Videoendoscopic Surgery Research Articles

Le « pneumocou » dans la vidéocervicoscopie : technique opératoire et limites anatomiques

The aim of this study was to describe a technic in order to create a gas space “pneumoneck” during videoendoscopic surgery of the neck and to determine the anatomical limits of this space. Data were based on a surgical experience and on the dissection of two corpses. This space was located between the two layers of the pre-tracheal lamina of the cervical fascia. This space was enclosed and favourable to detachment with insufflated gas without subcutaneous emphysema. This approach can be used for parathyroid and thyroid surgery.

Minimally invasive surgery for esophageal achalasia.

Esophageal achalasia is characterized by loss of peristaltic activity and failure of relaxation of the lower esophageal sphincter (LES). The characteristic dysphagia may be alleviated by surgery, dilations, or botulinum toxin injections. Video-endoscopic surgery is used increasingly. This paper reports our experience with 142 consecutive achalasia patients treated by laparoscopic Heller myotomy and Dor antireflux fundoplication and followed for a median 26 months. Overall, the actuarial lifetable analysis showed a 90% probability of a patient's being symptom free over a 5-year period. Radiologic assessment showed a significant reduction in esophageal diameter and manometry a significant reduction in the resting tone and residual pressure of the LES. Twenty-four-hour pH monitoring showed postoperative reflux in 6.7% of patients. Persistent dysphagia or chest pain (i.e., failure of treatment) were reported by 15 patients (10.6%): 14 of them were subsequently treated with multiple pneumatic dilations, which were successful in 12 cases. Laparoscopic Heller myotomy with Dor fundoplication is a feasible and effective treatment for achalasia, with an actuarial success rate of 90% at 5 years. With additional dilation, a 98% success rate can be achieved.

Performing laparoscopic surgery is significantly more stressful for the surgeon than open surgery.

The awkward visual and physical interface of video-endoscopic surgery (VES) has been shown to increase the physical workload of the surgeon, yet there is a lack of objective information on the mental effort and stress demanded by VES techniques. This study addresses the hypothesis that VES is more stressful than open surgery using an ergonomic analysis of surgical tasks in a laboratory setting. A portable ergonomic work station was developed using a software Virtual Instrument (VI) interfaced with electronic hardware to compare the mental workload of 28 surgeons. The task was knot tying. The independent variable was work condition: rest, open technique, or VES technique. Dependent variables were tonic skin conductance level (SCL), electrooculogram (EOG), and subjective reports of concentration (CON) and stress (STR). Statistical analysis used nonparametric methods. Subjects tied fewer knots using the VES technique (p < 0.05). The SCL increased progressively from rest to the open task to the VES task (p < 0.05), correlating with the subjects' reported increase in mental stress level (p < 0.05). Eye blinks decreased from rest to the open task (p < 0.05), consistent with the subjects' reported increase in level of mental concentration. From the open to the VES task, eye blinks increased (p < 0.05), as would be expected given the greater demands of the VES task. Experienced subjects demonstrated less variability in SCL levels across tasks. VES technique requires greater concentration and places greater mental stress on surgeons than to open surgery. More experience with VES may decrease this effect. Studies are needed to improve the human-technology interface the stress.

Minimally invasive lung and pleural biopsies using 2-mm and standard thoracoscopic equipment.

Videoendoscopic surgery is commonly used to obtain a definitive diagnosis in a patient with pleural lesions or pulmonary infiltration of unknown etiology. We have performed minimally invasive pleural and lung biopsies, using 2-mm mini-videoscopic instruments supported by standard thoracoscopy via one 11.5-mm port, in 10 patients. These involved 8 patients with diffuse pulmonary infiltration, and two with diffuse pleural thickening. They underwent thoracoscopic pulmonary wedge resection and pleural biopsy using one 11.5-mm port and two or three 2-mm mini-ports. The mean operating time was 37 minutes. This procedure was successful in establishing a definitive diagnosis in each patient. Complications included subacute acceleration in pulmonary infiltration in one patient. No patient complained of pain or discomfort at the 2 mm-thoraco port sites. Healing of this port site resulted in excellent cosmesis. Mini-videoscopic surgery supported by standard thoracoscopic equipment can be used to perform lung or pleural biopsy less invasively than standard thoracoscopic approach.

Endoscopic surgery: fit for malignancy?

Neither experimental nor clinical data confirm the repeatedly published opinion that video-endoscopic surgery promotes tumor growth or the occurrence of implantation metastases in cancer patients. On the contrary, alterations due to pneumoperitoneum by the application of different gases, pressures, and temperatures might provide the basis for a new therapeutic approach to cancer surgery. Oncologically adequate resections defined by such terms as "no touch isolation" and "monobloc resection" can be performed video-endoscopically in a variety of intraabdominally or intrathoracically located cancers if a standardized technique is used. The benefit of video-endoscopic surgery is limited in large tumors, especially if they have reached the organ surface. There is still a major deficit in the clinical evaluation of video-endoscopic interventions in most oncologic diseases. Randomized studies comparing video-endoscopic and conventional surgery have been reported only for the resection of colorectal carcinoma. They show that laparoscopic resections can be performed with a minimum of postoperative complications to the same extent as conventional resections and offer several advantages during the early postoperative period. No reliable data from comparative trials are as yet available on the long-term results.

Natural protective mechanisms against endoscopic white-light injury in the fetal lamb eye

Objective: To evaluate light transmission, possible light trauma, and techniques for protection of the fetal eyes during intrauterine videoendoscopic surgery in a sheep model. Methods: In vitro studies were done at various gestational ages, including spectrometry of light output by a halogen light source and telescope and light transmission by spectrophotometry in the range of 180–3000 nm through amniotic fluid (AF) and fetal eyelids. In vivo electron-microscopic, morphologic analysis of the retinas of 65-, 95-, 108-, and 112-day-old fetal lambs with ( n = 8) and without ( n = 8) 30 minutes’ light exposure to the open eye was also done. Results: The light spectrum at the tip of the telescope was 400–750 nm, with a maximum irradiance of 3 × 10 −3 W/cm 2 at 580 nm. In the ultraviolet spectrum (less than 300 nm), irradiance was less than 0.5 × 10 −3 W/cm 2. Light transmission through ovine AF ranged from 30% at 300 nm to 89% at 700 nm at 84 days’ gestation, decreasing to less than 0.01% (300 nm) and 70% (700 nm) at 112 days. Fetal eyelids did not transmit more than 1% of light (any wavelength). After direct in vivo light exposure, no retinal damage was found. Photoreceptors were present from 108 days onward, but chromophores were scant or absent at all ages studied. Conclusion: The light spectrum of a standard endoscope is limited to 400–750 nm; ultraviolet light is filtered out. The AF transmits harmful blue light poorly. Fetal eyelids seem to protect the eye by extremely low transmission and light dispersion. Even with the eye open, no morphologic retinal damage was found. The strong light sources used with fetal endoscopy did not appear to pose a threat to the fetal retina.

Alternativa para ligaduras em cirurgias videoendoscópicas ou convencionais, com emprego de fitas de nylon: um estudo experimental

Os autores apresentam a proposta de utilização de fitas de nylon (braçadeiras) em cirurgias videoendoscópicas ou convencionais. Estas braçadeiras foram idealizadas para amarração de cabos elétricos. Efetuaram estudo experimental em ratos brancos (teste de comportamento biológico) e cães (ligaduras vasculares e de intestino) com bom resultado técnico e demonstrando escassa reação tecidual na presença deste material. Ficaram confirmadas a exeqüibilidade, a praticidade, a segurança e a economia na utilização das mesmas, sugerindo que possam ser aceitas como um método alternativo na prática cirúrgica.

Surgical technology and the ergonomics of laparoscopic instruments.

Laparoscopic surgery provides patients with less painful surgery and a more rapid recovery, while requiring that surgeons work harder and in a more remote manner from the operating field. Cost-containment pressures on surgeons demand efficient surgery, whereas the increased technological complexity and sometimes poorly adapted equipment have led to increased complaints of surgeon fatigue and discomfort during laparoscopic surgery. There is, therefore, a need to evaluate the ergonomic integration and suitability of the laparoscopic operating room environment to address the issues of efficiency, safety, and comfort for the operating team. This approach is particularly important in the design of laparoscopic surgical instruments. A review of the literature on the biomechanics of laparoscopic surgical instrument use was combined with data from the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) Ergonomics Questionnaire and demonstration station. Laparoscopic instruments suffer from ergonomically inadequate handle designs and inefficient handle to tip force transmission, which lead to surgeon fatigue, discomfort, and hand paresthesias. Improvements in the design of laparoscopic instruments are needed to decrease the work and discomfort of tissue manipulation during video-endoscopic surgery.

Operative fetoscopy: new perspective in fetal therapy?

In a limited number of conditions in utero surgery may be life-saving, such as some cases of congenital diaphragmatic hernia, cystic adenomatoid malformation of the lung, sacrococcygeal teratoma and lower urinary tract obstruction. Postoperative premature labour and its extreme invasiveness have been major drawbacks for open fetal surgery. More recently the merger of fetoscopy and advanced video-endoscopic surgery has been the basis of the concept of endoscopic fetal surgery. In order to evaluate the opportunities of ‘fetendo’ surgery, animal models have been developed to test the safety of the endoscopic approach, and the feasibility of surgical manipulations on the fetus. In the non-human primate, a lesser invasiveness of endoscopy over open surgical approach was demonstrated, by a significant decrease in uterine activity in comparison with hysterotomy. The main application of fetoscopy today is the surgical treatment of complicated or abnormal monochorionic twin gestations. Fetoscopic laser coagulation of chorionic plate vessels is suggested as a causal therapy for severe feto-fetal transfusion syndrome. Survival rates are around 55 per cent with an incidence of five per cent of neurological morbidity. Fetoscopic cord ligation is associated with a 66 per cent survival rate, but unfortunately also with a risk of 30 per cent for PPROM prior to 32 weeks. Although still in its early experimental phase, endoscopy seems to offer new hope for surgical fetal therapy. Though conceptually very tempting, the development of endoscopic fetal surgery should follow the formal guidelines, as earlier formulated for open surgery by the International Fetal Medicine and Surgery Society. The prospective registration of worldwide experience is advocated and a randomized trial of laser therapy versus amniodrainage is announced. © 1997 by John Wiley & Sons, Ltd.

Operative fetoscopy: new perspective in fetal therapy?

In a limited number of conditions in utero surgery may be life-saving, such as some cases of congenital diaphragmatic hernia, cystic adenomatoid malformation of the lung, sacrococcygeal teratoma and lower urinary tract obstruction. Postoperative premature labour and its extreme invasiveness have been major drawbacks for open fetal surgery. More recently the merger of fetoscopy and advanced video-endoscopic surgery has been the basis of the concept of endoscopic fetal surgery. In order to evaluate the opportunities of 'fetendo' surgery, animal models have been developed to test the safety of the endoscopic approach, and the feasibility of surgical manipulations on the fetus. In the non-human primate, a lesser invasiveness of endoscopy over open surgical approach was demonstrated, by a significant decrease in uterine activity in comparison with hysterotomy. The main application of fetoscopy today is the surgical treatment of complicated or abnormal monochorionic twin gestations. Fetoscopic laser coagulation of chorionic plate vessels is suggested as a causal therapy for severe feto-fetal transfusion syndrome. Survival rates are around 55 per cent with an incidence of five per cent of neurological morbidity. Fetoscopic cord ligation is associated with a 66 per cent survival rate, but unfortunately also with a risk of 30 per cent for PPROM prior to 32 weeks. Although still in its early experimental phase, endoscopy seems to offer new hope for surgical fetal therapy. Though conceptually very tempting, the development of endoscopic fetal surgery should follow the formal guidelines, as earlier formulated for open surgery by the International Fetal Medicine and Surgery Society. The prospective registration of worldwide experience is advocated and a randomized trial of laser therapy versus amniodrainage is announced.

Achalasia: what's new in diagnosis and treatment?

Achalasia is an esophageal motility disorder of unknown cause, characterized clinically by dysphagia and regurgitation and diagnosed by manometry and/or barium esophagogram. Good long-term symptomatic relief can be achieved with pneumatic dilatation and myotomy. Botulinum toxin injection and videoendoscopic surgery are being evaluated as less invasive forms of therapy.

Gasless video-endoscopic implantation of aortobifemoral vascular prostheses via extraperitoneal approach in the animal experiment

The gasless videoendoscopic implantation of GELSOFT aortobifemoral vascular prostheses times 6 x 6 mm in diameter using an extraperitoneal approach was tested in ten porcine experimental models at the Surgical Department of the University of Cologne, Germany. Gasless videoendoscopic surgery is performed with a laparolift-laparofan system. Aortobifemoral GELSOFT prostheses were successfully implanted in nine of ten animals, whereby one animal died during preparations for surgery of massive coronary infarctions. Average surgical durations using the extraperitoneal approach were 270 min. Dissection of the infrarenal aorta until occlusion took 45 min, average aortic occlusion 75 min, and iliacofemoral occlusion 45 min for the left side and 75 min for the right side. After successful videoendoscopic implantation of aortobifemoral GELSOFT prostheses all nine animals underwent laparotomy and resection of the aortobifemoral prosthetic segment. The quality of the endoscopically sutured aortic end-to-side anastomoses was examined in vitro under artificial circulation of glycerol/Ringer's lactate solution for evaluation of possible leakage and bursting pressures and then compared to conventionally sutured end-to-side anastomoses of 6-h-old porcine abdominal aorta and GELSOFT prostheses 6 mm in diameter. The maximum bursting pressure of all endoscopically sutured anastomoses was 480 mmHg mean pressure: the minimum was 140 mmHg mean pressure. The minimum leakage per minute was less than 10 ml/min for systolic pressure values between 120 and 350 mmHg. All endoscopically sutured aortic end-to-side anastomoses were comparable to conventionally sutured anastomoses concerning in vitro evaluation of bursting pressure and leakage per minute.

Videoendoscopic vascular surgery on aortoiliac vessels. An experimental study.

In order to avoid the postoperative complications following conventional surgical treatment of aortoiliac atherosclerotic occlusive disease, a new concept in videoendoscopic vascular surgery on the infrarenal aortoiliacal artery was created. New instruments for endoscopic vascular surgery were therefore developed. Having elaborated the practicability of "videoendoscopic surgery" in four short-term pilot studies in piglets, we performed a standardized acute study in healthy male piglets (32 +/- 2 kg). Blood flow was monitored ultrasonically in the femoral arteries and systemic and hemodynamic parameters were evaluated in all animals. The investigation regarding ultrasonically monitored blood flow in the femoral arteries (four aortofemoral bypasses, four iliac patchplasties) and other systemic, hemodynamic parameters after videoendoscopic vascular reconstruction revealed positive results. The following series of standardized long-term animal experiments revealed that 2-7 weeks after the aortofemoral bypass grafting (n = 5), the animals were all doing well. The angiographic examination showed that the prostheses were patent. Even though it was possible to carry out the endoscopic vascular method according to the rules of conventional vascular surgery, further experimental research and development of endoscopic instruments have yet to be done in order to optimize the new surgical method. This is the subject of our ongoing long-term animal studies.

Fetal endoscopic (‘Fetendo’) surgery: The relationship between insufflating pressure and the fetoplacental circulation

Application of video-endoscopic surgery to the gravid uterus provides a new treatment option for the fetus with a correctable congenital anomaly. “Fetendo” surgery requires temporary enlargement of the uterine cavity to create a working space. Volume expansion of the amniotic space raises intrauterine pressure, which could increase placental vascular resistance and thereby reduce placental blood flow. To test this hypothesis, the authors developed a fetal sheep model to examine the relationship between insufflating pressure and flow in the placental circulation. Fetoplacental blood flow was measured via ultrasonic flow probes placed around the fetal common umbilical artery and the maternal uterine artery in five anesthetized 120-day-gestation ewes. Invasive feto-maternal monitoring permitted synchronous measurement of fetal mean arterial pressure, fetal central venous pressure, maternal mean arterial pressure, amniotic pressure, and fetal oxygen saturation, with calculated values for fetal and maternal placental vascular resistance. Amniotic pressure was raised from 10 mm Hg to 40 mm Hg in 5-mm Hg increments by a combination of saline amnioinfusion and external uterine compression. At amniotic pressures of 20 mm Hg or less, placental blood flow was preserved; however, elevation of amniotic pressure above 20 mm Hg resulted in a significant decrease in placental flow, with concomitant fetal hypoxia. The authors conclude that the relationship between intrauterine pressure, flow in the placental circulation, and fetal oxygen delivery must be considered when selecting intrauterine insufflation pressures for hysteroscopic intervention.

Acquisition of eye-hand coordination skills for videoendoscopic surgery

Evaluation of eye-hand coordination skills in relation to experiential human factors may lead to improved instruction for videoendoscopic surgical skills acquisition. Twenty-nine subjects (medical students or residents in surgical specialties) volunteered to perform three exercises of increasing complexity in an "inanimate" trainer system that simulated the eye-hand coordination tasks inherent in a laboratory videoendoscopic surgical environment. Fourteen subjects participated in a biweekly practice program of 4 weeks duration using an inanimate trainer. Fifteen subjects had no practice on the laparoscopic trainer during the 4 weeks. Both groups were tested after demonstration on three exercises at the beginning and end of a 4 week period and all performed the procedures in solitude. Both groups of subjects increased performance levels (time and accuracy) over the four weeks, but improvement was significantly greater for the practicing subjects. After eight sessions, convergence of performance levels was observed, but plateauing of performance levels was not evident, even with the simple paradigms evaluated. To investigate what factors contribute to learning, subjects were assessed with respect to their surgical experiences, personality, and self-evaluated motor skills. Subjects with prior endoscopic surgical experience, interest in mechanical activities (as measured by the Strong Interest Inventory), or regular engagement in video game play tended to be more skillful initially, but demonstrated less improvement in performance levels after practice than subjects who had lower levels of experience, interest, or video game play. Manual dexterity (as measured by the Purdue Pegboard Manual Dexterity Test) was positively related to the degree of observed improvement. We conclude that "inanimate" videoendoscopic paradigms offer relatively inexpensive and useful training exercises for acquiring basic eye-hand coordination skills. Relevance for animate laboratory skills requirements are probable but can only be inferred. Subjects with manual dexterity skills used in video games may perform better initially in the inanimate videoendoscopic situation but this advantage is shortlived.

Carbon dioxide pneumoamnios causes acidosis in fetal lamb.

Recently developed techniques of video-endoscopic surgery may offer new hope for the future of fetal surgery. To allow this approach, the amniotic cavity has to be temporarily enlarged, either by carbon dioxide (CO2) insufflation or by amnioinfusion. In 6 anesthetized ewes, CO2 insufflation of the amniotic cavity produced severe fetal hypercapnia (from 57.6 +/- 1.6 to 87.0 +/- 7.0 torr) and acidosis (from 7.22 +/- 0.03 to 7.11 +/- 0.08) despite normal maternal CO2 pressure and pH. CO2 pneumoamnios does not therefore appear to be an ideal working medium. Fetal endoscopic surgery through amnioinfusion of physiologic fluid may be a safer alternative.

Endoscopic retrograde cholangiography and laparoscopic cholecystectomy: stones, stents and sphincterotomy

Endoscopic retrograde cholangiopancreatography (ERCP) is clearly a useful adjunct in the management of patients undergoing laparoscopic cholecystectomy who have common bile duct stones. Whether endoscopic sphincterotomy plus laparoscopic cholecystectomy is superior to traditional open cholecystectomy and bile duct exploration is a question which remains to be answered by prospective, randomized trials. The immense popularity of laparoscopic cholecystectomy may prohibit such a study in the USA. In expert hands, endoscopic stone extraction is usually successful, so ERCP can be deferred until after cholecystectomy unless there is serious suspicion of a duct stone preoperatively. Actual clinical practice will depend, however, on the skill of the surgeon, the skill of the endoscopist, and the commitment to removing the gallbladder laparoscopically. It would seem prudent for surgeons to continue to direct their energy toward conquering the common bile duct via the laparoscope, and leave ERCP and stone extraction in the realm of the endoscopist who has been extensively trained in this difficult technique. Proficiency at ERCP, sphincterotomy and stone extraction requires considerable training, and the procedure should not be attempted by individuals who have performed fewer than 100 ERCPs and 25 individually supervised sphincterotomies, according to the ASGE Standards of Training 1992. As experience with video endoscopic surgery increases and technology improves, it will become possible to remove most duct stones at the time of cholecystectomy, thus obviating the need for endoscopic sphincterotomy. In addition, ERCP should be regarded as the treatment of choice for postoperative cystic duct stump leaks. Studies have shown that any type of biliary decompression, i.e. sphincterotomy, stents or nasobiliary catheters, will be successful. The authors recommend that, in the absence of duct stones, stenting or nasobiliary catheters be used as they are less invasive. Bile duct leaks may also be managed endoscopically, but success depends on the individual characteristics of the duct injury. The decision to manage late onset strictures endoscopically should be individualized, and consideration of local endoscopic expertise, operative risk, interval between surgery and stricture, and the patient's wishes should be made.

Clinical Experience with Minimally Invasive Thoracic Surgery

From October 1991 to June 1992 video-endoscopic lung surgery was applied in a total of 109 patients. In the first case a pulmonary cyst measuring 15 x 18 cm was resected. In 21 patients lung nodules were exstirpated by means of wedge resection. Moreover, metastasectomies, open lung biopsies, parietal pleurectomies, resections of bullae, and decortications, as well as 3 lower-lobe lobectomies were performed using video-endoscopic procedures. Closure of lung parenchyma was carried out using the 3 cm Endo-GIA stapler (Autosuture). In none of the patients were we forced to enlarge the intervention to a thoracotomy because of technical problems. Indications, operative technique and results are presented. This new technique offers all the known advantages of minimally invasive surgery to patients requiring thoracic surgery.

Laser endoscopic sympathectomy for palmar hyperhidrosis.

Hyperhidrosis palmaris is a common disorder among the Orientals. Despite numerous therapeutic modalities in practice, none has proved entirely satisfactory. With the introduction of video-endoscopic surgery, we combined this system with a fiber optic Nd-YAG laser unit, electrocautery, and a laser Doppler flowmeter to design a new and promising therapeutic technique for palmar hyperhidrosis. General anesthesia with alternating one-lung ventilation is essential for a safe and smooth endoscopic sympathectomy. An operating endoscope was introduced into thoracic cavity via the second intercostal space and then attached to a CCD camera video system, which provided clear visibility of the sympathetic trunk in most cases. The proper level of the sympathetic trunk was further confirmed with the aid of vasomotor response of the palmar skin resulting from electric stimulation on the related sympathetic trunk. Finally, the confirmed target was precisely vaporized with a low power Nd-YAG laser through an endoscope. Twenty patients underwent bilateral sympathectomy, mostly on T2 and its adjacent trunk. This technique did not cause any injury to the lung or bleeding. No Horner's syndrome was produced. It provided a precise ganglionectomy on a confirmed target under clear magnified vision. Consequently, a definite and long-lasting therapeutic effect seemed warranted. It was considered to be a relative minor and safe procedure causing minimal discomfort and an almost invisible scar without producing serious complications. It also shortened the operation time and hospital stay remarkably in comparison with other open sympathectomy procedures.

Videoendoscopic laser surgery in horses

Videoendoscopic laser surgery in horses