What is a cystoscope?

What is a Cystoscope?

A cystoscope is a medical endoscope—a thin, tube-like instrument equipped with a lens system and light source—that is inserted through the urethra to directly visualize the interior of the bladder, urethra, and ureteral orifices. 1, 2

Types of Cystoscopes

There are two main types of cystoscopes used in clinical practice:

Rigid Cystoscope

• Traditional design using a rod lens system developed in the 1960s 3
• Typically 4mm in diameter with fixed optics 3
• Requires more formal positioning and patient preparation 4
• Provides excellent image quality with rigid-lens systems 4

Flexible Cystoscope

• Modern fiberoptic or digital technology first applied to cystoscopy in 1973, with widespread adoption since 1982 4
• Outer sheath of 16F or less with working channels ≥6F for instrumentation 5
• Features 180-degree two-way thumb-directed deflection for superior maneuverability 5
• Causes significantly less pain and fewer post-procedure symptoms compared to rigid cystoscopy 1
• Simplified patient positioning (supine or frog-leg supine) with reduced procedure time 1, 6
• At least equivalent diagnostic accuracy to rigid cystoscopy, and may be superior for visualizing certain lesions, particularly at the anterior bladder neck 1, 2

Clinical Capabilities

Cystoscopy provides complete visualization of:

• The bladder mucosa (entire inner lining) 1, 2
• The urethra (urinary channel) 1, 2
• The ureteral orifices (openings where ureters enter the bladder) 1, 2

Diagnostic accuracy for bladder cancer detection:

• Sensitivity: 87-100% 1, 2
• Specificity: 64-100% 1, 2
• Positive predictive value: 79-98% 1
• Negative predictive value: 98-100% 1

Procedure Details

Initial diagnostic cystoscopy can be performed:

• Under local anesthesia in an office setting 1, 2
• With minimal or no anesthesia for flexible cystoscopy 4
• In a variety of patient positions depending on the type of cystoscope used 4

The procedure involves:

• Inserting the endoscope through the urethra 7
• Using irrigant (sterile fluid) to distend the bladder for better visualization 6
• Systematic examination of all bladder surfaces, the urethra, and ureteral orifices 6

Therapeutic Applications

Beyond diagnosis, cystoscopes can be used for:

• Ureteral stent placement under direct vision 5
• Treatment of urethral strictures and bladder neck contractures 5
• Removal of foreign bodies and ureteral stents 5
• Laser treatment of small bladder tumors 5
• Bladder stone fragmentation 5

Limitations

Important constraints of cystoscopy include:

• Cannot visualize the upper urinary tract (ureters and kidneys beyond the ureteral orifices) 7
• Cannot assess extravesical extension of bladder tumors or lymph node involvement 7
• Limited effectiveness in patients with active bleeding or blood clots in the bladder 4
• Invasive nature with potential complications including urinary tract infection, bleeding, bladder perforation, scar tissue formation, and urinary retention 1, 2

Modern Advances

Recent technological developments include:

• Enhanced cystoscopic modalities such as fluorescence/photodynamic cystoscopy, narrow band imaging, and confocal laser endomicroscopy 1
• Wireless cystoscope systems with 4K ultra-HD cameras and portable LED light sources 3
• Flexible videocystoscopes for both diagnostic and therapeutic procedures 4
• Miniaturized laser probes (300-600 microns) for therapeutic applications 8