A randomized clinical trial on the comparison between hair shaving and snipping prior to laser hair removal sessions in women suffering from hirsutism

Handheld dermatoscope versus digital camera for hair counts in laser facial hair removal

The lack of uniform and objective techniques to evaluate treatment efficacy in photo-epilation studies leads to contradictory results. Thus, there is an urgent need to explore commonly accepted assessment tools. One of the most common methods uses hair counts via digital photography. However, macrophotography may not be able to depict the vellus-like hair induced by photo-epilation. On the other hand, handheld dermatoscopy is practical, affordable and offers high-quality magnification. Hair counts from a handheld dermatoscope and a digital camera were compared in 73 women who underwent 6 sessions with the Alexandrite 755 nm laser. Significantly more hairs were counted using the dermatoscope than using the digital camera (76.9 ± 41.3 vs. 58.6 ± 31.4, p < .005), independently of hair thickness and hair density. The difference in hair counts between the two instruments was inversely related to hair thickness and directly related to hair density. The handheld dermatoscope may be a more effective tool than the widely used digital camera in evaluating the response to laser hair removal treatment.

Prevalence of telogen effluvium hair loss in COVID-19 patients and its relationship with disease severity

COVID-19 is a concerning global pandemic. Common manifestations are fever and respiratory symptoms. In addition, recent studies reported dermatological manifestations as extrapulmonary signs. One of these is telogen effluvium which is related to post COVID-19 comorbidities. The aim of this study was to assess the prevalence of telogen effluvium among COVID-19 patients. This observational cross-sectional study included 198 patients who were admitted for COVID-19. The PCR test was performed to detect positive cases. After discharge, all patients were interviewed about hair loss. Of these patients, 79 were male (39.9%), and 119 were female (60.1%). The age ranged from 18 to 85 years old. 48 patients showed hair loss. Telogen effluvium (TE) is one of the consequences of the COVID-19 pandemic. COVID-19 leads to more medications and stress situations, which trigger TE.

Paradoxical Hypertrichosis Associated with Laser and Light Therapy for Hair Removal: A Systematic Review and Meta-analysis

BACKGROUND

Paradoxical hypertrichosis (PH) is an uncommon, poorly understood adverse effect associated with laser or intense pulsed light treatment for hair removal.

OBJECTIVE

The objective of this study was to conduct a systematic review and meta-analysis to determine PH prevalence and associated risk factors.

METHODS

We conducted a systematic review and meta-analysis of studies evaluating hair removal with lasers or intense pulsed light. Primary outcome was PH prevalence. Meta-regression and subgroup analysis were used to investigate associations among treatment modality, patients' characteristics, and PH.

RESULTS

Included were 9733 patients in two randomized controlled trials and 20 cohort studies (three prospective and 17 retrospective). Pooled PH prevalence was 3% (95% confidence interval 1-6; I² = 97%). Paradoxical hypertrichosis was associated with a face or neck anatomic location, and occurred in only 0.08% of non-facial/neck cases. Treatment modality and interval between treatments had no effect on the PH rate. There were insufficient data to determine the association between sex and skin type to PH. In three out of four studies, PH gradually improved with continued therapy.

CONCLUSIONS

Based primarily on cohort studies, PH occurs in 3% of patients undergoing hair removal with lasers or intense pulsed light, yet rarely outside the facial/neck areas. Treatment modality does not seem to be a contributing factor. Continuation of treatment in areas with PH may be the most appropriate treatment.