Influence of body water distribution on skin thickness: measurements using high-frequency ultrasound

BACKGROUND: Although it is known that the skin acts as a water reservoir and participates in the fluid content of the whole body, no method has been established to quantify the fluid shifts in superficial tissue. OBJECTIVES: The aim of this study was to investigate changes in dermal and subcutis thickness and echodensity at the forehead and lower leg by high-frequency (20 MHz) ultrasound under various physiological conditions influencing water balance. METHODS: These parameters were measured in the skin of 20 healthy male volunteers at baseline and successively at 30 min after lying down, in a head-down position, after physical activity and after infusion of 10 mL kg-1 body weight of Ringer's solution. RESULTS: Dermal thickness at the forehead showed a significant increase from baseline to a horizontal position and a further increase in the head-down position. Physical activity did not lead to further changes, whereas after fluid infusion the dermal thickness also increased markedly. The echodensity showed inverse changes, with decreasing values. The thickness of the subcutis increased slightly from baseline to a lying position and decreased in the head-down position and after fluid infusion. At the lower leg, skin thickness decreased slightly in the head-down position with elevated legs, and increased after fluid infusion. CONCLUSIONS: Our results show that slight changes in the water distribution of the body influence the thickness and the echodensity of the dermis. Changes are more pronounced at the forehead than on the lower legs. Further, the fluid storage takes place mainly in the dermis and not in the subcutis. High-frequency ultrasound is able to quantify these effects and is a sensitive method for measuring fluid intake and balance during anaesthesia and therapy.     

Hormonal Milieu in the Maintenance of Melasma in Fertile Women

Melasma is a specific type of facial hyperpigmentation seen in women taking oral contraceptives, in non-pregnant women who have not used oral contraceptives, and in some pregnant women during the progression of gestation, but rarely in men. Circulating LH, FSH, PRL, and E_2-17β on day 5, 7, 9, and 11 of the menstrual cycle and progesterone (P) on day 17, 19, and 21 were measured in thirty-six ovulating women with melasma (study group) age 25–35 years and twelve healthy controls (control group). Twenty-seven subjects in the study group had normal pregnancies; 9 others were married or single and had no history of contraceptive pill use. Higher levels of FSH on day 7 (p<0.05); E_2-17β on 5, 7, 9 (p<0.05) and LH on day 9 (p<0.002) were observed in the study group than in the control group. There were no significant differences between the LH/FSH ratio in the two groups. Serum PRL was lower on day 9 in the study group (p<0.05) than in the control group. Serum P was similar in the patients and the controls. These findings indicate a possible role of high E_2-17β in the maintenance of melasma.     

Sonography of the skin at 100 MHz enables in vivo visualization of stratum corneum and viable epidermis in palmar skin and psoriatic plaques

A main drawback of 20-25 MHz ultrasound units for skin imaging is their limited resolution. We used a transducer with a center frequency of 95 MHz and a resolution of 8.5 microm axially and 27 microm laterally - an almost 10-fold increase compared with 20 MHz. By means of a new scanning technology we reached a depth of field of 3.2 mm. We examined normal palmar skin, normal glabrous skin on the abdomen, the upper back, the calf and the dorsal forearm, and 35 lesions of psoriasis vulgaris. From 11 psoriatic plaques biopsies were taken for correlation with the sonograms. In normal palmar skin, the horny layer is represented as an echopoor band below the skin entry echo, traversed by echorich coils, which correspond to eccrine sweat gland ducts. The thickness of this band significantly increases after occlusive application of petrolatum. Its lower border is defined by an echorich line, representing the stratum corneum/stratum Malpighii-interface. Underneath, a second echopoor band is visible, which corresponds to the viable epidermis plus the papillary dermis, bordered by the scattered echo reflexes of the reticular dermis. This band is also visible in glabrous skin; however, the stratum corneum cannot be detected. In psoriatic lesions, the thickened horny layer appears echorich; after application of petrolatum, its echodensity decreases. Below, the acanthotic epidermis plus the dermis with the inflammatory infiltrate are represented as an echopoor band. There is an excellent correlation between the sonometric thickness of this band and the histometric thickness of the acanthosis plus the infiltrated dermis. Our results show that 100 MHz sonography is a valuable tool for in vivo examination of the upper skin layers.     

Comparison of nickel patch test reactivity in phases of the menstrual cycle

BACKGROUND: In earlier studies, it has been shown that severity of some diseases varies with menstrual cycle. Severity of skin diseases such as atopic dermatitis, lupus erythematosus, infections due to herpes virus, urticaria and acne were also reported to increase in the premenstrual phase. Effect of estradiol on the cellular immune system was investigated and it was found to depress the cellular immune response. In our study, we investigated whether nickel patch test reactivity was different during phases of the menstrual cycle and whether there was an increase in sensitivity to nickel during the premenstrual cycle in nickel-sensitive women. METHODS: The study consisted of 30 women who had a history of nickel sensitivity. Finn Chamber nickel patch test was applied to all 30 women by dividing them into two groups of 15 and applying the test first on days 7-10 and then on days 20-24 of the menstrual cycle or vice versa. RESULTS: The reactions of both the groups on days 20-24 were more severe than those on days 7-10 even though the results were not statistically significant. CONCLUSIONS: Estrogens not only impair the skin barrier but also have a negative impact on the immune system. Estradiol has been proved to suppress cellular immunity. In a few studies conducted to date, the relationship between phases of the menstrual cycle and the severity of patch test reactivity has been examined with equivocal results. In our study, we observed that the presence of reactions due to nickel sensitivity was independent of the phases of the menstrual cycle. Nevertheless, we would like to point out the fact that the reactions seen in the second phase of the menstrual cycle were more severe than those seen in the first phase.     

不同年龄段妇女卵巢储备功能的对比研究

目的：探讨不同年龄段妇女的卵巢储备功能的变化规律。结果：20～29岁年龄段患者的窦卵泡数量最多、卵泡体积最大,明显高于其他三组（P〈0.05）;≥40岁组卵泡数量及卵泡体积在整个月经周期里无明显变化（P〉0.05）,窦卵泡数量明显少于其他组（P〈0.05）;各年龄段血流频谱成周期性变化,且滤泡期和黄体期PI、RI、S/D值明显高于排卵期（P〈0.05）,但滤泡期与黄体期比较,无统计学差异（P〉0.05）;≥40岁组各期PI、RI、S/D值明显高于20～29岁组和30～39岁组。结论：女性卵泡体积、数量以及排卵率随年龄增长呈逐渐降低趋势。     

Skin extensibility time in women. Changes in relation to sex hormones

The influence of female sex hormones on mechanical properties of the skin has been assessed in an in vivo extensometric study. Twenty young (20 +/- 4 years) and 12 middle-aged healthy women (42 +/- 3 years) entered the study. Measurements were carried out on the volar surface of the left forearm on the 10th and 25th day of the menstrual cycle. A significantly decreased skin extensibility time in the pre-menstrual phase was found (25th day) when compared with the 10th day in the young group, while the older one did not reveal significant changes. The data are compatible with an increased water content of the skin noticeable in the pre-menstrual phase and more relevant in young women. In studies on mechanical properties of the skin, changes relative to sex hormones and menstrual cycle need to be taken into account.     

Preoperative skin tumours thickness determination by high‐frequency ultrasound on head and neck region

Background High‐frequency ultrasound is non‐invasive imaging method for examination of skin tumours. Objective The aim of our study was to examine validity of 20‐MHz ultrasound in preoperative determination of skin tumour thickness localized on head and neck region as a potentially useful tool for planning of the surgical intervention. Methods Seventy‐three different skin tumours were preoperatively examined using Dermascan C (Cortex Technology, Denmark) 20‐MHz ultrasound equipment. Maximal vertical thickness of tumours was preoperatively determined by ultrasound, and after surgical excision of tumours, on pathohistological preparations using Nippon–Kogaku ocular micrometre. All patohistological specimens were controlled for presence of tumour cells on specimens’ margins. Results Obtained correlation was very high, r = 0.82, without significant statistical difference (P < 0.01) between dimensions determined by 20‐MHz ultrasound and histometry. There were no pathohistological specimens with tumours cells found on margins. Conclusion Examination of skin tumours by 20‐MHz ultrasound gives reliable additional information about tumour dimensions, sometimes important for therapeutic strategy.     

Nickel contact allergy and menstrual cycle

According to some reports in the literature, the hormonal fluctuations which occur during the menstrual cycle may affect the clinical expression of contact allergy to a greater or lesser degree. In clinical practice, too, patient history often shows exacerbation of the contact dermatitis during the days immediately preceding menstruation. On the contrary, the follicular phase of the cycle seems to have a temporary protective role in inhibiting the eliciting phase of allergic contact dermatitis. One possible explanation for this phenomenon is of immunological type: it has been demonstrated that oestradiol induces inhibition of delayed hypersensitivity type reactions, probably by acting indirectly on cells having a regulatory function in cell-mediated immunity. To investigate any inhibitory effect of the ovulatory phase of the menstrual cycle on contact sensitization, 30 selected fertile women, allergic to nickel sulfate and with a regular menstrual cycle lasting between 25 and 32 days, were enrolled. Patch tests were performed with a series of 10 serial aqueous dilutions of nickel sulfate, from 5% to 0.0013%. The 30 women were tested at 2 different times, in the ovulatory phase (demonstrated by transvaginal ultrasound) and the progestinic phase; they were subdivided into 2 groups of 15 women: in one group, the tests were made first in the ovulatory phase, and in the other, first in the progestinic phase of the menstrual cycle. There was a minimum interval of 5 weeks between the 2 test phases. The study shows that during ovulation the patch tests elicited significantly less intense responses than in the progestinic phase. These data therefore suggest that the ovulatory phase of the cycle has a significant inhibitory role on delayed hypersensitivity type reactions. For this reason, negative responses to patch tests executed in this phase could likely be false-negatives, and after careful evaluation of the phenomenon and of the clinical condition and patient history, it may be considered advisable to repeat the tests during the progestinic phase of the menstrual cycle.     

The vulval vestibular mucosa-morphological effects of oral contraceptives and menstrual cycle

BACKGROUND: An erythematous and hypersensitive vestibular mucosa has been observed during the use of combined oral contraceptives (COC). Hormonal effects on the vestibular morphology have not been studied. OBJECTIVES: Our aim was to evaluate the morphology of the vulval vestibular mucosa during the influence of COC and during the menstrual cycle. METHODS: Forty-five healthy women (20 using COC and 25 not using COC) were included. A 6-mm punch biopsy was obtained from the right posterior vestibule on days 7-11 of the menstrual cycle. A corresponding biopsy was taken 2 weeks later in 16 women without COC. The epithelial morphology was estimated by measuring interdermal papilla distance, dermal papilla to surface, from basal layer to surface and width of dermal papillae. A histopathological assessment was made. RESULTS: The vulval vestibular mucosa of women using COC displayed a larger distance between the dermal papillae (P = 0.04) and a larger space from the dermal papillae to the epithelial surface (P = 0.03) compared with controls in the follicular phase. Women without COC displayed a larger interdermal papilla distance in the luteal phase compared with the follicular phase, P = 0.02. Histopathology showed more superficial blood vessels in the COC users (P < 0.01). CONCLUSIONS: The vulval vestibular mucosa of women with COC display an altered morphological pattern with shallow and sparse dermal papillae compared with the follicular phase. Similar findings are seen in women without COC during the luteal phase which indicate a gestagenic effect on the mucosa. Associations between the morphological pattern and changes in mucosal mechanical sensitivity require further studies.     

High-frequency ultrasound imaging of the skin during normal and hypertensive pregnancies

Background/aims: Diagnosis of preeclampsia is currently made from blood pressure measurements taken at antenatal visits (either at the hospital or in the community). The aim of this work was to see whether the presence of underlying hypertensive diseases is accompanied by changes in the skin of pregnant women, which can be visualized using high‐frequency diagnostic ultrasound. Method: This was a prospective study of pregnant and non‐pregnant, hypertensive and non‐hypertensive patients visiting the outpatient department of a central London Teaching Hospital. The study group consisted of 93 women, of which 30 were non‐hypertensive in the second trimester of pregnancy, 26 were non‐hypertensive in the third trimester of pregnancy, 9 were hypertensive in the second trimester of pregnancy, and 14 were hypertensive in the third trimester of pregnancy. Fourteen non‐pregnant women of comparable age were recruited as controls. Changes in abdominal skin thickness and also skin structure, as analysed by fractal image analysis, was assessed in each patient. Results: In a normal pregnancy, abdominal skin gets thinner as pregnancy progresses. In hypertensive patients, the skin thickness did not appear to alter. Image analysis of abdominal skin scans showed that the skin of non‐hypertensive pregnant women and non‐pregnant women are different. Whereas the analysis of hypertensive pregnant women and non‐pregnant women showed they were the same. Conclusions: The data used to compare the groups indicates that if the abdominal skin of the patient does not get thinner as the pregnancy progresses there is an indication that the patient may be hypertensive. The fractal data comparing the groups indicates the following when comparing a patient’s fractal signature with the non‐pregnant control data: If the abdominal fractal for a pregnant woman is similar to the control group, there is an indication that the patient is hypertensive. It is difficult to predict hypertension in patients, and it is possible that a patient could develop severe preeclampsia between visits to the antenatal clinics. Therefore, if the high‐frequency ultrasound scanner can pick up potential hypertensives early in pregnancy, these women could be identified as potentially high risk.     

有不同分娩方式史的已育妇女在人工流产术中同时放置吉妮致美宫内节育器的临床效果观察

目的 探讨有阴道分娩史与剖宫产史的已育妇女在人工流产术中同时放置吉妮致美宫内节育器(IUD)的临床效果.方法 选择2017年11月至2018年5月在江苏省淮安市妇幼保健院行人工流产的100例已育妇女作为研究对象.根据不同分娩方式史分为A组(n=50,剖宫产史)和B组(n=50,阴道分娩史).两组均在人工流产术中同时放置...     

Pre‐operative ultrasound with a 12–15 MHz linear probe reliably differentiates between melanoma thicker and thinner than 1 mm

Background Pre‐operative determination of primary melanoma thickness could be a tool to identify those patients who could be treated with radical primary tumour excision and sentinel lymph node biopsy in a single procedure. An excellent correlation between sonographic and histological measurement of maximal tumour thickness has been achieved using 20‐MHz transducers. Objective To show that widely available high resolution ultrasound with 12–15 MHz linear probe could also reliably assess the thickness of primary melanoma. Methods Sixty‐nine patients underwent ultrasound evaluation of 70 clinically and dermoscopically suspicious pigmented skin lesions before surgical excision. Results The sensitivity, specificity, positive and negative predictive values of ultrasound to detect melanoma > 1 mm were 92%, 92%, 95% and 81% respectively. The correlation between ultrasound and histological tumour thickness was very good [Pearson’s correlating index 0.823 (P < 0.001)]. Mean difference between sonographic and histological measurements was 0.045 mm with limits of agreement estimated at ?1.4 and +1.49, and a bias between two methods 45 μm. Conclusion Ultrasound examination with a 12–15 MHz linear transducer can reliably differentiate primary melanoma > 1 mm from those ≤ 1 mm.     

Self-reported skin sensitivity in a general adult population in France: data of the SU.VI.MAX cohort

OBJECTIVE: This study aimed to examine the frequency of self-assessed facial skin sensitivity and its different patterns, and the relationship with gender and sun sensitivity in a general adult population. METHODS: A standardized 11-item questionnaire investigating reactions experienced during the past year was developed. The questions explored different patterns of skin sensitivity: pattern I (blushing related to vascular reactivity), pattern II (skin reactions to certain environmental conditions), pattern III (skin reactions after substance contact), and for women pattern IV ('breakout of spots' related to menstrual cycle). Additional items were addressed for women and men, including sun sensitivity. The questionnaire was administered to a large middle-aged population involved in the 'Supplément en Vitamines et Minéraux Antioxydants' (SU.VI.MAX) cohort. RESULTS: Sensitive facial skin was reported by 61% of the women (n = 5074) and 32% of the men (n = 3448), and the frequency decreased with age. The frequency of patterns I, II and III was greater for women (78, 72 and 58%, respectively) than for men (56, 48 and 28%) of comparable classes of age. The frequency of pattern IV was reported by 49% of premenopausal women, and skin reactions after shaving by 41% of the men. Sun sensitivity was found to be a major component of skin sensitivity. Factor analysis showed that individuals with fair phototype frequently evoked reactions associated with pattern I, and skin redness and burning sensations were related to certain environmental conditions (pattern II). CONCLUSION: Skin sensitivity is a common concern that declines with age and is relevant for men as well as for women.     

Cutaneous reactivity to allergens at 24-h increases from the antecubital fossa to the wrist: an echographic evaluation by means of a new image analysis system

To establish the existence of regional variations in response to allergens, we performed patch tests with nickel sulfate 5% pet. at 4 different sites on the volar forearm skin in 17 nickel-sensitive women, aged from 18 to 45 years. After a 24-h application, patch tests were removed and evaluated both by clinical scoring and by means of a 20 MHz ultrasound B scanner. Recorded echographic images referring to uninvolved skin and to positive test sites were evaluated by a traditional image analysis method for the determination of skin thickness. Furthermore, they were processed by software which ascribes arbitrary values to the amplitude levels of the echoes and enables quantification of the pixels, (the smallest elements in a visual display with controllable colour and brightness) forming objects reflecting within a selected amplitude band. Thus, we demonstrated an increase in thickness of uninvolved skin at distal sites and a greater reactivity at 24 h to patch tests in skin areas near to the wrist crease, as evidenced by a greater increase in pixel and in thickness values at distal sites. From our data, we have a clear indication for the use of rotating patterns or symmetrical sites in quantitative and comparative investigations concerning the evaluation of contact allergy on volar forearm skin.     

Successful ultraviolet A1 phototherapy in the treatment of localized scleroderma: a retrospective and prospective study

Background Ultraviolet (UV) A1 phototherapy is an effective anti‐inflammatory treatment modality that influences fibroblast functions. Objectives To document the effects of UVA1 treatment in patients with localized scleroderma (LS) in a retrospective study (at least 6 months after UVA1 treatment) and in a prospective study before and immediately after medium‐dose UVA1 irradiation. Methods In total, 30 patients (retrospective study n = 17, prospective study n = 13) with LS receiving UVA1 phototherapy five times weekly (for 3–6 weeks) were investigated. Improvement was documented using standardized questionnaires and clinical evaluation (using modified Rodnan skin score, Cutometer and 7·5‐MHz ultrasound measurements). Levels of collagen I and collagen III metabolites were measured in serum and urine. Results In the retrospective study, medium‐dose UVA1 phototherapy had been performed 6 months–3 years earlier (cumulative dose 750–1400 J cm^?2; mean ± SD number of irradiations 19·3 ± 3·8). Fourteen of 17 patients (82%) reported an improvement in symptoms following UVA1 therapy. In the prospective study, skin elasticity increased in 77% of the patients following medium‐dose UVA1 phototherapy (cumulative dose 750–1250 J cm^?2; mean ± SD number of irradiations 20·8 ± 4·0). 7·5‐MHz ultrasound measurements showed a mean reduction of lesional skin thickness of 13% compared with skin thickness before UVA1 phototherapy. The ratio of deoxypyridinoline to creatinine was significantly elevated in about two‐thirds of the patients. Conclusions This open study showed a positive short‐ and long‐term efficacy of UVA1 phototherapy in patients with LS, with a reduction in sclerotic plaques, an increase in skin elasticity and a reduction of lesional skin thickness. UVA1 phototherapy had a significant effect on collagen metabolism. UVA1 phototherapy can be regarded as a safe treatment modality for patients with LS.     

黄体酮联合复方玄驹胶囊治疗多囊卵巢综合征所致不孕症的助孕效果及卵巢功能分析

目的:探讨黄体酮联合复方玄驹胶囊治疗多囊卵巢综合征所致不孕症的助孕效果及对卵巢功能的影响。方法:选择2013年12月至2014年12月于我院妇产科门诊就诊的多囊卵巢综合征不孕症患者78例。两组患者均于月经第5d开始服用克罗米芬,1片/d,连续使用5d。对照组在促排卵治疗基础上同时服用黄体酮胶囊,观察组在对照组基础上联合复方玄驹胶囊,两组患者重复上述方案3个月经周期或至妊娠。比较两组患者妊娠率、排卵周期及性激素变化。结果:观察组39例患者中共有20例患者妊娠,未妊娠为19例,妊娠率为51.25%;对照组39例患者中共有13例患者妊娠,未妊娠为26例,妊娠率为33.33%。观察组总例数39例,共75个月经周期,其中治愈、显效、有效、无效的月经周期分别为30个、19个、18个、8个,总有效率为89.33%;其中治愈、显效、有效、无效的月经周期分别为23个、10个、24个、19个,总有效率75%。治疗后,两组患者LH、T、LH/FSH均有所下降,且观察组优于对照组。结论:黄体酮联合复方玄驹胶囊可以有效改善多囊卵巢综合症所致不孕症患者卵巢功能,提高妊娠率,值得临床应用。     

Menstrual cycle and skin reactivity

The hypothesis was tested that a cyclic variation exists in skin reactivity to irritant stimuli. Twenty-nine healthy women with regular menstrual cycles were challenged with sodium lauryl sulfate as an irritant patch test at day 1 and at days 9 through 11 of the menstrual cycle. The skin response to the applied irritant stimulus was evaluated by visual scoring and also quantified by measurements of transepidermal water loss, edema formation, and blood flow in the skin. The skin response to challenge with sodium lauryl sulfate was found to be significantly stronger at day 1 than at days 9 through 11 in the menstrual cycle as evaluated by visual scoring (p less than 0.05) as well as by measurement of transepidermal water loss (p less than 0.05) and edema formation (p less than 0.005).     

Case of autoimmune progesterone dermatitis presenting as fixed drug eruption

Autoimmune progesterone dermatitis is a rare disorder that presents as a cyclical cutaneous eruption during the luteal phase of the menstrual cycle. It typically occurs in women due to an autoimmune phenomenon to endogenous progesterone production. We describe a 34‐year‐old woman with an erythematous round plaque with blistering, which recurred a few days before her menstrual cycle, at the identical site on the left arm. The diagnosis of autoimmune progesterone dermatitis is made with i.d. skin testing on the affected lesion with progesterone. After the beginning of oral prednisolone (40 mg daily) therapy during menstruation, although slight recurrence appeared, the severity was significantly improved.     

Variations in facial skin thickness and echogenicity with site and age.

The characteristic pattern of reflectivity of facial skin, as evaluated by ultrasound, has not previously been described quantitatively. The aim of this study was to evaluate site- and age-dependent variations in skin thickness and echogenicity of facial skin. A total of 40 women, in different age groups, were studied at 12 different facial skin sites. Echographic images were recorded with a 20 MHz B-Scanner and processed by dedicated software. Skin thickness measurements showed significantly higher values on the lower part of the face, whereas skin echogenicity was higher on the upper part of the face. In elderly subjects, an increase in facial skin thickness and overall echogenicity was observed compared with the younger subjects at all assessed skin areas, except the infraorbital regions. Moreover, modifications of skin echogenicity according to age, consisting in the appearance of a subepidermal band and an enhancement of the lower dermis' reflectivity, were observable at most facial skin sites.     

Calculation of nail plate and nail matrix parameters by 20 MHz ultrasound in healthy volunteers and patients with skin disease

Background/aims: The objective, but noninvasive, assessment of the nail plate and nail matrix is of interest in dermatology, and cosmetics as well. These cutaneous structures were investigated with 20 MHz ultrasound. This study was performed to obtain data on normal nails in adults of different age groups, with a left–right comparison, and to investigate nail changes in selected dermatologic diseases. Methods: Healthy controls (n=34) and patients with dermatologic complaints and nail disease (n=37) were included after informed consent. In the control group, 18 woman and 16 men with a mean age of 37.2 years (range 15 to 82 years) were investigated for age‐ and gender‐related differences. Patients with one of the following disorders were investigated: systemic lupus erythematosus (SLE; n=11), systemic sclerosis (PSS; n=8), psoriasis (n=9), chronic hand eczema (n=5), and others (n=4). Measurements of length and width of the nail plate and the lunulae were performed with a micrometer device. Sonography was performed with a 20 MHz probe in B‐scan mode. Results: The mean nail thickness of healthy controls varied between 0.481 mm (right thumb) and 0.397 mm (left fifth finger). The nail volume and the matrix volume disclosed a positive, but mostly nonsignificant, correlation for all controls. Age‐specific differences were investigated for both genders. In men and women, the matrix volume increased significantly with age. The nail and matrix volume was higher in men than in women, independent of age. The left–right comparison disclosed a trend to higher nail and matrix volumes on the right hand. In patients with SLE there was an increase in nail thickness and in matrix volume. Patients with PSS showed a significant decrease in nail thickness and matrix volume. In other diseases the measurements disclosed no confident differences to healthy controls. Conclusion: The 20 MHz ultrasound offers a noninvasive method to calculate nail thickness, nail volume and matrix volume in healthy volunteers and in nail disease. Skin diseases show characteristic quantitative changes in these parameters.