hair transplant

Hair transplantation is a surgical technique that removes hair follicles from one part of the body, called the 'donor site', to a bald or balding part of the body known as the 'recipient site'. The technique is primarily used to treat male pattern baldness. In this minimally invasive procedure, grafts containing hair follicles that are genetically resistant to balding (like the back of the head) are transplanted to the bald scalp. Hair transplantation can also be used to restore eyelashes, eyebrows, beard hair, chest hair, pubic hair and to fill in scars caused by accidents or surgery such as face-lifts and previous hair transplants. Hair transplantation differs from skin grafting in that grafts contain almost all of the epidermis and dermis surrounding the hair follicle, and many tiny grafts are transplanted rather than a single strip of skin.

Since hair naturally grows in groupings of 1 to 4 hairs, current techniques harvest and transplant hair "follicular units" in their natural groupings. Thus modern hair transplantation can achieve a natural appearance by mimicking original hair orientation. This hair transplant procedure is called follicular unit transplantation (FUT). Donor hair can be harvested in two different ways: strip harvesting, and follicular unit extraction (FUE).

Procedure

Pre-operative assessment and planning

At an initial consultation, the surgeon analyzes the patient's scalp, discusses their preferences and expectations, and advises them on the best approach (e.g. single vs. multiple sessions) and what results might reasonably be expected. Pre-operative folliscopy will help to know the actual existing density of hair, so that postoperative results of newly transplanted hair grafts can be accurately assessed. Some patients may benefit with preoperative topical minoxidil application and vitamins.[1]

For several days prior to surgery the patient refrains from using any medicines which might result in intraoperative bleeding and resultant poor grafting. Alcohol and smoking can contribute to poor graft survival. Post operative antibiotics are commonly prescribed to prevent wound or graft infections.[2]

Harvesting methods

Transplant operations are performed on an outpatient basis, with mild sedation (optional) and injected local anesthesia. The scalp is shampooed and then treated with an antibacterial agent prior to the donor scalp being harvested.[citation needed]

There are several different techniques for harvesting hair follicles, each with their own advantages and disadvantages. Regardless of the harvesting technique, proper extraction of the hair follicle is paramount to ensure the viability of the transplanted hair and avoid transection, the cutting of the hair shaft from the hair follicle. Hair follicles grow at a slight angle to the skin's surface, so transplanted tissue must be removed at a corresponding angle.[citation needed]

There are two main ways in which donor grafts are extracted today: strip excision harvesting, and follicular unit extraction.

Strip harvesting

Strip harvesting (also known as follicular unit transplantation or FUT) is the most common technique for removing hair and follicles from a donor site. The surgeon harvests a strip of skin from the posterior scalp, in an area of good hair growth. A single-, double-, or triple-bladed scalpel is used to remove strips of hair-bearing tissue from the donor site. Each incision is planned so that intact hair follicles are removed. The excised strip is about 1–1.5 x 15–30 cm in size. While closing the resulting wound, assistants begin to dissect individual follicular unit grafts, which are small, naturally formed groupings of hair follicles, from the strip. Working with binocular Stereo-microscopes, they carefully remove excess fibrous and fatty tissue while trying to avoid damage to the follicular cells that will be used for grafting. The latest method of closure is called 'Trichophytic closure' which results in much finer scars at the donor area.

The surgeon then uses very small micro blades or fine needles to puncture the sites for receiving the grafts, placing them in a predetermined density and pattern, and angling the wounds in a consistent fashion to promote a realistic hair pattern. The technicians generally do the final part of the procedure, inserting the individual grafts in place.

Strip harvesting will leave a thin linear scar in the donor area, which is typically covered by a patient's hair even at relatively short lengths. The recovery period is around 2 weeks and will require the stitches/staples to be removed by medical personnel or sub cuticular suturing can be done.

Follicular unit extraction (FUE)

With Follicular Unit Extraction or FUE harvesting, individual follicular units containing 1 to 4 hairs are removed under local anesthesia; this micro removal typically uses tiny punches of between 0.6mm and 1.0mm in diameter. The surgeon then uses very small micro blades or fine needles to puncture the sites for receiving the grafts, placing them in a predetermined density and pattern, and angling the wounds in a consistent fashion to promote a realistic hair pattern. The technicians generally do the final part of the procedure, inserting the individual grafts in place.

FUE takes place in a single long session or multiple small sessions. The FUE procedure is more time-consuming than strip surgery. An FUE surgery time varies according to the surgeons experience, speed in harvesting and patient characteristics. The procedure can take anywhere from a couple hours to extract 200 grafts for a scar correction to a surgery over two consecutive days for a megasession of 2,500 to 3,000 grafts.[3] With the FUE Hair Transplant procedure there are restrictions on patient candidacy.[4] Clients are selected for FUE based on a fox test,[5] though there is some debate about the usefulness of this in screening clients for FUE.

FUE can give very natural results. The advantage over strip harvesting is that FUE harvesting negates the need for large areas of scalp tissue to be harvested, so there is no linear incision on the back of the head and it doesn't leave a linear scar. Because individual follicles are removed, only small, punctate scars remain which are virtually not visible and any post-surgical pain and discomfort is minimized. As no suture removal is required, recovery from Micro Grafting FUE is less than 7 days.[6]

Disadvantages include increased surgical times and higher cost to the patient.[7] It is challenging for new surgeons because the procedure is physically demanding and the learning curve to acquire the skills necessary is lengthy and tough.[citation needed] Some surgeons note that FUE can lead to a lower ratio of successfully transplanted follicles as compared to strip harvesting.

Follicular unit transplant

Follicular unit transplantation (FUT) is the traditional hair transplant method which involves extracting a linear strip of hair bearing skin from the back or the side of the scalp. The strip is then dissected to separate individual grafts.

Robotic hair restoration

Robotic hair restoration devices utilize cameras and robotic arms to assist the surgeon with the FUE procedure. In 2009, NeoGraft became the first robotic surgical device FDA approved for hair restoration.[8] The ARTAS System was FDA approved in 2011 for use in harvesting follicular units from brown-haired and black-haired men.[9]

Types of surgery

There are a number of applications for hair transplant surgery, including:

  • Androgenetic alopecia
  • Eyebrow transplant
  • Frontal hair line lowering or reconstruction (naturally high hairlines without an existing hair loss condition)

If donor hair numbers from the back of the head are insufficient, it is possible to perform body hair transplantation (BHT) on appropriate candidates who have available donor hair on the chest, back, shoulders, torso and/or legs. Body hair transplant surgery can only be performed by the FUE harvesting method and, so, requires the skills of an experienced FUE surgeon. However, there are several factors for a potential BHT candidate to consider prior to surgery. These include understanding the natural difference in textural characteristics between body hair and scalp hair, growth rates, and having realistic expectations about the results of BHT surgery.

Post-operative care

Advances in wound care allow for semi-permeable dressing, which allow seepage of blood and tissue fluid, to be applied and changed at least daily. The vulnerable recipient area must be shielded from the sun, and shampooing is started two days after the surgery. Some surgeons will have the patient shampoo the day after surgery. Shampooing is important to prevent scabs from forming around the hair shaft. Scabs adhere to the hair shaft and increase the risk of losing newly transplanted hair follicles during the first 7 to 10 days post-op.

During the first ten days, some of the transplanted hairs, inevitably traumatized by their relocation, may fall out. This is referred to as "shock loss". After two to three months new hair will begin to grow from the moved follicles. The patient's hair will grow normally, and continue to thicken through the next six to nine months. Any subsequent hair loss is likely to be only from untreated areas. Some patients elect to use medications to retard such loss, while others plan a subsequent transplant procedure to deal with this eventuality.

Cost

The cost of hair transplantation depends on the individual hair loss and consequently on the number of necessary grafts. The average price per graft ranges between $1.07 USD in Turkey up to $7.00 USD in Canada. Some clinics also offer all-inclusive packages.[10][11]

Side effects

Hair thinning, known as "shock loss", is a common side effect that is usually temporary.[12] Bald patches are also common, as fifty to a hundred hairs can be lost each day. Post-operative hiccups have also been seen in around 4% of transplant patients.[13]

History

The use of both scalp flaps, in which a band of tissue with its original blood supply is shifted to the continue bald area, and free grafts dates back to the 19th century. In 1897, Menahem Hodara successfully implanted hair taken from the unaffected areas of the scalp on to the scars that were left bald by favus. Modern transplant techniques began in Japan in the 1930s,[14] where surgeons used small grafts, and even "follicular unit grafts" to replace damaged areas of eyebrows or lashes, but not to treat baldness. Their efforts did not receive worldwide attention at the time, and the traumas of World War II kept their advances isolated for another two decades.

The modern era of hair transplantation in the western world was ushered in the late 1950s, when New York dermatologist Norman Orentreich began to experiment with free donor grafts to balding areas in patients with male pattern baldness. Previously it had been thought that transplanted hair would thrive no more than the original hair at the "recipient" site. Orentreich demonstrated that such grafts were "donor dominant," as the new hairs grew and lasted just as they would have at their original home.[15]

Advancing the theory of donor dominance, Walter P. Unger, M.D. defined the parameters of the "Safe Donor Zone" from which the most permanent hair follicles could be extracted for hair transplantation.[16] As transplanted hair will only grow in its new site for as long as it would have in its original one, these parameters continue to serve as the fundamental foundation for hair follicle harvesting, whether by strip method or FUE.

For the next twenty years, surgeons worked on transplanting smaller grafts, but results were only minimally successful, with 2–4 mm "plugs" leading to a doll's head-like appearance. In the 1980s, strip excisions began to replace the plug technique, and Carlos Uebel in Brazil popularized using large numbers of small grafts, while in the United States William Rassman began using thousands of “micrografts” in a single session.[5]

In the late 1980s, B.L. Limmer introduced the use of the stereo-microscope to dissect a single donor strip into small micrografts.[17]

The follicular unit hair transplant procedure has continued to evolve, becoming more refined and minimally invasive as the size of the graft incisions have become smaller. These smaller and less invasive incisions enable surgeons to place a larger number of follicular unit grafts into a given area. With the new "gold standard" of ultra refined follicular unit hair transplantation, over 50 grafts can be placed per square centimeter, when appropriate for the patient.[18]

Surgeons have also devoted more attention to the angle and orientation of the transplanted grafts. The adoption of the “lateral slit” technique in the early 2000s, enabled hair transplant surgeons to orient 2 to 4 hair follicular unit grafts so that they splay out across the scalp's surface. This enabled the transplanted hair to lie better on the scalp and provide better coverage to the bald areas. One disadvantage however, is that lateral incisions also tend to disrupt the scalp's vascularity more than sagittals. Thus sagittal incisions transect less hairs and blood vessels assuming the cutting instruments are of the same size. One of the big advantages of sagittals is that they do a much better job of sliding in and around existing hairs to avoid follicle transection. This certainly makes a strong case for physicians who do not require shaving of the recipient area. The lateral incisions bisect existing hairs perpendicular (horizontal) like a T while sagittal incisions run parallel (vertical) alongside and in between existing hairs. The use of perpendicular (lateral/coronal) slits versus parallel (sagittal) slits, however, has been heavily debated in patient-based hair transplant communities. Many elite hair transplant surgeons typically adopt a combination of both methods based on what is best for the individual patient.

Research and future techniques

Stem cells and dermal papilla cells have been discovered in hair follicles.[19] Research on these follicular cells may lead to successes in treating baldness through hair multiplication (HM), also known as hair cloning.[20][21]

References

  1. ^ "An Update on Diagnosis and Treatment of Female Pattern Hair Loss". Medscape Logo. Retrieved 30 May 2018.
  2. ^ Singhal, Hemant. "Wound Infection Medication". medscape. Retrieved 30 May 2018.
  3. ^ "FUE Hair Transplant Procedure - International Society of Hair Restoration Surgery". ishrs.org. 2014-09-10.
  4. ^ Onda M, Igawa HH, Inoue K, Tanino R (Dec 2008). "Novel technique of follicular unit extraction hair transplantation with a powered punching device". Dermatol Surg. 34 (12): 1683–8. doi:10.1111/j.1524-4725.2008.34346.x. PMID 19018825. S2CID 21841027.
  5. ^ Jump up to:a b Rassman WR, Bernstein RM, McClellan R, Jones R, et al. (2002). "Follicular Unit Extraction: Minimally invasive surgery for hair transplantation". Dermatol Surg. 28 (8): 720–7. doi:10.1046/j.1524-4725.2002.01320.x. PMID 12174065. S2CID 33125094.
  6. ^ Dua, Aman; Dua, Kapil (2010). "Follicular Unit Extraction Hair Transplant". Journal of Cutaneous and Aesthetic Surgery. 3 (2): 76–81. doi:10.4103/0974-2077.69015 (inactive 28 February 2022). PMC 2956961. PMID 21031064.
  7. ^ Harris JA (Nov 2008). "Follicular unit extraction". Facial Plast Surg. 24 (4): 404–13. doi:10.1055/s-0028-1102904. PMID 19034817. S2CID 902688.
  8. ^ M, Rashid, Rashid; Morgan, Bicknell, Lindsay T (1 September 2012). "Follicular unit extraction hair transplant automation: Options in overcoming challenges of the latest technology in hair restoration with the goal of avoiding the line scar". Dermatology Online Journal. 18 (9): 12. doi:10.5070/D30X57S71R. PMID 23031379.
  9. ^ "Hair transplant robot gets FDA approval, men with straight brown hair rejoice". Engadget. Retrieved 2017-12-22.
  10. ^ "Hair transplant graft cost selected countries 2021". Statista. Retrieved 2021-06-17.
  11. ^ Rose, Paul T (2015-07-15). "Hair restoration surgery: challenges and solutions". Clinical, Cosmetic and Investigational Dermatology. 8: 361–370. doi:10.2147/CCID.S53980. ISSN 1178-7015. PMC 4507484. PMID 26203266.
  12. ^ "Hair Transplant Procedures: Average Cost, What to Expect, and More". WebMD. Retrieved 2019-09-13.
  13. ^ "2020 Practice Census Results" (PDF). International Society of Hair Restoration Surgery. 2020-05-01.
  14. ^ Okuda S (1939). "The study of clinical experiments of hair transplantation". Jpn J Dermatol Urol. 46: 135.
  15. ^ Orentreich, Norman (1959). "Autografts in Alopecia and Other Selected Dermatologic Conditions". Annals of the New York Academy of Sciences. 83 (3): 463–479. doi:10.1111/j.1749-6632.1960.tb40920.x. PMID 14429008. S2CID 35356631.
  16. ^ Unger WP (1994). "Delineating the 'Safe' Donor Area for Hair Transplanting". The American Journal of Cosmetic Surgery. 11 (4): 239–243. doi:10.1177/074880689401100402. S2CID 79005826.
  17. ^ Shiell, Richard C (2008). "A Review of Modern Surgical Hair Restoration Techniques". Journal of Cutaneous and Aesthetic Surgery. 1 (1): 12–16. doi:10.4103/0974-2077.41150. ISSN 0974-2077. PMC 2840892. PMID 20300332.|date=January 2008|access-date=2019-09-13}}
  18. ^ Alam, Murad. Evidence-Based Procedural Dermatology. Springer November 2011; 382-3.
  19. ^ "Functional hair follicles grown from stem cells". SBP. 2019-06-27. Retrieved 2019-09-13.
  20. ^ "Hair Cloning Nears Reality as Baldness Cure". WebMD. 2004-11-04. Retrieved 2019-09-13.
  21. ^ Lee, Jiyoon; Rabbani, Cyrus C.; Gao, Hongyu; Steinhart, Matthew R.; Woodruff, Benjamin M.; Pflum, Zachary E.; Kim, Alexander; Heller, Stefan; Liu, Yunlong; Shipchandler, Taha Z.; Koehler, Karl R. (2020-06-01). "Hair-bearing human skin generated entirely from pluripotent stem cells". Nature. 582 (7812): 399–404. Bibcode:2020Natur.582..399L. doi:10.1038/s41586-020-2352-3. ISSN 1476-4687. PMC 7593871. PMID 32494013.

Further reading

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Philadelphia

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colonies

In politics and history, a colony is a territory under the immediate political control of a state, distinct from the home territory of the sovereign. For colonies in antiquity, city-states would often found their own colonies. Some colonies were historically countries, while others were territories without definite statehood from their inception. The metropolitan state is the state that owns the colony. In Ancient Greece, the city that founded a colony was called the metropolis. “Mother country” is a reference to the metropolitan state from the point of view of citizens who live in its colony. There is a United Nations list of Non-Self-Governing Territories. Unlike a puppet state or satellite state, a colony has no independent international representation, and its top-level administration is under direct control of the metropolitan state. The term informal colony is used by some historians to refer to a country under the de facto control of another state, although this term is often contentious.

North Carolina

North Carolina () is a state in the Southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west, Virginia to the north, and the Atlantic Ocean to the east. North Carolina is the 28th most extensive and the 9th most populous of the 50 United States. North Carolina is known as the Tar Heel State and the Old North State. North Carolina is composed of 100 counties. North Carolina’s two largest metropolitan areas are among the top ten fastest-growing in the country: its capital, Raleigh, and its largest city, Charlotte. In the past five decades, North Carolina’s economy has undergone a transition from reliance upon tobacco, textiles, and furniture-making to a more diversified economy with engineering, energy, biotechnology, and finance sectors. North Carolina has a wide range of elevations, from sea level on the coast to at Mount Mitchell, the highest point in the Eastern US. The climate of the coastal plains is strongly influenced by the Atlantic Ocean. Most of the state falls in the humid subtropical climate zone. More than from the coast, the western, mountainous part of the state has a subtropical highland climate.

Commander-in-Chief

A commander-in-chief is the person or body that exercises supreme operational command and control of a nation’s military forces or significant elements of those forces. In the latter case, the force element is those forces within a particular region, or associated by function. As a practical term, it refers to military competencies that reside in a nation-state’s executive leadership—either a head of state, a head of government, a minister of defence, a national cabinet, or some other collegial body. Often, a given country’s commander-in-chief (if held by an official) need not be or have been a commissioned officer or even a veteran. This follows the principle of civilian control of the military. The role of commander-in-chief derives from the Latin, imperator. Imperatores of the Roman Republic and Roman Empire possessed imperium (command) powers. In its modern use, the term first applied to King Charles I of England in 1639. A nation’s head of state (monarchical or republican) usually holds the nominal position of commander-in-chief, even if effective executive power is held by a separate head of government. In a parliamentary system, the executive branch is ultimately dependent upon the will of the legislature; although the legislature does not issue orders directly to the armed forces and therefore does not control the military in any operational sense. Governors-general and colonial governors are also often appointed commander-in-chief of the military forces within their territory. A commander-in-chief is sometimes referred to as Supreme Commander, which is sometimes used as a specific term. The term is also used for military officers who hold such power and authority, not always through dictatorship, and as a subordinate (usually) to a head of state (see Generalissimo). The term is also used for officers that hold authority over individual branches or within a theatre of operations.

New Hampshire

New Hampshire () is a state in the New England region of the northeastern United States. The state was named after the southern English county of Hampshire. It is bordered by Massachusetts to the south, Vermont to the west, Maine and the Atlantic Ocean to the east, and the Canadian province of Quebec to the north. New Hampshire is the 5th smallest, and the 9th least populous of the 50 United States. In January 1776 it became the first of the British North American colonies to establish a government independent of Great Britain’s authority, although it did not declare its independence at the time. Six months later, it became one of the original 13 states that founded the United States of America, and in June 1788 it was the ninth state to ratify the United States Constitution, bringing that document into effect. New Hampshire was the first U.S. state to have its own state constitution. It is known internationally for the New Hampshire primary, the first primary in the U.S. presidential election cycle. Concord is the state capital, while Manchester is the largest city in the state. It has no general sales tax, nor is personal income (other than interest and dividends) taxed at either the state or local level. Its license plates carry the state motto: “Live Free or Die”. The state’s nickname, “The Granite State”, refers to its extensive granite formations and quarries. Among prominent individuals from New Hampshire are founding father Nicholas Gilman, Senator Daniel Webster, Revolutionary War hero John Stark, editor Horace Greeley, founder of the Christian Science religion Mary Baker Eddy, poet Robert Frost, astronaut Alan Shepard, and author Dan Brown. Additionally, actor Adam Sandler grew up, but was not born in, the state. New Hampshire has produced one president: Franklin Pierce. With some of the largest ski mountains on the East Coast, New Hampshire’s major recreational attractions include skiing, snowmobiling, and other winter sports, hiking and mountaineering, observing the fall foliage, summer cottages along many lakes and the seacoast, motor sports at the New Hampshire Motor Speedway, and Motorcycle Week, a popular motorcycle rally held in Weirs Beach near Laconia in June. The White Mountain National Forest links the Vermont and Maine portions of the Appalachian Trail, and boasts the Mount Washington Auto Road, where visitors may drive to the top of Mount Washington.

Appalachian Mountains

The Appalachian Mountains ( or , ), often called the Appalachians, are a system of mountains in eastern North America. The Appalachians first formed roughly 480 million years ago during the Ordovician Period and once reached elevations similar to those of the Alps and the Rocky Mountains before they were eroded. The Appalachian chain is a barrier to east-west travel as it forms a series of alternating ridgelines and valleys oriented in opposition to any road running east-west. Definitions vary on the precise boundaries of the Appalachians. The United States Geological Survey (USGS) defines the Appalachian Highlands physiographic division as consisting of thirteen provinces: the Atlantic Coast Uplands, Eastern Newfoundland Atlantic, Maritime Acadian Highlands, Maritime Plain, Notre Dame and Mégantic Mountains, Western Newfoundland Mountains, Piedmont, Blue Ridge, Valley and Ridge, Saint Lawrence Valley, Appalachian Plateaus, New England province, and the Adirondack provinces. A common variant definition does not include the Adirondack Mountains, which geologically belong to the Grenville Orogeny and have a different geological history from the rest of the Appalachians.

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Rocky Mountains

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