Stones & instrumentation

Urolithiasis

By

Dr. Ahmad A. Al-Sabbagh

Urology Department

Under-graduate courses

• Ten per cent of the population may expect to have an episode of stone disease during their lifetime.

• The upper urinary tract is affected in most cases. Bladder stones are found in a small proportion of men with bladder outflow obstruction.

• The incidence in children remains high in some developing countries.

• The prevalence of stones changes with age and is lower in women, although the male: female ratio is becoming more equal.

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ePIdeMIOlOgy

• Diet

Tomatoes (Oxalate) Livers (Uric Acid) Milk Products (Calcium)

• Metabolic

Ca Stones: Hypercalcemia, Hypercalccuria. Hyperoxaluria

Uric Acid: Gout, Hyperuricosuria

Cystine: Autosomal recessive Disorder

Xanthine Stones: Heriditary xanthinuria

• Infection

Changes the PH of Urine (Urea Splitting Organisms → alkalinization of Urine)

• Obstruction:

Stasis & infection©

eTIOlOgy

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TyPeS Of STOneS

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TyPeS Of STOneS

Calcium Oxalate StonesUric Acid Stone

Cystine Stones Struvite Stone

• Renal stones

Loin pain. The most severe pain occurs when stones are moving,

Asymptomatic stones often are found during radiographic or ultrasound imaging for unrelated reasons

• Ureteric stones

Acute colicky pain, When a ureteric stone has been present for 72 hours, the acute pain subsides and the patient has relatively few symptoms.

Stone Ureter may be impacted in one of the natural ureteric narrowing points (PUJ, when crossed by the common iliac artery, intramural part)

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clInIcal PIcTUre

• Bladder Stones:

Either formed in the bladder (Due to Obstruction) or descending from the upper tract.

Presenting with Frequency, Interruption of urine stream & Maybe terminal hematuria

• Urethral Stones

Mostly Migrating from above, or rarely formed in a urethral diverticulum

Causes interruption of stream then acute retention

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clInIcal PIcTUre

• Infection

• Obstruction

• Migration

• Hematuria

• Retention (if impacted in the urethra or the bladder neck)

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cOMPlIcaTIOnS

• Laboratory:

Urinalysis

Serum Calcium & Uric Acid

Renal Function Tests

• Radiological

KUB – 90% of Stones are Radio-opaque

IVU: Stone appear as filling defect , obstruction & Backpressure

CT Scan : Helpful to diagnose Radiolucent Stones & determining stone density

Ultrasound & Radio-Isotopic Scan

• Instrumental

Endoscopy

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InveSTIgaTIOnS

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InveSTIgaTIOnS

Left Renal Stone

Urinary Bladder Stone

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InveSTIgaTIOnS

Right Upper Ureteric StoneKUB IVP

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Left Renal Stone - Axial Right Renal Stone - Coronal

Right Renal Stone – 3D Reconstructive

Renal Stones:

• Conservative management of small renal stones

• Extracorporeal shockwave lithotripsy

Effective for treating kidney stones 2 cm in maximum diameter, as long as no obstruction to the passage of stone fragments is present.

• Retrograde Renoscopy

A laser fibre can be introduced through a flexible fibre optic reterorenoscope, which is introduced through the urethra and bladder, and up the ureter to the renal collecting system. Stones 1 cm in diameter can be disintegrated.

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Renal Stones:

• Percutaneous nephrolithotomy Stones 2 cm in diameter or more may be treated by percutaneous nephrolithotomy.

Under fluoroscopic control

• Open surgery

Staghorn stones Kidneys that contribute 10% of overall renal function should usually be removed

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Ureteric Stone:

• Conservative management

Most stones 5 mm in maximum diameter are likely to pass spontaneously, with high amounts of fluid intake & Diuretics

• Extracorporeal shockwave lithotripsy

Less successful for ureteric stones than renal stones

• Endoscopic ureterolithotomy

With or without stone disintegration

• Open surgery

In case of ureteric pathology, such as stricture

• Laparoscopy©

TreaTMenT

Endoscopic Uretrolithotomy

Bladder Stones

• Endoscopic (Cystolitholapaxy)

In stones less than 2cm

• Surgical (Cystolithotomy):

Larger than 2cm,

Hard stones (Resistent for Crushing)

Stones associated with diverticulum or Bladder neck obstruction (BPH)

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• Stone analysis

• Serum Ca & Phosphorus to exclude Hyperparathyroidism

• 24 hour collection of urine for: Ca, Oxalate, Citrate, Uric Acid

• Diet modification (Avoid diet containing the causative crystals) plus high fluid intake

• Modifivation of Urine PH (Alkalinization in uric acid stones by oral NaHCO3 or Acidification in phosphate stones by Vitamin C)

• Prevention & Treatment of UTI

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PrevenTIOn & MeTabOlIc WOrk-UP

Instrumentation & EndoscopyBy

Dr. Ahmad Al-Sabbagh

Urology Department

Under-graduate courses

• A basic understanding of lower urinary tract anatomy and availableinstruments is essential for safe and successful manipulation of the lowerurinary tract. This chapter addresses basic techniques that are used in thepractice of urology.

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ObjecTIve

Indications

• Diagnostic

Collection of urine for culture in females for in order to avoid contamination by skin flora. not necessary in males because clean-catch specimens can be obtained

Measurement of the postvoiding residual urine (can be performed less invasively with ultrasonography)

Instillation of contrast agents into the bladder and urethra for cystourethrography

Urodynamic studies to assess bladder and urethral function

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UreThral caTheTerIzaTIOn

Indications

• Therapeutic

Relief of infravesical obstruction is one of the most common therapeutic indications for urethral catheterization (eg. prostatic enlargement)

To drain the bladder after surgical procedures involving the lower urinary tract

Accurately monitor urinary output.

Intermittent catheterization (by the patient or an assistant) is a common means of managing neurogenic bladder dysfunction

Install medications (eg. Intravesical chemotherapy)

Used as stents after surgery to allow healing of an anastomosis involving urethra.

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Types of Catheters

• Straight catheters rubber or latex (Robinson) and polyurethane (Nelaton)

For one-time catheterizations

• Catheters with a curved tip (e.g., coudé catheters)

bypass the male urethra in the presence of prostatic enlargement

• Self-retaining catheters, (Pezzer and Malecot)

the catheter wings maintains the catheter within a hollow viscus.

• Foley-type catheters ,with the balloon mechanism.

Two-way Foley catheters

Three-way catheters they are used when bladder irrigation and drainage are necessary, as, for example, in a patient with bladder hemorrhage

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Notes

Catheter size (Outer diameter) is usually referred to using the French (Fr) scale in which each millimeter in diameter is approximately 3 Fr.

One should choose the smallest urethral catheter that will accomplish the purpose of catheterization.

Catheters made from latex or plastic (polyurethane) are not intended for longtime drainage since theses materials react with urine and result in the formation of "encrustations". Consequently catheters made from inert materials such as Silicone are generally recommended whenever prolonged drainage is needed.

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Preparation

The patient should be informed of the reason for catheterization and what to expect in terms of discomfort.

Sterilize and drape the external genitalia and surrounding area as for a surgical procedure.

Local anesthesia , such as 2% lidocaine hydrochloride jelly is injected

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Technique (Male Patient)

The penis is placed on stretch perpendicular to the body without compressing the urethra.

The catheter is placed in the urethral meatus by holding the catheter at the tip.

Gentle advancement of the catheter is performed

As one approaches the bulbomembranous urethra one can feel the natural resistance of the external sphincter here the patient is asked to take slow, deep breaths to relax and allow easier catheter passage.

If resistance is met, one should not attempt forceful catheter insertion but should apply continuous, gentle pressure and ascertain at what level the potential obstruction exists.

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Technique (Female Patient)

After spreading the labia, one can usually identify the urethral meatus easily, and the catheter is placed gently into the bladder

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Difficult Catheterization

Difficulty in catheterizing the male patient can result from a variety of causes.

Use catheter introducers

Use filliform followers and catheters

If catheterization is difficult /failed / complicated (false passages) the best solution is to divert urine by Percutaneous suprapubic cystostomy or to catheterize the bladder by the use of urethrocystoscopy (flexible or rigid)

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Definition

Direct visualization of the anterior and posterior urethra, bladder neck, and the bladder

Indications

Diagnosis of lower urinary tract disease. (e.g.hematuria, Obstructive & Irritative Voiding Symptoms)

Prior to treatment of many LUT diseases e.g prior to TURP (Transurethral resection of the prostate) or TURBT (Transurethral resection of bladder tumor)

Access to the upper urinary tract for diagnosis and treatment

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cySTOUreThrOScOPy

Equipment

Cystourethroscopy can be performed with either rigid or flexible endoscopes.

Rigid cystourethroscopes consist of a sheath, obturator, bridge, and telescopes.

Constant Fluid irrigation and Illumination to visulalize most hollow viscus in the body and for The bladder several types of irrigant fluid are available (normal saline, distilled water, clycine.

The image from a rigid or flexible endoscope can be transmitted to a TV monitor with the use of a video-camera (video-cystourethroscopy).

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Technique

Position of the patient for rigid urethrocystoscopy: Lithotomy position. For flexible urethrocystoscopy: Supine position

The urethral meatus should be inspected

The sheath of the cystourethroscope is generously lubricated

the endoscope can be passed under direct vision with a 0- to 30-degree lens,

Systematic inspection of the entire urethra and bladder should be performed during cystourethroscopy.

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Applications

• Cystolitholapaxy:

Description: Endoscopic fragmentation of bladder stone and retrieval of the fragments

Instruments used: the standard urethrocystoscope + one of the stone fragmenting instruments: stone crushing forceps (crocodile forceps) or pneumatic, laser lithotriopsy.

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Applications

• Bladder Biopsies

Description: Taking a representative sample from a bladder growth endoscopically by a biopsy forceps. The sampling is done without electric thermal energy.

Instruments used: the standard urethrocystoscope + biopsy forceps (cold cup forceps)+ Bugbee coagulating electrode

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Applications

• TURP (Transurethral resection of the prostate)

Description: Resection of the prostatic adenoma by electric thermal energy. The curenthas two properties it could be cutting current i.e. used to cut the gland into small pieces (chips) or coagulating current i.e. used to coagulate the bleeding spots

Instruments used: the standard urethrocystoscope + the resectoscope sheath+ cutting electrode (loop) + coagulating electrode (ball) + Working element

Remarks: Since electric thermal energy is utilized a non-electrolyte irrigant should be used during TURT e.g. water, glycine, sorbitol. Normal saline can not be used.

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Applications

• Ureteroscopy and related procedures

The ureteric orifice is identinfied

A guide wire is introduced into the ureteric orifice through the whole ureter and up to the kidney

Dilatation of the intramural ureter is performed by serial telescopic dilators or balloon dilator

The ureteroscope is advanced into the ureter under vision and along the guide wire

Once in the ureter the desired endoscopic procedure could be done e.g stone retrieval, stone disintegration, endoureterotomy (cutting a ureteric stricture), taking a biopsy, resecting a tumour…etc.

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Applications

• Nephroscopy and related procedures:

Description: Getting access to the inside of the kidney namely the pelvicalyceal system to conduct a certain procedure. The commonest procedure to be be done via this route is PCNL (percutaneous nephrostolithotomy

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Health & Medicine

Stones & instrumentation