Trends in liver transplantation for primary sclerosing cholangitis

BACKGROUND

Primary sclerosing cholangitis is a cholestatic disease with a low prevalence in Italy. Indications for liver transplantation and the time of listing are not stated.

AIM

We performed a national survey to investigate the listing criteria, comorbidities, and outcomes.

METHODS

In April 2022, we surveyed liver transplantation in primary sclerosing cholangitis nationwide for the last 15 years.

RESULTS

From 2007 to 2021, 445 patients were included on waiting lists, and 411 had undergone liver transplants. The median age at transplantation was 46 years (males 63.9%); 262 patients (59%) presented an inflammatory bowel disease. Transplants increased over the years, from 1.8 % in 2007 to 3.0 % in 2021. Cholangitis (51%) and hepatic decompensation (45%) were the main indications for listing. The disease recurred in 81 patients (20%). Patient survival after the first transplant was 94 %, 86% and 84% at one, five, and ten years. Twenty-four died in the first year (50% surgical complications, 25% infections); 33 between one to five years (36% recurrence, 21% cholangiocarcinoma recurrence) and nine after five years (56% de novo cancer, 44% recurrence).

CONCLUSIONS

Primary sclerosing cholangitis has been an increasing indication for transplantation in Italy. Cholangitis and decompensation were the main indications for listing. Recurrence and cancer were the leading causes of death.

The Italian data on SARS-CoV-2 infection in transplanted patients support an organ specific immune response in liver recipients

Introduction

The study of immune response to SARSCoV-2 infection in different solid organ transplant settings represents an opportunity for clarifying the interplay between SARS-CoV-2 and the immune system. In our nationwide registry study from Italy, we specifically evaluated, during the first wave pandemic, i.e., in non-vaccinated patients, COVID-19 prevalence of infection, mortality, and lethality in liver transplant recipients (LTRs), using non-liver solid transplant recipients (NL-SOTRs) and the Italian general population (GP) as comparators.

Methods

Case collection started from February 21 to June 22, 2020, using the data from the National Institute of Health and National Transplant Center, whereas the data analysis was performed on September 30, 2020.To compare the sex- and age-adjusted distribution of infection, mortality, and lethality in LTRs, NL-SOTRs, and Italian GP we applied an indirect standardization method to determine the standardized rate.

Results

Among the 43,983 Italian SOTRs with a functioning graft, LTRs accounted for 14,168 patients, of whom 89 were SARS-CoV-2 infected. In the 29,815 NL-SOTRs, 361 cases of SARS-CoV-2 infection were observed. The geographical distribution of the disease was highly variable across the different Italian regions. The standardized rate of infection, mortality, and lethality rates in LTRs resulted lower compared to NL-SOTRs [1.02 (95%CI 0.81-1.23) vs. 2.01 (95%CI 1.8-2.2); 1.0 (95%CI 0.5-1.5) vs. 4.5 (95%CI 3.6-5.3); 1.6 (95%CI 0.7-2.4) vs. 2.8 (95%CI 2.2-3.3), respectively] and comparable to the Italian GP.

Discussion

According to the most recent studies on SOTRs and SARS-CoV-2 infection, our data strongly suggest that, in contrast to what was observed in NL-SOTRs receiving a similar immunosuppressive therapy, LTRs have the same risk of SARS-CoV-2 infection, mortality, and lethality observed in the general population. These results suggest an immune response to SARS-CoV-2 infection in LTRS that is different from NL-SOTRs, probably related to the ability of the grafted liver to induce immunotolerance.

Safety and efficacy of venous thromboembolism prophylaxis in patients with cirrhosis: A systematic review and meta-analysis

BACKGROUND & AIMS

Patients with cirrhosis are considered in a haemostatic balance, though weaker than in normal subjects. In these patients, however, the use of pharmacological prophylaxis for venous thromboembolism (VTE) remains controversial. Therefore, in this study, we aimed to assess the safety and efficacy of VTE prophylaxis in patients with cirrhosis.

METHODS

We conducted a systematic review of studies reporting the occurrence of bleeding and VTE events in patients with cirrhosis, and controls, undergoing VTE prophylaxis. Meta-regression analysis was conducted to further explore the determinants of heterogeneity in the study of the occurrence of either bleeding or VTE events.

RESULTS

In a total of 10 studies, including 5712 patients, of which 2330 undergoing VTE prophylaxis, bleeding (n = 5513) and VTE events occurred in 8.2% and 2.8% patients respectively. A total of 2963 and 3162 patients were included from low-risk of bias studies in bleeding and VTE analysis respectively: while administration of VTE prophylaxis did not seem to reduce VTE (OR = 1.07, CI 0.39-2.96, p = .89), importantly prophylaxis was not associated with increased bleeding risk (OR = 0.56, CI 0.20-1.59, p = .27). Meta-regression analysis showed that no parameter significantly influenced the heterogeneity of data regarding bleeding or VTE events.

CONCLUSIONS

In patients with cirrhosis, current evidence is insufficient to advise for or against the use of VTE prophylaxis, mainly due to lack of quality and homogeneity of available data. However, its use does not appear to be associated with a significant bleeding risk. Adequately designed studies are required to provide a measure of its overall utility.

Immune checkpoint inhibitors in malignancies after liver transplantation: A systematic review and pooled analysis

BACKGROUND AND AIMS

Treatment of de novo malignancies and recurrent hepatocellular carcinoma with immune checkpoint inhibitors (ICI) in liver transplant recipients (LT) is an attractive strategy that is infrequently pursued because of the lack of strong evidence regarding their safety and efficacy. In this systematic review with pooled analysis, we aimed to assess safety and efficacy of ICI therapy following LT.

METHODS

We performed a systematic search of case reports and series published until January 2022. We included 31 publications reporting a total of 52 patients treated with ICIs after LT and assessed in a pooled analysis the risk of graft rejection and the outcome of ICI therapy.

RESULTS

Acute graft rejection occurred in 15 patients (28.8%) and 7 patients (13.4% of the total cohort) died because of graft loss. Rejection was associated with shorter overall survival (OS) (17.2 months, confidence interval [CI] 12.1-22.2 vs. 3.5 months, CI 1.6-5.4, p < 0.001). Disease control rate was 44.2% (n = 23), and in these patients, OS was longer than in non-responders (26.4 months, CI 20.8-32.0 vs. 3.4 months, CI 2.1-4.7, p < 0.001).

CONCLUSIONS

Observational, off-label experience suggests that treatment with ICI for advanced malignancies in LT recipients might not be discarded a priori. This notwithstanding, ICI treatment in these patients is associated with a substantial risk of graft rejection and mortality. Prospective studies are needed to provide adequate safety and efficacy figures of ICI treatment in this fragile population.

Safe pregnancy after liver transplantation: Evidence from a multicenter Italian collaborative study

BACKGROUND

Women who have undergone liver transplantation (LT) enjoy better health, and possibility of childbearing. However, maternal and graft risks, optimal immunosuppression, and fetal outcome is still to clarify.

AIM

Aim of the study was to assess outcomes of pregnancy after LT at national level.

METHODS

In 2019, under the auspices of the Permanent Transplant Committee of the Italian Association for the Study of the Liver, a multicenter survey including 14 Italian LT-centers was conducted aiming at evaluating the outcomes of recipients and newborns, and graft injury/function parameters during pregnancy in LT-recipients.

RESULTS

Sixty-two pregnancies occurred in 60 LT-recipients between 1990 and 2018. Median age at the time of pregnancy was 31-years and median time from transplantation to conception was 8-years. During pregnancy, 4 recipients experienced maternal complications with hospital admission. Live-birth-rate was 100%. Prematurity occurred in 25/62 newborns, and 8/62 newborns had low-birth-weight. Cyclosporine was used in 16 and Tacrolimus in 37 pregnancies, with no different maternal or newborn outcomes. Low-birth-weight was correlated to high values of AST, ALT and GGT.

CONCLUSION

Pregnancy after LT has good outcome; however, maternal complications and prematurity may occur. Compliance with the immunosuppression is fundamental to ensure the stability of graft function and prevent graft-deterioration.

Coracoid tunnels in open and arthroscopic treatment of acromioclavicular dislocation: an experimental cadaveric study

PURPOSE

Treatment of acromioclavicular joint (ACJ) dislocation is not encoded uniquely. Type I and II injuries are usually treated conservatively, while types IV, V and VI surgically. Controversy still exists over the treatment of type III injuries. In the operative approach, there is no agreement on the best surgical technique. Our purpose is to compare the mini-open and arthroscopic approach focusing on the evaluation of the anatomical precision of the coracoid drilling.

METHODS

This is a controlled laboratory study. Ten fresh-frozen cadaveric shoulders were randomly assigned to the two techniques in order to compare them. We performed essential surgical gestures to drill the tunnel using MINAR® System (mini-open) and Dog-Bone® (ARTHREX, arthroscopic). The anatomical specimens were then subjected to CT-scan investigation. We statistically evaluated the precision of these two techniques analyzing DICOM files using two parameters. Parameter 1 evaluates the tunnel entry area on the superior side of the coracoid. Parameter 2 describes the orientation of the tunnel.

RESULTS

There are no statistically significant differences (95% confidence level) between arthroscopic and mini-open approach about the precision in the location of the coracoid hole, regarding the entry area (p = 1.00) and the orientation (p = 0.196).

CONCLUSION

The evidences collected enable the orthopedic surgeon to choose equally between the two techniques in the treatment of AC joint dislocation toward precision.

Hepatic Elastometry and Glissonian Line in the Assessment of Liver Fibrosis

The aim of this study was to identify a method for staging hepatic fibrosis using a non-invasive, rapid and inexpensive technique based on ultrasound morphologic hepatic features. A total of 215 patients with different liver diseases underwent B-mode (2-D brightness mode) ultrasonography, vibration-controlled transient elastography, 2-D shear wave elastography and measurement of the controlled attenuation parameter with transient elastography. B-Mode images of the anterior margin of the left lobe were obtained and processed with automatic Genoa Line Quantification (GLQ) software based on a neural network for staging liver fibrosis. The accuracy of GLQ was 90.6% during model training and 78.9% in 38 different patients with concordant elastometric measures. Receiver operating characteristic curve analysis of GLQ performance using vibration-controlled transient elastography as a reference yielded areas under the curves of 0.851 for F ≥ F1, 0.793 for F ≥ F2, 0.784 for F ≥ F3 and 0.789 for F ≥ F4. GLQ has the potential to be a rapid, easy-to-perform and tolerable method in the staging of liver fibrosis.

Oxytocin receptor mRNA expression in dorsolateral prefrontal cortex in major psychiatric disorders: A human post-mortem study

There is growing interest in oxytocin as a putative treatment for various psychiatric disorders including major depressive disorder, bipolar disorder and schizophrenia/schizoaffective disorder. However, potential alterations in the endogenous brain oxytocin system in these disorders are poorly characterized. Brain expression of oxytocin and its receptor genes in patients with these psychiatric disorders has not been well studied outside the hypothalamus. We measured expression of mRNA for oxytocin and its receptor in the dorsolateral prefrontal cortex of postmortem brains using quantitative polymerase chain reaction in a total of 581 individuals. These individuals either were diagnosed with major depressive disorder (n = 135), bipolar disorder (n = 57), schizophrenia/schizoaffective disorder (n = 169), or were control subjects, defined as individuals with no lifetime history of any of these disorders (n = 220). Diagnoses of major depressive disorder and bipolar disorder were associated with significantly increased oxytocin receptor mRNA levels in the dorsolateral prefrontal cortex. This finding is discussed in light of the extant literature on the dysregulation of oxytocin signaling in individuals with major psychiatric disorders.

Cost per care of the first year of direct antiviral agents in the Liguria Region: a multicenter analysis

Aims

Despite the remarkable efficacy shown in clinical practice, concerns have been raised about the costs associated with direct antiviral agent (DAA) therapy. This article presents the real-life costs for DAA treatment sustained by the Italian National Health Service in the Liguria Region (Northern Italy).

Methods

A retrospective analysis of the cost per care sustained for DAA treatment, relating to the period from January 1 to December 31, 2015 in five centers in Liguria was performed. All patients undergoing DAA-based treatments for hepatitis C virus (HCV) infection were enrolled. On-treatment costs included: HCV treatment, laboratory test, outpatient services, attended visits, drugs used for the management of adverse events (erythropoietin, albumin or red blood cell packs) and inpatient service admissions.

Results

In total, 327 patients were enrolled. No difference in terms of sustained virologic response (SVR) rate among different treatments was reported. The majority (85.0%) of patients did not report any side effects and only 15 (4.6%) required hospital admission. Forty-two patients (12.8%) required high-cost drugs for the management of adverse events. The overall cost sustained was €14,744,433. DAA±ribavirin (RBV) accounted for the wide majority of this cost (98.9%; €14,585,123). Genotype (GT) 1, the most commonly treated GT, was associated with an average cost of €43,445 per patient. Detailed analysis of the costs for GT 1 showed the treatment based on ritonavir boosted paritaprevir/ombitasvir + dasabuvir±RBV with an average cost of €24,978 (RBV+) and €25,448 (RBV−) per patient was the most cost-effective. The average cost per SVR was €48,184. Once again, the ritonavir boosted paritaprevir/ombitasvir + dasabuvir regimen was associated with the lowest cost/SVR (€25,448/SVR [GT 1b] and similar results for other GTs).

Conclusion

Antiviral regimen is the major contributor to costs in the treatment of HCV infection. Appropriate regimen selection could result in a major cost saving, which can be reinvested to allow more patients to be treated.

Behavior of soluble HLA-A, -B, -C and HLA-G molecules in patients with chronic hepatitis C virus infection undergoing pegylated interferon-α and ribavirin treatment: potential role as markers of response to antiviral therapy

The serum levels of soluble HLA class I antigens (sHLA-A, -B, -C and sHLA-G) were determined in 40 HCV genotype 1-infected patients before (T ₀), after 3, 6, and 12 months (T ₃, T ₆, and T ₁₂) of pegylated-IFN-α plus ribavirin therapy and 6 months (T ₁₈) after the end of treatment. Twenty patients were sustained virological responders (SVR), and 20 were non-responders (NR). sHLA-A, -B, -C levels at T ₀ were significantly higher in both SVR (mean 10.48 μg/ml) and NR (mean 11.87 μg/ml) patients as compared to healthy controls (mean 0.34 μg/ml, p < 0.0001) and HIV-infected subjects (mean 1.22 μg/ml, p < 0.0001). sHLA-G levels at T ₀ were significantly higher in SVR (mean 24.78 ng/ml) and NR (mean 24.93 ng/ml) patients as compared to healthy controls (mean 10.34 ng/ml, p = 0.015 and p = 0.014, respectively) but were lower as compared to HIV-infected subjects (mean 48.00 ng/ml, p < 0.0001). The levels of sHLA-A, -B, -C and sHLA-G significantly decreased in SVR from T ₀ to T ₁₈ (mean 1.64 and 1.43 ng/ml, respectively, p < 0.0001) and correlated with HCV-RNA, AST, ALT, γGT, and ALP levels. The determination of soluble HLA class I levels could be proposed as a surrogate marker to discriminate SVR and NR HCV-infected patients during PEG-IFN-α plus ribavirin therapy.

The Treatment of Hepatorenal Syndrome

Hepatorenal syndrome (HRS) is a severe complication that often occurs in patients with cirrhosis and ascites. HRS is a functional renal failure that develops mainly as a consequence of a severe cardiovascular dysfunction which is characterized by an extreme splanchnic arterial vasodilation and a reduction of cardiac output. HRS may develop in two clinical types: as an acute and rapidly progressive renal failure (AKI-HRS) or as chronic and not progressive renal failure (CKD-HRS). Several small studies and some randomized control studies have been published on the use of terlipressin plus albumin in the treatment of HRS, mainly on AKI-HRS. Terlipressin plus albumin was shown to improve renal function in almost 35-45% of patients with AKI-HRS, as well as to improve short-term survival in these patients. Terlipressin was most commonly used by intravenous boluses moving from an initial dose of 0.5-1 mg every 4 h to 3 mg every 4 h in the case of a nonresponse. In other studies, terlipressin was also given by continuous intravenous infusion. Thus, the best way to administer terlipressin in the treatment of HRS has not yet been defined. α-Adrenergic drugs, such as intravenous norepinephrine or oral midodrine plus subcutaneous octreotide, administered with albumin have also been used in the treatment of AKI-HRS, with promising results. However, we need further studies in order to define whether they can represent a real therapeutic alternative. In conclusion, available data are sufficient to state that the use of terlipressin plus albumin has really changed the management of HRS. Nevertheless, some crucial unsolved issues still exist, in particular: (a) how to predict nonresponse to treatment, (b) how to manage nonresponse to treatment and (c) how to consider the response in those patients who are candidates for liver transplant in the priority allocation process.

[Therapeutic decisions and treatment with sorafenib in hepatocellular carcinoma: final analysis of GIDEON study in Italy]

INTRODUCTION

Sorafenib, an oral multikinase inhibitor, is the only targeted agent approved for the treatment of patients with hepatocellular carcinoma (HCC) after demonstration to increase overall survival compared to placebo in two randomized phase III study. GIDEON (Global Investigation of therapeutic DEcisions in HCC and Of its treatment with sorafeNib) is the largest, global, non-interventional, prospective study of patients with uHCC (n>3200) treated with sorafenib in real-life clinical practice conditions. Here we report the final analysis of safety and efficacy in the Italian cohort of patients.

METHODS

Patients with unresectable HCC who are candidates for systemic therapy, and for whom a decision has been made to treat with sorafenib, are eligible for inclusion. Patients demographics disease characteristics and treatment history were recorded at baseline visit. Sorafenib dose, concomitant medications, performance status, liver function, adverse events and efficacy (survival and response rate) were collected throughout the study.

RESULTS

In the Italian cohort of the GIDEON study 278 patients were included in 36 centers. The global rate of adverse events was 81%. Drug-related events accounted for 67%, mostly of grade 1 and 2, and only 8% were classified as serious. The most common were diarrhea (24%), fatigue (23%), dermatological (14%), rash/exfoliation (10%), hypertension (9%), hemorrage/bleeding of gastrointestinal tract (6%). Overall survival was 14.4 months and time to progression 6.2 months. Objective responses were observed in 14 patients (5%) with 3 complete responses (1%). Stable diseases of at least 6 weeks were observed in 113 patients (41%) with a 30% of disease control rate.

DISCUSSION

The safety profile of sorafenib in terms of rate and type of adverse events is similar to that emerged in the global international GIDEON study as well as in the pivotal registration studies.

Undetectable HCV-RNA at treatment-week 8 results in high-sustained virological response in HCV G1 treatment-experienced patients with advanced liver disease: the International Italian/Spanish Boceprevir/Peginterferon/Ribavirin Name Patients Program

In many countries, first-generation protease inhibitors (PIs)/peginterferon/ribavirin (P/R) still represent the only treatment option for HCV-infected patients. Subjects with advanced disease and previous failure to P/R urgently need therapy, but they are under-represented in clinical trials. All treatment-experienced F3/4 Metavir patients who received boceprevir (BOC)+P/R in the Italian-Spanish Name Patient Program have been included in this study. Multivariate logistic regression analysis (MLR) was used to identify baseline and on-treatment predictors of SVR and adverse events (AEs). Four hundred and sixteen patients, mean age 57.7 (range 25-78 years), 70% males, 69.5% (289/416) F4, 14% (41/289) Child-Pugh class A6, 24% (70/289) with varices and 42% (173/416) prior null responders to P/R, were analysed. Overall, SVR rate (all 381 patients who received one dose of BOC) was 49%, (58% in F3, 45% in F4, 61% in relapsers, 51% in partial, 38% in null responders, and 72% in subjects with undetectable HCV-RNA at treatment-week (TW)8. Among patients with TW8 HCV-RNA ≥ 1000 IU/L, SVR was 8% (negative predictive value = 92%). Death occurred in 3 (0.8%) patients, while decompensation and infections were observed in 2.9% and 11%, respectively. At MLR, SVR predictors were TW4 HCV-RNA ≥ 1log10 -decline from baseline, undetectable TW8 HCV-RNA, prior relapse, albumin levels ≥3.5 g/dL and platelet counts ≥100 000/μL. Metavir F4, Child-Pugh A6, albumin, platelets, age and female gender were associated with serious and haematological AEs. Among treatment-experienced patients with advanced liver disease eligible for IFN-based therapy, TW8 HCV-RNA characterised the subset with either high or poor likelihood of achieving SVR. Using TW8 HCV-RNA as a futility rule, BOC/P/R appears to have a favourable benefit-risk profile.

HOMA, BMI, and Serum Leptin Levels Variations during Antiviral Treatment Suggest Virus-Related Insulin Resistance in Noncirrhotic, Nonobese, and Nondiabetic Chronic Hepatitis C Genotype 1 Patients

Objective. To investigate the relationship between insulin resistance and viral load decay in nondiabetic and noncirrhotic genotype 1 chronic HCV patients during peginterferon and ribavirin treatment and the possible influence of BMI and leptin as metabolic confounders. Methods. 75 consecutive noncirrhotic, nonobese, and nondiabetic patients with genotype 1 chronic hepatitis C treated with peginterferon alpha 2a plus ribavirin were evaluated. HOMA-IR, serum leptin, and BMI were measured in all patients at baseline and at weeks 12 and 48, whereas viral load was measured at the same time points and then 24 weeks after the end of treatment. Results. HOMA-IR was significantly associated with both BMI and leptin at baseline. During peginterferon plus ribavirin treatment, there was a significant reduction of HOMA-IR at weeks 12 and 48 from baseline (P = 0.033 and 0.048, resp.) in patients who achieved an early viral load decay (EVR), a trend not observed in patients who not achieved EVR. No variations during treatment were observed regarding BMI and leptin irrespective of EVR. Conclusion. The early reduction of HOMA-IR but not of BMI and leptin during antiviral treatment in noncirrhotic, chronic hepatitis C genotype 1 patients who achieved EVR suggests a viral genesis of insulin resistance in patients with nonmetabolic phenotype.

Inherent transcriptional signatures of NK cells are associated with response to IFNα + rivabirin therapy in patients with Hepatitis C Virus

BACKGROUND

Differences in the expression of Natural Killer cell receptors have been reported to reflect divergent clinical courses in patients with chronic infections or tumors. However, extensive molecular characterization at the transcriptional level to support this view is lacking. The aim of this work was to characterize baseline differences in purified NK cell transcriptional activity stratified by response to treatment with PEG-IFNα/RBV in patients chronically infected with HCV.

METHODS

To this end we here studied by flow cytometer and gene expression profile, phenotypic and transcriptional characteristics of purified NK cells in patients chronically infected with HCV genotype-1 virus who were subsequently treated with PEG-IFNα/RBV. Results were further correlated with divergent clinical response obtained after treatment.

RESULTS

The pre-treatment transcriptional patterns of purified NK cells from patients subsequently undergoing a sustained virologic response (SVR) clearly segregated from those of non-responder (NR) patients. A set of 476 transcripts, including molecules involved in RNA processing, ubiquitination pathways as well as HLA class II signalling were differently expressed among divergent patients. In addition, treatment outcome was associated with differences in surface expression of NKp30 and NKG2D. A complex relationship was observed that suggested for extensive post-transcriptional editing. Only a small number of the NK cell transcripts identified were correlated with chronic HCV infection/replication indicating that inherent transcriptional activity prevails over environment effects such as viral infection.

CONCLUSIONS

Collectively, inherent/genetic modulation of NK cell transcription is involved in setting the path to divergent treatment outcomes and could become useful to therapeutic advantage.

Hepatocellular carcinoma in patients without cirrhosis in Italy

BACKGROUND

In the Western world, hepatocellular carcinoma seldom develops in patients without cirrhosis, and reports describing the characteristics of non-cirrhotic patients with hepatocellular carcinoma are rather infrequent.

METHODS

We evaluated the main clinical characteristics, treatment options, and survival of patients with hepatocellular carcinoma developed in non-cirrhotic liver among the 3027 consecutive cases of hepatocellular carcinoma accrued in the Italian Liver Cancer database during the last 20 years.

RESULTS

We identified 52 patients with hepatocellular carcinoma in non-cirrhotic livers (1.7% of all hepatocellular carcinomas), 42 with (80.8%) and 10 without (19.2%) chronic liver disease. In patients without chronic liver disease, median tumour diameter was greater compared to patients with chronic liver disease (7.8 versus 4.0 cm, P=0.046). Curative treatment was feasible in 20 patients (38.5%). Median overall survival was 26 months and 5-year survival rate was 23.7%. Detection of hepatocellular carcinoma outside surveillance (P=0.036), advanced hepatocellular carcinoma stage (P<0.0001), and non-curative treatment (P=0.007) were associated with worse prognosis, but tumour stage was the only independent predictor of survival.

CONCLUSIONS

In Italy, less than 2% of hepatocellular carcinomas develop in a non-cirrhotic liver, and almost never in a normal liver. These patients frequently present with advanced tumours, have low eligibility rates for curative treatment, and have a dismal prognosis despite their preserved liver function.

Bone marrow-derived cell mobilization by G-CSF to enhance osseointegration of bone substitute in high tibial osteotomy

PURPOSE

To evaluate granulocyte colony-stimulating factor (G-CSF) efficacy in accelerating bone regeneration following opening-wedge high tibial valgus osteotomy for genu varum.

METHODS

A phase II trial was conducted for evaluating the preoperative administration of G-CSF given at 10 μg/kg/day for 3 consecutive days with an additional half-dose 4 h before the opening-wedge high tibial valgus osteotomy. Overall, 12 patients (Group A) received G-CSF treatment, and the subsequent 12 patients (Group B) underwent surgery without G-CSF. The osteotomy gap was filled by a bone graft substitute. Bone marrow cell (BMC) mobilization was monitored by CD34+ve cell and clonogenic progenitor cell analysis. All patients underwent a clinical (Lysholm Knee Scale and SF-36) and radiographic evaluation preoperatively, as well as at given intervals postsurgery.

RESULTS

All patients completed the treatment program without major side effects; G-CSF was well tolerated. BMC mobilization occurred in all Group A patients, with median peak values of circulating CD34+ve cells of 110/μL (range 29-256). Circulating clonogenic progenitors paralleled CD34+ve cell levels. A significant improvement in Lysholm Knee Scale was recorded at follow-up in Group A compared to Group B. At the radiographic evaluation, there was a significant increase in osseointegration at the bone-graft junction in Group A at 1, 2, 3 and 6 months postsurgery compared to Group B. The computerized tomography scan of the grafted area at 2 months postsurgery showed no significant difference in the quality of the newly formed bone between the two Groups.

CONCLUSIONS

Although the limited number of patients does not allow firm conclusions, the study suggests that G-CSF can be safely administered preoperatively in subjects undergoing opening-wedge high tibial valgus osteotomy; in addition, the clinical, radiographic and CT monitoring indicate that G-CSF and/or mobilized BMCs may hasten bone graft substitute osseointegration.

LEVEL OF EVIDENCE

I.

Alpha-fetoprotein has no prognostic role in small hepatocellular carcinoma identified during surveillance in compensated cirrhosis

Alpha-fetoprotein is a tumor marker that has been used for surveillance and diagnosis of hepatocellular carcinoma (HCC) in patients with cirrhosis. The prognostic capability of this marker in patients with HCC has not been clearly defined. In this study our aim was to evaluate the prognostic usefulness of serum alpha-fetoprotein in patients with well-compensated cirrhosis, optimal performance status, and small HCC identified during periodic surveillance ultrasound who were treated with curative intent. Among the 3,027 patients included in the Italian Liver Cancer study group database, we selected 205 Child-Pugh class A and Eastern Cooperative Group Performance Status 0 patients with cirrhosis with a single HCC ≤ 3 cm of diameter diagnosed during surveillance who were treated with curative intent (hepatic resection, liver transplantation, percutaneous ethanol injection, radiofrequency thermal ablation). Patients were subdivided according to alpha-fetoprotein serum levels (i.e., normal ≤ 20 ng/mL; mildly elevated 21-200 ng/mL; markedly elevated >200 ng/mL). Patient survival, as assessed by the Kaplan-Meier method, was not significantly different among the three alpha-fetoprotein classes (P = 0.493). The same result was obtained in the subgroup of patients with a single HCC ≤ 2 cm (P = 0.714). An alpha-fetoprotein serum level of 100 ng/mL identified by receiver operating characteristic curve had inadequate accuracy (area under the curve = 0.536, 95% confidence interval = 0.465-0.606) to discriminate between survivors and deceased patients.

CONCLUSION

Alpha-fetoprotein serum levels have no prognostic meaning in well-compensated cirrhosis patients with single, small HCC treated with curative intent.

Peripheral blood cytopaenia limiting initiation of treatment in chronic hepatitis C patients otherwise eligible for antiviral therapy

BACKGROUND

In patients with chronic hepatitis C virus (HCV) infection, the presence of peripheral blood cytopaenia may represent an obstacle to pegylated interferon and ribavirin treatment.

AIMS

To evaluate the prevalence of anaemia, neutropaenia and thrombocytopaenia potentially limiting initiation of pegylated interferon and ribavirin treatment in patients with chronic HCV infection who were otherwise eligible for antiviral therapy.

METHODS

We studied 3059 consecutive anti-HCV and HCV-RNA positive patients referred to our centre to be evaluated for antiviral therapy from June 2002 to May 2011. The European Association for the Study of Liver HCV guidelines were applied to assess eligibility for antiviral therapy.

RESULTS

In the study cohort, 1,521 patients (49.7%) were not eligible for treatment because of reasons different from haematological abnormalities. In the remaining 1,538 patients the overall prevalence of any peripheral blood cytopaenia potentially preventing patients from being treated with antiviral therapy was 15.1%. In particular, anaemia (haemoglobin level < 12 g/dL for women, <13 g/dL for men) was a relative contraindication to treatment in 8.9% (137/1,538) of the patients, while thrombocytopaenia (platelet count cut-off, 90 × 10(9) /L) and neutropaenia (absolute neutrophil count < 1.5 × 10(9) /L) limited treatment in 6.5% (100/1358) and 3.2% (48/1358) of patients respectively. These haematological abnormalities were more prevalent in patients with older age (P < 0.004) and cirrhosis (P < 0.001).

CONCLUSIONS

The presence of peripheral blood cytopaenia may potentially limit initiation of antiviral therapy in one in every seven patients with chronic HCV infection who are otherwise eligible for treatment.

Use of the platelet count/spleen diameter ratio for the noninvasive diagnosis of esophageal varices in patients with schistosomiasis

BACKGROUND/AIM

In patients with liver cirrhosis, the platelet count/spleen diameter ratio has been validated as a parameter for the noninvasive diagnosis of esophageal varices. Schistosoma infection is a frequent cause of portal hypertension in Middle Eastern countries, and is associated with the development of esophageal varices. In this study we aimed to evaluate the platelet count/spleen diameter ratio as a noninvasive tool for the prediction of the presence of esophageal varices in patients with schistosoma-related chronic liver disease.

PATIENTS AND METHODS

Forty-three patients with hepatosplenic schistosomiasis underwent upper digestive endoscopy to check for the presence of esophageal varices. Furthermore, all patients underwent abdominal ultrasonography, and maximum spleen diameter (in mm) was measured. The platelet count/spleen diameter ratio was calculated in all patients.

RESULTS

Esophageal varices were found in 31 patients (72%). Age and gender were not significantly different between patients with and without varices. In patients with varices, median platelet count (82,000/μL versus 172,000/μL, P < 0.0001) and platelet count/spleen diameter ratio (571 versus 1651, P < 0.0001) were significantly lower, while spleen diameter (147 mm versus 109 mm, P = 0.0006) was significantly larger. In multivariate analysis, the platelet count/spleen diameter ratio was the only parameter independently associated with the presence of varices (P < 0.0001).

CONCLUSIONS

In this study we have validated the use of the platelet count/spleen diameter ratio for the noninvasive diagnosis of esophageal varices in patients with portal hypertension caused by schistosoma infection. In these patients, the platelet count/spleen diameter ratio might be used to allow better rationalization of medical resources and use of endoscopy.

Clinical trial: the combination of rifaximin with partially hydrolysed guar gum is more effective than rifaximin alone in eradicating small intestinal bacterial overgrowth

BACKGROUND

Abnormal intestinal clearance is involved in the pathogenesis of small intestinal bacterial overgrowth (SIBO). It is known that partially hydrolysed guar gum affects intestinal motility. Eradication therapy of SIBO is based on antibiotic treatment: no data are available on the role of fibre supplementation in eradicating SIBO.

AIM

To assess whether the combination of partially hydrolysed guar gum and rifaximin is more effective than rifaximin alone in the treatment of SIBO.

METHODS

A 50 g-glucose breath test was given to 500 consecutive patients. Patients with a positive glucose breath test and predisposing conditions to SIBO entered into the study, and were randomized to receive rifaximin 1200 mg/day or rifaximin 1200 mg/day plus partially hydrolysed guar gum 5 g/day for 10 days. Patients completed a symptom questionnaire and glucose breath test both in basal condition and 1 month after withdrawal of therapy.

RESULTS

Seventy-seven patients had SIBO. Eradication rate of SIBO was 62.1% in the rifaximin group (both on per-protocol and intention-to-treat analyses), and 87.1% (per-protocol, P=0.017) and 85.0% (intention-to-treat, P=0.036) in the rifaximin-plus-partially hydrolysed guar gum group. Clinical improvement was observed in 86.9% and 91.1% of eradicated cases in rifaximin and rifaximin-plus-partially hydrolysed guar gum groups respectively (P=0.677).

CONCLUSION

The combination of rifaximin with partially hydrolysed guar gum seems to be more useful in eradicating SIBO compared with rifaximin alone.

Successful antiviral therapy determines a significant decrease in squamous cell carcinoma antigen-associated (SCCA) variants' serum levels in anti-HCV positive cirrhotic patients

Aberrant squamous cell carcinoma antigen (SCCA) expression is an early event in hepatocarcinogenesis, and increasing serum levels of SCCA variants IgM immune complexes (SCCA-IgM IC) have been found in cirrhotic patients developing hepatocellular carcinoma (HCC). We longitudinally evaluated a cohort of cirrhotic patients with hepatitis C virus infection (HCV) who underwent pegylated interferon (PEG-IFN) and ribavirin treatment. SCCA-IgM IC levels were assessed in the sera of 33 cirrhotic patients with HCV (21 males, median age 57 years) before, at the end and at 6-month and 1-year follow-up after treatment with PEG-IFN and ribavirin. SCCA-IgM IC serum levels (arbitrary units/mL, AU/mL) were evaluated according to treatment outcome: sustained virological response (SVR) vs nonresponse (NR). Overall, 15 patients obtained a SVR to antiviral therapy (45%). There was no significant difference in baseline SCCA-IgM IC serum levels between SVR and NR patients. When compared to baseline (451.2 AU/mL), SVR patients showed a significant decrease in median SCCA-IgM IC serum levels at the end of treatment (186.8 AU/mL, P = 0.013) and at both 6-month (96.8 AU/mL, P < 0.001) and 1-year follow-up (52.4 AU/mL, P < 0.001), while no significant modification was observed in NR patients. In patients with HCV-related liver cirrhosis, successful antiviral therapy is associated with a dramatic and significant decrease in SCCA-IC serum levels. Because of the pathophysiological correlation between SCCA and liver carcinogenesis, it is hypothesized that in patients with liver cirrhosis, SVR may be accompanied by a decreased proliferative stimulation.

The Premorbid Adjustment Scale as a measure of developmental compromise in patients with schizophrenia and their healthy siblings

Schizophrenia is associated with subtle developmental compromise, but the degree to which this is also associated with heritability and genetic risk is uncertain. The goal of the current study was to investigate the childhood, adolescent, and early adulthood social and academic function of patients with schizophrenia, their healthy siblings, and normal controls, using the Premorbid Adjustment Scale (PAS). Generalized Estimating Equations were conducted to account for nesting of subjects within families. Patients (N=286) scored significantly worse than their healthy siblings (N=315) at every age period; siblings scored significantly worse than controls (N=261) at every age period. In probands, PAS scores got worse after early adolescence while control and proband scores improved after late adolescence. Furthermore, patient PAS scores significantly predicted the scores of their own discordant siblings in childhood and late adolescence. This effect approached significance in early adolescence and in the general scale. Thus, the most premorbidly impaired patients tended to have non-ill siblings with worse premorbid adjustment scores than the siblings of less impaired probands. The results suggest that both patients and many of their siblings share poor adjustment in childhood and adolescence, possibly due to shared genetic or environmental risk factors.

Serious obstetric complications interact with hypoxia-regulated/vascular-expression genes to influence schizophrenia risk

The etiology of schizophrenia is thought to include both epistasis and gene-environment interactions. We sought to test whether a set of schizophrenia candidate genes regulated by hypoxia or involved in vascular function in the brain (AKT1, BDNF, CAPON, CHRNA7, COMT, DTNBP1, GAD1, GRM3, NOTCH4, NRG1, PRODH, RGS4, TNF-alpha) interacted with serious obstetric complications to influence risk for schizophrenia. A family-based study of transmission disequilibrium was conducted in 116 trios. Twenty-nine probands had at least one serious obstetric complication (OC) using the McNeil-Sjostrom Scale, and many of the OCs reported were associated with the potential for fetal hypoxia. Analyses were conducted using conditional logistic regression and a likelihood ratio test (LRT) between nested models was performed to assess significance. Of the 13 genes examined, four (AKT1 (three SNPs), BDNF (two SNPs), DTNBP1 (one SNP) and GRM3 (one SNP)) showed significant evidence for gene-by-environment interaction (LRT P-values ranged from 0.011 to 0.037). Although our sample size was modest and the power to detect interactions was limited, we report significant evidence for genes involved in neurovascular function or regulated by hypoxia interacting with the presence of serious obstetric complications to increase risk for schizophrenia.

Comprehensive approach for correction of motion and distortion in diffusion-weighted MRI

Patient motion and image distortion induced by eddy currents cause artifacts in maps of diffusion parameters computed from diffusion-weighted (DW) images. A novel and comprehensive approach to correct for spatial misalignment of DW imaging (DWI) volumes acquired with different strengths and orientations of the diffusion sensitizing gradients is presented. This approach uses a mutual information-based registration technique and a spatial transformation model containing parameters that correct for eddy current-induced image distortion and rigid body motion in three dimensions. All parameters are optimized simultaneously for an accurate and fast solution to the registration problem. The images can also be registered to a normalized template with a single interpolation step without additional computational cost. Following registration, the signal amplitude of each DWI volume is corrected to account for size variations of the object produced by the distortion correction, and the b-matrices are properly recalculated to account for any rotation applied during registration. Both qualitative and quantitative results show that this approach produces a significant improvement of diffusion tensor imaging (DTI) data acquired in the human brain.

The neurodevelopmental hypothesis of schizophrenia: following a trail of evidence from cradle to grave

This is a critical review of the literature related to the neurodevelopmental hypothesis of schizophrenia which posits that the illness is related to abnormal brain development. The review focuses on data deriving from clinical studies, and it is organized according to the life phase from which the data were collected: conception and birth, infancy and childhood up to the onset of the illness, after illness onset, and postmortem. The neurodevelopmental hypothesis is supported by several pieces of evidence, including increased frequency of obstetric complications in patients with schizophrenia: the presence of minor physical anomalies; the presence of neurological, cognitive, and behavioral dysfunction long before illness onset; a course and outcome of the illness itself that is incompatible in most cases with a degenerative illness; the stability of brain structural measures over time; and the absence of postmortem evidence of neurodegeneration. A historical perspective on how this research accumulated and a section addressing important areas of future investigation are also provided. We conclude that schizophrenia is certainly not a degenerative brain disorder, and that it is likely that a brain insult in utero or at birth plays a role in its expression. Current evidence cannot completely exclude the role of environmental variables after birth. In addition, it is possible that other psychiatric disorders may also have a neurodevelopmental component.

PET study of competition between intravenous cocaine and [11C]raclopride at dopamine receptors in human subjects

OBJECTIVE

Animal data suggest that the strong euphoriant effects of cocaine are related to the drug's enhancement of available dopamine at the synaptic cleft. The authors' goal was to determine whether this mechanism is the same in humans because the development of putative pharmacological agents for treatment of cocaine dependence depends on this knowledge.

METHOD

Positron emission tomography with [11C]raclopride was used to examine the effects of the intravenous administration of 48 mg of cocaine (a typical "street" dose) on the occupancy of dopamine 2 receptors in the putamen of 11 self-identified intravenous drug abusers.

RESULTS

All 11 subjects reported subjective stimulation and euphoria in response to cocaine administration. Radioligand occupancy at dopamine receptors was decreased significantly after cocaine administration, suggesting that higher dopamine concentrations were competing at the receptor site.

CONCLUSIONS

These results support the concept of dopamine system involvement in human cocaine abuse.

Dopamine transporters are markedly reduced in Lesch-Nyhan disease in vivo

Dopamine (DA) deficiency has been implicated in Lesch-Nyhan disease (LND), a genetic disorder that is characterized by hyperuricemia, choreoathetosis, dystonia, and compulsive self-injury. To establish that DA deficiency is present in LND, the ligand WIN-35,428, which binds to DA transporters, was used to estimate the density of DA-containing neurons in the caudate and putamen of six patients with classic LND. Comparisons were made with 10 control subjects and 3 patients with Rett syndrome. Three methods were used to quantify the binding of the DA transporter so that its density could be estimated by a single dynamic positron emission tomography study. These approaches included the caudate- or putamen-to-cerebellum ratio of ligand at 80-90 min postinjection, kinetic analysis of the binding potential [Bmax/(Kd x Vd)] using the assumption of equal partition coefficients in the striatum and the cerebellum, and graphical analysis of the binding potential. Depending on the method of analysis, a 50-63% reduction of the binding to DA transporters in the caudate, and a 64-75% reduction in the putamen of the LND patients was observed compared to the normal control group. When LND patients were compared to Rett syndrome patients, similar reductions were found in the caudate (53-61%) and putamen (67-72%) in LND patients. Transporter binding in Rett syndrome patients was not significantly different from the normal controls. Finally, volumetric magnetic resonance imaging studies detected a 30% reduction in the caudate volume of LND patients. To ensure that a reduction in the caudate volume would not confound the results, a rigorous partial volume correction of the caudate time activity curve was performed. This correction resulted in an even greater decrease in the caudate-cerebellar ratio in LND patients when contrasted to controls. To our knowledge, these findings provide the first in vivo documentation of a dopaminergic reduction in LND and illustrate the role of positron emission tomography imaging in investigating neurodevelopmental disorders.

Positron emission tomography imaging of serotonin transporters in the human brain using [11C](+)McN5652

This paper presents the first Positron Emission Tomography (PET) images of the serotonin (5-hydroxytryptamine, 5-HT) transporter in the living human brain. PET imaging was performed in three healthy subjects after administration of [11C](+)McN5652 (the (+) enantiomer of trans-1,2,3,5,6,10 beta-hexahydro- 6-[4-(methylthio) phenyl]pyrrolo-[2,1-a] -isoquinolone), a radioligand previously shown to selectively label the 5-HT transporter in vivo in the mammalian (mouse and baboon) brain. To demonstrate the specificity of [11C](+)McN5652 binding, additional images were obtained in the same subjects after injection of [11C](-)McN5652, the pharmacologically inactive enantiomer, and, in two of the subjects, with [11C](+)McN5652 after pretreatment with the 5-HT uptake site blocker fluoxetine. Highest accumulation of [11C](+)McN5652 was observed in the midbrain, putamen, caudate nucleus, hypothalamus, and thalamus, regions known to contain high densities of 5-HT transporters. In these areas [11C](+)McN5652 concentrations rose steadily over 120 min. In contrast, with [11C](-)McN5652 and when the [11C](+)McN5652 binding was inhibited with fluoxetine, radioactivity concentrations declined after reaching a maximum (at 20 to 30 min). Inhibition studies with fluoxetine suggest that only with [11C](+)McN5652, there is specific binding. In the cerebellum, a region relatively void of 5-HT transporters, both [11C](+)McN5652 with and without fluoxetine block and [11C](-)McN5652 were released at approximately the same rate. The results of the studies indicate that [11C](+)McN5652 labels 5-HT transporter sites in the human brain. Quantitative PET imaging studies with this new tracer should provide valuable information on the status of these sites in health and disease.

Comparison of functional MR and H2 15O positron emission tomography in stimulation of the primary visual cortex

PURPOSE

To locate spoiled gradient-echo functional MR signal changes in relation to brain parenchyma.

METHODS

The region of the primary visual cortex was evaluated using functional MR and H2 15O positron emission tomography in each of six male subjects who were being visually stimulated by means of red light-emitting diode flash goggles.

RESULTS

The positron emission tomography technique demonstrated substantially greater relative signal change with visual stimulation than did the functional MR technique. Furthermore, the functional MR signal changes were concentrated in loci around the periphery of brain parenchyma exhibiting increased radiotracer activity, as opposed to being collocated.

CONCLUSIONS

Signal changes found using functional MR based on gradient-echo techniques reflect primarily phenomena occurring within small veins and underrepresent activity intrinsic to brain parenchyma, thus introducing potential inaccuracies in locating regions of activated brain tissue. Positron emission tomography, however, directly measures changes in metabolically related activity within the parenchyma.

Regional cerebral blood flow during the Wisconsin Card Sorting Test in normal subjects studied by xenon-133 dynamic SPECT: comparison of absolute values, percent distribution values, and covariance analysis

We studied regional cerebral blood flow (rCBF) by xenon-133 dynamic single photon emission computed tomography (SPECT) in 17 normal volunteers who were performing the Wisconsin Card Sorting Test (WCST), a task that is particularly sensitive to disturbance of the prefrontal cortex, and a simple matching-to-sample task (BAR) as a sensorimotor control. Three methods for statistical analysis of regional "subtraction" data were used: absolute rCBF values, percent distribution values, and means adjusted for global CBF changes (covariance analysis). The absolute values had high variance, due to the combination of interindividual differences in global flow and intra-individual variation, and showed no statistically significant regional changes. This variation was greatly reduced by percent values and covariance analysis, which had quite similar outcomes. With both methods, significant increases of rCBF during the WCST as compared with the BAR were seen in the right anterior dorsolateral prefrontal and left occipital cortices, and reduction of rCBF in the left pararolandic region. Moreover, significant correlations with performance were found in the medial regions of the frontal lobes, with opposite trends for the right and left hemisphere. The posterior dorsolateral prefrontal region showed a negative correlation with sensory-motor frequency, an index related to the task's difficulty. These results are consistent with previous findings using other rCBF techniques and confirm the statistical advantage of normalization and covariance methods, which yield practically identical results, at least in this analysis based on regions of interest.

Regional cerebral blood flow in chronic hypertension. A correlative study

BACKGROUND AND PURPOSE

Cerebral hypoperfusion has occasionally been reported during essential hypertension. We explored regional cerebral blood flow in a large series of neurologically asymptomatic hypertensive patients to determine relations among cerebral blood flow, concomitant main vascular risk factors, and the most common signs of end-organ damage.

METHODS

Regional cerebral blood flow was measured by the 133Xe inhalation method in 101 hypertensive patients without clinically apparent central nervous system involvement, including 39 mild to moderate untreated and 62 mild to severe treated patients.

RESULTS

Compared with age- and sex-matched normal control subjects, cerebral blood flow was significantly reduced in untreated hypertensive patients (P < .01) and to a lesser extent in treated patients (P = .047). Both regional and global cerebral blood flow reductions were observed in approximately one third of patients in both groups. Analysis of variance failed to show significant correlations between cerebral blood flow and total cholesterol concentration, mean arterial blood pressure, duration of disease, or the presence of retinopathy or left ventricular hypertrophy. In the treated group, the quality of control of hypertension significantly influenced both global cerebral blood flow (P = .007) and cerebrovascular resistance (P < .0001).

CONCLUSIONS

Focal or diffuse cerebral hypoperfusion is present even in neurologically asymptomatic hypertensive patients, especially when untreated; good control of blood pressure may preserve cerebral perfusion and reduce cerebrovascular resistance. Regional cerebral blood flow examination represents a relatively simple and low-cost technique to explore the perfusional condition of the brain, one of the main target organs of hypertensive disease.

Regional cerebral blood flow and cerebrovascular reactivity in IDDM

OBJECTIVE

To investigate both rCBF and cerebrovascular reactivity, evaluated as pre- and post-ACZ rCBF differences in a group of IDDM patients with differences in duration of disease and severity of complications.

RESEARCH DESIGN AND METHODS

rCBF was measured by the 133Xenon inhalation method in 20 IDDM patients and in 15 healthy control subjects before and after an intravenous injection of ACZ, a carbonic anhydrase inhibitor commonly used to assess cerebrovascular reactivity.

RESULTS

Basal global CBF (the mean of 32 regional values) was within the normal range in all patients but 1, who showed slight hyperperfusion; moreover, in 3 patients with long-lasting disease, some hypoperfused regions were found. ANOVA showed an inverse correlation between basal global CBF (P < 0.01) and duration of diabetes, but no correlation with Hb, MABP, serum glucose concentration, or GHb. Compared with control subjects, the percentage of global CBF increment after ACZ administration was significantly impaired in 4 patients and gave a borderline response in 2 patients; 4 of these poor ACZ responders had retinopathy, and 1 had suffered from a TIA. Duration of diabetes, Hb, MABP, serum glucose concentration, and GHb did not correlate with the percentage of post-ACZ global CBF changes, and did not differ among the 6 poor ACZ responders and the other diabetic patients or control subjects.

CONCLUSIONS

These results confirm that global CBF is within the normal range in most IDDM patients, although it is significantly influenced by the duration of diabetes; pathophysiological correlates of the altered cerebrovascular reactivity need to be further investigated. rCBF measurements, before and after ACZ administration, seem to represent a safe and reliable tool for assessing cerebrovascular function in IDDM.

Regional cerebral blood flow in chronic stroke patients

BACKGROUND AND PURPOSE

The aim of this study was to investigate regional cerebral blood flow parameters during the postacute phase of unilateral ischemic stroke and to correlate them with clinical data.

METHODS

Regional cerebral blood flow was measured in 187 patients in the stabilized phase of stroke by the xenon-133 inhalation method with 32 extracranial detectors. Thirty-eight patients were reexamined after a mean +/- SD time of 32 +/- 21.4 months.

RESULTS

The overall detection of hypoperfusion was 92.0%, with asymmetries as the most sensitive index, especially for patients with a lesser degree of neurological disability. Neurological disability score was strongly associated with regional cerebral blood flow in the affected hemisphere (p < 0.0001) and with asymmetries (p < 0.0001). The presence of carotid obstruction further decreased the regional cerebral blood flow in the affected hemisphere and significantly increased asymmetry (p < 0.0001). Subjects who had no hypoperfusion at absolute values analysis were more frequently free of carotid disease and had less severe disability than those who had bilateral or unilateral regional absolute cerebral blood flow reduction. In 38 patients without new cerebrovascular events, a significant (p = 0.005) reduction of hemispheric regional cerebral blood flow asymmetries was found on a follow-up examination.

CONCLUSIONS

These data confirm the value of regional cerebral blood flow asymmetries in stroke detection and point out that important clinical information is also contained in absolute values analysis.

A comparison of xenon-133 and xenon-127 for the determination of regional cerebral blood flow measured by dynamic SPECT

Phantom studies and cerebral blood flow (CBF) measurements in 11 normal subjects at rest were performed by single photon emission tomography (SPECT) with Xe-133 (16 mm full-width at half-maximum [FWHM] collimation) and Xe-127 (16 mm, 12 mm, and 9 mm FWHM collimation). The phantom results clearly illustrated the feasibility of Xe-127 studies and the advantage of Xe-127 over Xe-133 for equivalent patient dose exposures. CBF values obtained with Xe-127 were comparable to those of Xe-133 for the 16 mm collimator, although higher flow values were found with the better resolution, probably because of reduced partial volume effects. The correlations between the various groups of examinations were high, except for the Xe-133 and Xe-127 16 mm collimator groups. Xe-127 allows a considerable increase in the resolution of the images, while exposing the patient to a lower radiation dose. Potential limitations because of higher energy penetrating photons from Xe-127 were not observed in this specially shielded equipment.