Completion pancreatectomy during pancreatoduodenectomy: A lifesaving solution in high-risk patients.

BACKGROUND: Postoperative pancreatic fistula (POPF) is responsible of most major complications and fatalities after PD. By avoiding POPF, TP may improve operative outcomes in high-risk patients. The aim was to compare total pancreatectomy (TP) and pancreatoduodenectomy (PD) in high-risk patients and evaluate results of implementing a risk-tailored strategy in clinical practice. METHODS: Between 2014 and 2023, 139 patients (76 men, median age 67 years) underwent resection of disease located in the head of the pancreas. Starting January 1, 2022, we offered TP to patients at high POPF risks (fistula risk score (FRS) ≥7) and to patients with intermediate POPF risks (FRS: 3-6) and high risks of failure to rescue (age> 75 years, ASA score ≥3). We compared outcomes of TP and PD and evaluated the results of the new strategy implementation on operative outcomes. Propensity score-based analysis was performed to limit bias of between-group comparison. RESULTS: Eventually, 26 (19%) patients underwent TP and 113 (81%) patients underwent PD. Severe complications occurred in 42 (30%) patients and 13 (9%) patients died. TP resulted in shorter lengths of hospital stay (median: 14 days [11; 18] vs. 17 days [13; 24], p = 0.016) and less risks of post-pancreatectomy hemorrhage (PPH) (0% vs. 20%, p < 0.001) compared to PD. Crude and propensity match analysis showed that the implementation of a risk-tailored strategy led to significant reduction of reoperation, POPF, PPH and mortality rates. CONCLUSION: The use of TP as part of a risk-tailored strategy in high-risk patients can be lifesaving.

Alternative forms of portal vein revascularization in liver transplant recipients with complex portal vein thrombosis.

BACKGROUND & AIMS: Complex portal vein thrombosis (PVT) is a challenge in liver transplantation (LT). Extra-anatomical approaches to portal revascularization, including renoportal (RPA), left gastric vein (LGA), pericholedochal vein (PCA), and cavoportal (CPA) anastomoses, have been described in case reports and series. The RP4LT Collaborative was created to record cases of alternative portal revascularization performed for complex PVT. METHODS: An international, observational web registry was launched in 2020. Cases of complex PVT undergoing first LT performed with RPA, LGA, PCA, or CPA were recorded and updated through 12/2021. RESULTS: A total of 140 cases were available for analysis: 74 RPA, 18 LGA, 20 PCA, and 28 CPA. Transplants were primarily performed with whole livers (98%) in recipients with median (IQR) age 58 (49-63) years, model for end-stage liver disease score 17 (14-24), and cold ischemia 431 (360-505) minutes. Post-operatively, 49% of recipients developed acute kidney injury, 16% diuretic-responsive ascites, 9% refractory ascites (29% with CPA, p <0.001), and 10% variceal hemorrhage (25% with CPA, p = 0.002). After a median follow-up of 22 (4-67) months, patient and graft 1-/3-/5-year survival rates were 71/67/61% and 69/63/57%, respectively. On multivariate Cox proportional hazards analysis, the only factor significantly and independently associated with all-cause graft loss was non-physiological portal vein reconstruction in which all graft portal inflow arose from recipient systemic circulation (hazard ratio 6.639, 95% CI 2.159-20.422, p = 0.001). CONCLUSIONS: Alternative forms of portal vein anastomosis achieving physiological portal inflow (i.e., at least some recipient splanchnic blood flow reaching transplant graft) offer acceptable post-transplant results in LT candidates with complex PVT. On the contrary, non-physiological portal vein anastomoses fail to resolve portal hypertension and should not be performed. IMPACT AND IMPLICATIONS: Complex portal vein thrombosis (PVT) is a challenge in liver transplantation. Results of this international, multicenter analysis may be used to guide clinical decisions in transplant candidates with complex PVT. Extra-anatomical portal vein anastomoses that allow for at least some recipient splanchnic blood flow to the transplant allograft offer acceptable results. On the other hand, anastomoses that deliver only systemic blood flow to the allograft fail to resolve portal hypertension and should not be performed.

Degradable Bioadhesives Based on Star PEG-PLA Hydrogels for Soft Tissue Applications.

Tissue adhesives are interesting materials for wound treatment as they present numerous advantages compared to traditional methods of wound closure such as suturing and stapling. Nowadays, fibrin and cyanoacrylate glues are the most widespread commercial biomedical adhesives, but these systems display some drawbacks. In this study, degradable bioadhesives based on PEG-PLA star-shaped hydrogels are designed. Acrylate, methacrylate, and catechol functional copolymers are synthesized and used to design various bioadhesive hydrogels. Various types of mechanisms responsible for adhesion are investigated (physical entanglement and interlocking, physical interactions, chemical bonds), and the adhesive properties of the different systems are first studied on a gelatin model and compared to fibrin and cyanoacrylate references. Hydrogels based on acrylate and methacrylate reached adhesion strength close to cyanoacrylate (332 kPa) with values of 343 and 293 kPa, respectively, whereas catechol systems displayed higher values (11 and 19 kPa) compared to fibrin glue (7 kPa). Bioadhesives were then tested on mouse skin and human cadaveric colonic tissue. The results on mouse skin confirmed the potential of acrylate and methacrylate gels with adhesion strength close to commercial glues (15-30 kPa), whereas none of the systems led to high levels of adhesion on the colon. These data confirm that we designed a family of degradable bioadhesives with adhesion strength in the range of commercial glues. The low level of cytotoxicity of these materials is also demonstrated and confirm the potential of these hydrogels to be used as surgical adhesives.

Endovascular Lymphatic Decompression via Thoracic Duct Stent Placement for Refractory Ascites in Patients with Cirrhosis: A Pilot Study.

PURPOSE: To evaluate the technical and clinical success of endovascular lymphatic decompression via thoracic duct (TD) stent placement in patients with cirrhosis with refractory ascites. MATERIALS AND METHODS: Nine patients (6 men and 3 women; median age, 66 [interquartile range {IQR}, 65-68] years; range, 62-78 years) who underwent TD stent placement for refractory ascites with contraindications for liver transplantation and transjugular intrahepatic portosystemic shunt creation were included in this retrospective study. TD stent placement was performed under local anesthesia using retrograde access from the venous system. Self-expanding stents from 5 to 8 mm in diameter were used and extended into the subclavian vein by approximately 1 cm. Technical (correct positioning of the stent) and clinical success (no more requirement of paracentesis) were evaluated. In addition, the safety of the procedure and TD pressure evolution were evaluated. RESULTS: The technical success rate was 100%, and 3 (33%) patients reported clinical success. Five (56%) patients reported 7 minor adverse events (Grade I), among which 2 TD perforations were induced by stent angioplasty, with no clinical manifestation or treatment required. The median TD pressure decreased from 19 mm Hg (IQR, 11-24 mm Hg) at the beginning of the procedure to 6 mm Hg (IQR, 5-11 mm Hg) after TD stent placement. The median survival time after the procedure was 7.1 months. CONCLUSIONS: Endovascular lymphatic decompression via TD stent placement is feasible and safe and was effective on ascites in some patients with cirrhosis with refractory ascites.

The Angers CT Score is a Risk Factor for the Failure of the Conservative Management of Adhesive Small Bowel Obstruction: A Prospective Observational Multicentric Study.

BACKGROUND: Identifying the 30% of adhesive small bowel obstructions (aSBO) for which conservative management will require surgery is essential. The association between the previously described radiological score and failure of the conservative management of aSBO remains to be confirmed in a large prospective multicentric cohort. Our aim was to assess the risk factors of failure of the conservative management of aSBO considering the radiological score. MATERIAL AND METHODS: This prospective observational study took place in 15 French centers over 3 months. Consecutive patients experiencing aSBO with no early surgery were included. The six radiological features from the Angers radiological computed tomography (CT) score were noted (beak sign, closed loop, focal or diffuse intraperitoneal liquid, focal or diffuse mesenteric haziness, focal or diffuse mesenteric liquid, and diameter of the most dilated small bowel loop > 40 mm). RESULTS: Two hundred and seventy nine patients with aSBO were screened. Sixty patients (21.5%) underwent early surgery, and 219 (78.5%) had primary conservative management. In the end, 218 patients were included in the analysis of the risk factors for conservative treatment failure. Among them, 162 (74.3%) had had successful management while for 56 (25.7%) management had failed. In multivariate analysis, a history of surgery was not a significant risk factor for the failure of conservative treatment (OR = 0.11; 95%CI = 0-1.23). A previous episode of aSBO was protective against the failure of conservative treatment (OR = 0.36; 95%CI = 0.15-0.85) and an Angers CT score ≥ 5 as the only individual risk factor (OR = 2.39; 95%CI = 1.01-5.69). CONCLUSION: The radiological score of aSBO is a promising tool in improving the management of aSBO patients. A first episode of aSBO and/or a radiological score ≥5 should lead physicians to consider early surgical management.

Prognostic impact of splenic vessel involvement and tumor size in distal pancreatectomy for adenocarcinoma: a retrospective multicentric cohort study.

PURPOSE: Splenic vessel involvement occurs frequently in pancreatic ductal adenocarcinoma (PDAC) of the body and the tail (B/T) but the impact on survival is unknown. We assessed the influence of radiological and pathologic involvement of splenic artery (p-SA +) and vein (p-SV +) on patient outcomes after distal pancreatectomy (DP) for PDAC. METHODS: From 2013 to 2019, all DP for PDAC in five centers were included. Factors associated with overall (OS) and disease-free (DFS) survival were identified. RESULTS: Among the 76 patients included, 5 (6.6%) had p-SA + only, 11 (14.5%) had p-SV + only, and 24 (31.6%) had both p-SA + and p-SV + . The preoperative CT-scan accuracy to predict p-SV + and p-SA + was high (sensitivity: 91.4% and 82.8%, respectively; negative predictive value: 89.7% and 88.3%, respectively). The 5-year OS and DFS rates were 3.9% and 8.3%, respectively. Multivariate analysis identified splenic vessel involvement (i.e., p-SA + or p-SV + , or both p-SA + and p-SV +) as the only independent factor influencing DFS (HR 4.04; 95% CI [1.22-13.44], p = 0.023). Tumor size ≥ 30 mm was the only independent factor influencing OS (HR 4.04; 95% CI [1.26-12.95], p = 0.019) and was associated with a high risk of p-SA + (p = 0.001) and p-SV + (p < 0.001). CONCLUSION: Tumor size ≥ 30 mm and splenic vessel involvement occurred in more than half of the patients who underwent DP for PDAC and had negative impact on long-term survival. Preoperative CT-scan was reliable to identify splenic vessel involvement in B/T PDAC. Large tumor size and radiological splenic vessel involvement could be taken into account to propose a neoadjuvant treatment.

Delayed Postoperative Hemorrhage Complicating Major Supramesocolic Surgery Management and Outcomes.

BACKGROUND: The place of surgery and interventional radiology in the management of delayed (> 24 h) hemorrhage (DHR) complicating supramesocolic surgery is still to define. The aim of the study was to evaluate outcomes of DHR using a combined multimodal strategy. METHODS: Between 2005 and 2019, 57 patients (median age 64 years) experienced 86 DHR episodes after pancreatic resection (n = 26), liver transplantation (n = 24) and other (n = 7). Hemodynamically stable patients underwent computed tomography evaluation followed by interventional radiology (IR) treatment (stenting and/or embolization) or surveillance. Hemodynamically unstable patients were offered upfront surgery. Failure to identify the leak was managed by either prophylactic stenting/embolization of the most likely bleeding source or surveillance. RESULTS: Mortality was 32% (n = 18). Bleeding recurrence occurred in 22 patients (39%) and was multiple in 7 (12%). Sentinel bleeding was recorded in 77 (81%) of episodes, and the bleeding source could not be identified in 26 (30%). Failure to control bleeding was recorded in 9 (28%) of 32 episodes managed by surgery and 4 (11%) of 41 episodes managed by IR (p = 0.14). Recurrence was similar after stenting and embolization (n = 4/18, 22% vs n = 8/26, 31%, p = 0.75) of the bleeding source. Recurrence was significantly lower after prophylactic IR management than surveillance of an unidentified bleeding source (n = 2/10, 20% vs. n = 11/16, 69%, p = 0.042). CONCLUSION: IR management should be favored for the treatment of DHR in hemodynamically stable patients. Prophylactic IR management of an unidentified leak decreases recurrence risks.

Delayed post-pancreatectomy hemorrhage and bleeding recurrence after percutaneous endovascular treatment: risk factors from a bi-centric study of 307 consecutive patients.

PURPOSE: Delayed post-pancreatectomy hemorrhage (PPH) is still one of the most dreaded complications after pancreatic surgery. Its management is now focused on percutaneous endovascular treatments (PETs). METHODS: Between 2013 and 2019, 307 patients underwent pancreatic resection. The first endpoint of this study was to determine predictive factors of delayed PPH. The second endpoint was to describe the management of intra-abdominal abscesses (IAA). The third endpoint was to identify risk factors of bleeding recurrence after PET. Patients were divided into two cohorts: A retrospective analysis was performed ("cohort 1," "learning set") to highlight predictive factors of delayed PPH. Then, we validated it on a prospective maintained cohort, analyzed retrospectively ("cohort 2," "validation set"). Second and third endpoints studies were made on the entire cohort. RESULTS: In cohort 1, including 180 patients, 24 experienced delayed PPH. Multivariate analysis revealed that POPF diagnosis on postoperative day (POD) 3 (p=0.004) and IAA (p=0.001) were independent predictive factors of delayed PPH. In cohort 2, association of POPF diagnosis on POD 3 and IAA was strongly associated with delayed PPH (area under the curve [AUC] 0.80; 95% confidence interval [CI] [0.59-0.94]; p=0.003). Concerning our second endpoint, delayed PPH occurred less frequently in patients who underwent postoperative drainage procedure than in patients without IAA drainage (p=0.002). Concerning our third endpoint, a higher body mass index (BMI) (p=0.027), occurrence of postoperative IAA (p=0.030), and undrained IAA (p=0.011) were associated with bleeding recurrence after the first PET procedure. CONCLUSION: POPF diagnosis on POD 3 and intra-abdominal abscesses are independent predictive factors of delayed PPH. Therefore, patients presenting an insufficiently drained POPF leading to intra-abdominal abscess after pancreatic surgery should be considered as a high-risk situation of delayed PPH. High BMI, occurrence of postoperative IAA, and undrained IAA were associated with recurrence of bleeding after PET.

Feasibility and safety of laparoscopic colorectal surgeries for patients with left ventricular assist device.

PURPOSE: There is limited literature regarding the feasibility and safety of laparoscopic procedures in patients having mechanical circulatory support, especially colonic resections. METHODS: The aim of this study is to present the case of a laparoscopic colectomy for cancer undergone in a 69-year-old patient having a HeartWare II at our institution without any postoperative major complications and to describe the perioperative management and outcome of these patients according to the literature, regarding the hemodynamic, hemorrhagic, and infectious risks and the safety of this procedure. RESULTS: There was no 90-day postoperative morbidity or death. A total of six patients including ours were identified in the study. This study has a limited number of patients and relatively short follow-up time. CONCLUSION: Even though the management of patients having a LVAD is challenging and needs a multidisciplinary approach, reported literatures have shown the safety and feasibility of laparoscopic interventions for colorectal surgeries.

Short-term outcomes of the over-the-scope clip proctology system for rectovaginal fistula repair: a prospective study.

BACKGROUND: The over-the-scope clip proctology system is rather new and information regarding its use for the closure of anorectal fistulas is scarce. No study has been designed to focus exclusively on its application in the treatment of rectovaginal fistulas. The aim of the study was to evaluate the feasibility, safety, and effectiveness of the clip for rectovaginal fistula repair. METHODS: From September 2014 to November 2017, consecutive patients underwent a rectovaginal fistula repair using the over-the-scope clip proctology system and were enrolled in a non-randomized prospective monocentric study. The primary outcome was fistula healing at 8 months. Secondary outcomes included assessment of morbidity and timing of rectovaginal fistula recurrence. RESULTS: There were 16 patients with a median age of 40.1 years. The most common causes of rectovaginal fistula were adverse events following proctectomy or pelvic radiotherapy (6 patients), obstetric trauma (5 patients) and inflammatory bowel disease (3 patients). Most participants had undergone at least two previous surgical interventions before the clipping procedure. 11 patients had a temporary diverting stoma at time of the clipping procedure. Successful primary healing of the fistula was observed in 7 (43.7%) patients. Short-term complications were rare and included pain, which occurred in 4 patients, and spontaneous clip detachment, which occurred in 2 patients. Most recurrences appeared shortly after the procedure, with a median delay of 45 days (range 16-217). CONCLUSIONS: We demonstrated the feasibility, safety, and reproducibility of the Over-The-Scope Clip Proctology system in rectovaginal fistula repair for the patients selected. Further trials should be designed, incorporating comparisons to well-established techniques, a longer follow-up period, and a larger cohort.

Preoperative Biliary Stenting and Major Morbidity After Pancreatoduodenectomy: Does Elapsed Time Matter?: The FRAGERITA Study Group.

OBJECTIVE: To analyze possible associations between the duration of stent placement before surgery and the occurrence and severity of postoperative complications after pancreatoduodenectomy (PD). BACKGROUND: The effect of preoperative stent duration on postoperative outcomes after PD has not been investigated. METHODS: From 2013 to 2016, patients who underwent PD for any reasons after biliary stent placement at 5 European academic centers were analyzed from prospectively maintained databases. The primary aim was to investigate the association between the duration of preoperative biliary stenting and postoperative morbidity. Patients were stratified by stent duration into 3 groups: short (<4 weeks), intermediate (4-8 weeks), and long (≥8 weeks). RESULTS: In all, 312 patients were analyzed. The median time from stent placement to surgery was 37 days (2-559 days), and most operations were performed for pancreatic cancer (67.6%). Morbidity and mortality rates were 56.0% and 2.6%, respectively. Patients in the short group (n = 106) experienced a higher rate of major morbidity (43.4% vs 20.0% vs 24.2%; P < 0.001), biliary fistulae (13.2% vs 4.3% vs 5.5%; P = 0.031), and length of hospital stay [16 (10-52) days vs 12 (8-35) days vs 12 (8-43) days; P = 0.025]. A multivariate adjusted model identified the short stent duration as an independent risk factor for major complications (odds ratio 2.64, 95% confidence interval 1.23-5.67, P = 0.013). CONCLUSIONS: When jaundice treatment cannot be avoided, delaying surgery up to 1 month after biliary stenting may reduce major morbidity, procedure-related complications, and length of hospital stay.

Damage Control Surgery for Non-traumatic Abdominal Emergencies.

BACKGROUND: Damage control surgery (DCS) was a major paradigm change in the management of critically ill trauma patients and has gradually expanded in the general surgery arena, but data in this setting are still scarce. The study aim was to evaluate outcomes of DCS in patients with general surgery emergencies. METHODS: Between 2005 and 2015, 164 patients (104 men, age 66) underwent DCS for non-traumatic abdominal emergencies. The decision to perform DCS was triggered by the presence of at least one trauma DCS criterion: hypotension (<70 mmHg), hypothermia (<35 °C), acidosis (pH < 7.25), coagulopathy (INR ≥ 1.7) and massive (>5 RBC) transfusion. Statistical tests were performed to identify risk factors for operative mortality. Observed outcomes were compared to those predicted by commonly employed scores (APACHE II, POSSUM, P-POSSUM, SAPS II). RESULTS: DCS was performed for acute mesenteric ischemia (n = 68), peritonitis (n = 44), pancreatitis (n = 28), bleeding (n = 14) and other (n = 10). Abdominal compartment syndrome was associated in 52 patients (32%). Seventy-four (45%) patients died and 150 patients (91%) experienced complications. On multivariate analysis, age (p = 0.018) and INR ≥ 1.7 (p = 0.001) were independent predictors of mortality. Mortality was 24% (13/55), 48% (22/46) and 62% (39/63) in patients with one, two and ≥3 DCS criteria, respectively. Comparison of observed and score-predicted mortality suggested DCS use resulted in significant survival benefit of the whole cohort and of patients with pancreatitis and postoperative peritonitis. CONCLUSIONS: DCS can be lifesaving in critically ill patients with general surgery emergencies. Patients with peritonitis and acute pancreatitis are those who benefit most of the DCS approach.

Internal biliary stenting in liver transplantation.

PURPOSE: Internal biliary stenting (IBS) was reported to decrease biliary complications after liver transplantation (LT) but data in literature is scarce. The aim of the present study was to evaluate our experience with end-to-end choledoco-choledocostomy during liver transplantation with special focus on the influence of IBS on patient and biliary outcomes. METHODS: Between 2009 and 2013, 175 patients underwent deceased donor LT with end-to-end choledoco-choledocostomy and were included in the study. Supra-papillary silastic stent was inserted in 67 patients (38%) with small-size (< 5 mm) bile ducts (recipient or donor). Endoscopic retrograde cholangiopancreatography (ERCP) was scheduled for IBS removal, 6 months after LT. Operative outcomes and survival of patients who received internal stenting (IBS group) were compared with those of patients who did not (no-IBS group). Risk factors for biliary anastomotic complications were identified. RESULTS: Ten patients died (6%) and 104 (59%) experienced postoperative complications. Five-year patient and graft survival rates were 77 and 74%, respectively. Biliary complications were recorded in 61 patients (35%) and were significantly decreased by IBS insertion (p = 0.0003). Anastomotic fistulas occurred in 23 patients (13%) and stenoses in 44 patients (25%). On multivariate analysis, high preoperative MELD scores (p = 0.02) and hepatic artery thrombosis (p < 0.0001) were predictors of fistula; absence of IBS was associated with both fistula (p = 0.014) and stricture (p = 0.003) formation. CONCLUSIONS: IBS insertion during LT decreases anastomotic complication.

Energy vessel sealing systems versus mechanical ligature of the inferior mesenteric artery in laparoscopic sigmoidectomy.

PURPOSE: With the development of new devices, our ligation technique of the inferior mesenteric artery changed from mechanical ligature (ML) to energized vessel sealing systems (EVSS) ligature. The aim of this study was to determine if EVSS could be considered as safe and effective as the more convention ML of the inferior mesenteric vessels division during elective laparoscopic left colectomy. METHODS: Between 2001 and 2014, 200 consecutive patients (111 males) of mean age 54.1 years were operated laparoscopically for a symptomatic sigmoid diverticulitis. Vascular interruptions were performed using mechanical ligatures including double clipping, staples or surgical thread (100 patients) or, starting from 2006, with EVSS thereafter (100 patients). Section of the inferior mesenteric artery is performed systematically at its origin in our institution for teaching purposes. Technical results were prospectively collected perioperatively and postoperatively. RESULTS: There was no mortality. Mean operating time was 253.7 and 200.7 min in the ML and EVSS groups, respectively (p < 0.001). Mean hospital stay was 10.4 and 8.1 days (p < 0.001). Thirty-day complications occurred in 31 versus 25 % of patients (p = 0.26). Leakage with peritonitis occurred in 3 patients in the ML group. Hemorrhagic events occurred in both groups (2 in ML group versus 1 in EVSS group). Limitations of the study are its retrospective design and the bias due to the comparison of two historical cohorts. CONCLUSIONS: EVSS for the inferior mesenteric artery are as safe and effective as ML in elective sigmoidectomy for diverticular disease with lower operative time and hospital stay.

[Intestinal obstruction, an overview]. / L'occlusion intestinale, état des lieux.

Intestinal obstruction is a pathology commonly encountered in emergency and surgical departments. Its origin is usually mechanical, caused by obstruction of the digestive tract. It is a therapeutic emergency. Surgical treatment is required for the most severe cases.

Mechanical experimentation of the gastrointestinal tract: a systematic review.

The gastrointestinal (GI) organs of the human body are responsible for transporting and extracting nutrients from food and drink, as well as excreting solid waste. Biomechanical experimentation of the GI organs provides insight into the mechanisms involved in their normal physiological functions, as well as understanding of how diseases can cause disruption to these. Additionally, experimental findings form the basis of all finite element (FE) modelling of these organs, which have a wide array of applications within medicine and engineering. This systematic review summarises the experimental studies that are currently in the literature (n = 247) and outlines the areas in which experimentation is lacking, highlighting what is still required in order to more fully understand the mechanical behaviour of the GI organs. These include (i) more human data, allowing for more accurate modelling for applications within medicine, (ii) an increase in time-dependent studies, and (iii) more sophisticated in vivo testing methods which allow for both the layer- and direction-dependent characterisation of the GI organs. The findings of this review can also be used to identify experimental data for the readers' own constitutive or FE modelling as the experimental studies have been grouped in terms of organ (oesophagus, stomach, small intestine, large intestine or rectum), test condition (ex vivo or in vivo), number of directions studied (isotropic or anisotropic), species family (human, porcine, feline etc.), tissue condition (intact wall or layer-dependent) and the type of test performed (biaxial tension, inflation-extension, distension (pressure-diameter), etc.). Furthermore, the studies that investigated the time-dependent (viscoelastic) behaviour of the tissues have been presented.