Comparative study of follicular unit extraction between different ethnic
groups with 0.9 mm & 1.0 mm punches
Dr Anastasios Vekris MD, Konstantinos Giotis,
Dr Viral Desai MD DHI Medical Group
19th ISHRS ANNUAL MEETINGAnchorage, September 14-18 2011
Since the introduction of Follicular Unit Extraction in 2003, we have witnessed significant progress in
the speed of extraction& the quality of the extracted hair follicles
In the recent years, FUE techniques have gained wide acceptance around the world & they have become very popular between hair restoration
specialists as well as patients suffering from hair loss
In general, there is a rapidly spreading worldwide trend towards minimally invasive hair restoration
procedures that will provide the best possible results with the least possible discomfort & the
minimum possible damage of the donor area
One of the key points in Follicular Unit Extraction is the caliber of the cylindrical
punch used to extract the hair follicleThe punch must have the proper caliber
in order to:• Provide the best possible extraction, avoiding total or partial transection of the hair follicle• Avoid, if possible, the numerous little empty spots in the donor area that create the “moth-like” effect
The “Moth-like” effect after FUE
High partial or total transection may affect final hair growth
Smaller punch Vs bigger punch
Higher yield of extraction Vs faster
healing & less marks
Struggle for balance
There is proof that there are differences in the caliber, length & density of the hair follicles between different ethnic groups (e.g. Caucasians Vs
Asians)In daily practice, there is evidence that patients from different ethnic backgrounds respond differently during extraction in the hands of the
same surgeon, using the same technique & the same tools
Questions• Which is the optimal choice of punch to combine high quality extraction & less visible marks in the donor area?• Is there a punch suitable for all patients?• Do people from different ethnic backgrounds have the same response to the same instruments using the same technique?
Objectives of the study
• To compare the use of different caliber punches in the same population • To compare patients’ groups of different, distinct ethnic origin in terms of quality & actual yield of extraction using the same technique & the same caliber of punches
Selection criteria-punch caliber
• The 1.0 mm punch was selected as the most commonly used punch nowadays• The 0.9 mm punch was selected on the hypothesis that it may combine the effectiveness of the 1.0 mm punch in extraction with significantly less trauma & scarring of the donor area
1.0 mm Vs 0.9 mmS= πr²
r1=0.45 mm
r2=0.5 mm
r1r
2
Although the diameter of the 0.9mm punch is only 10% smaller than the 1.0mm, the surface that is extracted is 20% smaller than
the 1.0mm
Selection criteria-ethnic groups
• Selection of distinct ethnic groups, representative of their area, from different continents & different backgrounds• Selection of distinct ethnic groups that the doctors participating in the study have sufficient experience with• Selection of one Caucasian ethnic group, the Greeks• Selection of one Asian ethnic group, the Indians
GreeksA distinct southern european ethnic group with significant influences from the Mediterranean area, Asia Minor, the Balkans & Central Europe.A vast variety of hair types & colors, from straight blond to curly black. Hair follicles of medium length.
IndiansA large, distinct Asian population resident to the Indian subcontinent with a variety of origins & characteristics, ranging from the Dravidian people of the south to the Indo-Aryan of the north.Long, thick dark colored hair with thicker & longer hair follicles.Usually straight hair but wavy or curly hair can be found mostly in south India
Materials & Methods
• Random selection of patients, separated in two groups, Greeks & Indians• Random selection of age, grade of alopecia & condition of the donor area• Doctor selection between those that:1. Had experience of both patients’ groups2. Experience in FUE procedures between 2-7 years with more than 300 hair
restoration procedures each• Assignment of cases per doctor was random
Materials & Methods• On each patient, two equal parts, side by side, in the middle of the donor area were selected, marked & photographed•The same doctor would cut the same number of hair follicles in each marked area• The caliber of the punch used would be 1.0mm or 0.9mm & it would be given randomly to the doctor by the supervisor• The doctor would perform a test extraction before the comparative study, to establish the depth & direction of the hair follicles• After the cutting of the hair follicles, the doctor would extract the hair follicles & the assistant would count the exact number of extracted hair follicles & those that were totally transected & separate them according to the number of hairs per hair follicle (singles, doubles, etc)• The supervisor would estimate the average ratio of hair per hair follicle• The hair follicles would then be transplanted to the recipient area with implanter devises• Photos were taken after the extraction & placement in both donor & recipient area• Follow up appointments to be scheduled to estimate the healing process & hair growth (1,7,30 days after & every 2 months up to 12 months after the session)
ResultsDemographics
Group Greeks (n=18) Indians (n=16)
Age 34 37
Norwood scale
III-IV III-IV
Results-Greeks0.9 punch 1.0 punch
Attempts Grafts HairsTotal
transectionRatio hair/hair
follicle Attempts Grafts HairsTotal
transection
Ratio hair/hair follicle
50 43 85 14% 1,98 50 45 92 10% 2,04
36 33 60 8% 1,82 35 32 63 8% 1,97
55 46 107 16% 2,33 55 54 124 2% 2,3
300 249 705 17% 2,83 300 259 684 14% 2,64
100 95 213 5% 2,24 100 95 229 5% 2,41
120 108 248 10% 2,3 120 113 266 6% 2,35
110 95 215 14% 2,26 110 95 208 14% 2,19
50 45 97 10% 2,16 50 46 87 8% 1,89
160 147 292 8% 1,99 160 135 251 16% 1,86
60 55 118 8% 2,15 60 50 103 17% 2,06
60 52 118 13% 2,27 60 51 130 15% 2,55
80 68 171 15% 2,51 80 73 184 9% 2,52
250 179 439 28% 2,45 250 218 539 13% 2,47
150 134 345 11% 2,57 150 136 336 9% 2,47
100 85 247 15% 2,91 100 93 221 7% 2,38
50 49 108 2% 2,2 50 49 123 2% 2,51
220 199 415 10% 2,09 220 194 400 12% 2,06
100 88 169 12% 1,92 100 95 203 5% 2,14
Average 114 98 231 12% 2,28 114 102 236 10% 2,27
Results-Indians0.9 punch 1.0 punch
Attempts Grafts Hairs
Total transecti
on
Ratio hair/hair follicle Attempts Grafts Hairs
Total transecti
on
Ratio hair/hair follicle
65 40 59 42% 1,47 65 53 95 18% 1,8
50 40 60 20% 1,5 50 43 94 14% 2,19
50 28 50 44% 1,78 50 48 98 4% 2,04
50 40 57 20% 1,43 50 46 79 8% 1,71
50 37 74 25% 2,00 50 45 101 10% 2,24
50 32 54 35% 1,7 50 44 92 12% 2,11
50 34 60 32% 1,76 50 35 64 30% 1,85
50 40 74 20% 1,85 50 37 66 26% 1,78
50 30 50 40% 1,66 50 40 92 20% 2,3
50 36 73 28% 2,04 50 41 81 18% 1,98
50 30 53 40% 1,77 50 24 34 52% 1,42
50 29 67 42% 2,31 50 39 93 22% 2,38
50 40 83 20% 2,08 50 37 80 26% 2,16
50 31 49 38% 1,58 50 34 58 32% 1,71
52 48 113 8% 2,35 52 51 124 2% 2,43
50 37 84 26% 2,27 50 44 114 12% 2,59
Average 52 36 68 30% 1,85 52 42 87 19% 2,04
Results-Comparison
Greeks Indians0.9mm 1.0mm 0.9mm 1.0mm
Total transection rate
12% 10% 30% 19%
Ratio hairs/hair follicle
2.28 2.27 1.85 2.04
Total transection rate
0.9 mm punch
1.0 mm punch
0% 10% 20% 30% 40%
IndiansGreeks
Ratio hairs/hair follicle
0.9 mm punch
1.0 mm punch
0 0.5 1 1.5 2 2.5
IndiansGreeks
Conclusions• The use of smaller caliber punch (0.9mm) does not seem to significantly affect the total transection rate (12% Vs 10%) or the ratio of hairs/hair follicle (2.28 Vs 2.27) in Greek patients•The use of smaller caliber punch (0.9mm) seems to significantly affect both the total transection rate (30% Vs 19%) & the ratio of hair/hair follicle (1.85 Vs 2.04) in Indian patients• Despite the caliber of the punch used (0.9 or 1.0 mm), it seems that there is significantly higher total transection rate in Indians in comparison to the Greeks (19% & 30% Vs 10% & 12%) & lower ratio of hairs/hair follicle (2.04 & 1.85 Vs 2.27 & 2.28)• While the use of smaller caliber punch in Greeks seems to have no negative effect to the quality & quantity of the extraction, it seems to largely affect in a negative way the quality & quantity of extraction in Indian patients • Further studies are required to establish the benefit in hair growth by using bigger or smaller caliber punches & the quality of the healing of the donor area
The significant difference in the transection rate & the hairs/hair follicle ratio between the Indians & the Greeks may be attributed to the different properties of the hair follicles in the two groups:•Indians tend to have thicker hair follicles that may be easily transected if a smaller punch is used•The hair follicles in Indians are longer and deeper in comparison to the Caucasians. This may lead to difficulties during the extraction that may lead to increased transection, partial or totalThere must be a balance between the need to extract good quality hair follicles and the need to respect the donor area
Some practical tips•Always start with a test extraction. It will guide you to choose the proper instrument •It is quite safe to use smaller caliber punches (0.9mm) in Caucasians without compromising the quality or the quantity of extraction• In Indians, keep all your guns on the table but you’ll most probably need the big ones•Always respect each individual. There is no “magic” tool that can meet the needs of all patients•Marketing small caliber extraction may be trendy & a good advertisement for your practice but always remember: 0.5mm punches will provide excellent results in the donor area without any visible marks but, most probably, there will be no visible hair growing in the recipient area as well
THANK YOU