Amygdalohippocampectomy for epilepsy in a patient with prior ipsilateral deep brain stimulator lead placement

In light of failed medical therapy for movement disorders, the use of deep brain stimulation (DBS) has increased the last two decades. Many complications may transpire; however, to our knowledge, the literature does not mention the phenomena of brain shift from a second unrelated neurosurgical procedure and its theoretical effect on lead displacement and lead function. We present a patient with a left sided DBS for essential tremor and subsequent left amygdalohippocampectomy for temporal lobe epilepsy with minimal radiographic distortion of the DBS lead and without clinical or functional complications. A 47-year-old woman presented with bitemporal epilepsy secondary to a brain injury acquired in childhood in addition to a comorbid bilateral essential tremor, both refractory to medical intervention. A successful left-sided DBS placement was performed with satisfactory resolution of her essential tremor. The patient subsequently developed deterioration of seizure control, becoming refractory to anti-epileptic medications, requiring surgical intervention. A left-sided selective amygdalohippocampectomy and techniques to minimize brain shift were performed without complications. Postoperative imaging suggested minimal distortion of the DBS lead. This did not correspond with reemergence of her essential tremor, implying that the lead maintained functional utility. Brain shift secondary to a craniotomy may cause DBS lead displacement. This phenomenon should be considered when planning operative approaches and can be limited by selective resections. With the growing propensity for placement of DBS leads and the risk of lead displacement, it is important to consider operative approaches to minimize brain shift.     

中文版患者床边交班感知量表的信效度研究

目的翻译患者床边交班感知量表（PVNC-BR）,并初步评价其信度与效度。方法严格遵循翻译-回译-专家咨询步骤对量表进行跨文化调试,并通过对138例患者进行调查,检测中文版PVNC-BR的信效度。结果探索性因子分析共提取3个公因子,17个条目,累积贡献率为61．043％,各因子的负荷数为0．413～0．861;Cronbach’sα系数为0．821,各因子的Cronbach’sα系数为0．696～0．854;重测信度为0．879,各因子的重测信度为0．771～0．922。结论中文版PVNC—BR量表具有较好的信度、效度,符合心理学测量要求,可用于测评实施床边交班患者的感知评价。     

双因素理论在护士夜班管理中的应用

目的 探讨双因素理论在血液净化中心护士夜班管理中的作用。方法 调查血液净化中心37位护理人员的职称、学历、年龄、工龄、工作能力及科研水平等状况，综合考虑后制定新的管理制度应用于护士夜班管理中，观察新制度实施前后成效。结果 新的夜班管理制度实施以来，全区护士的满意度、学习热情、继续教育、竞争意识、服务意识、工作态度、管理水平及科研水平等较前差异有统计学意义（P〈0．05）。结论 科学、合理的夜班护理管理制度，并结全适当的激励制度有利于实现护理管理目标。     

耳鼻咽喉科交接班制度的改进与效果

目的提高交接班质量，减少交接班过程中的不安全因素。方法针对交接班过程中存在的问题，修订交接班制度，细化交接班内容，改进流程与方法，加强交接班工作的监督。结果改进交接班制度后，加强了环节质量控制，提高了护理工作的质量和效能，患者满意度、接班护士满意度显著提高，护理缺陷隐患发生率明显下降。结论规范交接班制度，提高交接班质量，是确保护理安全的重要环节。     

Attention modulates step initiation postural adjustments in Parkinson freezers

BackgroundIn view of freezing of gait's circumstances of occurrence in Parkinson's disease, attentional resources appear to be involved in step initiation failure. Anticipatory postural adjustments (APAs) are essential because they allow unloading of the stepping leg and so create the conditions required for progression.Our main objective was to establish whether or not a change in attentional load during step initiation modulates APAs differently in patients with vs. without freezing of gait.MethodsThree groups of 15 subjects were recruited: elderly people and parkinsonian patients with or without freezing of gait. Attention was modulated before step execution by means of an auditory oddball discrimination task with event-related potential recording. The primary endpoint was the occurrence of inappropriate APAs following the attentional task, i.e. APAs not followed by a step after an intercurrent auditory stimulus.ResultsIn parkinsonian patients with freezing of gait, inappropriate APAs were recorded in 63% of the trials and were observed more frequently than in patients without freezing of gait (51%) and elderly controls (48%). Furthermore, inappropriate APAs in freezers were longer and more ample than in parkinsonian non-freezers and controls. Lastly, postural preparation was impaired in the parkinsonian patients.ConclusionOur results indicate that allocation of attentional resources during step preparation influences the release of APAs differently in freezers and non-freezers. Modulating attentional load is partly responsible for triggering an inappropriate motor program. This difficulty in focusing attention or resisting interference may contribute (at least in part) to the gait initiation failure observed in parkinsonian freezers.     

Can rotatory knee laxity be predicted in isolated anterior cruciate ligament surgery?

Purpose

Despite the overall success of the surgical anterior cruciate ligament (ACL) reconstruction, some patients still present with instability symptoms even after the surgery, mainly due to the presence of associated lesions. At present, the pivot shift test has been reported to be the benchmark to assess rotatory knee laxity. The purpose of this study was to quantitatively evaluate rotatory knee laxity at time-zero in order to determine whether detected post-reconstruction laxity was predictable by its value measured before the reconstruction, which was hypothized to be influenced by the presence of associated lesions.

Methods

Rotatory knee laxity was retrospectively analysed in 42 patients, including two different ACL reconstructions. The maximal anterior displacement and the absolute value of the posterior acceleration reached during the reduction of the tibial lateral compartment were intra-operatively acquired by using a navigation system and identified as discriminating parameters. For each parameter, statistical linear regression analysis (line slope and intercept) was performed between pre- and post-reconstruction values.

Results

No statistically significant influence of the initial posterior acceleration on the post-reconstruction outcome was found (line slope, p > 0.05), although a statistically significant line intercept was indeed identified (p < 0.001). A statistically significant influence on the surgery outcome was instead found for the initial value of the anterior tibial displacement (line slope = 0.39, p = 0.004), meaning that, on average, about 40 % of the post-reconstruction lateral compartment displacement could be explained by the corresponding pre-reconstruction value. Both of these findings highlighted the importance of intra-operative quantification of rotatory knee laxity to identify correct indications for the surgery.

Conclusions

This study provided important implications for the future possibility of defining a quantifying tool able to assess rotatory knee laxity during ACL reconstruction. This could allow detection of additional injuries to secondary restraints by easily performing rotatory knee laxity tests, which in turn could reduce post-surgical recurrence of knee instability.     

Assessing short and long‐term educational impact of visits to hospice via a combination of qualitative methods

While qualitative methods have gained considerable recognition in medical education research, employing multiple qualitative data sources in assessing long‐term educational impact is rare. Utilising in‐depth data analysis method to six cross‐sectional cohorts (2004–2009) of students’ reflection papers (n = 213), this article demonstrates how students experienced subtle but important shifts in their attitudes (including personal, professional and spiritual domains) after making field visits to a hospice centre as part of the Special Needs Dentistry module. For retrospective assessment of learning retention, a pilot focus group was conducted with three junior faculty members who participated in the field visits to a hospice during their own undergraduate training. A subsequent focus group was conducted with graduates of the 2008 (n = 8) cohort using a refined discussion guide arising from the analysis of pilot group results. Graduates were unanimous in stating that the visits had sown ‘seeds’ in their minds and hearts, seeds which started to grow after they completed dental school and began to practice. This is demonstrative of the long‐term positive educational impact of the pedagogical design that entailed a special site visit coupled with post‐visit debrief and written reflection.     

Realized niche shift during a global biological invasion

Accurate forecasts of biological invasions are crucial for managing invasion risk but are hampered by niche shifts resulting from evolved environmental tolerances (fundamental niche shifts) or the presence of novel biotic and abiotic conditions in the invaded range (realized niche shifts). Distinguishing between these kinds of niche shifts is impossible with traditional, correlative approaches to invasion forecasts, which exclusively consider the realized niche. Here we overcome this challenge by combining a physiologically mechanistic model of the fundamental niche with correlative models based on the realized niche to study the global invasion of the cane toad Rhinella marina. We find strong evidence that the success of R. marina in Australia reflects a shift in the species’ realized niche, as opposed to evolutionary shifts in range-limiting traits. Our results demonstrate that R. marina does not fill its fundamental niche in its native South American range and that areas of niche unfilling coincide with the presence of a closely related species with which R. marina hybridizes. Conversely, in Australia, where coevolved taxa are absent, R. marina largely fills its fundamental niche in areas behind the invasion front. The general approach taken here of contrasting fundamental and realized niche models provides key insights into the role of biotic interactions in shaping range limits and can inform effective management strategies not only for invasive species but also for assisted colonization under climate change.Understanding the factors that limit species’ geographic ranges has long stood as a fundamental goal in ecology (1) and is critical for making robust predictions of species’ range shifts as a result of climate change and biotic exchange. Niche theory (2) argues that species’ ranges are limited by physiological tolerances (which define the fundamental niche), as well as biotic interactions and dispersal barriers (which further constrain the fundamental niche to the realized niche), but the relative roles of these factors in shaping range limits remain poorly understood. Standard approaches to range prediction are based on correlations between species'' observed distributions and climate (i.e., the realized niche) (3, 4), and thus confound the influences of abiotic and biotic constraints on species’ ranges.Range shift projections based on correlative models also assume that species’ niches (both realized and fundamental) are conserved through space and time (3, 5, 6). However, there is growing evidence to suggest that species can undergo rapid niche shifts in novel environments (7–9) through either evolved environmental tolerances (fundamental niche shifts) (10, 11) or release from dispersal barriers or biotic constraints (realized niche shifts) (12, 13). Understanding whether such niche shifts are widespread in nature not only is important for validating the use of correlative models in climate change and invasive species impact assessments but also has implications for understanding patterns of community assembly and speciation (14, 15).Invasive species frequently experience release from biotic interactions and dispersal barriers in their invaded ranges (4, 12, 16), and thus provide model systems for investigating the degree to which niches are spatially and temporally conserved. Current approaches for examining niche shifts in invasive species primarily rely on comparisons of climates occupied by species in their native and invaded ranges (6, 7, 17, 18). However, such correlative comparisons fail to differentiate between the influences of adaptation after introduction and biotic interactions and dispersal barriers that are absent in a species’ invaded range. Here we present an approach that helps resolve this issue by integrating correlative niche models with mechanistic biophysical predictions of the fundamental niche (19). Biophysical models incorporate links between climate and an organism’s functional traits and are developed independent of a species’ current distribution. The biophysical approach thus provides a prediction of where a species can survive and reproduce in the absence of biotic interactions and dispersal limitations (19). We apply this mechanistic approach to investigate whether the invasion of Australia by the cane toad (Rhinella marina, formerly Bufo marinus) has been facilitated by a shift in the species’ realized or fundamental niche. Since its introduction to Australia in 1935 as a biological control agent, R. marina has expanded its range to include more than 1.2 million km² of the continent (20). This large-scale invasion has been facilitated by thermal acclimation (21, 22), as well as evolutionary shifts in locomotor performance (23). Have the environmental tolerances of toads evolved as well?     

Hybrid spectral domain method for attenuation slope estimation

Attenuation estimation methods for medical ultrasound are important because attenuation properties of soft tissue can be used to distinguish between benign and malignant tumors and to detect diffuse disease. The classical spectral shift method and the spectral difference method are the most commonly used methods for the estimation of the attenuation; however, they both have specific limitations. Classical spectral shift approaches for estimating ultrasonic attenuation are more sensitive to local spectral noise artifacts and have difficulty in compensating for diffraction effects because of beam focusing. Spectral difference approaches, on the other hand, fail to accurately estimate attenuation coefficient values at tissue boundaries that also possess variations in the backscatter. In this paper, we propose a hybrid attenuation estimation method that combines the advantages of the spectral difference and spectral shift methods to overcome their specific limitations. The proposed hybrid method initially uses the spectral difference approach to reduce the impact of system-dependent parameters including diffraction effects. The normalized power spectrum that includes variations because of backscatter changes is then filtered using a Gaussian filter centered at the transmit center frequency of the system. A spectral shift method, namely the spectral cross-correlation algorithm is then used to compute spectral shifts from these filtered power spectra to estimate the attenuation coefficient. Ultrasound simulation results demonstrate that the estimation accuracy of the hybrid method is better than the centroid downshift method (spectral shift method), in uniformly attenuating regions. In addition, this method is also stable at boundaries with variations in the backscatter when compared with the reference phantom method (spectral difference method). Experimental results using tissue-mimicking phantom also illustrate that the hybrid method is more robust and provides accurate attenuation estimates in both uniformly attenuating regions and across boundaries with backscatter variations. The proposed hybrid method preserves the advantages of both the spectral shift and spectral difference approaches while eliminating the disadvantages associated with each of these methods, thereby improving the accuracy and robustness of the attenuation estimation.     

Comparison of biliary atresia with and without intracranial hemorrhage

Background/Purpose

Intracranial hemorrhage (ICH) is a severe complication of biliary atresia (BA). We aimed to compare the clinical data of BA patients with and without ICH.