Cystoscopy

Cystoscopy, also called cysturethroscopy, is a procedure where a cystoscope (an endoscope) is inserted into the urethra to examine the urethra, urethral sphincter, prostate, urinary bladder, and uretral orifices. Fluid is continously irrigated into the bladder to prevent it from collapsing and reducing view. The endoscope can visualise the organs, take biopsy samples, and perform a limited number of therapeutic interventions like cauterisation. It's one of the most common procedures performed in urology.

Indications

• Haematuria
• Suspicion of tumour
• Urinary obstruction
• Recurrent UTIs
• Urinary incontinence
• Bladder biopsy
• Placement of DJ stent

Types

• Flexible cystoscope
  • Takes on the shape of the urethra -> more comfortable, less pain
  • Does not allow for therapeutic intervention or deeper biopsies
• Rigid cystoscope
  • Is not flexible and therefore more painful to use, especially for men
  • Allows for therapeutic intervention and deeper biopsies
  • Must be performed under general or spinal anaesthesia

Contraindications

• Acute urethritis, prostatitis, epididymitis
• Febrile UTI

Performing cystoscopy on a patient with urinary infection may lead to sepsis.

Technique

• Disinfection of urethral area
• Application of lidocaine gel
• Prepare conductive or non-conductive irrigation fluid
• Insert the cystourethroscope
• Inspect all parts of the urethra, bladder, and ureteral orifices

Enhanced imaging

Not all bladder tumours are easily visible with the naked eye using a cystoscope (called white light cystoscopy), especially carcinomas in situ. Two techniques allow for improved detection of bladder cancer.

Photodynamic diagnosis (PDD), also called fluorescent cystoscopy, is often used, where a fluorescent dye (photosensitiser) called hexyl aminolevulinate (HAL, Hexvix®) is administered into the bladder before the procedure. Cancer cells absorb this dye and glow red or pink when special fluorescent light is shone from the cystoscope, making them easier to see.

Narrow band imaging (NBI) is a similar technique which uses a specific wavelength of light with makes blood vessels more visible. As tumours often are hypervascularised, this can help detect tumours. No photosensitiser is required.

Bladder biopsy

Bladder biopsy is frequently performed in the evaluation of suspected urinary tract malignancy, especially bladder cancer. A urine cytology must be performed beforehand, to look for malignant cells.

If no tumours are visible with "normal" white light cystoscopy but the cytology is positive, one may use photodynamic diagnosis or narrow band imaging to try to detect the tumour. One can also perform a "mapping biopsy", where biopsies are taken blindly from high predilection areas.

A standard technique for tumour biopsy (if the entire tumour cannot be resected) is the method of Bressel:

• 1 sample from tumour
• 1 sample from muscular layer of bladder
  • To look for muscle invasion – important for further treatment
• 4 samples of the sides of the tumor
  • To determine the border of the tumor

Transurethral resection

An instrument called a resectoscope is similar to a cystoscope and can be used to perform transurethral resection of the bladder (TUR-B) or prostate (TUR-P). This is done under spinal or general anaesthesia. The resectoscope has a camera like a cystoscope but is thicker, and has a metallic loop on the end. The metallic loop is a monopolar cautery, which is used to resect the bladder, or the prostate from the inside of the urethra. During TUR one obtains histological samples for pathological examination.

TUR-B is indicated for as a procedure which is both diagnostic and therapeutic for all stages of bladder cancer. TUR-P is indicated for severe benign prostatic hyperplasia instead of prostatectomy. It is not used for prostate cancer.

During TUR-P, the prostate capsule is not removed. The remaining cavity will be epithelialized after a few months.

TUR syndrome

During cystoscopy the bladder is continously irrigated with fluids. During cauterization bleeding and thermal burns occur, which is washed out with fluid. In some cases, a monopolar resectoscope is used because it is cheaper than a bipolar one. To prevent burns, the fluid used to irrigate must be non-conductive, usually distilled ion-free water. Some of this water can be absorbed, causing hypotonicity and potentiallly haemolysis. This usually only occurs after prolonged irrigation, and so TUR is usually kept shorter than 1 hour to reduce the risk.

Nowadays one can use glycine solution (which is also non-conductive but is isotonic) to prevent TUR syndrome, but this fluid is more expensive. One can also use bipolar cautery, as this eliminates the need for non-conductive fluids.