produced a brief stinging sensation. Although uncomfortable, all patients tolerated this well and anesthesia wasn't required. To minimize this uncomfortable sensation during treatment and the effect of erythema after treatment, ice was applied before and after treatment to cool the skin. Both patients and operators used protective eye equipment during the treatment.

The treatment parameters were chosen based on the size and color of the lesions, the patient's skin type and the surgeon's experience. The laser power was measured at the handpiece output and during treatment, it varied from 0.8 to 1.3 Watts. The exposure time necessary to achieve disappearance of abnormal vessels without damage to the surrounding tissue ranged from 0.1 to 0.2 seconds (Fig.2). Most spots were 0.6 mm in diameter. When treating vessels, it is desirable to leave some untreated area between treated spots. A 1 mm spot was left between treated areas for small vessels and 0.5 mm was used for larger vessels. When larger vessels were treated sometimes two exposures were needed to treat one area.

“Spider” telangiectasia on the legs was also treated. For children, the laser power was reduced by 0.2 ÷ 0.3 Watts as compared to that used to treat adults. The clinical endpoints were vessel disappearance or a persistent purple vascular discoloration indicating intravascular thrombosis.

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