Although therapeutic management of
hypertrophic scars and
keloids using contact or spray
cryosurgery has yielded significant improvement or complete regression of
hypertrophic scars and
keloids, it requires one to 20 treatment sessions. This study was designed to assess the clinical safety and efficacy of an intralesional needle cryoprobe method in the treatment of
hypertrophic scars and
keloids. Ten patients, ranging in age from 3 to 54 years, with a total of 12
hypertrophic scars and
keloids of more than 6 months duration and of diverse causes, were included in this study. The 18-month trial evaluated volume reduction of the
hypertrophic scars and
keloids after a single session of intralesional
cryotherapy. Objective (hardness and color) and subjective (
pain/tenderness and itchiness/discomfort) parameters were examined on a scale of 0 to 3 (low score was better). Pretreatment and posttreatment histomorphometric studies of the
collagen fibers included spectral
picrosirius red polarization and fast Fourier transformation orientation index. A specially designed cryo-needle was inserted into the long axis of the
hypertrophic scars and
keloids so as to maximize the volume of the
hypertrophic scars and
keloids to be frozen. The cryo-needle was connected by an adaptor to a cryogun filled with liquid
nitrogen, which was introduced into the cryoprobe, thereby freezing the
hypertrophic scars and
keloids. After the
hypertrophic scars and
keloids were completely frozen, the cryoprobe defrosted and was withdrawn. An average of 51.4 percent of
scar volume reduction was achieved after one session of intralesional
cryosurgery treatment (average preoperative
hypertrophic scars and
keloids volume, 1.82 +/- 0.33; average posttreatment volume, 0.95 +/- 0.21; p < 0.0022). Significant alleviation of objective and subjective clinical symptoms was documented. Mild
pain or discomfort during and after the procedure was easily managed. Only mild local
edema and epidermolysis, followed by a short reepithelialization period, were evident. During the 18-month follow-up period, there was no evidence of
bleeding,
infection, adverse effects, recurrence, or permanent depigmentation. The histomorphometric analysis demonstrated
rejuvenation of the treated
scars (i.e., parallelization) and a more organized architecture of the
collagen fibers compared with the pretreated
scars. This study demonstrated the increased efficacy of this method as a result of increased freezing area of deep
scar material compared with that obtained with contact/spray probes. As a result, fewer treatment cycles are needed. Because the reepithelialization period is short, treatment intervals, if any, can be shortened to 2 to 3 weeks. This intralesional cryoneedle method is simple to operate and safe to use, it necessitates less
postoperative care of the
wound, and it can easily be added to any preexisting cryosurgical unit.