Phillip Bozzini, a German army surgeon, invented the first instrument to visualize the inside of a human body in 1806. He named this device the Lichtleiter. A candle and angled mirrors within the device would enable a surgeon to see inside a body cavity. The device was originally intended to view the pharynx, but it was quickly adapted to view inside the penis and urethra. This was the catalyst for further experimentation and innovation of endoscopic instruments. Maximilian Carl-Friedrich Nitze and Joseph Leiter developed the first true working cystoscope in 1878. From that point on, there has been constant innovation and development that has led to the instruments urologists use today.
Cystourethroscopy is one of the most common procedures performed by a urologic surgeon. It allows for direct visualization of the urethra, urethral sphincter, prostate, bladder and ureteral orifices. There are various indications to perform cystoscopy, and it can be performed as a simple office procedure or as a procedure in the operating room with the patient under general anesthesia. There are both flexible and rigid cystoscopes and a variety of tools that can be incorporated during cystoscopy depending on the situation. Cystoscopy is mostly a diagnostic procedure, but there are a limited number of therapeutic procedures that can also be performed. Below, we will discuss the general anatomy of the urethra and bladder, indications for cystoscopy, contraindications, equipment that can be used, technique and potential complications of cystoscopy.
The first structure encountered during cystourethroscopy is the urethra. In the male, the urethra is divided into segments: the bladder neck or pre-prostatic urethra, prostatic urethra, membranous urethra, and penile urethra which can be subdivided into the bulbous urethra, pendulous urethra, and fossa navicularis. The verumontanum protrudes from the posterior wall of the prostatic urethra just proximal to the external urethral sphincter and contains openings for the prostatic utricle at the apex and ejaculatory ducts on both sides of the very. The female urethra is an approximately 4 cm complex tubular structure that connects the bladder to the external meatus. It is not divided into sections due to its smaller size.
Proximal to the prostatic urethra is the bladder neck (internal sphincter), and then the cystoscope enters the bladder. On entering the bladder, tilting the scope down will reveal the trigone, which is a triangular portion of the bladder floor bordered by the internal urethral opening and the right and left ureteral orifices. The superior portion of the trigone is a raised area named the interureteric ridge which courses between the ureteral orifices and can be used as a landmark to find these openings. The intravesical ureteral orifices are approximately 2 to 3 cm apart.
There are many indications for office-based cystourethroscopy. Most office cystoscopy is performed for diagnostic purposes. One of the most common reasons for a patient to be referred to a urologist is the presence of hematuria, gross or microscopic. Gross hematuria is defined as blood in the urine that can be seen with the naked eye. Microscopic hematuria is defined as 3 or greater red blood cells per high-powered field. Another common indication for regular cystoscopy is any history of malignancy including urethral, bladder, or upper tract UCC. This is often done on a surveillance basis with intervals depending on the type of cancer. Lower urinary tract symptoms (LUTS) are another indication for cystourethroscopy. These symptoms can include obstructive voiding symptoms, irritative voiding symptoms, urinary incontinence, chronic pelvic pain syndrome or recurrent UTIs. Any trauma in which there is a concern for injury to the lower urinary tract necessitates cystourethroscopy, as well as any bladder abnormalities discovered during imaging studies. Removal of foreign bodies, for example, if a patient has an indwelling urinary stent that requires removal, hematospermia, azoospermia or concern for a bladder or lower urinary tract fistula are also reasons for cystourethroscopy.
Rigid cystoscopy in the operating room is indicated for more therapeutic indications. In this setting, it is possible to have fluoroscopy and perform retrograde pyelography. There is also the ability to use multiple additional instruments including resectoscopes to perform procedures such as transurethral resection of bladder tumors, transurethral resection of the prostate, direct vision internal urethrotomy, injection of Botox into the detrusor muscle, and numerous other interventions. Further discussion of these different procedures is beyond the scope of this article.
Contraindications to cystoscopy are relatively straightforward. If there is any evidence of acute urinary infection, the procedure would be contraindicated as it could put the patient at risk for developing sepsis from a urinary source. For this reason, it is recommended to obtain a urinalysis 5 to 7 days before any scheduled cystoscopy procedure. If a UTI is identified, the patient should be treated appropriately prior to the procedure. A contraindication for flexible cystoscopy in the office would be any intolerance to pain or discomfort with the procedure. This may necessitate a trip to the operating room (OR) for cystoscopy under anesthesia. A urethral stricture can sometimes make cystoscopy impossible, as the scope will not be able to pass.
Cystoscopes come in both flexible and rigid options. They are manufactured in a variety of sizes expressed in French (Fr) gauge. A 1 French instrument has a circumference of one-third of a millimeter. Rigid cystoscopes use the Hopkins rod-lens optical system which has the advantage of providing improved optical clarity when compared with the fiberoptic bundles used in flexible cystoscopes. However, this is becoming less noticeable with the adoption of flexible digital cystoscopes. Visualization is also enhanced in the rigid model due to greater irrigant flow rate. Rigid scopes also have larger working channels which allow for a wider variety of instruments that can be used with them. The advantage of the flexible scopes is that they are smaller in size and provide greater patient comfort, which is why they are used for routine flexible cystourethroscopy in the office setting. The flexible endoscope can also be passed easily with a patient in the supine position; whereas, in rigid cystoscopy, the patient must be in the frog-leg or lithotomy position. Another excellent advantage is the movement of the tip of the flexible cystoscope which allows for easier inspection of the bladder and negotiating around an elevated bladder neck or large median lobe of the prostate. With a rigid cystoscope, it is necessary to use multiple lenses with varying degrees of angle to achieve proper inspection of the entire bladder.
Rigid cystoscopes are produced in sets that consist of an optical lens, bridge, sheath, and obturator. These configurations are different depending on the vendor. Vendors that produce these sets include Karl Storz, Olympus, Gyrus/ACMI, and Wolf.
The optical lenses come with tip angles that range from 0 to 120 degrees. The most common lens degrees used during a typical rigid cystourethroscopy include the 30-degree lens and the 70-degree lens. The urethra is best visualized using the 0 to 12-degree lens. A 30-degree lens is most often used for therapeutic purposes. The 70 or 120-degree lens are often required to inspect the anterior and inferolateral walls, dome, and neck of the bladder.
The bridge connects the optical lens to the sheath. There are varying types of bridges. A diagnostic bridge has no working channels. Bridges used for therapeutic cases can have 1 to 2 working channels. An Albarran bridge is a specialized bridge that contains a lever that can deflect wires and catheters that pass through the working channel to facilitate ureteral orifice cannulation. This can sometimes be required in patients that have elevated bladder necks or large median lobes of the prostate. It can also be helpful when attempting to cannulate a transplant ureter or ureters entering the bladder at odd locations.
The cystourethroscopy sheaths come in a variety of sizes. Sheaths can range in size from 15/17 Fr to 25 Fr. Smaller sheaths are ideal for diagnostic cystoscopy and cause less trauma. Larger sheaths are used for therapeutic procedures as they allow more irrigant flow and larger working channels for instruments. Each sheath has an obturator that blunts the distal end of the sheath for passage into the bladder without visual assistance. Blind endoscope passage is generally only recommended to be performed in a female.
Flexible cystoscopes range between 16 and 17 Fr. There are differences in all models with regard to their dip deflection, the direction of view, the field of view, working channel size, illumination and optics. Vendors that manufacture these scopes include Karl Storz, Olympus, and Wolf. Most models provide a field of view approximately 120 degrees and do not have an offset lens. Tip deflection ranges between 120 to 210 degrees and can either be intuitive (same direction as lever deflection) or counterintuitive (opposite direction of lever deflection). The irrigation and instruments have to pass through the same working channel. This necessitates discontinuing the irrigation to pass a flexible grasper through the scope, for example. However, adaptors have been developed to allow the irrigation to be connected while passing instruments. The amount of irrigation is significantly decreased with the instrument passing through the channel. Photodynamic and narrow-band imaging capabilities are available in some models.
Both Karl Storz and Olympus produce fiberoptic and digital models. Digital scopes are now available in high definition (1920 x 1080 pixels) and standard definition (720 x 480 pixels). These scopes do not require focusing or white balancing. Studies have been performed to compare the resolution, contrast evaluation, depth of field, color representation and illumination of fiberoptic, standard and high-definition flexible cystoscopes. One study demonstrated that the high definition scope had significantly higher resolution and depth of field, with slightly improved color representation and no difference in contrast evaluation. Illumination was significantly better in the fiberoptic models when compared to digital. A randomized study performed by Okhunov et al. in 2009 compared optics, performance, and durability of fiberoptic and standard definition digital scopes. This showed a trend of surgeon optical ranking in favor of digital scopes. There was no difference in durability between models.
Irrigant material depends on the situation, but sterile water or normal saline is most commonly used. Nonionic irrigants (water, glycine, sorbitol) are required when using monopolar electrocautery. Isotonic irrigating fluids (normal saline/lactated ringers) can be used when using bipolar electrocautery instruments. This offers the advantage of eliminating the risk of electrolyte disturbance from systemic uptakes, such as Transurethral Resection of the Prostate (TURP) syndrome. Sterile water should be used when bladder samples are collected for cytologic evaluation.
The personnel required for cystoscopy depends on if it is being performed in the office or the operating room. A simple office cystoscopy requires minimal personnel as there is no anesthesia. It is beneficial to have a nurse as an assistant, especially if doing procedures that can be performed more smoothly with an extra set of hands. For example, if performing a cystoscopy to remove an indwelling ureteral stent, it can be beneficial for the surgeon to operate the cystoscope and have his/her assistant operate the flexible grasper. This is not necessary, however. When performing cystoscopy in the operating room, it is necessary to have anesthesia staff as well as circulating nurses and possibly scrub techs for assistance.
Informed consent must be obtained before the procedure. A urinalysis and urine culture is commonly performed before cystoscopy. The AUA best practice policy statement on antimicrobial prophylaxis does not recommend antibiotic administration for routine diagnostic cystoscopy in the absence of patient-related risk factors. The risk factors that require antimicrobial prophylaxis include:
Prophylaxis lasting less than 24 hours with either a fluoroquinolone or trimethoprim-sulfamethoxazole is recommended for therapeutic procedures. Two-line alternatives include an aminoglycoside with or without ampicillin, a first or second-generation cephalosporin, or amoxicillin/clavulanate.
Prior to the procedure, the skin should be prepared with an antiseptic agent. Both chlorhexidine gluconate and alcohol-based solutions can be damaging to mucous membranes and are therefore not recommended for use on the genitalia. Aqueous-based iodophor-containing products such as Betadine are safe on all skin surfaces and are most commonly used for preparation.
After application of the antiseptic agent, a lubricating gel is injected into the urethra. A plain or lidocaine gel may be used. One meta-analysis of four randomized trials found that patients who received lidocaine gel were 1.7 times less likely to experience moderate to severe pain during the procedure.
Before inserting the cystourethroscopy, the external genitalia is inspected for any lesions or anatomic abnormalities. In women, rigid cystourethroscopy insertion can be implemented using a sheath obturator. The scope will need to be directed anteriorly as it is advanced into the bladder. A flexible scope can be inserted similarly as a Foley catheter, with active deflection being used as needed.
In men, the penis is placed on the maximal stretch to straighten the urethra. When a rigid scope is passed, the penis is grasped with 5 fingers of the surgeon’s non-dominant hand. When a flexible scope is passed, the penis is pinched between the third and fourth digits of the non-dominant hand, allowing the thumb and index finger to be free to help guide the scope into the urethra. The penis should be angled 45 to 90 degrees relative to the abdominal wall as the scope passes through the anterior urethra. Once beyond the membranous urethra, the scope is directed anteriorly to enter the bladder. This is accomplished with active upward flexion when using the flexible scope and by dropping the distal end of the scope toward the operative table when using a rigid scope.
The lower urinary tract is systematically evaluated as the scope is advanced, with maximal irrigation running. The penile and bulbar urethra should be evaluated for any sign of stricture. The patient should be encouraged to relax when the scope is advanced through the membranous urethra. Once the scope is in the prostatic urethra, the verumontanum and utricle can be identified posteriorly. The size of the prostatic lobe, length of the prostatic urethra and presence of a median lobe or bladder neck obstruction should be noted.
Upon entering the bladder, the mucosa should be carefully inspected. When using a rigid cystoscope, generally a 30-degree scope is used initially to inspect as much of the bladder as can be visualized. The floor and trigone of the bladder are initially inspected, with the identification of the ureteral orifices, noting their location and number. Efflux from each ureter should be observed for the presence of blood. The remainder of the bladder should be inspected for bladder stones, trabeculation, bladder diverticula, erythematous patches or papillary/sessile bladder lesions. The surgeon can visualize the lateral walls by rotating the cystoscope and keeping the camera orientation fixed. The dome and posterolateral walls of the bladder are inspected using a 70 or 120-degree lens on a rigid scope, or by retroflection on a flexible scope. Prior to removing the scope, the bladder should be drained.
Complications of cystoscopy are generally minor and may include urinary tract infection, hematuria, dysuria and injury to the bladder or urethra. Development of an iatrogenic urethral stricture is a known possible complication of instrumentation.
Cystoscopy is one of the most important diagnostic tools used by a urologist. It is relatively simple and can be performed in a urology office in most cases. It provides a means of diagnosis for numerous urologic conditions and can also be therapeutic when needed. Every urologist should be able to perform this simple procedure as a part of their practice.