Dermatoscopy: What is it? Utility, Advantages and Dermoscopic Strategies

It allows to obtain a precise and highly amplified image of the spots and store this appearance information for future comparisons.

Dermoscopy, also known as epiluminiscence microscopy, or video dermatoscopy, helps doctors control cancerous skin lesions.

The digital dermatoscopy examination is a diagnostic test in which the skin spots are observed through a magnification camera with a polarized light source connected to a computer system.

Dermatoscopy

A traditional dermatoscopy has several components:

  • A magnifying glass
  • A non-polarized light source
  • A transparent plate
  • A liquid medium between the dermatoscopy and the skin

The typical power of the magnifying glass is 310.

Dermoscopy allows a doctor to observe and analyze skin lesions without obstructing the reflections of the skin’s surface.

Modern forms of dermatoscopy do not use a liquid medium.

 

A dermatoscopy allows dermatologists to distinguish benign from malignant tumors, particularly in the diagnosis of melanoma.

Other cancerous lesions diagnosed by dermatoscopy include angiomas, basal cell carcinomas, cylindromas, dermatofibromas, seborrheic keratosis, and squamous cell carcinomas.

The digital images are taken, stored, and compared with pictures of the patient’s next visit.

  • If the injury changes, it may require excision.
  • If the injury remains the same over time, it is likely to be benign.

A dermatoscopy may 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.

Utility

Dermoscopy is a method used to examine the outer layers of the skin and evaluate pigmented growths of the skin. It is also used to diagnose fungal infections and hair and scalp diseases.

These diseases include alopecia areata, female androgenic alopecia, monilethrix, Netherton syndrome, woolly hair syndrome, pubic lice, scabies, seborrheic wart, and vascular lesions (hemangioma), among others.

It provides a map of the body of all pigmented lesions stored in the computer system, which facilitates personalized monitoring of the development of moles in each patient.

The digital dermatoscopy examination is more used in the following cases:

  • Patients with a high number of freckles or with numerous atopic moles.
  • Patients with a personal or family history of skin cancer (mainly malignant melanoma ).
  • Patients with dysplastic nevus syndrome (freckles with dynamic changes and risk of transformation).
  • Elderly patients.

Advantage

Dermatoscopy involves magnifying the skin’s structure and allows much more detailed observation of the skin that can not be done with the naked eye.

Dermoscopy is a specific test that reduces the frequency of unnecessary removal of warts.

Digital dermatoscopy offers new and better opportunities to inspect the observed lesions dynamically and avoid the subjectivity of the dermatoscopic analysis when saving the images in an electronic device and storing them in a database.

Digital dermatoscopy turns out to be the most useful diagnostic method for patients who have many pigmented nevi (moles) that should be followed up every six months.

With this objective in mind, a unique program is applied to each person to map the skin of pigmented nevi.

It allows the accurate detection of any change in the size, color, edges, and structures of the lesions.

It leads to a reasonable and easy screening for the prevention of skin cancer by detecting the suspicious lesion and eliminating it at the earliest stage.

The particular dermoscopic structures suggest melanoma; some include an atypical network, veins, irregular spots and globules, pupa-like structures, irregular spots, and blue-white structures.

Dermoscopy allows the visualization of structures within the epidermis and papillary dermis that are usually invisible to the naked eye.

Dermoscopic strategies

The dermatoscopic diagnosis of melanoma can be made following one of several strategies.

First, physicians can choose from many established analytical and diagnostic algorithms, such as the ABCD (Asymmetry, Borders, Colors, Differential Structural Components, or Dermatoscopic Structure) rule.

Or also the CASH algorithm (Colors: few versus many, Architecture: order vs. disorder, symmetry vs. asymmetry, homogeneity vs. heterogeneity) to distinguish malignant from benign pigmented lesions.

With the algorithm approach, a calculation is made based on the number of specific melanoma structures present; a biopsy is recommended if a certain threshold is reached.

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 “the 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.

The dermatoscopic changes in the lesions are evaluated successively; this involves capturing a dermoscopic image at the beginning of the study and comparing it with an image captured during the follow-up appointment.

This technique is used in cases where a lesion may appear suspicious in dermatoscopy but does not meet the diagnostic criteria in any of the algorithms or strategies described above.

The approach for managing these lesions is the “short or long term monitoring of moles” if at the beginning it does not present features of classic dermatoscopic melanoma, or with the monitoring time there are no changes, it is not necessary to perform a biopsy.

The short- and long-term moles monitoring aims to decrease unnecessary biopsies while detecting as many melanomas without traits as possible.

As the evidence supporting the use of dermatoscopy in clinical practice has grown, so has the instruction and service of the technique.