Distinct perceptive pathways selected with tonic and bursting patterns of thalamic stimulation

BackgroundNovel patterns of electrical stimulation of the brain and spinal cord hold tremendous promise to improve neuromodulation therapies for diverse disorders, including tremor and pain. To date, there are limited numbers of experimental studies in human subjects to help explain how stimulation patterns impact the clinical response, especially with deep brain stimulation.We propose using novel stimulation patterns during electrical stimulation of somatosensory thalamus in awake deep brain stimulation surgeries and hypothesize that stimulation patterns will influence the sensory percept without moving the electrode.MethodsIn this study of 15 fully awake patients, the threshold of perception as well as perceptual characteristics were compared for tonic (trains of regularly-repeated pulses) and bursting stimulation patterns.ResultsIn a majority of subjects, tonic and burst percepts were located in separate, non-overlapping body regions (i.e., face vs. hand) without moving the stimulating electrode (p < 0.001; binomial test). The qualitative features of burst percepts also differed from those of tonic-evoked percepts as burst patterns were less likely to evoke percepts described as tingling (p = 0.013; Fisher’s exact test).ConclusionsBecause somatosensory thalamus is somatotopically organized, percept location can be related to anatomic thalamocortical pathways. Thus, stimulation pattern may provide a mechanism to select for different thalamocortical pathways. This added control could lead to improvements in neuromodulation - such as improved efficacy and side effect attenuation - and may also improve localization for sensory prostheses.     

Oral Everolimus for Treatment of a Giant Left Ventricular Rhabdomyoma in a Neonate—Rapid Tumor Regression Documented by Real Time 3D Echocardiography

The presented case reports on successful treatment with everolimus in a neonate with left ventricular giant rhabdomyoma. The authors used a different dosage regime compared to literature and documented rapid tumor regression by 3D echocardiography.     

MRI accurately identifies early murine mammary cancers and reliably differentiates between in situ and invasive cancer: correlation of MRI with histology

MRI methods that accurately identify various stages of mouse mammary cancer could provide new knowledge that may have a direct impact on the management of breast cancer in patients. This research investigates whether we can accurately follow the progression from in situ to invasive cancer by the evaluation of in vivo and ex vivo MRI, and in comparison with histology as the gold standard for the diagnosis and staging of cancer. Six C3(1)SV40Tag virgin female mice, aged 12–16 weeks, were studied. At this age, these mice develop in situ cancer that resembles human ductal carcinoma in situ (DCIS). Fast spin‐echo images of inguinal mammary glands were acquired at 9.4 T. After in vivo MRI, mice were sacrificed; inguinal mammary glands were excised and fixed in formalin for ex vivo MRI. Three‐dimensional, volume‐rendered, in vivo and ex vivo MR images were then correlated with histology. High‐resolution ex vivo scans facilitated the comparison of in vivo scans with histology. The sizes of mammary cancers classified as in situ on the basis of histology ranged from 150 to 400 µm in largest diameter, and the average signal intensity relative to muscle was 1.40 ± 0.18 on T₂‐weighted images. Cancers classified as invasive on the basis of histology were >400 µm in largest diameter, and the average intensity relative to muscle on T₂‐weighted images was 2.34 ± 0.26. Using a cut‐off of 400 µm in largest diameter to distinguish between in situ and invasive cancers, a T₂‐weighted signal intensity of at least 1.4 times that of muscle for in situ cancer, and at least 2.3 times that of muscle for invasive cancer, 96% of in situ and 100% of invasive cancers were correctly identified on in vivo MRI, using histology as the gold standard. Precise MRI–histology correlation demonstrates that MRI reliably detects early in situ cancer and differentiates in situ from invasive cancers in the SV40Tag mouse model of human breast cancer. Copyright © 2015 John Wiley & Sons, Ltd.     

Rubella Virus-associated Anterior Uveitis in a Vaccinated Patient: A Case Report

Rubella virus is involved in the pathogenesis of Fuchs heterochromic uveitis and almost all cases in Europe show an active antibody production in the aqueous humor against rubella virus. Herein we report a case of a fully vaccinated patient with common variable immunodeficiency who developed unilateral Fuchs heterochromic uveitis secondary to rubella virus which was proven by intraocular fluid examination. Awareness of rubella associated anterior uveitis should remain also in vaccinated patients, especially those without a fully competent immune system.     

椎弓根螺钉三椎体内固定对脊椎爆裂性骨折患者椎体与神经功能状态的影响观察

目的:探讨椎弓根螺钉三椎体内固定对脊椎爆裂性骨折患者椎体与神经功能状态的影响.方法:选取2013年7月至2015年1月于本院进行治疗的58例脊椎爆裂性骨折患者为研究对象,对其进行回顾性研究,将其根据手术方式不同分为对照组(短节段椎弓根内固定组)29例和观察组(椎弓根螺钉三椎体内固定组)29例,然后将两组患者手术前与手术后不同时间的伤椎恢复指标与血清神经功能相关指标进行比较.结果:观察组手术后不同时间的伤椎恢复指标中的后凸Cobb角、椎体平移率、椎体高度丢失率与血清神经功能相关指标中的BDNF、NSE、NGF及S100B均显著好于同期的对照组指标,并且明显好于其治疗前,均有显著性差异(P＜0.05).结论:椎弓根螺钉三椎体内固定可更为有效地恢复脊椎爆裂性骨折患者椎体参数,并且更有助于神经功能状态的恢复.     

Cranio-caudal approach to hepatic veins in laparoscopic central bisectionectomy (with Video)

BackgroundLaparoscopic central bisectionectomy (Couinaud's segment IV, V, and VIII) needs exposure of the RHV and MHV on the surface of the remnant and the resecting side, respectively. Avoiding venous injury is mandatory and laparoscopy-specific cranio-caudal approach to hepatic veins might be helpful [1]. We present this procedure in performing laparoscopic central bisectionectomy.PatientA 45-year-old female was admitted to our hospital with a 6 cm HCC in the segment VIII and IV. Her comorbid disease was non-cirrhotic HBV hepatitis (Child-Pugh grade A) and diabetes (untreated).MethodAfter cholecystectomy, G₄ branches were dissected and cut by extra- or intra-hepatic approach. Hilar plate was dissected and the G_ant was encircled and occluded by a vascular clip. Afterwards, exposure of the MHV was started at its root on IVC [2,3] and extended in cranio-caudal direction [1]. After sufficient space was obtained around the G_ant, the G_ant and the MHV were cut. Parenchymal transection between right anterior and right posterior sections was also started form the root of the RHV to its cranio-caudal direction. Liver resection was finished with full exposure of the RHV.ResultsThe operating time was 380 minutes, and the blood loss volume was 30 ml. Postoperative CT image showed exposure of the RHV and umbilical portion of Glissonean branch, and no fluid retention.ConclusionLaparoscopy-specific cranio-caudal approach to hepatic veins may be useful to avoid split injury of venous branches [4], especially if the hepatectomy requires complete exposure of hepatic vein, such as central bisectionectomy.     

Clinical and radiological outcome after minimally invasive surgical approach for type II unstable odontoid fractures

IntroductionAnterior odontoid screw fixation is a valid surgical option for unstable odontoid fractures, as type II Anderson D’Alonzo fractures. Grauer further divided type II fractures in subtypes according to the fracture line, providing recommendations for implementation of screw fixation techniques.ObjectivePrimary endpoint of our study is to evaluate the postoperative results of minimally invasive odontoid screw insertion in terms of outcome, fusion rate and stability of cranio-cervical junction. Secondary endpoint was to investigate the influence of age or fractures’ features on outcome and fusion rate.Materials and methodsWe report the clinical and radiological features of 32 patients harbouring unstable type II fractures operated by a minimally invasive odontoid screw insertion technique. All patients underwent a high resolution multiplanar CT in order to assess fracture features according to Grauer's classification; the integrity of ligaments was investigated by MRI. In addition, a preoperative neurological performance (modified Rankin Scale, mRS) was evaluated for patients either directly or interviewing their families. Follow-up at one, three and six months and 1 year have been performed (averaging 13.5 months) by cervical CT (fusion rate and stability) and mRS update. In order to investigate the influence of age on postoperative neurological performance, two groups (≤ 50 yrs, 9 pts/ > 50 yrs, 23 pts) were separately considered and analysed. Overall, we observed no surgery related complications. We also analysed the fusion rate and its correlation with patient age and Grauer's subtype of fracture.ResultsAt last available clinical follow-up, the preoperative performance was preserved (mRS 0/1: 24, 75%; mRS 2–4: 9, 15%) although with slight reduction of intact patients (mRS 0: 22 vs. 19; 71.8 vs. 59.3%). Younger patients (≤ 50 yrs) fared significantly better than older ones, achieving a good clinical outcome (mRS 0/1) in 100% vs. 69.5% (9/9 vs. 16/23 pts). Statistical analysis showed a fair correlation between age and outcome. Other factors such as sex and Grauer's type did not influence significantly the clinical outcome. Nine patients did not complete a full radiological follow-up and were therefore excluded from analysis of radiological outcome. Among the remaining 23 patients, only 25% of those who were followed three months or less showed fusion; conversely, all patients who have been examined from 6 to 48 months fused. Among the non-union patients, two underwent a second surgery by posterior approach.ConclusionsIn our recent experience, the minimally invasive AOSF proved safe and effective in treating odontoid peg fractures. Selection based on Grauer's type is mandatory to achieve best results. While in the elderly, an anterior approach is well accepted as the first choice treatment, we recommend that this option should be offered as a suitable alternative to Halo or orthosis also in younger patients since it provides prompt, excellent clinical outcome and high fusion rate especially in this age group.     

Allograft use in anterior cruciate ligament reconstruction surgery: a review of the current literature

Anterior cruciate ligament reconstruction (ACLR) surgery plays an important role in restoring stability and function to the knee joint following ACL rupture. Owing to an increase in activity levels and sports participation, ACLR has become one of the most commonly performed procedures world-wide. Graft choice may influence clinical outcomes, and therefore the optimal graft remains widely debated. Whilst, historically, autograft tissue has been the preferred choice, the past decade has seen a steady increase in the popularity of allografts. This demand is partly driven by improvements in graft availability, procurement processes and safety; but more importantly a desire to eliminate issues related to donor site morbidity from graft harvest. Despite this, there remains controversy surrounding the use of allograft in ACLR surgery, with much of the literature demonstrating conflicting evidence on functional and survivorship outcomes. In this article we review the current literature surrounding allograft use in ACLR, from the biology of allograft integration, through to outcomes in clinical practice.