Table 1

Summary of Common Problems During FUE; Graft Harvesting

	Problem	Description	Correction
Problems with insufficient punch depth	Tethering	Graft requires excessive force to be removed or may not be able to be removed at all.	Increase length of punch by small increments (0.2mm) and test a few grafts with technician with every increase until grafts can be removed easily. Manually apply more force during each excision, which can provide 0.2-0.4mm more depth.
	Capping	Scored cutaneous layer of the graft (skin cap) is removed while the follicular unit remains anchored.
	Skeletonized follicles	Graft does not contain the thin translucent layer representing the follicular root sheath.
Problems with excessive punch depth	Aspiration	Graft immediately enters the lumen of the punch after being scored.	Decrease length of the punch by small increments (0.2mm) until aspiration stops. Work with technician to ensure that change does not overcompensate and result in tethering.
Problems with incorrect approach angle	Complete transection	Entire graft is severed above the bulb.	Cause is multifactorial and can be difficult to identify. Work closely with technician and troubleshoot with different approach angles.
	Partial transection dorsal	Approach angle is too large, causing the punch to cut through the most dorsal hair shafts within the follicular unit.	Orient the punch with a more acute angle in relation to the skin.
	Partial transection ventral	Approach angle is too small, causing the punch to cut through the most ventral hair shafts within the follicular unit.	Orient the punch with a less acute angle in relation to the skin.
	Partial transection lateral	Punch is off-center or tilted away from the direction of the hair follicle, causing a premature transection of the more lateral hair shafts.	Using proper loupes that provide good stereotactic magnification to orient the punch directly at the hair follicle with zero tilt.
	Paring	Follicular sheath is cut in longitudinal fashion. Paring is a milder version of partial transection as the hair shafts remain intact.	Approach angle should be corrected based on the surface that the paring occurs (dorsal, ventral, lateral), similar to partial transections.
Multifactorial	Broken follicle	Bending or separation of a follicle due to stress at some point along the length of the follicle.	Adjust the approach angle and use flared punches to keep the cutting edge away from the follicle. Use the minimal effective punch depth that will liberate the follicle.