bluuebunny/crossref_metadata_2025 huggingface dataset:
Chorea, Ataxia, and Disturbed Sleep
Authors: Feemster John C. , Louis Erik K. St.
Published: November 2021

A 72-year-old man sought care for predominant choreiform movements, mild gait ataxia, urinary dysfunction, and abnormal nocturnal behaviors. Choreiform movements were nearly constant while awake, vanished during sleep, and predominantly involved his lower extremities and trunk. He also had urinary dysfunction, with urinary hesitancy and frequency. Sleep-related behaviors included sleep talking, sleep singing, sudden single-limb jerking movements, and complex hand movements. He also had daytime sleepiness.

On neurologic examination, abnormal findings included postural instability at baseline with eyes open and a slightly wide-based tentative gait and inability to execute tandem walking. He had intermittent choreiform movements of the legs and the left shoulder. He also had occasional repetitive, periodic, voluntary-appearing, triple flexion–type movements of both legs.

Overnight polysomnography was ordered to evaluate nocturnal movements. Polysomnography revealed rapid periodic leg movements of sleep and rapid eye movement sleep without atonia. Sleep architecture was mildly deranged, with electroencephalographic alpha intrusion throughout nonrapid eye movement sleep, as well as absent slow-wave sleep. Ferritin level was suboptimal. Evaluation of serum for autoimmune encephalitis demonstrated IgLON family member 5 antibody positivity by tissue immunofluorescence assay, confirmed by cell-based assay.

The patient was diagnosed with IgLON family member 5 autoimmune encephalitis and symptomatic rapid eye movement sleep behavior disorder.

The patient was instructed to maintain a safe sleep environment at home and to begin taking melatonin at bedtime. A therapeutic trial of intravenous methylprednisolone, together with mycophenolate mofetil, was followed by improvement in memory, confusion, and hallucinations, waking involuntary movements, bladder dysfunction, and sleep quality.

Rapid eye movement sleep behavior disorder is a parasomnia characterized by rapid eye movement sleep without atonia, the loss or dysregulation of normal rapid eye movement sleep atonia, which is its pathophysiologic signature, and which is permissive for dream enactment behaviors during rapid eye movement sleep.
Rapidly Progressive Gait and Coordination Difficulties
Authors: McKeon Andrew
Published: November 2021

A 59-year-old woman noted sudden onset of slurred speech. Within a few days, she noted double vision, gait unsteadiness, and incoordination of her limbs. She sought care at her local emergency department. Computed tomography and magnetic resonance imaging of the head were negative for stroke. Her symptoms persisted. Neurologic examination indicated a moderate pancerebellar ataxia, without additional abnormalities. Her pursuit eye movements were saccadic. She had binocular diplopia with horizontal, gaze-evoked nystagmus. She had ataxic dysarthria and dysmetria of all limbs. Her steps and walking were irregular and she could not accomplish tandem gait.

Additional neural antibody testing was undertaken, beyond the classic paraneoplastic antibodies. Metabotropic glutamate receptor 1-immunoglobulin G was detected in the serum and cerebrospinal fluid.

The patient was diagnosed with autoimmune cerebellar ataxia.

Because of the reported association of metabotropic glutamate receptor 1-immunoglobulin G with Hodgkin disease and non-Hodgkin lymphoma, positron emission tomography–computed tomography of the trunk (orbits to thighs) was performed, which was negative. After 6 weeks of intravenous methylprednisolone, the patient returned for evaluation. She had a mild ataxic dysarthria and minimal dysmetria of her left upper extremity only. She could tandem walk almost without error, and her gait appeared normal (no longer broad-based). At that point, immunotherapy was discontinued. At last follow-up, her neurologic examination findings remained stable.

The subacute onset and rapid progression of ataxic symptoms in this adult patient led to suspicion for an autoimmune cause.
“Restlessness” After Cancer Diagnosis and Treatment
Authors: Zekeridou Anastasia
Published: November 2021

A 76-year-old woman sought care for unintentional weight loss, hematuria, and fatigue. She was diagnosed with plurimetastatic renal cell carcinoma. After resection of the primary tumor and metastases, she was treated with pembrolizumab, an immune checkpoint inhibitor. The patient experienced involuntary tongue and face movements with dysphagia and weight loss. She was also described as “restless.” At that point, the patient was in cancer remission with ongoing immune checkpoint inhibitor treatment. Blood testing was unremarkable. Brain magnetic resonance imaging showed basal ganglia T2/fluid-attenuated inversion recovery hyperintensities without gadolinium enhancement. Cerebrospinal fluid testing showed slightly increased protein concentration and 8 cerebrospinal fluid-restricted oligoclonal bands. Serum and cerebrospinal fluid testing for neural autoantibodies showed immunoglobulin G immunoreactivity in a mouse tissue indirect immunofluorescence assay, predominantly staining the basal ganglia. The immunoglobulin G was subsequently identified to bind to phosphodiesterase 10A. The patient was diagnosed with paraneoplastic phosphodiesterase 10A-immunoglobulin G autoimmunity manifesting as hyperkinetic movement disorder triggered by immune checkpoint inhibitor treatment. Given the patient’s cancer remission, the immune checkpoint inhibitor treatment was discontinued. She was treated with high-dose intravenous corticosteroids, with improvement of her hyperkinetic movement disorder but persistence of some dystonic movements. Further treatment with oral prednisone did not produce further improvement. The patient was treated symptomatically with onabotulinumtoxinA injections and tetrabenazine, which ameliorated her dystonic movements. Three years after her cancer diagnosis, she was alive and in cancer remission with minimal residual movements. Immune checkpoint inhibitors are monoclonal antibodies targeting “stop signs” of the immune response, which lead to enhanced endogenous responses, including those against cancer. Autoimmune complications are consequences of the enhanced immunity and can affect all organs, including the nervous system.
A Young Man With Visual Field Loss, Decreased Hearing, and Confusion
Authors: Bhatti M. Tariq , Eggenberger Eric R. , Acierno Marie D. , Chen John J.
Published: November 2021

A 27-year-old man noted imbalance and staggering when walking. Vertigo, nausea, vomiting, and mild fever developed. This was presumed to be due to an inner ear infection, and antibiotics were prescribed. He began experiencing intermittent left face and arm numbness, bilateral hearing loss and tinnitus. Audiography indicated low-frequency hearing loss in both ears, left worse than right. He reported headaches and neck stiffness, and his family noticed that he was moody, easily aggravated, and confused, with slow mentation. Magnetic resonance imaging showed patchy, nodular, leptomeningeal enhancement involving both cerebral hemispheres and the posterior fossa, with scattered hyperintense T2 signal changes of the internal capsule and prominent abnormal signal changes in the corpus callosum. Cerebrospinal fluid analysis was remarkable for a markedly increased protein concentration and white blood cells. Eye examination showed 20/20 vision in both eyes with a superior visual field defect in the right eye. Retinal whitening was noted in the vascular distribution of the inferotemporal arcade. Intravenous fluorescein angiography showed delayed filling in this region consistent with a branch retinal artery occlusion and scattered areas of arteriolar wall hyperfluorescence. A diagnosis of Susac syndrome was made on the basis of the branch retinal artery occlusion, magnetic resonance imaging findings, and hearing deficit. Intravenous methylprednisolone was given, followed oral prednisone, which resulted in substantial improvement in headaches and cognition. Cyclophosphamide was also started at the same time as intravenous methylprednisolone. A new visual field defect developed due to a branch retinal artery occlusion in the left eye, which prompted initiation of intravenous immunoglobulin and transition from cyclophosphamide to rituximab. He had no recurrent branch retinal artery occlusions or other relapses of his underlying Susac syndrome on this treatment regimen. Susac syndrome was initially described as a microangiopathy of the brain and retina. It is an idiopathic autoimmune disorder that primarily affects the brain, eye, and inner ear.
Night Sweats and Paraparesis
Authors: Abarbanel David N. , Carabenciov Ivan D.
Published: November 2021

A 78-year-old man sought care for saddle anesthesia, left lower extremity numbness, and bilateral lower extremity weakness. The sensory loss occurred suddenly, starting initially in the left perianal region and over the course of 3 hours extending down to involve the entirety of the left lower extremity. Symptoms were stable until 3 weeks later, when he had a few episodes of urinary incontinence. Diffuse, severe, bilateral, lower extremity weakness developed. The patient reported 6 months of intermittent night sweats. Serum studies were notable for pancytopenia and increased erythrocyte sedimentation rate and levels of ferritin and lactate dehydrogenase. Lumbar puncture showed a mildly increased protein concentration with normal blood cell count, glucose value, and cytologic and flow cytometry findings. Magnetic resonance imaging showed multifocal regions of increased T2 signal throughout the central nervous system including the cerebrum, cerebellum, upper cervical cord, lower thoracic cord, and conus medullaris. Gadolinium enhancement was present in the corpus callosum, cerebellum, and dorsal lower thoracic cord. One week later, 18F-fludeoxyglucose–positron emission tomography/computed tomography showed patchy 18F-fludeoxyglucose activity in the cerebral parenchyma, as well as 2 cutaneous, 18F-fludeoxyglucose-avid soft-tissue nodules. Fine-needle aspiration of 1 of these nodules indicated diffuse large B-cell lymphoma, with no dysplastic abnormalities identified on subsequent bone marrow biopsy. Incisional biopsy of the second soft-tissue nodule showed foci of diffuse large B-cell lymphoma adherent to the lumina of a few small arteries, consistent with a diagnosis of intravascular lymphoma. The patient was diagnosed with intravascular large B-cell lymphoma. At initial evaluation at an outside facility, empiric intravenous corticosteroids were administered. After the biopsy findings of intravascular large B-cell lymphoma, he was started on intermediate-dose methotrexate followed by rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone therapy. He continued to experience severe, bilateral, lower extremity weakness and sensory loss. Two months after diagnosis of intravascular large B-cell lymphoma, he died of medical complications from chemotherapy. Intravascular lymphoma is a rare lymphoma subtype that is typically of B-cell origin. The neoplastic cells preferentially grow within the lumen of blood vessels, potentially due to a lack of cellular machinery required for cellular extravasation and parenchymal invasion.
Seizures 3 Months After Endarterectomy
Authors: McKeon Andrew , Brown Robert D.
Published: November 2021

A 57-year-old woman had development of acute-onset, right-sided weakness and sensory change (face, arm, and leg) when at a casino. She was brought to the emergency department, and her symptoms had essentially resolved upon her arrival. Brain magnetic resonance imaging showed no acute stroke, and a transient ischemic attack was diagnosed. She was transferred to an academic medical center. Investigations showed high-grade left internal carotid artery stenosis; the same day, a stent was placed via endovascular procedure by an interventional neuroradiologist. Magnetic resonance imaging of the head showed an enhancing lesion with surrounding edema in the left frontal and parietal lobes at the cortex, also involving the nearby leptomeninges. Electroencephalography showed potentially epileptogenic discharges over the left central head region. Brain biopsy was performed, which showed abundant CD68+ macrophages, granulomatous inflammation, and necrosis associated with foreign material. The associated lymphocytic infiltrates were predominantly composed of CD3+ T cells and only sparse CD20+ B cells. The foreign material seen was lamellated, amorphous, nonpolarizable, and nonrefractile, typical of hydrophilic polymers commonly used in intravascular medical devices. The patient was diagnosed with seizures caused by multifocal, intracranial, foreign-body, granulomatous reaction to polymers that had embolized to brain parenchyma during the prior endovascular procedure. To suppress this inflammatory reaction, corticosteroids were initiated—intravenous methylprednisolone, followed by an oral prednisone course, with a plan to gradually taper. Antiseizure medication was continued at the same doses. The patient’s seizures remitted initially but relapsed upon corticosteroid dose reduction despite a very slow prednisone taper. At that point, 18 months after the initial onset of seizures, the patient had cushingoid features, depression, and chronic insomnia. During the next year, 2 steroid-sparing strategies were employed sequentially. In patients who have received neurovascular medical device therapy and have subsequent development of seizures, focal neurologic deficit, headache, or encephalopathy, central nervous system inflammation triggered by retained foreign-body material should be considered as a potential cause.
Acute Quadriparesis in a Smoker
Authors: Zalewski Nicholas L.
Published: November 2021

A 51-year-old woman was seen for evaluation of transverse myelitis. Pertinent medical history included hypertension, hyperlipidemia, and 50 pack-years of cigarette smoking. Two months earlier, she was shopping and suddenly had excruciating pain in her upper back. Two hours later, severe weakness of both hands developed abruptly. Over the next 8 hours, severe paraparesis and urinary retention developed, with inability to lift legs against gravity, and she reported a T1 sensory level. Review of the outside magnetic resonance imaging noted key imaging findings, including initially normal magnetic resonance imaging within the first 12 hours of symptom presentation, and subsequent magnetic resonance imaging on day 3 showing anterior pencil-like hyperintensity on sagittal view and anterior U- or V-shaped pattern on axial view (termed U/V pattern), without associated gadolinium enhancement. Diffusion-weighted imaging was not obtained. Given the rapid, severe deficits with pain, spinal cord infarction was considered most likely, and the magnetic resonance imaging findings were typical. Magnetic resonance angiography of the neck with T1-fat-saturated views was obtained and did not show dissection. Laboratory evaluation showed a low-density lipoprotein value of 124 mg/dL and hemoglobin A1c of 6.2%. The patient was diagnosed with probable spontaneous spinal cord infarction on the basis of diagnostic criteria. The patient was counselled on smoking cessation, started on an aspirin and statin regimen, and followed up by a primary care provider for management of vascular risk factors. Residual neuropathic pain was treated with high doses of gabapentin. Importantly, unnecessary additional immunotherapy was avoided by establishing the correct diagnosis. Spontaneous spinal cord infarctions are an underrecognized cause of acute myelopathy. Spinal cord infarctions generally occur in older persons, with most cases associated with typical vascular risk factors, arterial dissection, and fibrocartilaginous embolism; historically, cases were often secondary to syphilis.
A 25-Year-Old Man With Recurrent Back Pain and Rapid-Onset Paraplegia
Authors: Zalewski Nicholas L.
Published: November 2021

A 25-year-old man was transferred for evaluation and management of severe transverse myelitis. He had no pertinent past medical history. His symptoms started approximately 6 months earlier with new, substantial low back pain for 2 days, followed by a 3-day history of lower extremity weakness. He could only ambulate with the help of a rolling chair and had to discontinue work because of the severity of the weakness, but his symptoms resolved spontaneously within a few days. Findings of repeated spinal cord magnetic resonance imaging were consistent with evolution of a recent hemorrhage in the lower thoracic spinal cord. Digital subtraction angiography of the spinal canal showed normal findings, without evidence of arteriovenous malformation. Additional thorough evaluations for bleeding diatheses, drugs of abuse, thorough skin evaluation to exclude melanoma, and systemic imaging with computed tomography of the chest, abdomen, and pelvis and testicular ultrasonography were all normal. Given the clinical timeline, the lobulated hemorrhagic appearance of the lesion with a surrounding T2-hypointense rim and heterogeneous T1 and T2 signal indicating recent hemorrhage, no pattern on imaging to suggest a neoplasm, with negative systemic evaluation and normal digital subtraction angiography, a diagnosis of hematomyelia due to intramedullary spinal cavernous malformation was made. No neurosurgical management was recommended given the complete cross-sectional spinal cord injury at the level of hemorrhage, with potential risk of surgery with resection of the intramedullary spinal cavernous malformation. Short-interval follow-up imaging 3 weeks later showed expected evolution of the recent hemorrhage secondary to intramedullary spinal cavernous malformation. Hematomyelia may be caused by several potential mechanisms. The most common nontraumatic causes are attributable to cavernous malformations and arteriovenous malformations. Hematomyelia most commonly presents with acute back pain referable to the site of hemorrhage and myelopathy deficits with a range of severity (often severe).
Progressive Myelopathy After Spine Surgery
Authors: McKeon Andrew , Zalewski Nicholas L.
Published: November 2021

A 69-year-old man with a progressive myelopathy for 2 years was referred for evaluation of suspected transverse myelitis. His medical history included discectomies, a severe episode of herpes simplex virus type 1 meningoencephalitis, and development of insidiously progressive numbness and weakness of his hands. Cervical spine magnetic resonance imaging showed 2 small, dural-based, gadolinium-enhancing lesions. Biopsy of these lesions showed only normal neural tissue. Subsequently, the dura was stripped away surgically from the lower cervical region, in an effort to remove these lesions. During the next year, a sensory level developed at about the level of the nipples (T4), along with a squeezing sensation on his trunk below. Imbalance and bilateral lower extremity weakness and numbness then developed. Magnetic resonance imaging showed a longitudinally extensive cord signal abnormality.

The cause of the patient’s initial subjective hand numbness and weakness was indeterminate. The onset of severely progressive symptoms after surgical removal of those lesions and the reported stripping of dura made it likely that the progressive cord edema was due to chronic adhesive arachnoiditis. His prior meningoencephalitis was a potential additional risk factor for arachnoiditis. Computed tomography myelography showed a markedly abnormal spinal canal with scalloping of the cord contour, with delayed flow of contrast above C6-C7, consistent with arachnoid adhesions causing obstruction of normal cerebrospinal fluid flow.

The patient was diagnosed with chronic adhesive arachnoiditis.

A C4-C7 laminectomy and surgical lysis of the cord meningeal adhesions was performed, with subsequent intensive neurorehabilitation. Follow-up spinal cord magnetic resonance imaging 6 months after surgery showed improvement of the T2-signal abnormality but persistent myelomalacia and spinal cord atrophy.

Adhesive arachnoiditis is an uncommon cause of progressive myelopathy resulting from an insult to the arachnoid meningeal layer, followed by inflammation and fibrosis. This process renders the arachnoid abnormally thick and adherent to the pia and dura mater. Abnormal adhesion of nerve roots or spinal cord to the dura produces neurologic impairment. Typical symptoms include back pain, paresthesias, lower limb weakness, and sensory loss. It is diagnosed clinically with supportive magnetic resonance imaging and computed tomography myelography findings.
Introduction
Authors: Holloway Debra
Published: November 2021

Women require contraceptive and reproductive/sexual health care from menarche to menopause. An holistic approach to care enables women of all ages to make effective and safe choices regarding contraceptive methods, managing sexually transmitted infections/human immuno–deficiency virus (STI/HIV), unplanned pregnancy care, or pregnancy care within the community and other specialist services provided by health professionals. The multidisciplinary team comprises: Consultants in Reproductive and Sexual Health), GPs, sessional doctors, nurse consultants, Clinical Nurse Specialist and Advanced Nurse Practitioners, nurses, midwives, health visitors, pharmacists, health advisors, associates, healthcare assistants, counsellors, client support workers (CSWs), and receptionists providing client-centred care.
Gynaecological oncology
Authors: Hughes Cathy
Published: November 2021

This chapter concerns cancers that affect the female reproductive organs, including the ovaries, fallopian tubes, uterus, cervix, vagina, and vulva. For each type of cancer the chapter covers the epidemiology, incidence, associated risk factors, presenting complaints, methods of diagnosis, grades and staging, and treatment. Where possible, monitoring procedures for prevention are explained. The chapter also includes an overview of radiotherapy, including dose and duration and treatment planning. Indications for chemotherapy for specific cancers are also covered.
Fertility and subfertility
Authors: Denga Alice
Published: November 2021

This chapter covers issues related to fertility and subfertility. It starts with lifestyle assessments that should be done as part of preconceptual care, and explains the psychological effects and counselling for subfertility alongside both male and female factors that affect difficulties in conceiving. Tests and investigations are covered for both partners, and the role of the fertility nurse specialist is defined. Ovulation induction, assisted conception, inter-uterine insemination, and IVF are all described. Pre-implantation genetic diagnosis is given a brief overview, and the chapter also explores adoption and surrogacy. Fertility preservation and the role of the Human Fertilization and Embryology Authority are covered.
Pituitary
Authors: Karavitaki Niki , Thompson Chris , Galloway Iona
Published: November 2021

This chapter covers the pituitary gland. It starts with the anatomy and physiology, then moves on to imaging, and pituitary function. It then covers common tests, including ITT, glucagon, ACTH stimulation, arginine, clomiphene, hCG, and TRH. It then begins to cover disorders of pituitary function, with treatment, hormone replacement, and investigation all included. Pituitary tumours are described, along with investigation, diagnosis, and treatment. Other disorders, including Cushing’s disease, cysts, inflammatory conditions are all included. Complications from other conditions are also described.
Endocrinology in pregnancy
Authors: Williamson Catherine , Scott Rebecca
Published: November 2021

This chapter covers both the normal and abnormal changes to the endocrine system during pregnancy. It begins with the thyroid in pregnancy, covering maternal hyperthyroidism, hyperemesis gravidarum, overt and subclinical maternal hypothyroidism, post-partum thyroid dysfunction, and fetal thyroid diseases owing to maternal thyroid disorders. Calcium metabolism, thyroid cancer, hypoparathyroidism, and lactation associated osteoporosis. Secondly, the pituitary gland in pregnancy is focused on, covering prolactinoma, Cushing’s Syndrome, acromegaly, non-functioning pituitary adenoma, hypopituitarism, and Diabetes Insipidus. Pre-existing adrenal disorders during pregnancy and alterations to management are also included.
Inherited endocrine syndromes and MEN
Authors: Newey Paul
Published: November 2021

This chapter begins with genetic testing for monogenic endocrine disorders, and then goes on to define the diagnosis, treatment, and management of McCune-Albright syndrome, neurofibromatosis, von Hippel-Lindau disease, Carney complex, Cowden syndrome, and POEMS syndrome. It then goes on to the clinical features and management of MEN type 1 and MEN type 2, and MEN type 4. Inherited primary hyperparathyroidism, phaeochromocytoma-paraganglioma syndromes, and renal calculi.
At-risk populations
Authors: Kennedy Nicholas , Reeve Katherine , Fontaine Elizabeth , White Stuart , Mawer Rebecca , Lomas Alexander
Published: November 2021

This chapter focuses on those vulnerable patient groups who carry high perioperative risk and need special perioperative consideration, such as those with obesity, malnourished patients, older patients, and patients with learning disabilities and/or autism.
Airway assessment and management
Authors: Cranshaw Jules , Kursumovic Emira , Cook Tim
Published: November 2021

This chapter provides detailed, practical and up-to-date information on management of the airway. It demystifies airway terminology, outlines airway assessment, and describes the management of the unanticipated difficult airway in adults. It includes a new section on intubating critically ill patients using the vortex approach, and outlines the equipment and techniques used to aid airway management. It gives practical information on the emergency front of neck airway and strategies to approach the obstructed airway. It explains rapid sequence induction, inhalational induction, awake tracheal intubation, and extubation after difficult intubation. It contains new sections on apnoeic oxygenation and how to manage patients with airborne respiratory viruses.
Cardiac anaesthesia
Authors: Byrne Kelly , Goldstone Kate , Simmons Peter
Published: November 2021

This chapter discusses the anaesthetic management of cardiac surgery. It begins with preoperative considerations, risk scoring for cardiac surgery, transoesophageal echocardiography and cardiopulmonary bypass (CPB). Surgical procedures covered include coronary artery bypass grafting (CABG) (including emergency and redo CABG); valve replacements and thoracic aortic surgery. Intraaortic balloon pumps and pulmonary hypertension are also covered.
Vascular surgery
Authors: Stoneham Mark
Published: November 2021

This chapter discusses the anaesthetic management of vascular surgery. It begins with general principles of the anaesthetic management of vascular surgical patients. Surgical procedures covered include abdominal aortic aneurysm (AAA) repair (including emergency and endovascular AAA repair and thoraco-abdominal aortic aneurysm repair; carotid endarterectomy; peripheral revascularisation operations; axillobifemoral bypass; amputations; thoracoscopic sympathectomy; first rib resection, arteriovenous fistula formation and varicose vein surgery.
Anaesthesia for radiology and cardiology
Authors: Wickham Alex , Holmes Katherine , Dunlop Craig , Tomlinson David
Published: November 2021

This chapter discusses the anaesthetic management of patients for CT or MRI scanning or interventional radiology procedures. It describes the particular hazards associated with the CT and MRI scanning rooms and recommends appropriate anaesthetic techniques. Interventional radiology procedures may include angioplasty; stenting; embolisation; chemotherapy; radiofrequency ablation; cryoablation; thrombolysis, transjugular intrahepatic portosystemic shunt (TIPSS), fluid aspiration, biopsies, percutaneous drain placement and vertebroplasty or cementoplasty. Anaesthesia for cardiology procedures is discussed, including cardioversion, angiography, cardiac device insertion and removal, electrophysiology procedures, and transcatheter aortic valve implantation (TAVI).
Obstetric anaesthesia and analgesia
Authors: Eldridge James , Cox Nicola , Allana Alisha , Lightfoot Heidi
Published: November 2021

This chapter discusses the anaesthetic management of the pregnant patient, for labour analgesia as well as surgical intervention. It begins with a description of the physiological and pharmacological changes of pregnancy. It describes methods of labour analgesia, including remifentanil, and epidural analgesia and its complications, such as post dural puncture headache (PDPH). It describes anaesthesia for Caesarean section (both regional and general); failed intubation; antacid prophylaxis; postoperative analgesia; retained placenta; in utero fetal death; hypertensive disease of pregnancy (pre-eclampsia, eclampsia and the hypertension, elevated liver enzymes and low platelets (HELLP) syndrome); massive obstetric haemorrhage; placenta praevia and morbidly adherent placenta (placenta accreta, increta and percreta); amniotic fluid embolism (AFE); maternal sepsis, and maternal resuscitation. It discusses comorbidity in pregnancy such as obesity and cardiac disease, and the patient who requires non-obstetric surgery while pregnant. It provides information on safe prescribing in pregnancy and breast-feeding.
Regional anaesthesia
Authors: Fairley Mark
Published: November 2021

This chapter discusses the techniques of regional anaesthesia and analgesia. It begins with an overview of regional anaesthesia and goes on to describe safe practice, and local anaesthetic agents. Techniques of locating nerves are then discussed, including ultrasound, and needle design is explored. Nerve blocks of the neck; upper limb; trunk; lower limb, and the neuraxis (spine) are described. Coagulation disorders, nerve injury and the management of local anaesthetic toxicity are discussed. The chapter concludes with a dermatome map and tables of recommended nerve blocks for particular operations.
Daily variability at milli-arcsecond scales in the radio-quiet NLSy1 Mrk 110
Authors: Panessa Francesca , Pérez-Torres Miguel , Hernández-García Lorena , Casella Piergiorgio , Giroletti Marcello , Orienti Monica , Baldi Ranieri D , Bassani Loredana , Fiocchi Maria Teresa , La Franca Fabio , Malizia Angela , McHardy Ian , Nicastro Fabrizio , Piro Luigi , Vincentelli Federico , Williams David R A , Ubertini Pietro
Published: November 2021

The origin of radio emission in the majority of active galactic nuclei is still poorly understood. Various competing mechanisms are likely involved in the production of radio emission and precise diagnostic tools are needed to disentangle them, of which variability is among the most powerful. For the first time, we show evidence for significant radio variability at 5 GHz at milli-arcsecond scales on days to weeks time-scales in the highly accreting and extremely radio-quiet (RQ) Narrow Line Seyfert 1 (NLSy1) Mrk 110. The simultaneous Swift/XRT light curve indicates stronger soft than hard X-ray variability. The short-term radio variability suggests that the GHz emitting region has a size smaller than ∼180 Schwarzschild radii. The high brightness temperature and the radio and X-ray variability rule out a star-formation and a disc wind origin. Synchrotron emission from a low-power jet and/or an outflowing corona is then favoured.
Realistic energy deposition and temperature heating in molecular clouds due to cosmic rays: a computation simulation with the GEANT4 code employing light particles and medium-mass and heavy ions
Authors: Pilling Sergio , Pazianotto Maurício Tizziani , de Souza Lucas Alves , Maciel do Nascimento Larissa
Published: November 2021

In the interstellar medium, Galactic and extragalactic cosmic rays (CRs) penetrate deeper in the molecular clouds (MCs) and promote inside several physical and physicochemical changes due to the energy deposition, including gas and grain heating, and triggering also molecular destruction and formation. In this work, in an attempt to simulate, in a more realistic way, the energy delivered by CRs in a typical MC (mass ∼5400 M☉ and size ∼106 au; mainly composed of H atoms), we combine the energy deposition of light particles and heavy ions, with the new calculations considering the medium-mass ions (3 ≤ Z ≤ 11). To execute the calculation, the Monte Carlo toolkit GEANT4 was applied to get the energy deposition rate per mass from many kinds of secondary particles, used in nuclear and hadron physics. The energy deposition by its induced cascade shower within the MC was characterized, as well as the relative energy deposition for all members of the medium-mass group. The results show that the incoming protons are the dominant source in the energy deposition and heating of the cloud, followed by alphas and electrons, with the medium-mass-ion and heavy-ion groups each contributing roughly 8 per cent. The current model also shows a temperature enhancement of up to 10 per cent in the external layers of the cloud (reaching 22.5 K) with respect to the previous calculations where only light particles were considered. However, neither heavy nor medium-mass ions contribute to the temperature enhancement in the deep core of the cloud.
Magnetic field strengths of the synchrotron self-absorption region in the jet of CTA 102 during radio flares
Authors: Kim Sang-Hyun , Lee Sang-Sung , Lee Jee Won , Hodgson Jeffrey A , Kang Sincheol , Algaba Juan-Carlos , Kim Jae-Young , Hodges Mark , Agudo Ivan , Fuentes Antonio , Escudero Juan , Myserlis Ioannis , Traianou Efthalia , Lähteenmäki Anne , Tornikoski Merja , Tammi Joni , Ramakrishnan Venkatessh , Järvelä Emilia
Published: November 2021

CTA 102 is a blazar implying that its relativistic jet points towards Earth and emits synchrotron radiation produced by energetic particles gyrating in the magnetic field. This study aims to figure out the physical origins of radio flares in the jet, including the connection between the magnetic field and the radio flares. The data set in the range of 2.6–343.5 GHz was collected over a period of ∼5.5 yr (2012 November 20–2018 September 23). During the data collection period, seven flares at 15 GHz with a range of the variability time-scale of roughly 76–227 d were detected. The quasi-simultaneous radio data were used to investigate the synchrotron spectrum of the source. We found that the synchrotron radiation is self-absorbed. The turnover frequency and the peak flux density of the synchrotron self-absorption (SSA) spectra are in the ranges of ∼42–172 GHz and ∼0.9–10.2 Jy, respectively. From the SSA spectra, we derived the SSA magnetic field strengths to be ∼9.20, ∼12.28, and ∼50.97 mG on 2013 December 24, 2014 February 28, and 2018 January 13, respectively. We also derived the equipartition magnetic field strengths to be in the range of ∼24–109 mG. The equipartition magnetic field strengths are larger than the SSA magnetic field strengths in most cases, which indicates that particle energy mainly dominates in the jet. Our results suggest that the flares in the jet of CTA 102 originated due to particle acceleration. We propose the possible mechanisms of particle acceleration.
The protoplanetary disc around HD 169142: circumstellar or circumbinary?
Authors: Poblete P P , Cuello N , Pérez S , Marino S , Calcino J , Macías E , Ribas Á , Zurlo A , Cuadra J , Montesinos M , Zúñiga-Fernández S , Bayo A , Pinte C , Ménard F , Price D J
Published: November 2021

Stellar binaries represent a substantial fraction of stellar systems, especially among young stellar objects. Accordingly, binaries play an important role in setting the architecture of a large number of protoplanetary discs. Binaries in coplanar and polar orientations with respect to the circumbinary disc are stable configurations and could induce non-axisymmetric structures in the dust and gas distributions. In this work, we suggest that the structures shown in the central region of the protoplanetary disc HD 169142 are produced by the presence of an inner stellar binary and a circumbinary (P-type) planet. We find that a companion with a mass ratio of 0.1, semimajor axis of 9.9 au, eccentricity of 0.2, and inclination of 90°, together with a 2 MJ coplanar planet on a circular orbit at 45 au reproduce the structures at the innermost ring observed at 1.3 mm and the shape of spiral features in scattered light observations. The model predicts changes in the disc’s dust structure, and star’s astrometric parameters, which would allow testing its veracity by monitoring this system over the next 20 yr.
Statistical search for angular non-stationarities of long gamma-ray burst jets using Swift data
Authors: Budai A , Raffai P , Borgulya B , Dawes B A , Szeifert G
Published: November 2021

In a previous article, we argued that angular non-stationarities of gamma-ray burst (GRB) jets can result in a statistical connection between the angle values deduced from jet break times and the variabilities of prompt light curves. The connection should be an anticorrelation if luminosity densities of jets follow a power-law or a uniform profile, and a correlation if they have a Gaussian profile. In this follow-up paper, we search for the connection by measuring Spearman’s rank correlation coefficient in a sample of 19 long GRBs observed by the Swift satellite. Using 16 of the GRBs with well-defined angle measurements, we find $\rho = -0.38_{-0.1}^{+0.1}$ and $p = 0.15_{-0.09}^{+0.14}$. Adding three more GRBs to the sample, each with a pair of equally possible angle values, can strengthen the anticorrelation to $\rho =-0.46_{-0.08}^{+0.09}$ and $p=0.05_{-0.03}^{+0.07}$. We show that these results are incompatible with non-stationary jets having Gaussian profiles, and that ≳100 GRBs with observed afterglows would be needed to confirm the potential existence of the angle-variability anticorrelation with 3σ significance. If the connection is real, GRB jet angles would be constrainable from prompt gamma light curves, without the need of afterglow observations.
Constraining the neutrino mass using a multitracer combination of two galaxy surveys and cosmic microwave background lensing
Authors: Ballardini Mario , Maartens Roy
Published: November 2021

Measuring the total neutrino mass is one of the most exciting opportunities available with next-generation cosmological data sets. We study the possibility of detecting the total neutrino mass using large-scale clustering in 21 cm intensity mapping and photometric galaxy surveys, together with cosmic microwave background (CMB) information. We include the scale-dependent halo bias contribution due to the presence of massive neutrinos, and use a multitracer analysis in order to reduce cosmic variance. The multitracer combination of an SKAO-MID 21 cm intensity map with stage 4 CMB dramatically shrinks the uncertainty on total neutrino mass to $\sigma (M_\nu) \simeq 45\,$ meV, using only linear clustering information ($k_{\rm max} = 0.1\, h\, \mathrm{Mpc}^{-1}$) and without a prior on optical depth. When we add to the multitracer the clustering information expected from Legacy Survey of Space and Time, the forecast is $\sigma (M_\nu) \simeq 12\,$ meV.
Comet fragmentation as a source of the zodiacal cloud
Authors: Rigley Jessica K , Wyatt Mark C
Published: November 2021

Models of the zodiacal cloud’s thermal emission and sporadic meteoroids suggest Jupiter-family comets (JFCs) as the dominant source of interplanetary dust. However, comet sublimation is insufficient to sustain the quantity of dust presently in the inner Solar system, suggesting that spontaneous disruptions of JFCs may supply the zodiacal cloud. We present a model for the dust produced in comet fragmentations and its evolution. Using results from dynamical simulations, the model follows individual comets drawn from a size distribution as they evolve and undergo recurrent splitting events. The resulting dust is followed with a kinetic model which accounts for the effects of collisional evolution, Poynting–Robertson drag, and radiation pressure. This allows to model the evolution of both the size distribution and radial profile of dust, and we demonstrate the importance of including collisions (both as a source and sink of dust) in zodiacal cloud models. With physically motivated free parameters this model provides a good fit to zodiacal cloud observables, supporting comet fragmentation as the plausibly dominant dust source. The model implies that dust in the present zodiacal cloud likely originated primarily from disruptions of ∼50-km comets, since larger comets are ejected before losing all their mass. Thus much of the dust seen today was likely deposited as larger grains ∼0.1 Myr in the past. The model also finds the dust level to vary stochastically; e.g. every ∼50 Myr large (>100 km) comets with long dynamical lifetimes inside Jupiter cause dust spikes with order of magnitude increases in zodiacal light brightness lasting ∼1 Myr. If exozodiacal dust is cometary in origin, our model suggests it should be similarly variable.
Multiple Novel Traits without Immediate Benefits Originate in Bacteria Evolving on Single Antibiotics
Authors: Karve Shraddha , Wagner Andreas
Published: November 2021

How new traits originate in evolution is a fundamental question of evolutionary biology. When such traits arise, they can either be immediately beneficial in their environment of origin, or they may become beneficial only in a future environment. Compared to immediately beneficial novel traits, novel traits without immediate benefits remain poorly studied. Here we use experimental evolution to study novel traits that are not immediately beneficial but that allow bacteria to survive in new environments. Specifically, we evolved multiple E. coli populations in five antibiotics with different mechanisms of action, and then determined their ability to grow in more than 200 environments that are different from the environment in which they evolved. Our populations evolved viability in multiple environments that contain not just clinically relevant antibiotics, but a broad range of antimicrobial molecules, such as surfactants, organic and inorganic salts, nucleotide analogues and pyridine derivatives. Genome sequencing of multiple evolved clones shows that pleiotropic mutations are important for the origin of these novel traits. Our experiments, which lasted fewer than 250 generations, demonstrate that evolution can readily create an enormous reservoir of latent traits in microbial populations. These traits can facilitate adaptive evolution in a changing world.
The Imperial Arts
Authors: Anderson Benjamin
Published: November 2021

Images of Byzantine emperors served not only to glorify those depicted, but also as media through which subjects articulated their relationships both to individual sovereigns and to the state. The predominant materials, compositional strategies, and social dynamics that constrained such expressions changed substantially over the course of Byzantine history. After the Late Antique system of dedicating monumental bronze statues collapsed in the seventh century, a more flexible set of practices emerged, whose primary expressions were two-dimensional schemata. In the last empire’s last centuries, diplomatic considerations encouraged the production of scenic tableaux, while the closed series of portraits predominated after 1453. The transactional nature of imperial portraiture, the distinction between individual and office, and the representation of emperors as subjects of historical knowledge will repay further research.
Armenia
Authors: Maranci Christina
Published: November 2021

A study of medieval Armenian painting, church architecture, bas-relief sculpture, and other media demonstrates close attention to, and reception of, the art and culture of the Byzantine Empire. Historic Armenia (including the present-day Armenian Republic and territories in eastern Anatolia, southern Georgia, northwest Iran, and Azerbaijan) and the Armenian kingdom of Cilicia (1199–1375, southwestern Anatolia) had close relations with neighboring powers throughout the medieval era, and scholars, most prominently Sirarpie Der Nersessian, have long studied the presence of Byzantine ideas in Armenian art and architecture. The early medieval period, the “Age of the Kingdoms” (ninth to eleventh centuries), and twelfth- to fourteenth-century Cilicia demonstrate strong evidence for contact and familiarity with Byzantine culture. An examination of select cases demonstrates the diverse and dynamic nature of such appropriations, reflecting the complex and changing nature of political, social, religious, and cultural relations between empire and locality.
The Origin of Icons
Authors: Mathews Thomas F.
Published: November 2021

The origin of icons, and by extension of Christian painting, can now be traced to the panel painting tradition of pagan divinities in wide use in Late Antiquity throughout the Mediterranean. Both pagan and Christian panel paintings were employed as votive or thank offerings. According to an ancient phenomenon known as “syncretism,” emperors were identified with gods and Greek gods with Egyptian ones. Triptych paintings were a new way of exploring the implications of syncretism. In the sixth century, icons went from being single offerings to an assembly on the templon barrier. The earliest surviving evidence of church iconography, decoration and ritual cult, or liturgy, comes from Constantinople, at the churches of St. Polyeuktos and Hagia Sophia.
Bronze and Copper Icons
Authors: Schwartz Ellen C.
Published: November 2021

Byzantine copper alloy icons were created by repoussé and casting. The repoussé group varies in size and were used as individual icons and decoration for liturgical furniture and lintels. They imitate precious metal icons, occasionally plated to look like silver or with imitation gems in their frames. Cast icons, smaller and heavier, probably served as portable icons or magic tokens; some might have been used as dies or mold matrices. In iconography, inscriptions, and style, copper icons imitate contemporary pieces in other media. Most feature single figures; fewer display scenes. Varying from elegant to crude, they could be made affordable by molds, stamps, or dies. More study of the cast pieces, along with other bronze items, remains to be done.
Illuminated Manuscripts: Religious
Authors: McCombs Susan Madigan
Published: November 2021

Most illustrated Byzantine religious manuscripts—books of the Old and New Testament, sermons, psalters and hours, lectionaries, saints’ lives, and hymnals—were deluxe hand-produced books made in the capital primarily as gifts or for use in the performance of the liturgy or other religious ceremony. Surviving examples reflect co-existing phenomena including an interest in texts collected in one luxuriously ornamented volume; the popularity of certain religious texts (or authors) in a given time and place; the notion that books made of expensive materials paid homage to the giver, the owner, and the author of the texts within; and prestige associated with owning or giving a volume created by artists and scribes working in the most sought-after styles of the day.
Illuminated Manuscripts: Secular
Authors: Havice Christine
Published: November 2021

Illuminated manuscripts with non-religious content—texts on literature, medicine, science, warfare, geography, hunting, and history—typically derive from illuminated Classical and Late Antique texts. Over time, the direct, explicatory images accrued additional features and sometimes transformed into full miniatures with settings and humans performing actions or demonstrating effects. Artists relied mostly on convention and formulae but can be occasionally glimpsed responding to the necessity of producing an original image. As with religious books, secular programs can be analyzed to discern particular agendas, usually of commissioners or intended recipients, while the books themselves had practical application—instructions on building a siege machine or what plant not to consume—as well as serving as luxury products for reading, presentation, even performance.