Cold caps to prevent hair loss after chemotherapy

Hair loss is common during chemotherapy and the resultant hair loss has a major impact on the psychological well being of cancer patients.

Several "cold caps" or scalp cooling devices are now available worldwide for use by cancer patients. These devices help to cool the scalp during chemotherapy and this, in turn, constricts blood vessels which lessens the amount of the chemotherapy drug that can reach the follicles. This may reduce the risk of hair loss during chemotherapy for many users of these devices.

Several devices are now available. On Dec 8, 2015, the US FDA approved the Dignicap - making it the first approved device in the US.

The cooling devices are generally worn 20 minutes before the chemotherapy, during the chemotherapy and after. Some patients get very cold during treatment and many patients get headaches.

These devices may help some women keep some or quite a bit of their hair during and after chemotherapy. Because the caps are so cold, they narrow the blood vessels beneath the skin of the scalp, reducing the amount of chemotherapy medicine that reaches the hair follicles. With less chemotherapy medicine in the follicles, the hair may be less likely to fall out. 
A study from the Netherlands set out to determine the optimal temperature for scalp cooling for women with breast cancer.

The files of 62 women with breast cancer who were receiving the drug anthracycline were reviewed. Scalp cooling was used during treatment. After wearing the devices, 13 of 62 women did not require a wig or hairpieces after completing their chemotherapy. The mean (average) skin temperature of women who did not lose much hair with scalp cooling was 18 C compared to 20 C in women who did lose hair. 
The conclusion of the study was that lower temperatures are likely better for women with breast cancer who use scalp cooling during treatment.

Reference

Results of scalp cooling during anthracycline containing chemotherapy depend on scalp skin temperature.
Komen MM, et al. Breast. 2016