Ischemia Time
Ischemia time in hair transplantation refers to how long grafts remain without blood supply. Prolonged ischemia increases cellular stress and reduces survival, while efficient handling, cooling, and timely implantation help preserve graft viability and long-term growth outcomes.
The clock starts at extraction and does not stop at placement. Ischemia time is the interval during which a graft has no blood supply of its own. Putting it into a recipient site does not end that state immediately — the graft is nourished by diffusion first, and only later by vessels growing into it. Time out of the body is therefore the beginning of the deficit, not the whole of it.
It is an organisational variable, not a chemical one. No holding solution creates blood supply. What actually shortens ischemia is the way the day is sequenced: extracting in batches and placing each batch while the next is being taken, rather than emptying the donor first and starting placement hours later. Team size and rhythm decide this; the fluid in the dish does not.
Bigger sessions lengthen it by arithmetic. The grafts taken first wait the longest, so raising the number in a single day raises the average time every graft spends without circulation. That cost is invisible on the day and is never reflected in a graft count, which is one reason the largest session available is rarely the best one on offer.
What it damages is capacity, not appearance. A graft weakened by prolonged ischemia still looks normal when it is placed. It shows up months later as thin or patchy growth in an area where everything else about the plan was correct.
Related terms
For how graft numbers are decided in the first place, see how many grafts you need. For the surgical sequence itself, see the FUE technique.
