Fifth Generation Cellular Networks and Neurosurgery: A Narrative Review.

Connectivity is a driving force for productivity across a wide variety of sectors in the 21st century, with health care being no exception. Fifth generation cellular technology (5G) is frequently alluded to in the mainstream media but understanding of the technology and its potential impact is not widespread in clinical communities. It promises unprecedented improvement in speed, bandwidth, reliability, and latency, all of which have significant implications for the way we use wireless data. 5G can be subdivided into 3 parallel technological architectures: extended mobile broadband (eMBB), ultra-reliable low latency communication (URLLC), and massive machine type communication (mMTC). These domains each present different and exciting prospects for the future of health care. This narrative review aims to elucidate the nature of 5G, its context within the development of telecommunications, and describe some of the notable opportunities it presents to the neurosurgical community. In many cases the requisite hardware has already been developed, but use has been limited by the requirements of a fast, reliable, and omnipresent network connection. Examples include telesurgical robots, remote supervision of procedures, integrated smart operating rooms, and clinician telepresence. The events of 2020 and the COVID-19 pandemic have brought the world's attention to digital transformation. The mechanics of 5G connectivity creates the capacity for these changes to be applied practically. An understanding of this technology is essential to appreciate the development and opportunities which will be part of our professional future.

The therapeutic potential of atorvastatin in a mouse model of postoperative cognitive decline.

OBJECTIVE: Postoperative cognitive decline is emerging as a significant complication of surgery among older adults. Animal models indicate a central role of hippocampal inflammatory responses in the pathophysiology of postoperative cognitive decline. We hypothesized that atorvastatin, shown to exert neuroprotective potential in central nervous system (CNS) disorders, would attenuate neuroinflammation and improve cognitive function in mice after surgery and anesthesia. METHODS: C57BL6 adult mice were pretreated with atorvastatin (250 µg) or vehicle, orally, for 5 days before undergoing unilateral nephrectomy under isoflurane anesthesia. We evaluated behavioral parameters related to cognitive function (fear conditioning and Morris Water Maze) and determined systemic and hippocampal interleukin-1ß levels, postoperatively. Endothelial COX-2 expression, gross NF-κB and microglial (IBA1, CD68) activation, synaptic function (synapsin-1, PSD95, COX-2), heme oxygenase-1, and GSK3ß were also examined. RESULTS: Surgery induced a significant reduction in hippocampal-dependent fear response that was attenuated by treatment with atorvastatin, which also preserved spatial memory on day 7 after surgery. Atorvastatin evoked significant protection from hippocampal interleukin-1ß production, but not systemic interleukin-1ß production, accompanied by a marked reduction in hippocampal endothelial COX-2, NF-κB activation and decreased microglial reactivity. Surgery triggered an acute decline in synapsin-1, paralleled by an increase in postsynaptic COX-2 that was partially attenuated by atorvastatin. Furthermore, phosphorylation and inactivation of neuronal GSK3ß was significantly enhanced after atorvastatin treatment. CONCLUSIONS: These findings indicate that cognitive decline is very likely associated with synaptic pathology after systemic and central inflammation induced by peripheral surgery/isoflurane anesthesia and suggest that the anti-inflammatory and neuroprotective properties of atorvastatin provide a rationale for its use as a therapeutic strategy for postoperative cognitive decline.

Development and validation of a computerized model of smiling: Modeling the percentage movement required for perception of smiling in unilateral facial nerve palsy.

BACKGROUND: The inability to smile stands out as a notable difficulty for individuals with facial nerve palsies; a problem that facial reanimation surgery aims to rectify. However, smile reconstruction currently lacks quantitative data by which to objectively measure outcomes. This study aims to identify the relative importance of different oral muscles in terms of smiling, and explore the percentage function that needs to be restored for a smile to be perceived by an observer. METHODS: A computer animation tool was developed to model the oral facial muscles and demonstrate the facial expressions produced by contraction of different muscle groups. By programming a variable unilateral paralysis of the zygomaticus major, the effects of 0-100% function of this muscle can also be seen in a further set of animations using the basic muscular structure of a smile to produce a computerized proxy smile. These animations were shown to 75 adults from the general population who reported those expressions they perceived as a smile. RESULTS: The only facial expression consistently associated with a perceived smile was caused by the combined contraction of the zygomaticus major and the levator anguli oris (P < 0.001). This concurs with previously reported observations of the human smile. Over 70% of the subjects were able to perceive a smile with just 40% function of the unilateral paralyzed zygomaticus major. CONCLUSIONS: These results present an objective target for facial reanimation surgery by which outcomes may be measured. This computerized model also provides a valuable tool for patient education during pre-operative consent.

The role of the TGF-ß family in wound healing, burns and scarring: a review.

It is estimated worldwide that over 6 million people per annum experience a burn injury. Despite advances in management and improved survival rates, the incidence of hypertrophic scarring remains high. These scars are particularly common after burns and are often raised, red, hard and may cause abnormal sensations. Such pathological scarring can lead to severe functional impairment, psychological morbidity, and costly long term healthcare. Wound healing is an inherent process which restores the integrity of the skin after injury and although scarring is a frequent by-product, the scarless wound healing observed in early human gestational fetuses suggests that it is not an essential component of the response. This has lead to a large body of research attempting to understand the mechanisms behind scarring and in turn prevent it. One of the main focuses of recent research has been the role played by the growth factor TGF-ß in the process of both wound healing and scar formation. The three isoforms (TGF-ß1, TGF-ß2 and TGF-ß3) appear to have overlapping functions and predominantly mediate their effects through the intracellular SMAD pathway. Initial research suggested that TGF-ß1 was responsible for the fibrotic scarring response whereas the scarless wound healing seen in fetal wounds was due to increased levels of TGF-ß3. However, the reality appears to be far more complex and it is unlikely that simply altering the ratio of TGF-ß isoforms will lead to scarless wound healing. Other aspects of the TGF-ß system that appear promising include the downstream mediator CTGF, the proteoglycan decorin and the binding protein p311. Other putative mechanisms which may underlie the pathogenesis of hypertrophic scars include excessive inflammation, excessive angiogenesis, altered levels of matrix metalloproteinases, growth factors, and delayed apoptosis of fibrotic myofibroblasts either due to p53 genetic alterations or tensile forces across the wound. If an effective treatment for hypertrophic scars following burns injury is to be developed then further work must be carried out to understand the basic mechanisms of pathological scarring.

The course and variation of the facial artery and vein: implications for facial transplantation and facial surgery.

The main arterial supply of the facial skin envelope is the facial artery which serves as the main pedicle for a number of facial flaps, including a facial transplant graft. This study explored the course of the facial artery and vein, branching patterns, terminations, and anomalous variants. Cadaveric dissections of 201 facial arteries and 198 facial veins were performed. All branches originated from a single facial arterial trunk in 86% of specimens and branching patterns were symmetrical in 53%. The facial artery predominantly terminated as a lateral nasal artery (49%). In 5 cases, the facial artery was undetectable with transverse facial arterial dominance (1 case bilateral). The facial vein was predictable in position except for 2 instances, being replaced by a transverse facial vein (unilateral). Facial arterial dominance in facial blood supply is common but unpredictable. Careful vascular workup prior to facial transplantation and unipedicled flap procedures is therefore essential.