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    • Indications for ascending urethrography
      • Stricture
      • Urethral trauma
      • Fistulae or false passage
      • Congenital abnormalities
    • Contraindications to ascending urethrography
      • Acute urinary tract infection
      • Recent instrumentation
    • LOCM
      200–300 mg I mL−1 20 mL. Prewarming the contrast medium will help reduce the incidence of spasm of the external sphincter.
    • Equipment required
      • Fluoroscopy unit and spot film device
      • Foley catheter 8-F
    • Consent is required
    • Ascending urethrography procedure
      1. Patient supine
      2. The catheter is connected to a 50 mL syringe containing contrast medium and flushed to eliminate air bubbles
      3. Using aseptic technique, the tip of the catheter is inserted so that the balloon lies in the fossa navicularis (i.e. immediately proximal to the meatus within the glans), and its balloon is inflated with 2–3 mL of water to anchor the catheter and occlude the meatus
      4. Contrast medium is injected under fluoroscopic control, and steep (30–45°) oblique films are taken
      5. Gentle traction on the catheter is used to straighten the penis over the ipsilateral leg and prevent urethral overlap or foreshortening from obscuring pathology
    • Ascending urethrography may be followed by descending micturating cystourethrography to demonstrate the proximal urethra and bladder, assuming there is no contraindication to bladder catheterization
    • It may be possible to fill the bladder retrogradely via the urethral catheter if the patient is able to relax the bladder neck (and thus avoid bladder catheterization)
    • Complications of ascending urethrography
      • Acute urinary tract infection
      • Urethral trauma
      • Intravasation of contrast medium, especially if excessive pressure is used to overcome a stricture
    • Indications for retrograde pyelography
      • Demonstration of the site and nature of an obstructive lesion
      • Demonstration of the pelvicalyceal system and potential urothelial abnormalities after previous indeterminate imaging
    • Contraindication to retrograde pyelography is acute urinary tract infection
    • HOCM or LOCM
      150–200 mg I mL−1 (i.e. not too dense to obscure small lesions) 10 mL
    • Fluoroscopy unit is required
    • Consent is required as for surgery
    • Retrograde pyelography procedure in the operating theatre

      1. The surgeon catheterizes the ureter via a cystoscope and advances the ureteric catheter to the desired level
      2. Contrast medium is injected under fluoroscopic control and spot films are exposed
      3. Some form of hard copy or soft copy recording is recommended—ideally to the hospital PACS (picture archiving and communication system)
    • Retrograde pyelography procedure in the x-ray department

      1. With ureteric catheter(s) in situ, the patient is transferred from the operating theatre to the x-ray department
      2. Urine is aspirated, and under fluoroscopic control, contrast medium is slowly injected
      3. Care should be taken to eliminate air bubbles before injection (as these may mimic pathology such as tumour or calculus)
      4. About 3–5 mL is usually enough to fill the pelvis, but if the patient complains of pain or fullness in the loin, the injection should be terminated before this
      5. Images are taken as the catheter is withdrawn. These should include frontal and oblique projections
    • Postprocedure care

      • Postanaesthetic observations
      • Prophylactic antibiotics may be used
    • Complications of retrograde pyelography
      • Pyelosinus extravasation and pyelotubular reflux due to overfilling may result in pain, fever and rigors
      • Introduction of infection
      • Damage or perforation of the ureters or renal pelvis
    • What is the preferred technique for all spinal pathology?
      Magnetic resonance imaging (MRI)
    • Why is MRI considered the only technique that directly images the spinal cord and nerve roots?

      Because it provides detailed images of soft tissues without using ionizing radiation
    • How does MRI with intravenous gadolinium aid in diagnosis?

      It helps in diagnosing spinal infections, tumors, and postoperative assessments
    • What does CT provide in terms of spinal imaging?

      Optimal detail of vertebral structures
    • In what situations is CT particularly useful?

      In spinal trauma, spondylolysis, and vertebral tumors
    • What are plain films useful for?
      Suspected spinal trauma and spinal deformity
    • What is the use of ultrasound in spinal imaging?

      It is useful in the infant spine
    • What is arteriography used for in spinal imaging?

      Further study of vascular malformations
    • What is radionuclide imaging primarily performed for?

      Suspected vertebral metastases
    • What are the advantages of MRI over other modalities of imaging the spine?

      • Noninvasive
      • Uses multiple imaging planes and sequences
      • Uses non-ionizing radiation
      • Better contrast resolution for soft tissue
    • What are some indications for MRI of the lumbar spine?

      Bulging disc, spondylosis, discitis, trauma, tumors, congenital abnormalities, post-operative spine
    • What are the most common contraindications for MRI examination?

      Electrically, magnetically or mechanically activated implants, intracranial aneurysm clips, ferromagnetic surgical clips, metallic foreign body in the eye, metal shrapnel or bullet
    • What are the steps for patient preparation before an MRI?

      1. Explain the procedure to the patient
      2. Instruct the patient to keep still
      3. Note the weight of the patient
      4. Ask the patient to undress and change into a hospital gown
      5. Remove all metal objects
      6. Check renal function tests before gadolinium administration
      7. Accompany claustrophobic patients
      8. Offer earplugs or headphones
    • Why are metal and electronic items not allowed in the MRI exam room?

      They can interfere with the magnetic field of the MRI unit
    • What items are specifically mentioned as not allowed in the MRI exam room?

      Watches, hearing aids, pins, hairpins, metal zippers, jewelry, removable dental work, eyeglasses, mobile phones
    • Where does the cauda equina exist within the lumbar spine?

      It exists within the lumbar cistern
    • At what level does the spinal cord terminate?

      At level L1/L2
    • Why is lumbar puncture performed at levels L3/L4 or L4/L5?

      To avoid accidental injury to the spinal cord
    • What is an intervertebral disc?
      It lies between adjacent vertebrae in the vertebral column
    • What are the functions of an intervertebral disc?

      • Allows slight movement of the vertebrae
      • Acts as a ligament to hold the vertebrae together
      • Functions as a shock absorber for the spine
    • What are the components of an intervertebral disc?

      The annulus fibrosus and the nucleus pulposus
    • What is the composition of the annulus fibrosus?

      It is a fibrocartilaginous tissue
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