bluuebunny/crossref_metadata_2025 huggingface dataset:
Congenital small bowel abnormalities and their surgical management
Authors: King Sebastian K. , Teague Warwick J.
Published: October 2022

Congenital small bowel abnormalities comprise intestinal atresias, duplication cysts, Meckel’s diverticulum, meconium ileus, and malrotation (with or without volvulus). The presentations and diagnostic pathways for these abnormalities vary, and require an in-depth understanding of each condition. While most may be managed semi-urgently, malrotation with volvulus is a true surgical emergency and requires immediate attention and operative intervention to prevent a potentially catastrophic loss of the midgut. This chapter provides an understanding of each of these abnormalities, with a focus upon their embryological basis, their presentations, and the operative approaches to correct these congenital conditions.
Peptic ulcer disease of the duodenum
Authors: Søreide Kjetil
Published: October 2022

Understanding and management of peptic ulcer disease have changed dramatically over the past decades. Once a frequent surgical disorder for which several operations were invented and tested, it is now largely a medical condition treatable with appropriate drugs and antibiotics. The discovery of Helicobacter revolutionized the understanding of the disease and led to a shift in management. Complications still occur, largely in the form of bleeding or perforation or, rarely, obstruction. Most bleeding episodes can be managed without surgery in the modern multidisciplinary medical centre, either by endoscopy or interventional radiology. Surgery is still needed for perforations, which may be associated with sepsis and organ failure in the sickest patients. While demography and management has shifted in the high-income country populations, with more elderly and comorbid patients presenting with this disease, many regions in low- and middle-income countries still experience a high disease burden in the young to middle-aged population. This chapter reviews the changes in peptic ulcer management and discusses current management strategies.
Ileus and chronic intestinal pseudo-obstruction
Authors: Vather Ryash , Bissett Ian P.
Published: October 2022

‘Prolonged postoperative ileus’ (PPOI) is an absence of gut function as defined by two or more of nausea/vomiting, inability to tolerate oral diet over 24 hours, absence of flatus over 24 hours, distension, or radiological confirmation of ileus—occurring on or after the fourth postoperative day. The aetiology of ileus is multifactorial with early postoperative gut dysfunction more influenced by opioid administration and autonomic shift, and the sustained dysfunction seen in PPOI more related to inflammation. Clinical risk factors that predispose to postoperative gut dysfunction include male sex, open surgery, increased operative bowel handling, operative duration, blood loss, and increased perioperative crystalloid or red cell transfusion. Preventive measures for PPOI are best addressed by considering the elements which comprise Enhanced Recovery After Surgery protocols viz. fluid restriction, spinal analgesia, early oral feeding, early mobilization, avoidance of opioids, and careful electrolyte monitoring. Management involves exclusion of more sinister pathology by way of cross-sectional imaging followed by correction of electrolyte derangements, nasogastric tube insertion, weaning of opioid analgesia, and use of parenteral nutrition as required. Chronic intestinal pseudo-obstruction (CIPO) is rare, and is underpinned by disease processes that interfere with neurogenic or myogenic small bowel activity. The diagnosis of CIPO is difficult to make and is generally one of exclusion. Management is multidisciplinary and focuses on ensuring nutritional needs are met (either orally or parenterally), treating bacterial overgrowth, and slowing progression of the underlying disease process. There is an evolving role for prokinetics. Surgical options for CIPO include small bowel bypass, resection, diversion, and transplantation.
Biliary and pancreatic sphincter of Oddi disorder
Authors: Ratnayake Chathura B.B. , Bekkali N.L. , Oppong Kofi W. , Pandanaboyana Sanjay
Published: October 2022

Dysfunction of the sphincter of Oddi is considered to be due to an episodic increased pressure. The ROME III classification, the previously widely accepted framework for defining the condition, has now been replaced by the ROME IV classification. This is largely due to evidence from the EPISOD trial which indicated that sphincter of Oddi manometry did not predict the response to endoscopic sphincterotomy. A systematic and structured approach towards investigating patients who present with post-cholecystectomy biliary- or pancreatic-type pain is imperative in this complex group before their symptoms are attributed to sphincter of Oddi dysfunction. Endoscopic ultrasound can play an important role in identifying occult choledocholithiasis. Endoscopic retrograde cholangiopancreatography on the other hand carries risks in this setting and clear evidence for its benefit is limited to the management of common bile duct stones and papillary stenosis. Biliary and pancreatic sphincter of Oddi dysfunction is likely to be the cause of post-cholecystectomy pain in a small minority of these patients. The majority will have no structural cause identified and will have functional abdominal pain, the aetiology of which is unclear but represents a complex multifactorial disorder of the brain–gut axis.
Malignant tumours of the duodenum, ampulla, and small bowel
Authors: Klaiber Ulla , Hackert Thilo
Published: October 2022

Malignant tumours of the duodenum, ampulla of Vater, and the small bowel are rare tumours of the digestive system, some of them related to genetic disorders such as polyposis syndromes, but also occurring sporadically. While those situated in the duodenum and ampulla are easily accessible by endoscopy with biopsy and histological proof of the lesion, small bowel tumours located distal to the ligament of Treitz can be diagnostically challenging even when advanced endoscopic techniques are used and cross-sectional imaging methods are the more important tools to find and characterize such tumours. Curative surgery is the treatment of choice for all the mentioned malignancies if no distant metastases are found. For duodenal and ampullary malignant tumours, partial pancreatoduodenectomy should be performed; for tumours of the small intestine, surgery comprises segmental bowel resection including the adjacent mesentery with the draining lymph nodes. Adjuvant therapy is not standardized today but may be beneficial in certain subgroups of patients (i.e. nodal positive). Protocols that are applied in ampullary cancers follow the histological differentiation of the tumour targeting either pancreatobiliary (i.e. gemcitabine, FOLFIRINOX) or intestinal (i.e. FOLFOX) cancers. For small bowel cancer, protocols follow standards of colorectal cancer treatment. Neoadjuvant therapy has no defined role in any of the three malignancies. In metastatic tumours, surgery may be indicated for palliative treatment (i.e. obstruction or bleeding) or with a curative approach in selected patients especially in those showing an intestinal differentiation.
Small bowel mesenchymal tumours
Authors: Glyn Tamara , Frizelle Frank
Published: October 2022

Mesenchymal tumours of the small bowel are tumours originating from mesodermal-derived precursor cells that develop into bone, cartilage, or other connective tissues, such as blood vessels, adipose tissue, smooth muscle, or fibroblasts. Most are found outside the abdomen; however, some can be found in association with the small bowel. These include gastrointestinal stromal tumours, leiomyosarcomas, leiomyomas, lipomas, small bowel desmoids, as well as rare entities such as clear cell sarcoma, inflammatory myofibroblastic tumours, and neurogenic polyps (schwannoma, granular cell tumour, perineurioma, neurofibroma, ganglioneuroma, and gangliocytic paraganglioma). These tumours are rare and their clinical presentation is usually non-specific, usually with bowel obstruction or bleeding. The difficulty accessing the small bowel for investigation and their rarity makes the detection of these tumours a challenge. Treatment and outcome depend on the specific histopathology of the lesions.
Duodenal and small bowel injuries
Authors: Smith Martin D. , Jennings Vicky A. , Devar John
Published: October 2022

Injury to the duodenum and small bowel is relatively common and occurs with both blunt and penetrating trauma. A knowledge of the mechanism of the injury is essential in determining its likelihood and extent and, most importantly, in planning management. Trauma to these two organs is often associated with other injuries and it is these (e.g. vascular injuries) that often determine the outcome. The management priority in all patients is to first stabilize them haemodynamically. Once this is achieved, investigations to determine the extent of the injury as well as the presence of associated injuries is important in developing a treatment plan. Grading the severity of the injury and the stability of the patient are important in defining this plan. Good quality cross-sectional imaging and ultrasound examination have become very important in decision-making. The role of diagnostic laparoscopy is limited. The anatomical site of the duodenum protects it from penetrating injuries and makes diagnosis particularly difficult after blunt trauma. The grading of duodenal injury must account for its intimate relationship with the head of the pancreas, although isolated duodenal injuries do occur. Most penetrating injuries of the abdomen are managed operatively, although there is some evidence to support selective conservative management. If there is good blood supply to the small bowel, primary repair will be possible except when the damage control approach is indicated (due to patient instability). Blunt trauma is much more difficult to manage as early diagnosis can be difficult and delayed diagnosis can have serious consequences. In summary, the majority of injuries to the duodenum are secondary to penetrating trauma. Most can be closed by simple techniques, which include primary repair and duodenoduodenostomy. For more complex injuries, a Roux-en-Y duodenojejunostomy is recommended. The overall management of complex pancreaticoduodenal injuries should ideally be individualized, and surgeons should have a flexible strategy and be familiar with the full range of techniques required for repair.
Clinical Course and Adulthood Outcome in Tourette Syndrome
Authors: Bloch Michael H.
Published: October 2022

This chapter summarizes theexisting literature on the long-term course of Tourette syndrome (TS). Ticsymptoms typically reach their worst-ever severity between ages 10–12 years.Children with tics tend to become more aware of premonitory urges and displaymore complex tics as they grow older. One-half to two-thirds of children withTS experience a significant decline of tic symptoms that roughly coincides withadolescence. There is no evidence to suggest that pharmacological or behavioraltreatments for tics affect long-term prognosis, although research examining thequestion is lacking. Comorbid attention-deficit/hyperactivity disorder symptoms,when they occur, typically precede the onset of tics, and comorbid obsessive–compulsivesymptoms (OCS) usually follow the onset of tics. The presence of OCS inadulthood is highly correlated with the persistence of tic symptoms intoadulthood and not strongly related to the presence of OCS in childhood. Poorfine motor skills are associated with the persistence of tic symptoms intoadulthood. Smaller caudate volumes are associated with the persistence of ticsymptoms into adulthood.
Health Outcomes, Health Status, and Mortality in Tourette Syndrome and Chronic Tic Disorder
Authors: de la Cruz Lorena Fernández , Mataix-Cols David
Published: October 2022

Current knowledge on the health status, health outcomes, and causes of mortality in Tourette syndrome (TS) and chronic tic disorder is very scarce. This chapter summarizes the available literature on the topic and highlights the strengths and weaknesses of the studies conducted to date. These previous works have suggested associations between TS and chronic tic disorder and a range of health conditions, including autoimmune disorders, common allergies and respiratory diseases, sleep difficulties, and metabolic and cardiovascular outcomes. In addition, the risk of premature mortality in tic disorders has been shown to be higher than that in the general population. Although other specific causes of death are yet to be examined in detail, deaths by suicide in TS and chronic tic disorder have been shown to be significantly higher than those in matched controls. Taken together, these results highlight the need to monitor the general health of individuals with TS or chronic tic disorders. The chapter also suggests further lines of research in this underresearched area of study.
Genetic Susceptibility in Tourette Syndrome
Authors: Abdallah Sarah B. , Fernandez Thomas V.
Published: October 2022

Early twin and family studies point to a significant genetic contribution to Tourette syndrome (TS). Informed by early segregation analyses in TS families pointing to a single-gene autosomal dominant inheritance pattern with partial penetrance, initial efforts at gene discovery in TS utilized parametric linkage analysis in large multigenerational families but failed to identify a single specific genetic locus. Later segregation analyses supported the current characterization of TS as a complex, genetically heterogeneous disorder. Nonparametric linkage analyses have yet to identify common TS risk alleles. Candidate gene association studies in TS have not yielded significant reproducible findings. Genome-wide association studies (GWAS) have proven valuable for identifying and replicating loci for common complex traits and disorders across the medical field. A GWAS meta-analysis of almost 5,000 cases identified a significant locus in FLT3. Polygenic risk scores, calculated from the most recent TS GWAS summary statistics, have shown correlation with tic severity and affected status in independent samples. There has been an increasing effort to evaluate the contribution of rare allele variants toward TS. Recent studies have found a greater burden of rare copy number variants in TS cases; the largest study to date identified NRXN1 and CNTN6 as TS risk genes. Identifying rare de novo single nucleotide variants and indels in more than 800 parent–child trios has so far identified six likely TS risk genes (WWC1, CELSR3, OPA1, NIPBL, FN1, and FBN2), which present an enriched function for cell polarity.
Abnormalities of Neural Microcircuits in Tourette Syndrome
Authors: Dyke Katherine , Brandt Valerie , Bäumer Tobias , Münchau Alexander
Published: October 2022

Transcranial magnetic stimulation (TMS) coupled with electromyography allows for extensive study of the motor system and related microcircuits. By varying TMS intensity and interval between pulses, it is possible to probe a number of physiological mechanisms. In contrast to magnetic resonance imaging approaches, TMS is less sensitive to motion. However, although data loss due to movement can be minimized in TMS studies, the impact of potential tic suppression should be considered while interpreting this work, as should the challenges of attempting to define what constitutes a rest state in TS. Complex interactions across numerous circuits, between causal and consequential adaptations and states of activation and rest, are likely and require much additional research to disentangle. In addition to being a useful tool for understanding microcircuits, forms of TMS have been explored as potential therapeutic interventions, as has transcranial direct current stimulation. The evidence for effectiveness of these treatments is mixed, and they are currently not recommended outside of experimental trails. Larger scale studies with appropriate controls are needed to better understand if and how these approaches can help reduce tics.
Neurobiology and Functional Anatomy of Tic Disorders
Authors: Greene Deanna J. , Kim Soyoung , Black Kevin J. , Schlaggar Bradley L.
Published: October 2022

This chapter summarizes the highly valuable contribution of magnetic resonance imaging (MRI) to the understanding of the functional anatomy of tics and related disorders. Structural MRI studies have revealed altered striatal volumes in children and adults with Tourette syndrome (TS), although results are inconsistent. Cortical thinning in sensorimotor regions has been detected in children and adults with TS, with correspondence between cortical region and types of tics. Whereas adults with TS show cortical thinning and reduced gray matter volume in prefrontal regions, suggesting a failure in neural compensation to control tics into adulthood, results from children with TS are mixed. Functional MRI (fMRI) studies examining tic-related activity suggest that the supplementary motor area is involved in the premonitory urge, whereas fMRI studies examining motor and cognitive control in TS report inconsistent findings. Functional connectivity MRI studies suggest complex differences in brain networks. This chapter discusses limitations of the existing studies and future directions, including the necessity to mitigate motion artifacts because they can cause systematic alterations in MRI measures.
Pathways from Genes to Symptoms in Tourette Syndrome
Authors: Eapen Valsamma , Perkes Iain , Golf Roxanne
Published: October 2022

Tourette syndrome (TS) is not a unitary condition but, rather, heterogeneous in clinical presentation, course, treatment response, and longitudinal outcomes. This chapter offers a critical commentary on the varying phenotypic presentations and the associated etiological underpinnings. Potential endophenotypes linking the genetic architecture with the clinical phenotypes are described. Gender-dependent differences in the phenotypic expression as well as the presence of commonly encountered comorbidities such as obsessive–compulsive behavior/disorder and attention-deficit/hyperactivity disorder may indicate different etiological pathways and pathogenesis. Additional factors that may influence the phenotypic expression of TS include prenatal and perinatal difficulties and immunological factors. The clinical phenotype and the severity of symptoms, as well as the associated psychopathology observed in TS, may be influenced by the nature and extent of involvement of the cortico-striato-thalamo-cortical circuitry and the unique contribution of both the genetic and nongenetic factors at play as well as the timing of events during the developmental period. Thus, there may be shared molecular genetic pathways affecting development across diagnostic boundaries mediated through neurodevelopmental genes, but the clinical phenotypic expression may be further shaped by other nongenetic factors. This chapter focuses on the pathogenetic pathways of the distinct and overlapping phenotypes of TS. Currently understood etiologies and phenotypes are discussed, as are underexplored factors in the pathogenesis. Endophenotypes are considered with respect to how they may mediate between genotype and phenotype. The chapter considers the reasons for etiological ambiguity and suggests future research directions to meet some of these challenges.
Clinical Rating Instruments in Tourette Syndrome
Authors: Cavanna Andrea Eugenio
Published: October 2022

The complex motor and behavioral phenotype of Tourette syndrome (TS) presents a unique challenge to measurement and clinical observations. Thorough neuropsychiatric assessments are the gold standard, although standardization and quantification of behavioral symptom severity are often difficult, posing a problem for interventional studies in particular. Different clinician-, informant-, and self-report rating instruments are available for tics and associated phenomena, for use in clinical practice and/or research settings. Some scales fall short of measuring the different dimensions of tic symptoms, such as frequency, intensity, interference, and impairment. The visible and audible nature of core TS symptoms allows direct observation of these symptoms using specific video protocols. A wide range of psychometrically validated clinician- and self-rated measures for obsessive–compulsive behavior, attention-deficit/hyperactivity disorder, and depressive and anxiety symptoms are also available for use in clinical practice and/or research settings. The use of behavioral measures with adequate psychometric indices is recommended. The potential differences between information gathered from clinicians and patients should always be taken into account. It is recommended that clinicians and researchers combine information from professionals and patients (as well as informants if possible) to ensure that the information gathered is comprehensive and accurate.
Neuropsychological Assessment in Tourette Syndrome
Authors: Murphy Tara , Czernecki Virginie , Tarnok Zsanett , Stark Daniel
Published: October 2022

Neuropsychological research and its clinical applications for those with Tourette syndrome (TS) are a promising area. Previous limitations in the literature are now being addressed and include factors such as controlling for the presence of co-occurring conditions, the separate study of children and adults, examination of factors such as time since onset of tics, and translation from the laboratory to the clinic. This chapter discusses the literature on the major domains of cognition and adaptive behavior in TS, with an emphasis on strengths and weaknesses. There is a focus on recent literature (published since 2012), but the chapter includes important older studies on intellectual function, language, learning and memory, attention, and executive function. Importantly, the chapter independently reports on child and adult studies and their implications. The chapter then discusses what is known about the real-world behavioral sequelae among individuals with TS, including adaptive behavior, as well as educational and employment outcomes. The chapter focuses on the potential neuropsychological mechanisms that may be playing out to impact on these areas of life. The role that neuropsychological factors have had in the understanding of outcome in interventions is also reviewed. The chapter then focuses on the clinical application of the corpus of literature on neuropsychology in TS. It discusses the importance of using the research findings along with clinical decision-making, considering cultural factors, limitations of tests, and the complexity of TS in the formulation to guide understanding and intervention for the individuals who live with the condition.
Behavioral and Cognitive–Behavioral Therapy for Tourette Disorder
Authors: McGuire Joseph , Capriotti Matthew R. , Woods Douglas W. , Piacentini John
Published: October 2022

Although pharmacological interventions are efficacious for reducing tic severity, they yield suboptimal symptom relief for most patients and are often associated with side effects that limit long-term tolerability. Behavioral and cognitive–behavioral therapies have demonstrated efficacy for reducing tic severity and tic-related impairment in patients with Tourette disorder. This has led numerous professional organizations to recommend behavioral therapies such as habit reversal training and the Comprehensive Behavioral Intervention for Tics as first-line treatments for Tourette disorder. This chapter provides an overview of different behavioral and cognitive–behavioral therapies for Tourette disorder and reviews the extant evidence for each therapeutic approach. The chapter highlights challenges confronting behavioral and cognitive–behavioral therapies, discusses treatment mechanisms, and identifies steps to overcome these treatment challenges.
Treatment of Psychiatric Comorbidities in Tourette Syndrome
Authors: Cardona Francesco , Rizzo Renata
Published: October 2022

Behavioral treatment should be recommended as initial treatment for patients with Tourette syndrome (TS) or other tic disorder and attention-deficit/hyperactivity disorder (ADHD), especially if symptoms are mild or parents refuse pharmacological treatments. Although obsessive–compulsive disorder (OCD) and TS are closely related, no clinical trials have specifically evaluated the treatment of OC symptoms in TS patients. Monotherapy with serotonin reuptake inhibitors (SRIs) or selective serotonin reuptake inhibitors (SSRIs) has been proven to be efficacious in the treatment of OCD patients, both adults and children, in the short term as well as the long term. No individual drug in these classes has demonstrated a superior efficacy to the others. However, nearly half of OCD patients do not respond completely to SSI/SSRI monotherapy, and even among the responders, few become asymptomatic. Various strategies have been proposed for OCD nonresponders: increasing doses, switching to another drug, augmentation strategies, and novel treatments. OCD patients with comorbid chronic tics or TS show a lower response rate compared to those without tics, both in term of percentage of responders and in terms of symptom reduction. An increased rate of response to antipsychotic augmentation in OCD patients with comorbid tics compared to those without has been reported in only one study. Despite the high rate and the clinical relevance of other psychiatric comorbidities (non-OCD anxiety disorders, self-injurious behaviors, and disruptive behaviors) in TS patients, only a few studies have been devoted to investigating a specific therapeutic approach in these patients.
Information and Social Support for Patients and Families
Authors: Müller-Vahl Kirsten R.
Published: October 2022

For the vast majority of the patients and parents, it is a relief—and not a burden—to receive the diagnosis of Tourette syndrome. However, the diagnosis process should be accompanied by detailed information about different aspects of the condition. Students with tics or Tourette syndrome face numerous academic, behavioral, and social challenges. Most of the impairment appears due to associated disorders. Comprehensive psychoeducational and functional behavioral assessments enable the school team to develop appropriate accommodations and interventions. Providing a supportive environment, nurturing the child’s strengths and talents, and providing resources and support for the parents in service of the child can help the student overcome any challenges and be successful in school.
Information and Support for Educators
Authors: Pruitt Sheryl K. , Packer Leslie E.
Published: October 2022

Students with tics or Tourette syndrome face numerous academic, behavioral, and social challenges. Most of the impairment appears due to associated disorders. The emergence of different symptoms and disorders over time has significant implications for educators. In many cases, a student’s symptoms or challenges will change during the school year or over summer vacation, and the accommodation plan that was appropriate and effective at one point in time may suddenly no longer be effective. Comprehensive psychoeducational and functional behavioral assessments enable the school team to develop appropriate accommodations and interventions. Providing a supportive environment, nurturing the child’s strengths and talents, and providing resources and support for the parents in service of the child can help the student overcome any challenges and achieve success in school.
Tourette Syndrome Support Organizations Around the World
Authors: Anderson Seonaid , Heijerman-Holtgrefe Annet , Hartmann Andreas
Published: October 2022

This chapter discusses what Tourette Syndrome patient associations (TSPAs) around the world have to offer to patients, their relatives, and professionals. What is their added value? And how can this improve the daily lives of people with Tourette syndrome? What is the current status of TSPAs around the world? An overview of the most important services and contact details of TSPAs are provided. It is possible to thereby quickly obtain a picture of the services that the organization in each country has to offer. Professionals can easily share the information and contact details with their patients and open the way to support in an accessible manner.
Basic Electronics
Authors: Misulis Karl E. , Johnson Evan M.
Published: October 2022

This chapter expounds on the concept of basic electronics and the progress in electronics, developed through scientific investigations and practical utility. Conductors are the most basic circuit element which could be classified by their ability to conduct charge (conductors, non-conductors, and semiconductors). Resistors, on the other hand, resist the flow of current, while capacitors are elements storing energy by separation of charge. The chapter also explains the function and significance of diodes, inductors, amplifiers, and analog filters. For neurophysiology purposes, most equipment use either disk electrodes or needle electrodes to conduct biologic signals effectively. Then, an analog-to-digital converter (ADC) could help transform the signals into digital data that would undergo analog-to-digital conversion.
Electroencephalography
Authors: Misulis Karl E. , Johnson Evan M.
Published: October 2022

This chapter looks into electroencephalography (EEG). EEG physics includes the basic understanding of cellular biology and physiology of excitable tissue such as neurons. Normal EEG activities consist of a wide range of activities like biophysical mechanisms of how the electrical activity is recorded as the generated EEG. Posterior dominant rhythm (PDR) and sleep spindles are examples of a wide variety of patterns illustrating EEG generation. On the other hand, abnormal EEG activities are illustrated by spikes, sharp waves, and slowing. Additionally, quantitative EEG is an umbrella term for advanced data handling allowing detection of seizure and spike, mapping, and spectral array.
Electromyography and Nerve Conduction Studies
Authors: Misulis Karl E. , Johnson Evan M.
Published: October 2022

This chapter discusses the methods of data acquisition via electromyography (EMG) and nerve conduction studies (NCS). Moreover, EMG and NCS are the basic components of neuromuscular diagnostics. Modern EMG equipment features fundamental elements such as recording hardware and software, stimulator, display, and storage. Thus, the digital transformation of EMG allowed for the digital manipulation of the data and improved acquisition. The chapter also expounds on the spectrum of normal and abnormal responses in NCV and EMG such as compound motor action potential (CMAP), denervation of muscle, and axonal neuropathy. It explains the sensory conductions, motor conductions, and EMG of Guillain-Barre syndrome, carpal tunnel syndrome, muscular dystrophy, and myasthenia gravis.
Ultrasound
Authors: Johnson Evan M.
Published: October 2022

This chapter explains the features and functions of sound. It discusses how sound and radio waves travel at different speeds as it is dependent on the medium it is traveling in. Sound waves travel continuously through a medium while being subjected to absorption before they encounter a medium with a different impedance. Moreover, ultrasound is primarily known to be the sound waves at frequencies higher than a human can hear. As an example of a technology using sound, sonography needs a controlled generation of sound to produce medical imaging. A sonography system typically consists of a computer with a monitor connected to a probe with a piezoelectric transducer.
X-Ray and Computed Tomography
Authors: Johnson Evan M.
Published: October 2022

This chapter focuses on the features of x-ray and computed tomography (CT). X-ray uses a form of radiation to conduct basic body imaging and destroy tumor beds to facilitate cancer therapy. However, ionization is one of the downsides of x-rays as it could result in a carcinogen. On the other hand, CT is a diagnostic imaging technique that uses x-ray projections to produce non-invasive cross-sectional imaging. X-rays and CT systems share components such as electron beam, x-ray generation, and detectors. Additionally, both technology is used for processes such as angiography, venogram, and myelogram. The chapter also lists barium and iodine as the contrast agents for x-ray processes.
Magnetic Resonance Imaging
Authors: Doyle Eamon , Johnson Evan M.
Published: October 2022

This chapter discusses magnetic resonance imaging (MRI), which had become a key diagnostic technology for clinicians and researchers. MRI is rooted in nuclear magnetic resonance (NMR) technology. It tackles the process of forming signals with the help of free induction decay (FID). The main magnetic field in MRI machines is designed to vary less than one part-per-million over the whole imaging bore. Moreover, the inclusion of gradient fields allowed the concept of direction and the generation of a new type of echo, the gradient echo. The variation of spatial encoding is recorded by changing the timing strength, duration, and shape of gradient fields and radio frequencies (RF).
Laboratory Studies
Authors: Misulis Karl E.
Published: October 2022

This chapter expounds on the practice of laboratory studies. Laboratory studies have been key to neurologic diagnosis, but their interpretation has become increasingly complex over time. Routine analytic laboratory studies are vital for their identification of medical conditions with neurologic implications, while immunological studies are primarily focused on identifying antibodies responsible for numerous diseases. The measurement of antibodies is performed depending on the purpose. ELISA is one of the tools used to measure levels of specific antibodies. While smears, cultures, nucleic acid analysis, and serology could identify infections, DNA analysis is used to diagnose inherited diseases. Then, neuropathology utilises a multimodal approach to neurologic disease antemortem and postmortem.
Raymond Hynes
Authors: Towers Anna
Published: October 2022

Sometimes a family is fortunate enough to have significant resources to face a world that seems to have fallen apart. This was the case for Raymond Hynes and his family when they learned of his incurable cancer. The Hyneses had their way of dealing with this disaster, a way that was different from what the palliative care team wanted to see. The different perspectives may have represented cultural differences between the family and the medical professionals. The members of the Hynes family were practical and stoical; when challenged by life events, they typically sought a common-sense, step-by-step solution, and that is how they preferred to deal with the illness. The team, however, kept expecting more expression of feeling. Silence was a powerful force that informed the family’s actions. Nevertheless, the family and the team managed to navigate a course that led to a successful death at home.
Rose Picard
Authors: Towers Anna
Published: October 2022

Rose Picard had led a full and happy life. When, at the age of 72, the gynecologist told her that she had ovarian cancer, she adapted quickly to the news. When chemotherapy failed and she transferred to the Palliative Care Unit, she did so with equanimity. Her husband and children had more difficulty. Mrs. Picard had an unshakable faith and joie de vivre that impressed her healthcare givers. She prepared for her death; when she was ready, however, death did not come quickly.
Leonard Patterson
Authors: Lambrinidou Yanna
Published: October 2022

Leonard Patterson was a 62-year-old White American man with rectal cancer. His poverty, tumultuous relationships with his family, and unmanageable pain produced a cluster of unresolved problems in the final months of his life. Despite the painstaking efforts of hospice to offer him a peaceful death and his family a smooth transition to a life without him, this case left many of its participants unsettled. One of the questions it raises is whether the best of palliative care can ease shattered lives in situations that are not only complex but also depart from the economic, social, and cultural “norm” of the families that hospice tends to serve.
Martin Roy
Authors: Towers Anna
Published: October 2022

Martin Roy was only 37 years old when he learned that his cancer was far advanced. By his own account he had already had a full and fulfilling life, and he spent his final months preparing his family for his death. Although controlling Martin’s symptoms was not easy for the palliative care team, with a combination of inpatient and home care they succeeded in finding a style of care that kept him comfortable and suited the family. Something other than symptom control proved challenging to the staff, however: Martin seemed almost too accepting of his situations. What accounted for his exceptional ability to adapt to dying at an early age? Was he simply a “good coper” or was he “euphoric” and “in denial”? What was really going on with him?
Jasmine Claude
Authors: Towers Anna
Published: October 2022

When Jasmine Claude’s lymphoma was first treated with chemotherapy, the cancer was put into remission; however this was short-lived. She was only 37 years old when the tumors started to grow again, and her oncologist tried three different regimes to get her into remission. In her fourth year of treatment she began to develop abdominal pain. The oncologist consulted the Palliative Care Service to help control her symptoms, and the service followed her as an outpatient. She continued to receive palliative chemotherapy for many months after this. When the oncologist told her that the abdominal tumor was growing despite the chemotherapy and that he would have to stop the treatment, Mrs. Claude began to receive palliative home care. She was feeling tired and less able to go out but was otherwise not feeling too bad. She carried on with her daily routine as much as she could and seemed surprisingly cheerful and serene. It was unusual for the palliative care staff to witness such serenity, which derived from an unshakable faith in God that Mrs. Claude had developed over the years. Their reactions ranged from curiosity, fascination, and inspiration to skepticism. This narrative describes not only an experience of palliative care, but also an exploration of the experience of faith, as seen within a palliative care context.
Katie Melnick
Authors: Lambrinidou Yanna
Published: October 2022

God was omnipresent in Katie Melnick’s life. She saw signs of him everywhere she went. Even during the last stages of her lung cancer, after the disease had spread to her brain, Mrs. Melnick felt a deep sense of peace. Her hospice caregivers marveled at the depth and resoluteness of her faith. Mrs. Melnick’s dying took four months longer than her doctors prepared her to expect. In contrast to her own serenity, family secrets caused pain, confusion, and guilt, especially for Mrs. Melnick’s adult daughter. As the Melnicks relived old hurts, they also found unexpected opportunities for love and reconciliation.
Joey Court
Authors: Lambrinidou Yanna
Published: October 2022

The death of a child is a relatively rare event in medicine. Joey Court was born with an unusual and invariably fatal medical disorder. His parents anticipated Joey’s death from the first year of his life but tried their best to treat him as they would any other child. Nine years later, they made the difficult decision to stop his life-prolonging treatment and called on hospice for palliative home care. To their surprise, Joey lived another five months. This narrative is about a family coming to terms with a child’s death. It touches on several themes in pediatric hospice care: the decision to terminate aggressive treatment, the anticipation of an unnaturally premature death, the grief and bereavement of family members of all ages, and the question, “why?”
Surgical airway
Authors: Bradley William P. L. , Chapman Gordon A.
Published: October 2022

Maintenance of oxygenation is the fundamental principle underlying airway management in anaesthesia, and this is most often achieved via a supraglottic approach. However, there are times when infraglottic airway access may be required. Surgical airways in oromaxillofacial surgery may be performed as planned elective procedures or may be undertaken in an emergency, as part of an airway rescue strategy, in the ‘can’t intubate, can’t oxygenate’ (CICO) situation. Various surgical techniques may be employed depending upon the circumstances, acuity, patient pathology, equipment availability, and operator skillset. This chapter discusses the range of surgical approaches, outlining the technique, indications and contraindications, respective advantages and disadvantages, and potential complications.
Sedation
Authors: Mann James W. D. , Yuen Vivian
Published: October 2022

Procedural sedation has a long and often fraught history in oromaxillofacial surgery and dentistry. When performed correctly, it improves patient comfort, reduces anxiety, and facilitates medical interventions and procedures to be performed without the need for general anaesthesia. There is a growing demand for procedural sedation across specialties, which is being met by anaesthetists and non-anaesthetists. There is a significant heterogeneity of sedation practice—in part due to the variety of sedative agents and modes of delivery available, but also the level of training of the individual sedation practitioner and the nature of the procedures. Complications arise from the changeability of the language used to describe sedation states, inconsistency in the standards of monitoring, and variation in the abilities of staff to rescue patients from a deeper-than-intended level of sedation. Sedation in oromaxillofacial surgery presents additional risk due to the nature and site of the procedures, where access to the airway may be restricted. Sedation agents and techniques appropriate to these procedures are outlined in this chapter. Procedural sedation warrants the application of minimum standards to ensure safety by adopting recognized guidelines. There is a need to assimilate and collect data on the incidence of adverse events and outcomes to help guide future practice and promote patient safety. Whether this is achieved on a voluntary self-reporting basis or via a national audit project remains to be seen. Future agents and devices will hopefully confer a safety advantage, but better application of existing knowledge and skills would confer an enormous safety benefit.
Hypotensive anaesthesia
Authors: Hodge Kimberley , Ward Patrick A. , Irwin Michael G.
Published: October 2022

Hypotensive anaesthesia describes the deliberate lowering of a patient’s blood pressure during surgery. This technique is undertaken for a variety of reasons including optimizing visualization of the surgical field, reducing blood loss, and improving surgical accuracy. It is commonly achieved via pharmacological manipulation of the systolic blood pressure using a variety of agents. Other non-pharmacological strategies to minimize blood loss and, therefore, optimize the surgical field, are also explored within this chapter. Utilization of hypotensive anaesthetic techniques can be dangerous as it can result in end-organ ischaemia such as brain hypoperfusion, acute kidney injury, and myocardial infarction. It is, therefore, imperative to determine whether the risks associated with hypotensive anaesthesia are warranted and the level required. A thorough preoperative assessment of the patient must be undertaken to attempt to stratify risk, and the patient must be informed of the intention to employ the technique as part of the consent process. Should hypotensive anaesthesia be undertaken, it is crucial that the agent used is easily titratable to ensure a minimal and rapidly reversible period of hypotension.
Orthognathic surgery
Authors: Ward Patrick A. , Irwin Michael G.
Published: October 2022

Anaesthesia for orthognathic surgery requires extensive preoperative planning and multidisciplinary care. Patients are generally young and healthy, although there is an increasing trend in treatment of patients with obstructive sleep apnoea which is associated with increased comorbidity. Intraoperatively the airway is ‘shared’ and, therefore, cooperation and communication between the anaesthetist and the surgeon is essential. Generally, a nasotracheal tube is required to allow dental occlusion (as a reference point) perioperatively. Routine insertion of throat packs is no longer indicated, and should be considered on a case-by-case basis only, after discussion with the surgeon. Deliberate hypotensive anaesthesia (to optimize the surgical field and reduce blood loss) should only be undertaken when clearly indicated and should be closely monitored in carefully selected patients. Meticulous suctioning of the oropharynx under direct vision is essential before extubation of the trachea. Carefully planned and coordinated extubation strategies (including potential reintubation) should be agreed by the anaesthetist and surgeon, particularly for patients with intermaxillary fixation devices. Clinical pathways can be developed to improve patient outcomes.
Infection
Authors: Duffen Adam R. , Vaughan David J. A.
Published: October 2022

Oral and dental infections are an extremely common problem worldwide. Most cases can be treated with good oral hygiene and a course of appropriate broad-spectrum antibiotics. Rarely, however, infection can be severe, resulting in localized or systemic spread necessitating hospital admission and urgent surgery and/or supportive critical care management. This chapter explores the pathophysiology and microbiology of dental infections and their associated complications. The anaesthetic management of life-threatening airway compromise and severe sepsis are described, highlighting priorities for clinical assessment, urgent treatment strategies, management of the difficult airway, emergency surgery, and organ support. These are very challenging high-risk cases, associated with significant morbidity and mortality, that necessitate a collaborative approach involving experienced anaesthetic and surgical personnel so that the best patient outcomes can be achieved.
Surgical complications
Authors: Curtin Justin P. , Lee Gene
Published: October 2022

The nature of oral and maxillofacial surgery and the ‘shared airway’ necessitates that surgeon and anaesthetist establish a cooperative approach to patient care, based on constant communication and feedback throughout surgical procedures. A good understanding of each other’s priorities and concerns, and appreciation of each other’s knowledge and skills are essential in optimizing patient safety and outcome. This chapter provides an overview of surgical complications in oral and maxillofacial surgery and their management, from the perspective of the surgeon, which should enable the anaesthetist to gain greater insight and understanding of surgical decision-making and interventions, in order to anticipate or avoid potential problems, and deal with them swiftly and efficiently when they do occur.
Pathophysiology of hypertension
Authors: Mary Sheon , Rossitto Giacomo , Delles Christian
Published: October 2022

Blood pressure is determined by cardiac output and vascular resistance. This chapter explains how renal, cardiac, and vascular mechanisms interact to maintain blood pressure and organ perfusion. In pathophysiological situations, these systems can be dysregulated and lead to hypertension. In patients with primary hypertension, a combination of more subtle changes leads to hypertension, whereas in patients with secondary hypertension, there is predominance of single factors that drive the blood pressure increase. Besides these traditional factors affecting hypertension, new information into genetic influences on the pathogenesis of hypertension have also increased our understanding into the complex mechanisms involved. Understanding these principles provides the rational basis for contemporary antihypertensive therapies.