Currently, total splenectomy in small animals is most frequently performed via a ventral midline laparotomy. Frequent indications for total splenectomy include neoplasia, torsion of the splenic pedicle, splenomegaly as a result of infiltrative disease, and immune-mediated disease refractory to medical treatment.1,2 Laparoscopic splenectomy was first described in human patients in 19913 and is now the standard of care for patients requiring splenectomy.4–7 Benefits of minimally invasive splenectomy in human patients include decreased duration of hospitalization, decreased postoperative pain, earlier return to activity, improved cosmesis, and decreased complication rates when compared with open splenectomy.4–8 In human medicine, LS is considered best suited for patients with normal to moderately enlarged spleens.9–11 A study performed by Targarona et al11 found that 77% of patients with spleens weighing ≤ 3,200 g, as determined by means of 3-D CT volumetry, underwent a successful laparoscopic splenectomy but reported a > 75% rate of conversion to open laparotomy for patients with spleens weighing more than 3,200 up to 3,600 g. Laparoscopic splenectomy in human patients with a massively enlarged spleen (craniocaudal spleen length of 17 cm or a morcellated weight of > 600 g) has been reported to increase the risk of blood loss and is associated with longer surgery times and higher rates of conversion to an open procedure.9–11 On the basis of these results, an HALS technique was developed to facilitate a safer and less technically challenging procedure for removal of massively enlarged spleens in human patients, while retaining the benefits of a minimally invasive approach.12–15 To perform HALS, a Pfannestiel (horizontal suprapubic) or McBurnery (lower right anterior) incision is created to enable introduction of the surgeon's hand into the abdomen for relatively atraumatic intracorporeal manipulation of the spleen.13–15 This technique has been reported to allow for safe and comparatively less technically challenging intracorporeal splenectomy in human patients with massively enlarged spleens.13–15 Furthermore, it has been reported that HALS is associated with a shorter learning curve and similar operative times, blood loss, and complication rates, compared with LS.16,17 In patients with massively enlarged spleens, the likelihood of conversion to open splenectomy is lower for patients undergoing HALS versus LS.16–18
In veterinary medicine, laparoscopic surgery has gained tremendous popularity in recent years.19 As for human patients, dogs and cats20–22 treated with minimally invasive (vs open) surgical techniques may have reduced postoperative pain, a more rapid return to usual activities, and a reduction in the incidence of surgical site infections. Laparoscopic splenectomy has been reported in dogs23–26 and cats.27 In a study23 of 15 clinically normal dogs, the authors reported decreased postoperative pain, wound complications, and blood loss for dogs undergoing laparoscopic versus open splenectomy. However, in the same study, the mean surgical time for the LS group was significantly longer, compared with the mean surgical time for the open splenectomy group.23 In dogs, LS can present a technical challenge in some cases because the most common reason for total splenectomy is removal of splenic masses.1,2 Intracorporeal manipulation of a spleen containing a mass lesion during LS must be undertaken with caution and may result in major hemorrhage, requirement for conversion to open splenectomy, or both.27
Laparoscopic-assisted procedures reported in veterinary patients include ovariohysterectomy,28 intestinal surgeries, (biopsy, enterotomy, and resection and anastomosis),29–31 and gastropexy.32 To our knowledge, LAS has not been described in dogs. The objectives of the study reported here were to describe the technique for LAS in dogs and to report the perioperative outcome in a group of patients undergoing this procedure.
Materials and Methods
Case selection criteria and medical records review
Medical records of dogs undergoing LAS between 2012 and 2014 at 4 veterinary teaching hospitals were retrospectively reviewed. History, signalment, results of physical examination, results of preoperative diagnostic testing, details of surgical technique, intraoperative findings (including results of abdominal exploration and staging), concurrent surgical procedures, perioperative complications, histopathologic diagnoses, duration of postoperative hospitalization, and perioperative outcome were recorded. The perioperative period was defined as the time from admission to the hospital for LAS until the time of discharge, death, or euthanasia (within the same visit). Dogs were excluded from the study if medical records were considered incomplete.
Surgical technique: abdominal exploration and laparoscopic staging
Abdominal exploration and laparoscopic staging were performed in all cases with either a single-port or multiport technique. Single-port abdominal exploration and laparoscopic staging were performed as previously described by Case and Ellison.30 Two commercially available, multichannel, single-port platforms were used: a multichannel porta and a laparoscopic access device.b Briefly, following induction of general anesthesia, patients were positioned in dorsal recumbency and the ventral aspect of the abdomen was prepared for surgery according to standard aseptic technique. The multichannel port was inserted into the abdomen as previously described.30 An approximately 2.5-cm ventral midline incision was created immediately caudal to the umbilicus through the skin, subcutaneous tissues, and linea alba. Two apposing stay sutures were placed into the rectus sheath at the incision margins. Digital insertion through the incision was performed to liberate the falciform ligament. Two adjacently placed Carmalt forceps were attached to the multichannel port in a staggered manner allowing for its insertion into the abdomen.30 The laparoscopic access device consisted of a wound retractor, cap, and four 5- to 10-mm-diameter trocars. Insertion was performed by first creating a 5- to 7-cm ventral midline minilaparotomy incision centered at the level of the umbilicus. The wound retractor portion of the single port device was inserted by passing the inner flexible ring through the abdominal incision. The outer ring of the wound retractor was then rolled until it reached the body wall incision, resulting in taut circumferential retraction. The trocars were then inserted through the cap (prior to its attachment to the wound retractor), and the cap with preplaced trocars was then fitted to the outer ring of the wound retractor. Following insertion of the single-port platform, the peritoneal cavity was insufflated to a maximum pressure of 8 to 10 mm Hg with CO2 by means of a pressure-regulating mechanical insufflator,c and a 5-mm, 0°, 29-cm laparoscoped was inserted for abdominal exploration.
In patients that underwent multiport abdominal exploration and staging, abdominal access was obtained by means of a modified Hasson technique. An approximately 1-cm incision was made through the skin and subcutaneous tissues approximately 1 cm caudal to the umbilicus. The linea alba was identified, and 2 apposing stay sutures were placed in the rectus sheath. A stab incision was made into the linea alba, and a 6-mm, smooth trocar and cannula assemblye was introduced into the abdomen. The abdomen was then insufflated with CO2 to a maximum pressure of 8 to 10 mm Hg by means of a pressure-regulating mechanical insufflator.c An instrument portal was established either 5 cm cranial and 3 cm lateral to the camera portal or 5 cm cranial on the midline with direct observation by use of either a 6- or 10-mm-diameter smooth trocar and cannula assembly.e
Intracorporeal exploration was performed in a clockwise manner, commencing at the diaphragm and liver and continuing to the left abdominal gutter, caudal aspect of the abdomen, and right abdominal gutter.30 To facilitate maximal visualization of the abdominal gutters in some cases, the patient (positioned in dorsal recumbency) was rotated approximately 45° to each side by operating room personnel. The proximal portion of the gastrointestinal tract was evaluated intracorporeally by palpation of the stomach with a blunt probef and with the aid of laparoscopic Babcock forceps.30,g
Surgical technique: laparoscopic-assisted splenectomy
Following abdominal exploration and laparoscopic staging, the camera and instruments were removed, the abdomen was desufflated, and the single-port platform or subumbilical port was removed. The subumbilical incision was extended into a minilaparotomy depending on the estimated size of the spleen. A 5- to 9-cm wound retraction deviceh was inserted as previously described.31 In dogs in which the laparoscopic access device had been used, extension of the incision was not required because a 5- to 7-cm-long minilaparotomy incision had already been made and the wound retraction device was already in place. The tail of the spleen was grasped, and the spleen was partially exteriorized through the wound retractor or minilaparotomy incision. The splenic hilus and omental adhesions were progressively sealed and transected with a vessel-sealing devicei (Figure 1). The spleen was submitted for histologic evaluation.
Following LAS, extracorporeal exploration of the gastrointestinal tract was performed.30,31 A loop of jejunum was digitally grasped and exteriorized via the minilaparotomy. The exteriorized bowel was isolated with moistened laparotomy sponges and examined in the orad direction to the level of the caudal duodenal flexure and in the aborad direction to the ileocecocolic junction.
Intraoperative photographs of a representative dog during LAS illustrating initial partial exteriorization of the spleen via a wound retraction device to allow for sealing of hilar vessels (A) and eventual complete exteriorization of the spleen (B).
Citation: Journal of the American Veterinary Medical Association 248, 8; 10.2460/javma.248.8.916
Surgical technique: concurrent procedures
Adjunctive procedures were performed following intracorporeal abdominal exploration and laparoscopic staging or were performed extracorporeally after LAS as indicated.
Postoperative care
All patients were monitored postoperatively and received hydromorphone IV (0.05 mg/kg [0.023 mg/lb], q 4 to 6 h) or as a continuous rate infusion (0.05 to 0.1 mg/kg/h [0.023 to 0.045 mg/lb/h], IV) according to the judgment of the treating clinician. Patients were discharged at the discretion of the attending surgeon, with reevaluation recommended 14 days after surgery.
Results
Eighteen dogs met the study selection criteria. Median weight was 31.5 kg (69.3 lb; range, 4.8 to 54.6 kg [10.6 to 120.1 lb]), and median age was 111.1 months (range, 44.0 to 167.1 months). All patients underwent 3-view thoracic radiography and abdominal ultrasonography prior to LAS. A splenic mass lesion was the most common reason for splenectomy (n = 15). Splenectomy was also performed for suspected diffuse neoplasia (n = 2) and for immune-mediated disease nonresponsive to medical treatment (1). The median size (width × length) of the splenic masses was 5 × 5 cm (range, 1.6 to 11.0 cm × 1.5 to 14.5 cm).
For 17 of the 18 dogs, no abnormalities were seen on preoperative thoracic radiographs. In 1 dog, a diffuse nodular, interstitial pattern was detected. Abdominal ultrasonography revealed a splenic mass (n = 18); additional findings included a gastrointestinal mass (1), omental mass (1), fluid-filled uterus (1), liver mass (1), liver nodules (1), cystic calculi (1), and pancreatic mass (1).
Laparoscopic-assisted splenectomy technique and findings
A single-port platform (n = 16) or multiport (2) approach was used for initial abdominal exploration and staging. A multichannel single-port platform was used in 14 dogs, and a laparoscopic access device was used in 2 dogs. Minilaparotomy was performed via enlargement of the ventral midline portal incision for LAS in all cases, except the 2 patients in which the laparoscopic access device had been used. The median length of the minilaparotomy incision was 7.5 cm (range, 5 to 20 cm). A wound retractor device was placed in the minilaparotomy incision in 16 of 18 dogs. In the remaining 2 dogs, the spleen was removed via the minilaparotomy incision without use of any type of wound retractor.
Abdominal exploration and laparoscopic staging revealed omental adhesions (n = 6), a cecal mass (1), a fluid-filled uterus (1), a pancreatic nodule (1), a peritoneal mass (1), suspected hepatic lesions (1), liver nodules (2), a liver mass (1), and intestinal lacteal dilation (1). Results of preoperative abdominal ultrasonography were confirmed in all dogs during exploration and staging; however, in 2 patients, abdominal exploration identified hepatic lesions not detected during preoperative ultrasonography. Omental adhesions detected during abdominal exploration were not observed with preoperative ultrasonography in any patient. Median total surgical time for abdominal exploration and laparoscopic staging, LAS, and any concurrent procedures was 60 minutes (range, 45 to 130 minutes).
Concurrent procedures
Concurrent procedures were performed during LAS in 14 of 18 patients. These included liver biopsy (n = 11), esophagostomy tube placement (2), laparoscopic-assisted gastropexy (1), percutaneous cystolithotomy (1), ovariohysterectomy (1), pancreatic biopsy (1), gastrointestinal biopsies (1), typhlectomy (1), omental mass resection (1), right hemithyroidectomy (1), and bone marrow biopsy (1). The ovariohysterectomy was performed by means of a laparoscopic-assisted technique via the minilaparotomy incision. The percutaneous cystolithotomy was performed prior to LAS via cystoscopy through a separate abdominal incision. In 1 dog, 3 concurrent procedures (liver biopsy, laparoscopic-assisted gastropexy, and typhlectomy) were performed. Liver biopsy was performed during intracorporeal exploration and staging, followed by laparoscopic-assisted gastropexy. A minilaparotomy was performed for LAS. During the extracorporeal portion of abdominal exploration and staging, a cecal mass was identified and a typhlectomy was performed.
Perioperative complications
One of 18 dogs experienced mild hemorrhage during laparoscopic abdominal exploration and staging following inadvertent disruption of an omental adhesion. Hemorrhage was easily controlled with a vessel-sealing device.i No further treatment was required, and the patient recovered uneventfully. Additional perioperative complications were not encountered in any other patient.
Histopathologic findings
All spleens were submitted for histologic evaluation. Results of histopathologic examination included nodular hyperplasia (n = 7), hemangiosarcoma (4), soft tissue sarcoma (2), histiocytic sarcoma (1), metastatic mast cell tumor (1), hematoma (1), hemorrhagic infarct (1), and no abnormalities (1).
Perioperative outcome
All dogs survived to discharge. Median duration of postoperative hospitalization was 2 days (range, 2 to 4 days).
Discussion
Results of the present small multicenter retrospective case series conducted over a 2-year period (2012–2014) suggested that the technique for LAS described was a feasible, minimally invasive surgical option for total splenectomy in dogs with small- to medium-sized splenic masses or diffuse splenic disease. Previous studies23,27 in dogs and cats have suggested that LS is associated with decreased postoperative signs of pain, a more rapid return to usual activities, and a reduction in the incidence of surgical site infections. However, medium- to largesized splenic masses are considered contraindications for LS, which dramatically reduces candidates for LS because mass lesions are the most common indication for splenectomy in dogs.1,2 In the present study, selection of patients eligible for LAS was somewhat empirical, with massive splenic masses (10 cm × 10 cm as estimated on the basis of results of preoperative diagnostic imaging), primary splenic torsion, and hemoabdomen considered contraindications.
In the present study, abdominal exploration and laparoscopic staging were performed prior to splenectomy in all patients. In this series of cases, these steps were relatively easy and repeatable, and findings generally confirmed the results of preoperative abdominal ultrasonography. Because complete abdominal exploration cannot be performed during LAS, preoperative diagnostic imaging, specifically abdominal ultrasonography, is important. We suggest that laparoscopic abdominal exploration and staging, including both intra- and extracorporeal techniques, are key components of LAS, and note that we found additional hepatic lesions and omental adhesions not identified by means of ultrasonography in 2 of 18 patients in this case series. Further study comparing the results of laparoscopic abdominal exploration and staging with those of open surgical exploration in a larger number of cases is required to further evaluate the appropriate applications for LAS in dogs.
Laparoscopic splenectomy is a technically demanding procedure and may be associated with excessive hemorrhage, prolonged surgical times, and a high rate of conversion to open laparotomy in small animal patients.23,27 In addition, LS is not recommended for medium to large splenic masses (width × length, > 4 × 4 cm) because of concerns that excessive manipulation of the spleen will be required, which could potentially result in major hemorrhage, and this considerably reduces the number of dogs that may be candidates for this procedure. The technique for LAS described in the present report may provide many of the advantages of a minimally invasive approach with the relative technical ease of open splenectomy when performed by experienced laparoscopic surgeons. We further suggest that an additional advantage of LAS is the ability to perform intra- and extracorporeal exploration and staging. Extracorporeal exploration may not commonly be performed during LS.
In this study, the median minilaparotomy incision length was 7.5 cm (range, 5 to 20 cm) for dogs with a median body weight of 31.5 kg (range, 4.8 to 54.6 kg). This incision size is considerably shorter than that used for a standard open ventral midline laparotomy incision in a medium- to large-breed dog and comparable to minilaparotomy incisions performed for extraction of the spleen following 3-portal LS.24,25 Collard et al24 reported an LS technique for treatment of a 3-cm diameter midbody splenic mass and reported a minilaparotomy incision length of 7 cm to remove the affected spleen following intracorporeal sealing and transection of the splenic hilus. In a study25 of 10 clinically normal dogs, the minilaparotomy incision length was 7.2 ± 0.16 cm (mean ± SE) for 3-portal LS.25 As such, we believe that the LAS technique described in the present study results in minilaparotomy incisions for splenic extraction that are comparable to those reported for LS.
In human patients, morcellation of the spleen prior to extraction from the abdomen is commonly performed.33–35 This maintains smaller incision length without the need for extension into a minilaparotomy. Morcellation is currently not common in veterinary patients because of equipment cost and training requirements. However, if morcellation equipment increases in availability, LS in dogs might maintain an advantage over LAS because a minilaparotomy incision for splenic extraction would not be required. Currently, without the use of morcellation, we suggest that LS in dogs does not have a clear advantage when compared with LAS, is limited to dogs with relatively small splenic masses or diffuse disease, and may result in longer operative times.
Two dogs in this study required considerably longer minilaparotomy incisions, compared with the median incision length of 7.5 cm. Both dogs had large splenic masses (11 × 14.5 cm and 10 × 12 cm) as measured by means of preoperative ultrasonography, with associated minilaparotomy incisions of 16 cm and 20 cm, respectively. Many of the benefits of minimally invasive surgery may have been negated with the larger incisions. However, improved visualization and magnification during abdominal exploration and staging were still considered beneficial in the treatment of these 2 patients. In human patients, it has been reported that increasing splenic size directly correlated with the need for conversion to open splenectomy.11 Several studies have aimed to evaluate the impact of splenomegaly on the feasibility of LS. According to Filicori et al,36 splenic volume > 2,700 cm3 as determined by means of 3-D CT volumetry was an important predictor of the need for conversion from LS to open splenectomy.36 For spleens measuring < 2,700 cm3, the odds of conversion to an open procedure was considered low to moderate with experienced surgeons.36 On the basis of these results, the authors suggested that in patients with spleens with a 3-D reconstructed volume > 2,700 cm3 as measured with preoperative CT, an HALS may be more appropriate and associated with fewer complications.36 Similarly, Targarona et al11 reported that 77% of patients with spleens weighing ≤ 3,200 g underwent successful LS. Patients with spleens weighing > 3,200 g required conversion to open splenectomy in all cases.11 Studies involving use of CT for quantification of splenic size have not been performed in veterinary medicine. This would be a valuable area of future research to help best determine ideal candidates for LS or for LAS versus traditional open laparotomy.
A wound retraction deviceh was used in the 16 of 18 patients in this study and was found to be effective for circumferential atraumatic retraction of the body wall and splenic exteriorization. This inexpensive, self-expandable polyurethane device exerts a radial force to at the edges of the incision, providing optimal retraction and protecting the body wall from contact with exteriorized viscera.28,29,31 The laparoscopic access device may be an ideal single port platform for LAS because the wound retractor and incision for extraction of the spleen have already been created, which may reduce surgical time. Previous studies28,29,31 in veterinary patients have demonstrated the suggested benefits, including ease of exteriorization of viscera, smaller incisions, and decreased risk of contamination during laparoscopic-assisted procedures such as ovariohysterectomy and intestinal surgery. Studies37,38 in human patients have also demonstrated that placement of the wound retractor may reduce surgical site infection rates. In the present study, the device was found to be easy to place and facilitated abdominal access and atraumatic exteriorization of the spleen via relatively small minilaparotomy incisions. The device also functioned by protecting the body wall from potential contamination with neoplastic tissue at the time of removal from the peritoneal cavity. Care must be taken in cases of diffuse splenic disease where mast cell disease is a differential diagnosis because aggressive manipulation of the spleen through a minilaparotomy incision may increase the risk of degranulation.
A vessel-sealing devicei was used to seal and transect the splenic hilar vessels in all patients in this case series. The electrothermal bipolar sealing device causes hemostasis via compression and heat generation of the jaws and subsequent fusion of collagen and elastin in vessel walls.39–41 The device is advantageous for complete splenectomy in that it leaves no residual foreign material; reduces procedural time, compared with traditional methods of vessel ligation; has minimal risk of slippage; and is safe for sealing vessels up to 7 mm in diameter with < 2 mm of surrounding thermal damage.39–43 Furthermore, application of the vessel-sealing device does not require surgical dissection of the splenic hilus prior to sealing and transection of vessels, which facilitates progressive exteriorization of the spleen during LAS.39 The lack of need for surgical dissection of individual vessels in the splenic hilus allowed for reduced length of minilaparotomy incisions, less tension on the hilar vasculature, and increased ease of excision of affected spleens.
In this case series, median surgical time was 60 minutes (range, 45 to 130 minutes), including abdominal exploration and staging, LAS, and completion of any concurrent procedures, which is comparable to operative times for open splenectomy in dogs. Surgical time directly attributed to the LAS procedure was difficult to accurately assess because multiple dogs underwent concurrent procedures and, in many cases, the procedural time for LAS was not specified in the medical or anesthetic record. All 18 dogs in this case series survived to hospital discharge, with most dogs being discharged 24 hours after surgery. Possible disadvantages associated with LAS in dogs include the need for more advanced training and specialized equipment and the added expense of the procedure. We suggest that the increased expense associated with LAS may be offset by reduced hospitalization costs, compared with those of dogs undergoing splenectomy via a traditional open laparotomy; however, further studies are required to confirm this. As with any new procedure, operative times may initially be prolonged for patients undergoing LAS, compared with those undergoing traditional open laparotomy, because of the learning curve associated with procedure and inappropriate case selection. In our experience, abdominal exploration and staging was the most time-consuming portion of the procedure. Several studies have evaluated the learning curve for specific laparoscopic procedures in veterinary patients and may be illustrative.44,45
Limitations of this study include the small sample size and retrospective nature. Postoperative follow-up and outcome beyond the perioperative period was not included because the objective of the study was to describe a novel technique for performing minimally invasive LAS in dogs with small- to medium-sized splenic masses or diffuse disease. In the present small case series, we found LAS to be feasible and associated with few complications. This technique combines many of the benefits of a minimally invasive technique, including a small incision and improved illumination and magnification during exploration and staging. Nonetheless, careful case selection is imperative for procedural success. Further prospective studies are indicated comparing the results of LAS with the results of traditional open surgery in a larger number of cases to further evaluate the appropriate indications for LAS in dogs.
Acknowledgments
Presented in part at the 10th Annual Veterinary Endoscopy Society Meeting, Florence, Italy, April 2014.
ABBREVIATIONS
| HALS | Hand-assisted laparoscopic splenectomy |
| LAS | Laparoscopic-assisted splenectomy |
| LS | Laparoscopic splenectomy |
Footnotes
SILS port, Covidien Inc, Mansfield, Mass.
GelPort Laparoscopic System, Applied Medical Resources Corp, Rancho Santa Margarita, Calif.
Endoflator, Karl Storz Endoscopy, Goleta, Calif.
0° rigid telescope, Karl Storz Endoscopy, Goleta, Calif.
6 mm smooth trocar/cannula assembly, Karl Storz Endoscopy, Goleta, Calif.
Palpation probe, Karl Storz Endoscopy, Goleta, Calif.
Clickline, 5 mm, Straight Babcock Forceps, Karl Storz Endoscopy, Goleta, Calif.
Alexis Wound Retractor, Applied Medical Resources Corp, Rancho Santa Margarita, Calif.
Ligasure, Covidien Inc, Mansfield, Mass.
References
1. Richter MC. Spleen. In: Tobias KM, Johnston SA, eds. Veterinary surgery: small animal. St Louis: Elsevier Saunders, 2012;1341–1352.
2. Spangler WL, Culbertson MR. Prevalence, type, and importance of splenic diseases in dogs: 1,480 cases (1985–1989). J Am Vet Med Assoc 1992; 200: 829–834.
3. Delaitre B, Maignien B. Splenectomy by the laparoscopic approach. Report of a case [in French]. Presse Med 1991; 20: 2263.
4. Gamme G, Birch DW, Karmali S. Minimally invasive splenectomy: an update and review. Can J Surg 2013; 56: 280–285.
5. Winslow ER, Brunt LM. Perioperative outcomes of laparoscopic versus open splenectomy: a meta-analysis with an emphasis on complications. Surgery 2003; 134: 647–653.
6. Brunt LM, Langer JC, Quasebarth MA, et al. Comparative analysis of laparoscopic versus open splenectomy. Am J Surg 1996; 172: 596–601.
7. Park A, Maracaccio M, Sternbach M, et al. Laparoscopic vs open splenectomy. Arch Surg 1999; 134: 1263–1269.
8. Feng S, Qiu Y, Li X, et al. Laparoscopic versus open splenectomy in children: a systematic review and meta-analysis [Published online ahead of print Dec 11, 2015]. Pediatr Surg Int doi:10.1007/s00383-015-3845-2.
9. Patel AG, Parker JE, Wallwork B, et al. Massive splenomegaly is associated with significant morbidity after laparoscopic splenectomy. Ann Surg 2003; 238: 235–240.
10. Kercher KW, Matthews BD, Walsh RM, et al. Laparoscopic splenectomy for massive splenomegaly. Am J Surg 2002; 183: 192–196.
11. Targarona EM, Espert JJ, Cerdan G, et al. Effect of spleen size on splenectomy outcome. A comparison of open and laparoscopic surgery. Surg Endosc 1999; 13: 559–562.
12. Swanson TW, Meneghetti A, Sampath S, et al. Hand-assisted laparoscopic splenectomy versus open splenectomy for massive splenomegaly: 20-year experience at a Canadian centre. Can J Surg 2011; 54: 189–193.
13. Kuminsky RE, Boland JP, Tiley EH, et al. Hand-assisted laparoscopic splenectomy. Surg Laparosc Endosc Percutan Tech 1995; 5: 436–467.
14. Kaban GK, Czerniach DR, Cohen R, et al. Hand-assisted laparoscopic splenectomy in the setting of splenomegaly. Surg Endosc 2004; 18: 1340–1343.
15. Rosen M, Brody F, Walsh RM, et al. Hand-assisted laparoscopic splenectomy vs conventional laparoscopic splenectomy in cases of splenomegaly. Arch Surg 2002; 137: 1348–1352.
16. Habermalz B, Sauerland S, Decker G, et al. Laparoscopic splenectomy: the clinical practice guidelines of the European Association for Endoscopic Surgery (EAES). Surg Endosc 2008; 22: 821–848.
17. Qian D, He Z, Hua J, et al. Hand-assisted versus conventional laparoscopic splenectomy: a systematic review and meta-analysis. ANZ J Surg 2014; 84: 915–920.
18. Targarona EM, Balague C, Cerdan G, et al. Hand-assisted laparoscopic splenectomy (HALS) in cases of splenomegaly. Surg Endosc 2002; 16: 426–430.
19. Bleedorn JA, Dykema JL, Hardie RJ. Minimally invasive surgery in veterinary practice: a 2010 survey of diplomates and residents of the American College of Veterinary Surgeons. Vet Surg 2013; 42: 635–642.
20. Culp WT, Mayhew PD, Brown DC. The effect of laparoscopic versus open ovariectomy on postsurgical activity in small dogs. Vet Surg 2009; 38: 811–817.
21. Devitt CM, Cox RE, Hailey JJ. Duration, complications, stress, and pain of open ovariohysterectomy versus a simple method of laparoscopic-assisted ovariohysterectomy in dogs. J Am Vet Med Assoc 2005; 227: 921–927.
22. Mayhew PD, Freeman L, Kwan T, et al. Comparison of surgical site infection rates in clean and clean-contaminated wounds in dogs and cats after minimally invasive versus open surgery: 179 cases (2007–2008). J Am Vet Med Assoc 2012; 240: 193–198.
23. Stedile R, Beck CA, Schiochet F, et al. Laparoscopic versus open splenectomy in dogs. Pesq Vet Bras 2009; 29: 653–660.
24. Collard F, Nadeau ME, Carmel EN. Laparoscopic splenectomy for treatment of splenic hemangiosarcoma in a dog. Vet Surg 2010; 39: 870–872.
25. Khalaj A, Bakhtiari J, Niasari-Naslaji A. Comparison between single and three portal laparoscopic splenectomy in dogs. BMC Vet Res 2012; 8: 161.
26. Shaver SL, Mayhew PD, Steffey MA, et al. Short-term outcome of multiple port laparoscopic splenectomy in 10 dogs. Vet Surg 2015; 44 (suppl 1):71–75.
27. O'Donnell E, Mayhew P, Culp W, et al. Laparoscopic splenectomy: operative technique and outcome in three cats. J Feline Med Surg 2013; 15: 48–52.
28. Adamovich-Rippe KN, Mayhew PD, Runge JJ, et al. Evaluation of laparoscopic-assisted ovariohysterectomy for treatment of canine pyometra. Vet Surg 2013; 42: 572–578.
29. Baron JK, Giuffrida M, Runge JJ. Evaluation of minimally invasive abdominal exploration and intestinal biopsies (MIAEB) using a novel wound retraction device in cats: 31 cases (2005–2013), in Proceedings. Am Coll Vet Surg Annu Meet 2014.
30. Case JB, Ellison G. Single incision laparoscopic-assisted intestinal surgery (SILAIS) in 7 dogs and 1 cat. Vet Surg 2013; 42: 629–634.
31. Gower SB, Mayhew PD. A wound retraction device for laparoscopic-assisted intestinal surgery in dogs and cats. Vet Surg 2011; 40: 485–488.
32. Rawlings CA. Laparoscopic-assisted gastropexy. J Am Anim Hosp Assoc 2002; 38: 15–19.
33. Greene AK, Hodin RA. Laparoscopic splenectomy for massive splenomegaly using a Lahey bag. Am J Surg 2001; 181: 543–546.
34. Targarona EM, Balague C, Trias M. Is the laparoscopic approach reasonable in cases of splenomegaly? Semin Laparosc Surg 2004; 11: 185–190.
35. Ozemir IA, Bayraktar B, Bayraktar O, et al. Single-site multiport combined splenectomy and cholecystectomy with conventional laparoscopic instruments: case series and review of literature. Int J Surg Case Rep 2015; 19: 41–46.
36. Filicori F, Stock C, Schweitzer AD, et al. Three-dimensional CT volumetry predicts outcome of laparoscopic splenectomy for splenomegaly: a retrospective clinical study. World J Surg 2013; 37: 52–58.
37. Horiuchi T, Tanishima H, Tamagawa K, et al. Randomized, controlled investigation of the anti-infective properties of the Alexis retractor/protector of incision sites. J Trauma 2007; 62: 212–215.
38. Cheng KP, Roslani AC, Sehha N, et al. ALEXIS O-ring wound retractor vs conventional wound protection for the prevention of surgical site infections in colorectal resections. Colorectal Dis 2012; 14:e346–e351.
39. Rivier P, Monnet E. Use of a vessel sealant device for splenectomy in dogs. Vet Surg 2011; 40: 102–105.
40. Kennedy JS, Stranahan PL, Taylor KD, et al. High-burst strength, feedback controlled bipolar vessel sealing. Surg Endosc 1998; 12:876–878.
41. Heniford BT, Matthews BD, Sing RF, et al. Initial results with an electrothermal bipolar vessel sealer. Surg Endosc 2001; 15: 799–801.
42. Monarski CJ, Jaffe MH, Kass PH. Decreased surgical time with a vessel sealing device versus a surgical stapler in performance of canine splenectomy. J Am Anim Hosp Assoc 2014; 50: 42–45.
43. Gelmini R, Romano F, Quaranta N, et al. Sutureless and stapleless laparoscopic splenectomy using radiofrequency: LigaSure device. Surg Endosc 2006; 20: 991–994.
44. Arulpragasam SP, Case JB, Ellison GW. Evaluation of costs and time required for laparoscopic-assisted versus open cystotomy for urinary cystolith removal in dogs: 43 cases (2009–2012). J Am Vet Med Assoc 2013; 243: 703–708.
45. Runge JJ, Boston RC, Ross SB, et al. Evaluation of the learning curve for a board-certified veterinary surgeon performing laparoendoscopic single-site ovariectomy in dogs. J Am Vet Med Assoc 2014; 245: 828–835.
