Bone biopsy

Bone biopsy is a medical procedure during which a small sample of bone tissue is taken and examined for the presence of cancer cells, infections or any other bone disorders. Bone biopsy involves removing the hard outer portion of the bone from the compact tissue, unlike bone marrow biopsy procedure where the innermost sponge-like material containing marrow is removed to assess for abnormalities.

Why is bone biopsy conducted?

Tests like x rays and bone scans may reveal a tumor, but whether it is benign or malignant and if it is malignant, the type of cancer cell is detected accurately by bone biopsy. Bone biopsy determines the presence of benign tumors like Fibroma, Osteoblastoma, Osteoid osteoma and cysts and cancerous tumors like Ewing's sarcoma, Multiple myeloma and Osteosarcoma. Apart from tumors, bone biopsies are also used to identify the bone infections like osteomyelitis and abnormal bone structures that may be causing persistent pain and tenderness.

Types of bone biopsy

Closed biopsy or needle biopsy involves inserting a needle through the skin into the bone to draw a small bone tissue with the needle. Closed biopsy is performed under imaging guidance using a variety of modalities such as fluoroscopy, CT and MRI. Firstly the doctor will choose the bone, mostly the one that is closer to the surface such as hip bone, but biopsy can be performed on any bone. The area is sterilized with antiseptic lotion and local anesthesia is administered. It is important for the patient to remain motionless during the procedure; he may be strapped or belted to restrict movement.

A small incision is made at the site through which the needle is drilled till it finds bone. Needle will be wriggled into the bone to obtain the sample. After the needle is withdrawn, gentle pressure is applied on the site to control the bleeding; finally, the area is cleaned and covered with the bandage. The tissue sample is sent to the laboratory for analysis.

Open biopsy procedure takes place during surgery after administering general anesthesia. Here, the size of the incision is relatively larger as a small piece of bone is removed from the patient's body for further examination.

The patient is required to undergo few blood tests before the procedure to assess the blood clotting and the functioning of kidneys and liver. Medications like blood thinners and anti platelet drugs may need to be stopped temporarily. The site of the biopsy may feel sore and tender for few days and patient may be given pain relievers. If it is a closed biopsy, the patient can return home within an hour or as soon as he starts feeling comfortable. In the case of open biopsy, the patient will regain consciousness after few minutes but may feel drowsy for few hours after the procedure and is retained in the hospital for the whole day. Whether it is needle or open biopsy, patient should keep the area of biopsy bandaged and dry to avoid infections.

Complications arising from bone biopsy are rare, yet patient should be aware of the risks associated with the bone biopsy. Patient may contact skin infection or suffer from bone infection. There is also a risk of needle breaking the bone and causing injury. Hence whenever there is bleeding, redness or oozing of the pus or fever, pain and chills, it should immediately be brought to the doctor's notice.

Muscle Biopsy

This is a procedure in which muscle tissue is removed from an organism and examined microscopically. Muscle biopsies can distinguish between Myopathies, (the pathology is in the muscle tissue itself) and neuropathies (pathology is at the nerves innervating those muscles) by means of microscopic analysis. Problems could be detected in a nervous system, in connective tissue, vascular or musculoskeletal system. A variety of Myopathies can cause centronuclear biopsy and hence a specific genetic testing becomes increasingly important.

What is muscle biopsy?

This is a procedure when a small sample of tissue is removed for testing in a laboratory. The test detects an infection or disease in the muscles. This is a relatively simple procedure. It is done as an outpatient basis, and the patient is free to leave on the same day as the procedure. As it is often done on a local anesthesia, the doctor removes the tissue from the area but the patient remains awake for the test.

Reasons for a muscle biopsy

This is done when the doctor suspects an infection in the muscle. The biopsy is done to help the doctor rule out certain conditions that could cause the symptoms and then proceed with an appropriate treatment plan.

• Biopsy is done if the doctor suspects that there may be defects in the way the muscles metabolize or use energy.
• Diseases that affect the blood vessels and connective tissues, where the arteries become swollen.
• Infections related to the muscles, such as the one caused by a type of roundworm.
• Muscle disorders including muscular dystrophy, genetic disorders that lead to muscle weakness.

Risks of a muscle biopsy

There is always a risk of infection or bleeding or bruising possible when a medical procedure that breaks the skin is performed. However, since the incision here is quite small, especially in needle biopsy, the risk is much lower. An electromyography is done in case of recent muscle damage. Very rarely there could be damage to the muscle where the needle is inserted.

Muscle biopsy procedure

There are two ways in which muscle biopsies are performed - the common method is called a needle biopsy and for this procedure, the doctor inserts a thin needle through the skin and remove the muscle tissue. This could be:

Core needle biopsy with a medium sized needle, similar to the way core samples are taken from the earth

Fine needle biopsy using a thin needle attached to a syringe, fluids and cells are drawn out.

Image-guided biopsy where the needle biopsy is guided with imaging procedure; such as x rays and CT scans.

Vacuum assisted biopsy uses suction from a vacuum to collect more cells.

The patient receives a needle biopsy after a local anesthesia and will not feel any pain or discomfort. There will be pressure in the area where the biopsy is taken and the area may be sore for about a week. In case the muscle sample is far to reach and is in deep muscles, the doctor may choose to perform an open biopsy. The doctor will make a small cut in the skin and then remove the muscle tissue from there.

For instance, if patient needs have a biopsy in the leg, he/she must expect to use crutches or another assistive device for two full days after biopsy. Training with crutches is provided. Some patients may need assistance at home during the recuperation period. If patients have had a biopsy in the arm, they must expect to wear a sling for two days. Stitches do not need to be removed but must remain completely dry for a couple of days.

In general, there are few complications and the resulting scar heals well. After the tissue sample is taken, it is sent to a laboratory for testing and the results would be ready in a couple of week's time. A report on frozen or paraffin specimens will be sent to the referring physician. The small piece of muscle tissue is examined by microscopic techniques to check for presence of fibrous tissue or other abnormalities. The extracted tissue can also be stained for detecting absence of presence of particular proteins. Microscopic examination can also reveal if the muscle fibers are being infiltrated by the immune system.

In case the results are abnormal, it could mean there is an infection or disease in the muscles and this may cause them to weaken or die. The doctor may prescribe additional tests to confirm the diagnosis and how far the condition has gone. Treatment options are discussed and further steps taken.

Skin Biopsy

A biopsy of the skin is done to clear what is the condition of the skin such as psoriasis, to diagnose a disease such as skin cancer and to diagnose any bacterial or fungal skin infection. A skin biopsy is routinely done in a doctor's clinic as an outpatient procedure. You have to inform the doctor if you suffer any allergies to medications, especially any adverse reactions to local anesthetics or to iodine cleaning solutions. Keep the doctor informed if you are under any medication, are pregnant or suffer bleeding problems.

Skin biopsy procedures

If it is an excision biopsy, the entire suspect skin is cut out. Excision is normally done with a scalpel and the incision is closed up by stitches. If it is a punch biopsy, a sharp cutter is used to remove a small cylinder of skin. Stitches are made to close this type of biopsy wound as well. Such punch biopsies are quick, convenient and done for small wound. A pathologist can get a full thickness view of the skin. Sometimes more than one punch biopsy is necessary. The punch biopsy blade takes a small round core of tissue ranging from 2-6mm dia although 3-4mm is the usual size.

In a shave biopsy, the outermost part of a lesion is shaved off with a scalpel. Only if the top layer of the skin is suspected, a shave biopsy is adopted. A dermatologist will take a superficial slice of skin from the area of affected with a scalpel, dermablade or a razor blade. Although there are no stitches required, there will be a small scar that should heal in about a week's time. An aspiration is used to remove the skin that is fluid filled and not solid. The doctor inserts a small needle attached to a syringe into the lesion and the fluid is sucked out.

The biopsy site is cleaned with an iodine type solution with alcohol and with a sterile soap solution. A sterile towel is placed around the area once the skin is cleaned. A local anesthetic is injected into the skin to make it numb. You may feel a brief prick and stinging sensation as the medicine is injected. The doctor can perform the biopsy once the skin is numb. Now the tissue is removed and sent to the laboratory for analysis by a pathologist. If needed, the wound is stitched up.

A bandage is wound over the biopsy site. You may also be advised to wash the wound and apply antibacterial ointment and change the bandage daily. If you experience any pain in the biopsy site, consult the doctor about medication to relieve it.

• Unexpected bleeding may occur; especially if you are on any blood thinning medications such as aspirin. For instance, arterial puncture on the forehead or temple may take time to stop bleeding.
  
  
• There could be wound infections in about 1-5% of surgeries. There could be ulcerated or crusted skin wounds. Antibiotics may be used to clear this up.
  
  
• Infection is also common in diabetics, elderly patients and those on immunosuppressive medicines.
  
  
• If large scars, called keloids, there is an increased chance of forming a scar over the biopsy site.