Hair transplant success hinges on the meticulous preparation and handling of grafts. In 2025, as FUE techniques become more refined and sessions expand into mega-procedures involving 3000+ grafts, the margin for error narrows. The viability of each graft directly affects not just hair growth, but the ultimate success of the entire surgery.
Survival rates typically range from 85% to 97%, but outcomes at the top of that range are only possible with meticulous technique. From ischemic time to bio-enhanced storage, each choice a surgical team makes determines whether a follicular unit thrives or fails.
This article synthesizes current best practices to help surgeons and technicians preserve every graft’s potential.
Dr. John P. Cole’s Graft Preparation Protocol
At ForHair Clinic, Dr. John P. Cole has developed a systematic approach to graft preparation, one built not around a single innovation but refined over decades of clinical practice.
His method combines surgical precision, custom instrumentation, and a detailed understanding of follicular anatomy to consistently achieve high graft survival and natural-looking results.
Donor Harvesting
Dr. Cole prefers a single-blade elliptical excision technique. Unlike multi-blade systems designed for speed, this approach allows for careful tracking of each follicle’s natural angle and curvature. Although more time-consuming, the method significantly reduces transection rates and enhances graft viability, especially in complex donor zones where hair angles vary.
Slivering Protocol
After the donor strip is excised, it’s slivered under a 3D stereomicroscope with 10x magnification. Each sliver is trimmed to match the width of a single follicular unit. This narrow slivering technique increases usable graft yield and minimizes trauma to surrounding tissue.
In practice, a strong slivering protocol can improve graft output by 20–30%, making it a cornerstone of efficient graft preparation.
Visualization and Lighting
Dr. Cole’s dissection system relies on a combination of overhead lighting, adjustable backlighting, and a transparent dissection surface. This setup enhances contrast and depth perception, which is critical when working with dense or fibrotic tissue.
In cases involving light or non-pigmented hair, where visual contrast is naturally low, the team adjusts lighting angles and magnification to ensure follicular structures are clearly defined and accurately dissected.
Adapting Technique for Hair Type
Dr. Cole’s team adjusts their technique based on the specific traits of the donor’s hair.
- For curly or coiled hair, the follicular path is carefully followed through the dermis and subcutaneous tissue to preserve its natural arc.
- High-density donor areas, exceeding 80 follicular units per cm², require narrower slivers and more acute dissection angles to maintain precision.
- In patients with light-colored or gray hair, specialized lighting and visualization tools are employed to minimize transection and preserve graft integrity.
Hydration Protocol
Once slivers are prepared, grafts are immediately transferred to moist sterile pads, then placed in chilled petri dishes containing Ringer’s lactate or isotonic saline. The goal is controlled hydration, moist enough to protect cell membranes, but not so saturated that handling becomes difficult or increases the risk of graft trauma.
Even short periods of desiccation can compromise membrane integrity, making moisture management critical from dissection through implantation.
Trimming and Graft Architecture
Trimming focuses on retaining the lower third of the follicular unit, including the dermal papilla and a layer of surrounding fat. Dr. Cole refers to these robust grafts as “chubby grafts,” a practical term that highlights their added volume and resilience.
While slimmer grafts may offer cosmetic neatness, they are often more vulnerable to dehydration and mechanical damage. Chubby grafts, by contrast, withstand handling better and tend to survive at higher rates.
Sorting and Placement
Once trimmed, grafts are sorted by hair count. Single-hair units are reserved for the frontal hairline to ensure natural aesthetics and fine directional control.
Two- and three-hair units, including Cole’s “T-pee” triads (first described in 1998), are used in the mid-scalp and crown to increase coverage and density.
Placement strategy is based on both cosmetic design and biological behavior, ensuring that the grafts contribute to a natural and durable result.
Integration and Yield
Dr. Cole’s system doesn’t rely on shortcuts or isolated improvements. Each phase, from harvesting to trimming, reinforces the next, creating a workflow that prioritizes consistency, tissue health, and long-term results. In high-volume sessions, where ischemia time becomes a significant limiting factor, this level of integration often defines the difference between average and exceptional outcomes.
The Science of Follicular Unit Viability
To optimize graft survival, it is essential to understand the biological stresses placed on follicular units from the moment they are excised until they are reimplanted. During this ischemic period, the follicle is deprived of oxygen and nutrients, triggering a cascade of intracellular stress responses.
Ischemia-Reperfusion Injury
Following excision, grafts undergo ischemia, which is a lack of oxygenated blood flow.
Research shows that time is critical – viability remains high for a short period, but then declines. In a controlled experiment, grafts stored in saline had ~95% survival at 5 minutes and >90% at a few hours, but plummeted to ~40% survival by 24 hours at room temperature.1
On top of that, this is followed by reperfusion upon reimplantation, which paradoxically causes oxidative stress due to sudden reoxygenation.
Reactive oxygen species (ROS) generated during reperfusion can damage follicular cells and initiate apoptosis. Mitigating this form of cellular injury requires careful control of both the ischemia window and the biochemical environment in which grafts are stored.
Dehydration and Osmotic Stress
Hair follicles are particularly susceptible to dehydration due to their small volume and exposed structure. Even short periods of air exposure can lead to cell membrane disruption and loss of cellular integrity. In practice, grafts begin deteriorating after ~15–20 minutes in a dry state.
This risk is magnified in chilled environments where osmotically imbalanced solutions can lead to cell swelling or collapse. Therefore, hydration must be continuous, and storage media must be osmotically balanced.
Mechanical Trauma
Physical damage to follicular units—particularly at the bulbar region or dermal papilla—can also have a disproportionately large impact on survival.
A 2021 study rigorously examined how minor injuries affect survival: intact grafts had ~71% take, while those with a slight bulb injury dropped to ~44%, and grafts that were accidentally fractured (severed in half) almost never grew (only ~13% survival).
Crushing, torsion, or transection of the follicle can inhibit revascularization or even render the unit nonviable. Repeated handling, poor forceps control, or excessive paring of connective tissue all contribute to this risk.
Holding-Solution Showdown
Another important area – the choice of holding solution – plays a critical role in preserving follicular unit integrity during the out-of-body interval. I compare commonly used solutions based on clinical efficacy, biochemical compatibility, and practical application.
Normal Saline (0.9% NaCl)
Saline remains a mainstay in many clinics due to its accessibility and isotonic properties. However, it offers no antioxidant protection, buffering capacity, or osmotic support. While it is suitable for short-term graft hydration (<2–3 hours),4 prolonged use may accelerate cellular degradation.
Lactated Ringer’s Solution
Lactated Ringer’s improves upon saline by better mimicking extracellular fluid composition, offering modest buffering capacity and calcium support. However, like saline, it lacks cellular protectants, antioxidants, or energy substrates.
HypoThermosol FRS
Originally developed for organ preservation, HypoThermosol FRS offers a balanced intracellular-like ionic composition, pH buffering, and free radical scavengers. Clinical studies show it significantly improves graft survival when storage exceeds 4 hours. It is especially recommended for mega-sessions and cases involving delayed implantation.
ATP-Enhanced HypoThermosol
When supplemented with liposomal ATP, HypoThermosol provides direct intracellular energy replenishment. This combination has been shown to extend follicle viability for up to five days under refrigeration, making it the gold standard for long-duration procedures or remote graft transport.
Platelet-Rich Plasma (PRP)
PRP, while less stable and patient-dependent in composition, introduces endogenous growth factors like VEGF and PDGF. Soaking grafts in PRP for 10–20 minutes may accelerate angiogenesis post-implantation, reduce telogen shedding, and improve early growth.6 However, variability in preparation protocols limits standardization.
Temperature & Time Out-of-Body
Time and temperature are the two most controllable variables that influence follicular survival during graft preparation. Their interplay determines the metabolic rate of follicular cells and the duration for which they remain viable.
Room Temperature (21 °C)
Room-temperature storage maintains grafts at a physiologically neutral state, reducing the risk of cold-induced stress. However, metabolic processes continue at this temperature, meaning that the safe ischemic window is relatively short. Studies suggest that viability begins to decline sharply after 4–6 hours.
Cold Storage (4 °C)
Cooling grafts can lengthen safe out-of-body time by reducing metabolic demand, but as we saw with Beehner’s 2021 patient study, excessive cooling for short periods might not confer benefit and could even reduce survival. The latest thinking is to store grafts at a moderately cool temperature (~8–15 °C) during typical surgeries, rather than at near-freezing 0–4 °C, unless circumstances require longer preservation.7
However, it must be paired with a compatible solution such as HypoThermosol to prevent cold shock and osmotic imbalance. Avoid direct contact with ice or freezing temperatures, as this can result in crystallization damage.
Best Practices:
- Maintain cold-chain consistency during graft transfer.
- Avoid rapid shifts in temperature during reimplantation.
- Store grafts in shallow trays with consistent hydration and mild agitation to prevent sedimentation.
Bio-Enhancements During Storage
Biological enhancement of grafts during storage represents a frontier in follicular preservation. While still emerging, several modalities are showing promise in both laboratory and clinical settings.
Platelet-Rich Plasma (PRP)
Autologous PRP, when used as a storage medium or pre-implantation soak, delivers concentrated growth factors that can enhance post-implant angiogenesis and reduce lag phase.
For instance, by using ATP spray and PRP, some doctors report that at 4 months post-op, patients have a visible result that previously would take 6+ months (anecdotal, but supported by the RCT data).
Dosing typically involves a 1:5 dilution in sterile saline, with a soak duration of 10–15 minutes.
ACell MatriStem® (ECM)
Derived from porcine bladder matrix, ACell provides an extracellular scaffold that may support cellular migration and tissue remodeling. While its use is more common in donor scar repair and regenerative medicine (see how we administer CRP/PRP with ACell to support hair restoration procedures), some clinics apply it to grafts in storage to stimulate post-implant healing.
Exosomes and Stem Cell-Derived Factors
Exosomes derived from mesenchymal stem cells carry RNA and growth factors that regulate inflammation, promote angiogenesis, and may accelerate tissue integration. Although not yet standardized, early reports suggest benefits in graft resilience and reduced post-op inflammation.
Handling & Sorting: Minimizing Trauma
Graft viability is profoundly impacted by how follicular units are handled during extraction, dissection, and implantation. Trauma can occur at any of these phases and often results in subclinical damage that impairs long-term growth.
Instrument Selection
Forceps should be fine-tipped, non-serrated, and designed to avoid crushing the dermal sheath or bulb. Jeweler’s forceps or reverse-action designs can minimize torsion and grip force.
If forceps are used, they should hold the graft by the epidermal end (where the hair exits the skin), not the bulb, to avoid crush injury. The surgeon should create recipient sites of appropriate size and angle to allow the gentle slide-in of the graft.
Tissue Trimming
Excessive paring of adipose or connective tissue increases the risk of desiccation and exposes the follicle to mechanical injury. Grafts should retain enough surrounding tissue to protect the bulbar region while remaining narrow enough for insertion.
Sorting Protocols
After extraction (in strip FUT surgery) or during breaks in FUE, grafts are often sorted by the number of hairs (1-hair, 2-hair, etc.) to assist with strategic placement. This sorting must be done under proper magnification and lighting so that technicians can see without prodding the graft too much.
Never let grafts sit on dry paper – sorting surfaces should be moist (e.g., a chilled Petri dish with saline). Techs use fine instruments like dilators to gently maneuver grafts.
- 1-hair FUs: Reserved for frontal hairline design.
- 2- and 3-hair FUs: Placed posteriorly to maximize density.
- Fragile or partially transected grafts: Should be excluded or carefully placed in lower-visibility areas.
Microscopic Magnification
I recommend that all dissection and sorting be performed under magnification to prevent inadvertent trauma. High-resolution digital microscopes can also be used to document graft quality pre-implantation.
Technician Training
Standardized handling protocols, regular audits, and cross-verification systems (e.g., dual technician sign-off) help maintain consistency and reduce error rates.
Our clinic has developed advanced technician training programs emphasizing atraumatic graft handling.
Post-Op Graft Energy & Patient Care
Finally, the graft preparation process continues well beyond implantation. I always emphasize that the post-op phase is critical for ensuring follicular units survive the transition to their new vascular environment.
Liposomal ATP Spray
Applied topically every 30–60 minutes during the first 24 hours post-op, ATP spray helps support cellular energy metabolism and may reduce oxidative injury during revascularization.
Chilled Saline Rinses
Maintaining moisture in the recipient area prevents crusting and maintains an optimal microenvironment for follicular integration. Patients should be instructed to mist the area regularly and avoid mechanical trauma (e.g., rubbing, scratching).
Supportive Medications
- Minoxidil (topical): Can be resumed 10–14 days post-op to promote vascularization and stimulate anagen transition.
- Finasteride (oral): Helps stabilize native hair and support graft longevity.
- Anti-inflammatory agents: Reduce post-op edema and pressure on newly implanted grafts.
Patient Education
This is a crucial part of the equation. Patients must understand that grafts are vulnerable for the first 7–10 days. Avoiding heat, pressure, and desiccation is vital. As I found in my practice, detailed written instructions and video tutorials can enhance compliance.
Follow-Up
Regular follow-up at 1 week, 1 month, and 3 months allows the surgical team to assess graft retention and identify early complications. Optional PRP boosters at 4 weeks and 3 months can further support graft development.
FAQs
How long can a graft stay out of the body?
Ideally, under 4 hours. Beyond 6 hours, graft survival rates begin to decline unless stored in a bio-protective solution at 4 °C.
Does cold hurt the grafts during storage?
Not if properly buffered. Cold storage with HypoThermosol at 4–8 °C prolongs viability. Make sure to avoid direct contact with ice or freezing.
What’s the best solution for graft storage?
I recommend HypoThermosol with ATP for procedures longer than 4 hours. For short durations, chilled saline or Ringer’s is sufficient.
Can PRP or ACell improve results?
Yes. PRP can reduce telogen shedding and improve early growth. ACell provides regenerative scaffolding but is less commonly used.
How can patients improve graft survival post-op?
Follow hydration protocols, avoid trauma, use ATP sprays, and comply with medical therapies. Always consider the human factor. Patient behavior significantly affects graft outcomes.
Schedule a Free Consultation with ForHair
If you’re considering a hair transplant and want the highest standard of care, we invite you to schedule a free consultation with our team. At ForHair, every step of the graft preparation process is guided by evidence-based protocols, surgical precision, and a commitment to maximizing follicular survival.
Learn more about how our advanced techniques—such as ATP-enhanced storage, PRP integration, and trauma-minimized handling—can contribute to your optimal outcome.
Your hair deserves expertise.
Let’s plan it right—starting with your free consultation.
References:
- Kim JC, Hwang SJ, Lee JJ, Oh BM, Lee SJ, Kim DW, Kim JC, Kim MK. The Effects of Dehydration, Preservation Temperature and Time on the Hair Grafts. Ann Dermatol. 2002 Jul;14(3):149-152. https://doi.org/10.5021/ad.2002.14.3.149, Accessed 26 June 2025.
- Parsley WM, Perez-Meza D. Review of factors affecting the growth and survival of follicular grafts. J Cutan Aesthet Surg. 2010 May;3(2):69-75. doi: 10.4103/0974-2077.69014. PMID: 21031063; PMCID: PMC2956960., Accessed 26 June 2025.
- Kwack MH, Kim MK, You SH, Kim N, Park JH. Comparative Graft Survival Study of Follicular Unit Excision Grafts With or Without Minor Injury. Dermatol Surg. 2021 May 1;47(5):e191-e194. doi: 10.1097/DSS.0000000000002878. PMID: 33165067. Accessed 26 June 2025.
- Kim, Jungchul & Hwang, Sung & Lee, Jung & Oh, Byung & Lee, Seok & Kim, Do & Kim, Moon. (2002). The Effects of Dehydration, Preservation Temperature and Time on the Hair Grafts. Annals of Dermatology. 14. 149. 10.5021/ad.2002.14.3.149. Accessed 26 June 2025.
- Cole, John P., and William M. Reed. “The Optimal Holding Solution and Temperature for Hair Follicle Grafts.” International Society of Hair Restoration Surgery, vol. 22, no. 1, Jan. 2012, pp. 17–21, https://doi.org/10.33589/22.1.0017. Accessed 26 June 2025.
- Pathania, Vikas & Sood, Aradhana & Beniwal, Nagendra & Baveja, Sukriti & Shankar, Prerna & Patrikar, Seema. (2021). Randomized control trial to study the efficacy and safety of platelet-rich plasma as intraoperative holding solution in hair restoration surgery: A pilot study. Medical Journal Armed Forces India. 79. 10.1016/j.mjafi.2021.04.015. Accessed 26 June 2025.
- Beehner, Michael L. “A Study Comparing Survival of Hair Follicles Stored Cold and at Room Temperature.” Hair Transplant Forum International, vol. 31, no. 5, 1 Sept. 2021, pp. 165–173, www.ishrs-htforum.org/content/31/5/165.full, https://doi.org/10.33589/31.5.165. Accessed 26 June 2025.
- Qin X, He J, Wang X, Wang J, Yang R, Chen X. The functions and clinical application potential of exosomes derived from mesenchymal stem cells on wound repair: a review of recent research advances. Front Immunol. 2023 Aug 25;14:1256687. doi: 10.3389/fimmu.2023.1256687. PMID: 37691943; PMCID: PMC10486026. Accessed 26 June 2025.
