DHI (Direct Hair Implantation) uses a special pen-like tool โ the Choi implanter pen โ to place follicles directly into the scalp without pre-opening recipient channels.
Key Difference from FUE
In standard/Sapphire FUE, channels are opened in the recipient area first, then grafts are placed into them by hand. With DHI, the Choi pen both opens the micro-channel and places the graft in the same motion โ two steps become one.
Advantages
- Grafts spend less time outside the body (shorter ischemia time), which some studies associate with graft survival rates ranging 90-97%, potentially higher than standard methods.
- Allows more precise control of channel angle and depth, an advantage for natural-looking hairline design in particular.
- Can be performed without shaving the head ("no-shave DHI"), making the procedure more discreet.
Disadvantages
- Procedure time is longer, which usually means higher cost.
- Can be more logistically demanding at very high graft counts (5,000+).
- Outcomes depend heavily on the experience of the performing team.
Who it suits: Particularly favored by patients seeking a natural, dense hairline design, preferring a no-shave procedure, or needing a moderate graft count.