Non-cirrhotic portal hypertension: an imaging review

Noninvasive diagnosis of liver cirrhosis: qualitative and quantitative imaging biomarkers

A diagnosis of cirrhosis initiates a shift in the management of chronic liver disease and affects the diagnostic workflow and treatment decision of primary liver cancer. Liver biopsy remains the gold standard for cirrhosis diagnosis, but it is invasive and susceptible to sampling bias and observer variability. Various qualitative and quantitative imaging biomarkers based on ultrasound, CT and MRI have been proposed for noninvasive diagnosis of cirrhosis. Qualitative imaging features are easy to apply but have moderate diagnostic sensitivity. Elastography techniques allow quantitative assessment of liver stiffness and are highly accurate for cirrhosis diagnosis. Ultrasound elastography are widely used in clinical practice, while MR elastography has narrower availability. Although not applicable in clinical practice yet, other quantitative imaging features, including liver surface nodularity, linear and volumetric measurement, extracellular volume fraction, liver enhancement on hepatobiliary phase, and parameters derived from diffusion-weighted imaging, can provide additional information of liver morphology, perfusion, and function, thus may increase diagnosis performance. The introduction of radiomics and deep learning has further improved diagnostic accuracy while reducing subjectivity. Several imaging features may also help to assess liver function and outcomes in patients with cirrhosis. In this review, we summarize the qualitative and quantitative imaging biomarkers for noninvasive cirrhosis diagnosis, and the assessment of liver function and outcomes, and discuss the challenges and future directions in this field.

Recent Advances in the Pathogenesis and Clinical Evaluation of Portal Hypertension in Chronic Liver Disease

In chronic liver disease, hepatic stellate cell activation and degeneration of liver sinusoidal endothelial cells lead to structural changes, which are secondary to fibrosis and the presence of regenerative nodules in the sinusoids, and to functional changes, which are related to vasoconstriction. The combination of such changes increases intrahepatic vascular resistance and causes portal hypertension. The subsequent increase in splanchnic and systemic hyperdynamic circulation further increases the portal blood flow, thereby exacerbating portal hypertension. In clinical practice, the hepatic venous pressure gradient is the gold-standard measure of portal hypertension; a value of ≥10 mm Hg is defined as clinically significant portal hypertension, which is severe and is associated with the risk of liver-related events. Hepatic venous pressure gradient measurement is somewhat invasive, so evidence on the utility of risk stratification by elastography and serum biomarkers is needed. The various stages of cirrhosis are associated with different outcomes. In viral hepatitis-related cirrhosis, viral suppression or elimination by nucleos(t)ide analog or direct-acting antivirals results in recompensation of liver function and portal pressure. However, careful follow-up should be continued, because some cases have residual clinically significant portal hypertension even after achieving sustained virologic response. In this study, we reviewed the current and future prospects for portal hypertension.

The Portal Vein: A Comprehensive Review

Radiologists are familiar with the appearances of a normal portal vein; variations in its anatomy are commonplace and require careful consideration due to the implications for surgery. These alterations in portal vein anatomy have characteristic appearances that are clearly depicted on CT, MR, and US images. Similarly, there are numerous congenital and acquired disorders of the portal vein that are deleterious to its function and can be diagnosed by using imaging alone. Some of these conditions have subtle imaging features, and some are conspicuous at imaging but poorly understood or underrecognized. The authors examine imaging appearances of the portal vein, first by outlining the classic and variant anatomy and then by describing each of the disorders that impact portal vein function. The imaging appearances of portal vein abnormalities discussed in this review include (a) occlusion from and differentiation between bland thrombus and tumor in vein and the changes associated with resultant hepatic artery buffer response changes, cavernous transformation of the portal vein, and portal biliopathy; (b) ascending thrombophlebitis of the portal vein (pylephlebitis); (c) portal hypertension and its causes and sequelae; (d) the newly described disease entity portosinusoidal vascular disorder; and (e) intra- and extrahepatic shunts of the portal system, both congenital and acquired (including Abernethy malformations), and the associated risks. Current understanding of the pathophysiologic processes of each of these disorders is considered to aid the approach to reporting. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Spontaneous hepatic arterioportal fistula in extrahepatic portal vein obstruction: Combined endovascular and surgical management

Hepatic arterioportal fistulae are abnormal communications between the hepatic artery and portal vein. They are reported to be congenital or acquired secondary to trauma, iatrogenic procedures, hepatic cirrhosis, and hepatocellular carcinoma, but less likely to occur spontaneously. Extrahepatic portal venous obstruction (EHPVO) can lead to pre-hepatic portal hypertension. A spontaneous superimposed hepatic arterioportal fistula can lead to pre-sinusoidal portal hypertension, further exacerbating its physiology. This report describes a young woman with long-standing EHPVO presenting with repeated upper gastrointestinal variceal bleeding and symptomatic hypersplenism. Computed tomography scan demonstrated a cavernous transformation of the portal vein and a macroscopic hepatic arterioportal fistula between the left hepatic artery and portal vein collateral in the central liver. The hepatic arterioportal fistula was associated with a flow-related left hepatic artery aneurysm and a portal venous collateral aneurysm proximal and distal to the fistula, respectively. Endovascular coiling was performed for the hepatic arterioportal fistula, followed by proximal splenorenal shunt procedure. This case illustrates an uncommon association of a spontaneous hepatic arterioportal fistula with EHPVO and the utility of a combined endovascular and surgical approach for managing multifactorial non-cirrhotic portal hypertension in such patients.

Attach importance to the individualized treatment of adult portal hypertension based on etiology and pathogenesis: A review

There are many factors that can cause portal hypertension and secondary symptoms such as ascites, splenomegaly, and variceal hemorrhage, can seriously affect patients' quality of life and even threaten their lives. In this paper, we summarize various causes of portal hypertension based on etiology and pathogenesis and give individualized treatment strategies in order to remind clinicians to pay attention to the identification of different causes and select corresponding treatment, so that patients are provided with the optimal treatment strategies and benefit from them.

Imaging features facilitate diagnosis of porto-sinusoidal vascular disorder

OBJECTIVES

Porto-sinusoidal vascular disorder (PSVD) is a recently defined vascular liver disease. Since diagnosis remains challenging, we aimed to evaluate radiological features that are distinct between PSVD and cirrhosis.

METHODS

Clinical, laboratory, and radiological parameters (CT/MRI) of patients with histologically-confirmed PSVD vs. cirrhosis vs. non-cirrhotic parenchymal liver disease were retrospectively evaluated.

RESULTS

Sixty-three PSVD, 155 cirrhosis, and 41 non-cirrhotic patients were included. As compared to cirrhosis, PSVD patients were younger and had lower HVPG, liver stiffness, and MELD. Routine clinical and imaging findings indicative of portal hypertension were similarly common. Intrahepatic portal tract abnormalities (49% vs. 15%; p < 0.001), FNH-like lesions (30% vs. 1%; p < 0.001), and abnormal liver morphology defined as peripheral parenchymal atrophy and compensatory hypertrophy of central segments (32% vs. 7%; p < 0.001) were significantly more common in PSVD patients. Hypertrophy of segment I (70% vs. 84%; p = 0.019), atrophy of segment IV (24% vs. 47%; p = 0.001), and nodular liver surface (22% vs. 89%; p < 0.001) were more common in patients with cirrhosis. In patients with gadoxetic acid-enhanced MRI, we identified the distinct imaging feature of "periportal hyperintensity" in the hepatobiliary phase (HBP) in 42% of patients with PSVD (14/33) vs. 1% in cirrhosis (1/95) vs. 0% in non-cirrhotic controls (0/41); p < 0.001).

CONCLUSIONS

Diagnosis of PSVD must be considered in younger patients presenting with clinical features of portal hypertension, portal tract abnormalities, and FNH-like lesions on CT/MRI. 'Periportal hyperintensity' in the HBP of gadoxetic acid-enhanced MRI was identified as a specific radiological feature of PSVD.

KEY POINTS

• Cross-sectional imaging can provide essential information to identify patients with porto-sinusoidal vascular disorder (PSVD). • Intrahepatic portal tract abnormalities, FNH-like lesions, and abnormal liver morphology are common in PSVD patients. • Periportal hyperintensity on the hepatobiliary phase of gadoxetic acid-enhanced MRI seems to be specific for patients with PSVD.

Noncirrhotic portal hypertension due to peripheral T-cell lymphoma, not otherwise specified: A case report

BACKGROUND

Peripheral T-cell lymphoma (PTCL), an aggressive and rare disease that belongs to a heterogeneous group of mature T-cell lymphomas, develops rapidly and has a poor prognosis. Early detection and treatment are essential to improve patient cure and survival rates. Here, we report a rare case of PTCL with clinical presentation of noncirrhotic portal hypertension, which provides a basis for early vigilance of lymphomas in the future.

CASE SUMMARY

A 65-year-old Chinese woman was admitted to our hospital because of abdominal distension for 3 months and pitting oedema of both lower limbs for 2 months. Physical examinations and associated auxiliary examinations showed the presence of hepatosplenomegaly, and her hepatic venous pressure gradient was 10 mmHg. Immunohistochemical analysis of the liver biopsy confirmed the diagnosis of PTCL. The patient underwent combination therapy with dexamethasone, VP-16, and chidamide. Unfortunately, after 41 days of chemotherapy, the patient died of multiple organ failure.

CONCLUSION

PCTL accompanied by noncirrhotic portal hypertension is rarely reported. This case report discusses the diagnosis of a patient according to the literature.

Porto-sinusoidal vascular disease with portal hypertension versus liver cirrhosis: differences in imaging features on CT and hepatobiliary contrast-enhanced MRI

PURPOSE

To differentiate the computed tomography (CT) and magnetic resonance imaging (MRI) features of porto-sinusoidal vascular disease (PSVD) and liver cirrhosis (LC).

METHODS

In this retrospective case-control study of patients with PSVD matched in a 1:3 ratio with LC patients according to liver function, initial diagnosis and time to final diagnosis were analyzed. Imaging features on CT and the parenchymal enhancement on hepatobiliary phase of hepatobiliary agent-enhanced MRI (HBA-MRI) were compared using a generalized linear mixed model. Focal hepatic lesions in the PSVD group were analyzed.

RESULTS

In total, 43 PSVD patients and 129 LC patients were included. Among PSVD patients, 72.1% were initially misdiagnosed with LC. PSVD patients had a longer diagnostic delay than LC patients (32 months vs. 4 months; p < 0.001). Liver surface nodularity was less common in the PSVD group than in the LC group (16.3% vs. 89.2%, p < 0.001). Increased caudate-to-right lobe ratio, heterogeneous parenchymal enhancement, and portal vein abnormalities were more frequently noted in the PSVD group than in the LC group (all p < 0.001). The grade of portal hypertension was significantly higher in the PSVD group than in the LC group (p < 0.001), and they also had brighter parenchymal enhancement during the hepatobiliary phase of HBA-MRI (p < 0.001). In the PSVD group, 14% patients had at least one focal hepatic lesion, primarily a focal nodular hyperplasia (FNH)-like nodule.

CONCLUSIONS

Some imaging features on CT and HBA-MRI can distinguish PSVD from LC. Benign focal lesions, most commonly FNH-like nodules, can develop in PSVD.

Idiopathic Non-Cirrhotic Portal Hypertension and Porto-Sinusoidal Vascular Disease: Review of Current Data

Idiopathic non-cirrhotic portal hypertension (INCPH) is a clinicopathologic disease entity characterized by the presence of clinical signs and symptoms of portal hypertension (PH) in the absence of liver cirrhosis or known risk factors accountable for PH. Multiple hematologic, immune-related, infectious, hereditary and metabolic risk factors have been associated with this disorder. Still, the exact etiopathogenesis is largely unknown. The recently proposed porto-sinusoidal vascular disease (PSVD) scheme broadens the spectrum of the disease by also including patients without clinical PH who are found to have similar histopathologic findings on core liver biopsies. Three histomorphologic lesions have been identified as specific for PSVD to include obliterative portal venopathy, nodular regenerative hyperplasia and incomplete septal cirrhosis/fibrosis. However, these findings are often subtle, under-recognized and subjective with low interobserver agreement among pathologists. Additionally, the natural history of the subclinical forms of the disease remains unexplored. The clinical course is more favorable compared to cirrhosis patients, especially in the absence of clinical PH or liver dysfunction. There are no universally accepted guidelines in regard to diagnosis and treatment of INCPH/PSVD. Hence, this review emphasizes the need to raise awareness of this entity by highlighting its complex pathophysiology and clinicopathologic associations. Lastly, formulation of standardized diagnostic criteria with clinical validation is necessary to avoid misclassifying vascular diseases of the liver and to develop and implement targeted therapeutic strategies.

Variceal Bleed and Portal Hypertensive Gastropathy in a Noncirrhotic Patient with Isolated Splenomegaly

Portal hypertension caused by cirrhosis is the most common etiology of esophageal varices. However, abnormalities of the splenoportal axis in the absence of liver disease may also cause portal hypertension resulting in varices. We report a rare case of esophageal variceal bleed in a noncirrhotic patient with isolated splenomegaly secondary to chronic granulocyte colony stimulating factor (G-CSF) therapy. The patient is a 26-year-old male with Cohen syndrome who required long-term G-CSF treatment for chronic neutropenia. He presented with large volume hematemesis and pancytopenia in the setting of known splenomegaly with no evidence of cirrhosis. An urgent EGD revealed active variceal bleeding and portal hypertensive gastropathy. The patient was appropriately resuscitated and underwent a successful transjugular intrahepatic portosystemic shunt and CT-guided coil placement for the bleeding varices. We are the first to report variceal bleed as a complication of long-term G-CSF use, a life-threatening consequence that requires urgent intervention.

Diagnostic challenges in non-cirrhotic portal hypertension - porto sinusoidal vascular disease

Non-cirrhotic portal hypertension consists of a group of diseases characterized by signs and complications of portal hypertension, which differ from cirrhosis through histological alterations, hemodynamic characterization and, clinical outcome. Because of the similarities in clinical presentation and imaging signs, frequently these patients, and particularly those with porto-sinusoidal vascular disease (PSVD), are misdiagnosed as having liver cirrhosis and thus raising difficulties in their diagnosis. The most challenging differentiation to be considered is between PSVD and cirrhosis and, although not pathognomonic, liver biopsy is still the standard of diagnosis. Although they still require extended validation before being broadly used, new non-invasive methods for the diagnosis of porto-sinusoidal vascular disease, like transient elastography, contrast-enhanced ultrasound or metabolomic profiling, have shown promising results. Another issue is the differentiation between PSVD and chronic extrahepatic portal vein obstruction, especially now when it is known that 40% of patients suffering from PSVD develop portal vein thrombosis. In this particular case, once the portal vein thrombosis occurred, the diagnosis of PSVD is impossible according to the current guidelines. Moreover, so far, the differentiation between PSVD and sinusoidal obstruction syndrome has not been clear so far in particular circumstances. In this review we highlighted the diagnostic challenges regarding the PSVD, as well as the current techniques used in the evaluation of these patients.

Can we differentiate HIV-associated obliterative portopathy from liver cirrhosis using MRI?

AIM

To describe the magnetic resonance imaging (MRI) features of HIV-associated obliterative portopathy (HIV-OP) and determine the most indicative appearance of this condition on MRI by using a retrospective case-control study.

METHODS

MRI examinations of 24 patients with HIV-OP (16 men, 8 women; mean age = 48 ± 6.6 [SD] years; age range, 35-71 years) were analyzed by two blinded observers and compared with those obtained in 18 HIV-infected patients with hepatic cirrhosis (14 men, 4 women; mean age = 51 ± 3.4 [SD] years; age range, 35-60 years). Images were qualitatively and quantitatively analyzed with respect to imaging presentation. Comparisons were performed using uni- and multivariate analyses.

RESULTS

Regular liver contours had the highest accuracy for the diagnosis of HIV-OP (83%, 35 of 42; 95% confidence interval [CI], 69-93%) and was the most discriminating independent variable for the diagnosis of HIV-OP (odds ratio, 51; 95%CI, 4.96-1272%) (p < 0.0001). At multivariate analysis, the width of segment 4 in millimeters (OR = 1.23 [95%CI, 1.05-1.44%]; p = 0.011) and the presence of regular liver contours (OR = 7.69 [95%CI, 1.48-39.92%]; p = 0.015) were the variables independently associated with the diagnosis of HIV-OP.

CONCLUSIONS

Regular liver contours are the most discriminating independent variable for the diagnosis of HIV-OP but have limited accuracy. Familiarity with this finding may help differentiate HIV-OP from cirrhosis in HIV-infected patients.

KEY POINTS

• Regular liver contour is the most discriminating independent variable for the diagnosis of HIV-OP (odds ratio = 51) with 83% accuracy. • At multivariate analysis, the width of segment 4 in millimeters and the presence of regular liver contours are the variables independently associated with the diagnosis of HIV-OP. • MRI helps diagnose HIV-OP in the presence of several categorical findings, which are more frequently observed in HIV-OP patients than in HIV patients with cirrhosis.

Recanalization of Chronic Portal Vein Occlusion in Pediatric Liver Transplant Patients

PURPOSE

To evaluate technical and clinical success and report long-term outcomes of portal vein (PV) recanalization in pediatric orthotopic liver transplant (OLT) patients with chronic PV occlusion.

MATERIALS AND METHODS

This is a retrospective review of 15 OLT patients (5 males) with chronic PV occlusion who underwent PV recanalization (33 procedures) between October 2011 and February 2018. Median age was 4.5 years (range, 1-16 years); median weight was 16.6 kg (range, 11.5-57.3 kg). Median time interval from OLT to first intervention was 3.25 years (range, 0.6-15.7 years). Clinical presentations included hypersplenism (n = 12), gastrointestinal bleeding (n = 9), and ascites (n = 3). One patient had incidental diagnosis of PV occlusion. Primary, primary-assisted, and secondary patency at 3, 6, 12, and 24 months were evaluated.

RESULTS

Technically successful PV recanalization and reduction of PV pressure gradient to ≤ 5 mm Hg was performed in 13/15 patients (87%). Ten of 15 (67%) patients had successful recanalization with the first attempt. Clinical success, defined as improvement in signs and symptoms of portal hypertension, was achieved in 12/13 (92%) patients. Five of 33 (15%) major complications (Society of Interventional Radiology class C), including perisplenic hematoma (n = 2), hemoperitoneum (n = 2), and hepatic artery pseudo aneurysm (n = 1), were managed with pain medication and blood product replacement. Median follow-up was 22 months (range, 1-77 months). Median primary patency was 5 months. Primary patency at 3, 6, 12, and 24 months was 53.8%, 46.2%, 38.5%, and 30.8%, respectively. Primary-assisted patency was 84.6%, 76.9%, 53.8%, and 46.2%, respectively. Secondary patency was 92.3%, 84.6%, 53.8%, and 46.2%, respectively.

CONCLUSIONS

PV recanalization is a safe and effective minimally invasive option in the management of chronic PV occlusion after pediatric OLT.