Quantification of hair follicle parameters using computer image analysis: A comparison of androgenetic alopecia with normal scalp biopsies

Computer image analysis enables large numbers of hairs to be measured in an automated fashion. In this study, we examined horizontal scalp biopsies from 10 patients with a histological diagnosis of androgenetic alopecia and 10 normal control subjects. The density of hair follicles and the ratio of terminal to vellus hairs were determined. Hair shaft, hair canal and hair follicle diameter, inner root sheath width and outer root sheath area were measured using the Chromatic Colour Image Analysis program. This study showed a statistically significant progressive decrease in size of hair canal diameters from normal terminal hairs (85.93 ± 10.07 μm) through to androgenetic alopecia terminal (68.83 ± 13.60 μm) and vellus hairs (28.67 ± 5.60 μm). This pattern is also seen with hair follicle diameters; normal terminal (268.41 ± 24.88 μm), androgenetic alopecia terminal (236.34 ± 17.23 μm), and vellus hairs (130.88 ± 19.96 μm). Outer root sheath areas, hair shaft diameters and ratio of terminal to vellus hairs were significantly larger in normal (18500 ± 4222 μm²; 82.71 ± 13.79 μm; 36:1; respectively) compared with androgenetic alopecia scalp biopsies (8403 ± 3322 μm²; 61.11 ± 14.42 μm; 3:1; respectively), whereas inner root sheath width and density did not vary significantly. Computer image analysis can be adapted for use in clinical trials where large numbers and objectivity are critical in determining the efficacy of hair growth promoters.     

Hair density, hair diameter and the prevalence of female pattern hair loss

BACKGROUND: Female pattern hair loss is common but estimates of its prevalence have varied widely. The relationships between the clinical diagnosis of female pattern hair loss and objective measurements of hair density and hair diameter have not previously been evaluated. OBJECTIVES: To determine the prevalence of female pattern hair loss and to relate the clinical findings to hair density and hair diameter. METHODS: We examined 377 women, aged 18--99 years, who presented to a general dermatology clinic with complaints unrelated to hair growth (the unselected sample). A second group of 47 women referred with typical female pattern hair loss was included in analyses of the relationships between hair density, hair diameter and the clinical diagnosis. Hair density was measured using a photographic method. In each subject the major and minor axis diameters were measured in a random sample of 50 hairs. RESULTS: Six per cent of women aged under 50 years were diagnosed as having female pattern hair loss, increasing to 38% in subjects aged 70 years and over. The mean +/- SEM hair density was 293 +/- 61.3 hairs cm(-2) at age 35 years, falling to 211 +/- 55.1 hairs cm(-2) at age 70 years. Hair density showed a normal distribution in the unselected sample. Most women classified as having female pattern hair loss had hair densities within the lower half of the normal distribution. The perception of hair loss was determined mainly by low hair density (ANOVA P < 0.001), but there was overlap in hair density between women classified as having Ludwig I hair loss and the no hair loss group, which was partly accounted for by differences in mean hair diameter (ANOVA P < 0.001). Low hair density was associated with fewer hairs of all diameters. CONCLUSIONS: Hair density in women is distributed as a normal variable, indicating that it is determined as a multifactorial trait. Women with female pattern hair loss have a hair density which falls below the mean but lies within the spectrum of the normal distribution, although other factors, including hair diameter, may affect the subjective impression of hair loss. The hair diameter data suggest that low hair density is not due to progressive diminution in hair follicle size and that follicular miniaturization may occur within the space of a single hair cycle.     

Natural progression of male pattern baldness in young men

Twenty-six men who presented with male pattern baldness (androgen-dependent alopecia), were quantitatively evaluated for scalp hair variables and compared with 13 age-matched controls. Compared to controls, significant mean differences for hair variables were found in the frontal-vertex area, while in the occipital area, a reduction in total hair density (hairs/cm2) was the only significant (P less than 0.05) finding. A large proportion (48.5%) of meaningful hair (non-vellus hair) was less than or equal to 40 mm in length, yet had diameters similar to hairs growing much longer. In controls, these hairs accounted for only 12.2% of the total population. Compared to baseline, mean values from the frontal-vertex area of subjects with androgen-dependent alopecia were significantly lower for total hair density, meaningful hair density (non-vellus hairs/cm2) and percentage of hair in the anagen growth phase, 12 and 24 months later. During this time, total hair density decreased by 6.5% after 12 months and by 11.9% after 24 months. Similarly, meaningful hair density declined at 12 months by 10.8% and by 22.7% after 24 months. No change in any hair variable was detected in controls after 12 or 24 months. Our findings suggest that medications capable of maintaining the existing hair population should be regarded as effective treatments for this condition. Left untreated androgen-dependent alopecia progressively deteriorates. The induction of non-vellus hairs less than or equal to 40 mm in length to grow longer, would substantially improve the aesthetic profile without the need to generate new hair.     

不同年龄成人头发的变化

目的 观察不同年龄成人头发的变化,探讨反映人老化的参照指标.方法 根据入选标准和排除标准征集志愿者,并依据年龄分为4组.头顶指定区域拍照后利用图像分析软件检测头发密度以及黑发率.该区域内随机拔取10根头发,利用目镜测微尺测量发干直径和毛球直径.同时,根据毛囊形态计算不同生长时期毛囊率.结果 共有96名志愿者加入本研究,男44例,女52例,年龄30~78岁.头顶头发密度、毛干直径、毛球直径、生长期毛囊率和黑发率随着年龄的增加逐渐减小,休止期毛囊率及白发率增多,并且60岁以上组明显减小,与其他3个年龄组差异有统计学意义,各组内部分指标存在性别差异.相关分析发现,毛干直径与毛球直径呈显著正相关.结论 头发的一些变化可能作为评价人老化程度的参照指标.     

HAIR DIAMETER IN FEMALE BALDNESS

Summary.— Twenty scalp hairs were plucked from each of 131 Caucasoid women, and measurements of diameter, at 1 mm intervals, starting just above the root, were made for each hair. There was little variation in diameter along normal anagen hairs in any of the subjects. The mean anagen hair diameter in 58 women with diffuse hair thinning, of whom 44 were without detectable endocrine abnormality and 14 were clinically hypothyroid, significantly decreased with age. This appeared to be an accentuation of a normal trend, although this could not be statistically established in the control group of 73 women. At any age the mean thickness of hair in the subjects with diffuse thinning was less than in normal subjects of the same age. Normal subjects showed a symmetrical distribution of hair diameter, with a marked peak at 0.08 mm. In contrast, subjects with diffuse alopecia without detectable endocrine abnormality showed a wide spread of diameters, with 2 equal peaks at 0.04 mm and 0.06 mm The hypothyroid group showed a similar distribution, except that there was a larger proportion of hairs of the smaller diameters. The results suggest that, in the development of diffuse thinning, not all follicles behave identically, and that there may be more than one type of follicle in the human scalp.     

The ultrastructure of depigmented skin in kwashiorkor

SUMMARY.— Observations were made on the epidermis of 10 Zulu infants with kwashiorkor and 5 control infants. The thickness of the kwashiorkor Malpighian layer was less than that of the controls; since no differences were apparent between kwashiorkor and control cell volumes, it was concluded that there are changes in the kinetics of cell migration in kwashiorkor. Measurements of junction granules in the basement membrane and spinous cell desmosomes indicate that they should be classified as separate entities. The lengths of kwashiorkor desmosomes were found to be less than the lengths of control desmosomes and could be associated with the fragility of the epidermis in kwashiorkor. The thicknesses of the stratum corneum (9 nm) and its individual cells (2500 Å) in kwashiorkor were thinner than those of the controls (25 nm and 8500 Å respectively). The protein content of a kwashiorkor infant's epidermis may be one third that of a well fed infant of the same build.     

Phototrichogram analysis of Japanese female subjects with chronic diffuse hair loss

Hair growth patterns of 101 Japanese female subjects with diffuse, chronic hair loss and 58 healthy Japanese female volunteers were categorized into subgroups using noninvasive quantitative methods after determining the key parameters of hair growth. Phototrichogram was performed at 0 and 48 h after clipping hairs in the parietal region of the scalp. Shaft diameters of the excised hairs were then measured. Multiple regression analysis indicated that hair densities, hair diameters, short hair ratios, and hair growth rates, but not anagen hair ratios, were significant, in order of decreasing importance, for grading female diffuse alopecia. Using cluster analysis, hair growth patterns among subjects complaining of diffuse hair loss were divided into six abnormal groups (n=60), two borderline groups (n=21), and one normal group (n=20). The control subjects judged to be normal by macroscopic observation, actually included two subjects with borderline hair growth patterns and one abnormal subject. Most of the abnormal groups shared features of female androgenetic alopecia. Hair patterns showing a decrease in hair density but without vellus hair change, however, emerged as the most prevalent and distinct pattern of chronic diffuse hair loss among the Japanese female subjects. The phototrichogram, combined with the measurement of hair diameters, is an accurate tool for assessing hair growth patterns, especially in detecting the slight changes indicative of the early phase of diffuse alopecia.     

Usefulness of TrichoScan professional in the evaluation of hair loss in females. Report of 180 cases

Background TrichoScan Professional is a computerized program used for digital measurement of hair growth and hair loss. The aim of our study was to undertake an evaluation with TrichoScan Professional of female patients consulting at our hospitals for hair loss. The purpose of our study was to determine whether TrichoScan was able to identify differences in hair parameters that would correlate with the pattern of alopecia or according to the age of the patients evaluated. Material and methods One hundred‐eighty women that consulted consecutively for loss of hair were included. Patients were aged between 8 and 85 years (mean age 36 years). Data including age, the number of hairs, hair density per square centimetre, anagen and telogen percentage and percentage of terminal and miniaturized hair were analysed. Results Results observed with TrichoScan were as below: number of hairs (mean 154.9; range 34–316). Hair density per square centimetre (mean 239; range 52–486). Hair in anagen phase (mean 62.4%; range 9–93%). Hair in telogen phase (mean 37.4%; range 7–91%). Terminal hair (mean 95.2%; range 82–100%). Vellus hair (mean 4.7%; range 0–17%). Pearson′s correlation test was used to measure the strength of the association of age with the rest of parameters. The statistical analysis showed a significant correlation between age and both the number of hairs and the hair density per square centimetre. However, no significant correlation between age and rest of the parameters was observed. Conclusions TrichoScan Professional may help to quantify hair density and in our sample, this was the only parameter showing a significant decrease according to age in various types of alopecia affecting the females.     

'Atrophic telogen effluvium' from cytotoxic drugs and a randomized controlled trial to investigate the possible protective effect of pretreatment with a topical vitamin D analogue in humans

BACKGROUND: Hair loss from cytotoxic drugs is classically ascribed to the loss of fractured hairs (anagen effluvium). Telogen hair loss has also been described but some authors have denied any effect on the hair cycle. There are conflicting reports on a protective effect of pretreatment with a vitamin D analogue on cytotoxic drug-induced hair loss in rodents. OBJECTIVES: To investigate the process of cytotoxic hair loss and any protective effect on the hair of pretreatment with topical calcipotriol. METHODS: Breast cancer patients who were about to receive cycles of chemotherapy with cyclophosphamide 600 mg m(-2), methotrexate 40 mg m(-2) and 5-fluorouracil 600 mg m(-2) were recruited and randomized to receive calcipotriol scalp solution 50 microg mL(-1) or vehicle. The solution was applied twice daily from 4 days prior to chemotherapy and continued for 14 days in each treatment cycle. Shed, plucked and cut hairs were sampled. Absolute shed rates, the proportion of major hair types, the presence of proximal hair shaft changes, regrowth (using the new anagen hair count) and hair density were assessed. RESULTS: Ten patients receiving calcipotriol and 14 receiving vehicle completed three treatment cycles and nine from both groups completed six cycles. There was no detectable effect of calcipotriol on the proportion of patients experiencing minimal hair loss from chemotherapy, shed rates, plucked telogen and fractured hair counts, the morphology of shed and plucked hair, hair regrowth or hair density. Combining results of the treatment groups, there was a large variation in the impact of chemotherapy on hair loss, from total loss in five patients to no obvious loss in five. Excluding the latter, during chemotherapy shed telogen hairs (mean 81% of shed hairs) predominated over fractured (12%) and anagen hairs (6%) (P = 0.0002). The major pathological change was proximal hair shaft tapering, baseline mean 3% of shed hairs rising to 48% (P = 0.0005) during treatment, and there was a consequent decrease in normal telogen hairs, baseline mean 98% of all telogen hairs falling to 55% (P = 0.0005) during treatment. The pathological tapered telogen hairs had normal or small, sometimes diminutive, bulbs. Fracturing of hairs with diminutive bulbs produced typical 'exclamation mark' hairs. CONCLUSIONS: The cardinal effects of cytotoxic drugs found in this study were tapering of the proximal hair shaft and premature entry of the follicle into telogen, conflicting with the conventional view that affected hair follicles continue in anagen. There was a resulting effluvium of a mixture of tapering telogen hairs and fractured hairs. As entry into telogen is an integral part of the process, cytotoxic hair loss may be regarded as a variant of the conventional 'telogen effluvium' and we propose the term 'atrophic telogen effluvium'. There was no obvious protective effect on the hair loss of prior treatment with topical calcipotriol.     

MULTIRIATE NORMAL FREQUENCY DISTRIBUTIONS FOR THE ANALYSIS OF SCALP HAIR MEASUREMENTS

SUMMARY.— Observations were made on samples of 10 scalp hairs from each of 20 male undergraduates who were all 20 years of age. The greatest diameters of the hairs were measured proximally just above the hair root and distally 40 mm. away from the root when the hair was dry and wet.
It was found that the paired dry proximal and distal measurements could have been a random sample from a bivariate normal distribution. The dry proximal and wet proximal measurements did not fit a bivariate normal distribution until a square root transformation was made on the wet measurements.
Analysis of variance of the proximal dry measurements showed that the observations on each subject were not random samples from a homogeneous population. The mean and variance of the observations differed for each subject.
In a subsidiary experiment the diameter of the hair shaft was found to be constant for distances up to 40 mm. from the hair root.
It was concluded that measurements of hair shaft diameters can be described by a multivariate normal distribution for an uncountably infinite number of variables.     

Hair-discoloration of Japanese elite swimmers

To understand hair-discoloration in relation to swimming, we examined sixty-seven elite swimmers of the Japan National Swimming Team and fifty-four, age-matched subjects as controls. The incidence of hair discoloration (61%) in the swimmers' group was significantly higher than that in controls (0%) (p<0.0001). Interestingly, surface damage of the nail plates coexisted in the swimmers with the scalp-hair discoloration. The hairs picked from the eight swimmers and two age-matched individuals as controls were examined by electron microscope (EM) and EM X-ray microanalyzer. The swimmers' discolored, golden hair revealed complete disappearance of hair cuticle both by scanning EM (SEM) and transmission EM (TEM). The quantity of melanosomes in the cortex decreased, and their diameter was smaller than that of controls. In addition, irregularly shaped melanosomes with variable electron density and less electron-dense melanosomes with white haloes were frequently observed in the swimmers' golden hair. The X-ray elemental spectrograph by SEM revealed that the content of sulfur in all the swimmers' discoloured hair was lower than that in the normal controls and that the content of chlorine in the male swimmers' discoloured hair was higher than that in the female swimmers and the normal controls. The X-ray elemental microanalysis by TEM focused on melanosomes in the cortex of the cross section and detected elemental chlorine in all swimmers' golden hairs. It did not detect any element in the control hairs. The 14C-tyrosine uptake test of hairbulbs found no significant difference between the swimmers and the normal controls. These findings suggest that hair discoloration was mainly due to cuticle damage by friction with water. Hypochlorous acid in the swimming pool water can penetrate to the hair cortex through the cuticle. It can oxidize and degenerate melanosomes there.     

Facial and abdominal hair growth in hirsutism: A computerized evaluation

Methods of objectively assessing the growth rate of hairs in hirsute women have generally required some form of shaving and have focused on studying hairs affecting the face, which has reduced the number of patients willing or able to participate in such studies. A possible solution is to assess the terminal hairs on the lower abdomen (ie, the male escutcheon) because these two body areas are the most frequently affected with excess hair growth in hirsute patients. Nonetheless, it is unclear how the growth characteristics (density, diameter, and growth rate) of the hairs on the abdomen and face differ in these patients. We hypothesize that the growth characteristics of terminal hairs on the abdomen and face are similar and that evaluation of either area may be sufficient in assessing the hair growth rate of these patients. To objectively evaluate hair growth in the face and abdomen in hirsute patients, we developed a computer-aided image analysis system capable of measuring several growth parameters. Twenty hirsute women (12 white and 8 black), aged 31.2 +/- 6.1 years, were studied. Facial and abdominal skin areas were shaved, and 3 to 5 days later the areas were photographed through a calibrated glass plate and 5 terminal hairs were plucked from each area. The daily hair growth rate (assessed by photography and by direct measurement of the plucked hair), the density of hairs (number of hairs per surface area assessed by photography), and hair diameter (of the plucked hairs) were determined. The extent of hirsutism was also measured, albeit subjectively, by a modification of the Ferriman-Gallwey method, with each area given a score of 0 (no terminal hairs seen) to 4 (terminal hairs in a pattern similar to that of a very hirsute man). Facial, abdominal, and total Ferriman-Gallwey scores were 1.3 +/- 0.6, 1.8 +/- 0.9, and 12.5 +/- 5.4, respectively. Our results indicated that facial hairs were distributed in greater density and had a greater diameter than abdominal hairs (15.6 +/- 14.2 hairs/cm(2) vs 5.4 +/- 1.9 hairs/cm(2), and 84.5 +/- 19.5 microm and 66.2 +/- 17.5 microm, respectively, P <.005). Alternatively, the growth rates of facial and abdominal hairs were similar, whether determined photographically (0.36 +/- 0.18 mm/day vs 0.43 +/- 0.19 mm/day, respectively) or from plucked hairs (1.2 +/- +0.2 mm/d vs 1.4 + 0.4 mm/d, respectively). We conclude that although the density and diameter of facial hairs are greater than that of lower abdominal hairs, these areas have very similar growth rates. Hence evaluation of either of the body areas, using an objective method of assessing hair growth, should provide equivalent results.     

Onion juice (Allium cepa L.), a new topical treatment for alopecia areata

Alopecia areata is a patchy, non-scarring hair loss condition. Any hair-bearing surface may be involved, and different modalities of treatment have been used to induce hair regrowth. This study was designed to test the effectiveness of topical crude onion juice in the treatment of patchy alopecia areata in comparison with tap water. The patients were divided into two groups. The first group [onion juice treated] consisted of 23 patients, 16 males (69.5%) and 7 females (30.5%). Their ages ranged between 5-42 years with a mean of 22.7 years. The second group [control; tap-water-treated] consisted of 15 patients, 8 males (53.3%) and 7 females (46.6%). Their ages ranged between 3-35 years with a mean of 18.3 years. The two groups were advised to apply the treatment twice daily for two months. Re-growth of terminal coarse hairs started after two weeks of treatment with crude onion juice. At four weeks, hair re-growth was seen in 17 patients (73.9%), and, at six weeks, the hair re-growth was observed in 20 patients (86.9%) and was significantly higher among males (93.7%) compared to females (71.4%) P<0.0001. In the tap-water treated-control group, hair re-growth was apparent in only 2 patients (13%) at 8 weeks of treatment with no sex difference. The present study showed that the use of crude onion juice gave significantly higher results with regard to hair re-growth than did tap water (P<0.0001), and that it can be an effective topical therapy for patchy alopecia areata.     

Biomechanical properties of human hair with different parameters

Background/purpose: Investigations on the mechanical properties of human hair are inadequate. This research explores the break force of anagen hair by forming criteria according to the diameter of hair, gender, age, strain, use of drugs and hair dyes and how these criteria affect the mechanical resistance of hair.
Methods: The resistances of anagen hair of 120 volunteers were investigated in our biomechanics laboratory. The relationship between the value of break force of hair and hair diameter, gender, age, strain, use of drugs and hair dyes was examined. Tensile tests were applied to each hair with a 50 N load cell device.
Results: The statistical evaluation demonstrated a significant difference between the break forces of hairs with different hair diameters. The hairs with a diameter of 51 μm and above had a significantly higher break force than those of 50 μm and below ( P =0.000). An insignificant correlation was observed between break force and strain ( P =0.554, r =−0.055) whereas the correlation between diameter and strain was statistically significant ( P =0.000, r =0.361).
Conclusion: The break force of hairs did not show any significant dependency on age, presence of hair dyes, gender and usage of drugs. Yet, a statistically significant difference was observed between the break forces of hairs when compared according to their diameters and strain. More research on the mechanical properties of human hair consistent with biological properties like protein structure, α keratin fibers and microfibril–matrix composite behaviors would guide dermatologists for diagnostic symptoms.     

Progressive Decrease in Hair Diameter in Japanese with Male Pattern Baldness

Fifty-six Japanese with male pattern baldness were evaluated for changes in their hair diameters over three years. The mean hair diameter significantly decreased each year. The average decrease was 1.1 μm per year. Although the percentage of vellus hair increased by 3.6% over three years, this increase rate was lower than that found in Caucasians. To precisely examine the change in hair diameter, the mean distribution of this diameter was investigated. At the beginning of the study, clear peaks were observed at 95 μm in the twenties and 45 μm in the fifties. The number of thicker hairs decreased and the high frequency peak shifted to a thinner hair diameter over 3 years. To quantify the change in the distribution of hair diameter, the percentage of hairs of more than 60 μm was examined. There was a statistically significant 5.61% decrease in the percentage of hairs with a diameter of more than 60 μm over three years. Our findings suggest that the progression of male pattern baldness in Japanese is slower than that of Caucasians and that the percentage of hairs of more than 60 μm is a sensitive index to evaluate the progression of male pattern baldness and the effects of hair growth or hair loss preventive agents.     

Physiology of the vellus hair follicle: hair growth and sebum excretion

The growth of vellus hair and the secretion of sebum from vellus hair follicles were measured on the forehead, cheek, chest, shoulder and back of healthy men and women aged 15-30 years. Hair growth was assessed by computerized image-analysis of photographs and sebum excretion by the use of Sebutape followed by image analysis. The density of vellus hairs and the percentage of growing hairs were higher on the face than on the thorax (439 hairs/cm2 with 49% growing hairs on the forehead compared with 85 hairs/cm2 with 31.5% growing hairs on the back). The rate of growth ranged from 0.03 mm/day on the forehead to 0.13 mm/day on the back. The maximum length of vellus hair significantly decreased with age; otherwise hair growth was not affected by age or sex. Some variations in hair growth and sebum secretion were observed over a period of 3 months, but no consistent rhythms were detected. There was no obvious link between vellus hair growth and sebum excretion.     

Bubble hair – a possible explanation for its distribution

A 23-year-old white woman presented with a circumscribed area of shortened hairs along the anterior hairline. Approximately 1 month previously, the involved hairs had broken abruptly following shampooing. She used a hot air blow dryer for hair styling, but did not use electric rollers or a curling iron. Nor did she bleach, dye, or permanently wave her hair. The patient's hair styling technique involved wrapping hairs of the frontal hairline over a round brush whilst blow drying. There was no personal or family history of alopecia or scalp infections.
On physical examination, an oval-shaped area of shortened hairs (5–6 cm in length) was noted along the anterior hairline (Fig. 1). The area of involvement measured 5×4 cm and was to the left of the midline. The texture of the affected hairs was coarser than that of the unaffected hairs, and these broken hairs were somewhat crinkled in appearance. There was no erythema, scale, or discrete areas of alopecia on the scalp. By light microscopy, the broken hairs demonstrated multiple bubbles within the hair shafts (Fig. 2). Some of the bubbles led to the distension of the hair shaft. There was no evidence of trichorrhexis nodosa.     

健康儿童发育过程中头发超微结构的初步研究

目的 对不同年龄儿童头发表面和横断面的形态结构进行检测分析,从超微结构方面了解出生后小儿头发的发育成熟过程和状况。 方法 健康儿童按年龄分为婴儿期组（< 1岁）、幼儿期组（1 ~ 2岁）和学龄前期组（3 ~ 5岁）,每组各30例。在顶部、颞部和枕部三个解剖部位收集样本后,使用场发射扫描电子显微镜检测,以获得毛发表面以及横截面形态学数据,包括头发横截面短径与长径、毛发指数（头发横截面短径与长径的比值）、毛小皮厚度（于毛发横截面测得,每根毛发大约包绕5 ～ 10层毛小皮）和数目（毛干表面每单位长度100 μm内包含的毛小皮游离缘数目）以及毛小皮形态（扁平波形和不规则形）。以方差分析、t检验以及卡方检验对所获得的数据进行统计学分析。 结果 方差分析显示,在相同解剖部位,3个年龄组儿童毛发短径及长径差异有统计学意义（顶部：F = 39.67、28.32,均P ＜ 0.01;颞部：F = 13.12、11.91,均P ＜ 0.01;枕部：F = 18.41、16.43,均P ＜ 0.01）,数值随着年龄增长而增大,而毛发指数没有改变。顶部头发毛小皮厚度在3个年龄组差异有统计学意义（F = 6.15,P < 0.01）,顶、颞、枕3个部位头发的毛小皮数目在3个年龄组的差异均有统计学意义（F值分别为3.29、3.36、3.48,均P ＜ 0.05）。多重比较（LSD方法）分析表明,在婴儿期组与幼儿期组、婴儿期组与学龄前期组间,儿童毛发的短径及长径差异均有统计学意义（均P ＜ 0.001）,学龄前期组儿童顶部毛小皮厚度（0.59 ± 0.09 μm）较婴儿期组（0.49 ± 0.08 μm）增加（P = 0.003）,顶、颞、枕3个部位毛发的毛小皮数目在学龄前期组均较婴儿期组减少（均P ＜ 0.05）。在相同部位男女性别之间所测毛发短径及长径、毛发指数、毛小皮厚度和数目差异均无统计学意义。两种鳞片形态在3个年龄组间的分布差异无统计学意义。 结论 毛发直径随着儿童的生长发育而增大,毛小皮厚度存在上升趋势,而鳞片数目则具有下降的趋势。     

Effective medical treatment for common baldness in women

Endocrine profiles were established in nineteen women, aged 18–43 years, with common baldness. Reduced plasma levels were found in SHBG (68%), luteal phase progesterone (52%) indicating sub-fertility, LH (42%), oestradiol (37%) and FSH (21%), while plasma total testosterone was raised in only one patient. Three women with a history of diffuse loss of scalp hair of 2, 13 and 23 years duration and a familial history of premature balding in two, were treated with cyclical antiandrogen therapy (CAT) for 52 weeks. All showed an increase in hair density (hairs/cm²), and in the number of hairs greater than 40 um diameter/cm² (meaningful density) after 24–28 weeks. The percentage of hairs in the anagen growth phase increased during therapy. Three control patients, left untreated for 26 weeks, showed no significant improvement in hair density, meaningful density or the percentage of hair in the anagen growth phase. During CAT, each patient showed an increase in plasma SHBG and a fall in plasma testosterone levels. One patient with severe depressive symptom related to hair loss prior to therapy, returned to a normal way of life without the need for psychotropic drugs.