Computed Tomography Evidence Research Articles

Incidental osteoarthritis: risk factors, prevalence and clinical evidence in rabbits

Aim: The objective of this retrospective cohort study was to evaluate the prevalence, risk factors and level of clinically apparent disease associated with appendicular osteoarthritis in a population of rabbits under veterinary care. Method: Computed tomography reports of 311 rabbits taken for any reason over a 4-year period were evaluated for recorded evidence of appendicular osteoarthritis and the joint(s) affected. Risk factors including age, weight, body condition, breed, sex and neuter status were investigated. In rabbits with evidence of osteoarthritis, clinical notes were examined to evaluate if the condition was clinically apparent. Findings: Out of 311 computed tomography reports, 61 described evidence of osteoarthritis (19.6%). The most common joints affected were the elbow and stifle. No significant relationship between sex, body condition and neuter status in males and presence of osteoarthritis was found. A statistically significant relationship between greater age, greater weight and neuter status in females and the presence of osteoarthritis was found. Only 9 out of 61 (14.8%) of the rabbits with computed tomography evidence of osteoarthritis had clinical signs of osteoarthritis recorded in the clinical notes. Conclusions: Following the results of this study, it may be concluded that greater age and weight, as well as female neuter status, are related to increased risk of appendicular osteoarthritis in rabbits, but changes on imaging may relate poorly to clinically apparent disease.

Cluster Analysis of World Trade Center Related Lower Airway Diseases.

Introduction: Cluster analysis can classify without a priori assumptions the heterogeneous chronic lower airway diseases found in former workers at the World Trade Center (WTC) disaster site. Methods: We selected the first available chest computed tomography scan with quantitative computed tomography measurements on 311 former WTC workers with complete clinical, and spirometric data from their closest surveillance visit. We performed a nonhierarchical iterative algorithm K-prototype cluster analysis, using gap measure. Results: A five-cluster solution was most satisfactory. Cluster 5 had the healthiest individuals. In cluster 4, smoking was most prevalent and intense but there was scant evidence of respiratory disease. Cluster 3 had symptomatic subjects with reduced forced vital capacity impairment (low FVC). Clusters 1 and 2 had less dyspneic subjects, but more functional and quantitative computed tomography evidence of chronic obstructive pulmonary disease (COPD) in cluster 1, or low FVC in cluster 2. Clusters 1 and 4 had the highest proportion of rapid first-second forced expiratory volume decliners. Conclusions: Cluster analysis confirms low FVC and COPD/pre-COPD as distinctive chronic lower airway disease phenotypes on long-term surveillance of the WTC workers.

Chronic respiratory disorders due to aberrant innominate artery: a case series and critical review of the literature

BackgroundTracheal compression (TC) due to vascular anomalies is an uncommon, but potentially serious cause of chronic respiratory disease in childhood. Vascular slings are congenital malformations resulting from abnormal development of the great vessels; in this group of disorders the most prevalent entity is the aberrant innominate artery (AIA). Here we provide a report on diagnosis and treatment of AIA in nine children with unexplained chronic respiratory symptoms. We describe the cases, perform a literature review, and provide a discussion on the diagnostic workup and treatment that can help manage AIA.MethodsClinical history, diagnostic procedures and treatment before and after the AIA diagnosis were retrospectively reviewed in nine children (5 boys and 4 girls), who were referred for recurrent-to-chronic respiratory manifestations over 10 years (2012–2022). We performed a comprehensive report on the ongoing clinical course and treatment as well as an electronic literature search on the topic.ResultsDiagnoses at referral, before AIA was identified, were chronic dry barking cough associated with recurrent pneumonia (n = 8, 89%), lobar/segmental atelectasis (n = 3, 33%), atopic/non atopic asthma (n = 3, 33%); pneumomediastinum with subcutaneous emphysema complicated the clinical course in one case. When referred to our Unit, all patients had been previously treated with repeated antibiotic courses (n = 9, 100%), alone (n = 6, 67%) or combined with prolonged antiasthma medications (n = 3, 33%) and/or daily chest physiotherapy (n = 2, 22%), but reported only partial clinical benefit. Median ages at symptom onset and at AIA diagnosis were 1.5 [0.08–13] and 6 [4–14] years, respectively, with a relevant delay in the definitive diagnosis (4.5 years). Tracheal stenosis at computed tomography (CT) was ≥ 51% in 4/9 cases and ≤ 50% in the remaining 5 subjects. Airway endoscopy was performed in 4 cases with CT evidence of tracheal stenosis ≥ 51% and confirmed CT findings. In these 4 cases, the decision of surgery was made based on endoscopy and CT findings combined with persistence of clinical symptoms despite medical treatment. The remaining 5 children were managed conservatively.ConclusionsTC caused by AIA may be responsible for unexplained chronic respiratory disease in childhood. Early diagnosis of AIA can decrease the use of expensive investigations or unsuccessful treatments, reduce disease morbidity, and accelerate the path toward a proper treatment.

Extra-cranial hemorrhagic complications in patients with COVID-19 infection: the experience of a secondary care COVID-19 institution

BACKGROUND: COVID-19 patients are considered to be at high risk for thromboembolic events, and are subjected to large doses of anticoagulants. However, the associated risk of major bleeding remains underestimated. The aim of this study was to investigate extracranial major bleeding complications in a cohort of critically ill patients with COVID-19 pneumonia, diagnosed with computed tomography (CT) or magnetic resonance (MR), and to examine their relationship with laboratory data and pro-thrombothic status.METHODS: In this retrospective observational study, patients admitted to a single secondary care center from November 1, 2020 and January 31, 2022, who tested positive for COVID-19 and developed significant anemia (reduction in Hb levels >2 g/dL) over the course of hospitalization were included. Clinical-laboratory parameters and imaging were reviewed.RESULTS: Out of 279 patients, hemorrhagic complications were detected in 18 patients (10 males, 8 females, mean age 78.6 years, range 63-89 years), with CT evidence of atraumatic bleedings in the thoraco-abdominal wall (N.=8, bilaterally in one case), in the thoracic cavity (N.=2), in the iliopsoas compartment (N.=5), and in the intestinal lumen (N.=1). Intra-articular (N.=1) and intraspinal (N.=1) hematomas were also found. 14/18 patients underwent angiographic embolization. Three patients simultaneously showed pulmonary embolism.CONCLUSIONS: Spontaneous major extracranial bleeding, at the thoraco-abdominal level and in other atypical sites, represents a rare but serious complication of COVID-19 infection and must always be considered in case of anemia during the course of the disease and relative hospitalization.

Canal narrowing in adult patients with cervical spinal cord injury without computed tomography evidence of trauma

PurposeCervical spinal cord injury can be a particularly devastating sequela of trauma. The purpose of this study was to describe the imaging findings of adult patients with cervical spinal cord injury without computed tomography evidence of trauma (SCIWOCTET). MethodsAll adult patients (≥18 years) treated for acute cervical SCIWOCTET at a single Level I adult trauma center over an eight-year period were retrospectively identified. CT imaging was evaluated for degenerative changes narrowing the midsagittal canal diameter (SCD) of the cervical spine and relative congenital cervical stenosis (CCS; congenital narrowing of the SCD <13 mm). Magnetic resonance imaging (MRI) scans were evaluated for signal intensity change (SIC) suspicious for cord edema/contusion as well as ligamentous injury, hemorrhage, and epidural hematoma. ResultsNinety-six patients with cervical SCIWOCTET met inclusion criteria. The most common mechanism of injury was fall from standing (47.9%). On CT, 86 patients (89.6%) had CCS. Degenerative changes were present in 95 patients (99.0%). In 98/99 patients (99.0%), the point of narrowest cervical SCD was ≤8 mm. On MRI, 79 patients (82.3%) demonstrated signal intensity change (SIC) indicative of cord edema/contusion, while 16 (16.7%) had ligamentous injury. Intramedullary cord hemorrhage was seen in two patients (2.1%) and epidural hematoma in three (3.1%). ConclusionDegenerative changes or CCS may narrow the minimum cervical SCD beyond the threshold at which low-energy trauma results in C-SCI. Adult patients with cervical spinal stenosis, whether congenital and/or degenerative, and neurologic findings referable to the cervical spine should be assessed for C-SCI.

Prospective Validation of Computed Tomography to Identify Patients at High Risk for Stroke After Transient Ischemic Attack or Minor Stroke.

Computed tomography (CT) findings of acute and chronic ischemia are associated with subsequent stroke risk in patients with transient ischemic attack. We sought to validate these associations in a large prospective cohort of patients with transient ischemic attack or minor stroke. This prospective cohort study enrolled emergency department patients from 13 hospitals with transient ischemic attack who had CT imaging. Primary outcome was stroke within 90 days. Secondary outcomes were stroke within 2 or 7 days. CT findings were abstracted from radiology reports and classified for the presence of acute ischemia, chronic ischemia, or microangiopathy. Multivariable logistic regression was used to test associations with primary and secondary end points. From 8670 prospectively enrolled patients between May 2010 and May 2017, 8382 had a CT within 24 hours. From this total population, 4547 (54%) patients had evidence of acute ischemia, chronic ischemia, or microangiopathy on CT, of whom 175 had a subsequent stroke within 90 days (3.8% subsequent stroke rate; adjusted odds ratio [aOR], 2.33 [95% CI, 1.62-3.36]). This was in comparison to those with CT imaging without ischemia. Findings associated with an increased risk of stroke at 90 days were isolated acute ischemia (6.0%; aOR, 2.42 [95% CI, 1.03-5.66]), acute ischemia with microangiopathy (10.7%; aOR, 3.34 [95% CI, 1.57-7.14]), chronic ischemia with microangiopathy (5.2%; aOR, 1.83 [95% CI, 1.34-2.50]), and acute ischemia with chronic ischemia and microangiopathy (10.9%; aOR, 3.49 [95% CI, 1.54-7.91]). Acute ischemia with chronic ischemia and microangiopathy were most strongly associated with subsequent stroke within 2 days (aOR, 4.36 [95% CI, 1.31-14.54]) and 7 days (aOR, 4.50 [95% CI, 1.73-11.69]). In patients with transient ischemic attack or minor stroke, CT evidence of acute ischemia with chronic ischemia or microangiopathy significantly increases the risk of subsequent stroke within 90 days of index visit. The combination of all 3 findings results in the greatest early risk.

Early Enteral Feeding in Severe Acute Pancreatitis: A Randomized Clinical Trial Between Gastric vs Distal Jejunal Feeding

Background and AimsSevere acute pancreatitis is one of the most catabolic illnesses. Meta-analyses have shown that enteral nutrition is safer and more effective than parenteral nutrition in suppressing these losses. However, there is intense debate about how the enteral nutrition should be delivered. MethodsThe design was a randomized controlled trial of early nasogastric (NG) vs distal jejunal (DJ) tube feeding with a semi-elemental diet during the first 4 weeks of severe acute pancreatitis. The setting involved multiple national tertiary care centers. Two hundred and twenty-eight patients were screened, and 26 met the inclusion criteria for new onset severe acute pancreatitis based on an APACHE II score >8, computed tomography evidence of >30% necrosis or computed tomography score >8, and/or a Marshall score >2. The intervention was a randomized allocation to either feeding tube bedside placement by NG or transnasal endoscopy for DJ. The primary endpoint was “feeding failure” to tolerate a rate of >10% of the goal for a 48-hour period. ResultsTwenty-six eligible patients were randomized, 12 to NG and 14 to DJ, 20 of 26 from the Pittsburgh center. Most were obese (BMI 31.5 kg/m2). Feeding failure occurred in 0 of 14 in the DJ group and in 6 of 11 (55%) in the NG group (P = 0.0026). NG failures were crossed over to DJ feeding with good tolerance and eventual recovery. As a result, the quantity of feed delivered was significantly higher in the DJ group (P < 0.05). Serious adverse events (cardiorespiratory arrests, unrelated to endoscopy) occurred in 2 of the DJ and none of the NG group; 3 patients from the DJ group died of progressive organ failure, 2 with associated compartment syndrome. ConclusionThis randomized controlled trial indicates that in patients with acute pancreatitis of this level of severity, NG feeding will be ineffective. Although this is a common indication for parenteral nutrition, a safer alternative would be endoscopic-assisted DJ feeding tube placement to bypass the usually dysfunctional or obstructed upper gastrointestinal tract.

PET-CT image Co-segmentation of lung tumor using joint level set model

Accurate lung tumor segmentation plays an important role in radiotherapy and targeted therapy. Positron emission tomography (PET) and computed tomography (CT) scanner imaging provide complementary evidence for lung tumor segmentation. In specific, PET can recognize the tumor tissues, while the tissue boundaries are blurred in such a modality. By contrast, CT has a better resolution but a lower contrast between tumor and normal tissues. It is well known that jointly exploiting the evidence from PET and CT images significantly benefits lung tumor delineation. A novel joint level set model is proposed in this paper to integrate PET and CT evidence in a unified energy form, providing co-segmentation results. The convergence result of our co-segmentation model can find the optimal tradeoff between PET and CT modalities. Different characteristics of these two modalities are comprehensively considered in the adaptive convergence process which starts mostly with the PET evidence to locate tumor tissues and stops mostly with the CT evidence to delineate tissue boundaries. The novelty of our joint level set model lies in its adaptability which stepwise moderates joint weights during the model convergence process. The performance of our proposed model is validated on 20 PET-CT images of the nonsmall cell lung tumor. The excellent performance of our proposed model for PET-CT image co-segmentation of the lung tumor is demonstrated by comparing it to the state-of-art models.

Diffusing Capacity and Mortality in Chronic Obstructive Pulmonary Disease.

Rationale: Chronic obstructive pulmonary disease (COPD) mortality risk is often estimated using the BODE (body mass index, obstruction, dyspnea, exercise capacity) index, including body mass index, forced expiratory volume in 1 second, dyspnea score, and 6-minute walk distance. Diffusing capacity of the lung for carbon monoxide (DlCO) is a potential predictor of mortality that reflects physiology distinct from that in the BODE index. Objectives: This study evaluated DlCO as a predictor of mortality using participants from the COPDGene study. Methods: We performed time-to-event analyses of individuals with COPD (former or current smokers with forced expiratory volume in 1 second/forced vital capacity < 0.7) and DlCO measurements from the COPDGene phase 2 visit. Cox proportional hazard methods were used to model survival, adjusting for age, sex, pack-years, smoking status, BODE index, computed tomography (CT) percent emphysema (low attenuation areas below -950 Hounsfield units), CT airway wall thickness, and history of cardiovascular or kidney diseases. C statistics for models with DlCO and BODE scores were used to compare discriminative accuracy. Results: Of 2,329 participants, 393 (16.8%) died during the follow-up period (median = 4.9 yr). In adjusted analyses, for every 10% decrease in DlCO percent predicted, mortality increased by 28% (hazard ratio = 1.28; 95% confidence interval, 1.17-1.41, P < 0.001). When compared with other clinical predictors, DlCO percent predicted performed similarly to BODE (C statistic DlCO = 0.68; BODE = 0.70), and the addition of DlCO to BODE improved its discriminative accuracy (C statistic = 0.71). Conclusions: Diffusing capacity, a measure of gas transfer, strongly predicted all-cause mortality in individuals with COPD, independent of BODE index and CT evidence of emphysema and airway wall thickness. These findings support inclusion of DlCO in prognostic models for COPD.

A hidden infection: Racemose neurocysticercosis causing hydrocephalus; a case report

Introduction and importanceNeurocysticercosis (NCC) is the most common helminthic central nervous system infection (CNS) in the Western hemisphere and the most common cause of acquired epilepsy worldwide. Due to its relatively prolonged latent period and clinical similarity to other infectious diseases – including bacterial or viral meningitis and other helminthic infections – NCC may be difficult to diagnose, especially for clinicians who rarely encounter it.Case presentationThis case report discusses a patient with obstructive hydrocephalus and eosinophilic meningitis secondary to racemose NCC. The diagnosis process was initially complicated by the patient's history of pork allergy and absence of radiographic evidence of helminthic CNS infection. Further investigation showed a 4th ventricle multi-cystic lesion causing hydrocephalus which prompted a surgical intervention with a ventriculoperitoneal shunt (VPS) in conjunction with anti-helminthic medical treatment. At 1-year follow-up, the patient has reported recurrence of VPS related complications.Clinical discussionLarval cysts typically deposit within the brain parenchyma, making them easily detected on head computed tomography (CT) scans and leading to neurologic sequelae such as epilepsy. In this case, the absence of CT evidence of NCC and the patient's lifelong history of pork allergy slowed the diagnosis process.ConclusionRacemose NCC is a rare subset of the disease in which cyst clusters occupy the extra parenchymal space, thereby changing the symptomatic profile and making the cysts more difficult to visualize in imaging studies. In this case, magnetic resonance imaging (MRI) was the best imaging modality to diagnosis extra parenchymal NCC and guide its surgical management.

Abstract WP96: Computed Tomography Identifies Patients At High Risk For Stroke After Transient Ischemic Attack Or Non Disabling Stroke. A Prospective, Multicenter Validation Study

Background and Objectives: CT findings of acute and chronic ischemia are associated with stroke risk. We sought to validate these associations in a large prospective cohort of patients with TIA or minor stroke. Methods: We included prospectively enrolled emergency department patients from 13 centers with a final ED diagnosis of TIA or non-disabling stroke who had a computed tomography (CT) within 24 hours. Primary outcome was stroke within 90 days. Secondary outcomes were stroke within 2 or 7 days. CT findings were abstracted from the radiology report and classified for the presence of acute ischemia, chronic ischemia or microangiopathy. Multivariable logistic regression was used to test associations with primary and secondary endpoints. Results: In total 8,670 patients were enrolled between May 2010 to May 2017 and 8,382 had a CT within 24 hours. 4,547 patients had evidence of acute ischemia, chronic ischemia, or microangiopathy on CT imaging, of whom 175 had a subsequent stroke within 90 days (3.8% subsequent stroke rate; OR, 2.33; 95% CI, 1.62-3.36; P&lt;0.001). Findings associated with an increased risk of stroke at 90 days were acute ischemia alone (6.0%; OR, 2.42; 95% CI, 1.03-5.66; P=0.04), acute ischemia with microangiopathy (10.7%; OR, 3.34; 95% CI, 1.57-7.14; P=0.002), chronic ischemia with microangiopathy (5.2%; OR, 1.83; 95% CI, 1.34-2.50; P&lt;0.001), and acute ischemia with chronic ischemia and microangiopathy (10.9%; OR; 3.49; 95% CI, 1.54-7.91; P=0.003). ). Acute ischemia with chronic ischemia and microangiopathy were most strongly associated with increased risk of subsequent stroke within 2 days (OR, 4.36; 95% CI 1.31-14.54), and 7 days (OR, 4.50; 95%CI, 1.73-11.69). Conclusion: In patients with TIA or non-disabling stroke, CT evidence of acute ischemia with chronic ischemia and/or microangiopathy significantly increases the risk of subsequent stroke within 90 days of index visit. The combination of all 3 findings results in the greatest early risk.

Acoustic pulse thrombolysis complemented by ECMO improved survival in patients with high-risk pulmonary embolism.

The optimal treatment of high-risk pulmonary embolism (PE) with cardiac arrest is still controversial although various treatment approaches have been developed and improved. Here, we present a serie of patients with high-risk PE showing hemodynamic collapse, who were successfully treated with extracorporeal membrane oxygenation (ECMO) as an adjunct to EKOS™ acoustic pulse thrombolysis (APT). From April 2016 to June 2020, 29 patients with high-risk PE with cardiac arrest were retrospectively included. The mean age was 55.3 ± 9.2 years. A total of 12 (41.3%) patients were female. All patients had cardiac arrest, either as an initial presentation or in-hospital after presentation. All patients exhibited acute symptoms, computed tomography evidence of large thrombus burden, and severe right ventricular dysfunction. Primary outcome was all-cause 30-day mortality. Twenty-two patients survived to hospital discharge, with a mean intensive care unit stay of 9.9 ± 1.6 days (range: 7-22 days) and mean length of hospital stay of 23.7 ± 8.5 days (range: 11-44 days). Six patients died from refractory shock. Ninety-day mortality was 24.1% (7/29). The Mean ECMO duration was 3.5 ± 1.1 days and the mean RV/LV ratio decreased from 1.31 ± 0.17 to 0.92 ± 0.11 in patients who survived to discharge. The mean tissue plasminogen activator dose for survivor patients was 20.5 ± 1.6 mg. Patients with high-risk pulmonary embolism who suffer a cardiac arrest have high morbidity and mortality. APT complemented by ECMO could be a successful treatment option for the patients who have high-risk PE with circulatory collapse.

Current Standards for and Clinical Impact of Emergency Radiology in Major Trauma.

In industrialized countries, high energy trauma represents the leading cause of death and disability among people under 35 years of age. The two leading causes of mortality are neurological injuries and bleeding. Clinical evaluation is often unreliable in determining if, when and where injuries should be treated. Traditionally, surgery was the mainstay for assessment of injuries but advances in imaging techniques, particularly in computed tomography (CT), have contributed in progressively changing the classic clinical paradigm for major traumas, better defining the indications for surgery. Actually, the vast majority of traumas are now treated nonoperatively with a significant reduction in morbidity and mortality compared to the past. In this sense, another crucial point is the advent of interventional radiology (IR) in the treatment of vascular injuries after blunt trauma. IR enables the most effective nonoperative treatment of all vascular injuries. Indications for IR depend on the CT evidence of vascular injuries and, therefore, a robust CT protocol and the radiologist’s expertise are crucial. Emergency and IR radiologists form an integral part of the trauma team and are crucial for tailored management of traumatic injuries.

Microvascular injuries, secondary edema, and inconsistencies in lung vascularization between affected and nonaffected pulmonary segments of non-critically ill hospitalized COVID-19 patients presenting with clinical deterioration.

Purpose:We aimed to better understand the pathophysiology of SARS-CoV-2 pneumonia in non-critically ill hospitalized patients secondarily presenting with clinical deterioration and increase in oxygen requirement without any identified worsening factors.Methods:We consecutively enrolled patients without clinical or biological evidence for superinfection, without left ventricular dysfunction and for whom a pulmonary embolism was discarded by computed tomography (CT) pulmonary angiography. We investigated lung ventilation and perfusion (LVP) by LVP scintigraphy, and, 24 h later, left and right ventricular function by Tc-99m-labeled albumin-gated blood-pool scintigraphy with late (60 mn) tomographic albumin images on the lungs to evaluate lung albumin retention that could indicate microvascular injuries with secondary edema.Results:We included 20 patients with confirmed SARS-CoV-2 pneumonia. All had CT evidence of organizing pneumonia and normal left ventricular ejection fraction. No patient demonstrated preserved ventilation with perfusion defect (mismatch), which may discard a distal lung thrombosis. Patterns of ventilation and perfusion were heterogeneous in seven patients (35%) with healthy lung segments presenting a relative paradoxical hypoperfusion and hypoventilation compared with segments with organizing pneumonia presenting a relative enhancement in perfusion and preserved ventilation. Lung albumin retention in area of organizing pneumonia was observed in 12 patients (60%), indicating microvascular injuries, increase in vessel permeability, and secondary edema.Conclusion:In hospitalized non-critically ill patients without evidence of superinfection, pulmonary embolism, or cardiac dysfunction, various types of damage may contribute to clinical deterioration including microvascular injuries and secondary edema, inconsistencies in lung segments vascularization suggesting a dysregulation of the balance in perfusion between segments affected by COVID-19 and others.Summary Statement Microvascular injuries and dysregulation of the balance in perfusion between segments affected by COVID-19 and others are present in non-critically ill patients without other known aggravating factors. Key ResultsIn non-critically ill patients without evidence of superinfection, pulmonary embolism, macroscopic distal thrombosis or cardiac dysfunction, various types of damage may contribute to clinical deterioration including 1/ microvascular injuries and secondary edema, 2/ inconsistencies in lung segments vascularization with hypervascularization of consolidated segments contrasting with hypoperfusion of not affected segments, suggesting a dysregulation of the balance in perfusion between segments affected by COVID-19 and others.

EVALUATING THE EFFICACY OF HUMAN BRONCHIECTASISBASED ANTIBIOTIC THERAPY IN THE TREATMENT OF ORANGUTAN RESPIRATORY DISEASE SYNDROME.

Unique among apes, orangutans (Pongo spp.) develop a chronic respiratory disease called orangutan respiratory disease syndrome (ORDS). The authors define ORDS as intermittent bacterial infection and chronic inflammation of any region or combination of regions of the respiratory tract, including the sinuses, air sacs, cranial bones, airways, and lung parenchyma. Infection in any of these areas can present acutely but then becomes recurrent, chronic, progressive, and ultimately fatal. The closest model to this disease is cystic fibrosis (CF) in people. We hypothesized that use of a 4-8-wk course of combined oral antibiotics used in the treatment of bronchiectasis in CF patients would lead to prolonged symptomatic and computed tomography (CT) scan improvement in orangutans experiencing early signs of ORDS. Nine adult Bornean orangutans (Pongo pygmaeus, eight males, one female, 18-29 yr of age) diagnosed with early ORDS-like respiratory disease underwent CT scan before initiation of treatment. Each animal received a combined course of azithromycin (400 mg 3/wk, mean 7 mg/kg) and levofloxacin (500 mg PO q24h, mean 8.75 mg/kg) for a period of 4-8 wk. CT scan was repeated 6-14 mon after completion of antibiotic treatment. Pretreatment CT showed that six of nine animals had lower respiratory pathology (airway disease, pneumonia, or both). All six orangutans had concurrent sinusitis, mastoiditis, airsacculitis, or a combination of these conditions. Upper respiratory disease alone was observed in three animals. CT showed improvement or resolution in four of five sinusitis cases, improvement in one of two instances of mastoiditis, resolution in five of six instances of airsacculitis, improvement or resolution in six of six instance of lower airway disease (P = 0.03, 95% CI 0.54-1.0], and resolution in five of five cases of pneumonia. Resolution of pretreatment clinical signs was observed in all nine animals. Two developed signs not present at pretreatment. These results show that combination antibiotic therapy with azithromycin and levofloxacin provides improvement in clinical signs and CT evidence of ORDS-related pathology, resulting in symptom-free status in some animals for up to 33 mon.

Appendiceal Intraluminal Gas: A CT Marker for Gangrenous Appendicitis.

Introduction This manuscript aims to investigate the amount of intraluminal gas in acute, nonperforated appendicitis identified on computed tomography (CT) in diagnosing gangrenous appendicitis. Methods This is a retrospective observational, case-control study with consecutive data collected at a tertiary institution over a two-year period, of patients with CT-diagnosed acute appendicitis who subsequently went on for surgery within 48 hours. Patients who were less than 16 years old, who had an interval between CT and surgery of more than 48 hours, or with CT evidence of appendiceal perforation were excluded. Images were independently assessed by 3 radiologists for intraluminal gas, and the results were then correlated with reference standards obtained from surgical and histopathology reports for the diagnosis of nongangrenous versus gangrenous appendicitis. The sensitivity, specificity, and predictive values of CT intraluminal gas in gangrenous appendicitis were calculated. Results Our study identified 93 patients with nonperforated acute appendicitis who underwent surgery within the stated timeframe. Intraluminal gas in the appendix was identified in 26 patients (28%), of which 54% had macroscopic and/or microscopic evidence of gangrenous appendicitis. This is in contrast to the subgroup of patients who did not have intraluminal gas (72%), of which only 33% had gangrenous appendicitis. The specificity of intraluminal gas for gangrenous appendicitis is 79%, with a negative predictive value of 86% and likelihood ratio of 1.85. Conclusion In cases of established acute appendicitis, the presence of intraluminal gas is a moderately specific sign for gangrenous complication. This is worth reporting as it can help prognosticate and triage patients accordingly, for a timelier surgical management and a better outcome.

TP10.2.10A Prospective Analysis of Imaging Modalities in Appendicitis during the COVID-19 Pandemic

AimsAcute appendicitis is a common general surgical emergency, occurring in 90-100 per 100,000 patients per year. Clinical practice in the UK involves either a clinical or ultrasound (US) diagnosis, with computed tomography (CT) reserved for cases of suspected complicated appendicitis. Due to the COVID-19 pandemic management pathways were altered, this study sought to capture that.MethodsThis prospective study included adult patients with suspected appendicitis at a single UK centre from March-June 2020. The primary outcome measures were rates of US and CT imaging. Secondary outcomes included subsequent operative and histological findings.ResultsSeventy-five patients were included. A clinical diagnosis of appendicitis was made in 11 (15%). Thirty-five (47%) patients had CT, 22 (29%) had an US and 7 (9%) had both. The appendix was visualised in only 10 patients and a radiological diagnosis of appendicitis was made in 6 cases. Appendicitis was confirmed on histology in 67% of subsequently operated cases.CT evidence of appendicitis correlated with operative appendicitis in 93% (28/30) of cases. There were two cases of appendiceal malignancy not demonstrated on CT. Correlation of complicated appendicitis between CT and operative findings was poor; one third (10/28) of patients had appendiceal perforation not identified on CT.ConclusionsThe use of CT for diagnosing appendicitis was markedly increased during the first wave of the pandemic. The appendix was visualised infrequently on ultrasound, but when seen correlated well with histological findings. CT was superior at detecting appendicitis but failed to differentiate well between complicated and uncomplicated disease.

SP5.1.13 Upper gastrointestinal (UGI) mural thickening on Computed Tomography (CT) and its significance in the multi-disciplinary team (MDT) pathway

Abstract Aims Patients are frequently referred to the UGI MDT based on CT reported thickening of either the oesophagus, stomach or duodenum. We have sought to illustrate the efficacy of CT within the UGI cancer referral pathway. Method A retrospective analysis was carried out on patients referred to the UGI MDT at a University Teaching Hospital over a 22-month period. Patients referred with CT evidence of UGI tract thickening prior to endoscopy were included. CT findings were correlated with symptomatology, subsequent endoscopy and histology findings. Results 442 patients were referred to the UGI MDT between April 2014 and February 2016. 125 were referred for CT thickening alone (67 (53.2%) oesophageal, 49 (39.2%) gastric, 9 (7.2%) duodenal). 49 (39.2%) patients were subsequently diagnosed with UGI cancer, 57 (45.6%) had evidence of benign disease and 18 (14.4%) patients had no abnormality evident on endoscopy. CT thickening of 15mm and above was significantly more likely be malignant versus thickening less than 15mm [42/87 (48.3%) vs 7/38 (18.4%); p &amp;lt; 0.05]. Patients with thickening in the presence of a hiatus hernia were significantly less likely to have an associated cancer vs those without [3/26 (13%) vs 20/42 (51.1%); p &amp;lt; 0.05]. Conclusion We conclude that patients should not be referred for MDT opinion on CT evidence of UGI thickening alone. All patients should have an endoscopy prior to referral, particularly those with a hiatal hernia on CT. A high index of suspicion for malignancy should be adopted in patients with thickening greater than 15mm on imaging.

Shape-sensing robotic-assisted bronchoscopy for pulmonary nodules: initial multicenter experience using the Ion\u2122 Endoluminal System

BackgroundTraditional bronchoscopy provides limited approach to peripheral nodules. Shape-sensing robotic-assisted bronchoscopy (SSRAB, Ion™ Endoluminal System) is a new tool for minimally invasive peripheral nodule biopsy. We sought to answer the research question: Does SSRAB facilitate sampling of pulmonary nodules during bronchoscopists’ initial experience?MethodsThe lead-in stage of a multicenter, single-arm, prospective evaluation of the Ion Endoluminal System (PRECIsE) is described. Enrolled subjects ≥ 18 years old had recent computed tomography evidence of one or more solid or semi-solid pulmonary nodules ≥ 1.0 to ≤ 3.5 cm in greatest dimension and in any part of the lung. Subjects were followed at 10- and 30-days post-procedure. This stage provided investigators and staff their first human experience with the SSRAB system; safety and procedure outcomes were analyzed descriptively. Neither diagnostic yield nor sensitivity for malignancy were assessed in this stage. Categorical variables are summarized by percentage; continuous variables are summarized by median/interquartile range (IQR).ResultsSixty subjects were enrolled across 6 hospitals; 67 nodules were targeted for biopsy. Median axial, coronal and sagittal diameters were < 18 mm with a largest cardinal diameter of 20.0 mm. Most nodules were extraluminal and distance from the outer edge of the nodule to the pleura or nearest fissure was 4.0 mm (IQR: 0.0, 15.0). Median bronchial generation count to the target location was 7.0 (IQR: 6.0, 8.0). Procedure duration (catheter-in to catheter-out) was 66.5 min (IQR: 50.0, 85.5). Distance from the catheter tip to the closest edge of the virtual nodule was 7.0 mm (IQR: 2.0, 12.0). Biopsy completion was 97.0%. No pneumothorax or airway bleeding of any grade was reported.ConclusionsBronchoscopists leveraged the Ion SSRAB’s functionality to drive the catheter safely in close proximity of the virtual target and to obtain biopsies. This initial, multicenter experience is encouraging, suggesting that SSRAB may play a role in the management of pulmonary nodules.Clinical Trial Registration identifier and date NCT03893539; 28/03/2019.

790 Upper Gastrointestinal (UGI) Mural Thickening on Computed Tomography (CT) and its Significance in The Multi-Disciplinary Team (MDT) Pathway

Abstract Aim Patients are frequently referred to the UGI MDT based on CT reported thickening of either the oesophagus, stomach, or duodenum. We have sought to illustrate the efficacy of CT within the UGI cancer referral pathway. Method A retrospective analysis was carried out on patients referred to the UGI MDT at a University Teaching Hospital over a 22-month period. Patients referred with CT evidence of UGI tract thickening prior to endoscopy were included. CT findings were correlated with symptomatology, subsequent endoscopy, and histology findings. Results 442 patients were referred to the UGI MDT between April 2014 and February 2016. 125 were referred for CT thickening alone (67 (53.2%) oesophageal, 49 (39.2%) gastric, 9 (7.2%) duodenal). 49 (39.2%) patients were subsequently diagnosed with UGI cancer, 57 (45.6%) had evidence of benign disease and 18 (14.4%) patients had no abnormality evident on endoscopy. CT thickening of 15mm and above was significantly more likely be malignant versus thickening less than 15mm [42/87 (48.3%) vs 7/38 (18.4%); p &amp;lt; 0.05]. Patients with thickening in the presence of a hiatus hernia were significantly less likely to have an associated cancer vs those without [3/26 (13%) vs 20/42 (51.1%); p &amp;lt; 0.05]. Conclusions We conclude that patients should not be referred for MDT opinion on CT evidence of UGI thickening alone. All patients should have an endoscopy prior to referral, particularly those with a hiatal hernia on CT. A high index of suspicion for malignancy should be adopted in patients with thickening greater than 15mm on imaging.