Also known as epiluminescence microscopy, it is the study of skin lesions with a dermatoscope.
A traditional dermatoscope has several components, including a magnifying glass, a non-polarized light source, a transparent plate and a liquid medium between the dermatoscope and the skin. The typical power of the magnifying glass is 310.
The dermatoscope allows a doctor to observe and analyze skin lesions without obstructing the reflections of the skin surface.
Modern forms of the dermatoscope do not use a liquid medium.
Polarized light is used to cancel reflections from the surface of the skin and is connected to a computer.
A dermatoscope allows dermatologists to distinguish benign from malignant tumors, particularly in the diagnosis of melanoma .
Other cancerous lesions that can be diagnosed by dermatoscopy include angiomas, basal cell carcinomas, cylindromas, dermatofibromas, seborrheic keratosis, and squamous cell carcinomas .
With the use of digital dermatoscopy, also known as video dermatoscopy, the digital images that are taken are very precise and amplified, they can be stored and compared with the images of the patient’s next visit.
It allows the identification in a high degree of skin lesions and perform the differential diagnosis . If the injury changes, it may require excision. If the injury remains the same over time, it is very likely to be benign.
A dermatoscope can also allow doctors to determine the surgical margin for skin cancers that are difficult to define.
Bowen’s disease, lentigo maligna and superficial basal cell carcinoma belong to this category because they are known to have indistinct margins.
Dermoscopy is also used in the diagnosis of fungal infections, hair and scalp diseases (including alopecia areata, female androgenic alopecia, monilethrix, Netherton syndrome and woolly hair syndrome), pubic lice, scabies and warts
The digital dermatoscopy provides a map of the body of all pigmented lesions, which is stored in the computer system, which facilitates personalized monitoring of the development of moles in each patient.
The diagnoses that are made through digital dermatoscopy are used to evaluate the signs of malignancy of the lesions.
The digital dermatoscopy is used for the following cases:
- Patients who have a high number of moles and freckles on their skin.
- Patients with personal or family history of skin cancer (mainly melanoma).
- Patients with dysplastic neon syndromes .
Dermoscopy is a method used for the detailed examination of the outer layers of the skin and the evaluation of pigmented skin growths such as moles, seborrheic warts, vascular lesions (hemangioma), skin carcinoma.
The objective of the test is to differentiate between malignant and non-malignant pigmentation and to help in the timely diagnosis of skin cancer and its prevention.
This type of examination is recommended during a skin cancer prevention consultation for elderly patients, those who have numerous atopic moles or those who have a family member diagnosed with malignant melanoma.
Dermoscopy involves the use of a dermatoscope that magnifies the structure of the skin and allows a much more detailed observation of the skin that can not be done with the naked eye.
Dermatoscopy is a specific examination that reduces the frequency of unnecessary removal of warts.
Digital dermatoscopy offers new and better opportunities to dynamically inspect the observed lesions and to avoid the subjectivity of the dermatoscopic analysis when saving the images in an electronic device and storing them in a database.
The digital dermatoscope turns out to be the most useful diagnostic method for patients who have many pigmented nevi (moles).
With this objective in mind, a special program is applied to each person to map the skin of the nevi that must be followed every 6 months.
The dermatoscopic diagnosis of melanoma can be made following one of several strategies.
First, physicians can choose from many established analytical diagnostic algorithms, such as the ABCD (Asymmetry, Borders, Colors, Differential Structural Components or Dermatoscopic Structure) rule.
Or the CASH algorithm (Colors: few versus many, Architecture: order against disorder, Symmetry against asymmetry, Homogeneity against heterogeneity), to distinguish malignant lesions from benign pigmented ones.
With the algorithm approach, a calculation is made based on the number of specific melanoma structures present, if a certain threshold is reached, a biopsy is recommended.
The second option is based on the concept of the “ugly duckling”, whereby a lesion that stands out from the surrounding lesions, even if it seems banal, should raise suspicions.
A third option is to use the sign “beauty and the beast”, the dermoscopic pattern of the lesion is compared with nine typical recurrent benign patterns, and if it deviates from any of these patterns, a biopsy is suggested.
Advantages of digital dermatoscopy
The advent of digital dermatoscopy has allowed physicians to evaluate dermatoscopic changes in lesions in a manner similar to how doctors routinely follow clinical changes.
This involves capturing a dermoscopic image at the beginning of the study and comparing it with an image captured during a follow-up appointment.
This technique has been used in two situations:
First, it has been used in cases in which an injury may appear suspicious in dermatoscopy but does not meet diagnostic criteria in any of the algorithms or strategies described above.
The approach to the management of these lesions, called “short-term mole monitoring”, was proposed by Menzies.
Secondly, digital monitoring of dermatoscopy has been used in patients with multiple clinically atypical moles, who have a high risk of melanoma.
The concept of long-term dermatoscopic monitoring was introduced by Kittler.
The goal of both short-term and long-term monitoring is to decrease unnecessary biopsies as much as possible.
It allows the objective detection of any change in the size, color, edges and structures of moles.
It leads to an opportune and easy screening for the prevention of skin cancer by detecting the suspicious lesion and eliminating it at the earliest stage.
With digital dermatoscopy, the visualization of structures within the epidermis and the papillary dermis that are normally invisible to the naked eye is allowed.
The particular dermoscopic structures are suggestive of melanoma; some of these include an atypical network, veins, irregular spots and globules, pupa-like structures, irregular spots and blue-white structures.
Multiple studies have supported the use of this device in the treatment of patients with pigmented lesions.
Digital dermatoscopy increases the accuracy in the diagnosis of melanoma by 49 percent compared to the naked eye examination.