Surgical hair restoration allows male and female patients to achieve aesthetically natural results. The term megasession refers to transplanting greater then 3000 follicular unit grafts in a single procedure. By transplanting a large number of grafts, megasessions are capable of definitively treating a significant area of the scalp in 1 session. Patients must be carefully selected to determine whether they are appropriate candidates for an extended procedure. An experienced and well-organized surgical team is mandatory to meet the demands of this technically challenging and lengthy procedure. This article reviews the indications, contraindications, and technical perspectives surrounding megasession hair transplantation.
Key points
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Megasessions are capable of definitively treating significant areas of the scalp with 1 procedure.
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Careful patient selection and consultation are required to ensure a safe and successful outcome.
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A detailed medical history and evaluation must be obtained to determine whether a patient is an appropriate candidate for a megasession.
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Detailed preoperative planning; meticulous organization; and an experienced, efficient hair restoration team are essential for successful execution and completion of lengthy hair transplant procedures.
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Maximizing graft survival is the key component for successful implementation of a megasession.
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Organizing the grafts into small, identical unit groups; shaving the recipient area; and staining the recipient sites with methylene blue are a few techniques to maximize the efficiency of graft placement.
Introduction
The term megasession in hair restoration surgery refers to transplanting a large number of follicular unit grafts in a single session. With the abundance of literature available to the general public, patients are educated on advances in hair restoration surgery and what can be accomplished. Even though what is read may not be entirely true, patients have a better understanding of surgical hair transplantation, and, in many cases, have an expectation for a natural result with maximal coverage and minimal downtime. This result may or may not be possible depending on the patient’s expectations, medical history, current hair loss pattern, and available donor hair. It is therefore imperative for the hair restoration physician to develop a sound and ethical treatment plan for each patient. Although individuals may not be candidates for a large session, or a clinic may not have the capability to perform large sessions, it is important for the clinician to have a thorough understanding of the procedure and the technical details for a successful outcome.
Megasessions are not unique to hair restoration, and have been described in other fields of dermatologic surgery such as removing a large number of basal cell carcinomas from an individual in a single session. Although no strict definition exists, in 1995, Rassman and Carson described a megatransplant session as transplanting more then 1000 grafts in a single session. Over the years, as hair restoration has become more refined, the number of grafts transplanted per session has increased. This article refers to a megasession as transplanting greater then 3000 grafts in a single session via the strip method, although larger sessions are possible. The high numbers of grafts are now possible because surgeons are using naturally occurring follicular units and increasing the size of the donor strip.
In the past, physicians used hair plugs that may have had up to 20 to 30 terminal hairs, each containing 12 to 14 follicular units. These plugs were harvested using a 4-mm punch and were transplanted in rows producing a dolls-head appearance with islands or clumps of hair between larger-than-normal areas of skin. At most, several hundred of these plugs were transplanted per session. Although patients had a significant amount of hair transplanted, the results were not natural and, in many instances, were noticeable to others.
A major advancement in hair restoration occurred with the introduction of the binocular microscope, which allowed natural follicular units, each containing 1 to 4 hairs, to be dissected and transplanted, as first described by Limmer in 1988. By using these smaller follicular unit bundles and spreading them out more evenly in the recipient area to mimic the normal biological appearance of scalp hair, the patient was able to obtain a more natural-appearing result. As strategies evolved for larger donor tissue harvests, the numbers of follicular units transplanted increased, allowing surgeons to transplant a greater area of the scalp.
In the past, the donor strip was removed only in the occipital portion of the scalp ( Fig. 1 ). The hair in this area of the scalp is genetically resistant to the effects of dihydrotestosterone, a hormone responsible for miniaturization of hair follicles and hair loss. For the last several years, surgeons have become more aggressive, extending the harvested donor strip from the occipital portion of the scalp to the temporal/supra-auricular area of the scalp ( Fig. 2 ). In some cases, this has allowed surgeons to remove donor strips in excess of 30 cm in length, which has the potential to provide a significant amount of donor hair.
Introduction
The term megasession in hair restoration surgery refers to transplanting a large number of follicular unit grafts in a single session. With the abundance of literature available to the general public, patients are educated on advances in hair restoration surgery and what can be accomplished. Even though what is read may not be entirely true, patients have a better understanding of surgical hair transplantation, and, in many cases, have an expectation for a natural result with maximal coverage and minimal downtime. This result may or may not be possible depending on the patient’s expectations, medical history, current hair loss pattern, and available donor hair. It is therefore imperative for the hair restoration physician to develop a sound and ethical treatment plan for each patient. Although individuals may not be candidates for a large session, or a clinic may not have the capability to perform large sessions, it is important for the clinician to have a thorough understanding of the procedure and the technical details for a successful outcome.
Megasessions are not unique to hair restoration, and have been described in other fields of dermatologic surgery such as removing a large number of basal cell carcinomas from an individual in a single session. Although no strict definition exists, in 1995, Rassman and Carson described a megatransplant session as transplanting more then 1000 grafts in a single session. Over the years, as hair restoration has become more refined, the number of grafts transplanted per session has increased. This article refers to a megasession as transplanting greater then 3000 grafts in a single session via the strip method, although larger sessions are possible. The high numbers of grafts are now possible because surgeons are using naturally occurring follicular units and increasing the size of the donor strip.
In the past, physicians used hair plugs that may have had up to 20 to 30 terminal hairs, each containing 12 to 14 follicular units. These plugs were harvested using a 4-mm punch and were transplanted in rows producing a dolls-head appearance with islands or clumps of hair between larger-than-normal areas of skin. At most, several hundred of these plugs were transplanted per session. Although patients had a significant amount of hair transplanted, the results were not natural and, in many instances, were noticeable to others.
A major advancement in hair restoration occurred with the introduction of the binocular microscope, which allowed natural follicular units, each containing 1 to 4 hairs, to be dissected and transplanted, as first described by Limmer in 1988. By using these smaller follicular unit bundles and spreading them out more evenly in the recipient area to mimic the normal biological appearance of scalp hair, the patient was able to obtain a more natural-appearing result. As strategies evolved for larger donor tissue harvests, the numbers of follicular units transplanted increased, allowing surgeons to transplant a greater area of the scalp.
In the past, the donor strip was removed only in the occipital portion of the scalp ( Fig. 1 ). The hair in this area of the scalp is genetically resistant to the effects of dihydrotestosterone, a hormone responsible for miniaturization of hair follicles and hair loss. For the last several years, surgeons have become more aggressive, extending the harvested donor strip from the occipital portion of the scalp to the temporal/supra-auricular area of the scalp ( Fig. 2 ). In some cases, this has allowed surgeons to remove donor strips in excess of 30 cm in length, which has the potential to provide a significant amount of donor hair.
General principles of a megasession
There are several advantages and disadvantages of transplanting a large number of follicular units in a single session ( Table 1 ). By using a large number of grafts, either a sizable area of the scalp can be transplanted or a specific area may be covered with a high density of hair. The average density of follicular units varies significantly between races, and research by Headington has shown that it can average up to 100 follicular units/cm 2 . It is not feasibly for surgeons to transplant hair at this high of density over a significant area because it would require too much donor scalp, which generally is not available in the alopecic patient; however, it can be argued that, in any given area, more transplanted hair gives a fuller appearance and ultimately a better result.
| Advantages | Disadvantages |
|---|---|
| Treat large area in 1 session | Higher risk for patient |
| Treat a single area with higher density | Local anesthesia toxicity |
| Decreased overall downtime | Potential for decreased graft survival |
| Less scarring in recipient site | Demanding on physician, staff, and patient |
| Decreased donor site scarring | Donor site scarring with aggressive harvest |
| Decreased vascular trauma | Increased swelling |
| — | Long procedure times |
With a megasession, an individual with a Norwood IV/V pattern, who may require 4000 to 5000 grafts to achieve a satisfactory result with 30% natural density throughout the balding frontal and midscalp, can be managed in 1 procedure instead of the commonly accepted protocol that uses multiple smaller sessions of 1500 to 2000 grafts ( Fig. 3 ). The same argument holds true for a Norwood II/III patient who desires to have the frontal hairline and frontal zone treated with high-density hair in 1 session. To achieve a more desirable natural and aesthetically pleasing result, the frontal zone requires higher densities with large numbers of microscopically dissected 1-hair and 2-hair follicular units. Transplanting 3000 or more grafts to the frontal hairline region may give the patient the desired appearance of full density with only 1 procedure ( Figs. 4 and 5 ). There are also situations in which an appropriate candidate has 2 discontinuous areas of the scalp, such as the frontal zone and the crown, which with adequate donor supply can be treated using a single megasession ( Fig. 6 ). Transplantation for patients with any of these hair loss patterns can theoretically be performed with 1 session by harvesting and transplanting a higher number of grafts. However, it is important to always counsel the patient that an additional, smaller touch-up procedure may be necessary after a session of any size to achieve the final results. The advantage of the megasession, is that the bulk of the work is accomplished in 1 procedure instead of many smaller sessions.
