Esophageal and gastric vasculature in children with extrahepatic portal hypertension: evaluation by intravenous CT portography

Comparison of sequential CT arterioportography-arteriosplenography with standard cross-sectional imaging and endoscopy in children with portal hypertension

In this study the diagnostic capability and additional value of sequential CT arterioportography–arteriosplenography (CT AP–AS) in comparison to standard cross-sectional imaging and upper gastrointestinal endoscopy (UGE) in pediatric portal hypertension (PH) was analyzed. Patients with clinical signs of PH who underwent CT AP–AS in combination with additional contrast-enhanced magnetic resonance imaging (CE-MR) and/or contrast-enhanced computed tomography (CE-CT) were included. Two radiologists reviewed independently imaging regarding the capability to prove patency of (1) extrahepatic and intrahepatic main stem portal vein (PV), (2) intrahepatic PV system and (3) splenomesenteric venous axis. Imaging was reviewed for detection of abdominal varices and results were compared to UGE. Main venous supply of varices (PV and/or splenic vein system) and splenorenal shunting were evaluated. 47 imaging studies (20 CT AP-AS, 16 CE-MR, 11 CE-CT) and 12 UGE records of 20 patients were analyzed. CT AP–AS detected significantly more splenorenal shunts (p = 0.008) and allowed more confident characterization of the extra-/intrahepatic PV-system and splenomesenteric veins in comparison to CE-MR (p < 0.001). Extra- and intrahepatic PV-system were significantly more confidently assessed in CT AP–AS than in CE-CT (p = 0.008 and < 0.001 respectively). CT AP–AS was the only modality that detected supply of varices and additional gastric/duodenal varices. In this retrospective study CT AP–AS was superior to standard cross-sectional imaging concerning confident assessment of the venous portosplenomesenteric axis in pediatric patients. CT AP–AS detected additional varices, splenorenal shunting and supply of varices.

Value of preoperative computed tomography for meso-Rex bypass in children with extrahepatic portal vein obstruction

Background

Extrahepatic portal vein obstruction (EHPVO) is the most important cause of hematemesis in children. Intrahepatic left portal vein and superior mesenteric vein anastomosis, also known as meso-Rex bypass (MRB), is becoming the gold standard treatment for EHPVO. We analyzed the value of preoperative computed tomography (CT) in determining whether MRB is feasible in children with EHPVO.

Results

We retrieved data on 76 children with EHPVO (50 male, 26 female; median age, 5.9 years) who underwent MRB (n = 68) or the Warren procedure (n = 8) from 2013 to 2019 and retrospectively analyzed their clinical and CT characteristics. The Rex recess was categorized into four subtypes (types 1–4) depending on its diameter in CT images. Of all 76 children, 7.9% had a history of umbilical catheterization and 1.3% had leukemia. Sixteen patients (20 lesions) had associated malformations. A total of 72.4% of Rex recesses could be measured by CT, and their mean diameter was 3.5 ± 1.8 mm (range 0.6–10.5 mm). A type 1, 2, 3, and 4 Rex recess was present in 9.2%, 53.9%, 11.8%, and 25.0% of patients, respectively. MRB could be performed in patients with types 1, 2, and 3, but those with type 4 required further evaluation. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of CT were 100%, 83.8%, 42.1%, 100%, and 85.5%, respectively.

Conclusions

Among the four types of Rex recesses on CT angiography, types 1–3 allow for the performance of MRB.

Multimodality imaging of the Meso-Rex bypass

Extrahepatic portal vein obstruction (EHPVO) is the most common cause of upper gastrointestinal bleeding in children. It is defined as thrombosis of the extrahepatic portal vein with or without extension to the intrahepatic portal veins. The Meso-Rex shunt is the gold standard treatment in children with favorable anatomy since it restores physiological portal liver reperfusion. This is achieved by rerouting the splanchnic venous blood through an autologous graft from the superior mesenteric vein (SMV) into the Rex recess of the left portal vein, curing portal hypertension by doing so. General and hepatobiliary radiologists must be familiar with multimodality imaging appearances of EHPVO and with the role of imaging in identifying suitable candidates for Meso-Rex bypass surgery. Imaging might also detect complications of this procedure, some of which might be treated via interventional radiology.

Computed tomography in evaluating gastroesophageal varices in patients with portal hypertension: A meta-analysis

AIMS

Gastroesophageal varices (GOV) is a common complication in patients with portal hypertension. We conducted a meta-analysis in attempt to evaluate the diagnostic accuracy of computed tomography (CT) as a noninvasive imaging tool for identifying GOV in reference to esophagogastroduodenoscopy (EGD).

METHODS

A systemic literature search of multiple databases were conducted to identify articles that investigated the diagnostic performance of CT for GOV, while employing EGD as reference standard. A 2×2 table was conducted according to the available published data for both esophageal varices (EV) and gastric varices (GV) as individual subgroups. The following indices were calculated: pooled sensitivity and specificity, positive and negative likelihood ratio, diagnostic odds ratio, and area under receiver operating characteristics. All statistical analyses were conducted via STATA13.0 and RevMan5.3.

RESULTS

A total of 11 studies were included in this meta-analysis, 10 articles evaluated the diagnostic accuracy of CT for EV (807 subjects) and 7 articles for GV (583 subjects). The pooled sensitivity and specificity for identifying EV were 0.896 (95% CI, 0.841-0.934) and 0.723 (95% CI, 0.644-0.791), respectively, with an AUROC of 0.86. The pooled sensitivity and specificity for identifying GV were 0.955 (95% CI, 0.903-0.980) and 0.658 (95% CI, 0.433-0.829), respectively, with an AUROC of 0.95. A subgroup analysis suggested varying CT technology could serve as a potential source of heterogeneity between included studies. A Deek's funnel plot indicated a low probability for publication bias.

CONCLUSION

Computed tomography could potentially replace EGD as a primary screening tool for diagnosing GOV, however results should be interpreted with caution given its suboptimal specificity.

The cost of screening esophageal varices: traditional endoscopy versus computed tomography

OBJECTIVE

Under current guidelines, patients diagnosed with cirrhosis are to undergo initial and continued screening endoscopy for esophageal varices throughout the course of disease. Recent literature suggests that computed tomography (CT) of the abdomen is adequately sensitive for detecting grade 3 varices, those in need of immediate intervention. This study presents a cost comparison of traditional endoscopy versus CT of the abdomen.

METHODS

Using TreeAge Pro software, a budget impact cost model was created for a hypothetical managed care organization covering 1 million lives over a 10-year period. Incidence figures for cirrhosis and the progression of esophageal varices were applied to the patient population. National Medicare reimbursement costs were used to compare screening with traditional endoscopy versus CT. Costs utilizing screening with combined endoscopy and CT were also examined.

RESULTS

The results of comparing screening paradigms under a budget impact cost model results in an outcome measure termed "per-member, per-month" (PMPM) cost of implementing a new strategy. Computed tomography was the least expensive modality with an average 10-year cost per screened patient of $1097.30 and PMPM of $0.03. Endoscopy was the most expensive modality with an average 10-year cost per screened patient of $1464.89 and PMPM of $0.04.

CONCLUSION

Computed tomography has been shown to be sensitive in detecting esophageal varices and now less costly to implement in screening. The cost of esophageal rupture in endoscopy and the less costly risk of contrast reaction as well as radiation exposure in CT of the abdomen should be considered when developing a screening paradigm.

Portal hypertension: A critical appraisal of shunt procedures with emphasis on distal splenorenal shunt in children

Background:

Extrahepatic portal venous obstruction (EHPVO) is the most common cause of pediatric portal hypertension. We analyzed the investigative protocol and results of portosystemic shunts in this group of patients.

Materials and Methods:

A total of 40 consecutive children aged below 12 years operated with a diagnosis of extra-hepatic portal hypertension formed the study group. Historical data and clinical data were collected. All patients underwent upper gastrointestinal endoscopy, ultrasound Doppler and computed tomographic portogram pre-operatively and post-operatively. Results with respect to shunt patency, hypersplenism and efficacy of different radiological investigations were collected.

Results:

A total of 40 patients, 28 boys and 12 girls constituted the study group. Lienorenal shunt (LRS) was performed in 14 patients; distal splenorenal shunt in 21 patients and side-to-side lienorenal shunt in 4 patients, inferior mesenteric renal shunt was performed in 1 patient. Follow-up ranged from 36 to 70 months. At a minimum follow-up of 3 years, 32 (80%) patients were found to have patent shunts. Patent shunts could be visualized in 30/32 patients with computer tomographic portogram (CTP) and 28/32 with ultrasound. Varices regressed completely in 26/32 patients and in the rest incomplete regression was seen. Spleen completely regressed in 19/25 patients. Hypersplenism resolved in all patients with patent shunts.

Conclusions:

Portosystemic shunting in children with EHPVO is a viable option. While long-term cure rates are comparable with sclerotherapy, repeated hospital visits are reduced with one time surgery. Pre-operative and post-operative assessment can be performed with complimentary use of ultrasound, CTP and endoscopy.

Surgery as primary prophylaxis from variceal bleeding in patients with extrahepatic portal venous obstruction

BACKGROUND AND AIM

In patients with extrahepatic portal venous obstruction (EHO), death is usually due to variceal bleeding. This is more so in developing countries where there is a lack of tertiary health-care facilities and blood banks. Prophylactic operations in cirrhotics have been found to be deleterious. In contrast, patients with EHO have well-preserved liver function, and we therefore investigated the role of prophylactic surgery to prevent variceal bleeding.

METHODS

Between 1976 and 2010, we operated on selected patients with EHO, who had no history of variceal bleeding but had "high-risk" esophagogastric varices or severe portal hypertensive gastropathy and/or hypersplenism, and came from remote areas with poor access to tertiary health care. Following surgery, these patients were prospectively followed up with regard to mortality, variceal bleeding, encephalopathy, and liver function.

RESULTS

A total of 114 patients (67 males; mean age 19 years) underwent prophylactic operations (proximal splenorenal shunts 98 [86%]; esophagogastric devascularization 16). Postoperative mortality was 0.9%. Among 89(79%) patients who were followed up (mean 60 months), hypersplenism was cured, and six (6.7%) developed variceal bleeding. The latter were managed successfully by endoscopic sclerotherapy. No patient developed overwhelming post-splenectomy sepsis or encephalopathy, and 90% were free of symptoms.

CONCLUSION

In patients with EHO, prophylactic surgery is fairly safe and prevents variceal bleeding in ∼ 94% of patients with no occurrence of portosystemic encephalopathy. Patients with EHO who have not bled but have high-risk varices and/or hypersplenism, and poor access to medical facilities should be offered prophylactic operations.

Gluing gastric varices in 2012: lessons learnt over 25 years

Bleeding from gastric varices (GV) continues to pose a challenge to the endoscopist and no consensus has been reached on the best way for treating these patients. Gastric variceal obturation (GVO) with the tissue adhesive, N-2-butyl-cyanoacrylate (NBC), is considered the treatment of first-choice for this condition in most parts of the world. The liquid monomer polymerizes into a solid cast, obturating the vessel within 10-20 s of coming in contact with ionic solutions such as blood. Gastric variceal obturation achieves hemostasis in over 90% of patients with active bleeding, eradicates GV in over 80% of these patients, and re-bleeding occurs in 3-30%. These results are comparable with those of transjugular intrahepatic portosystemic shunting (TIPS; over 90% hemostasis in acute bleeding with re-bleeding in 15-30%). Though, there has been no direct comparison with GVO, balloon-occluded retrograde transvenous obliteration of GV (BRTO) achieves near 100% obliteration with recurrence in 0-10% and is superior to TIPS for hemostasis in active bleeding when used in combination with transcatheter sclerotherapy. Several complications have been described for GVO including thromboembolic complications which occur in 0.5-4.3% and may be devastating in some. Many of the complications and the variability in results of GVO can be attributed to variations in injection technique. The use of a standardized injection technique has been reported to achieve 100% hemostasis and obliteration with 6.9% re-bleeding and no embolic complications. Gastric variceal obturation with NBC continues to be the first-choice therapy for GV bleeding outside Japan. Adherence to a standard injection technique will maximize hemostasis and eradication of GV while minimizing complications of therapy.

Pre- and postoperative imaging and interventions for the meso-Rex bypass in children and young adults

The meso-Rex bypass is a physiological and anatomical bypass procedure for relief of extrahepatic portal vein obstruction and restoration of mesenteric venous return to the liver. Most patients who are candidates for the bypass are children or young adults with portal hypertension and hypersplenism secondary to cavernous transformation of the portal vein. Most frequently, the bypass utilizes an autologous venous graft to connect the intrahepatic left portal vein to the infrapancreatic superior mesenteric vein (SMV) re-establishing first-pass portal perfusion. We describe the preoperative imaging of the 92 bypass candidates, the surgical anatomy as reflected in postoperative imaging, and the imaging of bypass complications at our institution.Preoperative imaging with US, CT and MR is directed to demonstrate patency and size of the left portal vein and SMV, to define the extent of cavernous transformation and splanchnic collaterals, and to assess for any associated abdominal vascular or solid organ abnormalities. Postoperative imaging is aimed at diagnosing meso-Rex bypass stenosis or occlusion and the interventional management of these complications.

Detection and grading of esophageal varices on liver CT: comparison of standard and thin-section multiplanar reconstructions in diagnostic accuracy

OBJECTIVE

The objective of our study was to evaluate the performance of liver CT in the diagnosis of esophageal varices in patients with cirrhosis and to determine whether thin-section multiplanar reconstructions (MPRs) improve accuracy.

MATERIALS AND METHODS

We identified 109 patients with cirrhosis who underwent endoscopy within 10 weeks after dual-phase liver MDCT supplemented with thin-section axial and coronal portal venous phase reconstructions. Two blinded radiologists independently evaluated each CT examination for the presence and sizes of varices using standard 5-mm axial versus 1- to 3-mm multiplanar images in separate sessions. Sensitivity, specificity, and predictive value calculations and receiver operating characteristic analysis were performed using endoscopy as the reference standard. Interobserver variability and correlation of CT size to variceal grade were assessed.

RESULTS

Twenty-six cases of high-risk esophageal varices were identified; all except two were detected on CT by one of the readers on standard 5-mm images. For both readers, sensitivity and negative predictive value (NPV) for the discrimination of high-risk varices using a criterion of 2 mm or greater were nearly the same for the standard 5-mm images versus the 1- to 3-mm multiplanar images (sensitivity and NPV: reader 1, 96% and 98% vs 96% and 99%; reader 2, and 89% and 95% vs 89% and 96%, respectively). Standard 5-mm images yielded a lower specificity for high-risk esophageal varices than the thin-section multiplanar images, and this difference was statistically significant for reader 2. Substantial interobserver agreement was noted for both esophageal varices detection and size measurements.

CONCLUSION

Standard liver CT is sensitive for the detection of high-risk varices and deserves further investigation as a potential cost-effective screening tool for the evaluation of patients with cirrhosis. The addition of 1- to 3-mm MPRs may increase specificity for risk stratification based on size measurements.

CT angiography in pediatric extremity trauma: preoperative evaluation prior to reconstructive surgery

Computed tomographic angiography (CTA) is a noninvasive modality for evaluating the vascular system and planning treatment strategies. The goal of this study was to validate the clinical utility of CTA in assessment of suspected pediatric extremity traumatic vascular injury, prior to emergent and delayed reconstructive surgery. A retrospective review was performed of all operative patients under 18 years of age who underwent multidetector-row CTA for evaluation of suspected extremity vascular injury. Parameters investigated included age, type of injury, referral source, temporal relationship between the injury and the CTA, CTA findings, operations performed, intraoperative findings, and clinical outcome. Between January 2002 and September 2005, 10 pediatric patients (6 males/4 females; mean age 8 years old, range 3-17) sustained either blunt (N = 8) or penetrating (N = 2) trauma and underwent CTA of the upper (N = 5) or lower extremities (N = 5). A total of 30% (3/10) of patients were referred from the emergency department acutely, 50% (5/10) were referred from the inpatient wards subacutely, and 20% (2/10) were referred from the outpatient clinics electively. Half (N = 5) underwent CTA to evaluate need for vascular repair, whereas half (N = 5) underwent CTA to evaluate local vasculature for flap reconstruction. Overall, 40% (4/10) of CTA findings were normal, whereas 60% (6/10) revealed traumatic vascular injuries. Pertinent nonvascular findings included soft tissue defects (60%, 6/10), fractures (40%, 4/10), and contracture deformities (20%, 2/10). In all cases, procedures were completed without complications, and intraoperative findings confirmed those from CTA. At a mean follow-up of 28 months, all injuries have healed without complications. CTA is a reliable noninvasive modality to evaluate pediatric patients with suspected traumatic extremity vascular injury and to plan treatment strategies for both vascular repair and extremity reconstruction.

Esophageal varices in cirrhotic patients: evaluation with liver CT

OBJECTIVE

The objective of this study was to evaluate the performance of routine helical liver CT in the detection and grading of esophageal varices in cirrhotic patients.

MATERIALS AND METHODS

A total of 67 consecutive cirrhotic patients who underwent both upper endoscopy and helical liver CT within a 4-week interval were evaluated. The CT protocol included unenhanced, arterial, and portal phases with a collimation of 7-7.5 mm. Two blinded abdominal imagers (6 and 7 years' experience) retrospectively interpreted all CT images to detect the presence of esophageal varices on a 5-point confidence scale and measure the largest varix identified. Receiver operating characteristic (ROC) curve analysis was performed, and the correlation between CT measurements and endoscopic grading, the reference standard, was assessed.

RESULTS

The variceal detection rates for the observers was 92% (11/12) and 92% (11/12) for large (i.e., clinically significant) varices, 53% (16/30) and 60% (18/30) for small varices, and 64% (27/42) and 69% (29/42) for all varices. The area under the ROC curve for the detection of esophageal varices of any size was 0.77 (observer 1) and 0.80 (observer 2). CT variceal grading showed a strong correlation with endoscopic grading for both observers (p < or = 0.001). Using a variceal diameter threshold of 3 mm on CT, sensitivity, specificity, and accuracy for distinguishing large esophageal varices from small or no varices were 92% (11/12), 84% (46/55), and 85% (57/67), respectively, for both observers.

CONCLUSION

Liver CT is useful for the detection and grading of esophageal varices. A diameter of 3 mm may be an appropriate screening threshold for large clinically significant varices.

Extrahepatic portal vein morphology in children with extrahepatic portal hypertension assessed by 3-dimensional computed tomographic portography: a new etiology of extrahepatic portal hypertension

BACKGROUND/PURPOSE

The cause of extrahepatic portal hypertension in children has not been clarified. Our aim was to determine the morphological features of the extrahepatic portal vein in children with extrahepatic portal hypertension by 3-dimensional computed tomographic portography and to clarify the etiology of this disorder.

MATERIALS AND METHODS

Six patients ranging in age from 10 to 18 years (median age, 12.8 years) who had portal hypertension presented with hematemesis. They underwent intravenous computed tomographic portography using a helical computed tomography scanner and 3-dimensional image reconstruction.

RESULTS

The extrahepatic portal vein was visualized in all patients by 3-dimensional computed tomographic portography. None of the patients showed extrahepatic portal vein obstruction or cavernous transformation. All patients had a tortuous eta-shaped extrahepatic portal vein, and a line could be drawn through the flexures of the portal vein to the hepatic hilum.

CONCLUSION

In children, extrahepatic portal hypertension is not caused by extrahepatic portal vein obstruction and may be of embryological origin.

MDCT angiography of pediatric vascular diseases of the abdomen, pelvis, and extremities

Multi-detector-row computed tomography (MDCT) enables rapid, noninvasive, high-resolution, and three-dimensional imaging of pediatric vascular diseases. In this paper, we explore the adaptation of the MDCT angiographic principles to pediatric patients for vascular diseases of the abdomen, pelvis, and extremities. Special emphasis is placed on the practical aspects of how to perform these studies. Optimizations of scan parameters, contrast medium usage, radiation dose, and three-dimensional image processing are discussed in detail. We provide practical guidance on how to choose between MR angiography and CT angiography. Finally, we review important pediatric vascular diseases, categorized into traumatic injuries, inherited vascular diseases, congenital vascular diseases, vasculitides, and surgical planning and assessment. In each category, we discuss how CT angiography can be tailored to maximize its clinical benefits.