Case 321: Leigh Syndrome.

HISTORY: A 9-month-old preterm male infant born at 33 weeks gestation presented with a 2-month history of developmental decline. The parents reported that over the past several months, they noted regression of milestones, where the infant stopped smiling, crying, expressing himself, or making eye contact. The parents also reported that the infant had multiple seizures during which he would wake up stiff and stare into space for 10-20 seconds while his lips would become blue. The parents were referred to a neurologist, where physical examination was notable for hypotonia. Electroencephalography (EEG) revealed frequent bilateral parietal epileptiform discharges. The patient was subsequently started on lacosamide. The patient's medical history was notable for abnormally low citrulline levels at birth, with negative results of urea cycle disorder testing at the time, along with left inguinal hernia repair performed 3 months ago. More recent laboratory analysis had shown persistently elevated serum lactate and alanine levels. There was no history of travel, recent infection, or vaccine administration. MRI of the brain with spectroscopy was performed for further evaluation.

Case 321.

HISTORY: A 9-month-old preterm male infant born at 33 weeks gestation presented with a 2-month history of developmental decline. The parents reported that over the past several months, they noted regression of milestones, where the infant stopped smiling, crying, expressing himself, or making eye contact. The parents also reported that the infant had multiple seizures during which he would wake up stiff and stare into space for 10-20 seconds while his lips would become blue. The parents were referred to a neurologist, where physical examination was notable for hypotonia. Electroencephalography (EEG) revealed frequent bilateral parietal epileptiform discharges. The patient was subsequently started on lacosamide. The patient's medical history was notable for abnormally low citrulline levels at birth, with negative results of urea cycle disorder testing at the time, along with left inguinal hernia repair performed 3 months ago. More recent laboratory analysis had shown persistently elevated serum lactate and alanine levels. There was no history of travel, recent infection, or vaccine administration. MRI of the brain with spectroscopy was performed for further evaluation (Figs 1-6).

Predictive modelling using neuroimaging data in the presence of confounds.

When training predictive models from neuroimaging data, we typically have available non-imaging variables such as age and gender that affect the imaging data but which we may be uninterested in from a clinical perspective. Such variables are commonly referred to as 'confounds'. In this work, we firstly give a working definition for confound in the context of training predictive models from samples of neuroimaging data. We define a confound as a variable which affects the imaging data and has an association with the target variable in the sample that differs from that in the population-of-interest, i.e., the population over which we intend to apply the estimated predictive model. The focus of this paper is the scenario in which the confound and target variable are independent in the population-of-interest, but the training sample is biased due to a sample association between the target and confound. We then discuss standard approaches for dealing with confounds in predictive modelling such as image adjustment and including the confound as a predictor, before deriving and motivating an Instance Weighting scheme that attempts to account for confounds by focusing model training so that it is optimal for the population-of-interest. We evaluate the standard approaches and Instance Weighting in two regression problems with neuroimaging data in which we train models in the presence of confounding, and predict samples that are representative of the population-of-interest. For comparison, these models are also evaluated when there is no confounding present. In the first experiment we predict the MMSE score using structural MRI from the ADNI database with gender as the confound, while in the second we predict age using structural MRI from the IXI database with acquisition site as the confound. Considered over both datasets we find that none of the methods for dealing with confounding gives more accurate predictions than a baseline model which ignores confounding, although including the confound as a predictor gives models that are less accurate than the baseline model. We do find, however, that different methods appear to focus their predictions on specific subsets of the population-of-interest, and that predictive accuracy is greater when there is no confounding present. We conclude with a discussion comparing the advantages and disadvantages of each approach, and the implications of our evaluation for building predictive models that can be used in clinical practice.

Decoding negative affect personality trait from patterns of brain activation to threat stimuli.

INTRODUCTION: Pattern recognition analysis (PRA) applied to functional magnetic resonance imaging (fMRI) has been used to decode cognitive processes and identify possible biomarkers for mental illness. In the present study, we investigated whether the positive affect (PA) or negative affect (NA) personality traits could be decoded from patterns of brain activation in response to a human threat using a healthy sample. METHODS: fMRI data from 34 volunteers (15 women) were acquired during a simple motor task while the volunteers viewed a set of threat stimuli that were directed either toward them or away from them and matched neutral pictures. For each participant, contrast images from a General Linear Model (GLM) between the threat versus neutral stimuli defined the spatial patterns used as input to the regression model. We applied a multiple kernel learning (MKL) regression combining information from different brain regions hierarchically in a whole brain model to decode the NA and PA from patterns of brain activation in response to threat stimuli. RESULTS: The MKL model was able to decode NA but not PA from the contrast images between threat stimuli directed away versus neutral with a significance above chance. The correlation and the mean squared error (MSE) between predicted and actual NA were 0.52 (p-value=0.01) and 24.43 (p-value=0.01), respectively. The MKL pattern regression model identified a network with 37 regions that contributed to the predictions. Some of the regions were related to perception (e.g., occipital and temporal regions) while others were related to emotional evaluation (e.g., caudate and prefrontal regions). CONCLUSION: These results suggest that there was an interaction between the individuals' NA and the brain response to the threat stimuli directed away, which enabled the MKL model to decode NA from the brain patterns. To our knowledge, this is the first evidence that PRA can be used to decode a personality trait from patterns of brain activation during emotional contexts.

Advanced imaging techniques in pediatric body MRI.

While there are many challenges specific to pediatric abdomino-pelvic MRI, many recent advances are addressing these challenges. It is therefore essential for radiologists to be familiar with the latest advances in MR imaging. Laudable efforts have also recently been implemented in many centers to improve the overall experience of pediatric patients, including the use of dedicated radiology child life specialists, MRI video goggles, and improved MR suite environments. These efforts have allowed a larger number of children to be scanned while awake, with fewer studies being done under sedation or anesthesia; this has resulted in additional challenges from patient motion and difficulties with breath-holding and tolerating longer scan times. In this review, we highlight common challenges faced in imaging the pediatric abdomen and pelvis and discuss the application of the newest techniques to address these challenges. Additionally, we highlight the newest advances in quantified imaging techniques, specifically in MR liver iron quantification. The techniques described in this review are all commercially available and can be readily implemented.

Pre-procedural scout radiographs are unnecessary for routine pediatric fluoroscopic examinations.

BACKGROUND: Although practice patterns vary, scout radiographs are often routinely performed with pediatric fluoroscopic studies. However few studies have evaluated their utility in routine pediatric fluoroscopy. OBJECTIVE: To evaluate the value of scout abdomen radiographs in routine barium or water-soluble enema, upper gastrointestinal (GI) series, and voiding cystourethrogram pediatric fluoroscopic procedures. MATERIALS AND METHODS: We retrospectively evaluated 723 barium or water-soluble enema, upper GI series, and voiding cystourethrogram fluoroscopic procedures performed at our institution. We assessed patient history and demographics, clinical indication for the examination, prior imaging findings and impressions, scout radiograph findings, additional findings provided by the scout radiograph that were previously unknown, and whether the scout radiograph contributed any findings that significantly changed management. RESULTS: We retrospectively evaluated 723 fluoroscopic studies (368 males and 355 females) in pediatric patients. Of these, 700 (96.8%) had a preliminary scout radiograph. Twenty-three (3.2%) had a same-day radiograph substituted as a scout radiograph. Preliminary scout abdomen radiographs/same-day radiographs showed no new significant findings in 719 (99.4%) studies. New but clinically insignificant findings were seen in 4 (0.6%) studies and included umbilical hernia, inguinal hernia and hip dysplasia. No findings were found on the scout radiographs that would either alter the examination performed or change management with regard to the exam. CONCLUSION: Pre-procedural scout abdomen radiographs are unnecessary in routine barium and water-soluble enema, upper GI series, and voiding cystourethrogram pediatric fluoroscopic procedures and can be substituted with a spot fluoroscopic last-image hold.

Gadolinium-based contrast agents in pediatric magnetic resonance imaging.

Gadolinium-based contrast agents can increase the accuracy and expediency of an MRI examination. However the benefits of a contrast-enhanced scan must be carefully weighed against the well-documented risks associated with administration of exogenous contrast media. The purpose of this review is to discuss commercially available gadolinium-based contrast agents (GBCAs) in the context of pediatric radiology. We discuss the chemistry, regulatory status, safety and clinical applications, with particular emphasis on imaging of the blood vessels, heart, hepatobiliary tree and central nervous system. We also discuss non-GBCA MRI contrast agents that are less frequently used or not commercially available.

Radiation exposure contribution of the scout abdomen radiograph in common pediatric fluoroscopic procedures.

BACKGROUND: Contrast enema, voiding cystourethrography and upper gastrointestinal studies are the most common fluoroscopic procedures in children. Scout abdomen radiographs have been routinely obtained prior to fluoroscopy and add to the radiation exposure from these procedures. Elimination of unnecessary routine scout radiographs in select studies might significantly reduce radiation exposure to children and improve the overall benefit-to-risk ratio of these fluoroscopic procedures. OBJECTIVE: To determine the radiation exposure contribution of the preliminary/scout abdomen radiographs with respect to the radiation exposure of the total procedure. MATERIALS AND METHODS: We retrospectively collected demographic information and radiation exposure values of dose area product (in Gy-cm(2)) and entrance air kerma (in mGy) - initially for the scout abdomen radiographs done prior to fluoroscopy and subsequently the total procedural radiation values (the combined values of the scout radiograph and fluoroscopic radiation exposure) - in children who underwent contrast enemas, voiding cystourethrograms and upper gastrointestinal studies in a 4-month period. The radiation parameters, including fluoroscopy time, dose area product and entrance air kerma, were available in the log book maintained in the fluoroscopy suite. Fluoroscopy procedures were performed on a single fluoroscopy machine using four frames per second pulse rate and other radiation-minimizing techniques. Usage of the grid to obtain scout radiographs was also recorded. The proportion of radiation exposure from the scout radiograph relative to that of the total procedure was calculated by dividing the individual parameters of the scout to the total procedural values and multiplied by 100 to express these values as a percentage. We calculated mean, median and range and performed statistical analysis of the data. RESULTS: A total of 151 procedures performed on 71 males and 80 females qualified for the study. The age range of the patients was 2 days to 18 years, with a mean of nearly 3.5 years (40 months) and median of 15 months. There were 63 upper gastrointestinal studies, 65 voiding cystourethrography studies and 23 contrast enema studies. The fluoroscopy time for all procedures combined ranged from 0.1 min (6 s) to 2 min, with mean and median values of 0.4 min and 0.3 min, respectively. The fractional radiation exposure contribution for the dose area product of scout abdomen radiograph to the total procedure ranged from 4% to 98%, with mean and median values of 51% and 49%, respectively. The fractional contribution of the scout radiograph to the total procedure for the entrance air kerma values ranged from 6% to 97%, with mean and median values of 29% and 26%, respectively. There was a significant negative correlation (P<0.001) between fluoroscopy radiation time and the proportion of radiation parameters of scout radiograph to total procedural values. CONCLUSION: Scout radiographs can contribute a significant proportion (median values of approximately 50% for the dose area product and 26% for the entrance air kerma) of radiation exposure in common fluoroscopy procedures in children.

ECG-synchronized CT angiography in 324 consecutive pediatric patients: spectrum of indications and trends in radiation dose.

The aim of the study is to describe the spectrum of indications for pediatric ECG-synchronized CT angiography (CTA), the main determinants of radiation exposure, and trends in radiation dose over time at a single, tertiary referral center. The study was IRB approved and HIPAA compliant with informed consent waived. Between 2005 and 2013, 324 pediatric patients underwent ECG-synchronized CTA to evaluate known or suspected cardiovascular abnormalities (109 female, median age 8.1 years). The effective dose (ED) was calculated using age-specific correction factors. Univariate and multivariate regression analyses were performed to identify predictors of radiation dose. The most common primary indications for the CTA examinations included known or suspected coronary pathologies (n = 166), complex congenital heart disease (n = 73), and aortic pathologies (n = 41). Median radiation exposure decreased from 12 mSv for patients examined in the years 2005-2007 to 1.2 mSv for patients examined in the years 2011-2013 (p < 0.001). Patients scanned using a tube potential of 80 kV (n = 259) had a significantly lower median radiation dose (1.4 mSv) compared to patients who were scanned at 100 kV (n = 46, median 6.3 mSv) or 120 kV (n = 19, median 19 mSv, p < 0.001). Tube voltage, followed by tube current and the method of ECG-synchronization were the strongest independent predictors of radiation dose. Growing experience with dose-saving techniques and CTA protocols tailored to the pediatric population have led to a tenfold reduction in radiation dose over recent years and now allow routinely performing ECG-synchronized CTA in children with a radiation dose on the order of 1 mSv.

Brain microstructure reveals early abnormalities more than two years prior to clinical progression from mild cognitive impairment to Alzheimer's disease.

Diffusion imaging is a promising marker of microstructural damage in neurodegenerative disorders, but interpretation of its relationship with underlying neuropathology can be complex. Here, we examined both volumetric and brain microstructure abnormalities in 13 amnestic patients with mild cognitive impairment (MCI), who progressed to probable Alzheimer's disease (AD) no earlier than 2 years after baseline scanning, in order to focus on early, and hence more sensitive, imaging markers. We compared them to 22 stable amnestic MCI patients with similar cognitive performance and episodic memory impairment but who did not show progression of symptoms for at least 3 years. Significant group differences were mainly found in the volume and microstructure of the left hippocampus, while white matter group differences were also found in the body of the fornix, left fimbria, and superior longitudinal fasciculus (SLF). Diffusion index abnormalities in the SLF were the sign of a subtle microstructural injury not detected by standard atrophy measures in the corresponding gray matter regions. The microstructural measure obtained in the left hippocampus using diffusion imaging showed the most substantial differences between the two groups and was the best single predictor of future progression to AD. An optimal prediction model (91% accuracy, 85% sensitivity, 96% specificity) was obtained by combining MRI measures and CSF protein biomarkers. These results highlight the benefit of using the information of brain microstructural damage, in addition to traditional gray matter volume, to detect early, subtle abnormalities in MCI prior to clinical progression to probable AD and, in combination with CSF markers, to accurately predict such progression.

Performance of a multigene genomic classifier and clinical parameters in predicting malignancy in a Southeast Asian cohort of patients with cytologically indeterminate thyroid nodules.

BACKGROUND: Most thyroid nodules are benign. It is important to determine the likelihood of malignancy in such nodules to avoid unnecessary surgery. The primary objective of this study was to characterize the genetic landscape and the performance of a multigene genomic classifier in fine-needle aspiration (FNA) biopsies of cytologically indeterminate thyroid nodules in a Southeast Asian cohort. The secondary objective was to assess the predictive contribution of clinical characteristics to thyroid malignancy. METHODS: This prospective, multicenter, blinded study included 132 patients with 134 nodules. Molecular testing (MT) with ThyroSeq v3 was performed on clinical or ex-vivo FNA samples. Centralized pathology review also was performed. RESULTS: Of 134 nodules, consisting of 61% Bethesda category III, 20% category IV, and 19% category V cytology, and 56% were histologically malignant. ThyroSeq yielded negative results in 37.3% of all FNA samples and in 42% of Bethesda category III-IV cytology nodules. Most positive samples had RAS-like (41.7%), followed by BRAF-like (22.6%), and high-risk (17.9%) alterations. Compared with North American patients, the authors observed a higher proportion of RAS-like mutations, specifically NRAS, in Bethesda categories III and IV and more BRAF-like mutations in Bethesda category III. The test had sensitivity, specificity, negative predictive value, and positive predictive value of 89.6%, 73.7%, 84.0%, and 82.1%, respectively. The risk of malignancy was predicted by positive MT and high-suspicion ultrasound characteristics according to American Thyroid Association criteria. CONCLUSIONS: Even in the current Southeast Asian cohort with nodules that had a high pretest cancer probability, MT could lead to potential avoidance of diagnostic surgery in 42% of patients with Bethesda category III-IV nodules. MT positivity was a stronger predictor of malignancy than clinical parameters.

Pediatric Respiratory Emergencies-Recognition, Approach, and Management.

This article reviews the current trends and management of respiratory emergencies in children. Respiratory emergencies are a common report in pediatrics and often require prompt recognition and intervention. It is important to differentiate upper from lower respiratory disease processes because the management is often different. With the advent of many vaccinations, the concern for certain diseases has changed with variations in the prevalence of other organisms. This article discusses detection and management of many respiratory emergencies. [Pediatr Ann. 2023;52(4):e146-e152.].

Integrating High-Impact Practices (HIPs) In Medical Curriculum At Northern Border University: Strengths, Challenges, and Examples.

BACKGROUND: High-Impact Practices (HIPs) are educational practices that have been shown to increase rates of student retention, engagement, and persistence to graduation which help them to become high achievers and lifelong learners. Universities strongly encourage faculty members to incorporate one or more of these HIPs in order to improve active learning among students. Students are met with a variety of experiences that are not entirely of their choice, including expectations for academic performance, interactions with faculty, staff, and peers, and extracurricular activities that may or may not match their expectations and skills. Higher retention and high-grade achievement rates are attributed to HIPs. The mechanism by which HIPs improve retention is poorly understood. AIMS AND OBJECTIVES: There are numerous analyses of the objectives particular to undergraduate medical education in recent years. There have been proposed three major target categories. Undergraduate medical education has been positioned within a liberal education framework, where the main objective is to equip students with the critical thinking abilities, broad general education, and subject-specific knowledge they will need to be able to effectively problem-solve, adapt to new roles, and apply public health thinking and practices to a variety of situations. We tried to incorporate HIPs in a medical curriculum at the Faculty of Medicine, Northern Border University, by giving them topics that can be used to create public awareness about the selected objectives which may help the community greatly. METHODOLOGY: Students were asked to make posters or videos on the topics and were asked to write reflections about their experience and give feedback to the coordinators for improvements and to make these HIPs better so that they can be included uniformly in the other courses as well. RESULTS AND CONCLUSIONS: Based on results from a random sample of undergraduate students, we draw the conclusion that HIPs are correlated with engagement, which is the alignment of the student's critical thinking and ability to work in effective teams, group projects, learning communities, and sequence courses. HIPs have an impact on involvement among students across the world. HIPs are effective to the extent that they engage pupils, encouraging a greater commitment, which is one way to understand their success.

Laparoscopic Appendectomy Translates into Less Analgesics and Faster Return to Work in Asia.

Background: Laparoscopic appendectomy (LA) is claimed to require less analgesic and allow for a faster return to work. This study examines whether these benefits hold true in Asian patient populations. Methods: A retrospective audit of emergency appendectomies over one year was conducted to study outcomes of postoperative pain, length of stay (LOS), duration of analgesia, and hospitalization leave (HL). A telephone questionnaire evaluated post-discharge analgesic intake, residual symptoms at follow-up, adequacy of HL and opinion on teleconsult reviews. Results: Of the 201 patients, 187 (93%) underwent LA. Presurgery symptoms were significantly longer in the open appendectomy (OA) group (mean: OA 3.79, LA 1.81 days; p = 0.026) which also had a higher frequency of perforation (71.4%). LA patients reported less pain compared to OA (LA 3.60 vs. OA 4.14; p = 0.068) but were prescribed the same 2 weeks of analgesics as OA. LOS was significantly less for LA (mean LA 3.09, OA 6.93 days; p = 0.006). Mean HL for LA and OA were 17.9 and 21.8 days respectively (p = 0.05). Nearly 83% patients did not complete the prescribed course of analgesics and 47% patients felt that HL was more than adequate. Seventy-five percent of patients were asymptomatic at hospital follow-up and nearly 41% agreed to teleconsult reviews. Conclusion: Majority of LA patients do not need 2 weeks of analgesics and their HL can be shortened for faster return to work thereby realizing the true benefits of minimally invasive surgery. Selected cases can be offered postoperative teleconsultation.

DTI measures in crossing-fibre areas: increased diffusion anisotropy reveals early white matter alteration in MCI and mild Alzheimer's disease.

Though mild cognitive impairment is an intermediate clinical state between healthy aging and Alzheimer's disease (AD), there are very few whole-brain voxel-wise diffusion MRI studies directly comparing changes in healthy control, mild cognitive impairment (MCI) and AD subjects. Here we report whole-brain findings from a comprehensive study of diffusion tensor indices and probabilistic tractography obtained in a very large population of healthy controls, MCI and probable AD subjects. As expected from the literature, all diffusion indices converged to show that the cingulum bundle, the uncinate fasciculus, the entire corpus callosum and the superior longitudinal fasciculus are the most affected white matter tracts in AD. Significant differences between MCI and AD were essentially confined to the corpus callosum. More importantly, we introduce for the first time in a degenerative disorder an application of a recently developed tensor index, the "mode" of anisotropy, as well as probabilistic crossing-fibre tractography. The mode of anisotropy specifies the type of anisotropy as a continuous measure reflecting differences in shape of the diffusion tensor ranging from planar (e.g., in regions of crossing fibres from two fibre populations of similar density or regions of "kissing" fibres) to linear (e.g., in regions where one fibre population orientation predominates), while probabilistic crossing-fibre tractography allows to accurately trace pathways from a crossing-fibre region. Remarkably, when looking for whole-brain diffusion differences between MCI patients and healthy subjects, the only region with significant abnormalities was a region of crossing fibres in the centrum semiovale, showing an increased mode of anisotropy. The only white matter region demonstrating a significant difference in correlations between neuropsychological scores and a diffusion measure (mode of anisotropy) across the three groups was the same region of crossing fibres. Further examination using probabilistic tractography established explicitly and quantitatively that this previously unreported increase of mode and co-localised increase of fractional anisotropy was explained by a relative preservation of motor-related projection fibres (at this early stage of the disease) crossing the association fibres of the superior longitudinal fasciculus. These findings emphasise the benefit of looking at the more complex regions in which spared and affected pathways are crossing to detect very early alterations of the white matter that could not be detected in regions consisting of one fibre population only. Finally, the methods used in this study may have general applicability for other degenerative disorders and, beyond the clinical sphere, they could contribute to a better quantification and understanding of subtle effects generated by normal processes such as visuospatial attention or motor learning.

Preterm infant with subdural hematoma from malpositioned scalp intravenous catheter.

Vascular access is critical in the care of sick infants and children for the direct administration of medications and fluids. In infants, especially preterm infants, the use of scalp veins is a common practice because of less subcutaneous fat and less mobility around the catheter site decreasing the risk of dislodgement. We describe a case of a 24-week preterm infant girl born via caesarean section delivery who developed signs of increased intracranial pressure on day of life 11. A head computed tomography (CT) demonstrated large bilateral subdural hematomas with midline shift secondary to packed red blood cell infusion via an incorrectly positioned scalp intravenous catheter in the subdural space. In general, the use of scalp veins for intravenous access is a common method for direct administration of medications and fluids in small infants, with risks that are comparable to those associated with peripheral venous access. The use of scalp intravenous catheters is a fairly safe practice when correctly positioned. Position confirmation before and during use is vital to avoid potential intracranial complications.

A rare case of ectopic retrosternal goiter.

It is important for the clinician to be familiar with interpreting a variety of radiological modalities that provide vital information that will aid in the preoperative planning, counseling, and subsequent management of patients with retrosternal goiter.

Minimally invasive video-assisted thyroidectomy in Asian patients: experience from Singapore.

BACKGROUND: Minimally invasive video-assisted thyroidectomy (MIVAT) although well established in Europe has not yet gained widespread acceptance in Asia. We describe our learning experience in the first reported series of 105 cases from Singapore. METHODS: A retrospective analysis of outcomes in 105 patients who underwent MIVAT from April 2011 to 2018 was performed. The inclusion criteria were - symptomatic benign thyroid pathologies and follicular lesions or neoplasms needing a hemi-thyroidectomy. A thyroid lobe volume less than 35 mL was used as cut-off. Patients underwent surgeon-performed thyroid ultrasound with biopsy of solid nodules. All cases were operated by one surgeon using standard Miccoli technique with energy device used in all cases. RESULTS: From a total of 424 patients with nodular goitres undergoing thyroidectomy, 105 (24%) symptomatic eligible patients underwent the MIVAT procedure (M:F - 23:82). The mean incision lengths at start and completion were 1.7 cm (range 1.5-2 cm) and 2.4 cm (range 2-2.7 cm), respectively. Mean operating time was 97 min (range 59-160 min). There were four conversions (3.8%) in the first 25 cases and four patients (3.8%) experienced transient hoarseness with full recovery. Visual analogue pain scores at 6 and 24 h post-operatively were 2.7 and 1.1, respectively. Scar satisfaction was reported as excellent (75%), satisfactory (23%) and poor (2%). CONCLUSION: Although technically more demanding, MIVAT is a safe and useful operation in a thyroid surgeon's armamentarium. The limitation of goitre size, however, allows only a small percentage of symptomatic patients to undergo this procedure.

Evolution of a Dedicated Emergency Surgery and Trauma (ESAT) unit over 3 years: sustained improved outcomes.

INTRODUCTION: The traditional 24-h call model faces pressure from competing needs between emergency and elective services. Recognizing this, a dedicated ESAT service was developed in Khoo Teck Puat Hospital in Singapore, with improved clinical outcomes. It was initially led by a single consultant (SC) in 2014, and subsequently evolved to a weekly consultant rotation (WC) roster in 2017 to achieve sustainability. METHODS: Each consultant led the ESAT WC service for a week and maintained ownership of their patients thereafter. All emergency surgical admissions between two distinct 6-month periods were reviewed, from May to October 2014 (pre-ESAT) and January to June 2017 (ESAT WC). Patient demographics, diagnoses, and operations were compared. Efficiency and clinical outcomes were evaluated. RESULTS: There were 1248 and 1284 patients in the pre-ESAT and ESAT WC group, respectively. Majority were males and in their 50s. Acute appendicitis, gallstone conditions, and soft-tissue infections made up half of the admissions. Trauma workload was comparable (7.8% pre-ESAT vs 9.5% ESAT WC). Cholecystectomies doubled during the ESAT period, 14.2% vs 7.2%, (p = 0.01). More consultants were involved in major cases (95.9% vs 86%), (p = 0.01) and more operations were performed during the day (52.1% vs 47.9%), (p = 0.01). Average time to OT was shorter and there were less major surgical complications (p = 0.02). Mortality (p = 0.08) and length of stay were reduced (4 vs 4.5 days), (p = 0.01). CONCLUSION: The ESAT WC service has sustained improved outcomes in our institution.

Anatomically-distinct genetic associations of APOE epsilon4 allele load with regional cortical atrophy in Alzheimer's disease.

APOE epsilon4 is the best-established genetic risk factor for sporadic Alzheimer's disease (AD). However, while homozygotes show greater disease susceptibility and earlier age of onset than heterozygotes, they may not show faster rates of clinical progression. We hypothesize that there are differential APOE epsilon4 allele-load dependent influences on neuropathology across the brain. Our aim was to define the relationship between APOE epsilon4 allele load and regionally-specific brain cortical atrophy in Alzheimer's Disease (AD). For this reason voxel-based morphometry (VBM) was performed using T1-weighted MR images from 83 AD patients, contrasting regional cortical grey matter by APOE epsilon4 load according to either dominant or genotypic models. Patients fulfilled NINCDS-ADRDA criteria and were genotyped for APOE epsilon4 (15 epsilon4/epsilon4, 39 epsilon4/- and 29-/-). We observed that grey matter volume (GMV) decreased additively with increasing allele load in the medial (MTL) and anterior temporal lobes bilaterally. By contrast, a 2 degree-of-freedom genotypic model suggested a dominant effect of the APOE epsilon4 allele in the left temporal lobe. Brain regions showing a significant APOE epsilon4 allele load effect on GMV in AD included only some of those typically described as having greatest amyloid plaque deposition and atrophy. Temporal regions appeared to show a dominant effect of APOE epsilon4 allele load instead of the additive effect previously strongly associated with age of onset. Regional variations with allele load may be related to different mechanisms for effects of APOE epsilon4 load on susceptibility and disease progression.