Practical Considerations and Techniques for Skin Biopsy

What is a skin biopsy? It is a diagnostic method that involves the removal of a small skin sample for testing. A practitioner places it under a microscope to check for skin infections, cancer, or skin disorders like psoriasis. And depending on the size and site of the lesion, a doctor can use various methods of performing a skin biopsy. 

When you use the proper technique for performing a biopsy and choose the right lesion, you get a better interpretation of this procedure. This process is usually safe, but there are chances of bleeding, scarring, and infection using the basic infrastructure.

Bleeding

Bleeding may occur in skin biopsy, and it’s more common in older people with atrophic skin. It usually happens on the scalp and genitals. 

You can prevent bleeding by checking if there are underlying vessels in the biopsy area. And then avoid using such an area. 

Since bleeding usually occurs because of venules rupture, pressuring the area for two to three minutes may stop the bleeding.  

Also, you can soak a swab in hydrogen peroxide and use it to stop the oozing, or aluminum chloride 20–40%.  

Scarring 

Before any surgery, one should ensure not to have a history of keloidal tendency or hypertrophic scars. 

Infection

One must not worry about the infections during skin biopsy if they adhere to proper aseptic precautions. The chances of getting infected are minimal. Applying topical antibiotics and systematic agents can also work for patients with uncontrolled diabetes mellitus. 

Practical Deliberation To Improve the Outcome of Skin Biopsy 

What’s the best volume of formalin solution and optimum strength? 

The concentration of formalin for fixation must be 10 percent. Since the commercial formalin available is 40 percent, you have to dilute this with water at the ratio of 1:4. 

And the required volume of 10 percent formalin for optimal fixation is ten times the biopsy specimen volume. 

A skilled practitioner must proficiently handle tissue transfer from the biopsy wound to the formalin container. Otherwise, this can crush and compress the tissue rising to compression artifact after processing. 

Various Techniques Of Skin Biopsy 

Punch Biopsy

It’s one of the popular techniques used for a skin biopsy. It can work for diagnostic as well as therapeutic purposes. The ideal device for these biopsies is a 4 mm diameter punch. And this provides the required tissue sample for histopathology assessment. Using a smaller tool would yield insufficient tissue, risking the diagnosis’s accuracy. 

Shave Biopsy

Shave biopsy is the most preferred technology for solitary raised lesions or where there is a restriction of pathology to the epidermis. It’s suitable for squamous cell carcinomas (SCC) and superficial basal cell carcinomas (BCC). 

Using a blade, a practitioner shaves off the portion of the lesion above the level of the surrounding skin. 

The appropriate shave biopsy depth requires a balance between diagnostic accuracy and cosmetic result.

Saucerization Biopsy

This skin biopsy is ideal for vesiculobullous disorders and epidermal neoplasms. It’s a technique in which the cleavage plane passes through the reticular dermis and the subcutaneous tissue.

A practitioner will first apply anesthesia to the target area before using the shaving blade. He ensures to bend the device in an arc shape by holding it between the thumb and the index finger. Then in this manner, the tool goes through the dermis and shaves the lesion. And he dresses the wound to heal.

Incisional Biopsy

When your doctor suspects an inflammatory dermatosis, he will perform a skin biopsy by taking a part of the tissue to confirm the diagnosis.  

Excisional Biopsy

This skin biopsy requires skill and more time than other biopsy techniques. It yields more tissue for the dermatopathologist allowing and requiring multiple studies.

An excisional biopsy is an essential procedure for suspected melanomas, deep dermal tumors, and deep inflammatory processes. It’s an ideal technique when doctors suspect neoplasm. 

They remove the entire lesion, including the subcutis plane. Then close the wound with sutures and leave it to heal.

Wedge Biopsy

Wedge is the best technology for subcutaneous mycosis, tuberculosis verrucose cutis, etc. It’s ideal for large lesions where the specimen’s length, breadth, and depth are critical. 

After a practitioner anesthetizes the skin, he makes a stab incision in a V or a triangular shape using a scalpel blade 11 or 21–25. And this extracts a cone of tissue and leaves the lesion to heal by secondary intention.

In Conclusion

skin biopsy may be a simple procedure, but it is of great diagnostic value. However, being knowledgeable of the practical aspects of different techniques and awareness of possible complications is ideal. Good postoperative care helps reduce the risk of complications. It’s appropriate to dress the biopsy sites with a moist occlusive dressing and paraffin ointment. And this should remain undisturbed for 24 to 48 hours.