Virtual surgical analysis: long-term cone beam computed tomography stability assessment of segmental bimaxillary surgery.

The assessment of the stability of orthognathic surgery is often time-consuming, relies on manual re-identification of anatomical landmarks, and has been based on short-term follow-up. The purpose of this study was to propose and validate a semi-automated approach for three-dimensional (3D) assessment of the long-term stability of segmental bimaxillary surgery. The approach was developed and validated using cone beam computed tomography scans obtained at 2 weeks and 2 years postoperative. The stability of the surgical outcome was calculated as 3D translational and rotational differences between the short- and long-term postoperative positions of the individual bone segments. To evaluate reliability, intra-class correlation coefficients were calculated at a 95% confidence interval on measurements of two observers. Ten class II and III patients (six male, four female; mean age 24.4 years), who underwent a combined three-piece Le Fort I osteotomy, bilateral sagittal split osteotomy, and genioplasty, were included in the study. Intra- and inter-observer reliability were excellent (range 0.82-0.99). The range of the mean absolute difference of the intra- and inter-observer translational and rotational measurements were 0.14 mm (0.13)-0.44 mm (0.50) and 0.20° (0.16)-0.92° (0.78). The approach has excellent reliability for 3D assessment of long-term stability of segmental bimaxillary surgery.

Autotransplantation of premolars: does surgeon experience matter?

Autotransplantation of premolars is a well-established method to rehabilitate aplasia of premolars. Nevertheless, with the introduction of titanium implants, not all surgical units offer this procedure. The aim of this study was to examine the predictability of autotransplantation of premolars on orthodontic indication as suggested by Andreasen et al., when performed by surgeons with or without prior experience of this procedure. A prospective protocol was implemented in 2001. All patients treated with autotransplantation of premolars during the years 2001-2015 were recalled to evaluate the long-term status of the teeth. The state of root development, need for endodontic treatment, presence of an apical pathology or ankylosis, and tooth loss were recorded. The results were divided into two groups according to the surgeon's experience: senior surgeons with prior training and experience in the procedure and junior surgeons without prior experience. A total of 89 teeth (66 patients) were treated. The mean observation time was 10.1 years (range 1.0-15.1 years). The long-term survival rate was 95%. No statistically significant difference between the results of the two groups of surgeons was found. Autotransplantation of premolars on orthodontic indication could be adopted successfully in the hospital setting regardless of surgeon experience.

Women with congenital factor VII deficiency: clinical phenotype and treatment options from two international studies.

INTRODUCTION: A paucity of data exists on the incidence, diagnosis and treatment of bleeding in women with inherited factor VII (FVII) deficiency. AIM: Here we report results of a comprehensive analysis from two international registries of patients with inherited FVII deficiency, depicting the clinical picture of this disorder in women and describing any gender-related differences. METHODS: A comprehensive analysis of two fully compatible, international registries of patients with inherited FVII deficiency (International Registry of Factor VII deficiency, IRF7; Seven Treatment Evaluation Registry, STER) was performed. RESULTS: In our cohort (N = 449; 215 male, 234 female), the higher prevalence of mucocutaneous bleeds in females strongly predicted ensuing gynaecological bleeding (hazard ratio = 12.8, 95% CI 1.68-97.6, P = 0.014). Menorrhagia was the most prevalent type of bleeding (46.4% of patients), and was the presentation symptom in 12% of cases. Replacement therapies administered were also analysed. For surgical procedures (n = 50), a receiver operator characteristic analysis showed that the minimal first dose of rFVIIa to avoid postsurgical bleeding during the first 24 hours was 22 µg kg(-1) , and no less than two administrations. Prophylaxis was reported in 25 women with excellent or effective outcomes when performed with a total weekly rFVIIa dose of 90 µg kg(-1) (divided as three doses). CONCLUSION: Women with FVII deficiency have a bleeding disorder mainly characterized by mucocutaneous bleeds, which predicts an increased risk of ensuing gynaecological bleeding. Systematic replacement therapy or long-term prophylaxis with rFVIIa may reduce the impact of menorrhagia on the reproductive system, iron loss and may avoid unnecessary hysterectomies.

Patient characteristics that influence efficacy of prophylaxis with rFVIII-FS three times per week: a subgroup analysis of the LIPLONG study.

Prospective data on the efficacy of secondary prophylaxis in adults with haemophilia A are limited. To analyse bleeding outcomes in the sucrose-formulated recombinant factor VIII [rFVIII-FS (control)] arm of the LIPLONG study, a randomized, double-blind, 52-week trial was conducted in patients with severe haemophilia A receiving prophylaxis with the investigational product BAY 79-4980 or rFVIII-FS. The per-protocol population of previously treated patients with severe haemophilia A without a history of inhibitors (n = 68 males; mean age, 34.4 years) received 25 IU kg−1 rFVIII-FS three times per week for a median of 50.7 weeks. Annualized bleeding rates were assessed and analysed according to predefined target joint status at study start, prestudy treatment type (prophylaxis vs. on demand), age (<30 or ≥30 years), geographical region, bleeding frequency during the previous 6 months and physical activity status during the study using the Student t-test. The annualized median (range) number of bleeds was 2.2 (0.0­23) bleeds per year. The median (range) number of bleeds per year was significantly lower in patient subgroups without vs. with target joints [0.5 (0.0­17.1) vs. 4.2 (0.0­22.8); P = 0.02] and in those with ≤9 vs. >9 bleeds during the previous 6 months [1.1 (0.0­19.2) vs. 5.3 (0.0­22.8); P = 0.01]. Following randomization to prophylaxis with rFVIII-FS, bleeding frequency was effectively reduced. Absence of target joints and prestudy bleeding frequency were predictors of a low bleeding frequency during prophylaxis treatment.

Long-standing prophylactic therapy vs. episodic treatment in young people with severe haemophilia: a comparison of age-matched Danish and Russian patients.

Two distinctly different substitution principles are commonly used in haemophilia: treatment at bleeding episodes only referred to as on-demand treatment, and prophylactic factor administration. The aim of the cross-sectional study which was undertaken in young patients suffering severe haemophilia A was to challenge our hypothesis that on-demand treatment is inferior to prophylactic substitution in prevention of chronic joint disease at young age. The method involved an investigation of 40 patients from Russia (n = 27) and Denmark (n = 13) born between 1975 and 1990 with no history of inhibitors; Russian patients had exclusively received factor VIII on demand, while Danish patients were managed with prophylactic treatment during a mean period of 16 years since median age of 5 years. The study endpoints were clinical joint scores, Quality of Life scores and functional independence scores. Matched by identical age (±1 year) 13 Danish and 13 Russian patients were compared, while 14 age similar Russian patients served as controls. Demographic data among all groups were quite comparable. The results are that Russian patients presented with clinical joint scores at 27 ± 8.5 (mean ± SD) while matched Danish counterparts scored 3.8 ± 5.3 (mean ± SD), differences being highly significant. The number of joint bleeds in recent 5 years were 199.5 ± 135 (mean ± SD) vs. 8.1 ± 8.7 (mean ± SD). Likewise, Quality of Life and functional independence scores were significantly higher in patients on prophylaxis as compared to on-demand treatment. In conclusion, the study outcomes confirmed our hypothesis. Longer term prophylactic factor administration during childhood and adolescence prevents joint destruction.

Platelet activation and aggregation: the importance of thrombin activity--a laboratory model.

This study introduces a new laboratory model of whole blood platelet aggregation stimulated by endogenously generated thrombin, and explores this aspect in haemophilia A in which impaired thrombin generation is a major hallmark. The method was established to measure platelet aggregation initiated by tissue factor evaluated by means of impedance aggregometry. Citrated whole blood from healthy volunteers and haemophilia A patients with the addition of inhibitors of the contact pathway and fibrin polymerization was evaluated. In healthy persons, a second wave of platelet aggregation was found to coincide with the thrombin burst and to be abolished by thrombin inhibitors. In this system, platelet aggregation in severe haemophilia A (n = 10) was found to be significantly decreased as compared with healthy individuals (912 ± 294 vs. 1917 ± 793 AU × min, P = 0.003), most probably due to the weak level of thrombin generation. For the first time, analysis of platelet aggregation as induced by endogenously generated thrombin was demonstrated. The new method makes it possible to explore the influence of the coagulation system on platelet function. In contrast to the general understanding, the data suggest that the impaired thrombin generation in haemophilia may affect platelet activation. Future studies will address whether our results may contribute to understanding differences in bleeding phenotypes and response to haemostatic substitution observed among patients.

Endothelial dysfunction, increased inflammation, and activated coagulation in HIV-infected patients improve after initiation of highly active antiretroviral therapy.

OBJECTIVES: Endothelial dysfunction and inflammation have been demonstrated to be markers of cardiovascular risk. We investigated the effects of HIV infection per se and the antiretroviral treatment prescribed on the levels of risk factors of cardiovascular disease. METHODS: This was a prospective study of 20 treatment-naïve, nonsmoking, HIV-positive patients examined before and after 3 months of treatment with a protease inhibitor (PI)-containing regimen followed by 3 months of treatment with nonnucleoside reverse transcriptase inhibitor (NNRTI)-containing therapy. Parameters of inflammation, endothelial function and coagulation were examined. The results were compared with those for an age- and gender-matched, nonsmoking, healthy control group. RESULTS: Compared with controls, treatment-naïve HIV-infected patients exhibited endothelial dysfunction [flow-mediated dilation (FMD) 108 vs. 111% for HIV-infected vs. control groups, respectively; P < 0.05] and activation [von Willebrand factor 2.0 vs. 0.9 U/l; soluble intercellular adhesion molecule (sICAM) 313 vs. 211 ng/L, respectively; P < 0.01]. Inflammation [C-reactive protein (CRP) 24 vs. 8.6 nmol/L; fibrinogen 9.4 vs. 8.6 µmol/L, respectively; P < 0.05] and coagulation/fibrinolysis (D-dimers 0.55 vs. 0.23 µg/mL, respectively; P < 0.01) were increased. Initiating therapy resulted in normalization of FMD and a significant decrease in endothelial activation and CRP. CONCLUSION: Endothelial dysfunction together with increased inflammation and coagulation were more prevalent in untreated HIV-infected patients compared with controls. These cardiovascular risk factors improved with treatment, although not all parameters normalized after 6 months.

Progression of haemophilic arthropathy in children: a Lithuanian--Danish comparative study.

Recurrent bleeding into joints initiates a sequence of events leading to a progressive joint damage in people with severe haemophilia. This is a continuous process during childhood and adolescence, therefore joint abnormalities may be minimal on physical examination in very young children - even those receiving on-demand treatment. The aim of our study was to quantify the burden of arthropathy in Lithuanian patients who had been treated exclusively by on-demand substitution and compare their physical joint health with age-matched Danish patients who received prophylaxis from an early age. Boys, aged 4-17 years, with severe haemophilia and no signs of inhibitors were included in the study. Joint outcome based on the Haemophilia Joint Health Score (HJHS) was analysed in two different treatment groups and compared within the matched pairs. In total, 32 (16 in each treatment group) patients were enroled. A total of 192 joints were evaluated. Joint status according to treatment strategy was strikingly different: 27.4 for on-demand vs. 3.3 for prophylaxis (<0.001) group. Significance of the difference in joint status comparing different treatment strategies was equally strong both in younger (4-9 years) and older (10-17 years) patient groups: 2.2 vs. 12.5 (P = 0.0002) and 3.9 vs. 36.3 (P < 0.0001) respectively. The results further demonstrate the unequivocal effect of prophylaxis on joint status and give an insight into early and late manifestations of joint impairment based on the HJHS in haemophilia patients with treatment on-demand compared with joint changes that may develop over the time with the preventative treatment.

Malignant disease in the haemophilic population: moving towards a management consensus?

The Malignancy in Haemophilia Workshop Group convened a consensus working group of haematologists and oncologists to review topics related to malignancy in haemophilia. The treatment of malignant disease in this population is increasingly relevant as both outcome and lifespan continue to improve. Although adequate guidance exists for control of spontaneous bleeding episodes and of haemostasis in general surgery, information for management of haemostasis in patients with various malignancies is sparse. To date, no clinical guidelines exist for management of complex bleeding problems, diagnosis, therapy and follow-up of malignancies in haemophilia. Furthermore, it remains unclear whether or not morbidity and mortality outcomes associated with malignancies are affected by haemophilia or by its treatment. Through presentation of five malignancies - prostate cancer, colorectal cancer, acute leukaemia, bladder cancer and hepatocellular carcinoma - important issues are highlighted, such as risk from bleeding as a symptom of malignancy; risks from invasive screenings and how these should be handled in haemophilic individuals; the implications of chemotherapy and treatment schedules, bone marrow suppression, radiotherapy, or surgery; and the likelihood of an interaction between treatment for haemophilia and malignancy outcomes. Ultimately, the aim is to establish consensus guidelines to direct and harmonize future treatment policy for malignant disease in the haemophilic population.

Coagulation factor activity and clinical bleeding severity in rare bleeding disorders: results from the European Network of Rare Bleeding Disorders.

BACKGROUND: The European Network of Rare Bleeding Disorders (EN-RBD) was established to bridge the gap between knowledge and practise in the care of patients with RBDs. OBJECTIVES: To explore the relationship between coagulation factor activity level and bleeding severity in patients with RBDs. PATIENTS/METHODS: Cross-sectional study using data from 489 patients registered in the EN-RBD. Coagulation factor activity levels were retrieved. Clinical bleeding episodes were classified into four categories according to severity. RESULTS: The mean age of patients at data collection was 31 years (range, 7 months to 95 years), with an equal sex distribution. On linear regression analysis, there was a strong association between coagulation factor activity level and clinical bleeding severity for fibrinogen, factor (F) X, FXIII, and combined FV and FVIII deficiencies. A weaker association was present for FV and FVII deficiencies. There was no association between coagulation factor activity level and clinical bleeding severity for FXI. The coagulation factor activity levels that were necessary for patients to remain asymptomatic were: fibrinogen, > 100 mg dL(-1); FV, 12 U dL(-1); combined FV + VIII, 43 U dL(-1); FVII, 25 U dL(-1); FX, 56 U dL(-1) ; FXI, 26 U dL(-1); FXIII, 31 U dL(-1). Moreover, coagulation factor activity levels that corresponded with Grade III bleeding were: undetectable levels for fibrinogen, FV and FXIII, < 15 U dL(-1) for combined FV + VIII; < 8 U dL(-1) for FVI; < 10 U dL(-1) for FX; and < 25 U dL(-1) for FXI. CONCLUSIONS: There is a heterogeneous association between coagulation factor activity level and clinical bleeding severity in different RBDs. A strong association is only observed in fibrinogen, FX and FXIII deficiencies.

Dynamic APTT parameters: applications in thrombophilia.

BACKGROUND: Patients with a history of venous thrombosis occasionally have shortened APTTs when compared with those of healthy references, but the clinical applicability of a shortened APTT is limited. OBJECTIVES: The present study aimed to characterize dynamic APTT profiles in patients with previously documented venous thrombosis and hypothesized that the APTT-MaxVel was significantly elevated in patients with a history of venous thrombosis as compared with healthy controls. METHODS: We performed a case control study, enrolling a total of 38 patients, 17 males and 21 females, with a verified recent venous thrombotic event, as well as 88 healthy controls. Fifty-three per cent of patients were found to have a biochemical risk factor. A standard APTT was recorded in platelet-poor plasma, and the digital clotting signal was processed using simple algorithms developed to derive dynamic coagulation parameters. RESULTS: Patients had a significantly higher mean APTT-MaxVel (195.5 s(-1) ; SD = 57; 95% CI, 176.8-214.1) as compared with healthy controls (137.3 s(-1) ; SD = 21; 95% CI, 130.7-143.8). Patients also had significantly shorter mean APTTs (26.9 s; SD = 3.2; 95% CI, 25.9-28.0) than healthy controls (28.5 s; SD = 2.8; 95% CI, 27.9-29.0). While only one out of 38 patients (2.6%) had a standard APTT below the lower reference interval, 15 of the 38 patients (38.5%) had an APTT-MaxVel above the upper reference limit. Regression analysis revealed linear correlation between FVIII:C, the level of fibrinogen and APTT-MaxVel (R(2) = 0.89, P < 0.05). CONCLUSIONS: Simple signal processing of the APTT and the use of dynamic parameters represents a stronger predictive marker for hypercoagulation in patients with verified venous thrombosis than the standard APTT measurement.

Previously unrecognized advanced liver disease unveiled by transient elastography in patients with Haemophilia and chronic hepatitis C.

Before the introduction of viral inactivation procedures and viral screening of plasma-products, haemophiliacs were at high risk of infection with HCV. Those who acquired HCV infection in the 1980s, and are still alive today, may have developed significant liver fibrosis or cirrhosis. However, liver biopsy has not routinely been utilized in the evaluation of haemophiliacs with HCV in Denmark. The aim of this study was to investigate the prevalence of significant fibrosis/cirrhosis among haemophiliacs as evaluated by transient elastography (TE). Cross-sectional investigation of adult patients with haemophilia A or B. TE with liver stiffness measurements (LSM) ≥ 8 kPa were repeated after 4-6 weeks. Significant fibrosis and cirrhosis was defined as measurements ≥ 8 kPa or ≥ 12 kPa respectively. Among 307 patients with haemophilia A or B registered at the two Haemophilia centres, 141(46%) participate in this study. Forty (28.4%) had chronic hepatitis C, 33 (23.4%) past hepatitis C and 68 (48.2%) had never been infected, at screening LSM ≥ 8 kPa were found in 45.7%, 24.7% and 4.6% respectively. Among patients with chronic hepatitis C significant fibrosis was confirmed in 17.1% and cirrhosis in 2.9% by repeated LSM ≥ 8 and ≥ 12 kPa respectively. The median TE-value in never HCV-infected haemophiliacs was comparable with what has been found in healthy non-haemophiliacs. In Danish haemophiliacs where liver biopsy has not routinely been used for assessing severity of liver fibrosis, LSM identified advanced liver disease in one-fifth of cases that had not been recognized during clinical follow-up.

Standardization of thromboelastography: a report from the TEG-ROTEM working group.

Laboratory evaluation of bleeding disorders has been performed with the standard clotting assays such as the PT and PTT for several decades. Our improved understanding of the process of blood coagulation has now revealed the important role played by the cellular elements such as platelets, monocytes and red blood cells. The need for a test that can assess clotting in a more 'global' manner, beyond the initiation of clot formation, has led to greater interest in assays such as thrombin generation and thromboelastography. Even though there are several publications using thromboelastography it remains a research tool as the methodology is not standardized. In an attempt to show reproducibility and consistency using thromboelastography, a group of investigators from different countries joined hands to form the TEG-ROTEM Working Group. Two studies were performed using PRP and FVIII deficient plasma and an intrinsic pathway activator. This article summarizes the results of the first international effort at standardization of thromboelastography. Both of the instruments using this technology (TEG(®) and ROTEM(®)) were used. Nine laboratories from countries around the globe participated in this effort. The results showed a significant inter-laboratory variance with CV's greater than 10%. Although these results were not satisfactory, this has been the first effort to standardize this methodology and significant work remains to be done to improve reliability and reproducibility. These studies were performed on PRP and the results may be more reliable when preformed on whole blood samples. We believe that it is important to continue this work so that we may investigate the usefulness and potential applications of thromboelastography in the evaluation of bleeding and thrombosis.

Factor XIII combined with recombinant factor VIIa: a new means of treating severe hemophilia A.

BACKGROUND: Abnormal thrombin generation is considered the key defect in hemophilia. Conventional treatment seeks to correct this using coagulation factor replacement or bypassing agents, for example recombinant factor VIIa (rFVIIa). Previous studies demonstrate abnormal FXIII activation in patients with hemophilia. FXIII activation is essential for formation of structurally normal, stable clots. OBJECTIVES: The present study challenges the hypothesis that in hemophilia the use of plasma-derived FXIII (pdFXIII) in combination with rFVIIa will produce a greater improvement in clot stability than promotion of thrombin generation alone. METHODS: Fourteen individuals with severe hemophila A were enrolled. Whole blood was spiked ex vivo with buffer, rFVIIa (2 µg mL(-1)) or rFVIIa (2 µg mL(-1)) plus pdFXIII (10 µg mL(-1)). Whole blood thromboelastometry assessed clot stability, after activation with tissue factor (TF) (0.15 pm) plus tissue-type plasminogen activator (tPa) (2 nm). The primary outcome measure of clot stability was area under the elasticity curve (AUEC). RESULTS: The combination of pdFXIII and rFVIIa significantly improved clot stability as measured by AUEC (P < 0.05) compared with rFVIIa alone. CONCLUSION: The use of pdFXIII resulted in superior clot stability compared with solely enhancing thrombin generation and we suggest that increasing thrombin generation alone fails to fully correct dysregulation of clot-stabilizing mechanisms associated with bleeding disorders. Hemorrhage control in hemophilia may be improved using clot stabilizing drugs. FXIII shows potential as a novel agent.

Validation of a rapid test (VWF-LIA) for the quantitative determination of von Willebrand factor antigen in type 1 von Willebrand disease diagnosis within the European multicenter study MCMDM-1VWD.

BACKGROUND: Accurate measurement of von Willebrand factor (VWF) is a critical requirement for the diagnosis of von Willebrand disease (VWD). AIM OF THE STUDY: To evaluate the diagnostic efficiency of a rapid quantitative test for the measurement of VWF antigen (VWF:Ag) in type 1 VWD. PATIENTS AND METHODS: VWF:Ag was measured with an ELISA in a robotic instrument, as a reference method, and with a fully automated latex-immunoassay (LIA) on an ACL 9000 analyser in 1,716 subjects enrolled within the Molecular and Clinical Markers for Diagnosis and Management of Type 1 von Willebrand Disease (MCMDM-1VWD) Study. Among these subjects, 1,049 were healthy controls, 281 healthy family members and 386 affected members from 127 European families with type 1 VWD. RESULTS: The assay linearity range was 10-125 IU/dL for LIA (R2=0.99) and 5-133 IU/dL for ELISA (R2=0.99). The inter-assay CV for low VWF levels (approximately 30 IU/dL) was 2% for the LIA test and 8.7 % for ELISA. The sensitivity for detection of type 1 VWD affected members was 86% and the specificity 91% for LIA, 87% and 90% for ELISA. A receiver-operator (ROC) analysis disclosed only a marginal difference between the two tests, LIA having a slightly greater area under the curve (0.94 vs. 0.93, p=0.03). CONCLUSION: VWF:Ag LIA compared well to standard ELISA in this large population of patients and controls, showing better CV. However the lower detection limit for the VWF:Ag LIA compared to the VWF:Ag ELISA means that the LIA assay is less good at discriminating between type 3 VWD and moderate type 1 VWD.