Abnormal Scans Research Articles

Peri-injury symptomatology as predictors of brain computed tomography (CT) scan abnormalities in mild traumatic brain injury (mTBI)

ObjectiveThis study aimed to identify predictors of brain CT abnormalities in patients who sustained a mild traumatic brain injury (mTBI).MethodsRetrospective observational cohort of adult patients with mTBI (Glasgow Coma Score 13–15) that occurred within the preceding 24 h.Results2548 (91%) of the cohort had a brain CT and 698 (27%) demonstrated abnormal findings. The most frequently observed CT abnormalities were bleeding (638, 25%) and fractures (190, 7.4%). Multivariate logistic regression analysis revealed several significant predictors associated with the presence of brain CT abnormalities including older age [P < 0.0001], male sex [P < 0.0001], loss of consciousness [P = 0.0041], associated vomiting [P = 0.0011], alteration of consciousness (AOC) [P = 0102], and GCS score [P < 0.0001]. This was a robust model with an R² of 14.2%.ConclusionIn this retrospective analysis, older age, male sex, the presence of loss of consciousness or alteration in consciousness, lower GCS score, and associated vomiting were found to be significant predictors of having an abnormal brain CT. These findings highlight the importance of considering these factors when determining the necessity of brain CT scans in patients with mTBI and suggest that existing clinical decision rules may be limited. These findings may also help to inform clinical decision rules. Early identification of individuals at a higher risk of CT abnormalities may assist in appropriate management and allocation of healthcare resources.

Deep Learning Methods for Detecting Chest X-Ray and CT Scan Abnormalities

Deep learning's quick development has created new opportunities to improve medical image analysis, especially in the identification of anomalies in chest CT and X-ray scans. This work investigates several deep learning techniques designed for this particular purpose to enhance the efficiency and accuracy of diagnosis in medical settings. We explore the use of 3D CNNs, transfer learning, and convolutional neural networks, or CNNs, for the analysis of volumetric CT scan information as well as 2D chest X-ray pictures. Comparative analyses show the benefits and drawbacks of various deep learning architectures for identifying a variety of anomalies, including tumors, tumors in the lungs, pneumonia, and other diseases. We also go over the significance of preprocessing methods, assessment metrics specifically designed for medical picture analysis, and dataset preparation. The results highlight how deep learning has the potential to revolutionize chest imaging diagnostics by facilitating the quicker and more accurate identification of anomalies, which will enhance patient outcomes and the effectiveness of healthcare delivery. To spur additional developments in the deep learning-powered analysis of medical images for chest problems, future research topics, and obstacles in this area are also covered.

6537 Recurrent Graves Thyrotoxicosis After Prolonged Radioiodine-Induced Hypothyroidism

Abstract Disclosure: H.K. Deveaux: None. A. Gundeti: None. K. Mitrollari: None. A.P. Calimag: None. T. Yasmeen: None. Radioactive iodine (I-131) ablation (RAI) is one of the effective therapies for Graves’ disease (GD). Successful treatment is indicated by sustained, irreversible hypothyroidism requiring lifelong replacement for which recurrence of disease rarely develops. Recurrent hyperthyroidism is a rare development without apparent predisposition. Here, we describe a case of recurrent thyrotoxicosis after 36 years of RAI.70-year-old female PMH atrial fibrillation (AFib) on apixaban s/p cardioversion, HTN, HFpEF, Pulmonary HTN, and Graves’ Disease s/p RAI ablation 36 years ago with RAI-induced hypothyroidism. The patient was initially on levothyroxine for post-ablative hypothyroidism and stopped taking levothyroxine around 2019. NM scintigraphy done in 2019 showed an abnormal I-123 thyroid uptake and scan with the five-hour radioiodine thyroid uptake showed mildly hyperthyroid. On the thyroid scan, there is a note of a prominent pyramidal lobe with some thyroid gland asymmetry. In 2022, the patient was admitted for new-onset AFib and was noted to have subclinical hyperthyroidism with TSH 0.157, fT4 1.4, TrAb&amp;gt;40, and TSI 34.8. The patient was started on methimazole, which she stopped one month later. During this admission, the patient presented secondary to a mechanical fall and was found to be in AFib with a rapid ventricular rate. Her labs were significant for TSH&amp;lt;0.008 fT4 4.2, TrAb &amp;gt;40. Methimazole was restarted with maximal doses of diltiazem and metoprolol for rate control. Thyroid ultrasound demonstrated an enlarged, heterogeneous thyroid gland with increased vascularity and multiple bilateral TR3 thyroid nodules.Hyperthyroidism affects approximately 1.2% of the population. GD involves autoantibodies activating the thyrotropin receptor, increasing synthesis and release of thyroid hormone and is for 50-60% of cases with a 5-to-10-fold preference for females. RAI ablation is preferred, being inexpensive, with a cure rate approaching 100%. The incidence of transient hypothyroidism post-RAI varies from 9-17%. Retrospective studies have observed hyperthyroidism within the first 12 months post-RAI; however, some cases have seen a resurgence as late as 22 years later. Recurrent hyperthyroidism is an uncommon occurrence with various postulated aetiologies, such as inadequate dosing/incomplete ablation with residual cells remaining viable and regenerating in the setting of increased TSIiv, Marine-Lenhart syndrome (MLS), or an unclear mechanism associated with autoimmunity in the presence of TSI. Hyperthyroidism rarely recurs in GD after successful post-ablative treatment with RAI. Our case, while an uncommon presentation and underlying aetiology yet to be determined, illustrates the importance of continued surveillance, even after successful treatment.‌ Presentation: 6/3/2024

Pulmonary sequestration associated with pulmonary actinomycosis: A case report and literature review.

Pulmonary sequestration (PS), a rare pulmonary disease, arises from congenital pulmonary vascular dysplasia. Meanwhile, pulmonary actinomycosis is a purulent infection of lung lesions triggered by the inhalation of actinomycetes, which is also uncommon. Even rarer is the occurrence of pulmonary actinomycete infection secondary to PS. Herein, we present a case report of such a rare occurrence. The 21-year-old female patient had been erroneously diagnosed with pneumonia and tuberculosis, presenting symptoms of cough, sputum, and hemoptysis; however, the implemented anti-infection and antituberculosis treatments proved to be ineffective. The diagnosis of the sequestration in the right lower lung was confirmed through an enhanced chest CT scan and a 3-dimensional reconstruction of the pulmonary vessels. During the surgical video-assisted thoracoscopic resection of the right lower lobe lesion, it was discovered that the isolated lung tissue's blood supply vessel originated from the thoracic aorta. Additionally, the pathological examination revealed that the lung tissue of the right lower lobe lesion was infected with pulmonary actinomycetes. Following thorough evaluation, the patient received a final diagnosis of pulmonary actinomycete infection that occurred secondary to right lower lung sequestration. Consequently, they underwent treatment consisting of high-dose penicillin administered for a period of 6 months post-operation. Over the course of the subsequent 23-month follow-up, no recurrence of the infection or abnormal CT scan findings were observed. Pulmonary sequestration bears clinical resemblance to pulmonary actinomycetes. In cases where recurrent episodes of pneumonia occur at the same location, and chest imaging indicates persistent lesions in the basal segment of the lower lobe near the spine, the possibility of PS should be considered. Prompt chest-enhanced CT and 3-dimensional reconstruction of pulmonary vessels are crucial for a definitive diagnosis. Imaging findings such as mass-like consolidation, cystic lesions, liquefactive necrosis, and pneumonia-like changes, coupled with typical air suspension signs and sulfur-like particles visible under tracheoscopy, suggest a potential pulmonary actinomycete infection. Timely biopsy is essential to confirm the diagnosis and prevent missed or incorrect diagnoses.

Accuracy of Diagnosing Optic Neuritis Using DANTE T1-SPACE Imaging.

To evaluate the use of delay alternating with nutation for tailored excitation-prepared T1-weighted turbo spin echo (DANTE T1-SPACE) imaging for diagnosing optic neuritis and to analyze its correlation with clinical findings before and after treatment. Patients diagnosed with optic neuritis or non-arteritic anterior ischemic optic neuropathy (NA-AION) were evaluated at the Ophthalmology Department of Kyoto University Hospital. All patients underwent magnetic resonance (MR) studies before treatment initiation and ophthalmic examinations before and after treatment. Three ophthalmologists independently reviewed the MR scans for abnormalities. The magnetic resonance imaging (MRI) assessments included post-contrast DANTE T1-SPACE, post-contrast volumetric interpolated breath-hold examination (VIBE), and short T1 inversion recovery (STIR) scans. The presence of abnormalities in each sequence was determined. Of 36 eyes from 30 patients, 21 eyes from 17 patients were diagnosed with optic neuritis, and 15 eyes from 13 patients were diagnosed with NA-AION. DANTE T1-SPACE sequences showed better sensitivity for detecting optic neuritis than STIR sequences (100% vs 67%, p = 0.009). VIBE images did not confirm enhancement of lesions in some cases with optic neuritis. No differences were observed among the sequences for NA-AION. Lesion length evaluated by DANTE T1-SPACE sequences was associated with circumpapillary retinal nerve fiber layer thickness at the initial visit, eye pain, and the time interval from symptom onset to MRI scan. Contrast-enhanced DANTE T1-SPACE was better than other sequences of MRI for diagnosing optic neuritis.

ThP8.8 - Role of Lymphoscintigraphy in Lymphoedema

Abstract Aim Lymphoscinigraphy (LSG) is a gold standard of investigation in patients with Lymphoedema, though not all patients with Lymphoedema are offered LSG and some who are offered decline to have the test. The aim of the present study was to do a clinico-radiological correlation of Lymphoscintigraphic findings. Methods All patients who underwent Lymphoscinti scans at a tertiary vascular centre over a 3 year period were included in the study. The technique was standardised and involved injection of a radioactive tracer in the Ist web space of both feet and uptake of the tracer at the groin at 2 hours was determined. Uptake less than 8% at 2 hours was considered abnormal. Clinical findings were compared with scan findings. Results 207 patients underwent LSG scans for suspected lower limb lymphoedema. 53 (26%) scans were normal. Of those with abnormal scans, 24 had mild lymphatic dysfunction (uptake 5-8%); 57 (28%) had moderate lymphatic dysfunction (uptake 2-5%) and 73 (35%) had severe lymphatic dysfunction with an uptake of &amp;lt;2%. Male to female ratio was 1:3. Median age at presentation was 60 years (range 3-89). Median BMI was 37Kg/m2 (range 17-71). Clinical profile based on the worst leg having moderate to severe Lymphatic dysfunction on LSG showed a 78-93% match between the leg affected and the LSG findings. This dropped to 29% in those with mild dysfunction. Conclusion Lymphoscintigraphy can objectively confirm and grade lymphoedema. It can be used to guide patients and their carers in following preventative measures to prevent complications.

Renal Cortical Imaging with Tc-99m DMSA in Children: An Institutional Review.

Background Urinary tract infection (UTI) is one of the commonly encountered conditions in children. Dimercaptosuccinic acid (DMSA) scintigraphy is widely advocated for functional and morphological evaluation of the renal cortex including parenchymal defect. Moreover, only a small percentage of renal defects are detected by ultrasound. We aimed to examine DMSA scintigraphy of children and identify factors associated with cortical defect. Methods Patients aged ≤ 18 years old who underwent DMSA scintigraphy (November 18, 2019-February 2, 2023, 30 children) were included. All children received intravenous injections of 99m Tc-DMSA followed by static planar and single-photon-emission computed tomography imaging at 3 hours. Cortical findings and differential functions of the worst affected kidney were graded accordingly. Grade I has no more than two cortical defects, grade II has more than two cortical defects with normal parenchyma between the defects, while grade III is when generalized damage is noted, and grade IV is when a shrunken kidney is seen with no DMSA uptake. Normal functioning kidney is when the relative function at 45 to 55%, mildly reduced function at 40 to 44%, and substantially impaired function at 10 to 39%, while nonfunctioning is when the differential split renal function < 10%. All data were then statistically analyzed. Results Majority was female (53%). The mean age was 5.85 years. UTI episodes were 73%. Twenty-two children had congenital urinary tract anomalies. All patients with vesicoureteric refluxes (VURs) had positive defects. Scintigraphy showed abnormalities in 17 children affecting unilateral (64%) or both kidneys (36%). There were 17 children (57%) respectively in the abnormal DMSA scan findings category with normal until significant impairment of the functioning kidney category. VURs were significantly associated with abnormal scintigraphy ( p < 0.05). A significant association was found between abnormal DMSA scan findings and differential renal function ( p < 0.05). Conclusion Significant association was noted between VURs and abnormal DMSA scintigraphy, abnormal DMSA scan findings, and impaired differential renal function. Special consideration should be given to these cases.

Events of children responsible for the development of epilepsy in patients with cerebral palsy

Background: Cerebral palsy (CP) is characterized by abnormal muscle tone, ‘posture, and movement’, thereby limiting the activity of the affected person. Epilepsy is said to occur in 15-90% of children with CP. The aim of this study was to evaluate the events of children responsible for the development of epilepsy considering natal, postnatal characteristics and associated impairment in patients with CP. Methods: This was a case-control study and was conducted in the Department of Pediatric Neurology at the National Institute of Neurosciences and Hospital, Dhaka, Bangladesh during the period from January 2020 to December 2020. In total 150 children with cerebral palsy were enrolled in this study who were divided into two groups. In the ‘CP with epilepsy’ group, there were 50 patients, and in the CP without epilepsy group taken as a case group, there were 100 age-sex matched CP patients without epilepsy patients were taken as a control group. Informed written consent was taken from all the parents. Along with baseline characteristics, data regarding natal, postnatal events, general clinical findings, psychological assessment, computed tomography (CT) scan findings of the head, and electroencephalogram (EEG) findings in epilepsy cases were recorded in a predesigned questionnaire and analyzed. Results: In distributing the CP patients’ comparison regarding postnatal complications neonatal seizures were a strong predictor for epilepsy (p≤0.001). 1st seizure during 1st year of life and family history of epilepsy was also a significant event of epilepsy (p≤0.001). In the case of microcephaly, no significant difference was observed between groups (p=0.278). A significant difference was observed when the distribution of severity of intellectual disability of CP patients was compared between groups (p&lt;0.001). Abnormal CT scan findings of the head were significantly higher in CP with epilepsy 42 (84.0%) than in CP without epilepsy 46 (46.0%) (p≤0.001). The total mean age at the onset of epilepsy was 13.58±14.47 months. Epilepsy was most common in spastic quadriplegic CP (54%). 38.0% had focal epileptiform activity on EEG. Clinically focal epilepsy was found in 36.0% of cases. Conclusions: This study demonstrates the presence of a history of neonatal seizure, 1st seizure during 1st year of life, a family history of epilepsy, CT scan abnormalities, severe intellectual disability, and spastic quadriplegic CP were the events responsible for the development of epilepsy in children with CP.

Correlation Between the Revised Physiological Trauma Score and CT Scan Results.

Background Trauma-scoring systems are used to triage patients and assist in clinical decision-making. Physiological trauma scores are used for quantitative evaluation of injury severity. However, only a few, such as the Revised Physiological Trauma Score (rPTS), have been proven effective in pre-clinical use. There is a constant need for clinical decision tools that aim to reduce the unnecessary use of CT scans among trauma patients. To our knowledge, no study has directly correlated the rPTS and CT findings. This study aimed to investigate whether the rPTS is correlated with CT scan results and can be used to decrease the use of CT. Methodology This retrospective chart review examined all patients who underwent a pan-CT for trauma in theEmergency Department of King Abdulaziz Medical City, Jeddah, from 2008 to 2012. Results We analyzed 235 patients. There was a significant difference in the mean rPTS between those with negative versus positive pan-CT scans (11.4 ± 1.3 vs. 10.9 ± 1.7, respectively; p = 0.032). Furthermore, the rate of positive CT scans was significantly higher in those with an rPTS <11 than those with an rPTS of 11 or 12 (87% vs. 74.1%, respectively; p = 0.044). However, 72.7% of patients with an rPTS of 12/12 had a positive pan-CT scan. Conclusions Despite the difference in the frequency of abnormal CT scans, too many patients with normal rPTS had abnormal CT findings. Therefore, the rPTS cannot be used to safely reduce the use of CT scans.

Utility of Torso Imaging for Elderly Patients Sustaining Ground-Level Falls

IntroductionComputed tomography (CT) of the torso has become increasingly common for assessment of fall patients in the emergency department. Some data suggest that older adults (≥65) may benefit from torso imaging more than younger patients. We sought to evaluate the usage and utility of CT imaging for elderly patients presenting after ground-level falls (GLFs) from 1 meter or less at our level 1 trauma center. MethodsPatients ≥18 presenting with GLF in 2015-2019 were included. Data were obtained through chart and trauma registry review. Descriptive statistics were used to summarize the use of CT imaging for patients younger than versus older than 65 y old. Three multivariate logistic regression models with age as a continuous, binary (<65 versus ≥65), or categorical (in multiples of 5) variable were used to investigate whether age is associated with an increased identification of traumatic injury not previously suspected or known based on physical exam (PE) or plain radiograph after GLF. ResultsA total of 522 patients <65 and 673 patients ≥65 y old were included. Older patients were significantly more likely to receive screening chest radiograph, screening pelvic radiograph, brain CT, and neck CT (all P < 0.001), but not torso (chest, abdomen, and pelvis) CT (P = 0.144). On multivariate logistic regression, age was not significantly associated with an increased odds of identification of traumatic injury after torso CT (continuous: adjusted odds ratio [aOR] = 1.01, 95% confidence interval [CI] = 0.99-1.03, P = 0.379; binary: aOR = 0.86, 95% CI = 0.46-1.58, P = 0.619; categorical: aOR = 1.03, 95% CI = 0.94-1.14, P = 0.453). A positive PE was the only variable associated with significantly increased odds of having an abnormal torso CT scan in all models. Only two patients ≥65 y old had injuries identified on torso CT in the context of a negative PE and negative screening imaging. ConclusionsThe rate of torso injury identification in patients sustaining GLF is not associated with age, but is strongly associated with positive PE findings. In the subset of elderly GLF patients without positive torso PE findings, more conservative use of CT imaging could decrease health-care utilization costs without compromising patient care.

Study protocol for a prospective, multicentre study of hypercortisolism in patients with difficult-to-control type 2 diabetes (CATALYST): prevalence and treatment with mifepristone

IntroductionEven with recent treatment advances, type 2 diabetes (T2D) remains poorly controlled for many patients, despite the best efforts to adhere to therapies and lifestyle modifications. Although estimates vary, studies...

Effect of Beta-Blocker Consumption on the Severity and Extension of Perfusion Defects in Dipyridamole Myocardial Perfusion Single-Photon Emission Computed Tomography.

Background Regarding the less-known effects of beta-blocker consumption on the diagnostic value of the myocardial perfusion scan with dipyridamole stress in coronary artery disease (CAD), we aimed to compare the findings of the scans done on the beta-blocker consumption course and after discontinuation of this medications. Materials and Methods Thirty patients with probably CAD and abnormal myocardial perfusion scans (presence of reversible defect), who had been treated with beta-blockers for at least 3 months, were studied. Dipyridamole stress phase of myocardial perfusion single-photon emission computed tomography (SPECT) was performed two times with an interval of about 1 week, once after discontinuation of all antianginal and anti-ischemic medications, statins, and beta-blockers for 72 hours prior to the study, and again after discontinuation of all these medications except for beta-blockers. Imaging was done with the same protocol, radiopharmaceutical dose, and imaging parameters. Summed stress score (SSS), summed stress rest, and summed difference scores (SDS), total perfusion deficit (TPD), severity, and extension of myocardial perfusion defects in three coronary artery territories were analyzed, using quantitative perfusion SPECT software. Results Most variables such as SSS, SDS, TPD, severity, and extension of defects showed a significant difference between the two conditions including beta-blocker consumption and after discontinuing beta-blocker consumption before stress imaging ( p < 0.05). Moreover, in patients on treatment with metoprolol, all studied factors including SSS, SDS, TPD, severity, and extension of perfusion defects were significantly reduced when patients consumed beta-blockers before SPECT evaluation ( p < 0.05). Conclusion Beta-blocker consumption can lead to a decrease in the severity and extent of myocardial perfusion defects and therefore probably a decrease in the sensitivity of myocardial scans. Discontinuation of beta-blocker prior to the dipyridamole myocardial perfusion scan can improve diagnostic accuracy.

Neuropathologic Validation and Diagnostic Accuracy of Presynaptic Dopaminergic Imaging in the Diagnosis of Parkinsonism.

Degeneration of the presynaptic nigrostriatal dopaminergic system is one of the main biological features of Parkinson disease (PD), multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and corticobasal degeneration (CBD), which can be measured using single-photon emission CT imaging for diagnostic purposes. Despite its widespread use in clinical practice and research, the diagnostic properties of presynaptic nigrostriatal dopaminergic (DAT) imaging in parkinsonism have never been evaluated against the diagnostic gold standard of neuropathology. The aim of this study was to evaluate the diagnostic parameters of DAT imaging compared with pathologic diagnosis in patients with parkinsonism. Retrospective cohort study of patients with DAT imaging for the investigation of a clinically uncertain parkinsonism with brain donation between 2010 and 2021 to the Queen Square Brain Bank (London). Patients with DAT imaging for investigation of pure ataxia or dementia syndromes without parkinsonism were excluded. Those with a pathologic diagnosis of PD, MSA, PSP, or CBD were considered presynaptic dopaminergic parkinsonism, and other pathologies were considered postsynaptic for the analysis. DAT imaging was performed in routine clinical practice and visually classified by hospital nuclear medicine specialists as normal or abnormal. The results were correlated with neuropathologic diagnosis to calculate diagnostic accuracy parameters for the diagnosis of presynaptic dopaminergic parkinsonism. All of 47 patients with PD, 41 of 42 with MSA, 68 of 73 with PSP, and 6 of 10 with CBD (sensitivity 100%, 97.6%, 93.2%, and 60%, respectively) had abnormal presynaptic dopaminergic imaging. Eight of 17 patients with presumed postsynaptic parkinsonism had abnormal scans (specificity 52.9%). DAT imaging has very high sensitivity and negative predictive value for the diagnosis of presynaptic dopaminergic parkinsonism, particularly for PD. However, patients with CBD, and to a lesser extent PSP (of various phenotypes) and MSA (with predominant ataxia), can show normal DAT imaging. A range of other neurodegenerative disorders may have abnormal DAT scans with low specificity in the differential diagnosis of parkinsonism. DAT imaging is a useful diagnostic tool in the differential diagnosis of parkinsonism, although clinicians should be aware of its diagnostic properties and limitations. This study provides Class II evidence that DAT imaging does not accurately distinguish between presynaptic dopaminergic parkinsonism and non-presynaptic dopaminergic parkinsonism.

Revolutionizing Neurology: The Role of Artificial Intelligence in Advancing Diagnosis and Treatment.

Artificial intelligence (AI) has emerged as a powerful tool in the field of neurology, significantly impacting the diagnosis and treatment of neurological disorders. Recent technological breakthroughs have given us access to a plethora of information relevant to many aspects of neurology. NeuroscienceandAIshare a long history of collaboration.Along with great potential, we encounter obstacles relating to data quality, ethics, and inherent difficulty in applying data science in healthcare. Neurological disorders pose intricate challenges due to their complex manifestations and variability.Automating image interpretation tasks, AI algorithms accurately identify brain structures and detect abnormalities. This accelerates diagnosis and reduces the workload on medical professionals. Treatment optimization benefits from AI simulations that model different scenarios and predict outcomes. These AI systems can currently perform many of the sophisticated perceptual and cognitive capacities of biological systems, such as object identification and decision making. Furthermore, AI is rapidly being used as a tool in neuroscience research, altering our understanding of brain functioning. It has the ability to revolutionize healthcare as we know it into a system in which humans and robots collaborate to deliver better care for our patients.Image analysis activities such as recognizing particular brain regions, calculating changes in brain volume over time, and detecting abnormalities in brain scans can be automated by AI systems. This lessens the strain on radiologists and neurologists while improving diagnostic accuracy and efficiency.It is now obvious that cutting-edge artificial intelligence models combined with high-quality clinical data will lead to enhanced prognostic and diagnostic models in neurological illness, permitting expert-level clinical decision aids across healthcare settings.In conclusion, AI's integration into neurology has revolutionized diagnosis, treatment, and research. As AI technologies advance, they promise to unravel the complexities of neurological disorders further, leading to improved patient care and quality of life. The symbiosis of AI and neurology offers a glimpse into a future where innovation and compassion converge to reshape neurological healthcare. This abstract provides a concise overview of the role of AI in neurology and its transformative potential.

Abnormal Scanning Patterns Based on Eye Movement Entropy in Early Psychosis

BackgroundRestricted scan path mode is hypothesized to explain abnormal scanning patterns in patients with schizophrenia. Here, we calculated entropy scores (drawing on gaze data to measure the statistical randomness of eye movements) to quantify how strategical and random participants were when processing image stimuli. MethodsEighty-six patients with first-episode schizophrenia (FES), 124 individuals at clinical high risk (CHR) for psychosis, and 115 healthy control participants (HCs) completed an eye-tracking examination while freely viewing 35 static images (each presented for 10 seconds) and cognitive assessments. We compared group differences in the overall entropy score, as well as entropy scores under various conditions. We also investigated the correlations between entropy scores and symptoms and cognitive function. ResultsIncreased overall entropy scores were noted in the FES and CHR groups compared with the HC group, and these differences were already apparent within 0 to 2.5 seconds. In addition, the CHR group exhibited higher entropy than the HC group when viewing low-meaning images. Moreover, the entropy within 0 to 2.5 seconds showed significant correlations with negative symptoms in the FES group, attention/vigilance scores in the CHR group, and speed of processing and attention/vigilance scores across all 3 groups. ConclusionsThe results indicate that individuals with FES and those at CHR scanned pictures more randomly and less strategically than HCs. These patterns also correlated with clinical symptoms and neurocognition. The current study highlights the potential of the eye movement entropy measure as a neurophysiological marker for early psychosis.

Combining plasma Aβ and p-tau217 improves detection of brain amyloid in non-demented elderly

BackgroundMaximizing the efficiency to screen amyloid-positive individuals in asymptomatic and non-demented aged population using blood-based biomarkers is essential for future success of clinical trials in the early stage of Alzheimer’s disease (AD). In this study, we elucidate the utility of combination of plasma amyloid-β (Aβ)-related biomarkers and tau phosphorylated at threonine 217 (p-tau217) to predict abnormal Aβ-positron emission tomography (PET) in the preclinical and prodromal AD.MethodsWe designed the cross-sectional study including two ethnically distinct cohorts, the Japanese trial-ready cohort for preclinica and prodromal AD (J-TRC) and the Swedish BioFINDER study. J-TRC included 474 non-demented individuals (CDR 0: 331, CDR 0.5: 143). Participants underwent plasma Aβ and p-tau217 assessments, and Aβ-PET imaging. Findings in J-TRC were replicated in the BioFINDER cohort including 177 participants (cognitively unimpaired: 114, mild cognitive impairment: 63). In both cohorts, plasma Aβ(1-42) (Aβ42) and Aβ(1-40) (Aβ40) were measured using immunoprecipitation-MALDI TOF mass spectrometry (Shimadzu), and p-tau217 was measured with an immunoassay on the Meso Scale Discovery platform (Eli Lilly).ResultsAβ-PET was abnormal in 81 participants from J-TRC and 71 participants from BioFINDER. Plasma Aβ42/Aβ40 ratio and p-tau217 individually showed moderate to high accuracies when detecting abnormal Aβ-PET scans, which were improved by combining plasma biomarkers and by including age, sex and APOE genotype in the models. In J-TRC, the highest AUCs were observed for the models combining p-tau217/Aβ42 ratio, APOE, age, sex in the whole cohort (AUC = 0.936), combining p-tau217, Aβ42/Aβ40 ratio, APOE, age, sex in the CDR 0 group (AUC = 0.948), and combining p-tau217/Aβ42 ratio, APOE, age, sex in the CDR 0.5 group (AUC = 0.955), respectively. Each subgroup results were replicated in BioFINDER, where the highest AUCs were seen for models combining p-tau217, Aβ42/40 ratio, APOE, age, sex in cognitively unimpaired (AUC = 0.938), and p-tau217/Aβ42 ratio, APOE, age, sex in mild cognitive impairment (AUC = 0.914).ConclusionsCombination of plasma Aβ-related biomarkers and p-tau217 exhibits high performance when predicting Aβ-PET positivity. Adding basic clinical information (i.e., age, sex, APOE ε genotype) improved the prediction in preclinical AD, but not in prodromal AD. Combination of Aβ-related biomarkers and p-tau217 could be highly useful for pre-screening of participants in clinical trials of preclinical and prodromal AD.

Percutaneous Balloon-Expandable Stent Implantation to Treat Transverse Aortic Arch Obstruction: Medium- to Long-Term Outcomes of a Retrospective Multicenter Study.

Transverse aortic arch obstruction is a challenging lesion for which stent implantation provides a potentially important alternate therapy. The objectives were to evaluate the technical, procedural, and medium-to-long-term clinical outcomes of percutaneous stent implantation of transverse aortic arch obstruction. This is a retrospective, multicenter study of transverse aortic arch stent implantation. Univariable and multivariable analyses were performed. Index catheterization included 187 stent implants in 146 patients. The median age is 14.3 years (interquartile range, 9.3-19), weight is 53 kg (30-69), and follow-up is 53 months (12-120). The most common stent design was open cell (n=90, 48%). Stents overlapped 142 arch vessels (37 carotid arteries) in 118 (81%) cases. Technical and procedural success rates were 100% and 88%, respectively. Lower weight (P=0.018), body surface area (P=0.013), and minimum-to-descending aortic diameter ratio (P<0.001) were associated with higher baseline aortic gradient. The residual gradient was inversely associated with implant and final dilation diameters (P<0.001). The combined incidence of aortic injury and stent-related complications was 14%. There were no reports of abnormal brain scans or stroke. Blood pressure cuff gradient, echocardiographic arch velocity, and hypertension rates improved within 1-year follow-up with increased antihypertensive medication use. Reintervention was reported in 60 (41%) patients at a median of 84 (22-148) months to first reintervention. On multivariable logistic regression, residual aortic gradient >10 mm Hg was associated with increased odds of reintervention at all time points when controlling for each final dilation diameter, weight, and minimum-to-descending aortic diameter ratio. Transverse aortic arch stent implantation has high rates of technical, procedural, and medium-to-long-term clinical success. Aortic gradient >10 mm Hg is associated with increased odds of reintervention at 1-year and most recent follow-ups. Open cell stent design was frequently used for its advantages in conformability, perfusion of arch vessels, low fracture rate, and the ability to perform effective angioplasty of side cells.

Multi-center study on mortality in children, and adults with sickle cell anemia-risk factors and causes of death

Sickle cell disease (SCD) is a major public health burden worldwide with increasing morbidity and mortality. The study evaluates the risk factors associated with mortality in SCD patients, between the years 2006 and 2020 at three hospitals in Oman. The analysis includes clinical manifestations, haematological, biochemical, and radiological parameters, use of antibiotics, and blood and exchange transfusions. Our cohort included 123 patients (82 males, 41 females), with a median age of 27 (Interquartile Range 21–35 years). SCD related complications included acute chest syndrome (ACS) in 52.8%, splenic sequestration in 21.1%, right upper quadrant syndrome in 19.5%, more than > 6 VOC/year in 17.9%, and stroke in 13.8%. At the terminal admission, patients had cough, reduced O2 saturation, crepitation and fever in 24.4%, 49.6%, 53.6% and 68.3% respectively. Abnormal chest X-ray and chest CT scan were seen in 57.7%, and 76.4% respectively. Laboratory parameters showed a significant drop in hemoglobin (Hb) and platelet counts from baseline, with a significant rise in WBC, LDH and CRP from baseline (p < 0.05, Wilcoxon Signed Ranks test). All patients received antibiotics, whereas, 95.9% and 93.5% received simple blood transfusions, and exchange transfusions respectively, and 66.6% required non-invasive ventilation. Among the causes of death, ACS is seen in 32 (26%), sepsis in 49 (40%), and miscellaneous in 42 (34%). Sudden death was seen in 32 (26%) of patients. Male gender, with low HbF, rapid drop in Hb and platelet, and increased in WBC, LDH, ferritin, and CRP, correlated significantly with mortality in this cohort.

Risk-based lung cancer screening performance in a universal healthcare setting.

Globally, lung cancer is the leading cause of cancer death. Previous trials demonstrated that low-dose computed tomography lung cancer screening of high-risk individuals can reduce lung cancer mortality by 20% or more. Lung cancer screening has been approved by major guidelines in the United States, and over 4,000 sites offer screening. Adoption of lung screening outside the United States has, until recently, been slow. Between June 2017 and May 2019, the Ontario Lung Cancer Screening Pilot successfully recruited 7,768 individuals at high risk identified by using the PLCOm2012noRace lung cancer risk prediction model. In total, 4,451 participants were successfully screened, retained and provided with high-quality follow-up, including appropriate treatment. In the Ontario Lung Cancer Screening Pilot, the lung cancer detection rate and the proportion of early-stage cancers were 2.4% and 79.2%, respectively; serious harms were infrequent; and sensitivity to detect lung cancers was 95.3% or more. With abnormal scans defined as ones leading to diagnostic investigation, specificity was 95.5% (positive predictive value, 35.1%), and adherence to annual recall and early surveillance scans and clinical investigations were high (>85%). The Ontario Lung Cancer Screening Pilot provides insights into how a risk-based organized lung screening program can be implemented in a large, diverse, populous geographic area within a universal healthcare system.

Abstract 1071: Circulation of rare events in the liquid biopsy for early detection of lung mass lesions

Abstract Lung cancer screening with low-dose CT scans (LDCT) has reduced mortality for patients with high-risk smoking histories. However, this method of screening remains imperfect. High rates of false positive scans expose patients to additional morbidity as they pursue subsequent diagnostic evaluation. Real-world application of screening LDCT remains low. Finally, current screening guidelines exclude those without smoking histories, a population which comprises up to a quarter of lung cancer patients. We sought to explore the utility of liquid biopsy (LBx) in lung cancer patients and its use in early cancer screening and diagnosis. Using the third generation High-Definition Single Cell Assay (HDSCA3.0) workflow, we analyzed 99 peripheral blood samples divided into three cohorts: Normal Donors (ND, n=50) who were healthy volunteers with no known pathology, Screening CT patients (CT, n=25) who underwent standard LDCT screening with resultant Lung-RADS 1-2, Biopsy patients (BX, n=24) who had abnormal CT scans requiring tissue biopsy. The ND group was used to characterize baseline epithelial, mesenchymal, endothelial, and immune cells, alongside acellular events (oncosomes). For the CT and BX patients, demographic information including age, gender, and average BMI was roughly equivalent, however average pack-years smoked differed owing to 10 (42%) patients in the BX group who had no prior smoking history. A total of 14 (58%) BX patients were diagnosed with primary lung cancer (BX+), of which 11(75%) were adenocarcinoma, 2 (19%) were squamous cell carcinoma and 1 (6%) was small cell. Across the cohorts we observed intra- and interpatient heterogeneity of rare events including multiple phenotypic rare cell populations and oncosomes. The comparison of the rare event enumerations between the ND, CT, BX+, and BX- cohorts revealed a greater incidence of total events, total rare cells and oncosomes, as well as specific cellular phenotypes in the CT and BX cohorts compared to the ND cohort. LBx analytes were detected at a significant elevation in the BX samples compared to the CT samples, but there was no significant difference between BX+ and BX- samples. The data supports the utility of the LBx in distinguishing patients with an alveolar mass lesion from those without, providing a mechanism for screening prior to LDCT to better inform clinical workup and avoid unnecessary radiation exposure and biopsy. Citation Format: Anya Shah, Karen Resnick, Jeremy Mason, Peter Kuhn, Jorge Nieva, Stephanie Shishido. Circulation of rare events in the liquid biopsy for early detection of lung mass lesions [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1071.