Expanding utility of cardiac computed tomography in infective endocarditis: A contemporary review

There is increasing evidence on the utility of cardiac computed tomography (CCT) in infective endocarditis (IE) to investigate the valvular pathology, the extra-cardiac manifestations of IE and pre-operative planning. CCT can assist in the diagnosis of perivalvular complications, such as pseudoaneurysms and abscesses, and can help identify embolic events to the lungs or systemic vasculature. CCT has also been shown to be beneficial in the pre-operative planning of patients by delineating the coronary artery anatomy and the major cardiovascular structures in relation to the sternum. Finally, hybrid nuclear/computed tomography techniques have been shown to increase the diagnostic accuracy in prosthetic valve endocarditis. This manuscript aims to provide a contemporary update of the existing evidence base for the use of CCT in IE.

Catheter-based renal sympathetic nerve denervation on hypertension management outcomes

BACKGROUND

Renal sympathetic denervation (RSD) provides a minimally invasive interventional treatment modality for patients with resistant hypertension. However, the post-operative outcomes remain a key area of investigation since its earliest clinical trials.

AIM

To evaluate patient outcomes after RSD intervention among peer-reviewed patient cases.

METHODS

A systematic review of literature on MEDLINE, Google Scholar, and the Cochrane Database of Systematic Reviews for RSD case studies to assess post-operative hypertension readings and medical management.

RESULTS

Among 51 RSD cases, the post-operative RSD patients report an apparent reduction with a mean number of 3.1 antihypertensive medications. The mean systolic arterial blood pressure 1 year following RSD was 136.0 mmHg (95%CI: 118.7-153.3).

CONCLUSION

The apparent improvements in office systolic blood pressure after 12 month post-operative RSD can support the therapeutic potential of this intervention for blood pressure reduction. Additional studies which utilized a uniform methodology for blood pressure measurement can further support the findings of this systematic review.

Impact of X-radiation in the management of COVID-19 disease

Coronaviruses are a diverse group of viruses that infect both animals and humans. Even though the existence of coronavirus and its infection to humans is not new, the 2019-novel coronavirus (nCoV) caused a major burden to individuals and society i.e., anxiety, fear of infection, extreme competition for hospitalization, and more importantly financial liability. The nCoV infection/disease diagnosis was based on non-specific signs and symptoms, biochemical parameters, detection of the virus using reverse-transcription polymerase chain reaction (RT-PCR), and X-ray-based imaging. This review focuses on the consolidation of potentials of X-ray-based imaging modality [chest-X radiography (CXR) and chest computed tomography (CT)] and low-dose radiation therapy (LDRT) for screening, severity, and management of COVID-19 disease. Reported studies suggest that CXR contributed significantly toward initial rapid screening/diagnosis and CT- imaging to monitor the disease severity. The chest CT has high sensitivity up to 98% and low specificity for diagnosis and severity of COVID-19 disease compared to RT-PCR. Similarly, LDRT compliments drug therapy in the early recovery/Less hospital stays by maintaining the physiological parameters better than the drug therapy alone. All the results undoubtedly demonstrated the evidence that X-ray-based technology continues to evolve and play a significant role in human health care even during the pandemic.

Molecular imaging as a tool for evaluation of COVID-19 sequelae – A review of literature

Coronavirus disease 2019 (COVID-19) is caused by the novel viral pathogen, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 primarily involves the lungs. Nucleic acid testing based on reverse-transcription polymerase chain reaction of respiratory samples is the current gold standard for the diagnosis of SARS-CoV-2 infection. Imaging modalities have an established role in triaging, diagnosis, evaluation of disease severity, monitoring disease progression, extra-pulmonary involvement, and complications. As our understanding of the disease improves, there has been substantial evidence to highlight its potential for multi-systemic involvement and development of long-term sequelae. Molecular imaging techniques are highly sensitive, allowing non-invasive visualization of physiological or pathological processes at a cellular or molecular level with potential for detection of functional changes earlier than conventional radiological imaging. The purpose of this review article is to highlight the evolving role of molecular imaging in evaluation of COVID-19 sequelae. Though not ideal for diagnosis, the various modalities of molecular imaging play an important role in assessing pulmonary and extra-pulmonary sequelae of COVID-19. Perfusion imaging using single photon emission computed tomography fused with computed tomography (CT) can be utilized as a first-line imaging modality for COVID-19 related pulmonary embolism. ¹⁸F-fluorodeoxyglucose positron emission tomography (PET)/CT is a sensitive tool to detect multi-systemic inflammation, including myocardial and vascular inflammation. PET in conjunction with magnetic resonance imaging helps in better characterization of neurological sequelae of COVID-19. Despite the fact that the majority of published literature is retrospective in nature with limited sample sizes, it is clear that molecular imaging provides additional valuable information (complimentary to anatomical imaging) with semi-quantitative or quantitative parameters to define inflammatory burden and can be used to guide therapeutic strategies and assess response. However, widespread clinical applicability remains a challenge owing to longer image acquisition times and the need for adoption of infection control protocols.

Radiological review of rhinocerebral mucormycosis cases during the COVID-19 Pandemic: A single-center experience

Mucormycosis is caused by the fungi belonging to the order Mucorales and class Zygomycetes. The incidence of mucormycosis has increased with the onset of the severe acute respiratory syndrome coronavirus 2 infections leading to the coronavirus disease 2019 (COVID-19) pandemic. This rise is attributed to the use of immunosuppressive medication to treat COVID-19 infections. Authors have retrospectively collected data of our cases of mucormycosis diagnosed from April 2020 to April 2021 at our institute. A total of 20 patients with rhinocerebral mucormycosis were studied. Most of the study subjects were male patients (90%) and were of the age group 41-50 years. Most patients in the review had comorbidities (85%) with diabetes being the most common comorbidity. Para nasal sinuses were involved in all the cases. Involvement of the neck spaces was present in 60% of the cases. Involvement of the central nervous system was present in 80% of the cases. Orbital involvement was present in 90% of the cases. The authors reviewed the various imaging findings of mucormycosis on computed tomography and magnetic resonance imaging in this article.

Artificial intelligence technologies in nuclear medicine

The use of artificial intelligence plays a crucial role in developing precision medicine in nuclear medicine. Artificial intelligence refers to a field of computer science aimed at imitating the performance of tasks typically requiring human intelligence. From machine learning to generative adversarial networks, artificial intelligence automized the workflow of medical imaging. In this mini-review, we encapsulate artificial intelligence models and their use in nuclear medicine imaging workflow.

Tuberculosis conundrum - current and future scenarios: A proposed comprehensive approach combining laboratory, imaging, and computing advances

Tuberculosis (TB) remains a global threat, with the rise of multiple and extensively drug resistant TB posing additional challenges. The International health community has set various 5-yearly targets for TB elimination: mathematical modelling suggests that a 2050 target is feasible with a strategy combining better diagnostics, drugs, and vaccines to detect and treat both latent and active infection. The availability of rapid and highly sensitive diagnostic tools (Gene-Xpert, TB-Quick) will vastly facilitate population-level identification of TB (including rifampicin resistance and through it, multi-drug-resistant TB). Basic-research advances have illuminated molecular mechanisms in TB, including the protective role of Vitamin D. Also, Mycobacterium tuberculosis impairs the host immune response through epigenetic mechanisms (histone-binding modulation). Imaging will continue to be key, both for initial diagnosis and follow-up. We discuss advances in multiple imaging modalities to evaluate TB tissue changes, such as molecular imaging techniques (including pathogen-specific positron emission tomography imaging agents), non-invasive temporal monitoring, and computing enhancements to improve data acquisition and reduce scan times. Big data analysis and Artificial Intelligence (AI) algorithms, notably in the AI sub-field called “Deep Learning”, can potentially increase the speed and accuracy of diagnosis. Additionally, Federated learning makes multi-institutional/multi-city AI-based collaborations possible without sharing identifiable patient data. More powerful hardware designs - e.g., Edge and Quantum Computing- will facilitate the role of computing applications in TB. However, “Artificial Intelligence needs real Intelligence to guide it!” To have maximal impact, AI must use a holistic approach that incorporates time tested human wisdom gained over decades from the full gamut of TB, i.e., key imaging and clinical parameters, including prognostic indicators, plus bacterial and epidemiologic data. We propose a similar holistic approach at the level of national/international policy formulation and implementation, to enable effective culmination of TB’s endgame, summarizing it with the acronym “TB - REVISITED”.

Recent advances in imaging techniques of renal masses

Multiphasic multidetector computed tomography (CT) forms the mainstay for the characterization of renal masses whereas magnetic resonance imaging (MRI) acts as a problem-solving tool in some cases. However, a few of the renal masses remain indeterminate even after evaluation by conventional imaging methods. To overcome the deficiency in current imaging techniques, advanced imaging methods have been devised and are being tested. This review will cover the role of contrast-enhanced ultrasonography, shear wave elastography, dual-energy CT, perfusion CT, MR perfusion, diffusion-weighted MRI, blood oxygen level-dependent MRI, MR spectroscopy, positron emission tomography (PET)/prostate-specific membrane antigen-PET in the characterization of renal masses.

Evaluation of the dual vascular supply patterns in ground-glass nodules with a dynamic volume computed tomography

BACKGROUND

In recent years, the detection rate of ground-glass nodules (GGNs) has been improved dramatically due to the popularization of low-dose computed tomography (CT) screening with high-resolution CT technique. This presents challenges for the characterization and management of the GGNs, which depends on a thorough investigation and sufficient diagnostic knowledge of the GGNs. In most diagnostic studies of the GGNs, morphological manifestations are used to differentiate benignancy and malignancy. In contrast, few studies are dedicated to the assessment of the hemodynamics, i.e., perfusion parameters of the GGNs.

AIM

To assess the dual vascular supply patterns of GGNs on different histopathology and opacities.

METHODS

Forty-seven GGNs from 47 patients were prospectively included and underwent the dynamic volume CT. Histopathologic diagnoses were obtained within two weeks after the CT examination. Blood flow from the bronchial artery [bronchial flow (BF)] and pulmonary artery [pulmonary flow (PF)] as well as the perfusion index (PI) = [PF/(PF + BF)] were obtained using first-pass dual-input CT perfusion analysis and compared respectively between different histopathology and lesion types (pure or mixed GGNs) and correlated with the attenuation values of the lesions using one-way ANOVA, student’s t test and Pearson correlation analysis.

RESULTS

Of the 47 GGNs (mean diameter, 8.17 mm; range, 5.3-12.7 mm), 30 (64%) were carcinoma, 6 (13%) were atypical adenomatous hyperplasia and 11 (23%) were organizing pneumonia. All perfusion parameters (BF, PF and PI) demonstrated no significant difference among the three conditions (all P > 0.05). The PFs were higher than the BFs in all the three conditions (all P < 0.001). Of the 30 GGN carcinomas, 14 showed mixed GGNs and 16 pure GGNs with a higher PI in the latter (P < 0.01). Of the 17 benign GGNs, 4 showed mixed GGNs and 13 pure GGNs with no significant difference of the PI between the GGN types (P = 0.21). A negative correlation (r = -0.76, P < 0.001) was demonstrated between the CT attenuation values and the PIs in the 30 GGN carcinomas.

CONCLUSION

The GGNs are perfused dominantly by the PF regardless of its histopathology while the weight of the BF in the GGN carcinomas increases gradually during the progress of its opacification.

Comments on "Neonatal infratentorial subdural hematoma contributing to obstructive hydrocephalus in the setting of therapeutic cooling: A case report"

Although therapeutic hypothermia (TH) contributes significantly in the treatment of hypoxic ischemic encephalopathy (HIE), it could result in devastating complications such as intracranial hemorrhages. Laboratory examinations for possible coagulation disorders and early brain imaging can detect all these cases that are amenable to aggravation of HIE after the initiation of TH.

Do preoperative pancreatic computed tomography attenuation index and enhancement ratio predict pancreatic fistula after pancreaticoduodenectomy?

BACKGROUND

The commonly used predictors of clinically relevant postoperative pancreatic fistula (CR-POPF) following pancreaticoduodenectomy (PD) have subjective assessment components and can be used only in the postoperative setting. Also, the available objective predictors based on preoperative cross-sectional imaging were not prospectively studied.

AIM

To evaluate the accuracy of the pancreatic attenuation index (PAI) and pancreatic enhancement ratio (PER) for predicting CR-POPF following PD and its correlation with pancreatic fat fraction and fibrosis.

METHODS

A prospective observational study included patients who underwent PD for benign and malignant pathology of the periampullary region or pancreatic head between February 2019 and February 2021. Patients undergoing extended or total pancreatectomy and those with severe atrophy of pancreatic tissue or extensive parenchymal calcifications in the pancreatic head and neck precluding calculation of PAI and PER were excluded from the study. Preoperatively PAI was measured in the neck of the pancreas by marking regions of interest (ROI) in the non-contrast computed tomography (CT), and PER was measured during the contrast phase of the CT abdomen. Also, the fibrosis score and fat fraction of the pancreatic neck were assessed during the histopathological examination. Demographic, clinical and preoperative radiological indices (PAI, PER) were evaluated to predict CR-POPF. Preoperative pancreatic neck CT indices were correlated with the histopathological assessment of fat fraction and fibrosis.

RESULTS

Of the 70 patients who underwent PD, 61 patients fulfilling the inclusion criteria were included in the analysis. The incidence of CR-POPF was 29.5% (18/61). PAI had no association with the development of CR-POPF. Of the preoperative parameters, PER (mean ± standard deviation [SD]) was significantly lower in patients developing CR-POPF (0.58 ± 0.20 vs 0.81 ± 0.44, P = 0.006). The area under the curve for the PER was 0.661 (95%CI: 0.517-0.804), which was significant (P = 0.049). PER cut-off of 0.673 predicts CR-POPF with 77.8% sensitivity and 55.8% specificity. PAI and PER had a weak negative correlation (Strength-0.26, P = 0.037). Also, PER showed a moderately positive correlation with fibrosis (Strength 0.50, P < 0.001). Patients with CR-POPF had a significantly higher incidence of the intraabdominal abscess (50% vs 2.3%, P < 0.001), delayed gastric emptying (83.3% vs 30.2, P < 0.001), and prolonged mean (± SD) postoperative hospital stay (26.8 ± 13.9 vs 9.6 ± 3.6, P = 0.001).

CONCLUSION

PER exhibited good accuracy in predicting the development of CR-POPF. PER additionally showed a good correlation with PAI and fibrosis scores and may be used as an objective preoperative surrogate for assessing pancreatic texture. However, ROI-based PAI did not show any association with CR-POPF and pancreatic fat fraction.

Investigation of coronoid process hyperplasia using Levandoski analysis on panoramic radiographs

BACKGROUND

The diagnosis of coronoid process hyperplasia (CPH) is usually based on symptoms and radiological imaging. Because of its similar symptoms, it can be confused with temporomandibular joint diseases. Therefore, an objective and reproducible way of diagnosis should be determined.

AIM

To investigate CPH using Levandoski analysis on panoramic radiographs to determine its prevalence.

METHODS

A total of 300 panoramic radiograph images (600 coronoid processes) were examined. Having measured the Condyle-Gonion (Cd-Go) and Coronoid-Gonion (Cor-Go) distances, the Cor-Go:Cd-Go ratio was calculated for the left and right sides of each image.

RESULTS

There was a statistically significant difference in Cd-Go and Cor-Go distances between male and female participants (P < 0.001). There was no statistically significant relationship between Cor-Go:Cd-Go ratios and gender (P > 0.05).

CONCLUSION

Cd-Go and Cor-Go distances were statistically significantly increased in males on both the left and right sides. The ratio of Cor-Go:Cd-Go was preserved in both genders. The prevalence of CPH was found to be 0.3%.

Decreased cross-sectional muscle area in male patients with clear cell renal cell carcinoma and peritumoral collateral vessels

BACKGROUND

Sarcopenia is the loss of skeletal muscle mass (SMM) and is a sign of cancer cachexia. Patients with advanced renal cell carcinoma (RCC) may show cachexia.

AIM

To evaluate the amount of SMM in male clear cell RCC (ccRCC) patients with and without collateral vessels.

METHODS

In this study, we included a total of 124 male Caucasian patients divided into two groups: ccRCCa group without collateral vessels (n = 54) and ccRCCp group with collateral vessels (n = 70). Total abdominal muscle area (TAMA) was measured in both groups using a computed tomography imaging-based approach. TAMA measures were also corrected for age in order to rule out age-related effects.

RESULTS

There was a statistically significant difference between the two groups in terms of TAMA (P < 0.05) driven by a reduction in patients with peritumoral collateral vessels. The result was confirmed by repeating the analysis with values corrected for age (P < 0.05), indicating no age effect on our findings.

CONCLUSION

This study showed a decreased TAMA in ccRCC patients with peritumoral collateral vessels. The presence of peritumoral collateral vessels adjacent to ccRCC might be a fine diagnostic clue to sarcopenia.

Focal liver lesions in cirrhosis: Role of contrast-enhanced ultrasonography

Contrast-enhanced ultrasound (CEUS) represents a great innovation for the evaluation of focal liver lesions (FLLs). The main advantage of CEUS is the real-time imaging examination and the very low toxicity in patients with renal failure. Liver cirrhosis has been recognized as a major risk factor for the onset of hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). HCC in liver cirrhosis develops as the last step of a complex that leads to the gradual transformation from regenerative nodule through dysplastic nodule to HCC. In patients with liver cirrhosis, a surveillance program is recommended consisting of ultrasound (US) for detecting small focal lesions. A wide spectrum of benign and malignant lesions other than HCC may be found in the cirrhotic liver and their differentiation is important to avoid errors in staging diseases that may preclude potentially curative therapies. Several published studies have explored the value of CEUS in liver cirrhosis and they have been shown to have excellent diagnostic and prognostic performances for the evaluation of non-invasive and efficient diagnosis of FLLs in patients at high risk for liver malignancies. The purpose of this article is to describe and discuss CEUS imaging findings of FLLs including HCC and ICC, all of which occur in cirrhotic livers with varying prevalence.

Outcome of percutaneous drainage for septic complications coexisted with COVID-19

BACKGROUND

The resulting tissue hypoxia and increased inflammation secondary to severe coronavirus disease 2019 (COVID-19) combined with viral load, and other baseline risk factors contribute to an increased risk of severe sepsis or co-existed septic condition exaggeration.

AIM

To describe the clinical, radiological, and laboratory characteristics of a small cohort of patients infected by severe acute respiratory syndrome coronavirus 2 who underwent percutaneous drainage for septic complications and their post-procedural outcomes.

METHODS

This retrospective study consisted of 11 patients who were confirmed to have COVID-19 by RT-PCR test and required drain placement for septic complications. The mean age ± SD of the patients was 48.5 ± 14 years (range 30-72 years). Three patients underwent cholecystostomy for acute acalculous cholecystitis. Percutaneous drainage was performed in seven patients; two peripancreatic collections; two infected leaks after hepatic resection; one recurrent hepatic abscess, one psoas abscess and one lumbar abscess. One patient underwent a percutaneous nephrostomy for acute pyelonephritis.

RESULTS

Technical success was achieved in 100% of patients, while clinical success was achieved in 4 out of 11 patients (36.3%). Six patients (54.5%) died despite proper percutaneous drainage and adequate antibiotic coverage. One patient (9%) needed operative intervention. Two patients (18.2%) had two drainage procedures to drain multiple fluid collections. Two patients (18.2%) had repeat drainage procedures due to recurrent fluid collections. The average volume of the drained fluid immediately after tube insertion was 85 mL. Follow-up scans show a reduction of the retained content and associated inflammatory changes after tube insertion in all patients. There was no significant statistical difference (P = 0.6 and 0.4) between the mean of WBCs and neutrophils count before drainage and seven days after drainage. The lymphocyte count shows significant increased seven days after drainage (P = 0.03).

CONCLUSION

In this study, patients having septic complications associated with COVID-19 showed relatively poor clinical outcomes despite technically successful percutaneous drainage.

Follow-up computed tomography scan in post-COVID-19 pneumonia

The coronavirus disease 2019 (COVID-19) global pandemic can be a severe illness that leads to morbidity and mortality. With the increasing number of COVID-19 pneumonia survivors, several long-term changes may persist, including abnormal imaging of lung parenchyma. In addition to the clinical course, it is vital to follow up on pulmonary imaging during the post-infectious period, which is not routinely required in other common pulmonary diagnoses. Computed tomography (CT) scan of the chest is an effective and diagnostic tool for pneumonia which gives an insight into structural abnormalities within the lungs, complications, and possible progression of the disease. Several studies have monitored COVID-19 pneumonia and its complications using serial CT chest imaging from the initial phase of infection, hospitalization, and post-discharge. Nonetheless, long-term follow-up imaging data in post-COVID-19 is still limited. We have summarized the findings utilizing a systematic review of the literature regarding COVID-19 pneumonia imaging, including long-term follow-up.

Artificial intelligence in dentomaxillofacial radiology

Artificial intelligence (AI) has the potential to revolutionize healthcare and dentistry. Recently, there has been much interest in the development of AI applications. Dentomaxillofacial radiology (DMFR) is within the scope of these applications due to its compatibility with image processing methods. Classification and segmentation of teeth, automatic marking of anatomical structures and cephalometric analysis, determination of early dental diseases, gingival, periodontal diseases and evaluation of risk groups, diagnosis of certain diseases, such as; osteoporosis that can be detected in jaw radiographs are among studies conducted by using radiological images. Further research in the field of AI will make great contributions to DMFR. We aim to discuss most recent AI-based studies in the field of DMFR.

Immunosuppressive treatment and radiotherapy in kidney transplant patients: A systematic review

BACKGROUND

Immunosuppression (IS) therapy may contribute to cancer development. Some authors have proposed to reduce immunosuppression drugs dose in case of viral infections, in immunosuppression-related diseases, and in patients undergoing radiotherapy. The present analysis reports the results of a systematic review on kidney transplant recipients undergoing immunosuppression and radiotherapy.

AIM

To define if it is necessary reduce immunosuppression drugs during radiotherapy.

METHODS

The literature search was based on three electronic databases (Pubmed, Scopus, and Web of Science) using selected keywords linked through the "AND" and "OR" Boolean operators to build specific strings for each electronic search engine. Two researchers independently screened the citations, and disagreement was resolved by discussion or through the intervention of a third author. The review was conducted and reported according to the PRISMA statement. Extracted data were narratively synthesized, and, where possible, frequencies, percentages, and ranges were calculated.

RESULTS

The literature search resulted in 147 citations. After abstracts screening, 21 records were selected for full-text evaluation. Fifteen of these were excluded, leaving six papers considered suitable for analysis. There is still no clear evidence that withdrawing antimetabolites and/or calcineurin inhibitors and/or mammalian target of rapamycin-inhibitors, as opposed to continuing maintenance IS, improves patient survival in kidney transplant recipients with cancer undergoing radiotherapy. Only few retrospective studies on small cancer patient cohorts are available in this setting, but without comparison of different immunosuppression treatments. Even where immunosuppression therapy was described, patient survival seemed to be correlated only with cancer stage and type.

CONCLUSION

The results of this systematic review do not support the reduction of immunosuppression dose in patients undergoing radiotherapy.

Acute coronary syndrome on non-electrocardiogram-gated contrast-enhanced computed tomography

It is not rare for acute coronary syndrome (ACS) patients to present with symptoms that are atypical, rather than chest pain. It is sometimes difficult to achieve a definitive diagnosis of ACS for such patients who present with atypical symptoms, normal initial biomarkers of myocardial necrosis, and normal or nondiagnostic electrocardiograms (ECGs). Although cardiac CT allows for assessments of coronary artery stenosis as well as myocardial perfusion defect in patients with suspected ACS, it requires ECG gating and is usually performed with high-performance multislice CT for highly probable ACS patients. However, several recent reports have stated that ACS is detectable by myocardial perfusion defects even on routine non-ECG-gated contrast-enhanced CT. A growing number of contrast-enhanced CT scans are now being performed in emergency departments in search of pathologies responsible for a patient’s presenting symptoms. In order to avoid inappropriate management for this life-threatening event, clinicians should be aware that myocardial perfusion defect is more commonly detectable even on routine non-ECG-gated contrast-enhanced CT performed in search of other pathologies.

Diagnostic accuracy of thoracic imaging modalities for the detection of COVID-19

The ongoing coronavirus disease 2019 (COVID-19) pandemic continues to present diagnostic challenges. The use of thoracic radiography has been studied as a method to improve the diagnostic accuracy of COVID-19. The ‘Living’ Cochrane Systematic Review on the diagnostic accuracy of imaging tests for COVID-19 is continuously updated as new information becomes available for study. In the most recent version, published in March 2021, a meta-analysis was done to determine the pooled sensitivity and specificity of chest X-ray (CXR) and lung ultrasound (LUS) for the diagnosis of COVID-19. CXR gave a sensitivity of 80.6% (95%CI: 69.1-88.6) and a specificity of 71.5% (95%CI: 59.8-80.8). LUS gave a sensitivity rate of 86.4% (95%CI: 72.7-93.9) and specificity of 54.6% (95%CI: 35.3-72.6). These results differed from the findings reported in the recent article in this journal where they cited the previous versions of the study in which a meta-analysis for CXR and LUS could not be performed. Additionally, the article states that COVID-19 could not be distinguished, using chest computed tomography (CT), from other respiratory diseases. However, the latest review version identifies chest CT as having a specificity of 80.0% (95%CI: 74.9-84.3), which is much higher than the previous version which indicated a specificity of 61.1% (95%CI: 42.3-77.1). Therefore, CXR, chest CT and LUS have the potential to be used in conjunction with other methods in the diagnosis of COVID-19.

Comments on "Review of the role of diagnostic modalities and imaging findings in the COVID-19 pandemic"

The present letter to the editor corresponds to the article entitled “Comprehensive literature review on the radiographic findings, imaging modalities, and the role of radiology in the coronavirus disease 2019 (COVID-19) pandemic” by Pal et al, published in World J Radiol. 2021; 13(9): 258-282. With zero to unknown prevalence, COVID-19 has created a heterogeneous and unforeseen situation across the world. Healthcare providers encountered new challenges in image interpretation, characterization, and prognostication of the disease. Pal et al delineated the radiological findings, which would guide the radiologists to identify the early signs of severe infection.

Chest radiological finding of COVID-19 in patients with and without diabetes mellitus: Differences in imaging finding

The pandemic of novel coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Diabetes mellitus is a risk factor for developing severe illness and a leading cause of death in patients with COVID-19. Diabetes can precipitate hyperglycaemic emergencies and cause prolonged hospital admissions. Insulin resistance is thought to cause endothelial dysfunction, alveolar capillary micro-angiopathy and interstitial lung fibrosis through pro-inflammatory pathways. Autopsy studies have also demonstrated the presence of microvascular thrombi in affected sections of lung, which may be associated with diabetes. Chest imaging using x-ray (CXR) and computed tomography (CT) of chest is used to diagnose, assess disease progression and severity in COVID-19. This article reviews current literature regarding chest imaging findings in patients with diabetes affected by COVID-19. A literature search was performed on PubMed. Patients with diabetes infected with SARS-CoV-2 are likely to have more severe infective changes on CXR and CT chest imaging. Severity of airspace consolidation on CXR is associated with higher mortality, particularly in the presence of co-morbidities such as ischaemic heart disease. Poorly controlled diabetes is associated with more severe acute lung injury on CT. However, no association has been identified between poorly-controlled diabetes and the incidence of pulmonary thromboembolism in patients with COVID-19.

Incidental radiological findings suggestive of COVID-19 in asymptomatic patients

Despite routine screening of patients for coronavirus disease 2019 (COVID-19) symptoms and signs at hospital entrances, patients may slip between the cracks and be incidentally discovered to have lung findings that could indicate COVID-19 infection on imaging obtained for other reasons. Multiple case reports and case series have been published to identify the pattern of this highly infectious disease. This article addresses the radiographic findings in different imaging modalities that may be incidentally seen in asymptomatic patients who carry COVID-19. In general, findings of COVID-19 infection may appear in computed tomography (CT), magnetic resonance imaging, positron emission tomography-CT, ultrasound, or plain X-rays that show lung or only apical or basal cuts. The identification of these characteristics by radiologists and clinicians is crucial because this would help in the early recognition of cases so that a rapid treatment protocol can be established, the immediate isolation to reduce community transmission, and the organization of close monitoring. Thus, it is important to both the patient and the physician that these findings are highlighted and reported.

Effect of training on resident inter-reader agreement with American College of Radiology Thyroid Imaging Reporting and Data System

BACKGROUND

The American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) was introduced to standardize the ultrasound characterization of thyroid nodules. Studies have shown that ACR-TIRADS reduces unnecessary biopsies and improves consistency of imaging recommendations. Despite its widespread adoption, there are few studies to date assessing the inter-reader agreement amongst radiology trainees with limited ultrasound experience. We hypothesize that in PGY-4 radiology residents with no prior exposure to ACR TI-RADS, a statistically significant improvement in inter-reader reliability can be achieved with a one hour training session.

AIM

To evaluate the inter-reader agreement of radiology residents in using ACR TI-RADS before and after training.

METHODS

A single center retrospective cohort study evaluating 50 thyroid nodules in 40 patients of varying TI-RADS levels was performed. Reference standard TI-RADS scores were established through a consensus panel of three fellowship-trained staff radiologists with between 1 and 14 years of clinical experience each. Three PGY-4 radiology residents (trainees) were selected as blinded readers for this study. Each trainee had between 4 to 5 mo of designated ultrasound training. No trainee had received specialized TI-RADS training prior to this study. Each of the readers independently reviewed the 50 testing cases and assigned a TI-RADS score to each case before and after TI-RADS training performed 6 wk apart. Fleiss kappa was used to measure the pooled inter-reader agreement. The relative diagnostic performance of readers, pre- and post-training, when compared against the reference standard.

RESULTS

There were 33 females and 7 males with a mean age of 56.6 ± 13.6 years. The mean nodule size was 19 ± 14 mm (range from 5 to 63 mm). A statistically significant superior inter-reader agreement was found on the post-training assessment compared to the pre-training assessment for the following variables: 1. “Shape” (k of 0.09 [slight] pre-training vs 0.67 [substantial] post-training, P < 0.001), 2. “Echogenic foci” (k of 0.28 [fair] pre-training vs 0.45 [moderate] post-training, P = 0.004), 3. ‘TI-RADS level’ (k of 0.14 [slight] pre-training vs 0.36 [fair] post-training, P < 0.001) and 4. ‘Recommendations’ (k of 0.36 [fair] pre-training vs 0.50 [moderate] post-training, P = 0.02). No significant differences between the pre- and post-training assessments were found for the variables 'composition', 'echogenicity' and 'margins'. There was a general trend towards improved pooled sensitivity with TI-RADS levels 1 to 4 for the post-training assessment while the pooled specificity was relatively high (76.6%-96.8%) for all TI-RADS level.

CONCLUSION

Statistically significant improvement in inter-reader agreement in the assigning TI-RADS level and recommendations after training is observed. Our study supports the use of dedicated ACR TI-RADS training in radiology residents.

Prevalence of hypercoagulable states in stented thrombotic iliac vein compression syndrome with comparison of re-intervention and anticoagulation regimens

BACKGROUND

Endovascular therapy is playing an increasing role in the treatment of iliofemoral venous disease. Iliac stent patency is multifactorial, and current management is based on best clinical practices, varying by institution.

AIM

To evaluate how thrombophilia influences management and outcomes of patients who undergo venous stenting for thrombotic iliac vein compression syndromes.

METHODS

A retrospective observational analysis was performed on 65 patients with thrombotic iliac vein compression syndrome that underwent common iliac vein (CIV) stenting between December 2013 and December 2019 at a large academic center. Search criteria included CIV stenting and iliac vein compression. Non-thrombotic lesions and iliocaval thrombosis and/or occlusions were excluded. A total of 65 patients were selected for final analysis. Demographic information, procedural data points, and post-procedural management and outcomes were collected. Statistical analyses included Fisher's exact and Chi-square tests to compare discrete variables and the Wilcoxon rank-sum test to compare continuous variables between thrombophilia positive and negative patients.

RESULTS

65 patients underwent successful balloon angioplasty and CIV stenting. Of these patients, 33 (50.8%) underwent thrombophilia testing, with 16 (48.5%) testing positive. Stent patency on ultrasound did not significantly differ between thrombophilia positive and negative patients at 1 mo (92.3% vs 81.3%, P = 0.6), 6 mo (83.3% vs 80%, P > 0.9), or 12 mo (77.8% vs 76.9%, P = 0.8). Immediately after stent placement, thrombophilia patients were more likely to be placed on dual therapy (aspirin and anticoagulation) or triple therapy (aspirin, clopidogrel, and anticoagulation) (50% vs 41.2%, P > 0.9), and remain on dual therapy at 6 mo (25% vs 12.5%, P = 0.5) and 12 mo (25% vs 6.7%, P = 0.6). There was no significant difference in re-intervention rates (25% vs 35.3%, P = 0.7) or number of re-interventions (average 2.3 vs 1.3 per patient, P = 0.4) between thrombophilia positive and negative patients.

CONCLUSION

Half of patients with stented thrombotic iliac vein compression syndrome and thrombophilia testing were positive. The presence of thrombophilia did not significantly impact stent patency or re-intervention rates.