Diagnostic Applicability Of In Vivo Confocal Laser Scanning Microscopy In Pigment Lesions And Skin Tumors

PartⅠObservation and evaluation of the physiology of normal skin by CLSMObjective To measure and evaluate the correlated indexes of the live human skin and study the regional variationsin by confocal microscope in vivo.Methods In vivo confocal laser scanning microscopy was performed in 100 adults(52 males,48 females) of various skin phototypes.Five topographic sites were studied in each subject:forehead,cheek,inner and outer forearm surfaces and lowerback after contrast with the slides of histopathology.Thickness of stratum corneum,stratum granular,stratum spinosum,basal layer and epidermal thickness at suprapapillary epidermal plates was measured during real-time imaging.The number and diameter of epidermal keratinocytes in each epidermal cell layer as well as the characteristics of dermal papillae were defined from the grabbed images.Results Stratum corneum appeared brighter in sun-exposed than in sun-protected areas and particularly pronounced in heavily pigmented individuals.The epidermal thickness at the suprapapillary epidermal plate,was greater in sun-exposed areas than in sun-protected sites except forearm exor surface.The thickness of every epidermis layer varies from 1.6 -11.1 um(mean 7.065±1.14) in stratum corneum,3.2-14.3 um in stratum granular(mean 8.32±1.36 ) to 10.4-29.3um stratum spinosum,(mean 19.32±2.86).The minimum thickness of the epidermis is 30.6～48.8um(mean 34.7±2.13)(p＜0.05).The en face numerical density of granular keratinocytes(20.7～39.6um,mean 30.62±4.33) is greater on the face as compared with all other sites,whereas the surface density of spinous keratinocytes(diameter 14.4～24.7um,mean 20.19±2.22 ) is greater on sun-protected sites.Additionally,the number of basal keratinocytes per millimeter length of dermoepidermal junction is greater in sun exposed areas. Interestingly,the dermal papillae shape varies and their sizes increase in circumference from sunexposed to sun-protected sites,as observed at a specific depth below the stratum corneum.Conclusion The thickness and the diameters of different epidermis layers varies in the sites.Stratum corneum and stratum granular is thicker in the sun-exposed sites and the diameters of different layers are greater in the sun-protect sites,which indicates the influence by the enviroment.In summary,our results demonstrate that near infra-red confocal microscopy is a feasible tool for microscopic analysis of skin morphometry in vivo,and set a serial indexes for the next study of the skin diseases.PartⅡThe application of CLSM in the diagnosis and follow-up in the pigment diseasesObjective To determine the correlated indexes of the melanin distribution in the epidermis measured by CLSM and evalutate the application of CLSM in the follow-up ofmelasma and differential diagnosis ofvitiligo and amelanotic nevus.Methods In vivo confocal laser scanning microscopy was performed in 100 adults(52 males, 48 females) of various skin phototypes.Five topographic sites were studied in each subject:forehead,cheek,inner and outer forearm surfaces and lowerback after contrast with the slides of histopathology.Diameter,density and brightness of the melanin caps in the basal layer keratinocytes were measured.Patients of melasma were followed up after therapy by Nd:YAG laser to detect the histologic characteristics.Analyses about the diagnosis indexes of vitiligo and amelanotic nevus were carried out for evaluation of the specificity and sensitivity.Results Melanin caps were generalized in the basal layer keratinocytes while the melanocytes were rare.The clinical score correlated well with the CLSM score both in the baseline and in the improvement during the follow-up of the melasma patients treated by the Nd:YAG laser.The melanin caps clasped after treatment at half an hour,and the granules were discharged to the upper layer gradually and the dendritic melanocytes were detected in 2-4weeks after the therapy.Area of the melanin distribution(A),score of brightness＞3(B),clear border of the lesions(C) and density of melanin≤30%(D) were the main differential indexes for vitiligo and amelanotic nevus.The specificity and sensitivity varied from 80%～92.5%,58.06%～81.7%separately, which could be improved significantly by the combination of different two indexes. Conclusion Images of CLSM could act as an feasible and reliable tool for the evaluation of melasma.The exist of dendritic melanocytes may be a foundation for the relapse after the laser therapy.Characters of ABCD were indicated to be important in the differential diagnosis of vitiligo and amelanotic nevus.PartⅢIn vivo diagnosis of the basal cell carcinoma and actinic keratoses by CLSMObjective to explore the sensitivity and specificity of CLSM for diagnosis of basal cell carcinoma and actinic keratoses.Methods This was a retrospective study of CLSM images of 72 suspected BCC lesions representing a variety of benign and malignant diagnoses and 34 definite AK skin lesions.These lesions were examined clinically,with biopsies recorded for all the 33 BCCs detected.Images of CLSM were contrasted with the histopathology to induce the criteria.Blinded retrospective analysis of the images from the lesions was carried out by the criteria to determine the specificity and sensitivity for diagnosis.Results A set of 5 histologically correlated confocal imaging criteria for diagnosing BCC and AK respectively were established. The presence of elongated monomorphic nuclei,polarized nuclei,increased vasculature,pleomorphic epidermis and WBC infiltration were the criteria for BCC. Polarized nuclei and elongated monomorphic nuclei got the higher specificity(97.4 %) and sensitivity.The specificity increased gradually by cumulating of different criteria until 100%with the total five.18 of 29 lesions(62.1%) suspected highly by clinic doctors were ascertained to be BCC,while the percentage was improved by CLSM to 93.1%.Hyperkeratinization,atypical hyperplasia of keratinocytes, inflammation infiltration,increased vasculature and actinic elastotic degeneration were the criteria for AK.atypical hyperplasia of keratinocytes had the highest specificity(83.3%) and sensitivity(97.1%).Conclusion CLSM offers a sensitive and specific tool for the noninvasive diagnosis of BCC and AK in vivo.