Minimally invasive surgery

Minimally invasive surgeryIn the late 1970s and early 1980s an entirely new attitude began to appear within some branches of surgery which opened the path for minimally invasive surgery.This change is best illustrated in the history of renal stone surgery where the development of percutaneous stone removal at the Institute of Urology in London' and the University of Mainz in Germany' ensured that the trauma of surgical access was reduced to a minimum.New endoscopic instruments were produced giving the urologist an excellent view of the interior of the kidney and thereby decreasing the time spent operating while ensuring that stones could be satisfactorily removed and that postoperative complications were minimized.Eventually, in 1980, the treatment of urinary calculi by extracorporeal shockwave lithotripsy (ESWL) was reported3.This was an entirely new concept whereby an electrical discharge from outside the body could fragment calculi within the urinary tract.This ensured that the physical trauma inflicted upon the patient was reduced to a minimum while achieving a maximum therapeutic result.Although the various methods for treating urinary calculi have never been submitted to a clinical trial, ESWL does seem to be the most satisfactory method of treating stones of 3 cm or less in diameter.In the case of staghorn calculi, a combination of percutaneous debulking and ESWL is preferable.Thus the removal of most renal stones has been transformed from an aggressive, debilitating operation necessitating prolonged hospitalization and convalescence to an out-patient procedure.Minimally invasive procedures may be carried out through natural tracks or tracks prepared by the interventional radiologist or surgeon.A philosophical leap was required in the acceptance of prepared tracks for minimally invasive surgery, but such procedures have now been performed for many years.For example, Wittmoser introduced transthoracic endoscopic sympathectomy in the 1950s4, Burhenne has extracted residual stones percutaneously from the common bile duct through the T tube tract since 19725, and Fernstrom carried out the first percutaneous removal of a renal stone in 19766.In spite of this, it is interesting that some surgeons initially preferred open renal stone removal through a lumbotomy incision, and mini-cholecystlithotomy through a small abdominal incision, to the less invasive and technically easier percutaneous procedures.Percutaneous endoscopic resection of upper urinary tract transitional cell tumours has been performed7, and how far away are we from percutaneous aspiration of a renal cell carcinoma following ultrasonic destruction of the tumour with the Cavitron (C.U.S.A.:@, Valleylab, London, UK)Arthroscopy is now accepted as the method of choice for the management of tears of the menisci in the knee.It has also been used to examine many joints, including the wrist, elbow, shoulder and ankle.Percutaneous discectomy is currently under evaluation and appears to be extremely useful in selected cases.It is surely not beyond the bounds of possibility that, in future, percutaneous hip replacement may be performed.Great interest has also been shown in the fragmentation of gallstones by ESWL8.The results have been encouraging, but the technique is limited by the requirement that the gallbladder must be functioning and that best results are obtained if ESWL is followed by prolonged administration of bile acids.Percutaneous cholecystlithotomy and ch~lecystlithotripsy~ have been suggested as an adjunct to ESWL, but they may also be performed as independent procedures with a high success rate and a low incidence of complications.Dubois and colleagues' have performed 250 laparoscopic cholecystectomies with excellent results and in some cases this may be performed as a day case under local anaesthesia.Under laparoscopic vision, the view of the gallbladder is exactly the same as if the abdomen were laid open before the operating surgeon.Through two separate stab incisions other instruments are introduced.The approach to the cystic duct and cystic artery is magnified, and the gallbladder can be dissected from the liver with endoscissors and diathermy.A cannula can be inserted into the common bile duct to perform a cholangiogram; if a stone is seen a flexible ureteroscope may be inserted through the cystic duct stump and the stone broken up under direct vision using the laser.