Buried Bumper Syndrome: A common complication of levodopa intestinal infusion for Parkinson disease

BackgroundPercutaneous endoscopic gastrostomy (PEG) is required for Levodopa/Carbidopa Intestinal Gel (LCIG) delivery in patients with advanced Parkinson's disease (PD) as well as for enteral feeding in a variety of neurological disorders. Buried Bumper Syndrome (BBS) is a serious complication of PEG. The frequency of BBS in patients receiving LCIG treatment has never been reported.ObjectivesTo compare the frequency of BBS in patients on LCIG treatment or on enteral feeding over the past 12 years and identify possible risk factors.MethodsWe reviewed prospectively recorded data from 2009 to 2020 on two case-series: LCIG-treated PD patients and non-PD patients on enteral nutrition. We identified all BBS incidences. Patients’ characteristics, clinical manifestations, BBS management, possible risk factors and outcomes were analyzed.ResultsDuring the 12 years, 35 PD patients underwent PEG insertion for LCIG infusion, and 123 non-PD patients for nutritional support. There were eight cases of BBS in six PD patients (17.1%). Six of them were effectively managed without treatment discontinuation. Of the enteral feeding patients, only one developed BBS (0.8%) (p < 0.001). We identified inappropriate PEG site aftercare, weight gain, early onset PD, longer survival, treatment duration, dementia and PEG system design as potential risk factors for BBS development.ConclusionsBBS occurs more frequently in LCIG patients than in patients receiving enteral feeding. If detected early, it can be successfully managed, and serious sequalae or treatment discontinuation can be avoided. Regular endoscopic follow-up visits of LCIG-treated patients and increased awareness in patients and clinicians are recommended.     

Cancellous Bone Structure in the Growing and Aging Lumbar Spine in a Historic Nubian Population

There is abundant data on cancellous bone in the aging human spine, but little relating to the growing vertebral cancellous bone in childhood and adolescence. The purpose of this study was to map vertebral cancellous bone in a growth and age series of historic skeletal samples and to make comparisons with data published on recent material. Lumbar vertebral bodies were collected from 65 skeletons (0–60 years) from a medieval Nubian population. Ethnohistoric information was collected to interpret conditions that might have influenced bone structure and metabolism. The cancellous bone was studied three dimensionally, using stereophotography and scanning electron microscopy and morphometrically by performing a semiautomatic structural analysis on digitized backscattered electron images of polymethacrylate-embedded material. The cancellous bone structure in the children consisted mainly of a densely packed, uniform network of small rodlike trabeculae. The greatest bone volume fraction with small, more platelike trabeculae was observed during adolescence. In young adults, larger platelike trabeculae were present in the central zone and smaller trabeculae in the superior and inferior zones, as described for modern skeletal material. Structural changes associated with aging were observed much sooner than in modern man. By the estimated age of approximately 50–60 years, the predominant architectural elements were slender rarified rods in both sexes. The ethnohistorical data suggest that this was essentially a black African population of physically active peasants, not likely to suffer Vitamin D insufficiency or deficient calcium intake. Thus an earlier onset of the biological age changes in cancellous bone found in modern populations was probably prevalent. Received: 1 March 1996 / Accepted: 31 December 1996     

Interpretation of functional series expansions

While much research has been devoted to the implementation and application of Volterra and Wiener functional series expansions in the identification and characterization of biological systems, little effort has been focused on the fundamental problem of interpreting the resulting kernels. This paper describes the application of the series to the components of a known model of the human pupil control system. As more complicated elements are put together, insight into kernel interpretation is built up incrementally until the total system is identified. Practical limitations and methods are also discussed.     

Restricted field of view magnetic resonance imaging of a dynamic time series.

A restricted field of view (rFOV) approach for imaging a dynamic time series of volumes of limited spatial extent within a larger subject is described. The shorter readout with rFOV-MRI can be exploited to either limit image artifacts or increase spatial resolution. To accomplish rFOV imaging of a multislice volume for a dynamic series, an outer volume suppression (OVS) preparation that saturates signal external to a cylinder through the subject is followed by slice-selective excitation and a spiral readout. The pass- and stopband efficiencies of the OVS in an agar gel phantom were 97% (+/-1.5%) and 3% (+/-1%), respectively. Profiles of the temporal signal-to-noise ratio (SNR) were measured in a phantom and an adult brain. The rFOV sequence reduced distortions from off-resonance signal and T2*-induced blurring compared to a conventional sequence. Sequence utility is demonstrated for high-resolution rFOV functional MRI (fMRI) in the visual cortex. The rFOV sequence may prove to be useful for other multislice dynamic and high-resolution imaging applications.     

Spectral analysis of spontaneous contractions of the isolated portal vein of rats

Summary The spontaneous contractions of segments of rat portal veins have been examined in vitro under isotonic and isometric conditions. The power density spectra of recorded time series lasting 10–60 min were calculated. The spectra usually consist of harmonic frequency components. Only during shorter periods of analysis (10 min time series) we sometimes found additional non-harmonic components. All frequency components are proportionally shifted by changes of the bath temperature according to an average Q₁₀ of 2.0. Increase of the load decreases the frequency of the contractions.The results of the spectral analysis, indicating a preponderance of a single source of periodicity, were supported by direct evidence of a pacemaker region. By recording contractions after systematic dissections of the portal vein segment, we found that spontaneous activity is generated at the central end of the segment.This work was supported by the Austrian Research Fund     

改进的小波域医学图像序列的运动估计

医学图像序列压缩是远程医疗系统中的重要技术，而运动估计在视频序列压缩中起着关键作用。我们提出了一种改进的正方形-菱形搜索算法来实现医学图像序列的运动估计。这种改进的正方形-菱形算法减少了搜索点数。我们将其应用于小波域的医学图像序列的运动估计，并对数字减影血管造影图像序列（DSA）进行实验。结果表明，改进后的小波域正方形-菱形算法较其他算法精度高。     

Individual differences in the perception of optimism and disease severity: A study among individuals with Parkinson's disease

The extent to which individuals with Parkinson's disease (PD) show lability in optimism was explored in the present study. The relationship between optimism and perceived disease severity was examined as well. Twelve individuals diagnosed with PD completed self-report measures for 70 consecutive days. All individuals in this study showed lability in optimism over short time periods; however, 67% of the sample showed no pervasive negative changes in optimism over time. Increased levels of optimism on one day were predictive of decreased perceived disease severity the next day for one-fourth of the sample, after controlling for negative affect. Individual differences in the relationship between optimism and disease severity provided support for the idea that living with chronic illness has no monolithic meaning. More optimistic individuals reported less need for assistance with basic functional abilities than less optimistic individuals. The usefulness of lability in optimism among individuals with PD is discussed.     

Description of Heart-Rate Variability Data in Accordance With a Physiological Model for the Genesis of Heartbeats

A survey is presented of techniques which transform heart-rate variability data into a signal that is both visually informative and accessible for analysis. The Instantaneous Heart-Rate (IHR) signal is introduced, i.e. the signal having the value of the heart rate (inverse interbeat interval) during the interval concerned. The IHR signal differs from the standard Delayed Heart-Rate (DHR) signal, which is always one beat late. The relationship is discussed between the different representation methods and the Integral Pulse Frequency Modulation (IPFM) model, the latter being a physiologically plausible model for the transformation of a continuous input signal (e.g., nervous influence on the cardiac pacemaker) into a series of events (heartbeats). It is shown that when the IHR signal is used as input of the IPFM model, the event series from which the signal was derived appears at the output. Hence, if the IPFM model is accepted as a model of the pacemaker, the IHR signal may be considered as an approximation of the neural (sympathetic and parasympathetic) influence on the pacemaker. In addition we show that the appearance of the IHR signal is less affected by trigger errors or extrasystoles than the standard DHR signal. It is concluded that the most attractive time-domain representation of physiological event series consists of the IHR signal, because this signal, being conceptually and computationally simple, is consistent with the IPFM model.     

局限性癫痫脑电时间序列的分形维数计算比较

为探索应用非线性动力学理论诊断癫痫病的新方法，对局限性癫痫病患者脑电时间序列进行了相关维数（Ｄｃ）和波形维数（Ｄｗ）的计算比较。观察到，痫性导联脑电的分形维数多低于对侧导联的值；相关维数Ｄｃ的相对变化量较波形维数Ｄｗ大；而波形维数Ｄｗ对痫性棘波敏感；结果提示，脑电时间序列的分形维数有可能成为诊断癫痫的特征参数，值得进一步深入研究。     

Extrapelvic colon--areas of failure in a reoperation series: implications for adjuvant therapy

A total of 230 patients had planned single or multiple reoperative procedures following "curative" resection of colorectal cancer at the University of Minnesota. The site of the primary lesion was extrapelvic in 91, and later evidence of cancer was found in 58 patients (64%) at re-operation and/or other follow-up. Eight of the 58 (14%) were converted to disease-free status. Incidence and patterns of failure were correlated with initial operative-pathologic extent of disease (87 of the 91 at risk had initial tumor extension beyond the bowel wall, involved nodes or both) and comparisons were made with the previously analyzed rectal reoperation patients. While a component of local-regional failure was more common with rectal lesions (48/74 at risk, 65%), it was not uncommon with extrapelvic primaries (44/91-48%). The incidence of hematogenous metastasis (DM) was equal, but the pattern of initial DM differed (extrapelvic colon--primarily liver; rectum--liver and lung). Peritoneal seeding was a more common component of failure with the extrapelvic primaries (19/91--21% vs 3/74-4%). Since surgery alone is inadequate treatment for many patients with colon as well as rectal cancer, the rationale of adjuvant radiation and systemic therapy, alone or in combination, is discussed.