Advanced Methods Of Surgery And Radiology Important Question And Answers

Advanced Methods Of Surgery And Radiology

Question 1. Write a short note on the CT scan.
Or
Write briefly about the CT scan.

Answer. Computed tomography scan was invented by Godfrey Hounsfield in 1963.

Working on Ct Scan

Narrow X-ray beams are passed from the rotating X-ray generator through the gantry where the patient is placed.

When X-rays pass through the tissues, some of the X-rays get absorbed, and some pass through, depending on the tissue density, different grades of absorption in different tissues are detected through sensitive detectors which are translated to a Grayscale image by a computer.

The density of tissues is numbered as Hounsfild Number (HN).

Read And Learn More: General Surgery Questions and Answers

CT scan Contrast agents

• Ionic: Water soluble iodide dyes such as sodium diatrizoate, and meglumine iothalamate.
  They are cheaper but often toxic and cause anaphylaxis.
• Non-ionics are safer but expensive like Iohexol and Iopamiro.

CT scan Indications

• Trauma-like head injury, chest injury. Abdomen trauma.
  In trauma, only a plain CT scan is taken.
• Neoplasms: To see the exact location, size, vascularity, extent, and operability.
• Inflammatory conditions: In various sites such as in the pseudocyst of the pancreas.

CT scan Contraindications

• In pregnancy.
• In restless patient.

CT scan Advantages

• 1 to 2 mm-sized sections are possible.
• The amount of exposure to radiation is less
• More accurate, sensitive, and specific.
• Small lesions are detected.

CT scan Disadvantages

• Interpretation by experienced radiologists is done
• Artifacts can be present
• The cost is high.

 

Question 2. Write a short note on the biopsy.

Answer. A biopsy is the removal of tissue from a living organism for microscopic examination and diagnosis.

Types Of Biopsy

• Excisional biopsy: If a lesion is excised for histological evaluation it is called an excisional biopsy.
• Incisional biopsy: When only a small section of tissue is removed from the lesion for histological evaluation it is called as incisional biopsy.
• Fine needle aspiration cytology (FNAC): It is done by aspirating tissue material inside a lesion which is later on diagnosed microscopically after preparing a smear.
• Frozen section biopsy: It is performed to get an immediate histological report of a lesion.
  The tissue is obtained from the lesion and is kept in deep freeze and then frozen tissue is sectioned and stained to get a prompt diagnosis.

Procedure of Biopsy

• Anesthesia: Give a block to anesthetize the region where the specimen is to be obtained.
  Local infiltration and injections into the tissue which should be biopsied should be avoided as it leads to the artifacts in the specimen.
  If a block is not effective give local infiltration at least l cm away from the lesion.
• Stabilization of tissue: Soft tissue biopsies are done over the movable tissues of the oral cavity, i.e. tongue, lips, etc.
  The dental assistant stabilizes the tissue by stretching it.
• Hemostasis: Gauze pieces are the best means for compressing the tissue and achieving hemostasis.
  A gauze piece can also be placed to cover the mouth of the suction tip and is used to prevent the specimen from being sucked inside.
• Incisions: Use a sharp scalpel. Provide two incisions which form an elliptical incision and converge to form a V at the base, this provides a good specimen and a wound that is easy to close.
  Alternatively, a triangular-shaped incision can be made which converges in the form of a tip of a pyramid at the base.
  Incisions should be given parallel to the nerves and vessels in that region to avoid damage.
• Handling of tissues: Tissue that has to be removed should be handled carefully so that histopathological examination can be performed.
  A non-toothed tissue-holding forceps is used and care is taken not to crush the tissues.
• Care of specimen: After removal of the tissues, the specimen is transferred to a bottle containing 10% formalin which should be at least 20 times the volume of the specimen obtained.
• Surgical closure of wound: Primary closure is possible in most cases. Where it is not possible, the tissues are undermined to facilitate closure.

 

Question 3. Write a short note on FNAC.
Or
Write a short note on fine needle aspiration cytology.

Answer.FNAC is also called fine needle aspiration cytology.

• FNAC is the microscopic examination of aspirate which is obtained by penetrating a fine needle in the lesion.
• FNAC is a procedure for rapid diagnosis.

FNAC Procedure

• Position the needle over the target area in the lesion.
• As the needle is penetrated and is positioned a plunger is pulled to apply negative pressure.
• Negative pressure should be released as the needle remains in the target tissue.
• The needle is withdrawn and defamed air is withdrawn outside.
• A drop of aspirate is taken on the slide and is thoroughly spread.
• Fix the slide by keeping it in 95% of alcohol for one hour.
• Staining with PAP stain should be done.

FNAC Indications

• Help in the diagnosis of swellings of the head and neck region.
• Part of initial diagnostic work-up of lymphadenopathy, metastatic lesion, or lymphomas.
• Helps in distinguishing benign from malignant and cystic lesions from inflammatory lesions.
• Aids in diagnosis for salivary gland pathologies.
• Helps to identify the cause of enlarged lymph nodes.

FNAC Advantages

• It is minimally invasive.
• It is a safe, fast, and cost-effective method.
• It is less time-consuming.
• It does not spread the tumors, or disrupt the field for surgical dissection.

 

Question 4. Write briefly on Laser.
Or
Write a short note on Laser in surgery.

Answer. Molecules are placed in a compact area and power is passed through this to activate the molecules.

Molecules get activated at different periods and move in different directions, which they hit to each other releasing energy.

This energy is allowed to act through the optical system to the area, wherever required. It is named depending on the molecules used:

• Argon Laser.
• Neodymium Yttium Aluminum Garnet Laser (Nd: YAG Laser)
• CO2 Laser.
• Neon Laser.
• Holmium Laser.
• Erbium Laser.

Uses Of Laser

• In cranial surgery in children.
• In ENT it is used to treat vocal cord lesions and laryngeal lesions.
• In ophthalmology, it is very useful in retinal surgery
• In general surgery:
  • In bleeding duodenal ulcer.
  • For palliative decoring of tumors in carcinoma esophagus.
  • In carcinoma of the rectum.
  • In the treatment of hemorrhoids (first and 2nd degree).
  • In resection of bladder tumor.
  • In cervical cancer.
  • To achieve a bloodless field.
  • Often making incisions in the abdomen and other places.

Laser Precautions

• All reflecting instruments should be avoided otherwise laser gets reflected and injures normal tissues or the working team in the OT
• All should wear protective spectacles to their eyes.

Laser Advantages

• Provide bloodless field
• It is fast
• Small lesions can be removed easily and completely.

Laser Disadvantage

Availability and cost factors.

 

Question 5. Write a short note on cryosurgery or laser surgery.

Write a short note on cryosurgery.

Answer.

Cryosurgery

• It is the method of destruction of tissues by controlled cooling.
• It consists of an automatic defrosting device with a cryoprobe.
• Commonly nitrous oxide is used as it is easily available, cheaper, and has the optimum temperature required for other procedures.
• Other gases used are CO2, Liquid nitrogen, and Freon.

Cryosurgery Mode of action

• It produces intracellular crystallization, dehydration, and denaturation of proteins and cell death.
• It causes the obliteration of microcirculation and so cell death.

Cryosurgery Indications

• To remove warts and lesions in the skin.
• Cryotherapy for piles.
• For chronic cervicitis.

Cryosurgery Advantages

• Relatively bloodless and painless.
• Adequate control of extent and depth in freezing
• Equally effective.

Cryosurgery Disadvantages

• Can cause infection.
• Discharge from the site.

 

Question.6. Write a short note on brachytherapy.

Answer. It is radiation given with a source close to the tumor.

• It is given using iridium192 caesium137.
• It is curative radiotherapy.
• It is used in carcinoma of the oral cavity, penis, breast, cervix, and bladder.
• Radiation material placed in the cavity is called intracavitary radiotherapy.
• Radiation material is inserted into the tissues through interstitial radiotherapy.
• Implants can be kept permanently or temporarily.
• Radioactive material is placed into the cavity/tissue through applicators under general anesthesia.
• Intraoperative radiotherapy is also becoming popular. It has only a localised effect with adjacent tissue being spared.

Brachytherapy Advantages

• High, localized, continuous dose of radiotherapy.
• Deeper and adjacent tissues get spared
• The dose rate is high in a short time.
• Side effects are less
• It is curative and effective in early cancers.
• Surgery is avoided and part is retained.

Brachytherapy  Disadvantages

• Technique is diffilt.
• Availability of facility.
• Produces local complications such as displacement/erosion.

 

Question 7. Describe briefly the different types of biopsy.

Answer. Following are the different types of biopsies:

• Incision biopsy—wedge biopsy
• Excision biopsy
• Trucut biopsy
• Pap smear
• FNAC
• Frozen section biopsy
• Punch biopsy
• Ultrasound-guided biopsy
• Brush biopsy
• Laparoscopic biopsy
• CT-guided biopsy
• Thoracoscopic biopsy
• Endoscopic biopsy (gastroscopic or colonoscopic or through ERCP or cystoscopy)
• Bronchoscopic biopsy
• Open biopsy either laparotomy thoracotomy or craniotomy using
• Dancly’s brain cannula

Incision Biopsy

• This is the excision of a portion of the lesion for microscopic examination.
• This method is employed on large, diffuse lesions which has a size of 2 cm in its greatest dimension.
• This method can also be done on lesions suspected of malignancy.
• This method aims to remove a portion of the lesional tissue in question along with the sample of normal adjacent tissue for comparison.

Types Of Incision Biopsy

• Punch biopsy: This is done by using a surgical punch of diameter 4, 8, or 10 mm. This incisional biopsy is done in mass screening programs.
• Wedge biopsy: This is done by making a wedge-shaped incision that begins 2 to 3 mm from normal tissue and penetrates the region surrounding abnormal tissue.
  Tissue should always be incised narrow and deep.

Excision Biopsy

• This procedure should be done for the small lesions which are clinically benign.
• In this, the complete lesion should be removed for examination and diagnosis. So it is both diagnostic and curative.

Trucut Biopsy

It is done using a specialized device wherein a gun with a true cut tip is inserted into the surface tissue/organ and the gun is fired to close the punching needle to catch and cut the adequate tissue.
It is done in prostate, breast, and surface tumors.

FNAC

• This is the cytological study of tumor cells to find out the disease and also confirm whether it is malignant or not.
• It is done by using 23 or 24-gauge needles fitted to specialized syringes which create negative pressure for aspiration and contents are smeared on slides.
• It is contraindicated in testicular tumor.

Frozen Section Biopsy

• It is done when a biopsy report is needed at the earliest.
• It is done in the pathology set-up existing adjacent to the operation theater.
• In this an unfied fresh tissue is frozen (using carbon dioxide) in a metal and sections are made and stained.
• The advantage of this technique is that it is quick and the surgeon can decide further steps in surgery.

Ultrasound-guided or CT-guided

• This procedure is conducted with a large needle with assisted CT scan equipment.
• Simultaneous CTscanallowidentifiationand visualization of the exact size of the tumor on a computer screen.
• It enables the operator to guide the needle into the tumor and obtain several samples of tissue.
• Tissues were then later examined by a histopathologist.

Brush Biopsy

• In this, a brush biopsy kit is supplied by the manufacturer which consists of a brush biopsy instrument, bar-coded glass slide, alcohol-based fixative and protective plastic case for mailing, and instruction sheet.
• In this, the nylon brush is designed to collect cells from all layers of epithelium including the basal cell layer of epithelium.
• The procedure includes the application of firm pressure on the lesion rotating brush 5–10 times.
  After this nylon brush is manipulated on a glass slide so more cells are spread over the slide.
• The slide is analyzed by a computer program designed for pathological review.
• Results are interpreted as negative, positive, or typical.