This dissertation, "Endoscopic Totally Extraperitoneal Inguinal Hernioplasty: Techniques and Advances for Optimal Outcome" by Hung, Lau, 劉雄, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled ENDOSCOPIC TOTALLY EXTRAPERITONEAL INGUINAL HERNIOPLASTY: TECHNIQUES AND ADVANCES FOR OPTIMAL OUTCOME Submitted by Hung LAU for the degree of Doctor of Medicine at The University of Hong Kong in March 2006 Inguinal hernia repair, one of the commonest operations since antiquity, embodies the art and science of surgery. Endoscopic totally extraperitoneal inguinal hernioplasty (TEP), first reported in 1992, remains an evolving technique. The aims of this thesis were as follows: 1) to study the retropubic vascular anatomy; 2) to examine the impact of TEP on urodynamic function; 3) to identify predictive factors for postoperative pain and morbidities; 4) to conduct clinical trials to optimize postoperative outcomes; 5) to evaluate the extended applications of TEP. We studied the retropubic vascular anatomy in 121 patients. The overall incidence of 'corona mortis' was 40%. We recommended using the obturator foramen as an anatomical landmark to indicate an adequate inferior dissection of the preperitoneal space for mesh placement. Although TEP involves dissection of the urinary bladder from the pubic bone and the placement of a preperitoneal mesh in direct contact with the bladder, our uroflowmetry study proved that TEP conferred no impact on voiding function. ii Pain is the commonest discomfort experienced by patients while seroma is the most frequent postoperative morbidity. Age and gender were identified to be the most significant predictive factors of pain after TEP. Our randomized trial proved that extraperitoneal instillation of bupivacaine did not bestow any additional analgesic benefits compared to that of wound infiltration. Significant clinical factors associated with seroma formation included old age, large hernial defects and extension of the hernia into scrotum. Our case-control study proved that prosthetic stapling was not necessary in selected patients during unilateral TEP. For bilateral TEP, we conducted a randomized clinical trial to compare biologic versus mechanical fixation of the prosthetic mesh. The use of fibrin sealant for mesh fixation conferred a significant reduction of analgesic consumption but resulted in a higher incidence of seroma formation. Fibrin sealant allows biologic fixation of the mesh onto the pelvic floor without causing injury to underlying structures. In 2001, we extended the application of TEP to become an outpatient service, which proved to be safe and cost-effective. The efficacy and outcomes of needlescopic TEP were comparable to those of conventional TEP. For patients who are medically unfit for general anesthesia and opt for TEP, we demonstrated the feasibility and safety of performing TEP under spinal anesthesia. Regarding long-term outcomes, our survey proved that the prevalence of chronic pain was low. Chronic pain after TEP was mostly mild and transient. In the author's personal experience of more than 1,200 TEPs with a median follow-up exceeding 1 year, recurrence rate was 0.27%. The present thesis addresses retropubic vascular anatomy, pathophysiology of TEP on human body and risk factors for morbidities, which are of fundamental importance to iii enhance functional recovery after TEP. We support biologic fixation of prosthetic mesh and the use of multimodal analgesia. TEP is an essential component of the surgeon's ar