Endoscopic Urology: Diagnostic and Therapeutic Procedures

Classification and Basics of Endoscopic Procedures in Urology

Endoscopic procedures are defined as surgical or diagnostic interventions performed through the body's natural orifices. In the field of urology, the primary access point is the urethra. These procedures are fundamentally categorized into two types: diagnostic and therapeutic. Diagnostic procedures include urethrocystofibroscopy (also commonly referred to as cystoscopy), which allows for the visual inspection of the lower urinary tract. Therapeutic procedures are more invasive and include Transurethral Resection of the Prostate (known as RTUP or TURP) and Transurethral Resection of the Bladder (known as RTUV or TURB). These interventions are essential for treating obstructive or neoplastic conditions within the urinary system without the need for traditional open surgery incisions.

Urethrocystofibroscopy (Cystoscopy): Diagnostic and Ambulatory Procedures

Urethrocystofibroscopy is a diagnostic procedure performed on an ambulatory basis, meaning the patient does not typically require an overnight hospital stay. The primary objective is to allow the surgeon to visualize, in a specific anatomical order, the urethra, the prostate (in male patients), the bladder, and the ureteral orifices (ureteres). The surgical technique begins by placing the patient in the lithotomy position (posición litotómica), utilizing leg holders (pierneros) and stirrups (muescas) for stabilization. The antisepsis process is followed by the placement of surgical drapes (campos), which include large drapes to cover the legs and leg holders, two lateral drapes, one large cephalic drape, and a special drape placed underneath the sacrum, leaving only the perineum exposed for access.

Local anesthesia is typically administered using lidocaine jelly (lidocaina en jalea) delivered via a $20\,ml$ syringe. Once the area is anesthetized, the cystoscope is introduced to evaluate the anatomy of the urethra, prostate, and bladder. If any suspicious lesions are identified during this visual evaluation, a biopsy is performed to obtain tissue for pathological analysis.

Specific Instrumentation and Components of the Cystoscope

The instrumentation required for a diagnostic cystoscopy is specialized and includes several key components. The first instrument used following the administration of lidocaine is the Sheath (camisa), ranging in size from $19\,Fr$ to $22\,Fr$. This is a rigid, tubular structure that passes through the urethra. Inside the sheath, a Mandril (obturator) is always inserted; the mandril has a blunt tip designed specifically to prevent lesioning of the urethral walls during insertion.

Additional components include the endo camera and the optical lens, which typically has a $30^\circ$ angle. A light source, connected via a fiber optic cable, is necessary for visualization. A Bridge (puente) is placed between the sheath and the optic to secure the assembly and ensure the lens does not fall out during the procedure. For tissue collection, flexible biopsy forceps (pinza de biopsia) are used; flexibility is crucial because a rigid instrument would get stuck due to the natural anatomical curvature of the patient's urinary tract. All visual data is displayed on a monitor, which is usually part of a mobile equipment tower. Unlike laparoscopic procedures, an insufflator is not used; instead, to create the necessary space for visualization, the bladder is filled with an irrigation solution such as saline (solución fisiológica) or distilled water (agua destilada). Disposable materials for this procedure include $50\,ml$ and $20\,ml$ syringes, lidocaine jelly, and a V-14 irrigation kit (guÍa de irrigación).

Therapeutic Procedures: Transurethral Resection (TUR)

Transurethral Resection (RTU) involves the excision of tissue through the urethra and is divided into two main types: resection of the prostate and resection of the bladder. Transurethral Resection of the Prostate (RTUP) involves the removal of the prostate gland in small fragments. This is the standard treatment for Benign Prostatic Hyperplasia (HPB), a condition where the prostate enlarges and obstructs urinary flow.

Transurethral Resection of the Bladder (RTUV) involves the excision of vesical (bladder) tissue. During this procedure, the surgeon can safely resect the mucosa, submucosa, and the muscularis layers. However, the serosa, which is the outermost layer of the bladder, cannot be treated via the transurethral route because of the risk of perforation outside the organ. Both procedures rely on the same principle of using a resectoscope to reduce tissue into small fragments that can be easily evacuated from the bladder.

Surgical Instrumentation for Transurethral Resection

The instrumentation for RTU is more complex than that for diagnostic cystoscopy. It utilizes a lens system ranging from $0^\circ$ to $30^\circ$, which is inserted into the resectoscope after the initial mandril has been removed. The standard sheath (camisa) used for these procedures is larger, typically $26\,Fr$, and is accompanied by a mandril. The resectoscope is the central element that houses both the optics and the working loops (aros or anos).

There are specific loops used for different functions: cutting loops (anos de corte) often referred to as "gonchito" and coagulation loops (pelotica), both of which are connected to a monopolar cable. These loops measure approximately $7\,mm$ in length and are introduced through the sheath once the mandril is withdrawn. Another critical instrument is the Toomey syringe, a large-volume glass syringe. It features a metal tip designed to fit perfectly into the sheath and a transparent body that allows the surgical team to visualize the fragments of tissue as they are extracted from the bladder. Disposable materials specific to RTU include lidocaine jelly, a V-109 irrigation kit, and a large-bore hematuric bladder catheter (sonda vesical hematúrica) sized $22-24\,Fr$, along with a collection bag and additional syringes ($10\,ml$ and $20\,ml$).

Comprehensive Surgical Technique for Transurethral Resection (RTU)

The surgical sequence for an RTU begins with the patient in the lithotomy position using leg holders and stirrups. Following antisepsis and draping, lidocaine jelly is inserted into the urethra. The $26\,Fr$ sheath is introduced using its mandril, and the system is connected to a continuous irrigation setup using the V-109 kit. The constant flow of irrigation solution fills the bladder, providing the space needed for the surgeon to see; as the surgeon resects the prostatic adenoma or bladder lesion, the resulting tissue fragments fall to the bottom of the bladder.

Once the resection is complete, the surgeon must extract the fragments. This is done using the Toomey syringe. The surgeon injects fluid into the bladder and then applies pressure; this pressure causes the fragments to "bounce" and surface, at which point the surgeon aspirates the syringe, drawing the small fragments into the transparent body of the syringe. These fragments are then emptied into a specialized surgical apron (delantal) worn by the surgeon across their lap. This apron is shaped like a funnel and contains a filter at the bottom that catches the fragments while allowing the fluid to drain. If such an apron is unavailable, a jar or container with gauze in the middle can be used as an impromptu filter for the fragments.

Fragment Extraction and Postoperative Care

The final stages of the procedure involve meticulous hemostasis control to manage bleeding and a thorough verification to ensure no tissue residue remains in the bladder. Once the surgeon is satisfied with the resection and the clarity of the field, a three-way hematuric Foley catheter ($22-24\,Fr$) is placed. This catheter allows for continuous bladder irrigation (lavado continuo) to prevent blood clots from forming post-surgery. This irrigation is maintained via a V-14 irrigation kit and the fluid is drained into a standard collection bag. This postoperative care is vital to ensure the patency of the urinary tract following the mechanical trauma of the resection fragments and the surgical site healing.