Biomedical subjects
Publications and source records attributed to P Petropoulos.
We demonstrate a novel frequency-resolved optical gating (FROG) configuration based on cascaded second-order nonlinear interactions. Its implementation in a 2.6 cm long quasi-phase-matched LiNbO3 waveguide allowed high-quality retrieval of 2 ps to 80 fJ pulses at 1.56 microm.
OBJECTIVES: To assess the efficacy of early thromboprophylaxis throughout pregnancy in women with previous history of first trimester recurrent miscarriages of unknown aetiology. METHODS: Low dose aspirin and low molecular weight heparin (LMWH) were administered from the day of detection of the fetal heart up to the 37th week, in two groups of patients of known (Group A, n = 24) and unknown aetiology recurrent miscarriages (Group B, n = 27). RESULTS: The success rate (viable pregnancy >24 weeks) was high and equally effective in both Groups A and B (83.3% and 85.1%, respectively). The complications recorded (pre-eclampsia, IUGR, placenta abruptio, injection site heamatomas and skin reactions) were more prevalent in Group A but of no significant difference. No abnormal bleeding was observed during vaginal delivery or caesarean section. CONCLUSIONS: Our results reaffirm previous reports that the use of LMWH in combination with low dose aspirin throughout pregnancy is safe and effective. It was also shown that the treatment is equally effective against recurrent miscarriages in both groups of patients, of known and unknown aetiology.
PURPOSE: The aim of this study was to assess the feasibility and safety of laparoscopic surgery for the cure of colorectal cancer and to evaluate the oncologic follow-up. METHODS: Between March 1993 and December 2000 103 patients with colorectal cancer were treated by laparoscopy. Surgical, pathologic and follow-up data were recorded in a prospective registry database and analyzed by type of resection. RESULTS: A total of 42 women and 61 men with a mean age of 66.7 years underwent 9 right hemicolectomies, 6 left hemicolectomies, 35 sigmoidectomies, 41 low anterior resections and 12 abdominoperineal resections. Conversion was necessary in 14.5%. Postoperative complications occurred in 21 patients (20.3%) and decreased with experience. Hospital mortality was 0.9%. All cancers (31% stage UICCI, 28% stage II, 37% stage III et 3% stage IV) were resected with tumor-free margins and the mean number of lymph nodes was 19.6. Patients resumed solid diet on the second postoperative day and mean hospitalization was 12.6 days. Three port site recurrences, 4 local recurrences and 10 distant metastases occurred after a mean follow-up of 34.5 months (8-92). CONCLUSION: Laparoscopic colorectal cancer surgery is technically feasible with acceptable morbidity and low mortality. An oncologic adequate resection can be performed. To determine whether the recurrence rates and the survival data are equivalent to open surgery, prospective randomized trials are necessary.
BACKGROUND: Although the rate of complications from laparoscopic Nissen fundoplication is low and the adverse postoperative sequelae are well known, both are disturbing for the patient. Identifying risk factors could be helpful in the better selection of patients for this procedure. METHODS: A retrospective review of 126 patients with a mean follow-up period of 3.5 years was conducted. The patients' demographics, pre- and postoperative symptoms, and outcomes were analyzed and compared. RESULTS: Three groups of patients were distinguished: (group 1) 9 patients with intraoperative complications (5 with perforation, 3 with hemorrhage, 1 with pneumothorax); (group 2) 16 patients with postoperative complications (5 with severe dysphagia, 4 with failure, 2 with pneumonia, 2 with incisional hernia, 1 with intestine perforation, 1 with fundoplication herniation, 1 with infection, 1 with gastric ulcer); and (group 3) 101 patients without any complications. The patients'demographics, preoperative symptoms, and preoperative studies were comparable in all three groups. The body mass index (BMI) was significantly higher (p < 0.05) statistically in group 1 (32.4 kg/m2) and group 2 (33.6 kg/m2) than in group 3 (28.7 kg/m2). However, the Visick grade and the subjective outcome were similarly good in all three groups. CONCLUSIONS: Although preoperative studies and symptoms do not seem to predict complications of laparoscopic Nissen fundoplication, patients with an increased BMI were at increased risk for complications in this study. Therefore, such patients should be counseled appropriately regarding the greater likelihood of intraoperative and postoperative complications.
Laparoscopic colorectal surgery hasn't been generally accepted yet. We present here our experience of 449 operations performed with this method. More than a quarter of the indications were for malignancy. Conversion rate was 9.3% for the benign diseases and 14.1% for the malignant ones. Operating time was longer compare to open surgery. Postoperative complications were 9.9% for benign and 23.6% for malignant diseases. Of those complications 7.1% concerned anastomotic leakages. Four patients presented with port-site metastases and this in the beginning of our experience. Mortality rate was zero for the benign group while it was 1.6% for the malignant one. According to our experience we believe that laparoscopic colorectal surgery offers a satisfactory minimal invasive alternative. Technological advances such as the harmonic scalpel or new visual techniques give more possibilities for better application of the method. Randomised studies, running actually, should allow us to say in the following years, if this method could be a widespread standard.
Laparoscopic procedures performed for diagnostic or staging purposes or even for a treatment, incorporate a certain risk for port-sites metastases. That possibility seems more potential with this method than with the open procedures. According to the works of Hugues, Welch and after that of Reilly, we do know that the percentage of wound metastatization in median laparotomies should be below 1%. In colorectal surgery this complication has been described with an incidence of 21%. Diverse factors influencing this phenomenon are reviewed. Nowadays the overall incidence of this complication seems to be significantly lower and two recent papers on laparoscopic colorectal surgery show an incidence varying between 0.2 and 1.1%. The oncological significance of such a secondary tumoral manifestation is not yet known. Is it a laproscopy-related complication or just a sign of immunosupressed host? More studies are certainly useful to precise the answer.
The aim of this study was to estimate the percentage of women who asked for pregnancy termination as an alternative to using family planning. The reasons given for requesting termination were documented and evaluated. During a 4-year period, 663 women came to the Family Planning Department. Four hundred and ninety-one (77.6%) were pregnant, in the first trimester of pregnancy and requesting an induced abortion. Consultation and counselling resulted in a 25% decrease in the number who finally had their pregnancies terminated. The low socio-economic status of most of the women and the negative attitude of our society towards an unmarried mother remain the main reasons for a high rate of therapeutic abortion.
A case of an anatomical variation of the arterial vessels in the popliteal fossa, leading to a vascular transection during a total knee revision is presented. The authors believe this complication should be considered in all cases of knee revision surgery.
Perforation of the colon during colonoscopy for diagnostic or therapeutic purposes is an important but not a frequent complication. Bibliographic controversies exist upon the type of treatment either conservative or surgical. In the late years reported cases favorise a trial for conservative treatment under optimal clinical conditions. We report our late experience with 3 cases of iatrogenic colonic perforation treated laparoscopically. Direct visualisation of the local status, the possibility of simple colonic oversew, abdominal toilette and drainage are the advantages of the method on which it should be added the psychological comfort for the surgeon and his gastroenterologist.
The aim of this work is a critical analysis of our results with primary laparoscopic resection and anastomosis of the colon for diverticulitis. From October 1993 to October 1997, 171 patients with a mean age of 60 years (97 males, 74 females) have been operated laparoscopically. 95 patients were operated electively after many episodes of acute diverticulitis and 76 patients in the acute phase, of whom 11 patients presented a colovesical fistula. 6 left hemicolectomies and 165 sigmoid resections were performed. Among the sigmoid resections 11 patients with simultaneous resection of a colovesical fistula are included. The operating time for elective cases was between 130 and 280 minutes with a mean of 180 minutes, for acute cases the time was between 75 and 410 minutes with a mean of 205 minutes. The conversion-rate was 10.5%: problems with the instruments n = 2, impossibility to pass the stapler n = 4, severe diverticulitis n = 7, iatrogenic lesion of the ureter n = 1, perforation of the transverse colon by the trocar n = 1, extended adhesions n = 2, hemorrhage n = 1. The morbidity was 10%: abdominal wall hematoma n = 1, intraabdominal hematomas n = 2, wound abscesses treated surgically n = 2, conservatively treated intraabdominal abscesses n = 2, anastomotic leaks treated with open procedure n = 2, anastomotic leaks with fistulization n = 4, treated once with laparotomy and 3 times conservatively, sepsis 3 times treated conservatively. As late complications (3.5%) we experienced: a bowel obstruction in 2 patients treated with open procedure, herniation at the trocar sites in 3 cases corrected surgically and an anastomotic stenosis, that had to be reoperated after an unsuccesful dilatation. Analgetic requests have been decreased to the half in comparison to the classically operated patients. The mortality: 1 patient (0.6%) died due to a fasciitis. The duration of the hospitalisation was 8.4 days in average (3-32 days). We can conclude that laparoscopic colon resection should be considered as an adequate procedure for the treatment of inflammatory processes. A large experience in laparoscopic surgery with continuous training of the surgeon is the prerequisite.
There is nowadays no current randomised study able to answer if a diverting colostomy is necessary or not in the surgical management of civilian colon trauma. We report our experience on 13 cases treated during the period from 1977 to 1997. There were 3 stab wounds, 4 gunshot traumas and 6 perforations of the colon caused by blunt mechanisms. Four patients underwent a primary colonic closure and 9 others a primary resection with anastomosis. In none of all our cases a diverting colostomy was performed. We experienced a fatal complication once and this was due to an underestimated segmental ischemia of the colon after blunt injury. Reviewing the late publications together with our modest experience we are allowed to conclude that primary repair without a stoma is the treatment of choice when the tissues show a good vascularisation. This often is the case with stab wounds and low velocity gunshot traumas. We would prefer a diverting colostomy in cases of blunt trauma of high energy and while haemodynamic instability makes the estimation of adequate tissue vascularisation difficult. Colonic lesions due to high velocity bullets should be managed as if they where wounds of war.
During laparoscopic cholecystectomy the frequency of lost stones due to torn gallbladder is from 9-40%. We have had occasion to treat three such complications: one giant right side abscess 27 months after the operation, one abscess of a port site which became a sinus with discharge of pus until complete evacuation of the stones 6 months later, and one case of dyspareunia and tenesmus cured only 33 months later by extraction of two stones from the pelvis. The first represents one case out of our first 480 laparoscopic cholecystectomies, while the other two were first operated on in another hospital. In the literature we have found 39 publications involving 53 cases. We have also noticed three medical papers written before 1987 with this type of complication, once 10 years after the initial operation. Since intraperitoneal lost gallstones have increased in frequency we expect more of these cases in the future. We conclude that it is reasonable to try to evacuate the spilled stones through laparoscopy and not to convert, except in the case of a large stone or a number of stones. Tearing of the gallbladder with lost stones must be mentioned in the protocol, so that it can be raised and included in differential diagnosis of any complications. Treatment must aim for retrieval of all stones, simple drainage being usually insufficient.
In order to assess if an oral glucose load has any effect on serum prolactin levels in patients with polycystic ovary syndrome (PCOS), an oral glucose tolerance test (OGTT) was performed in 30 patients with PCOS and 20 controls, with normal or abnormal body mass index (BMI). OGTT resulted in decreased prolactin levels, being significant only in patients with PCOS and in controls with normal BMI. Our results show that obesity is an important inhibiting factor of serum prolactin level suppression which occurs with a mild suppressive test, as the OGTT; however, hyperandrogenemia may also play an inhibiting role in serum prolactin level suppression.
Leiomyoblastoma is a rare, smooth muscle tumor of the stomach that occurs chiefly in the antrum. We present the case of a 51 year old man suffering from asthenia and mild upper abdominal pain. Investigations showed a big exculcerated tumor of the lesser gastric curvature. He underwent a subtotal gastrectomy for a non-metastasizing leiomyoblastoma, grade 1. But already 5 months later, he developed an invasive non-resectable local recurrence of high grade malignancy and died 3 month after a second look. Those tumors affect middle-aged patients who present usually upper gastrointestinal bleeding or peptic ulcer-like symptoms. Although the large majority of leiomyoblastoma are benign, malignancy occurs in up to 10% of cases. A large surgical resection of the tumor (including the total thickness of the gastric wall) or a partial gastrectomy is recommended.
Explore the source record for details and available documents.
Twenty patients with polycystic ovarian syndrome and with or without insulin resistance, and 20 healthy women (controls) underwent an oral glucose tolerance test, which resulted in a short duration but significant increase of serum insulin levels. Serum testosterone, androstenedione and dehydroepiandrosterone sulfate levels were estimated before and 180 minutes after administration of 75 gr. dextrose. Our results, three hours after dextrose administration, showed that: (1) serum testosterone levels decreased significantly, (2) serum androstenedione levels decreased but not significantly, and (3) serum dehydroepiandrosterone sulfate levels were not altered. The observation of decreased ovarian androgen levels after induced hyperinsulinemia is very interesting, the explanation, however, is quite difficult. This unexpected ovarian androgen response needs further investigation.
We reviewed in a retrospective study all our 616 electively operated colons over 15 years from 1976 to 1990 for morbidity and mortality depending the antibiotic prophylaxis. Interventions were performed on 578 patients with a mean age of 65.5 + 13.7 years; in 38 cases there was an earlier elective colic operation. The sex ratio was 1.26 men to 1 woman. 71.8% of the indications were adenocarcinomas of the colon. All other diagnostics, as well as different types of interventions were included in the study. All interventions was preceded by large bowel preparation. The colic anastomosis were almost always handswen in two layers. Until 1982 systematically, we gave prophylaxis by combination of aminoglycoside with metronidazole or clindamycin, n = 329 (53.4% of 616). We then changed to ceftriaxone, n = 287 (46.6% of 616). Ceftriaxone was applied in single dose (n = 142), in multi doses (n = 71) and combined in almost all cases with metronidazole (n = 74). We found significantly better morbidity and mortality results with ceftriaxone than in the aminoglycoside combined group: The ceftriaxone group had a septicemia or colocutaneous fistulas requiring reoperation incidence of 1.4% (4/287) versus 4.6% (15/329) (p = 0.023). Mortality decreased from 4.9% (16/329) under aminoglycoside combined prophylaxis to 1.74% (5/287) in the ceftriaxone group (p = 0.033). The infection rate of the surgical accesses diminished from 13.1% (43/329) to 8% (23/287) under ceftriaxone (p = 0.043).(ABSTRACT TRUNCATED AT 250 WORDS)
Pleural mesotheliomas are uncommon tumors that can be classified as localized fibrous or diffuse malignant. The frequency in the general population is low and, as it concern the diffuse malignant type, exposure to asbestos, significantly increases the incidence. The most common symptoms are chest pain, short of breath and cough and the roentgenological findings are solitary or multiple pleural nodular lesions. The fibrous type can be excised and recurrence rarely occurs, but the malignant type does not respond either to chemotherapy or to radiotherapy and surgical measures offer only palliation. Thoracoscopy is a possibility of surgical excision in a case of localized mesothelioma and in case of diffuse type it contributes to the diagnostic yield, the open surgical procedures to be considered only in functionally operable patients.