Enhancing paranasal sinus disease detection with AutoML: efficient AI development and evaluation via magnetic resonance imaging

PURPOSE

Artificial intelligence (AI) in the form of automated machine learning (AutoML) offers a new potential breakthrough to overcome the barrier of entry for non-technically trained physicians. A Clinical Decision Support System (CDSS) for screening purposes using AutoML could be beneficial to ease the clinical burden in the radiological workflow for paranasal sinus diseases.

METHODS

The main target of this work was the usage of automated evaluation of model performance and the feasibility of the Vertex AI image classification model on the Google Cloud AutoML platform to be trained to automatically classify the presence or absence of sinonasal disease. The dataset is a consensus labelled Open Access Series of Imaging Studies (OASIS-3) MRI head dataset by three specialised head and neck consultant radiologists. A total of 1313 unique non-TSE T2w MRI head sessions were used from the OASIS-3 repository.

RESULTS

The best-performing image classification model achieved a precision of 0.928. Demonstrating the feasibility and high performance of the Vertex AI image classification model to automatically detect the presence or absence of sinonasal disease on MRI.

CONCLUSION

AutoML allows for potential deployment to optimise diagnostic radiology workflows and lay the foundation for further AI research in radiology and otolaryngology. The usage of AutoML could serve as a formal requirement for a feasibility study.

Parakinesia Brachialis Oscitans in a Patient With a First Manifestation of Multiple Sclerosis

Objectives

Parakinesia brachialis oscitans (PBO) is the involuntary movement of an otherwise paretic upper limb triggered by yawning. We describe the first case of PBO in a patient with a first manifestation of tumefactive multiple sclerosis (MS).

Methods

A 35-year-old man presented to the emergency department with a first episode of generalized seizure. Neurologic examination revealed left-sided spastic hemiparesis, predominantly affecting his upper limb. Brain MRI showed a tumefactive right hemisphere lesion consistent with demyelination. CSF did not document unmatched oligoclonal bands.

Results

Two weeks after admission and, despite being unable to voluntarily raise his left arm, the patient noticed a repeated and reproducible involuntary raise of this limb upon yawning, consistent with PBO. In the following weeks, the phenomenon diminished both in frequency and movement amplitude alongside motor recovery. An MRI performed 2 months later showed progression of the demyelinating lesion load and confirmed a diagnosis of MS.

Discussion

PBO is an example of autonomic voluntary motor dissociation and reflects the interplay between loss of cortical inhibition of the cerebellum in the setting of functional spinocerebellar pathways. Clinicians should be aware of this transient phenomenon which should not be mistaken as a chronic movement disorder or focal epileptic seizures.

Disease activity 4.5 years after starting cladribine: experience in 264 patients with multiple sclerosis

Background

Cladribine is an effective immunotherapy for people with multiple sclerosis (pwMS). Whilst most pwMS do not require re-treatment following standard dosing (two treatment courses), disease activity re-emerges in others. The characteristics of pwMS developing re-emerging disease activity remain incompletely understood.

Objectives

To explore whether clinical and/or paraclinical baseline characteristics, including the degree of lymphocyte reduction, drug dose and lesions on magnetic resonance imaging (MRI) are associated with re-emerging disease activity.

Design

Service evaluation in pwMS undergoing subcutaneous cladribine (SClad) treatment.

Methods

Demographics, clinical, laboratory and MRI data of pwMS receiving two courses of SClad were extracted from health records. To assess associations of predictor variables with re-emerging disease activity, a series of Cox proportional hazards models was fitted (one for each predictor variable).

Results

Of n = 264 pwMS 236 received two courses of SClad and were included in the analysis. Median follow-up was 4.5 years (3.9, 5.3) from the first, and 3.5 years (2.9, 4.3) from the last SClad administration. Re-emerging disease activity occurred in 57/236 pwMS (24%); 22/236 received further cladribine doses (SClad or cladribine tablets) at 36.7 months [median; interquartile range (IQR): 31.7, 42.1], and 22/236 other immunotherapies 18.9 months (13.0, 30.2) after their second course of SClad, respectively. Eligibility was based on MRI activity in 29, relapse in 5, both in 13, elevated cerebrospinal fluid neurofilament light chain level in 3, deterioration unrelated to relapse in 4 and other in 3. Only 36/57 of those eligible for additional immunotherapy had received a reduced dose of SClad for their second treatment course. Association was detected between re-emerging disease activity and (i) high baseline MRI activity and (ii) low second dose of SClad.

Conclusion

Re-emerging disease activity was associated with baseline MRI activity and low dose second course of SClad.

Diverse imaging features of adolescent glioblastoma

We highlight an unusual case of multifocal glioblastoma in an adolescent patient, manifesting as four discrete brain lesions, each distinct in appearance. Familiarity with the diverse imaging features of glioblastoma can reduce misdiagnosis and avoid treatment delays.

Concurrent thyrolipomatosis and thymolipoma in a patient with myasthenia gravis: a case report and review of the literature

We present a case of a man with a background of myasthenia gravis who presented with a neck lump, which was diagnosed as thyrolipomatosis in continuity with a very large thymolipoma. Following removal of these lesions, the patient's myaesthenic symptoms improved. While thymolipomas are often seen in the context of myasthenia gravis, thyrolipomatosis is a rare entity and to our knowledge the concurrent finding of both lesions with myasthenia gravis has never been reported. We highlight the important imaging features of both entities and the clinical importance of recognising them.

Social and Clinical Determinants of COVID-19 Outcomes: Modeling Real-World Data from a Pandemic Epicenter

IMPORTANCE

As the United States continues to accumulate COVID-19 cases and deaths, and disparities persist, defining the impact of risk factors for poor outcomes across patient groups is imperative.

OBJECTIVE

Our objective is to use real-world healthcare data to quantify the impact of demographic, clinical, and social determinants associated with adverse COVID-19 outcomes, to identify high-risk scenarios and dynamics of risk among racial and ethnic groups.

DESIGN

A retrospective cohort of COVID-19 patients diagnosed between March 1 and August 20, 2020. Fully adjusted logistical regression models for hospitalization, severe disease and mortality outcomes across 1-the entire cohort and 2- within self-reported race/ethnicity groups.

SETTING

Three sites of the NewYork-Presbyterian health care system serving all boroughs of New York City. Data was obtained through automated data abstraction from electronic medical records.

PARTICIPANTS

During the study timeframe, 110,498 individuals were tested for SARS-CoV-2 in the NewYork-Presbyterian health care system; 11,930 patients were confirmed for COVID-19 by RT-PCR or covid-19 clinical diagnosis.

MAIN OUTCOMES AND MEASURES

The predictors of interest were patient race/ethnicity, and covariates included demographics, comorbidities, and census tract neighborhood socio-economic status. The outcomes of interest were COVID-19 hospitalization, severe disease, and death.

RESULTS

Of confirmed COVID-19 patients, 4,895 were hospitalized, 1,070 developed severe disease and 1,654 suffered COVID-19 related death. Clinical factors had stronger impacts than social determinants and several showed race-group specificities, which varied among outcomes. The most significant factors in our all-patients models included: age over 80 (OR=5.78, p= 2.29x10-24) and hypertension (OR=1.89, p=1.26x10-10) having the highest impact on hospitalization, while Type 2 Diabetes was associated with all three outcomes (hospitalization: OR=1.48, p=1.39x10-04; severe disease: OR=1.46, p=4.47x10-09; mortality: OR=1.27, p=0.001). In race-specific models, COPD increased risk of hospitalization only in Non-Hispanics (NH)-Whites (OR=2.70, p=0.009). Obesity (BMI 30+) showed race-specific risk with severe disease NH-Whites (OR=1.48, p=0.038) and NH-Blacks (OR=1.77, p=0.025). For mortality, Cancer was the only risk factor in Hispanics (OR=1.97, p=0.043), and heart failure was only a risk in NH-Asians (OR=2.62, p=0.001).

CONCLUSIONS AND RELEVANCE

Comorbidities were more influential on COVID-19 outcomes than social determinants, suggesting clinical factors are more predictive of adverse trajectory than social factors.

What's that smell? A pictorial review of the olfactory pathways and imaging assessment of the myriad pathologies that can affect them

The olfactory pathway is composed of peripheral sinonasal and central sensorineural components. The wide variety of different pathologies that can affect the olfactory pathway reflect this complex anatomical relationship. Localising olfactory pathology can present a challenge to the reporting radiologist. This imaging review will illustrate the normal anatomy of the olfactory system and describe a systematic approach to considering olfactory dysfunction. Key concepts in image interpretation will be demonstrated using examples of olfactory pathway pathologies.

Clinical evaluation of automated quantitative MRI reports for assessment of hippocampal sclerosis

OBJECTIVES

Hippocampal sclerosis (HS) is a common cause of temporal lobe epilepsy. Neuroradiological practice relies on visual assessment, but quantification of HS imaging biomarkers-hippocampal volume loss and T2 elevation-could improve detection. We tested whether quantitative measures, contextualised with normative data, improve rater accuracy and confidence.

METHODS

Quantitative reports (QReports) were generated for 43 individuals with epilepsy (mean age ± SD 40.0 ± 14.8 years, 22 men; 15 histologically unilateral HS; 5 bilateral; 23 MR-negative). Normative data was generated from 111 healthy individuals (age 40.0 ± 12.8 years, 52 men). Nine raters with different experience (neuroradiologists, trainees, and image analysts) assessed subjects' imaging with and without QReports. Raters assigned imaging normal, right, left, or bilateral HS. Confidence was rated on a 5-point scale.

RESULTS

Correct designation (normal/abnormal) was high and showed further trend-level improvement with QReports, from 87.5 to 92.5% (p = 0.07, effect size d = 0.69). Largest magnitude improvement (84.5 to 93.8%) was for image analysts (d = 0.87). For bilateral HS, QReports significantly improved overall accuracy, from 74.4 to 91.1% (p = 0.042, d = 0.7). Agreement with the correct diagnosis (kappa) tended to increase from 0.74 ('fair') to 0.86 ('excellent') with the report (p = 0.06, d = 0.81). Confidence increased when correctly assessing scans with the QReport (p < 0.001, η²_p = 0.945).

CONCLUSIONS

QReports of HS imaging biomarkers can improve rater accuracy and confidence, particularly in challenging bilateral cases. Improvements were seen across all raters, with large effect sizes, greatest for image analysts. These findings may have positive implications for clinical radiology services and justify further validation in larger groups.

KEY POINTS

• Quantification of imaging biomarkers for hippocampal sclerosis-volume loss and raised T2 signal-could improve clinical radiological detection in challenging cases. • Quantitative reports for individual patients, contextualised with normative reference data, improved diagnostic accuracy and confidence in a group of nine raters, in particular for bilateral HS cases. • We present a pre-use clinical validation of an automated imaging assessment tool to assist clinical radiology reporting of hippocampal sclerosis, which improves detection accuracy.

Towards a standard MRI protocol for multiple sclerosis across the UK

Multiple sclerosis is a chronic inflammatory demyelinating and degenerative disease of the central nervous system. It is the most common non-traumatic cause of chronic disability in young adults. An early and accurate diagnosis, and effective disease modifying treatment are key elements of optimum care for people with MS (pwMS). MRI has become a critical tool to confirm the presence of dissemination in space and time of lesions characteristic of inflammatory demyelination, a cornerstone of MS diagnosis, over and above exclusion of numerous differential diagnoses. In the modern era of early and highly effective DMT, follow-up of pwMS also relies heavily on MRI, to both confirm efficacy and for pharmacovigilance. Since criteria for MS rely heavily on MRI, an agreed standardized acquisition and reporting protocol enabling efficient and equitable application across the UK is desirable. Following a recent meeting of MS experts in London (UK), we make recommendations for a standardized UK MRI protocol that captures the diagnostic phase as well as monitoring for safety and treatment efficacy once the diagnosis is established. Our views take into account issues arising from the (repeated) use of contrast agents as well as the advent of (semi-) automated tools to further optimize disease monitoring in pwMS.

Clostridium difficile enteritis: diffuse small bowel radiological changes in a patient with abdominal sepsis

While imaging appearances of pseudomembranous colitis are commonly recognised, radiological manifestations of Clostridium difficile-associated enteritis are poorly understood which, combined with the rarity of this infection involving small bowel, makes establishing the correct diagnosis challenging. Therefore, in order to encourage awareness of readers, we present a case of C. difficile enteritis that manifested as abdominal sepsis complicating the postoperative period in a middle-aged woman with fistulating Crohn's disease and defunctioning ileostomy. Radiological appearances are described based on three consecutive CT studies performed 5 days prior to onset of symptoms, during the peak of enteritis, corresponding with the patient's clinical deterioration, and also 35 days later following treatment and resolution.

FLAIR* to visualize veins in white matter lesions: A new tool for the diagnosis of multiple sclerosis?

Objective

To explore the potential of a post-processing technique combining FLAIR and T₂* (FLAIR*) to distinguish between lesions caused by multiple sclerosis (MS) from cerebral small vessel disease (SVD) in a clinical setting.

Methods

FLAIR and T₂* head datasets acquired at 3T of 25 people with relapsing MS (pwRMS) and ten with pwSVD were used. After post-processing, FLAIR* maps were used to determine the proportion of white matter lesions (WML) showing the ‘vein in lesion’ sign (VIL), a characteristic histopathological feature of MS plaques. Sensitivity and specificity of MS diagnosis were examined on the basis of >45% VIL⁺ and >60% VIL⁺ WML, and compared with current dissemination in space (DIS) MRI criteria.

Results

All pwRMS had >45% VIL⁺ WML (range 58–100%) whilst in pwSVD the proportion of VIL⁺ WML was significantly lower (0–64%; mean 32±20%). Sensitivity based on >45% VIL⁺ was 100% and specificity 80% whilst with >60% VIL⁺ as the criterion, sensitivity was 96% and specificity 90%. DIS criteria had 96% sensitivity and 40% specificity.

Conclusion

FLAIR* enables VIL⁺ WML detection in a clinical setting, facilitating differentiation of MS from SVD based on brain MRI.

Key points

• FLAIR* in a clinical setting allows visualization of veins in white matter lesions.

• Significant proportions of MS lesions demonstrate a vein in lesion on MRI.

• Microangiopathic lesions demonstrate a lower proportion of intralesional veins than MS lesions.

• Intralesional vein-based criteria may complement current MRI criteria for MS diagnosis.

Reverse tapered vs. straight PTFE (Gore-Tex) grafts in dogs

Reversed Autogenous Saphenous Vein (RASV) remains the material of choice in infrainguinal arterial bypass. A characteristic of RASV not seen in other grafts is its reverse tapered (RT) configuration. The purpose of this study was to investigate this geometric configuration. Straight 6 mm PTFE (gore-tex) grafts (SG) and 4-7 mm reverse tapered PTFE (gore-tex) grafts (RTG) were both implanted in the aorto-iliac position in 16 mongrel dogs. Specimens of surviving dogs were examined by the usual methods. In terms of absolute patency, 9 of 14 RTG (64%) and 5 of 14 SG (36%) P = 0.05, anastomotic thrombus formation 6 of 14 (43%) RTG vs. 10 of 14 (71%) SG P = 0.05 and in midgraft thrombus deposition P = 0.025 the RTG performed significantly better than the SG. In light of these results and other considerations, the reverse tapered configuration merits clinical investigation with other materials and in other species.

Effects of prostacyclin injections and infusions on canine femoral hemodynamics

The use of prostacyclin (PGI2) infusions has been recommended in the management of patients with severe distal arteriopathy, who are not candidates for conventional bypass procedures. Further clarification regarding the route of administration and the optimal dose of this potent vasodilator, however, is needed before controlled clinical trials are initiated. We measured bilateral femoral arterial blood flow electromagnetically in seven anesthetized adult mongrel dogs. Systemic arterial pressure and cardiac output were also measured. Central venous and femoral arterial injections of PGI2 were administered in five doses ranging from 10(-4) to 10(0) micrograms X kg-1 to study the dose response. PGI2 was also infused intravenously and intra-arterially for 20 minutes at a dose of 10(-1) micrograms X kg-1 X min-1. Femoral arterial injections of PGI2 in doses from 10(-4) through 10(0) micrograms X kg-1 caused significant (p less than 0.05) and dose-dependent increases in ipsilateral femoral arterial blood flow. Intravenous injections of PGI2 caused no significant changes in the dose range from 10(-4) to 10(-2) micrograms X kg-1 but resulted in a significant (p less than 0.05) reduction in femoral arterial flow and systemic arterial pressure at doses of 10(-1) and 10(0) micrograms X kg-1. The femoral arterial infusion of PGI2 produced a significant and sustained increase in femoral arterial flow that was not observed during the intravenous infusion. Arterial pressure was unchanged with intra-arterial PGI2 but was significantly reduced during the intravenous infusion. The beneficial hemodynamic effects of intra-arterial PGI2 suggest that further clinical trials should employ this route of administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of prostacyclin on distribution of canine femoral blood flow

Prostacyclin (PGI2) has been used clinically in the treatment of ischemic peripheral vascular disease. While intravenous infusions have been reported to be beneficial, the preferred route of administration (intravenous or intraarterial) and the influence of PGI2 on distribution of femoral blood flow have yet to be established. Bilateral femoral arterial blood flow was measured electromagnetically in 10 anesthetized adult mongrel dogs. The distribution of femoral arterial blood flow (FAQ) to skin, muscle, bone, and arteriovenous anastomoses (AVA) was determined by using femoral intraarterial injections of radioactively labeled microspheres before, during, and 30 min after 20-min intravenous (n = 5) and intraarterial (n = 5) infusions of PGI2 at 0.1 microgram kg-1 min-1. Control FAQ was 76 +/- 15 (mean +/- SEM) ml/min and its distribution to skin, muscle, bone, and AVA was 13 +/- 3%, 43 +/- 8%, 17 +/- 4%, and 26 +/- 7%, respectively. Arterial pressure was 127 +/- 7 mm Hg. Intraarterial infusions of PGI2 significantly (P less than 0.05) increased FAQ to 240 +/- 43 ml/min which was sustained throughout the infusion. Distribution of FAQ to skin increased significantly (P less than 0.05) to 47 +/- 8%, while that to the muscle of the thigh decreased to 17 +/- 4% (P less than 0.05). During intravenous infusion of PGI2 at the same concentration, FAQ did not change significantly and its distribution remained unchanged; however, there was a significant (P less than 0.05) reduction in arterial pressure to 78 +/- 6 mm Hg. No significant changes occurred in cardiac output, pulmonary arterial pressure, arterial blood gases, paw or core body temperatures.(ABSTRACT TRUNCATED AT 250 WORDS)