In  the last 4 years all the different types of abdominal procedures of general surgery have been performed by MIS, even in paediatric patients and pregnant women; it seems to me that in this period of time the most skilled laparoscopic surgeons have been trying to demonstrate that, whatever had been performed before by open surgery, even the most complicated procedures such as a pancreatectomy or a liver resection, could be replicated by laparoscopy. I strongly believe that in certain of these instances the focus of this challenge might not have represented the patients' best interest. I therefore think that this review should be limited to those areas where the results achieved by MIS are more rewarding or challenging or even still unsolved, such as the management of stones of the biliary tract, treatment of pathology of the gastroesophageal junction, oncologic surgery, treatment of benign lesions of solid organs, surgery of obesity, outpatient laparoscopic surgery and, finally, the role of laparoscopy in emergency patients.  

Gallbladder and the biliary tract 

While laparoscopic cholecistectomy (LC) is today the procedure of choice in the management of patients with gallbladder stones, the issue of identifying and treating patients with associated common bile duct (CBD) calculi is still debated. Preoperative endoscopic retrograde cholangiopancreatography (ERCP) in all patients with clinical, ultrasound (US), or laboratory suspicion of CBD stones is unacceptable because of the large number of negative findings, up to 50% of cases.  Routine use of cholangiography during LC seems more appropriate; when in doubt, choledochoscopy and/or intraoperative US can also be performed. 
When LC came into use, endoscopic sphincterotomy (ES) was the preferred method of management of ductal calculi, on the basis of the reported 85-90% success rate of ES in obtaining complete stone clearance with only about 4% morbidity. Therefore, when CBD stones were identified prior to surgery, treatment by sequential ES and LC seemed the logical approach. Confidence acquired with intraoperative cholangiography, choledochoscopy and US inspired some authors to address  the issue of removing calculi from CBD during the same laparoscopic operation (“one step procedure”). A host of different techniques have been described where by stone extraction can be achieved  by operating a Dormia basket under fluoroscopic or direct choledochoscopic control. Alternatively, a transcystic route or, in the presence of dilated CBD, a choledochotomy may be used. To avoid the pitfalls of laparoscopic suturing of the CBD, ultrathin choledochoscopes have become available. Balloon dilatation of the cystic duct to facilitate insertion of choledochoscopes has also been described .With all this new and sophisticated technology in place, perlaparoscopic CBD clearance can be obtained in up to 77% of cases; only proximal stones, in the hepatic ducts of the intrahepatic biliary tract, are not with the scope of intraoperative choledochoscopy. A recent European Association for Endoscopic Surgery (EAES) multicentre trial on 212 patients compared sequential ES-LC and one-step laparoscopic treatment of associated ductal and gallbladder stones. Similar success and complication rates could be demonstrated for the two methods, whereas the single-stage approach required a shorter hospital stay; therefore, another apparently well established axiom, i.e. the superiority of ES to surgical CBD exploration, has been disputed by MIS.  
Moreover, transcystic stone extraction turned out to be superior to choledochotomy in terms of morbidity and length of hospitalization. In fact, quite often the positioning of a T-tube or of at a transcystic drainage is necessary following the latter approach; these drainages are left in place for a few weeks, resulting in far greater distress for the  patient than MIS. 
Croce et al. reported no complications in a series of 50 consecutive choledochotomies without drainage.  
Nonetheless, since in this developing field there is still no best way to do things, in some other institutions “one-step” treatment of associated calculi is obtained by performing ES during LC.  
It is essential to collaborate with an endoscopist in the operating room (O.R.) so that if ductal stones identified during LC cannot surgically be removed because of technical/anatomical problems or a lack of expertise, intraoperative ES can spare the patient an uncomfortable postoperative procedure. Questions regarding the ease and safety of cannulating the papilla with the patient in the supine position have been alleged with the realization that there are no additional difficulties and that the technique may even be easier; in fact, the patient is given a general anaesthetic, something rarely encountered in everyday practice of biliary tract endoscopy.  
If possible, the proximal jejunum should be clamped in order to reduce intestinal overinflation and postoperative discomfort.  
In cases of difficult cannulation of the papilla, a guidewire can be passed through the cystic duct into the duodenum and retrieved by the endoscopist (so-called laparoscopic-endoscopic rendez vous).  
The technique of anterograde ES by inserting a sphincterotome through the cystic duct under duodenoscopic control has also been described. 
Another important contribution of flexible endoscopy to MIS in recent years has been through endoscopic treatment of LC complications.  
The toll of biliary tract injuries caused by the so-called “learning curve” has been quite high. ERCP and associated interventional techniques (endoscopic sphincterotomy ES, nasobiliary drainage, balloon dilatation, stenting) have been useful in the diagnosis and treatment of such complications (Figure. 1a and 1b).  
Leakage from the bile ducts or, more often, from the cystic duct, early or late stenosis and even transection of the biliary tract can in many instances be conservatively treated by endoscopy alone or in combination with percutaneous radiologic techniques. 
Again, by managing complications endoscopically, the principles of MIS are respected even when this new way of performing surgery fails or itself produces serious sequelae. 
A two-port technique for LC using microendoscopes has been described. In selected patients this technique can be considered a good alternative to the standard four-port procedure in view of a presumpted reduction in surgical trauma and postoperative pain. 

Esophagus.  
Gastroesophageal junction 

In the last few years, while new drugs, such as prokynetics but especially proton pump inhibitors (PPI), have improved the results of medical therapy, interest in surgical management of gastroesophageal reflux disease (GERD) has been rejuvenated by the evolution of laparoscopic procedures.  
Experience gained with open surgery has inspired the laparoscopic techniques currently in use; nonetheless the good cosmetic result, the little or no postoperative pain and the short hospitalization typical of MIS, have all contributed to increasing the number of patients affected by GERD for whom the gastroenterologist would advise a surgical opinion.  
As we know, GERD is a benign but complex, multifactorial disease; and careful evaluation and selection of patients represents the key to success of surgery. 
There is no doubt that some authors suggest a need for surgery in cases of GERD which is refractory to medical therapy.  
We think that when a patient does not respond to an appropriate medical treatment he is not the best candidate for surgery and the causes of his symptoms should be looked for elsewhere.  
The reality is that there are patients with moderate/severe esophagitis and who cannot easily change their lifestyle and who need continuos administration of PPI; some of these patients develop a psychological burden with a lifetime of medication dependence and they find it difficult to follow a rigid dietary and various behavioural rules.  
They can all be offered a surgical alternative. Surgery also plays a role in the control of symptoms such as asthma, hoarseness, cough, chest pain, aspiration, or because of the occurrence of complications, such as esophageal stenosis.  
Treatment of Barrett's esophagus remains controversial, with some authors advising antireflux surgery and others suggesting esophagectomy for severe dysplasia or photodynamic laser ablation or laser alone. 
Other considerations may play a role in the choice of treatment. In fact, due to the limited resources available for medical care and the high prevalence of GERD in many countries, the economic aspect of treatment strategy is becoming very important. A study from the United States would indicate a $ 1500 saving over a 10-year period for patients treated surgically. 
Under these circumstances, the pletora of reports on hundreds of patients treated for GERD by MIS now filling the literature compares strikingly with the few papers, emanating from specialised institutions only, published up to 5 years ago.  
Although no direct comparison between surgery and PPI has been reported to date, it has been clearly demonstrated that in patients with severe GERD Nissen fundoplication is more effective on symptoms and esophagitis than intermittent or maintenance therapy with conventional drugs.  
The best candidate for surgery is, in our opinion, the young, physically fit patient with moderate or severe disease and frequent relapses. 
Of the many different operations so far proposed and performed for GERD, each presenting its own pathophysiologic mechanism, the Nissen or Nissen-Rossetti technique, due to its high reliability born out by worldwide experience, is by general agreement the gold standard of any antireflux operation (Figure 2). 
This procedure is associated with a small but significant risk of postoperative complications such a paraesophageal herniation, hiatal stenosis and especially early and late dysphagia. 
When performing this technique by MIS, difficulties can be encountered because of hypertrophy of the left lobe of the liver, intra-abdominal obesity and periesophagitis following previous surgery. Cases with endobrachiesophagus should be treated by a Collis gastroplasty, but completion of this procedure by MIS is somewhat cumbersome.  
Decades of debates on the technical details of the open Nissen technique have now subsided to a general agreement on one fundamental principle: laparoscopic Nissen is a simple technique and unnecessary manoeuvres should be proscribed.  
Division of short gastric vessels has turned out to be useless in most instances; one study  demonstrated no difference between patients with or without short vessel division by 24-h pH recording manometry and symptom score. In fact, the gastric fundus only should be used for the wrap, in order to achieve a “floppy” Nissen; the mistaken use of the body of the stomach instead is the cause of excessive traction on the short vessel which may cause rupture and bleeding and also an early dysphagia.  
A recent study shows that the rate of reoperation and/or complication is related to individual surgical experience with this rate stabilizing after each individual surgeon's first 20 procedures. Also the length of operation stabilizes to not in excess of a mean 1.5 h.  
The outcome of laparoscopic procedures is not influenced by the preoperative grade of esophagitis. Compared to the open technique, laparoscopy seems to carry more risks of gastric and esophageal perforation through three identified mechanisms: improper retroesophageal dissection, forceful passage of bougies, and late suture pull-through.  
Of course the rate of such complication is related to the learning curve. In patients with esophageal achalasia, a cardioesophageal myotomy can be performed using the laparoscopic approach.  
There is no general consensus on the need for completing this operation with an antireflux procedure; some authors suggest a hemifundoplication by the Dor or a Toupet's technique.  
A recent study showed a competent lower esophageal sphincter (LES) and no pathological reflux on 24-h pH-manometry following a short myotomy.  
Our results demonstrate that lasting results come from a long myotomy completed by a circumferential fundoplication. This is a safe, effective and durable operation giving the advantages of laparoscopy in terms of less postoperative pain, early return to work, etc. and yet respecting the principle of open surgery.  
However, skill is required to perform myotomy during laparoscopy  to avoid the risk of incomplete muscular division or a mucosal perforation. 
Thoracoscopic removal of esophageal leyomiomata or resection of esophageal diverticula have been described. These operations are facilitated by intraoperative upper gastrointestinal (GI) endoscopy to point at the lesion and to ensure adequate retraction during dissection manoeuvres; moreover, following tumour removal, endoscopic insufflation allows for an easier suturing of the muscular layer of the esophagus. 
More often, intraoperative upper GI endoscopy is required to facilitate identification of the esophagus within the diaphragmatic pillars; this combined approach has become routine during the many operations performed laparoscopically on the gastroesophageal junction for achalasia or gastroesophageal reflux.  
Specially designed flexible fiberoptic bougies with translucent tip (Endolumina() can be used as well. With a 60 French outer diameter, these instruments were used to calibrate the gastric flap during a Nissen operation; a necessity not recognized by a recent trial and  in our experience. 

Oncology 

It seems to me that a discussion of the role of laparoscopy in oncology should be separated into its two components, diagnostic and therapeutic, the first surrounded by undisputed consensus, the second representing one of the most controversial issues of modern surgery. 
Shadowed by radiological imaging techniques in the late 1970s and 1980s, diagnostic laparoscopy has found a renaissance with the advent of MIS; preoperative evaluation of the peritoneal cavity has become frequent in emergency cases as well as in the case of patients with advanced cancers or lymphomas for whom preoperative investigations are doubtful or inconclusive. Evaluation of the local extent of the neoplasm and identification of microscopic intraperitoneal or hepatic dissemination, undetectable by even the most refined imaging tools, are easily achieved by laparoscopy using  local anesthesia and mild intravenous sedation; if indicated, biopsy and perlaparoscopic US are also possible. This approach has spared many patients unnecessary exploratory laparotomies. 
On the other hand, we wonder if therapeutic MIS in oncology is a reality, a prospect or a challenge. 
The reality is that today any abdominal operation for cancer can be completed laparoscopically, or with laparoscopic assistance, by extending a trocar incision by a few centimetres to allow for removal of the specimen or extracorporeally dividing the bowel, suturing the vessels and making the anastomosis.  
MIS in oncology is no longer a challenge because in the last 4 years we have become accustomed to laparoscopic total gastrectomies, hepatic resections, pancreatoduodenectomies, retroperitoneal extended lymphadenectomies for seminal tumours, etc., and official or semi-official registries of colo-rectal cancer patients have been established all over the world.  
Therefore, it seems to us that the controversy moves more in the direction of delicate ethical considerations, and here we have the prospect: what is the prospective value of MIS for a patient with cancer? Questions are addressed to the safety and the usefulness of the laparoscopic approach. In our review we will mostly refer to colorectal cancer, a common disease treated by laparoscopic surgery since 1991, which achieves good results with substantial follow-up. Safety in oncology not only involves morbidity and mortality but also long-term control of the disease. Study of specimens shows that adequate margins and similar numbers of lymphnodes can be obtained following open and laparoscopic resections.  
Pneumoperitoneum has been charged with being responsible for intraoperative dissemination of cancer, but no definitive proof has been obtained.  
Carbon dioxide has been shown to promote growth of tumour cells as compared to helium, but the clinical implications are still to be determined. An increased risk of implant of malignant cells in the trocar's wounds has been suggested. A review of the American Society of Colon and Rectal Surgeons Laparoscopic Registry of 480 colorectal cancer patients (minimum follow-up: 1 year) identified 5 wound recurrences (1.1%), a two-fold risk compared to the 0.6% reported for traditional resections by Reilly on 1711 patients (minimum follow-up: 3 years).  
Many reports compare open and MIS colon and rectal resections for cancer after a more than adequate follow-up, showing similar survival and recurrence rates. With regard to usefulness, it seems to me that the typical advantages of MIS are somewhat less readily recognizable in the field of oncologic surgery.  
Maybe postoperative pain is less, but the duration of the operation is quite often much longer and the duration of postoperative ileus and early feeding do not differ substantially.  
Therefore, prospect will imply use of new instrumentation or refinement of surgical technique in order not only to reduce the length of the operation but also to increase the number of surgeons able to perform these procedures. 

Solid organs 

Laparoscopy can be safely performed for the management of liver cysts, benign tumours or focal hepatic hyperplasia. Its use in the management of hydatid cyst, a widespread disease all over the world, has also had good reports.  
Partial cystectomy and omentoplasty is the procedure of choice; in some cases fenestration of the cystic wall can also be performed by YAG-Laser to reduce the risk of bleeding. Laparoscopic management reproduces the standard surgical treatment of these lesions and is followed by short and painless convalescence with rapid recovery.One of the most important problems in hepatic surgery is represented by the differentiation of benign tumours. In the case of hepatic metastases demonstrated laparoscopically, excision of the lesion can be performed during the operation. An alternative treatment is by cryotherapy or radiofrequency probes, also performed by MIS and open surgery. Major surgery, such as segmentectomy, lobectomy or hepatectomy, is feasible laparoscopically but experience is limited to the few cases reported. 
In patients with pancreatic cancer, diagnostic laparoscopy offers outstanding contributions to the definition of staging. Moreover, palliation of inoperable cases can be obtained by laparoscopic biliary and digestive by-pass. Chronic pancreatitis can be treated laparoscopically by a wirsung-jejunostomy or by a 70% distal pancreatectomy and splenectomy to obtain relief of severe pain; these procedures are feasible, safe and accompanied by accelerated recovery. Laparoscopic adrenalectomy, expecially in Cushing's syndrome, offers the potential benefit of a smaller operation with a faster hospital discharge compared to open surgery. 
Diagnostic laparoscopy and laparoscopic ultrasonography have recently been applied for diagnosis and localization of islet-cell tumours. A further step was taken by performing resection of these tumours with laparoscopic techniques.Within the last 4 years laparoscopic splenectomy has become widespread. It can also be performed safely in children, being now the procedure of choice in Hodgkin's disease, elliptocytosis, spherocytosis and idiopathic thrombocytopenia purpura.  

Surgery of obesity 

Obesity has always been a controindication to MIS, today it has found in laparoscopy one of the strongest promoters of the diffusion of the surgical management of this pathological condition. Surgery for morbid obesity is essentially based upon biliopancreatic and intestinal by-pass and upon operations intended to reduce gastric capacity. The former technique is difficult to perform laparoscopically, whereas vertical gastroplasty and gastric banding can be easily completed within 1-1.5 h. Gastric banding has become today the most popular operation, due to its technical ease and reversibility in case of complications. This procedure creates a small gastric space of only 40-50 ml with an adjustable outlet of 13-15 mm in diameter. The advantages of laparoscopy in these patients are many and obvious: there is no need for prolonged bed rest due to the absence of abdominal pain; patients can be mobilized on the day of surgery, thus reducing risks of deep vein thrombosis and of respiratory complications. Moreover, avoidance of long incisions reduces the chance of wound infection, a quite frequent and serious complication in obese patients. Hypercapnia from CO2 pneumoperitoneum represents the major drawback to performing laparoscopy on obese people, therefore, the duration of the operation must be limited. Alternative use of laparolift in these subjects is, of course, not applicable gasless laparoscopy is frequently used for other procedures, including colonic resection (Figura. 3). 

Outpatient laparoscopic surgery 

The new scenario of medical funding introduced by diagnosis-related groups greatly prizes short hospital stays. Patients are frequently admitted the day of the surgery, even prior to major procedures, and are discharged before the full clinical course is completed. The economic advantage introduced by MIS relies on the shortened hospitalization of patients treated by this technique which, by itself, counterbalances the increased costs of the dedicated operating room equipment. Under such circumstances, outpatient laparoscopy becoming more and more popular for procedures such as cholecystectomy, appendectomy and hernia repair.  
Voitk found outpatient surgery to be possible in 87% of cholecystectomies. Other reviews show that postoperative readmission rate following outpatient laparoscopy can be as high as 39% (50). What is true is that outpatient laparoscopy carries clear benefits for the economic system as a whole (hospital, social system, employers) but the patient, on the contrary, could be exposed to unnecessary risks, especially from delayed treatment of complications or occurrence of otherwise avoidable annoyances. Again, careful patient selection is paramount. Outpatient laparoscopy should not be offered to patients with cardiopulmonary disease or other major health problems, or who are simply elderly or who must undergo an operation longer than 1 h, or  who live alone or far from medical facilities: when these criteria are excluded, the rate of readmission following ambulatory laparoscopy falls to 5.9% only. Moreover, new experiences, such as the “recovery hotel” rooms at Yale University, provide a totally new perspective to keeping the patients under good medical care at reduced costs. 

Emergency laparoscopy 

As with oncologic patients, diagnostic laparoscopy has again found an important role in the emergency situations. Moreover, immediate treatment can be obtained in certain circumstances. Laparoscopic exploration of the abdomen does not require the resources of the operating theatre and it can be performed at the bedside in the intensive care unit. On the other hand, trained staff and dedicated equipment must be available 24 h a day for what may be  an infrequent procedure. Therefore, this facility seems advisable only for large level-2 trauma centers. Several emergencies may require laparoscopy, the most important being acute right lower quadrant pain, acute cholecystitis, perforated peptic ulcer or diverticulum, bowel obstruction, intra-abdominal haemorrhage and mesenteric ischemia. Differential diagnosis of right lower quadrant pain can be troublesome, especially in young females; emergency laparoscopy has reduced the number of unnecessary appendectomies and recovery from laparoscopic appendectomy seems somewhat better compared to the open procedure. Nonetheless, gangrenous appendicitis should be removed by traditional surgery, due to the high incidence of complications reported following MIS (up to 45%). Acute cholecystitis is diagnosed and treated by laparoscopy with the requisite good surgical skill required (Figure 4). A trend towards reduced mortality when compared with conservative management has been suggested. 
A perforated peptic ulcer requires immediate recognition and treatment, especially in those elderly patients for whom delayed diagnosis implies mortality rates as high as 90%. Treatment by MIS can be easy in duodenal perforation, on the anterior wall in most instances. Adequate control of gastric perforation may be quite difficult because of induration of the gastric wall; biopsy should always be taken. Repair of the posterior gastric wall requires open surgery. These procedures no longer need to be completed by vagotomy, because of the effectiveness of propton pomp inhibitors and eradication of helicobacter Pylori, if present, in reducing the risk of recurrence. On the other hand, there also seem to be limited indications for elective treatment of peptic ulcer disease by laparoscopic posterior truncal vagotomy and anterior seromyotomy or posterior truncal vagotomy and anterior highly selective vagotomy, which had been emphasized during the last 4 years. 
Minimal peritoneal contamination from a perforated diverticulum can be handled by repair and drainage. Nonetheless, resection with or without protective stoma, is to be recommended. It is worth mentioning that experience with elective sigmoid resection for diverticular disease is encouraging.  
The role of emergency laparoscopy in ruling out cases of small bowel obstruction is contraindicated in cases of intestinal overdistention, because of obvious risks of perforation and inadequacy of working space within the abdomen. Lysis of adhesion can be easily completed, if this is the cause of obstruction (Figure 5). Deep pelvic or retroperitoneal pathology cannot be evaluated by these means. 
Patients with suspected hemoperitoneum and who have an inconclusive pre-operative work-up can be evaluated by laparoscopy, especially following penetrating wounds or blunt trauma. False positive results of peritoneal lavage may be as high as 11-25%, and these patients can be spared unnecessary exploratory laparotomy.  
Mesenteric ischemia can be easily recognized and monitored by leaving a cannula in place for second-look inspection at 12-24 hour interval (Figure 6). Knowledge of the possibilities and limits of emergency laparoscopy can help the physician better to identify the correct timing and  indication for this procedure in such a delicate setting. 

Conclusion 

I believe that minimally invasive surgery is neither a myth, nor a reality of tomorrow, but a certainty of today which day-by-day continues strongly to be confirmed and consolidated, and which also involves the patient's decision in the choice of treatment. This paper indicates where we are with regard to MIS and we believe that this millennium will be concluded with clearer ideas, and less confusion on the topic. This will allow us to elaborate and spread a more combined approach to the medical educational, psychological and ethical terms. From this, we glean, the image and role of tomorrow's surgeons, who will have to operate in a third millennium society. For advanced MIS surgery the year 2000 is today. In fact, tridimensional vision, virtual reality, robotics, in one word the video-presence, is a reality which still needs a little technical perfecting, but which  will represent the technologic baggage necessary for future generations of surgeons who will operate wearing space suits and goggles, utilizing ever more complex and sophisticated means, moving in an almost surreal environment. Telesurgery, robotics and virtual reality will, I think, play a fundamental role in the future; I believe ours is the last generation of traditional surgeons. These, then, are the prospects which seem possible to me, but everything must be directed toward additional benefits for our patients, to whom we dedicate our work and our life. Enthusiasm for these new techniques will not undermine the principles of doctrine of our discipline; we will be able to say that the so-called minimally invasive surgery represents an authentic evolution of surgery and not a revolution, since tactile exploration is substituted by the eye-hand synchronizy.  
At this point we believe that the best results in performing MIS can be achieved by surgeons who have consolidated experience in endoscopy and as a means of diagnostic investigation, and who need to teach the method in a surgical environment. The indications, advantages and limitations of this new surgical approach can only be defined after serious and lengthy clinical practice with controlled trials. Yet, we are able to state that this surgery is a certainty of today which, prospectively, will continue to be confirmed and consolidated, and which will involve also the patient's compliance in the choice of intervention. Furthermore, the laparoscopic-endoscopic interface is becoming every day more and more intertwined. 

Alberto Montori 
Direttore della III Cattedra di Patologia Speciale Chirurgica e Propedeutica Clinica 
Università “La Sapienza” Roma 

Presidente del 6° Congresso Mondiale di Chirurgia Endoscopica e Mininvasiva  
(Roma 31 Maggio - 6 Giugno 1998)