Regenerative Peripheral Nerve Interface: Surgical Protocol for a Randomized Controlled Trial in Postamputation Pain

Surgical procedures, including nerve reconstruction and end-organ muscle reinnervation, have become more prominent in the prosthetic field over the past decade. Primarily developed to increase the functionality of prosthetic limbs, these surgical procedures have also been found to reduce postamputation neuropathic pain. Today, some of these procedures are performed more frequently for the management and prevention of postamputation pain than for prosthetic fitting, indicating a significant need for effective solutions to postamputation pain. One notable emerging procedure in this context is the Regenerative Peripheral Nerve Interface (RPNI). RPNI surgery involves an operative approach that entails splitting the nerve end longitudinally into its main fascicles and implanting these fascicles within free denervated and devascularized muscle grafts. The RPNI procedure takes a proactive stance in addressing freshly cut nerve endings, facilitating painful neuroma prevention and treatment by enabling the nerve to regenerate and innervate an end organ, i.e., the free muscle graft. Retrospective studies have shown RPNI's effectiveness in alleviating postamputation pain and preventing the formation of painful neuromas. The increasing frequency of utilization of this approach has also given rise to variations in the technique. This article aims to provide a step-by-step description of the RPNI procedure, which will serve as the standardized procedure employed in an international, randomized controlled trial (ClinicalTrials.gov, NCT05009394). In this trial, RPNI is compared to two other surgical procedures for postamputation pain management, specifically, Targeted Muscle Reinnervation (TMR) and neuroma excision coupled with intra-muscular transposition and burying.

Targeted Muscle Reinnervation: Surgical Protocol for a Randomized Controlled Trial in Postamputation Pain

Over the past decade, the field of prosthetics has witnessed significant progress, particularly in the development of surgical techniques to enhance the functionality of prosthetic limbs. Notably, novel surgical interventions have had an additional positive outcome, as individuals with amputations have reported neuropathic pain relief after undergoing such procedures. Subsequently, surgical techniques have gained increased prominence in the treatment of postamputation pain, including one such surgical advancement - targeted muscle reinnervation (TMR). TMR involves a surgical approach that reroutes severed nerves as a type of nerve transfer to "target" motor nerves and their accompanying motor end plates within nearby muscles. This technique originally aimed to create new myoelectric sites for amplified electromyography (EMG) signals to enhance prosthetic intuitive control. Subsequent work showed that TMR also could prevent the formation of painful neuromas as well as reduce postamputation neuropathic pain (e.g., Residual and Phantom Limb Pain). Indeed, multiple studies have demonstrated TMR's effectiveness in mitigating postamputation pain as well as improving prosthetic functional outcomes. However, technical variations in the procedure have been identified as it is adopted by clinics worldwide. The purpose of this article is to provide a detailed step-by-step description of the TMR procedure, serving as the foundation for an international, randomized controlled trial (ClinicalTrials.gov, NCT05009394), including nine clinics in seven countries. In this trial, TMR and two other surgical techniques for managing postamputation pain will be evaluated.

Idiopathic Fistula in an Unrepaired Submucous Cleft Palate

Palatal fistulae are a recognised complication in individuals who have undergone surgical repair of a cleft palate, however, congenital or idiopathic palatal fistulae are rare. This report discusses the presentation and treatment of a 16-year-old female with a submucous cleft palate, who presented with a recent onset change in speech and evidence of a new palatal fistula. There was no history of recent infection or known trauma, and the patient had not undergone any previous palatal surgery. This report discusses the clinical presentation, recommended management and relevant literature for this rare phenomenon.

Surgical treatments for postamputation pain: study protocol for an international, double-blind, randomised controlled trial

BACKGROUND

Painful conditions such as residual limb pain (RLP) and phantom limb pain (PLP) can manifest after amputation. The mechanisms underlying such postamputation pains are diverse and should be addressed accordingly. Different surgical treatment methods have shown potential for alleviating RLP due to neuroma formation - commonly known as neuroma pain - and to a lesser degree PLP. Two reconstructive surgical interventions, namely targeted muscle reinnervation (TMR) and regenerative peripheral nerve interface (RPNI), are gaining popularity in postamputation pain treatment with promising results. However, these two methods have not been directly compared in a randomised controlled trial (RCT). Here, we present a study protocol for an international, double-blind, RCT to assess the effectiveness of TMR, RPNI, and a non-reconstructive procedure called neuroma transposition (active control) in alleviating RLP, neuroma pain, and PLP.

METHODS

One hundred ten upper and lower limb amputees suffering from RLP will be recruited and assigned randomly to one of the surgical interventions (TMR, RPNI, or neuroma transposition) in an equal allocation ratio. Complete evaluations will be performed during a baseline period prior to the surgical intervention, and follow-ups will be conducted in short term (1, 3, 6, and 12 months post-surgery) and in long term (2 and 4 years post-surgery). After the 12-month follow-up, the study will be unblinded for the evaluator and the participants. If the participant is unsatisfied with the outcome of the treatment at that time, further treatment including one of the other procedures will be discussed in consultation with the clinical investigator at that site.

DISCUSSION

A double-blind RCT is necessary for the establishment of evidence-based procedures, hence the motivation for this work. In addition, studies on pain are challenging due to the subjectivity of the experience and the lack of objective evaluation methods. Here, we mitigate this problem by including different pain evaluation methods known to have clinical relevance. We plan to analyse the primary variable, mean change in NRS (0-10) between baseline and the 12-month follow-up, using the intention-to-treat (ITT) approach to minimise bias and keep the advantage of randomisation. The secondary outcomes will be analysed on both ITT and per-protocol (PP). An adherence protocol (PP population) analysis will be used for estimating a more realistic effect of treatment.

TRIAL REGISTRATION

ClincialTrials.gov NCT05009394.

352 THE IMPACT OF ETHNICITY ON ACUTE STROKE ADMISSIONS IN AN IRISH HOSPITAL

Background

Recent studies have demonstrated the variability of aetiology, clinical presentation and overall mortality between different ethnic groups presenting with acute stroke. The non-native Irish population accounts for almost 13% of the total population and is predicted to grow over the next decade. Recording and analysis of acute stroke patients based on their ethnicity and population demographics is an important step in planning for the future of stroke care in Ireland. In this study, we aimed to evaluate key differences between the Irish and non-Irish population presenting with acute stroke to an Irish hospital.

Methods

We reviewed our hospital stroke registry over a 12-month period (January-December 2021). Key parameters including country of birth, ethnicity, other patient demographics, clinical presentation, aetiology and subtype of stroke, stroke management and clinical outcomes.

Results

Of the 245 acute strokes admitted to our hospital in 2021, non-ethically Irish patients made up 12.2% (n = 30). The average age of non-ethnically Irish stroke presentations was younger than Irish stroke presentations (59 versus 71 years). Haemorrhagic strokes were more common in the non-Irish population (13.3% in non-Irish cohort vs 9.8% in Irish cohort). Median time of symptom onset to presentation to hospital was 3 hours and 58 minutes in the Irish patients and 6 hours and 10 minutes in the non-Irish patients. The overall length of stay in hospital post stroke was similar between the two population groups at an average of 19 days duration.

Conclusion

This study identifies disparities in acute stroke presentation between the Irish and non-Irish population presenting to an Irish hospital. This study demonstrated the importance of further research on a national scale to record the variability of strokes in different ethnic groups in order to adequately plan primary and secondary stroke care and provide targeted public health campaigns to remain inclusive to Ireland’s growing and increasingly diverse population.

Comparison of Patient Satisfaction on a Day-case Mastectomy Pathway for Breast Cancer Versus a Traditional Inpatient Delivery Model, Using a Validated Questionnaire

BACKGROUND

In 2011, a guidance was issued by the National Health Service (NHS) Improvement a model on how mastectomy could be offered in the day-case setting. The goal of this guidance was to reduce inpatient bed days and cost to the NHS, and demonstrate that it can be performed within an acceptable safety profile. The aim of this study was to assess whether patients find the day-case pathway for mastectomy an acceptable management model. We compared complication rates between the day-case and inpatient delivery model.

PATIENTS AND METHODS

This study was a retrospective analysis of patients' experience undergoing day-case (n=26) and inpatient mastectomy (n=60). The primary outcome measure was based on a telephone interview using a validated, standardised questionnaire.

RESULTS

No statistically significant difference in the satisfaction levels between the two groups (raw scores 6.76 day-case vs. 6.15 inpatient, p=0.37) was demonstrated. We found no statistically significant difference between the two groups when specifically analysing whether patients found the first night harder as a day-case or inpatient (3.192 vs. 2.80, p=0.59, range 0-10). Our overall complications were 11.4% (day-case) and 18.3% (inpatients). Rates were comparable between the two groups and equivalent to published rates in the literature.

CONCLUSION

There was no statistically significant difference in satisfaction scores between patients who had a mastectomy as an inpatient versus those who had their operation as a day-case procedure. In addition, there were no significant differences in the complication rates between the two groups. We conclude then that it is feasible and safe to offer day-case mastectomy, with no loss in patient satisfaction.

Blood CD9+ B cell, a biomarker of bronchiolitis obliterans syndrome after lung transplantation

Bronchiolitis obliterans syndrome is the main limitation for long-term survival after lung transplantation. Some specific B cell populations are associated with long-term graft acceptance. We aimed to monitor the B cell profile during early development of bronchiolitis obliterans syndrome after lung transplantation. The B cell longitudinal profile was analyzed in peripheral blood mononuclear cells from patients with bronchiolitis obliterans syndrome and patients who remained stable over 3 years of follow-up. CD24^hi CD38^hi transitional B cells were increased in stable patients only, and reached a peak 24 months after transplantation, whereas they remained unchanged in patients who developed a bronchiolitis obliterans syndrome. These CD24^hi CD38^hi transitional B cells specifically secrete IL-10 and express CD9. Thus, patients with a total CD9⁺ B cell frequency below 6.6% displayed significantly higher incidence of bronchiolitis obliterans syndrome (AUC = 0.836, PPV = 0.75, NPV = 1). These data are the first to associate IL-10-secreting CD24^hi CD38^hi transitional B cells expressing CD9 with better allograft outcome in lung transplant recipients. CD9-expressing B cells appear as a contributor to a favorable environment essential for the maintenance of long-term stable graft function and as a new predictive biomarker of bronchiolitis obliterans syndrome-free survival.

Personalized pathology maps to quantify diffuse and focal brain damage

Background and objectives

Quantitative MRI (qMRI) permits the quantification of brain changes compatible with inflammation, degeneration and repair in multiple sclerosis (MS) patients. In this study, we propose a new method to provide personalized maps of tissue alterations and longitudinal brain changes based on different qMRI metrics, which provide complementary information about brain pathology.

Methods

We performed baseline and two-years follow-up on (i) 13 relapsing-remitting MS patients and (ii) four healthy controls. A group consisting of up to 65 healthy controls was used to compute the reference distribution of qMRI metrics in healthy tissue. All subjects underwent 3T MRI examinations including T1, T2, T2* relaxation and Magnetization Transfer Ratio (MTR) imaging. We used a recent partial volume estimation algorithm to estimate the concentration of different brain tissue types on T1 maps; then, we computed a deviation map (z-score map) for each contrast at both time-points. Finally, we subtracted those deviation maps only for voxels showing a significant difference with healthy tissue in one of the time points, to obtain a difference map for each subject.

Results and conclusion

Control subjects did not show any significant z-score deviations or longitudinal z-score changes. On the other hand, MS patients showed brain regions with cross-sectional and longitudinal concomitant increase in T1, T2, T2* z-scores and decrease of MTR z-scores, suggesting brain tissue degeneration/loss. In the lesion periphery, we observed areas with cross-sectional and longitudinal decreased T1/T2 and slight decrease in T2* most likely related to iron accumulation. Moreover, we measured longitudinal decrease in T1, T2 - and to a lesser extent in T2* - as well as a concomitant increase in MTR, suggesting remyelination/repair.

In summary, we have developed a method that provides whole-brain personalized maps of cross-sectional and longitudinal changes in MS patients, which are computed in patient space. These maps may open new perspectives to complement and support radiological evaluation of brain damage for a given patient.

Prise en charge de l'embolie pulmonaire grave en réanimation

L'embolie pulmonaire (EP) grave, définie par la présence d’un état de choc, est à l'origine d'une mortalité importante. L'objectif de cette mise au point est de synthétiser les dernières avancées et recommandations concernant la prise en charge des formes graves d'EP. La stratification du risque individuel de mortalité précoce permet d'apporter une stratégie diagnostique et thérapeutique optimisée pour chaque patient. Le traitement symptomatique consiste essentiellement en la prise en charge de l'état de choc. L'anticoagulation curative par héparine non fractionnée est réservée aux patients hémodynamiquement instables. Chez ces patients à haut risque, la thrombolyse systémique diminue la mortalité et le risque de récidive d'EP. Chez les patients à risque intermédiaire élevé, la thrombolyse systémique à dose standard diminue le risque de choc secondaire mais sans impact sur la mortalité globale. La thrombolyse est donc réservée aux patients à risque intermédiaire élevé présentant secondairement un état de choc. L'embolectomie chirurgicale reste indiquée en cas de contre-indication absolue à la thrombolyse ou en cas d'échec de celle-ci. Le positionnement dans l'algorithme thérapeutique de l'assistance extracorporelle et des techniques percutanées de revascularisation reste à définir. Leurs indications doivent donc être discutées dans des centres experts après une concertation multidisciplinaire incluant pneumologues, cardiologues, réanimateurs, radiologues interventionnels et chirurgiens cardiaques.

Is there still room for additional common susceptibility alleles for venous thromboembolism?

Essentials Genetic architecture of venous thromboembolism (VTE) remains to be fully disentangled. 11 newly discovered candidate polymorphisms were genotyped in 3019 VTE cases and 2605 controls. None of the 11 polymorphisms were significantly associated with VTE risk. Additional major efforts are needed to identify VTE-associated genetic variants.

SUMMARY

Background Through a meta-analysis of 12 genome-wide association studies, the International Network against VENous Thrombosis (INVENT) consortium identified two novel susceptibility loci for venous thromboembolism (VTE). This project has also generated other candidates that need to be confirmed. Objectives To assess the association with VTE of common single-nucleotide polymorphisms (SNPs) that demonstrated strong statistical, but not genome-wide, significance in the INVENT cohorts. Patients/methods Eleven SNPs were genotyped and tested for association with VTE in three case-control studies totaling 3019 patients and 2605 healthy individuals. Results and conclusions None of the tested SNPs showed evidence for association with VTE. Different strategies are needed to decipher the whole spectrum of common and rare genetic variations associated with VTE risk.

Transluminal Angioplasty of a Stenotic Surgical Splenorenal Shunt

A stenosis of a side-to-side splenorenal shunt was treated by percutaneous angioplasty two years after the performance of the shunt. After dilatation, there was a fall of the splenorenal pressure gradient from 28 to 17 cm H2O and good transanastomotic flow was re-established. As in other arterial and venous territories, angioplasty may be an interesting alternative to surgery.

Laser treatment for female facial hirsutism: are quality-of-life benefits sustainable?

BACKGROUND

Facial hirsutism in women impairs quality of life (QoL). Laser hair removal (LHR) has been shown to confer significant improvements in QoL for up to 6 months after treatment, but the longer-term benefits have not been investigated.

AIM

To assess the sustainability of LHR benefits to the QoL of hirsute women up to 30 months after treatment.

METHODS

Hirsute women about to undergo National Health Service (NHS)-funded LHR in 2010-2012 (n = 142) completed proforma questionnaires quantifying the burden of hirsutism on their QoL. These included: the Dermatology Life Quality Index (DLQI) (assessing functional impact on QoL), the number of days spent removing hair per week and a 10-point scale assessing how much their condition bothered them (emotional burden on QoL). Postal questionnaires recorded QoL changes up to 30 months after LHR. Improvements in QoL scores for each woman were compared. Responses were then grouped into periods of 0-6, 6-12 and 12-30 months post-treatment, and the magnitude of change between these time groups was compared for each QoL measure.

RESULTS

In total, 63 women responded to the post-LHR questionnaire. QoL was severely affected, but improved with LHR. The number of days spent removing hair reverted to baseline at 12-30 months post-LHR, and a significant decline was seen in the magnitude of improvement in emotional burden on QoL over time (P = 0.04). However, no significant difference existed between improvements in DLQI scores (P = 0.12).

CONCLUSION

LHR supplies some functional QoL benefits up to 30 months post-treatment. Emotional benefits are less sustainable. Further LHR treatment is required to maintain QoL benefits.

A multi-contrast MRI study of microstructural brain damage in patients with mild cognitive impairment

Objectives

The aim of this study was to investigate pathological mechanisms underlying brain tissue alterations in mild cognitive impairment (MCI) using multi-contrast 3 T magnetic resonance imaging (MRI).

Methods

Forty-two MCI patients and 77 healthy controls (HC) underwent T1/T2* relaxometry as well as Magnetization Transfer (MT) MRI. Between-groups comparisons in MRI metrics were performed using permutation-based tests. Using MRI data, a generalized linear model (GLM) was computed to predict clinical performance and a support-vector machine (SVM) classification was used to classify MCI and HC subjects.

Results

Multi-parametric MRI data showed microstructural brain alterations in MCI patients vs HC that might be interpreted as: (i) a broad loss of myelin/cellular proteins and tissue microstructure in the hippocampus (p ≤ 0.01) and global white matter (p < 0.05); and (ii) iron accumulation in the pallidus nucleus (p ≤ 0.05). MRI metrics accurately predicted memory and executive performances in patients (p ≤ 0.005). SVM classification reached an accuracy of 75% to separate MCI and HC, and performed best using both volumes and T1/T2*/MT metrics.

Conclusion

Multi-contrast MRI appears to be a promising approach to infer pathophysiological mechanisms leading to brain tissue alterations in MCI. Likewise, parametric MRI data provide powerful correlates of cognitive deficits and improve automatic disease classification based on morphometric features.

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Forty-two MCI patients and 77 HC underwent multi-contrast quantitative MRI.

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MCI patients showed T1/T2* increase and MTR decrease in the hippocampus.

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MCI patients exhibited T1 increase in WM and T2* decrease in the pallidus.

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MRI metrics accurately predicted memory and executive function in patients.

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SVM classified MCI patients with 75% accuracy using volumetric/parametric MRI.

Primary prophylaxis for venous thromboembolism in people undergoing major amputation of the lower extremity

BACKGROUND

Patients undergoing major amputation of the lower limb are at increased risk of venous thromboembolism (VTE). Risk factors for VTE in amputees include advanced age, sedentary lifestyle, longstanding arterial disease and an identifiable hypercoagulable condition. Evidence suggests that pharmacological prophylaxis (for example heparin, factor Xa inhibitors, vitamin K antagonists, direct thrombin inhibitors, antiplatelets) is effective in preventing deep vein thrombosis (DVT) but it is associated with an increased risk of bleeding. Mechanical prophylaxis (for example antiembolism stockings, intermittent pneumatic compression and foot impulse devices), on the other hand, is non-invasive and has no side effects. However, it is not always appropriate in patients with contraindications such as peripheral arterial disease (PAD), arteriosclerosis or bilateral lower limb amputations. It is important to determine the most effective thromboprophylaxis and whether this is one treatment alone or in combination with another. To date, no systematic review has been conducted examining the effectiveness of thromboprophylaxis in preventing VTE in people undergoing amputation.

OBJECTIVES

To determine the effectiveness of thromboprophylaxis in preventing VTE in people undergoing major amputation of the lower extremity.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched May 2013) and CENTRAL (2013, Issue 4). Clinical trials databases were searched (May 2013). No date or language restrictions were applied. Non-English trials were translated where required and reference lists of identified studies were handsearched.

SELECTION CRITERIA

Randomised controlled trials and quasi-randomised controlled trials in which people undergoing a major unilateral or bilateral amputation (for example hip disarticulation, transfemoral, knee disarticulation and transtibial) of the lower extremity were allocated to different types or regimens of thromboprophylaxis (including pharmacological or mechanical prophylaxis) or placebo.

DATA COLLECTION AND ANALYSIS

Selection of studies, data extraction and risk of bias were completed independently by two review authors. Any disagreements were resolved by discussion. Meta-analysis could not be completed as the two included studies compared different treatments and therefore the data could not be pooled.

MAIN RESULTS

Two studies with a combined total of 288 participants met the inclusion criteria for this review. One study compared low molecular weight heparin with unfractionated heparin and found no difference between the treatments in the prevention of DVT (odds ratio (OR) 1.23, 95% confidence interval (CI) 0.28 to 5.35). No bleeding events or deaths occurred. This study was open label and therefore at a high risk of performance bias. Additionally, the method of randomisation was not reported and therefore the risk of selection bias was unclear. In the second study heparin did not significantly improve prevention of pulmonary embolism (OR 1.02, 95% CI 0.44 to 2.37) when compared to placebo. Furthermore, when the level of amputation was considered, the incidence of pulmonary embolism was similar between the two treatment groups: above knee amputation (OR 0.79, 95% CI 0.31 to 1.97) and below knee amputation (OR 1.53, 95% CI 0.09 to 26.43). Ten participants died during the study; five underwent a post-mortem and three were found to have had a recent pulmonary embolism, all of whom had been on placebo. Bleeding events were reported in less than 10% of participants in both treatment groups but specific data were not presented. This study did not report the methods used to conceal allocation of treatment and therefore it was unclear if selection bias occurred. However, this study appeared to be free from all other sources of bias. No study looked at mechanical prophylaxis.

AUTHORS' CONCLUSIONS

As only two studies were included in this review, each comparing different interventions, there is insufficient evidence to make any conclusions regarding the most effective thromboprophylaxis regimen in patients undergoing lower limb amputation. Further large-scale studies that are of good quality are required.

Effects of mirtazapine on the sleep wake rhythm of geriatric patients with major depression: an exploratory study with actigraphy

INTRODUCTION

Major depression and insomnia are among the most frequent neuropsychiatric syndromes in the geriatric population. Although most SSRI antidepressants affect sleep continuity, mirtazapine has been found to improve sleep continuity in patients with depression. The aim of the present study was to assess by actigraphic recordings changes in sleep patterns of geriatric patients with major depression before and during treatment with mirtazapine (30 mg).

METHODS

Patients aged 60 years or more with major depressive disorder were recruited at the outpatient service of a specialized mental health centre. Severity of depression was rated with the Montgomery-Asberg depression rating scale and subjective perception of sleep was assessed with the Pittsburgh sleep quality index (PSQI). Actigraphic parameters were registered 4 days before the onset of mirtazapine treatment (patients were drug free in this period of time) and recorded at day 60 of treatment with mirtazapine.

RESULTS

A significant decrease was observed in the sleep fragmentation index. While a significant improvement was observed in the subjective assessment of quality after treatment with mirtazapine, actigraphic measures of sleep parameters did not show changes in line with mirtazapine treatment.

DISCUSSION

Mirtazapine produces minimal changes on actigraphic measures in the sleep of elderly outpatients. Sleep produced by mirtazapine indicates a more pronounced effect in ≥ 80-year-old patients. This differential response should be considered during treatment of this clinical population.

Physical and radiographic identification of the bones of the wrist by junior doctors

Accurate clinical and radiographic examination of a wrist is required to diagnose injury. Knowledge of basic wrist anatomy is the key to ensuring a complete assessment. We tested junior doctors' basic knowledge of the bony anatomy of the wrist. We asked 102 trainees in accident and emergency and orthopaedic departments to palpate nine landmarks on uninjured subjects and then asked them to name the carpal bones on a plain wrist radiograph. No doctor identified all nine landmarks clinically. Only 60% could accurately name all eight carpal bones on a plain radiograph. This study highlights a lack of basic anatomical and radiographic knowledge that is required for examination of the wrist in the hospital setting and discusses issues that may relate to this in medical training.

The association between clubfoot and developmental dysplasia of the hip

The association between idiopathic congenital talipes equinovarus (CTEV) and developmental dysplasia of the hip is uncertain. We present an observational cohort study spanning 6.5 years of selective ultrasound screening of hips in clubfoot. From 119 babies with CTEV there were nine cases of hip dysplasia, in seven individuals. This suggests that 1 in 17 babies with CTEV will have underlying hip dysplasia. This study supports selective ultrasound screening of hips in infants with CTEV.

[Radiation protection of patients in interventional radiology]

The purpose of this article is to provide radiologists with key elements of radiation protection for interventional radiology patients. The following points will be discussed: standards of the fluoroscopy units, dedicated dosimetry, risks (especially cutaneous) and means to reduce them, optimization of interventional radiology dose protocols, and national and international regulations. Appropriateness criteria in interventional radiology are national guidelines that should be implemented.

Contrast ultrasonography: necessity of linear data processing for the quantification of tumor vascularization

PURPOSE

This study is intended to compare the value of uncompressed ultrasonic data, obtained after linear power detection of the ultrasonic radiofrequencies that we call linear data, with usual compressed video data for the quantification of tumor perfusion, particularly for monitoring antivascular therapy.

MATERIALS AND METHODS

To form a clinically useful ultrasonic image, the detected power of the received signals (linear data) is compressed in a quasi-logarithmic fashion in order to match the limited dynamic range of the video monitor. The resulting reduced range of signals from an injected contrast agent may limit the sensitivity to changes in the time-intensity curves. Following a theoretical evaluation of the effects of compression on time-intensity curves and as an in vivo example, we measured at different times the effects of an antivascular drug administered to mice bearing melanoma tumors. The mean time-intensity curves within the tumors after bolus injection of a contrast agent were determined using both linear and video data. Linearized data was recovered using the inverse of the true scanner's compression law, which was experimentally determined. Three features were extracted from the time-intensity curves: peak intensity (PI), time to peak intensity (TPI) and area under the curve in the wash-in phase (AUC (wash-in)). When contrast reached its maximum value, the coefficient of variation reflecting the heterogeneity of the intensity of contrast uptake within the tumor, was computed using both data sets.

RESULTS

TPI was found to be similar with either data set (r = 0.98, p < 0.05, factor of 1.09). Linear PI and AUC (wash-in) had significantly earlier decreases after drug administration than video data (p = 0.015 and p = 0.03, respectively). The coefficient of variation was significantly lower when using video rather than linear data (p < 10 (-4)).

CONCLUSION

In conclusion, the use of linear data is the only mathematically valid methodology for determining a tumor's time-intensity curve and, in practice, it allows earlier demonstration of responses to antivascular drugs.

The importance of school and social activities in the transmission of influenza A(H1N1)v: England, April - June 2009

During the containment phase in the United Kingdom (April to June 2009), a cluster of influenza A(H1N1)v cases was identified prompting further investigation and public health action by the Health Protection Agency. The first confirmed case, a pupil at a school in England, was imported. During the following two weeks, 16 further cases were confirmed with epidemiological links to the first imported case. In this cluster, we found that significant transmission occurred in two classes with attack rates of 17.4% and 7.4%. In each of the two classes a case had attended school whilst symptomatic. Other settings included a choir and a party. Minimum and maximum attack rates were 3.6% and 4.2% for the choir and 14.3% and 25% for the party. We did not find any evidence of transmission on two school bus trips despite exposure over 50 minutes to a symptomatic case and over two periods of 30 minutes to a case during the prodromal phase (i.e. within 12 hours of symptom onset). Nor was there onward transmission in another school despite exposure over several hours to two cases, both of whom attended school during the prodromal phase.

Oseltamivir adherence and side effects among children in three London schools affected by influenza A(H1N1)v, May 2009 – an internet-based cross-sectional survey

This report describes the results of a cross-sectional anonymised online survey on adherence to, and side effects from oseltamivir when offered for prophylaxis, among pupils from one primary and two secondary schools with confirmed cases of influenza A(H1N1)v in London in April-May 2009. Of 103 respondents (response rate 40%), 95 were estimated to have been offered oseltamivir for prophylaxis, of whom 85 (89%) actually took any. Less than half (48%) of primary schoolchildren completed a full course, compared to three-quarters (76%) of secondary schoolchildren. More than half (53%) of all schoolchildren taking prophylactic oseltamivir reported one or more side effects. Gastrointestinal symptoms were reported by 40% of children and 18% reported a mild neuropsychiatric side effect. The results confirmed anecdotal evidence of poor adherence, provided timely information with which to assist decision-making, and formed part of the body of growing evidence that contributed to policy changes to restrict widespread use of prophylaxis for school contacts of confirmed cases of influenza A(H1N1)v.

Novel FOXG1 mutations associated with the congenital variant of Rett syndrome

BACKGROUND

Rett syndrome is a severe neurodevelopmental disorder representing one of the most common genetic causes of mental retardation in girls. The classic form is caused by MECP2 mutations. In two patients affected by the congenital variant of Rett we have recently identified mutations in the FOXG1 gene encoding a brain specific transcriptional repressor, essential for early development of the telencephalon.

METHODS

60 MECP2/CDKL5 mutation negative European Rett patients (classic and variants), 43 patients with encephalopathy with early onset seizures, and four atypical Rett patients were analysed for mutations in FOXG1.

RESULTS AND CONCLUSIONS

Mutations have been identified in four patients, independently classified as congenital Rett variants from France, Spain and Latvia. Clinical data have been compared with the two previously reported patients with mutations in FOXG1. In all cases hypotonia, irresponsiveness and irritability were present in the neonatal period. At birth, head circumference was normal while a deceleration of growth was recognised soon afterwards, leading to severe microcephaly. Motor development was severely impaired and voluntary hand use was absent. In contrast with classic Rett, patients showed poor eye contact. Typical stereotypic hand movements with hand washing and hand mouthing activities were present continuously. Some patients showed abnormal movements of the tongue and jerky movements of the limbs. Brain magnetic resonance imaging showed corpus callosum hypoplasia in most cases, while epilepsy was a variable sign. Scoliosis was present and severe in the older patients. Neurovegetative symptoms typical of Rett were frequently present.

Functional imaging using DCE-US: Which parameter for the early evaluation of antiangiogenetic therapies?

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Background: The early evaluation of anti-angiogenic treatments is a challenge in oncology. Functional imaging methods based on the measure of tumoral vascularization have been developed using different modalities (CT, MRI, US). We analyzed the response in four studies using different targeted treatments with dynamic contrast enhanced-ultrasonography (DCE-US). Seven parameters characterizing tumoral perfusion were estimated. The objective of the study was to determine which parameter is the most appropriate to confirm earlier the efficacy of treatments. Methods: A total of 823 DCE-US were performed in 117 patients included in 4 following studies (multikinase inhibitor targeting angiogenic-receptor with a cytotoxic or thyrosine-kinase inhibitor targeted angiogenic-receptor and C-kit or monoclonal antibody anti-VEGFR). Each DCE-US was performed using contrast agent (Sonovue, Bracco) with perfusion and quantification softwares (Toshiba) from raw linear data with a high temporal resolution: 4 frames per second during 3 minutes. Seven quantitative parameters of perfusion were estimated: peak intensity (PI) and area under the total curve (AUC), area under the wash-in (AUWI), area under the wash-out (AUWO), time to peak intensity, mean transit time (MTT), wash-in slope. DCE-US were performed before treatment and after D3, D 8, 15, 21 (according each study design) and every 2 months. Patients were classified in good responders and bad responders according the response (RECIST on CT-scan) after 2 cycles or 2 months. Results: Among the 7 parameters, 2 parameters related to the blood volume studies (AUC and AUWO) were always earlier significantly modified (p = 0.04 to p = 0.004). One was never modified: MTT. For the 4 others, it's depending of each study. Conclusions: DCE-US appears as a sensitive tool to evaluate tumoral response to anti-angiogenic drugs. Functional parameters related to the blood volume are more pertinent and represent a key add value to early evaluation of these therapies studies.

No significant financial relationships to disclose.

Interest of DCE-US with quantification to demonstrate the VDA effect on vascularization in patients with advanced solid tumors treated with AVE8062

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Background: To determine the optimal time for the assessment of the perfusion in patients receiving AVE8062 (Vascular Disrupting Agent) at different doses combined with a fixed dose of cisplatin and then to correlate these results with the tumor response. Methods: Patients (pts) with advanced solid tumors, treated with AVE8062 (from 11.5 to 30 mg/m2) in combination with 75 mg/m2 cisplatin given every 3 weeks, were prospectively followed by DCE-US. DCE-US was performed before treatment, at 3 time points (0, 6 and 24 hours (h)) on Day 1 of the first (C1) and second cycle (C2), then every 2 cycles thereafter. Contrast uptake was acquired using VRI perfusion software after SonoVue bolus injection. Time-Intensity Curves (TIC) were determined using linear raw- data from CHI-Q (Toshiba) software. Peak Intensity (PI) representing the blood volume was calculated from automatic modeling of TIC. CT-scans performed before treatment and every 2 cycles were reviewed and tumor response assessed (RECIST). Results: A total of 96 DCE-US were performed in 13 pts, 11 of whom had data for both cycle 1 and cycle 2. Among these 11 patients, 8 presented with a dramatic decrease of PI and 3 with an increase of PI. At cycle 1, mean change from baseline in PI was -36% at 6h and -47% at 24h after AVE8062 infusion. Greater decreases were observed at cycle 2, -70% at 6 h and 78% at 24 h. No pt had a clinical response, but by cycle 2, the 8 pts with a decrease in PI at 24h went on to have stable disease as best response; 3 pts with increased PI 24h after their second treatment all had disease progression as best response. Conclusions: The best timing to observe the effect of AVE8062 on the PI seems to be 24 hours after drug administration at cycle 2. These preliminary results suggest that 24 hr PI at cycle 2 could be useful for determining pts who are more likely to have disease progression as best response to AVE8062. If confirmed, the assessment of PI variation may predict the clinical response to AVE8062. Further studies are needed to assess the possible predictive value of DCE-US on duration of progression-free survival.

No significant financial relationships to disclose.

[Evaluation of early response to antiangiogenic treatment with dynamic contrast enhanced ultrasound]

Early functional imaging evaluation of targeted treatments in oncology is of major importance. Dynamic contrast enhanced US is now recognized as a functional imaging technique able to evaluate new antiangiogenic drugs targeting superficial and deep seated lesions. This evaluation is based on an analysis of the curve of signal intensity over time after injection of the contrast agent. The availability of quantification software allows objective quantification of tumor perfusion parameters from linear raw data, prior to logarithmic signal compression, including maximum intensity of enhancement, mean transit time, time to peak, and wash-in slope coefficient. Dynamic contrast enhanced US, a sensitive, reproducible and readily available technique, allows early prediction of tumor response to treatment based on changes in vascularity, before morphological changes (RECIST) become apparent.

Functional imaging by DCE-US as a surrogate for response in phase I/II of different targeted therapies by DCE-US: Which quantitative parameter and which timing

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Background: The early evaluation of targeted treatments is a major challenge in oncology. Functional approaches based on the measure of tumoral vascularization have been developed using different modalities of imaging (CT, MRI, US). We analyzed the response of tumors in three studies using different targeted treatments with dynamic contrast enhanced-ultrasonography (DCE-US). Seven parameters characterizing tumor perfusion were estimated. The objective of the study was to determine which parameter is the most appropriate and when to use it to confirm earlier the efficacy of treatment. Methods: A total of 157 DCE-US were performed in 30 responding patients (PFS>3 months) selected from 3 following studies (multikinase inhibitor targeting angiogenic-receptor with a cytotoxic, thyrosine-kinase inhibitor targeted angiogenic-receptor and C-kit, VEGF monoclonal antibody). Each DCE-US was performed using contrast agent (Sonovue,Bracco) with perfusion and quantification softwares (Toshiba) from raw linear data. Seven quantitative parameters of perfusion were estimated: peak intensity (PI) and area under the curve (AUC), area under the wash-in (AUWI), area under the wash-out (AUWO), time to PI, mean transit time (MTT), wash-in slope. DCE-US were performed before treatment and after during 5 periods (P) : 1–12 days(P1), 13–22 days(P2), 23–43 days(P3), 44–110 days (P4), > 111 days(P5). Results: 1099 parameters have benefited a statistical analysis. Significant modifications (P<0.05) of 4 parameters (PI, AUC, AUWI, AUWO) were observed for the 3 treatments. The earliest significant modifications were observed during the 3rd period for the first 2 studies and during the 4th period for the 3rd study. Conclusions: DCE-US is a sensitive tool to evaluate early tumor response to targeted drugs. Four functional parameters were significantly modified patients responding to treatment: PI, AUC, AUWI, AUWO. Those modifications appear earlier for the multikinase inhibitor targeting angiogenic receptor and the thyrosine-kinase inhibitor targeted angiogenic receptor and C-kit ( (23–43 d) compared to VEGF monoclonal antibody (44 -110 d). DCE- US represent a key add value to early evaluation of targeted therapies.

No significant financial relationships to disclose.