Evaluation of Rex Shunt on Cavernous Transformation of the Portal Vein in Children

Location and extent of cavernous transformation of the portal vein dictates different visceral side revascularization in Meso-Rex bypass

BACKGROUND

As an emerging standard of care for portal vein cavernous transformation (PVCT), Meso-Rex bypass (MRB) has been complicated and variated. The study aim was to propose a new classification of PVCT to guide MRB operations.

METHODS

Demographic data, the extent of extrahepatic PVCT, surgical methods for visceral side revascularization, intraoperative blood loss, operating time, changes in visceral venous pressure before and after MRB, postoperative complications and the condition of bypass vessels after MRB were extracted retrospectively from the medical records of 19 patients.

RESULTS

The median age of the patients (13 males and 6 females) was 32.5 years, while two patients were underage. Causes of PVCT can be summarized as follows: thrombophilia such as dysfunction of antithrombin III or proteins C; secondary to abdominal surgeries; secondary to abdominal infection or traumatic intestinal obstruction, and unknown causes. Intraoperatively, the median operation time was 9.5 h (7-13 h), and the intraoperative blood loss was 300 mL (100-1,600 mL). Ten cases used autologous blood vessels while 10 used allogeneic blood vessels. The vascular anastomosis was divided into the following types according to the site and approach: Type (T) 1-PV pedicel type, T2-confluence type, T3-major visceral vascular type; and T4-collateral visceral vascular type. Furthermore, the visceral venous pressure before and after MRB dropped significantly from 36 cmH2O (28-44) to 24.5 cmH2O (15-31) (P < 0.01). Postoperatively, one patient had delayed wound healing, two developed biochemical pancreatic fistulae, one experienced lymphatic leakage, the former caused by heat damage of the pancreatic tissues, the latter by cutting lymphatic vessels in the mesentery or removing the local lymph nodes during the process of separating the superior mesenteric vein, and one was re-operated on for an intervening intestinal fistulae. Postoperative enhanced CT scans revealed a significant improvement in abdominal varix in the patients with patent bypass, and at the 1-year postoperative follow-up, enhanced CT scans of six patients showed that the long axis of the spleen was reduced by ≥ 2 cm.

CONCLUSIONS

MRB can effectively reduce visceral venous pressure in patients with PVCT. It is feasible to determine the PVCT type according to the extent of involvement and to choose individualized visceral side revascularization performances.

Intrahepatic portal venous systems in adult patients with cavernous transformation of portal vein: Imaging features and a new classification

BACKGROUND

Cavernous transformation of the portal vein (CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to investigate the imaging features of intrahepatic portal vein in adult patients with CTPV and establish the relationship between the manifestations of intrahepatic portal vein and the progression of CTPV.

METHODS

We retrospectively analyzed 14 CTPV patients in Beijing Tsinghua Changgung Hospital. All patients underwent both direct portal venography (DPV) and computed tomography angiography (CTA) to reveal the manifestations of the portal venous system. The vessels measured included the left portal vein (LPV), right portal vein (RPV), main portal vein (MPV) and the portal vein bifurcation (PVB).

RESULTS

Nine males and 5 females, with a median age of 40.5 years, were included in the study. No significant difference was found in the diameters of the LPV or RPV measured by DPV and CTA. The visualization in terms of LPV, RPV and PVB measured by DPV was higher than that by CTA. There was a significant association between LPV/RPV and PVB/MPV in term of visibility revealed with DPV (P = 0.01), while this association was not observed with CTA. According to the imaging features of the portal vein measured by DPV, CTPV was classified into three categories to facilitate the diagnosis and treatment.

CONCLUSIONS

DPV was more accurate than CTA for revealing the course of the intrahepatic portal vein in patients with CTPV. The classification of CTPV, that originated from the imaging features of the portal vein revealed by DPV, may provide a new perspective for the diagnosis and treatment of CTPV.

REX SHUNT IN CHILDREN: COULD DYSFUNCTION BE PROGNOSED? A RETROSPECTIVE ANALYSIS

OBJECTIVE

The aim: To analyze retrospectively our experience of Rex shunt in children with symptomatic portal hypertension, its effect on hypersplenism regression and varices eradication, assess shunt survival and investigate risk factors, that could lead to shunt dysfunction and thrombosis.

PATIENTS AND METHODS

Materials and methods: 24 children (16 males, 8 females) ,with portal hypertension included into the study. All surgeries were performed within single center in a period from January 2010 to March 2022. Follow up period was 6.75±1.19 years.

RESULTS

Results: Age at diagnosis was 5.39±0.64 years. 5 (20.8%) had umbilical catheter in anamnesis. 16 (66.7%) manifested bleeding episodes as the first sign of portal hypertension. 9 (37.5%) of children manifested severe hypersplenism. Age at Rex shunting was 7.5±0.7 years. In 7 (31.8%) cases Rex shunt thrombosis occurred. 1 successful thrombectomy and 6 splenorenal shunting were performed. Kaplan-Meyer analysis showed Rex shunt survival 0.670 (95%CI 0.420-0.831). Logistic regression model indicated thrombocytes count (p=0.0423) and cytopenia (p=0.0272) as factors that could influence shunt thrombosis. Follow-up group included 18 patients. Spleen volume regression became significant by 1 p/o year p<0,05, thrombocytes significant increasement reached in 1 p/o months (p<0.01), varices involution was achieved by 1 p/o year (p<0,001).

CONCLUSION

Conclusions: Rex shunt effectiveness in study group was 70.9%., shunt survival assessed 0.670 (95%CI 0.420-0.831). Rex shunt was effective in bleeding prophylaxis in all patients of follow up group. Preoperative thrombocytes count (p=0.0423) and cytopenia (p=0.0272) were detected as factors that could influence shunt thrombosis, that is to be considered in RS preoperative period and require following studies.

Optimal Rex shunt procedures as a treatment for pediatric extrahepatic portal hypertension

PURPOSE

To assess the long-term results after Rex bypass (RB) shunt and Rex transposition (RT) shunt and determine the optimal approach.

METHODS

Between 2010 and 2019, traditional RB shunt was performed in 24 patients, and modified RT shunt was performed in 23 children with extrahepatic portal hypertension (pHTN). A retrospective study was conducted based on comparative symptoms, platelet counts, color Doppler ultrasonography and computed tomographic portography of the portal system, and gastroscopic gastroesophageal varices postoperatively. The portal venous pressure was evaluated intraoperatively.

RESULTS

The operation in the RB group was notably more time-consuming than that in the RT group (P < 0.05). Compared to RT shunt, the reduction in gastroesophageal varix grading, the increases in platelets, and the caliber of the bypass were greater in the RB group (P < 0.05). Although not statistically significant, higher morbidity of surgical complications was found after RT shunt (17.4%) compared with RB shunt (8.3%) with patency rates of 82.6 and 91.7%, respectively. Additionally, patients exhibited a lower rate of rebleeding under the RB procedure (12.5%) than under the RT procedure (21.7%).

CONCLUSIONS

The RT procedure is an alternative option for the treatment of pediatric extrahepatic pHTN, and RB shunt is the preferred procedure in our center.

Sonographic features of umbilical vein recanalization for a Rex shunt on cavernous transformation of portal vein in children

BACKGROUND

The Rex shunt was widely used as the preferred surgical approach for cavernous transformation of the portal vein (CTPV) in children that creates a bypass between the superior mesenteric vein and the intrahepatic left portal vein (LPV). This procedure can relieve portal hypertension and restore physiological hepatopetal flow. However, the modified procedure is technically demanding because it is difficult to make an end-to-end anastomosis of a bypass to a hypoplastic LPV. Many studies reported using a recanalized umbilical vein as a conduit to resolve this problem. However, the feasibility of umbilical vein recanalization for a Rex shunt has not been fully investigated.

AIM

To investigate the efficacy of a recanalized umbilical vein as a conduit for a Rex shunt on CTPV in children by ultrasonography.

METHODS

A total of 47 children who were diagnosed with CTPV with prehepatic portal hypertension in the Second Hospital, Cheeloo College of Medicine, Shandong University, were enrolled in this study. Fifteen children received a recanalized umbilical vein as a conduit for a Rex shunt surgery and were enrolled in group I. Thirty-two children received the classic Rex shunt surgery and were enrolled in group II. The sonographic features of the two groups related to intraoperative and postoperative variation in terms of bypass vessel and the LPV were compared.

RESULTS

The patency rate of group I (60.0%, 9/15) was significantly lower than that of group II (87.5%, 28/32) 7 d after (on the 8^th d) operation (P < 0.05). After clinical anticoagulation treatment for 3 mo, there was no significant difference in the patency rate between group I (86.7%, 13/15) and group II (90.6%, 29/32) (P > 0.05). Moreover, 3 mo after (at the beginning of the 4^th mo) surgery, the inner diameter significantly widened and flow velocity notably increased for the bypass vessels and the sagittal part of the LPV compared to intraoperative values in both shunt groups (P < 0.05). However, there was no significant difference between the two surgical groups 3 mo after surgery (P > 0.05).

CONCLUSION

For children with hypoplastic LPV in the Rex recessus, using a recanalized umbilical vein as a conduit for a Rex shunt may be an effective procedure for CTPV treatment.

Effects of Rex-bypass shunt on the cavernous transformation of the portal vein in children: evaluation by the color Doppler ultrasonography

BACKGROUND

The study was to investigate the role of color Doppler ultrasonography in the evaluation of the effect of Rex-bypass shunt on the cavernous transformation of the portal vein (CTPV) in children.

METHODS

Fifty children with symptomatic extrahepatic portal hypertension who received Rex-bypass shunt were retrospectively reviewed, and they were diagnosed with CTPV by ultrasonography. The clinical characteristics were analyzed before and after operation.

RESULTS

Forty-five patients received color Doppler ultrasonography at 6 months after surgery, and good patency in the bypass vessels was displayed. The platelet count significantly increased (P < 0.001) and the esophagogastric varices were improved significantly (p < 0.001). The patency of bypass vessels on color Doppler ultrasonography was consistent with the changes in the platelet count and the degree of esophagogastric varices on gastroscopy before and after operation. The diameter of bypass vessels at 6 months was slightly larger than that at 7 days after operation, and there was no significant difference in blood flow velocity between two time points (P = 0.507).

CONCLUSIONS

Color Doppler ultrasonography can display the patency, diameter, and flow velocity of bypass vessels. It plays an important role in evaluating the effect of Rex-bypass shunt on the CTPV.

Zero ischemia laparoscopic microwave ablation assisted enucleation vs. laparoscopic partial nephrectomy in clinical T1a renal tumor: a randomized clinical trial

Background

The study aims to evaluate efficiency, safety and the functional outcomes of zero ischemia laparoscopic microwave ablation assisted tumor enucleation (LMWATE) in comparison with laparoscopic partial nephrectomy (LPN) for cT1a renal tumors.

Methods

A prospective randomized controlled trial on cT1a renal tumor patients treated by laparoscopic nephron sparing surgeries between October 2014 to September 2017 was conducted. Tumor enucleation was performed in the LMWATE group after microwave ablation (MWA) without hilar clamping. The endpoint was the affected kidney's change of GFR measured by renal scintigraphy at the 3rd month and 12th month postoperatively. All the patients were followed up for at least 12 months. The Student t-test, Wilcoxon rank sum tests and Pearson Chi-square or Fisher exact were applied to analyse data.

Results

The number of patients enrolled in the LMWATE group and LPN group were 90 and 93 respectively. Patients in the LPN group showed much more decline of effect kidney glomerular filtration rate at 3 months (10.3 vs. 17.4, P<0.001) and 12 months postoperatively (8.8 vs. 10.2, P=0.023) when compared to the LMWATE group. Additionally, in the LMWATE group, considerably shorter median operation duration (91 vs. 112 minutes, P<0.001), lower median estimated blood loss (82.5 vs. 117.5 mL, P<0.001) and shorter hospital stay (5.5 vs. 6 days, P=0.013) were observed but with similar postoperative complications in both groups. There was no positive margin or local recurrence in both groups.

Conclusions

Zero ischemia LMWATE may provide better preservation of renal function, decrease operative time and blood loss compared to LPN with similar complication rates.

Cavernous Transformation of Portal Vein in the Setting of Protein C and Anti-thrombin III Deficiency

Cavernous transformation of the portal vein (CTPV), also known as portal cavernoma, is a sequelae of thrombosis in the portal vein causing its occlusion and portal hypertension. The etiology, however, remains unknown. Gastroesophageal variceal bleeding, splenomegaly, portosystemic collaterals, and ultimate hematologic abnormalities are among the prominent clinical features. Among the causes, predisposing an individual to CTPV is natural anticoagulant protein C and antithrombin III deficiencies. Determination of the etiology of CTPV may also give a direction toward the management plan to not only relieve the patient of the already developed complications but also to treat the primary cause of the pathology 

We discuss a case of a nine-year-old male child diagnosed as CTPV secondary to protein C and antithrombin III deficiency who was treated symptomatically for anemia and varices and was referred for transjugular intrahepatic portosystemic shunt (TIPS).

Combined Rex-bypass shunt with pericardial devascularization alleviated prehepatic portal hypertension caused by cavernomatous transformation of portal vein

OBJECTIVE

To evaluate the effects of combined Rex-bypass shunt and pericardial devascularization on prehepatic portal hypertension secondary to cavernomatous transformation of portal vein (CTPV).

METHODS

Forty-two patients aged from 3 years to 49 years (divided into 3 groups), 26 cases male and 16 female, with prehepatic vascular hepertention were treated with Rex-bypass shunt combined with pericardial devascularization. In each patient, preoperative assessment included ultrasound and computed tomographic angiography of the portal vein and blood analysis. The procedure was Rex-bypass shunt (with or without graft), and patients with moderate or severe gastroesophageal varices required additional paraesophagogastric devascularization. Splenectomy or subtotal splenectomy was performed if combined hypersplenism co-existed. All data were analyzed retrospectively.

RESULTS

No intraoperative death occurred, blood routine analysis improved (P < 0.05), the blood flow velocity (P < 0.05) and diameter (P < 0.05) of the left portal vein (LPV) significantly increased, the esophageal and gastric varices significantly relieved in 34 patients (P < 0.05), and better effects of earlier operations were demonstrated than the delayed ones (P < 0.05). During the period of follow-up from 6 to 64 months, the overall patency rate was 85.7% and the younger the age the better of the effect.

CONCLUSION

Rex-bypass shunt combined with pericardial devascularization is a safe and effective procedure for prehepatic portal hypertension caused by CTPV.