Laparoscopic splenectomy using Ligasure. Preliminary experience.

BACKGROUND: Intraoperative bleeding is the main complication and main cause of conversion during laparoscopic splenectomy (LS). We present the advantages of the use of the Ligasure Vessel Sealing System added to lateral approach for achieving a safe vascular control. METHODS: Ligasure is an energy-based device which works applying a precise amount of bipolar energy and pressure to the tissue, achieving a permanent seal. We have performed a total of 35 LS in a 5-year period using different approaches and methods of dissection, including the anterior approach, monopolar coagulation, clips, endostaplers, and ultrasonic shears. In the last 10 patients (4 males and 6 females, mean age 24 yr) we employed a technique with 4 trocars, right semilateral position associated with the entire dissection of the spleen and vessels sealing (lower pole vessels, main vascular pedicles, short gastric vessels) performed with Ligasure. Six had thrombocytopenic idiopatic purpura (ITP), 2 hereditary spherocytosis and one each b-thalassemia and hemolytic anemia. RESULTS: Nine LS were completed with one (10%) conversion because of hilar bleeding due to accidental injury with Ligasure. The average splenic weight was 485 g (range 265-1800), with an average diameter of 16 cm (range 12-25). In all but one patients (the converted one) the intraoperative blood loss was less than 100 mL (range 50-100 mL, average 80 mL). No blood transfusion were needed. The average operative time was 120 min (range 90-165), including 2 patients undergoing combined laparoscopic cholecystectomy. There was no mortality, with one (10%) postoperative complication (thrombosis of the spleno-portal axis), treated with a conservative approach. The average postoperative hospital stay was 3.5 days (range 3-6). CONCLUSIONS: The use of Ligasure, associated with the lateral position, results in a gain of time and safety. Furthermore, the average intraoperative bleeding of this series is very low.

[Stomach lymphoma]. / Linfoma a localizzazione gastrica.

BACKGROUND: Primitive gastric lymphoma (PGL) is a rare tumour, and although its incidence is rising it is difficult to state the role of the various therapeutic methods in treating this disease. Aim of this study is to point out what sequence of treatment is more effective trying to find out some guidelines which can be useful in clinical practice. METHODS: Retrospective analysis of clinical data of 54 patients with PGL admitted at a University surgical department during 10 years. All the patients underwent neoadjuvant or adjuvant chemotherapy and D2 gastrectomy. Follow-up ranged from 6 to 120 months. Survival was related to: Mushoff's stage of disease, the grade according to the Working Formulation and the sequence of treatment. Statistical analysis was performed by Kaplan-Maier method and the difference between survival curves was compared by log-rank test. RESULTS: Mean postoperative hospital stay was 12 days and morbidity was 18%. Five and 10 years overall survival rates were 70 and 85%. There was a significant difference in survival between patients with high grade PGL and those with intermediate grade (p=0.0188) as well as in those with low grade (p=0.0435). Patients in stages IE-II1E had a significantly longer survival than those in stages IIIE-IVE (p=0.0123). Patients in stages IE-II1E underwent neadjuvant chemotherapy and surgery and survived longer than those in whom surgery preceded chemotherapy (p=0.0293) instead for patients in stages IIIE-IVE neoadjuvant chemotherapy shortened survival (p=0.0403). CONCLUSIONS: In personal opinion, in patients in stages IE-II1E chemotherapy should be carried out before surgery, while in those in stages IIIE-IVE the reverse scheme is more effective in achieving longer survival rates.

Laparoscopic cholecystectomy and unsuspected gallbladder cancer.

Gallbladder cancer is a relatively uncommon malignancy. Its presentation is similar to that of gallstone disease and sometimes with non-specific symptoms. Laparoscopic cholecystectomy has become the method of choice for removing the gallbladder in most benign conditions. Occasionally, unsuspected gallbladder carcinoma is encountered in association with laparoscopic cholecystectomy. Overall gallbladder cancers have a poor prognosis, despite surgery or adjuvant therapies. However, in selected cases, a favourable outcome can be expected and the less favourable predicted outcome can be improved. Management of patients with gallbladder cancer in different situations is discussed: gallbladder cancer noted post-operatively on final pathology, gallbladder cancer noted after removal of the gallbladder and opening of the specimen at the time of surgery, difficulty encountered at the time of dissection and resultant suspicion of gallbladder cancer, and diagnosis of extensive disease at initial placement of the laparoscope.

[Videolaparoscopic cholecystectomy. Experience and results in 1019 cases]. / Colecistectomia videolaparoscopica. Esperienze e risultati su 1019 casi.

BACKGROUND: Laparoscopic cholecystectomy is now worldwide considered the elective therapy for biliary lithiasis. Morbidity, mortality and conversion rates reported in the literature are assessed between 1 and 6%, 0 and 0.9%, 3.6 and 7.2% respectively. Data on personal experience with 1019 attempted laparoscopic cholecystectomy are reported. METHODS: In the period between 1991 and 1997 1019 laparoscopic cholecystectomy were performed. Patients were 361 males and 658 females (ratio M:F 1:2), with an average age of 51 years (range 5-85). Indications were: 647 symptomatic cholelithiasis, 28 hydrops, 121 empyemas, 76 cholecystocholedocolithiasis and 13 alithiasic cholecystopathy. RESULTS: Conversion was necessary in 61 cases, with a conversion rate of 6%. Mean duration of surgery was 65 minutes (range 30-240) with a mean hospital stay of 2.1 days (range 1-10). No deaths occurred in our series, with a morbidity rate of 1.8% (18 cases, 7 major and 11 minor). Only 1 case of bile duct injury (0.1%) is reported. CONCLUSIONS: In consideration of low conversion rate, low early and late morbidity, absence of bile duct injury, advantages for the patient and the opportunity of evolution of this surgery, laparoscopic cholecystectomy can be considered the standard treatment for biliary lithiasis.

[The use of the biofragmentable ring (BAR-Valtrac) in colon surgery]. / Utilizzo dell'anello bioframmentabile (BAR-Valtrac) nella chirurgia colica.

BACKGROUND: Clinical results of colic anastomosis using biofragmentable anastomosis ring (BAR-Valtrac) are presented. Such a method showed to be a real alternative technique to the usual ones. METHODS: Eighty-six colic anastomosis using BAR are collected, 76 of which performed as elective surgery and 10 in emergency. The patients were 47 males and 39 females, with a mean age of 64 years. In 63 cases the patients were affected by colic neoplastic disease, in 16 by complicated diverticular disease (stenosis or perforation) and 7 patients had neoplastic disease of other organs involving the colon BAR device was used in 48 colic reconstructions after segmentary resection and in 38 colic reconstructions after left hemicolectomy. In each case 31-34 mm BAR were used. RESULTS: No perioperative death occurred in our series. Only one case (2%) of anastomotic leak was observed, while in 3 cases (4%) intestinal canalization disorders occurred. No problems for ring expulsion occurred in any patient. Three late complications were observed, as three cases of asymptomatic substenosis discovered during instrumental follow-up and spontaneously cleared up. CONCLUSIONS: On the basis of clinical results, and according to those reported in literature BAR anastomosis is considered a safe, feasible and easy technique to perform colic anastomosis, even in emergency, limited to the intraperitoneal tract of the colon.

[Hernia repair with prolene mesh according to the Lichtenstein technique. Results of 692 cases]. / Ernioplastica con rete in prolene secondo Lichtenstein. Risultati su 692 casi.

BACKGROUND: Inguinal hernia repair with prolene mesh according to Lichtenstein "tension free" technique has gained great acceptance worldwide, showing efficacy to consolidate the posterior wall of the inguinal canal and to reduce recurrence risk because of tension on suture lines and postoperative pain. Personal experience of 692 hernias treated with this technique is reported. METHODS: From January 1989 to December 1997, 692 patients were treated according to Lichtenstein at the General Surgery Department of the San Gerardo Hospital. Mean age was 60 years (range 18-88) with a male: female ratio of 13:1. Surgery was performed under local anesthesia in 185 cases, under epidural anesthesia in 317 and under general anesthesia in 190. Hernia was primitive in 647 cases (411 obliquo-external and 236 direct), while in 45 patients it was a recurrent hernia. In this series, 619 patients had monolateral inguinal hernia, while 73 had a bilateral one. In 40 cases hernia was incarcerated and in 8 strangulated. RESULTS: Mean hospital stay was 2.3 days (range 1-8). Eleven (1.6%) early complications, were observed, with one periprosthetic infection which resolved after patch removal, 3 hematomas, 2 seromas and 2 wound infections. Furthermore, there were 32 (4.6%) late complications with only one recurrence (0.14%) in this series and 25 cases of persistent nerve irritation. CONCLUSIONS: The results obtained with Lichtenstein "tension free" repairs of inguinal hernias confirmed this technique as easy to perform, also under local anesthesia, and associated with low rates of complications and without recurrences.

[Sequential endo-laparoscopic treatment in patients with common bile calculi]. / Trattamento sequenziale endo-laparoscopico in pazienti affetti da calcolosi colecisto-coledocica.

BACKGROUND: Laparoscopic treatment of common bile duct (CBD) stones is gaining great acceptance worldwide, but actually it requires skills and technologies too expensive for a great part of general surgeons. So endoscopic removal of CBD stones before cholecystectomy is usually performed. Since 1991 in our department we started a policy of selective preoperative cholangiopancreatography (ERCP) in patients suspected for choledocholithiasis and waiting for laparoscopic cholecystectomy. METHODS: A retrospective study has been made on a population of 1100 patients who underwent elective laparoscopic cholecystectomy in the period between January 1991 and December 1997. They were 391 male and 719 female with a mean age of 52 years, 126 of whom (11.5%) were selected to have ERCP preoperatively because they had clinical, biochemical and ultrasound signs of the presence of common bile duct stones (CBDS). RESULTS: Successful cannulation of the CBD was achieved in 124 cases (98.4%), with failures due to ampullary diverticula. In 7 cases (5.5%) a precut was necessary to obtain cannulation. Sphincterotomy was performed in 113 patients (89.7%). In 93 patients (73.8%) stones were found (87 macrolithiasis and 6 microlithiasis); in 91 (97.8%) stones were removed in one (87) or two (4) endoscopic session. There were 2 major complications (one bleeding and one severe pancreatitis) due to ERCP or a sphincterotomy. Two patients developed symptoms from unsuspected common bile duct stones after LC and were removed endoscopically. No complications during LC were due to ERCP or ES. CONCLUSIONS: Selective preoperative ERCP is an effective way of clearing the CBD stones before laparoscopic cholecystectomy, with low rate of complications related to endoscopic and laparoscopic procedures, and short mean hospital stay (5.5 days), according to the concept of minimally invasive treatment.

Optimal decision boundaries for M-QAM signal formats using neural classifiers.

The application of neural classifiers for providing optimal decision boundaries of a warped and clustered M-QAM constellation affected by nonlinearity is analyzed in this paper. The classifier behavior, for the specific application, has been evaluated both by the carrier to noise ratio (CNR) degradation (DeltaC/N) due to nonlinearity for a target error rate P(c)=10(-3), and more thoroughly by classical figures of merit of the pattern recognition theory such as classification confidence and generalization capability. The influence of the probability distribution of the training examples and the effects of activation functions' sharpness (namely the temperature of the net) have also been investigated. The results, obtained on a simulation basis, indicate optimal matching with respect to upper bounds evaluated with some minor simplifying hypothesis, even if the overall method's effectiveness can be adequate only for mild nonlinearity conditions.