๐ ็ธฝ็ฎ้ ๏ฝ ๐ ่ฑๆๅๆ๏ผๆฌ็ฏ๏ผ ๏ฝ ๐ ๅฎๆด็ฟป่ญฏ ๏ฝ โญ ็ฒพ่ฏ็ญ่จ
Pressure Alopecia (Pressure-Induced Alopecia)
Pressure alopecia usually develops following prolonged immobilization as occurs with a lengthy surgical procedure or hospitalization in an intensive care unit. Most commonly the patient is supine with the head fixed in one position on the operating table or bed and the pressure alopecia appears on the occiput. In theory, there is locally reduced microcirculation due to pressure. Although complete hair regrowth usually occurs, cases of permanent (i.e. cicatricial) hair loss have been reported. Nonspecific findings are seen by trichoscopy. An analogous condition in newborns is the halo scalp ring which manifests as a self-resolving occipital band of alopecia. The ring is believed to be due to pressure from the maternal cervix during labor.