Entry techniques in gynecologic laparoscopy—a review
© Springer-Verlag 2011
Received: 9 June 2011
Accepted: 19 October 2011
Published: 13 November 2011
Laparoscopy is one of the most common surgical procedures in gynecologic medicine. Major complications associated with gynecologic laparoscopy are relatively rare, with up to 50% related to laparoscopic entry. Several entry techniques have been developed, all of which aim to provide a safe and easy entry to the abdominal cavity. In this article, we aim to review the available evidence on laparoscopic entry techniques in gynecologic surgery. We found no evidence that the Hasson (open) technique is superior to the Veress needle entry, the preferred method of most gynecologists all over the world. When entering the abdomen using the Veress needle, an intraperitoneal pressure <10 mmHg is a reliable predictor of correct intraperitoneal placement. Entry at Palmer’s point (left upper quadrant laparoscopy) is recommended for patients with suspected or known periumbilical adhesions, or a history or presence of umbilical hernia, or after three failed insufflation attempts at the umbilicus. Recently published trials suggest that direct trocar entry, especially when using optical trocar systems, might be superior to both the Hasson open technique and the Veress needle entry to avoid extraperitoneal insufflation and failed entry. Moreover, blood loss can be reduced and the mean entry time shortened. Laparoscopic entry techniques are still a controversial topic in gynecologic surgery. Many studies are underpowered in order to assess the risk for rare but life-threatening complications. In conclusion, there is no solid evidence proving the superiority of any method of laparoscopic entry.
KeywordsLaparoscopy Entry techniques Gynecology Complications Veress needle Hasson technique Direct trocar entry
Laparoscopy is one of the most common surgical procedures in gynecologic medicine and has become the method of choice over the last few decades for treating benign diseases that require surgery [1, 2]. Major complications from gynecologic laparoscopy are relatively rare, occurring in three to six per 1,000 cases. However, complications related to access represent one third to one half of these adverse events [1, 3]. These complications include serious and potentially life-threatening adverse events in about 0.4 of 1,000 laparoscopic procedures, such as perforation of the bowel, major abdominal vessels, and vessels of the anterior abdominal wall. These factors make the access phase the most critical step of a laparoscopic procedure. Less serious complications include postoperative infection, extraperitoneal insufflations, and subcutaneous emphysema .
In a large survey of 506 patients with entry access injuries, gynecologic procedures accounted for 63% of claims outside the USA and for at least 47% of all cases. The structures injured most frequently during primary entry access were the small bowel, the iliac artery, and the colon, together accounting for more than 50% of injuries . These data present a more severe spectrum of injuries than those described in procedure-based studies and underline the severity and possible lethality of entry access injuries.
Several entry techniques exist [6–8]. However, there is no clear consensus on the optimal method of entry to the peritoneal cavity [8, 9]. Even a recent Cochrane database systematic review showed no evidence of benefit with regard to the safety of one technique over another . We aimed to review the available evidence on laparoscopic entry techniques.
A computerized search of the medical literature was conducted with the MedLine database. Articles published up until February 2011 were searched for the keywords laparoscopy, laparoscopic entry, Veress needle, Hasson technique, open trocar entry, complications, and adverse events. The selected articles’ bibliographies were also manually examined for any articles not captured by the computerized search. Case reports, abstracts, and letters were excluded. Randomized, quasi-randomized, and nonrandomized, or cohort, studies on human patients were included if they compared access methods and provided relevant information on safety and efficacy outcome that had to be defined a priori.
Challenges during laparoscopic entry
Adhesions at the umbilical area are a major concern with regard to the safety of laparoscopic entry. Rates of up to 21% and 28% have been reported for women with previous laparoscopy and previous laparotomy, respectively [10, 11]. Patients with prior midline incisions, in particular, are at high risk (up to 42%) . Entry techniques other than the classic CO2 insufflation using a subumbilical Veress needle might be useful in these patients.
In very thin patients, especially in those with an android pelvis or a prominent sacral promontory, the great vessels have been reported to lie about 1 to 2 cm underneath the umbilicus [13, 14]. In obese patients, the umbilicus is shifted caudally toward the aortic bifurcation . These patients are believed to be at an increased risk for major vessel injury during the course of a closed laparoscopic entry .
The Veress needle
Overview of different entry techniques
First published in
Rates of major visceral injury (%)
Rates of major vascular injury (%)
Veress needle entry (classic)
Gastroenterologia, 1961 
Optical Veress needle (minilaparoscopy)
Endosc Surg Allied Technol, 1995 
Pressure sensor-equipped Veress needle
J Am Assoc Gynecol Laparosc, 1994 
Hasson technique (open entry)
Am J Obstet Gynecol, 1971 
Direct trocar entry
Obstet Gynecol, 1983 
Alternative Veress needle insertion sites
Alternative sites for Veress needle insertion have been reported: Insertion in the left upper quadrant (LUQ, Palmer’s point) has been mentioned to be useful in obese and very thin patients, as well as in those with a history of previous open abdominal surgery. In the presence of a large uterine or pelvic mass, it may be also advantageous . The Veress needle is inserted 3 cm below the left subcostal border in the midclavicular line . The method should not be applied in patients with previous splenic or gastric surgery, portal hypertension, hepatosplenomegaly, and gastropancreatic masses . Laparoscopic entry using Palmer’s point has been reported to be safe and effective, with a low failure rate of about 1.5%. Complications, mainly puncture of the left lobe of the liver, have been found in about 1% of cases [19, 22, 23].
Insertion of the Veress needle directly through the ninth or tenth intercostal space, at the anterior axillary line along the superior surface of the lower rib, has also been reported to be safe. A retrospective analysis of more than 900 cases of pneumoperitonization through the ninth intercostal space revealed only two major complications directly related to the laparoscopic entry . The same indications apply to this method as to the entry at the Palmer’s point .
Last but not the least, one might insufflate CO2 through the posterior vaginal fornix (“trans cul-de-sac insufflation”) or transvaginally through the fundus of the uterus. Both methods are indicated in extremely obese women [25–32]. For the transuterine route, there was a lower ratio between punctures and establishment of a pneumoperitoneum, when prospectively compared to the classical intraumbilical approach in obese women with a BMI >25 kg/m2 .
Additional considerations with the Veress needle entry
The following tests that attempt to determine the correct intra-abdominal placement of the Veress needle have been described: the double click sound of the Veress needle; the Palmer’s test (aspiration test); the hanging drop of saline test ; the “hiss” sound test ; the syringe test [35–38]; and the pressure profile test, of which the first five pressures registered by the gas insufflator are recorded at 5-s intervals and pressures less than 10 mmHg are assumed to indicate correct intraperitoneal placement [17, 39]. A prospective analysis demonstrated that the double click, aspiration, and hanging drop tests provided very little useful information about the placement of the Veress needle . These findings are supported by the fact that, despite the implementing of these tools in the clinical routine, serious complications occur. Especially in women with previous open abdominal surgery, the pressure profile test is more specific and sensitive than the Palmer’s test . However, performing the Palmer’s test is still recommended because of its value in warning the surgeon if any blood or feces is aspirated.
Many gynecologists elevate the anterior lower abdominal wall at the time of the Veress needle insertion either by hand or with the use of towel clips . However, only with the use of towel clips a sufficient elevation of about 7 cm above the level of the viscera can be achieved . Moreover, by lifting the abdominal wall by hand, one might also elevate the omentum in rare cases, causing omental perforations . However, in a recent Cochrane database analysis, the authors concluded that lifting the abdominal wall resulted in an increased rate of entry failure (odds ratio 5.17) without an increase in the complication rate .
The literature reports successful Veress needle entry into the abdominal cavity on the first attempt in about 85% of cases. This is of particular importance since higher numbers of attempts are associated with increased complication rates including extraperitoneal insufflation, omental injuries, bowel injuries, and failed laparoscopy [41, 43].
The optical Veress needle
Entry using the optical Veress needle is also called “minilaparoscopy.” A modified Veress needle of 2.1 mm diameter and a 10.5-cm-long cannula are used, allowing insertion of a thin, zero-degree, semirigid, fiberoptic minilaparoscope. During insertion of the Veress cannula with the telescope, one observes a cascade of color sequences on the monitor that represent the different abdominal wall layers. No randomized trials have been published as yet. Therefore, the relative risks of this procedure remain unclear . However, in a prospective study of 184 cases, two bowel perforations occurred (Table 1) .
As another modification of the classical Veress needle, a pressure sensor-equipped Veress needle has been described . However, no further studies evaluating the risk profile of this method have been published to date. It would be reasonable to conclude that these Veress needle modifications have not proven themselves in practice.
Insertion of the camera trocar after establishment of the pneumoperitoneum
Pneumoperitonization using the Veress needle is followed by trocar insertion. The force applied to the anterior abdominal wall during this procedure might put the viscera at risk for damage.
An adequate pneumoperitoneum is considered useful to prevent visceral damage during trocar insertion. Traditionally, the pneumoperitoneum has been defined as sufficient after insufflation of 1 to 4 L of CO2 or the establishment of an intraperitoneal pressure of 10 to 15 mmHg . It has been demonstrated that the use of the “pressure technique,” using a median pressure of 14 mmHg, leads to a reduction in the complication rate of 50% when compared to the “volume technique” .
Based on these considerations, one might consider the pressure-controlled “high-pressure entry” (HIP entry) technique of benefit in order to decrease the complication rate.Three prospective studies on the safety of HIP entry using median intra-abdominal pressure values of 25–30 mmHg included nearly 9,000 female subjects. Only four bowel injuries (0.04%) and one major vessel injury (0.01%) were reported. Although the method leads to a significant decline in pulmonary compliance of about 20%, the maximum respiratory effects at 25 to 30 mmHg did not differ from the effect of the Trendelenburg position with intra-abdominal pressures of 15 mmHg [2, 44, 47, 48].
In order to minimize the risk for entry-associated complications following Veress needle insufflation, disposable shielded trocars and optical access trocars have been developed. Disposable shielded trocars are designed with a shield that partially retracts, exposing the sharp tip as it encounters resistance through the abdominal wall. After the shield enters the abdominal cavity, it springs forward and covers the sharp tip of the trocar . The rationale for this method is to avoid intra-abdominal injuries. However, evidence proves that major complications, including death from trocar entry, cannot be avoided by using disposable shielded trocars [49, 50]. There is a lack of evidence in the literature about the safety of these instruments when used after establishment of the pneumoperitoneum.
There are two available disposable visual entry systems: the Endopath Optiview optical trocar (Ethicon Endo-Surgery, Inc., Cincinnati, OH) and the Visiport optical trocar (Tyco-United States Surgical, Norwalk, CT). Both are inserted through a 5-mm incision in the anterior rectus fascia after having withdrawn the Veress needle and dissected off the fatty tissue. However, with regard to trocar entry after pneumoperitonization by the Veress needle, most reports did not show superiority of visual entry trocars over other trocars, based on entry-associated complications, since these trocars cannot avoid vascular or visceral injury [44, 51–53]. Only in one retrospective study, the rate of major complications during insertion of the primary trocar in the blind insertion group was five of 1,000 (0.5%), whereas there were no major complications in the optical-guided insertion group (0.0%) .
Another visual entry system is the EndoTIP visual cannula (ENDOTIP; Karl Storz, Tuttlingen, Germany). The cannula has no cutting or sharp end. Thus, tissue layers are not transsected . However, there are no randomized trials that compare this entry method to any other method.
Radially expanding access system
The radially expanding access system (Step; InnerDyne, Sunnyvale, CA) consists of a 1.9-mm Veress surrounded by an expanding polymeric sleeve. The abdomen can be insufflated prior to removal of the Veress needle and subsequent dilatation of the sleeve by inserting a blunt obturator with a twisting motion [56–58]. The advantages of this system arise from the elimination of sharp trocars [44, 56]. In a number of case series and randomized trials, there were no major vessel injuries and no procedure-related deaths . Randomized controlled trials have demonstrated less postoperative pain and more patient satisfaction with the radially expanding device than with the conventional trocar entry techniques [59–62].
Hasson technique (open laparoscopic entry)
Hasson first described his technique of open access to the peritoneal cavity in 1971 (Table 1) . He suggested that the method might result in less adverse events, such as gas embolism, preperitoneal insufflation, visceral and major vascular injury, and that it thus might be superior to the blinded entry. Thus, it has been recommended for patients with previous abdominal surgery, especially for those with longitudinal abdominal wall incisions.
In their large 2002 meta-analysis on laparoscopic entry techniques, Molloy et al. reported a rate of 0.1% bowel injuries and 0.005% major vascular injuries for the Hasson technique out of a total of 21,547 procedures, with the vast majority of reviewed studies providing only level III evidence . However, several case reports of vascular injuries with the open technique have been published [5, 65, 66].
The Veress needle vs. the Hasson open technique
Many studies have been conducted comparing the safety of the Hasson technique vs. entry using the Veress needle. Hasson himself conducted a review that included 17 publications of open laparoscopy (20,691 patients), comparing them to studies of closed laparoscopy (669,662 patients). This detailed analysis revealed an interesting result: General surgeons had experienced higher complication rates than gynecologists with the closed technique, whereas gynecologists had reported similar complication rates with both techniques .
Several other reviews of studies comparing open and closed entry techniques have been published. Bonjer et al. reviewed 12 trials on laparoscopy in general surgery (6 about the closed and 6 about the open technique, including 489,335 and 12,444 patients, respectively). The rates of visceral and vascular injury were, respectively, 0.08% and 0.07% after closed laparoscopy, and 0.05% and 0% after open laparoscopy (p = 0.002). Mortality rates did not differ significantly . Similar findings in general surgery were reported by Sigman et al.  and Zaraca et al. .
However, other studies did not report any significant differences, in terms of major complication rates, between the Veress needle entry and the Hasson technique. The Swiss Association for Laparoscopic and Thoracoscopic Surgery prospectively collected data on 14,243 low-risk patients undergoing standard laparoscopy between 1995 and 1997. Only eight visceral injuries (0.06%) after primary port insertion were found (six after blind insertion vs. two after a Hasson entry; not significant) . However, in a meta-analysis of a mixed study population including gynecologic and general surgical trials, the risk of bowel injury was higher with open access compared to needle/trocar access (relative risk = 2.17). However, the authors noted that selection bias may have influenced the results: open procedures may be more likely chosen for patients with previous abdominal surgery. On the other side, in nonobese patients, a 57% reduced risk of minor complications was seen with open access (relative risk = 0.43).Considering serious adverse events secondary to gas insufflation, open laparoscopy seems superior to the closed entry. The rate of carbon dioxide embolism was 0.001% in a review of 489,335 closed laparoscopies . Several case reports have reported coronary, cerebral, or other gas embolism with fatal or near fatal outcomes [67, 72]. Such complications have not been reported at open laparoscopy.
The evidence does not provide a definitive answer to the question of whether the open technique is superior or inferior to the Veress needle entry. One might also consider other Veress needle insertion sites, such as the Palmer’s point, more appropriate than the Hasson entry in high-risk patients with obesity or previous abdominal surgery.
Laparoendoscopic single-site surgery/single-incision laparoscopic surgery
Laparoendoscopic single-site surgery (LESS) is a novel and rapidly advancing minimally invasive technique, developed to result in improved cosmesis for patients and even decreased postoperative analgesia requirements when compared to conventional laparoscopy . The access point for these surgeries is typically the umbilicus . There are various multiaccess single-port systems provided by various manufacturers. The open Hasson entry is used to install these subumbilical access systems. Comparisons between the single-incision approach and conventional multipuncture procedures have demonstrated similar complication rates. However, the sample sizes were too small to draw valid conclusions about the safety profile of LESS in gynecologic studies.
Direct trocar entry
This technique was developed to reduce or avoid various complications related to the Veress needle use, such as a failed pneumoperitoneum, preperitoneal insufflation, intestinal insufflation, or the more serious CO2 embolism . Moreover, it is faster than any other method of laparoscopic entry [74, 75]. Recently, a large prospective study that included 17,350 patients undergoing gynecologic laparoscopy in China using the "Yan’s open technique" was published. Laparoscopic entry was performed by making an umbilical incision with a scalpel followed by direct entry of a 10-mm trocar into the abdominal cavity through direct trocar puncture or insertion of the cannula sheath via the opened umbilicus. As a control group, 4,570 patients were enrolled, who were undergoing the traditional Veress needle entry. The use of the Veress needle was associated with a significantly higher complication rate (0.09% vs. 0.01%) .
Several randomized controlled trials, comparing direct trocar access to the Veress needle, have been published, most of them demonstrating lower minor complication rates and/or a shorter entry time. The largest trial (n = 1,000) was published by Zakherah, which showed a significantly lower minor complication rate for the direct trocar access (0.4% vs. 14%, p < 0.0001) . Agresta et al. compared direct trocar insertion to the Veress needle access in nearly 600 patients. Obesity, major abdominal distension, and two or more previous abdominal operations were the exclusion criteria. There were no minor complications in the direct access group, in contrast to a rate of 5.9% in the Veress needle group (p < 0.01) . Similar results concerning the rate of minor complications were reported by Nezhat et al., who excluded past abdominal surgery but took into account BMI, and by Byron et al. [74, 78]. A study by Altun et al. showed higher rates for both major and minor complications in the Veress needle group, which, however, were not significant due to the small sample size .
Direct access can also be performed using optical access trocars to achieve visual guidance during direct entry. Only a few randomized trials prospectively evaluated the risk profile of direct optical access and compared it to other entry techniques.
Two trials compared the direct optical access to the Veress needle technique [80, 81]. The first study was performed in postmenopausal women. Estrogen loss at menopause is known to have a profound influence on skin, with postmenopausal atrophy and loss of tone and elasticity. The study demonstrated significantly lower entry time (65.7 ± 11.9 vs. 192.8 ± 5.6 s) and lower overall blood loss in the direct optical access group (9.6 ± 8.1 19.2 ± 7.3 ml) . Similar results were found, in premenopausal women, by the same group of investigators. Direct optical access led to a shorter entry time . When comparing the direct optical access to the Hasson technique, there was lower blood loss (9.6 ± 8.1 vs. 19.2 ± 7.3 ml) and a shorter mean entry time (61.8 ± 10.4 vs. 163.1 ± 9.2 s) . Based on these results, the direct optical access can be considered a feasible and safe alternative for first laparoscopic entry in both pre- and postmenopausal women.
One recent prospective study evaluated direct primary visual entry using the EndoTIP visual cannula (ENDOTIP; Karl Storz) in 165 urologic patients . Access to the peritoneum with the EndoTIP was successful in all consecutive transperitoneal cases. No complications were registered. The method seems feasible and safe in a gynecologic patient collective. Direct optical access has also been mentioned as a possible future entry technique at Palmer’s point when adhesions are suspected .
Several study weaknesses have to be considered when drawing conclusions from the reported results. First and foremost, surgeons might be experienced in either one of the techniques—this issue has not been properly assessed in most of the studies. Thus, learning curves must be taken into account when surgeons are recommended to start using a technique that has been considered superior in studies. The existence of learning curves for laparoscopic entry techniques has already been proven, and the incidence of related complications is higher among inexperienced surgeons. Surgeons might experience fewer adverse events if they use the technique with which they are most familiar [85–87]. This might also be considered when recommending alternative Veress needle entry sites in obese patients or women with previous abdominal surgery. The use of alternative Veress insertion sites by gynecologists is limited as is the literature on this issue.
Furthermore, only very few studies have evaluated the safety profile of alternative entry techniques including the optical Veress needle and the radially expanding access system. Thus, the incidences of rare but possibly life-threatening complications can hardly be assessed for these procedures. The same is true for direct trocar access. However, more prospective randomized studies will hopefully be published in the near future providing a reliable overview on the technique’s safety profile. Whether LESS procedures might be widely accepted will depend on other outcome parameters than just an improved cosmesis: reduced pain, perioperative morbidity, and convalescence could justify both the increased technical demands and the increased costs .
Literature on cosmetic considerations is also scarce. To the best of our knowledge, only one study has directly addressed this issue. This trial dealt with the general population’s view on the aesthetic importance of the umbilicus with regard to single-incision techniques . From that point of view, one might consider direct trocar entry using 5-mm trocars superior to the Hasson technique. Keeping in mind that most of the entry techniques are similar in terms of major complication rates, future research might also want to focus on the cosmetic aspects of these techniques.
All in all, there is no solid evidence proving the superiority of any method of laparoscopic entry. In general, the guidelines set forth by the Society of Obstetricians and Gynecoogists of Canada in 2007  remain valid. Among other recommendations, we chose to underline the following: in gynecologic procedures, there is no evidence that the Hasson technique is superior to the Veress needle entry. When entering the abdomen using the Veress needle, an intraperitoneal pressure <10 mmHg is a reliable predictor of correct intraperitoneal placement. Entry at the Palmer’s point (LUQ laparoscopy) is recommended in patients with suspected or known periumbilical adhesions or a history or presence of umbilical hernia, or after three failed insufflation attempts at the umbilicus.
However, recently published trials suggest that direct trocar entry, especially when using optical trocar systems, might be superior to both the Hasson open technique and the Veress needle entry in terms of avoiding extraperitoneal insufflation and failed entry. Moreover, blood loss can be reduced and the mean entry time shortened.
Much work has been done in order to make laparoscopy a safe procedure. However, further investigation is needed in order to shed some new light into the “hot topics” of laparoscopic entry. Will there be hard evidence for a certain technique on how to deal with obese patients or suspected anterior wall adhesions? Will any new strategies be developed in order to avoid major complications, such as major vessel or bowel injury? Hopefully, researchers will be able to clarify these and other concerns in the future. Notably, cosmetic results have not been considered in the literature as yet and might also be a focus of interest in the near future for the older Veress needle and the Hasson entry techniques.
Declaration of interest
The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
- Makai G, Isaacson K (2009) Complications of gynecologic laparoscopy. Clin Obstet Gynecol 52:401–411PubMedView ArticleGoogle Scholar
- Garry R (1999) Towards evidence based laparoscopic entry techniques: clinical problems and dilemmas. Gynaecol Endosc 8:315–326View ArticleGoogle Scholar
- Jansen FW, Kolkman W, Bakkum EA, de Kroon CD, Trimbos-Kemper TC, Trimbos JB (2004) Complications of laparoscopy: an inquiry about closed- versus open-entry technique. Am J Obstet Gynecol 190:634–638PubMedView ArticleGoogle Scholar
- Varma R, Gupta JK (2008) Laparoscopic entry techniques: clinical guideline, national survey, and medicolegal ramifications. Surg Endosc 22:2686–2697PubMedView ArticleGoogle Scholar
- Chandler JG, Corson SL, Way LW (2001) Three spectra of laparoscopic entry access injury. J Am Coll Surg 192:478–491PubMedView ArticleGoogle Scholar
- Tinelli A, Malvasi A, Schneider AJ, Keckstein J, Hudelist G, Barbic M, Casciaro S, Giorda G, Tinelli R, Perrone A, Tinelli FG (2006) First abdominal access in gynaecological laparoscopy: which method to utilize? Minerva Ginecol 58:429–440PubMedGoogle Scholar
- Agresta F, De Simone P, Ciardo LF, Bedin N (2004) Direct trocar insertion vs Veress needle in nonobese patients undergoing laparoscopic procedures: a randomized prospective single-center study. Surg Endosc 18:1778–1781PubMedView ArticleGoogle Scholar
- Merlin TL, Hiller JE, Maddern GJ, Jamieson GG, Brown AR, Kolbe A (2003) Systematic review of the safety and effectiveness of methods used to establish pneumoperitoneum in laparoscopic surgery. Br J Surg 90:668–679PubMedView ArticleGoogle Scholar
- Ahmad G, Duffy JM, Phillips K, Watson A (2008) Laparoscopic entry techniques. Cochrane Database Syst Rev 16(2):CD006583Google Scholar
- Sepilian V, Ku L, Wong H, Liu CY, Phelps JY (2007) Prevalence of infraumbilical adhesions in women with previous laparoscopy. JSLS 11:41–44PubMedGoogle Scholar
- Vilos AG, Vilos GA, Abu-Rafea B, Hollett-Caines J, Al-Omran M (2006) Effect of body habitus and parity on the initial Veres intraperitoneal CO2 insufflation pressure during laparoscopic access in women. J Minim Invasive Gynecol 13:108–113PubMedView ArticleGoogle Scholar
- Audebert AJ, Gomel V (2000) Role of microlaparoscopy in the diagnosis of peritoneal and visceral adhesions and in the prevention of bowel injury associated with blind trocar insertion. Fertil Steril 73:63163–63165View ArticleGoogle Scholar
- Hurd WW, Bude RO, DeLancey JO, Pearl ML (1992) The relationship of the umbilicus to the aortic bifurcation: implications for laparoscopic technique. Obstet Gynecol 80:48–51PubMedGoogle Scholar
- Nezhat F, Brill AI, Nezhat CH, Nezhat A, Seidman DS, Nezhat C (1998) Laparoscopic appraisal of the anatomic relationship of the umbilicus to the aortic bifurcation. J Am Assoc Gynecol Laparosc 5:135–140PubMedView ArticleGoogle Scholar
- Hurd WW, Bude RD, De Lancey JOL, Gavin JM, Aisen AM (1991) Abdominal wall characterization with magnetic resonance imaging and computed tomography: the effect of obesity in the laparoscopic approach. J Reprod Med 26:473–476Google Scholar
- McIlwaine K, Cameron M, Readman E, Manwaring J, Maher P (2011) The effect of patient body mass index on surgical difficulty in gynaecological laparoscopy. Gynaecol Surg 8:145–149View ArticleGoogle Scholar
- Azevedo JL, Azevedo OC, Miyahira SA, Miguel GP, Becker OM Jr, Hypólito OH, Machado AC, Cardia W, Yamaguchi GA, Godinho L, Freire D, Almeida CE, Moreira CH, Freire DF (2009) Injuries caused by Veress needle insertion for creation of pneumoperitoneum: a systematic literature review. Surg Endosc 23:1428–1432PubMedView ArticleGoogle Scholar
- Perissat J, Vitale GC (1991) Laparoscopic cholecystectomy: gateway to the future. Am J Surg 161:408PubMedView ArticleGoogle Scholar
- Granata M, Tsimpanakos I, Moeity F, Magos A (2010) Are we underutilizing Palmer’s point entry in gynecologic laparoscopy? Fertil Steril 94:2716–2719PubMedView ArticleGoogle Scholar
- Palmer R (1974) Safety in laparoscopy. J Reprod Med 13:1–5PubMedGoogle Scholar
- Tulikangas PK, Nicklas A, Falcone T, Price LL (2000) Anatomy of the left upper quadrant for cannula insertion. J Am Assoc Gynecol Laparosc 7:211–214PubMedView ArticleGoogle Scholar
- Tulikangas PK, Robinson DS, Falcone T (2003) Left upper quadrant cannula insertion. Fertil Steril 79:411–412PubMedView ArticleGoogle Scholar
- McDanald DM, Levine RL, Pasic R (2005) Left upper quadrant entry during gynecologic laparoscopy. Surg Laparosc Endosc Percutan Tech 15:325–327PubMedView ArticleGoogle Scholar
- Agarwala N, Liu CY (2005) Safe entry technique during laparoscopy: left upper quadrant entry using the ninth intercostal space: a review of 918 procedures. J Minim Invasive Gynecol 12:55–61PubMedView ArticleGoogle Scholar
- Sanders RR, Filshie GM (1994) Transfundal induction of pneumoperitoneum prior to laparoscopy. J Obstet Gynaecol Br Cmwlth 107:316–317Google Scholar
- Morgan HR (1979) Laparoscopy: induction of pneumoperitoneum via transfundal puncture. Obstet Gynecol 54:260–261PubMedGoogle Scholar
- Wolfe WM, Pasic R (1990) Transuterine insertion of Veress needle in laparoscopy. Obstet Gynecol 75:456–557PubMedGoogle Scholar
- Trivedi AN, MacLean NE (1994) Transuterine insertion of Veress needle for gynecological laparoscopy at Southland Hospital. NZ Med J 107:316–317Google Scholar
- Pasic R, Levine RL, Wolfe WM Jr (1999) Laparoscopy in morbidly obese patients. J Am Assoc Gynecol 6:307–312View ArticleGoogle Scholar
- Santala M, Jarvela I, Kauppila A (1999) Transfundal insertion of a Veress needle in laparoscopy of obese subjects: a practical alternative. Hum Reprod 14:2277–2278PubMedView ArticleGoogle Scholar
- Neely MR, McWilliams R, Makhlouf HA (1975) Laparoscopy: routine pneumoperitoneum via the posterior fornix. Obstet Gynecol 45:459–460PubMedGoogle Scholar
- van Lith DA, van Schie KJ, Beekhuizen W, du Plessis M (1980) Cul-de-sac insufflation: an easy alternative route for safely inducing pneumoperitoneum. Int J Gynaecol Obstet 17:375–378PubMedGoogle Scholar
- Fear RE (1968) Laparoscopy: a valuable aid in gynecologic diagnosis. Obstet Gynecol 31:297–309PubMedView ArticleGoogle Scholar
- Lacey CG (1976) Laparoscopy: a clinical sign for intraperitoneal needle placement. Obstet Gynecol 47:625–627PubMedGoogle Scholar
- Rosen DM, Lam AM, Chapman M, Carlton M, Cario GM (1998) Methods of creating pneumoperitoneum: a review of techniques and complications. Obstet Gynecol Surv 53:167–174PubMedView ArticleGoogle Scholar
- Brill AJ, Cohen BM (2003) Fundamentals of peritoneal access. J Am Assoc Gynecol Laparosc 10:287–297View ArticleGoogle Scholar
- Marret H, Harchaoui Y, Chapron C, Lansac J, Pierre F (1998) Trocar injuries during laparoscopic gynaecological surgery. Report from the French Society of Gynecological Laparoscopy. Gynaecol Endosc 7:235–241View ArticleGoogle Scholar
- Semm K, Semm I (1999) Safe insertion of trocars and Veress needle using standard equipment and the 11 security steps. Gynaecol Endosc 8:339–347View ArticleGoogle Scholar
- Yoong W, Saxena S, Mittal M, Stavoulis A, Ogbodo E, Damodaram M (2010) The pressure profile test is more sensitive and specific than Palmer’s test in predicting correct placement of the Veress needle. Eur J Obstet Gynecol Reprod Biol 152:210–213PubMedView ArticleGoogle Scholar
- Teoh B, Sen R, Abbott J (2005) An evaluation of four tests used to ascertain Veress needle placement at closed laparoscopy. J Minim Invasive Gynecol 12:153–158PubMedView ArticleGoogle Scholar
- Roy GM, Bazzurini L, Solima E, Luciano AA (2001) Safe technique for laparoscopic entry into the abdominal cavity. J Am Assoc Gynecol Laparosc 8:519–528PubMedView ArticleGoogle Scholar
- Hill DJ, Maher PJ (1996) Direct cannula entry for laparoscopy. J Am Assoc Gynecol Laparosc 4:77–79PubMedView ArticleGoogle Scholar
- Richardson RF, Sutton CJG (1999) Complications of first entry: a prospective laparoscopic audit. Gynaecol Endosc 8:327–334View ArticleGoogle Scholar
- Vilos GA, Ternamian A, Dempster J, Laberge PY, The Society of Obstetricians and Gynaecologists of Canada (2007) Laparoscopic entry: a review of techniques, technologies, and complications. J Obstet Gynaecol Can 29:433–465PubMedGoogle Scholar
- Schaller G, Kuenkel M, Manegold BC (1995) The optical Veress needle—initial puncture with a minioptic. Endosc Surg Allied Technol 3:55–57PubMedGoogle Scholar
- Janicki TI (1994) The new sensor-equipped Veress needle. J Am Assoc Gynecol Laparosc 1:154–156PubMedView ArticleGoogle Scholar
- Phillips G, Garry R, Kumar C, Reich H (1999) How much gas is required for initial insufflation at laparoscopy? Gynaecol Endosc 8:369–374View ArticleGoogle Scholar
- Abu-Rafea B, Vilos GA, Vilos AG, Ahmad R, Hollett-Caines J (2005) High pressure laparoscopic entry does not adversely affect cardiopulmonary function in healthy women. J Minin Invasive Gynecol 12:475–479View ArticleGoogle Scholar
- Champault G, Cazacu F, Taffinder N (1996) Serious trocar accidents in laparoscopic surgery: a French survey of 103,852 operations. Surg Laparosc Endosc 6:367–370PubMedView ArticleGoogle Scholar
- Saville LE, Woods MS (1995) Laparoscopy and major retroperitoneal vascular injuries (MRVI). Surg Endosc 9:1096–1100PubMedView ArticleGoogle Scholar
- McKernan J, Finley C (2002) Experience with optical trocar in performing laparoscopic procedures. Surg Laparosc Endosc 12:96–99View ArticleGoogle Scholar
- Angelini L, Lirici M, Papaspyropoulos V, Sossi F (1997) Combination of subcutaneous abdominal wall retraction and optical trocar to minimize pneumoperitoneum-related effects and needle and trocar injuries in laparoscopic surgery. Surg Endosc 11:1006–1009PubMedView ArticleGoogle Scholar
- Visiport Optical Trocar information booklet (Internet). Norwalk CY: AutoSuture. http://www.autosuture.com/AutoSuture/pagebuilder.aspx?contentID=39263&topicID=31737&breadcrumbs=0:63659,30780:0,65365:0#. Accessed 4 April 2007
- Jirecek S, Dräger M, Leitich H, Nagele F, Wenzl R (2002) Direct visual or blind insertion of the primary trocar. Surg Endosc 16:626–629PubMedView ArticleGoogle Scholar
- Ternamian AM (2001) How to impove laparoscopic access safety: ENDOTIP. Min Invasive Ther Allied Technol 10:31–39View ArticleGoogle Scholar
- Turner DJ (1999) Making the case for the radially expanding access system. Gynaecol Endosc 8:391–395View ArticleGoogle Scholar
- Bhoyrul S, Mori T, Way LW (1995) A safer cannula design for laparoscopic surgery: results of a comparative study. Surg Endosc 9:227–229Google Scholar
- Turner DJ (1996) A new radially expanding access system for laparoscopic procedures versus conventional cannulas. J Am Assoc Gynecol Laparosc 3:609–615PubMedView ArticleGoogle Scholar
- Yim SF, Yuen PM (2001) Randomized double-masked comparison of radially expanding access device and conventional cutting tip trocar in laparoscopy. Obstet Gynecol 97:435–438PubMedView ArticleGoogle Scholar
- Lam TY, Lee SW, So HS, Kwok SP (2000) Radially expanding trocars: a less painful alternative for laparoscopic surgery. J Laparoendosc Adv Surg Tech A 19:269–273View ArticleGoogle Scholar
- Bhoyrul S, Payne J, Steffes B, Swanstrom L, Way LW (2000) A randomized prospective study of radially expanding trocars in laparoscopic surgery. J Gastrointest Surg 4:392–397PubMedView ArticleGoogle Scholar
- Feste JR, Bojahr B, Turner DJ (2000) Randomized trial comparing a radially expandable needle system with cutting trocars. J Soc Laparosc Endosc Surg 4:11–15Google Scholar
- Hasson HM (1971) A modified instrument and method for laparoscopy. Am J Obstet Gynecol 110:886–887PubMedGoogle Scholar
- Molloy D, Kalloo PD, Cooper M, Nguyen TV (2002) Laparoscopic entry: a literature review and analysis of techniques and complications of primary port entry. Aust N Z J Obstet Gynaecol 42:246–254PubMedView ArticleGoogle Scholar
- Vilos GA (2000) Litigation of laparoscopic major vessel injuries in Canada. J Am Assoc Gynecol Laparosc 7:503–509PubMedView ArticleGoogle Scholar
- Hanney RM, Carmalt HL, Merrett N, Tait N (1999) Use of the Hasson cannula producing major vascular injury at laparoscopy. Surg Endosc 13:1238–1240PubMedView ArticleGoogle Scholar
- Hasson HM (1999) Open laparoscopy as a method of access in laparoscopic surgery. Gynaecol Endosc 8:353–362View ArticleGoogle Scholar
- Bonjer HJ, Hazebroek EJ, Kazemier G, Giuffrida MC, Meijer WS, Lange JF (1997) Open versus closed establishment of pneumoperitoneum in laparoscopic surgery. Br J Surg 84:599–602PubMedView ArticleGoogle Scholar
- Sigman HH, Fried GM, Garzon J, Hinchey EJ, Wexler MJ, Meakins JL (1993) Risks of blind versus open approach to celiotomy for laparoscopic surgery. Surg Laparosc Endosc 3:296–299PubMedGoogle Scholar
- Zaraca F, Catarci M, Gosselti F, Mulieri G, Carboni M (1999) Routine use of open laparoscopy: 1,006 consecutive cases. J Laparoendosc Adv Surg Tech A 9:75–80PubMedView ArticleGoogle Scholar
- Schafer M, Lauper M, Krahenbuhl L (2001) Trocar and Veress needle injuries during laparoscopy. Surg Endosc 15:275–280PubMedView ArticleGoogle Scholar
- Neudecker J, Sauerland S, Nengebauer F, Bergamaschi R, Bonjer HJ, Cuschieri A (2002) The European Association for Surgery Clinical Practice Guideline on the pneumoperitoneum for laparoscopic surgery. Surg Endosc 16:1121–1143PubMedView ArticleGoogle Scholar
- Fader AN, Cohen S, Escobar PF, Gunderson C (2010) Laparoendoscopic single-site surgery in gynecology. Curr Opin Obstet Gynecol 22:331–338PubMedView ArticleGoogle Scholar
- Byron JW, Markenson G, Miyazawa K (1993) A randomized comparison of Veress needle and direct trocar insertion for laparoscopy. Surg Gynecol Obstet 177:259–262PubMedGoogle Scholar
- Borgatta L, Gruss L, Barad D, Kaali SG (1990) Direct trocar insertion vs Veress needle use for laparoscopic sterilization. J Reprod Med 35:891–894PubMedGoogle Scholar
- Liu HF, Chen X, Liu Y (2009) A multi-center study of a modified open trocar first-puncture approach in 17 350 patients for laparoscopic entry. Chin Med J (Engl) 122:2733–2736Google Scholar
- Zakherah MS (2010) Direct trocar versus Veress needle entry for laparoscopy: a randomized clinical trial. Gynecol Obstet Invest 69:260–263PubMedView ArticleGoogle Scholar
- Nezhat FR, Silfen SL, Evans D, Nezhat C (1991) Comparison of direct insertion of disposable and standard reusable laparoscopic trocars and previous pneumoperitoneum with Veress needle. Obstet Gynecol 78:148–150PubMedGoogle Scholar
- Altun H, Banli O, Kavlakoglu B, Kücükkayikci B, Kelesoglu C, Erez N (2007) Comparison between direct trocar and Veress needle insertion in laparoscopic cholecystectomy. J Laparoendosc Adv Surg Tech A 17:709–712PubMedView ArticleGoogle Scholar
- Tinelli A, Malvasi A, Guido M, Istre O, Keckstein J, Mettler L (2009) Initial laparoscopic access in postmenopausal women: a preliminary prospective study. Menopause 16:966–970PubMedView ArticleGoogle Scholar
- Tinelli A, Malvasi A, Istre O, Keckstein J, Stark M, Mettler L (2010) Abdominal access in gynaecological laparoscopy: a comparison between direct optical and blind closed access by Verres needle. Eur J Obstet Gynecol Reprod Biol 148:191–194PubMedView ArticleGoogle Scholar
- Tinelli A, Malvasi A, Hudelist G, Istre O, Keckstein J (2009) Abdominal access in gynaecologic laparoscopy: a comparison between direct optical and open access. J Laparoendosc Adv Surg Tech A 19:529–533PubMedView ArticleGoogle Scholar
- Hickey L, Rendon RA (2006) Safe and novel technique for peritoneal access in urologic laparoscopy without prior insufflation. J Endourol 20:622–626PubMedView ArticleGoogle Scholar
- Aust TR, Kayani SI, Rowlands DJ (2010) Direct optical entry through Palmer’s point: a new technique for those at risk of entry-related trauma at laparoscopy. Gynaecol Surg 7:315–317View ArticleGoogle Scholar
- Fader AN, Rojas-Espaillat L, Ibeanu O, Grumbine FC, Escobar PF (2010) Laparoendoscopic single-site surgery (LESS) in gynecology: a multi-institutional evaluation. Am J Obstet Gynecol 203:501.e1–501.e6View ArticleGoogle Scholar
- Lalchandi S, Phillips K (2005) Laparoscopic entry technique—a survey of practices of consultant gynaecologists. Gynaecol Surg 2:245–249View ArticleGoogle Scholar
- Burke C, Nathan E, Karthigasu K, Garry R, Hart R (2009) Laparoscopic entry—the experience of a range of gynaecological surgeons. Gynaecol Surg 6:125–133View ArticleGoogle Scholar
- Iranmanesh P, Morel P, Inan I, Hagen M (2011) Choosing the cosmetically superior laparoscopic access to the abdomen: the importance of the umbilicus. Surg Endosc 25(8):2578–2585PubMedView ArticleGoogle Scholar
- Veress J (1961) A needle for the safe use of pheumoperitoneum. Gastroenterologia 96:150–152PubMedView ArticleGoogle Scholar
- Copeland C, Wing R, Hulka JF (1983) Direct trocar insertion at laparoscopy: an evaluation. Obstet Gynecol 62:655–659PubMedGoogle Scholar