Editing Prostate Biopsy (section)

=== Equipment ===

* '''Ultrasound machine and biplanar probe'''
**Probe may be configured as side-fire vs. end-fire
***Randomized trials found no significant difference in prostate cancer detection rates between these two approaches[https://pubmed.ncbi.nlm.nih.gov/24725491/]
**'''The best visualization of the biopsy/needle path is in the sagittal plane'''
**Transperineal biopsy cannot be done with an end-fire probe or a side-fire probe with a short linear array[https://pubmed.ncbi.nlm.nih.gov/29409845/]
***Linear array needs to be long enough to visualize from just beyond the perineal skin to the apex of the prostate
* Disposable sheaths to cover the TRUS probes (e.g. condom)
**See [https://www.youtube.com/watch?v=izurJz0qXF4 Video] on preparing TRUS probe with lubrication and condom
*'''18-guage biopsy instrument'''
**The biopsy instrument advances the needle ≈0.5 cm and samples the subsequent ≈1.5 cm of tissue with the tip extending ≈0.5 cm beyond the area sampled. 
***Throw length/penetration depth/stroke length is the total distance the needle travels
***Notch length is the length of the tissue sample
***See Figure 1 in [https://pubmed.ncbi.nlm.nih.gov/30021242/ link]
***Bard Magnum has notch length of 19 mm and stroke length of 22 mm[https://pubmed.ncbi.nlm.nih.gov/30021242/]
**Therefore, when sampling the PZ, the needle tip may be placed 0.5 cm posterior to the prostate capsule before firing; advancing the needle to or through the capsule can result in sampling of more anterior tissue, missing the most common location of cancers.[https://www.us.elsevierhealth.com/campbell-walsh-wein-urology-9780323546423.html]
* '''Local anesthetic'''
**'''1% lidocaine without epinephrine'''
***'''Maximum safe dose: 3mg/kg[https://tam.nhsh.scot/formularies/highland-formulary/anaesthesia/local-anaesthesia/local-anaesthesia/]'''
****Maximum safe dose with epinephrine: 7mg/kg[https://tam.nhsh.scot/formularies/highland-formulary/anaesthesia/local-anaesthesia/local-anaesthesia/]
***1% lidocaine: contains 10 mg of lidocaine per 1 mL
***Maximum anesthetic volume in mL = maximum allowable dose (mg/kg) x (weight in kg/10) x (1/concentration of local anesthetic) = mL
****In 70 kg patient, can give 3 * 70/10 * 1/1 = 21 mL
***'''5 ml per side, is sufficient to provide pain relief[https://pubmed.ncbi.nlm.nih.gov/24725491/]'''
**1% lidocaine without epinephrine mixed with 8.4% sodium bicarbonate[https://pubmed.ncbi.nlm.nih.gov/34048827/]
***Can use up to 20-30cc
* 7 inch 22-guage spinal needle
*10cc syringe
*Ultrasound-specific lubricating gel
*Specimen containers
*Transperineal only
**PrecisionPoint Transperineal Access System
***Comprised of 3 components[https://pubmed.ncbi.nlm.nih.gov/29409845/]
****Clamp/rail subassembly
*****Distal portions of the rails are used to stabilize the assemble against the perineal skin
****Needle carriage with 4 apertures
****15 gauge access needle
*Prepare equipment
**Apply ultrasound-specific lubricating gel inside disposable sheath (e.g. condom)
**Insert probe into disposable sheath
**Apply constriction method so that lubrication jelly stays at tip of probe
**Apply ultrasound-specific lubricating gel over disposable sheath at tip of probe
**For transperineal only
***Assemble PrecisionPoint Transperineal Access System
****Apply Coban Self-Adherent Wrap to probe
****Put sliding carriage with ring over Coban
*****Stop on sliding carriage towards patient
*****Smaller holes of access canula towards patient
****Tighten ring so that sliding carriage aligned at 12 o'clock on ultrasound probe
**Prepare biopsy instrument