Hemodialysis vascular access options in pediatrics: considerations for patients and practitioners

Recent data indicate that the incidence of end-stage renal disease (ESRD) in pediatric patients (age 0–19 years) has increased over the past two decades. Similarly, the prevalence of ESRD has increased threefold over the same period. Hemodialysis (HD) continues to be the most frequently utilized modality for renal replacement therapy in incident pediatric ESRD patients. The number of children on HD exceeded the sum total of those on peritoneal dialysis and those undergoing pre-emptive renal transplantation. Choosing the best vascular access option for pediatric HD patients remains challenging. Despite a national initiative for fistula first in the adult hemodialysis population, the pediatric nephrology community in the United States of America utilizes central venous catheters as the primary dialysis access for most patients. Vascular access management requires proper advance planning to assure that the best permanent access is placed, seamless communication involving a multidisciplinary team of nephrologists, nurses, surgeons, and interventional radiologists, and ongoing monitoring to ensure a long life of use. It is imperative that practitioners have a long-term vision to decrease morbidity in this unique patient population. This article reviews the various types of pediatric vascular accesses used worldwide and the benefits and disadvantages of these various forms of access

Retinal Coding: Encoding and Decoding in Natural Scenes

Everything that the brain sees must first be encoded by the retina, which maintains a reliable representation of the visual world in many different, complex natural scenes while also adapting to stimulus changes. Decomposing the population code into independent and cell-cell interactions reveals how broad scene structure is encoded in the adapted retinal output. By recording from the same retina while presenting many different natural movies, we see that the population structure, characterized by strong interactions, is consistent across both natural and synthetic stimuli. We show that these interaction contribute to encoding scene identity, and demonstrate that leveraging this underlying interaction network improves scene decoding. This population structure likely arises in part from shared bipolar cell input as well as from gap junctions between retinal ganglion cells and amacrine cells. Separately, we use a task-agnostic deep architecture, and encoder-decoder, to model the retinal encoding process and characterize its representation of `time in the natural scene' in a compressed latent space. In this end-to-end training, an encoder learns a compressed latent representation from the retinal ganglion cell population, while a decoder samples from this latent space to to generate the appropriate future scene frame. By comparing latent representation of retinal activity from three natural movies, we find that the retina has a generalizable encoding for time in natural scenes, and that this encoding can be used to decode future frames with up to 17ms resolution. Lastly, we explore methods to efficiently scale small population models up to a large population using an aggregate approach

A Chronology of UMD Events (1895-1984)

This chronology of events includes 59 pages of events from 1895 though December 1983, with the year listed on the left and a brief description of the event given on the right. Early events have only the year listed; more recent events include the month or month and day as well

Computer assisted skull base surgery: a contemporary review.

Skull base surgery has evolved significantly since Harvey Cushings first descriptions in the early 1900s. Computer aided surgery (CAS) applications continue to expand; they include virtual surgical planning, augmented and virtual reality, 3D printing of models/cutting guides/implants, surgical navigation, and intraoperative imaging. The authors will review the current skull base CAS literature and propose a computer aided surgical workflow categorizing these applications into 3 phases: 1) Virtual planning, 2) Surgical execution, 3) Intraoperative verification