External Validation of Robust Radiomic Signature to Predict 2-Year Overall Survival in Non-Small-Cell Lung Cancer

Lung cancer is the second most fatal disease worldwide. In the last few years, radiomics is being explored to develop prediction models for various clinical endpoints in lung cancer. However, the robustness of radiomic features is under question and has been identified as one of the roadblocks in the implementation of a radiomic-based prediction model in the clinic. Many past studies have suggested identifying the robust radiomic feature to develop a prediction model. In our earlier study, we identified robust radiomic features for prediction model development. The objective of this study was to develop and validate the robust radiomic signatures for predicting 2-year overall survival in non-small cell lung cancer (NSCLC). This retrospective study included a cohort of 300 stage I-IV NSCLC patients. Institutional 200 patients' data were included for training and internal validation and 100 patients' data from The Cancer Image Archive (TCIA) open-source image repository for external validation. Radiomic features were extracted from the CT images of both cohorts. The feature selection was performed using hierarchical clustering, a Chi-squared test, and recursive feature elimination (RFE). In total, six prediction models were developed using random forest (RF-Model-O, RF-Model-B), gradient boosting (GB-Model-O, GB-Model-B), and support vector(SV-Model-O, SV-Model-B) classifiers to predict 2-year overall survival (OS) on original data as well as balanced data. Model validation was performed using 10-fold cross-validation, internal validation, and external validation. Using a multistep feature selection method, the overall top 10 features were chosen. On internal validation, the two random forest models (RF-Model-O, RF-Model-B) displayed the highest accuracy; their scores on the original and balanced datasets were 0.81 and 0.77 respectively. During external validation, both the random forest models' accuracy was 0.68. In our study, robust radiomic features showed promising predictive performance to predict 2-year overall survival in NSCLC.

Emerging role of quantitative imaging (radiomics) and artificial intelligence in precision oncology

Cancer is a fatal disease and the second most cause of death worldwide. Treatment of cancer is a complex process and requires a multi-modality-based approach. Cancer detection and treatment starts with screening/diagnosis and continues till the patient is alive. Screening/diagnosis of the disease is the beginning of cancer management and continued with the staging of the disease, planning and delivery of treatment, treatment monitoring, and ongoing monitoring and follow-up. Imaging plays an important role in all stages of cancer management. Conventional oncology practice considers that all patients are similar in a disease type, whereas biomarkers subgroup the patients in a disease type which leads to the development of precision oncology. The utilization of the radiomic process has facilitated the advancement of diverse imaging biomarkers that find application in precision oncology. The role of imaging biomarkers and artificial intelligence (AI) in oncology has been investigated by many researchers in the past. The existing literature is suggestive of the increasing role of imaging biomarkers and AI in oncology. However, the stability of radiomic features has also been questioned. The radiomic community has recognized that the instability of radiomic features poses a danger to the global generalization of radiomic-based prediction models. In order to establish radiomic-based imaging biomarkers in oncology, the robustness of radiomic features needs to be established on a priority basis. This is because radiomic models developed in one institution frequently perform poorly in other institutions, most likely due to radiomic feature instability. To generalize radiomic-based prediction models in oncology, a number of initiatives, including Quantitative Imaging Network (QIN), Quantitative Imaging Biomarkers Alliance (QIBA), and Image Biomarker Standardisation Initiative (IBSI), have been launched to stabilize the radiomic features.

Clinical Concept-Based Radiology Reports Classification Pipeline for Lung Carcinoma

Rising incidence and mortality of cancer have led to an incremental amount of research in the field. To learn from preexisting data, it has become important to capture maximum information related to disease type, stage, treatment, and outcomes. Medical imaging reports are rich in this kind of information but are only present as free text. The extraction of information from such unstructured text reports is labor-intensive. The use of Natural Language Processing (NLP) tools to extract information from radiology reports can make it less time-consuming as well as more effective. In this study, we have developed and compared different models for the classification of lung carcinoma reports using clinical concepts. This study was approved by the institutional ethics committee as a retrospective study with a waiver of informed consent. A clinical concept-based classification pipeline for lung carcinoma radiology reports was developed using rule-based as well as machine learning models and compared. The machine learning models used were XGBoost and two more deep learning model architectures with bidirectional long short-term neural networks. A corpus consisting of 1700 radiology reports including computed tomography (CT) and positron emission tomography/computed tomography (PET/CT) reports were used for development and testing. Five hundred one radiology reports from MIMIC-III Clinical Database version 1.4 was used for external validation. The pipeline achieved an overall F1 score of 0.94 on the internal set and 0.74 on external validation with the rule-based algorithm using expert input giving the best performance. Among the machine learning models, the Bi-LSTM_dropout model performed better than the ML model using XGBoost and the Bi-LSTM_simple model on internal set, whereas on external validation, the Bi-LSTM_simple model performed relatively better than other 2. This pipeline can be used for clinical concept-based classification of radiology reports related to lung carcinoma from a huge corpus and also for automated annotation of these reports.

Machine-Learning-Based Radiomics for Classifying Glioma Grade from Magnetic Resonance Images of the Brain

Grading of gliomas is a piece of critical information related to prognosis and survival. Classifying glioma grade by semantic radiological features is subjective, requires multiple MRI sequences, is quite complex and clinically demanding, and can very often result in erroneous radiological diagnosis. We used a radiomics approach with machine learning classifiers to determine the grade of gliomas. Eighty-three patients with histopathologically proven gliomas underwent MRI of the brain. Whenever available, immunohistochemistry was additionally used to augment the histopathological diagnosis. Segmentation was performed manually on the T2W MR sequence using the TexRad texture analysis softwareTM, Version 3.10. Forty-two radiomics features, which included first-order features and shape features, were derived and compared between high-grade and low-grade gliomas. Features were selected by recursive feature elimination using a random forest algorithm method. The classification performance of the models was measured using accuracy, precision, recall, f1 score, and area under the curve (AUC) of the receiver operating characteristic curve. A 10-fold cross-validation was adopted to separate the training and the test data. The selected features were used to build five classifier models: support vector machine, random forest, gradient boost, naive Bayes, and AdaBoost classifiers. The random forest model performed the best, achieving an AUC of 0.81, an accuracy of 0.83, f1 score of 0.88, a recall of 0.93, and a precision of 0.85 for the test cohort. The results suggest that machine-learning-based radiomics features extracted from multiparametric MRI images can provide a non-invasive method for predicting glioma grades preoperatively. In the present study, we extracted the radiomics features from a single cross-sectional image of the T2W MRI sequence and utilized these features to build a fairly robust model to classify low-grade gliomas from high-grade gliomas (grade 4 gliomas).

Systematic review and meta-analysis of prediction models used in cervical cancer

BACKGROUND

Cervical cancer is one of the most common cancers in women with an incidence of around 6.5 % of all the cancer in women worldwide. Early detection and adequate treatment according to staging improve the patient's life expectancy. Outcome prediction models might aid treatment decisions, but a systematic review on prediction models for cervical cancer patients is not available.

DESIGN

We performed a systematic review for prediction models in cervical cancer following PRISMA guidelines. Key features that were used for model training and validation, the endpoints were extracted from the article and data were analyzed. Selected articles were grouped based on prediction endpoints i.e. Group1: Overall survival, Group2: progression-free survival; Group3: recurrence or distant metastasis; Group4: treatment response; Group5: toxicity or quality of life. We developed a scoring system to evaluate the manuscript. As per our criteria, studies were divided into four groups based on scores obtained in our scoring system, the Most significant study (Score > 60 %); Significant study (60 % > Score > 50 %); Moderately Significant study (50 % > Score > 40 %); least significant study (score < 40 %). A meta-analysis was performed for all the groups separately.

RESULTS

The first line of search selected 1358 articles and finally 39 articles were selected as eligible for inclusion in the review. As per our assessment criteria, 16, 13 and 10 studies were found to be the most significant, significant and moderately significant respectively. The intra-group pooled correlation coefficient for Group1, Group2, Group3, Group4, and Group5 were 0.76 [0.72, 0.79], 0.80 [0.73, 0.86], 0.87 [0.83, 0.90], 0.85 [0.77, 0.90], 0.88 [0.85, 0.90] respectively. All the models were found to be good (prediction accuracy [c-index/AUC/R²] >0.7) in endpoint prediction.

CONCLUSIONS

Prediction models of cervical cancer toxicity, local or distant recurrence and survival prediction show promising results with reasonable prediction accuracy [c-index/AUC/R² > 0.7]. These models should also be validated on external data and evaluated in prospective clinical studies.

Large Anorectal Venous Malformation Treated With Microfoam Therapy

Deficiency of smooth muscle cells can lead to dysfunction and engorgement of blood vessels termed as hemangioma, arteriovenous malformations, and venous malformations (VMs). Anorectal VM is a rare disease. It can present with massive hematochezia. An optimal treatment of anorectal VMs has not been defined. Surgery is an option if the lesion can be resected completely. Endoscopic injection sclerotherapy has been reported to be effective in treating small colorectal VMs. However, it has rarely been described in the treatment of large VMs. In this study, we describe a rare case of large anorectal VMs treated with microfoam sclerotherapy.

Analysis of image quality by regulating beta function of BSREM reconstruction algorithm and comparison with conventional reconstructions in carcinoma breast studies of PET CT with BGO detector

BACKGROUND

The study aimed to evaluate the beta penalization factor of the BSREM reconstruction algorithm on a five-ring BGO-based PET CT system and compared it with conventional reconstructions.

METHODS

Retrospective study involves 30 breast cancer patient data of 18F-fluorodeoxyglucose ( 18 F-FDG) PET CT for reconstruction with OSEM, OSEM + PSF, and BSREM under variable β factors ranging from 200 to 600 in the steps of 50. Liver noise, lesion SUVmax, SBR, and SNR for each reconstruction were calculated. Quantitative parameters of each beta factor of BSREM were compared with OSEM and OSEM + PSF, using the Wilcoxon sign rank test with Bonferroni correction, a value of P < 0.002 was considered statistically significant. Visual scoring by two readers was also evaluated.

RESULTS

Thirty lesions of mean size 1.91 ± 0.58 cm range (0.7-3.6 cm) were identified. Liver noise and SBR were reduced, whereas SNR was increased with an increasing β value of BSREM. In comparison with OSEM, liver noise was not significantly different from β200 and β250. SNR of OSEM was significantly lower than any other β factors and SBR of β factor less than 500 was significantly higher than OSEM. In comparison with OSEM + PSF, liver noise was not significantly different from β400 and β350-500 do not show a significant difference in SNR and SBR compared with OSEM + PSF. β350 scored highest under visual scoring with a moderate agreement.

CONCLUSION

The study quantitatively indicates the optimum beta range of β250-450 and the qualitative evaluation indicates that β350 is an optimum beta factor of BSREM in breast cancer cases for 18 F-FDG WB-PET CT.

Joint EANM/SNMMI guideline on radiomics in nuclear medicine : Jointly supported by the EANM Physics Committee and the SNMMI Physics, Instrumentation and Data Sciences Council

PURPOSE

The purpose of this guideline is to provide comprehensive information on best practices for robust radiomics analyses for both hand-crafted and deep learning-based approaches.

METHODS

In a cooperative effort between the EANM and SNMMI, we agreed upon current best practices and recommendations for relevant aspects of radiomics analyses, including study design, quality assurance, data collection, impact of acquisition and reconstruction, detection and segmentation, feature standardization and implementation, as well as appropriate modelling schemes, model evaluation, and interpretation. We also offer an outlook for future perspectives.

CONCLUSION

Radiomics is a very quickly evolving field of research. The present guideline focused on established findings as well as recommendations based on the state of the art. Though this guideline recognizes both hand-crafted and deep learning-based radiomics approaches, it primarily focuses on the former as this field is more mature. This guideline will be updated once more studies and results have contributed to improved consensus regarding the application of deep learning methods for radiomics. Although methodological recommendations in the present document are valid for most medical image modalities, we focus here on nuclear medicine, and specific recommendations when necessary are made for PET/CT, PET/MR, and quantitative SPECT.

Assessment of aeolian dust concentration, elemental composition, and their wet and dry deposition fluxes over the Northeast Arabian Sea

Atmospheric aerosol over the Arabian Sea is significantly impacted by the long-range transported mineral dust from the surrounding continents. This transported mineral dust is hypothesized and tested during several studies to see the impacts on the surface ocean biogeochemical processes and subsequently to the Carbon cycle. It is, thus important to quantify dust contributions and their fluxes to the Arabian Sea. Here we assess temporal variability of dust concentration, their elemental characteristics as well as quantify their dry and wet deposition fluxes over the North-eastern Arabian Sea. The dust concentrations were found to vary from 59 to 132 µg m^-3 which accounts for 50% to 90% of total mass during dusty days. However, its contribution during pre and post dust storms ranges between 6% and 60%. Relatively higher dust dry deposition flux of 28 ± 7 mg m^-2 day^-1 (range: 20-44) is estimated for dusty days compared to pre and post dusty days (range: 0.4-22 mg m^-2 day^-1). In contrast to dry deposition fluxes, significantly higher fluxes are estimated from wet deposition, averaging around 240 ± 220 mg m^-2 day^-1. These values are five times higher than those reported from cruise samples collected over the Arabian Sea. The contribution of dust to aerosol mass is further ascertained using elemental composition, wherein a significant correlation was observed between Fe and Al (r² = 0.77) for samples collected during the dusty period, highlighting their similar crustal sources. Our estimation of dust flux over this region has implications for the supply of nutrients associated with natural dust to the surface water of the Arabian Sea.Implications: The Arabian Sea, one of the productive oceanic regions among the global oceans, has been identified as a perennial source of atmospheric CO₂. This basin is heavily impacted by atmospheric dust deposition/inputs owing to its geographical location being surrounded by arid and semi-arid regions. It has been hypothesized that aeolian dust plays a significant role in modulating surface water biogeochemical processes including primary productivity, in the Arabian Sea. Furthermore, modelling studies have highlighted on the role of dust (containing Fe) in fueling and enhancing primary productivity in the Arabian Sea. However, quantification of dust deposition fluxes (wet and dry) on seasonal time scale is missing in the literature. This paper aims to partially fulfil this research gap by providing a long-term data of wet and dry deposition fluxes over the northeastern Arabian Sea. We have also discussed their seasonal variability and factors affecting this flux. Thus, this study will be valuable contribution to the aeolian research community and have significant implication toward the role of aeolian deposition to the surface water biogeochemical processes in the Arabian Sea.

Comparative Study of the Role of MRCP and USG in Patients with Pancreatic Duct and Biliary Duct Pathology

Background: Various imaging modalities like USG, CT, Invasive cholangiography has been used since long for the evaluation of the pathology of hepato-biliary-pancreatic duct. These techniques pose some limitations either due to bowel gas and obesity in USG, distal CBD calculus and isodense calculus (isodense to bile) in CT (also not used in patient with history of contrast allergy) and post-procedural complications (followed by invasive cholangiography like ERCP and PTC). MRCP is a non-invasive diagnostic technique for the direct visualization of the biliary ducts images similar to that produced in PTC (percutaneous trans-hepatic cholangiography) and ERCP. Also, the continuous expanding spectrum of therapeutic options, including radiological interventions (for palliative and curative) for the patients with biliary tree pathology requires the accurate assessment of the lesion visualized. Aims & objectives: Comparison of sensitivity, specificity and diagnostic accuracy between the MRCP/MRI and USG in patients with pancreatic and hepato-biliary pathology and it’s related complications. Materials & methods: The study was a retrospective, single institutional study done during the last two years (January 2018 – December 2019) at IGIMS, Patna, Bihar (A tertiary care hospital). Data was collected from the departmental record for USG findings, medical record for history and PACS (Picture archiving and communicating system) for MRCP findings. Hundred patients were included in our study. All the data were entered in the MS Excel sheet and were expressed as percentage and variables as required. Vassarstats software was used for the data analysis. Results: Benign lesions were common in the age range of 46-60 years (23%), followed by 31-45 years. Most of the malignant lesions were detected in the age range of 31-45 years of age group (13%). USG detected and MRCP detected lesions were benign in 63% and 62% of the cases and malignant in 34% and 35% of the cases respectively. There were overlapping findings present in most of the cases. Pancreatitis, cholecystitis and choledochal cysts were usually associated with biliary tree calculi. Overall sensitivity, specificity and diagnostic accuracy of MRI with MRCP sequence (97%, 85% and 92.75%) is greater than that of USG (92%, 80% and 85.5%). Conclusion: MRCP combined with other MRI sequences was superior to the USG in identifying benign and malignant pathology. However, ultrasound remains the primary investigating modality of choice. However, with use of recent advances of USG like harmonic imaging there is significant improvement in the lesion characterization. MRCP is the modality of choice of imaging investigation for the characterization of the lesion especially in obese patients or to choose the patients who are ideal candidate for the MRCP. Keywords: Hepato-biliary-pancreatic pathology, MRCP

Radiomics: a quantitative imaging biomarker in precision oncology

Cancer treatment is heading towards precision medicine driven by genetic and biochemical markers. Various genetic and biochemical markers are utilized to render personalized treatment in cancer. In the last decade, noninvasive imaging biomarkers have also been developed to assist personalized decision support systems in oncology. The imaging biomarkers i.e., radiomics is being researched to develop specific digital phenotype of tumor in cancer. Radiomics is a process to extract high throughput data from medical images by using advanced mathematical and statistical algorithms. The radiomics process involves various steps i.e., image generation, segmentation of region of interest (e.g. a tumor), image preprocessing, radiomic feature extraction, feature analysis and selection and finally prediction model development. Radiomics process explores the heterogeneity, irregularity and size parameters of the tumor to calculate thousands of advanced features. Our study investigates the role of radiomics in precision oncology. Radiomics research has witnessed a rapid growth in the last decade with several studies published that show the potential of radiomics in diagnosis and treatment outcome prediction in oncology. Several radiomics based prediction models have been developed and reported in the literature to predict various prediction endpoints i.e., overall survival, progression-free survival and recurrence in various cancer i.e., brain tumor, head and neck cancer, lung cancer and several other cancer types. Radiomics based digital phenotypes have shown promising results in diagnosis and treatment outcome prediction in oncology. In the coming years, radiomics is going to play a significant role in precision oncology.

Innovational duality and sustainable development: finding optima amidst socio-ecological policy trade-off in post-COVID-19 era

Purpose

This study aims to analyze the socio-ecological policy trade-off caused by technological innovations in the post-COVID-19 era. The study outcomes are utilized to design a comprehensive policy framework for attaining sustainable development goals (SDGs).

Design/methodology/approach

Study is done for 100 countries over 1991–2019. Second-generation estimation method is used. Innovation is measured by total factor productivity, environmental quality is measured by carbon dioxide (CO2) emissions and social dimension is captured by unemployment.

Findings

Innovation–CO2 emissions association is found to be inverted U-shaped and innovation–unemployment association is found to be U-shaped.

Research limitations/implications

The study outcomes show the conflicting impact of technological innovation leading to policy trade-off. This dual impact of innovation is considered during policy recommendation.

Practical implications

The policy framework recommended in the study shows a way to address the objectives of SDG 8, 9 and 13 during post-COVID-19 period.

Social implications

Policy recommendations in the study show a way to internalize the negative social externality exerted by innovation.

Originality/value

This study contributes to the literature by considering the policy trade-off caused by innovation and recommending an SDG-oriented policy framework for the post-COVID-19 era.

Synthesis, molecular docking, and biological evaluation of Schiff base hybrids of 1,2,4-triazole-pyridine as dihydrofolate reductase inhibitors

In this study novel derivatives of 1,2,4-triazole pyridine coupled with Schiff base were obtained in altered aromatic aldehyde and 4-((5-(pyridin-3-yl)-4H-1,2,4-triazol-3-ylthio)methyl)benzenamine reactions. Thin layer chromatography and melting point determination were employed to verify the purity of hybrid derivatives. The structures of the hybrid derivatives were interpreted using methods comprising infrared, nuclear magnetic resonance, and mass spectroscopy. The in vitro anti-microbial properties and minimum inhibitory concentration were determined with Gram-positive and Gram-negative bacteria. Among the derivatives produced, two derivatives comprising (Z)-2-((4-((5-(pyridine-3-yl)-4H-1,2,4-triazol-3-ylthio)methyl)phenylimino)methyl)phenoland (Z)-2-methoxy-5-((4-((5-(pyridine-3-yl)-4H-1,2,4-triazol-3- ylthio)methyl)phenylimino)methyl)phenol obtained promising results as antibacterial agents. After synthesizing different derivatives, docking studies were performed and the scores range from −10.3154 to −12.962 ​kcal/mol.

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Synthesis and evaluation of Schiff Base Hybrids of 1, 2, 4-Triazole-Pyridine as DHFR Inhibitors.

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Schiff Base Hybrids shown promising antibacterial results.

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Docking studies reveals a good binding affinity in range of -10.3154 to -12.962 kcal/mol with DHFR.

Installation and Optimization of 68Ga Synthesis Module for Clinical Use: An Institutional Experience

Introduction:

With advent of gallium-labeling somatostatin analogs and its evaluation under positron emission tomography–computed tomography, there has been a tremendous surge in its application. Gallium 68 can be made available either from onsite cyclotron production or in the form of ready-to-use ⁶⁸Ge/⁶⁸Ga generators. Wherein setting up and running of cyclotron amounts to huge investment and dedicated team, the ⁶⁸Ge/⁶⁸Ga generator has proved to be a better option and viable project. Moreover, due to long half-life of ⁶⁸Ge, i.e. 271 days, it enables the usage of generator for several months. The preparation of gallium-labeled peptides is much simpler in comparison to 18F radiochemistry, but the radiation exposure has always been an area of concern owing to high-energy annihilation photon of 511 keV.

Materials and Methods:

In this study, we share our experience of self-installation of ⁶⁸Ge/⁶⁸Ga generator during lockdown and the various steps involved in installation of fully automated peptide-labeling system in customized mini hot cell module, synthesis steps, and quality control steps of gallium-based radiopharmaceutical.

Results:

The installation was successfully completed with online assistance during the pandemic situation. The average elution yield met company specification (>80%), and ⁶⁸Ga-labeled peptides were prepared with high radiochemical purity (>95%). The overall exposure in single batch of production and quality control never exceeded 3 μSv as shielding was well-taken care of with customized mini hot cell.

Conclusion:

With the described experience and validation process, one can easily think of making an installation at his/her center and cater to the needs of society with a new radiopharmaceutical.

Normal Skeletal Standardized Uptake Values Obtained from Quantitative Single-Photon Emission Computed Tomography/Computed Tomography: Time-Dependent Study on Breast Cancer Patients

Aim:

To estimate the standard uptake values (SUVs) of Tc-99m methylene-diphosphonate (Tc-99m MDP) from normal skeletal sites in breast cancer patients using quantitative single-photon emission computed tomography (SPECT).

Materials and Methods:

A total of 60 breast cancer patients who underwent Tc-99m MDP SPECT/CT study at different postinjection acquisition times were included in this study. Based on postinjection acquisition time, patients were divided into four study groups (n_15 each), i.e. I^st (2 h), II^nd (3 h), III^rd (4 h), and IV^th (5 h). Image quantification (SUVmax and SUVmean) was performed using Q.Metrix software. Delineation of volume of interest was shaped around different bones of the skeletal system.

Results:

The highest normal SUVmax and SUVmean values were observed in lumber and thoracic vertebra (8.89 ± 2.26 and 2.89 ± 0.58) for Group I and in pelvis and thoracic (9.6 ± 1.32 and 3.04 ± 0.64), (10.93 ± 3.91 and 3.65 ± 0.97), (11.33 ± 2.67 and 3.65 ± 0.22) for Group II, III and IV, respectively. Lowest normal SUVmax and SUVmean values were observed in humerus and ribs (3.22 ± 0.67 and 0.97 ± 0.18), (5.16 ± 1.82 and 1.18 ± 0.16) for Group I, IV, and in humerus (3.17 ± 0.58 and 0.85 ± 0.26), (3.98 ± 1.12 and 1.04 ± 0.28) for Group II and III, respectively. Significant difference (P < 0.05) noted in SUVmax for sternum, cervical, humerus, ribs, and pelvis with respect to time. However, significant difference (P < 0.05) noted in SUVmean for all skeletal sites with respect to time.

Conclusions:

Our study shows variability in normal SUV values for different skeletal sites in breast cancer patients. Vertebral bodies and pelvis contribute highest SUV values. Time dependency of SUVs emphasizes the usefulness of routinely acquired images at the same time after Tc-99m MDP injection, especially in follow-up studies.

Torsion of spleen and portal hypertension: Pathophysiology and clinical implications

The displacement of spleen from its normal location to other places is known as wandering spleen (WS) and is a rare disease. The repeated torsion of WS is due to the presence of long pedicle and absence/laxity of anchoring ligaments. A WS is an extremely rare cause of left-sided portal hypertension (PHT) and severe gastric variceal bleeding. Left-sided PHT usually occurs as a result of splenic vein occlusion caused by splenic torsion, extrinsic compression of the splenic pedicle by enlarged spleen, and splenic vein thrombosis. There is a paucity of data on WS-related PHT, and these data are mostly in the form of case reports. In this review, we have analyzed the data of 20 reported cases of WS-related PHT. The mechanisms of pathogenesis, clinico-demographic profile, and clinical implications are described in this article. The majority of patients were diagnosed in the second to third decade of life (mean age: 26 years), with a strong female preponderance (M:F = 1:9). Eleven of the 20 WS patients with left-sided PHT presented with abdominal pain and mass. In 6 of the 11 patients, varices were detected incidentally on preoperative imaging studies or discovered intraoperatively. Therefore, pre-operative search for varices is required in patients with splenic torsion.

Importance of Understanding and Analyzing Daily Quality Assurance Test of Positron Emission Tomography/Computed Tomography Equipment in Minimizing the Downtime of Equipment in Remote Places

This article briefly describes the event of a defective detector block in a daily quality assurance scan/blank scan and insists on implementing guidelines to scan or not to scan in such a scenario. The nuclear medicine physicist should have a clear understanding of the blank scan graph, which shall help rectify the right cause of problem and give confidence to the physician in reporting the acquired study. A routine blank scan in positron emission tomography signifies various parameters of the crystal (coincidence count rate, single count rate, dead time, and coincidence time along with energy response) and in some respect is analogous to the daily uniformity flood image for gamma cameras, providing an overall assessment of detector response. We encountered a bad detector block in our routine quality assurance scan/blank scan and analyzed the root cause behind such an error which was finally restored to normalcy by replacing the defected part with a new one and an error-free blank scan was established. The analysis was carried out by performing various possible checks and discussing the issue with service engineer to help identify the defects much before service engineer actually arrived in our department. This allowed us to take the correct decision and enabled us to get the scanner repaired faster. Hence, a good understanding of the daily quality control test and proper analysis of the same may result in swift decision-making and faster repair of equipment leading to minimal disruption in the clinical workflow as well as avoidance of suboptimal scanning leading to the wrong diagnosis.

Emerging role of artificial intelligence in nuclear medicine

The role of artificial intelligence is increasing in all branches of medicine. The emerging role of artificial intelligence applications in nuclear medicine is going to improve the nuclear medicine clinical workflow in the coming years. Initial research outcomes are suggestive of increasing role of artificial intelligence in nuclear medicine workflow, particularly where selective automation tasks are of concern. Artificial intelligence-assisted planning, dosimetry and procedure execution appear to be areas for rapid and significant development. The role of artificial intelligence in more directly imaging-related tasks, such as dose optimization, image corrections and image reconstruction, have been particularly strong points of artificial intelligence research in nuclear medicine. Natural Language Processing (NLP)-based text processing task is another area of interest of artificial intelligence implementation in nuclear medicine.

Neurological manifestations of hepatitis E virus infection: An overview

Hepatitis E virus (HEV) is an important cause of repeated waterborne outbreaks of acute hepatitis. Recently, several extrahepatic manifestations (EHMs) have been described in patients with HEV infection. Of these, neurological disorders are the most common EHM associated with HEV. The involvement of both the peripheral nervous system and central nervous system can occur together or in isolation. Patients can present with normal liver function tests, which can often be misleading for physicians. There is a paucity of data on HEV-related neurological manifestations; and these data are mostly described as case reports and case series. In this review, we analyzed data of 163 reported cases of HEV-related neurological disorders. The mechanisms of pathogenesis, clinico-demographic profile, and outcomes of the HEV-related neurological disorders are described in this article. Nerve root and plexus disorder were found to be the most commonly reported disease, followed by meningoencephalitis.

Impact of High Temperature and Humidity on the Performance of Positron Emission Tomography Scanner

Positron emission tomography/computed tomography (PET/CT) scanner is a state-of-art imaging device. Susceptibility of PET scanner in fluctuation environmental condition is known. Hence, every vendor prescribes the optimal conditions such as temperature and humidity to maintain the equipment in its best condition. In a hot summer day, we faced an unexpected long duration power failure in our department after administration of F-18 fluorodeoxyglucose to one of our patients. As air condition was not working in our department, temperature in the machine room went far beyond the prescribed level. As we had already injected the patient, we decided to perform PET scan of that patient in the existing condition in the machine room. When we reviewed the scan, we identified significant count loss in the image, which raised doubt in our mind. We discussed with our colleague and decided to perform a daily quality assurance (DQA) test to assess the condition of the equipment in high temperature. On DQA scan, we spotted several changes in the uniformity plot as well as energy plot. Following to that, the system was shut down completely till the main supply was restored successfully, and room temperature and humidity was restored to normal in machine room and console room. After several hours of restoration of normal condition in console and machine room, PET/CT equipment was restarted, and the DQA was repeated. On review, we found the restoration of normal DQA graph. We conclude that the sudden increase in temperature and humidity in PET/CT equipment room affects the performance of scanner which reflects as count deficit in the image. This impairment in the image quality may be because of bismuth germanate crystal, photomultiplier tubes, and associated electronics.

Plastic versus metal stents for inoperable gallbladder cancer with hilar biliary obstruction: the jury is still out

In unresectable malignant hilar obstruction, adequate biliary drainage can be achieved with endoscopic placement of plastic or metal stents. Stent patency and patient survival may differ, depending on the primary disease, disease progression and stent type. Metal and plastic stents were compared in patients with malignant hilar strictures in several studies, but these studies mainly included patients who had cholangiocarcinoma, without taking into consideration potential differences in the invasion properties of tumor cells, histological differentiation and the biological behavior of different tumors. Gallbladder cancer (GBC) is the most common malignancy of the biliary tract, especially in the Indian subcontinent and Latin America. About half the patients with GBC present with jaundice, which usually means the tumor is inoperable. Palliative endoscopic stenting remains the first-line treatment of unresectable GBC with biliary obstruction. Primary disease progression is faster in GBC compared to cholangiocarcinoma. There is a paucity of data on the selection of stents for inoperable GBC with hilar biliary obstruction. This review focuses on the published literature related to the selection of stents for unresectable GBC with hilar obstruction.

Short-term mortality in patients with cirrhosis of the liver and acute kidney injury: A prospective observational study

INTRODUCTION

Renal failure is a common and severe complication of cirrhosis and confers poor prognosis. Serum creatinine is the most practical biomarker of renal function. Serum creatinine estimation in cirrhosis of the liver is affected by decreased formation, increased tubular secretion, increased volume of distribution, and interference by elevated bilirubin. Studies on the prognosis of cirrhotic patients using creatinine kinetics as a definition of acute kidney injury (AKI) proposed by the International Ascites Club are limited.

METHODS

In this single-center prospective observational study, decompensated cirrhotics with AKI defined by the International Ascites Club as the rise of serum creatinine ≥ 0.3 mg/dL within 48 h of admission or increase of serum creatinine ≥ 50% from stable baseline creatinine over the previous 3 months were followed and assessed for the development of complications during hospital course and in-hospital and 30-day mortality.

RESULTS

AKI developed in 142 out of 499 (28.45%) patients with cirrhosis. Twenty patients were excluded. The most common etiology of cirrhosis was alcohol (n = 64, 52%), and ascites was present in 115 (94%) patients. Eighty-two (67.21%) patients presented with AKI at the time of admission. Thirty-day mortality was 46.72% (57/122 patients). Hepatorenal syndrome had the highest mortality followed by AKI related to infection. Presence of jaundice and hepatic encephalopathy (HE) was associated with poor survival with adjusted hazard ratio of 3.54 and 2.17, respectively. On bivariate logistic regression analysis, jaundice, HE, type of AKI, AKI stage at maximum creatinine, bilirubin, serum glutamic oxaloacetic transaminase (SGOT), international normalized ratio (INR), and Child-Turcotte-Pugh (CTP) and model for end-stage liver disease (MELD) scores were predictors of mortality (p < 0.05). Sensitivity, specificity, and accuracy of MELD > 29 and CTP score > 11 were 75.44%, 82%, and 78.70% and 66.67%, 81.54%, and 74.60%, respectively for predicting 30-day mortality.

CONCLUSION

Development of AKI as defined by the International Ascites Club in cirrhosis confers high short-term mortality. Jaundice, HE, AKI stage, creatinine at enrollment, bilirubin, CTP, and MELD score were the predictors of mortality. Bullet points of the study highlights What is already known? • Renal failure is a common and severe complication of cirrhosis. • Serum creatinine is the most practical biomarker of renal function but it has many limitations in cirrhotic patients. • Creatinine kinetics-based definition of acute kidney injury (AKI) was proposed by the International Ascites Club. What is new in this study? • Short-term mortality (30 days) in decompensated cirrhotic patients with AKI as defined by the International Ascites Club using creatinine kinetics was high. • AKI due to hepatorenal syndrome (HRS) has the highest short-term (30 days) mortality followed by AKI due to infection in decompensated cirrhosis. • Detection of AKI using creatinine kinetics-based definition may prompt an early appropriate intervention. What are the future clinical and research implications of study findings? • Creatinine kinetics-based definition of AKI diagnose renal injury at an earlier stage; an appropriate intervention should be initiated at the earliest in these patients to improve patient survival.

Performance characteristic evaluation of a bismuth germanate-based high-sensitivity 5-ring discovery image quality positron emission tomography/computed tomography system as per National Electrical Manufacturers Association NU 2-2012

National Electrical Manufacturers Association (NEMA) provides guidelines to assess the performance of Positron Emission Tomography (PET). A PET/CT scanner, Discovery IQ, GE Medical systems, Milwaukee, USA was installed in our department which has high a sensitivity PET component. We have performed the NEMA NU-2 2012 quality control tests to evaluate this system on site before clinical use. Performance measurements of the PET scanner were made using the NEMA NU2-2012 procedures for spatial resolution, scatter fraction, sensitivity, count rate loss and random coincidence estimation, Noise Equivalent Count Rate (NECR) and image quality. As per NU2 2012, spatial resolution was measured at 1 cm, 10 cm and 20 cm vertically from the centre and at each of these points resolution was measured at tangential, radial and axial directions. Sensitivity was measured at centre and 10 cm off center vertically from the center. The system sensitivity is reported as an average of the two measured values. Scatter fraction and NECR measurements, Image quality test was also performed. The tangential, radial and axial FWHM were 4.99 mm, 4.20 mm and 4.79 mm at 1 cm off centre, 5.49 mm, 4.69 mm and 4.81 mm at 10 cm off centre and 7.99 mm, 5.07 mm and 4.95 mm at 20 cm off centre respectively. The absolute sensitivity of this scanner was found to be 20.1 cps/kBq. The scatter fraction calculated from the decay method was 37.94% and NECR was 125 kcps. The peak NECR was achieved at activity concentration of 8.7 KBq/ml and the count loss below the peak NECR was found to be 0.68%. Image quality test for, contrast recovery, background variability and lung error residual mean met all specifications. Overall PET performance of Discovery IQ whole-body scanner was satisfactory and the scanner met all the performance specifications required by NEMA 2012.

Transgastric migration of gossypiboma: A preventable complication

Gossypiboma is term given for retained piece of cotton/sponge during surgery. The incidence of gossypiboma has described as 1 in 1000-3000 surgeries. Incidence is underestimated because of underreporting due to fear of medico-legal litigation and extreme criticism by media. Intraluminal migration is a rare complication of gossypiboma. Small intestine is most common intraluminal site followed by duodenum. Here, we report sixth case of transgastric migration of gossypiboma.

Nanotechnology in gastrointestinal endoscopy: A primer

Nanotechnology is the understanding, control of matter and development of engineered devices in nanometer range (1-100 nm). Nanoparticles have different physicochemical properties (small size, large surface area to volume ratio, and high reactivity) in comparison to bulk materials of the same composition. The nanotechnology has proved its usefulness in early diagnosis, proteonomics, imaging diagnostics and multifunctional therapeutics. Recent studies have shown its role in early diagnosis and targeted therapy of various gastrointestinal disorders such as hepatitis B virus and hepatitis C virus related liver disease, inflammatory bowel disease, gastric ulcer, and malignancy. Application of this technology appears promising in diagnostic and therapeutic endoscopy such as the endoscopic hemostasis of peptic ulcer bleeding, prevention of clogging of plastic stent and advance capsule endoscopy. This article will highlight the basic concepts of nanotechnology and its potential application in gastrointestinal endoscopy.

Delayed mesh erosion after rectopexy: A rare surprise diagnosis

Mesh rectopexy is a frequently performed surgery for the treatment of rectal prolapse. Mesh rectopexy may be complicated by mesh infection, mesh erosion/migration into bowel wall, and extrusion of mesh. Erosion of the mesh into the rectum is very rare. Delayed erosion of mesh into rectosigmoid can present after many years of mesh rectopexy and poses diagnostic dilemma. We report a case of delayed mesh erosion into the rectum diagnosed during sigmoidoscopy.

Towards continuous-to-continuous 3D imaging in the real world

Imaging systems are often modeled as continuous-to-discrete mappings that map the object (i.e. a function of continuous variables such as space, time, energy, wavelength, etc) to a finite set of measurements. When it comes to reconstruction, some discretized version of the object is almost always assumed, leading to a discrete-to-discrete representation of the imaging system. In this paper, we discuss a method for single-photon emission computed tomography (SPECT) imaging that avoids discrete representations of the object or the imaging system, thus allowing reconstruction on an arbitrarily fine set of points.

Thyroid Bethesda Atypia of Undetermined Significance or Follicular Lesion of Undetermined Significance (AUS/FLUS): A Heterogenous Group

Background:

The Bethesda system of reporting thyroid cytopathology (BSRTC) was introduced in 2007. The third category of atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) poses difficulties for the pathologist, and different papers have been published varying the risks of malignancy.

Aims:

(1) Evaluation of the cytological features of thyroid lesions according to BSRTC. (2) After resection, correlation with histopathological report to evaluate the risk of malignancy (ROM) and the risk of neoplasm (RON). (3) Division of category III into six subgroups based on cytological findings and assessment of ROM and RON.

Materials and Methods:

A total of 282 patients with diagnosed thyroid lesions underwent fine-needle sampling under ultrasound guidance. Smears were prepared and stained with May–Grunwald–Giemsa stain and Papanicolaou stain.

Results:

Of 282 cases, there were 9 cases (3.1%) of category I, 157 cases (55.8%) of category II, 24 cases (8.5%) of category III, 20 cases (7.1%) of category IV, 14 cases (4.8%) of category V, and 58 cases (20.7%) of category VI. The RON was 60, 17.1, 63.1, 77.7, 91.7, and 98.2% and the ROM was 60, 14.3, 26.3, 38.9, 91.7, and 96.3% in categories I, II, III, IV, V, and VI, respectively. The RON was 0, 75, 50, 100, 66.6, and 100% and the ROM was 0, 25, 50, 100, 16.6, and 0% in subgroups 1, 2, 3, 4, 5, and 6, respectively. We have proposed a system of subgrouping AUS/FLUS that may help to dispel the confusion generated by an AUS/FLUS report, and provide with a more exact and reproducible diagnostic and prognostic tool.

The relation of toddy (palm wine) intake to amoebic liver abscess in a predominantly toddy-drinking population: a cross-sectional study

The role of toddy (palm wine) as an independent risk factor for amoebic liver abscess (ALA) is not clear. In a cross-sectional study, the clinico-demographic profiles of inpatients with ALA were examined. Microscopy examination of toddy (n = 43) samples was performed. A total of 198 patients with ALA were enrolled, most of whom were: admitted during the May-August months (48%); chronic alcoholic (85% [70% toddy]); malnourished (85%); and of low socioeconomic status (88%). Clinical and laboratory parameters were comparable between toddy and distilled alcohol drinkers. None of the toddy samples revealed presence of cysts and trophozoites of Entamoeba histolytica.

Spectrum of gastrointestinal involvement in Stevens - Johnson syndrome

Stevens - Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN) is a severe adverse drug reaction associated with involvement of skin and mucosal membranes, and carries significant risk of mortality and morbidity. Mucus membrane lesions usually involve the oral cavity, lips, bulbar conjunctiva and the anogenitalia. The oral/anal mucosa and liver are commonly involved in SJS or TEN. However, intestinal involvement is distinctly rare. We herein review the current literature regarding the gastrointestinal involvement in SJS or TEN. This review focuses mainly on the small bowel and colonic involvement in patients with SJS or TEN.

Performance of lemongrass (Cymbopogon citrates) oil as growth promoter in broiler

An attempt was taken to study the growth performance of lemongrass oil (Cymbopogon citraturs) as a growth promoter on the broiler production. A total of 180day-old broiler chicks were procured from private hatchery (Shivam Hatchery Birgung, Parsa, Nepal) and were allocated following Completely Randomized Design (CRD) into four treatment groups (each treatment with 3 replications and each replication with 15 birds); T1= control, T2= containing lemongrass oil 200 ml/100 kg feed, T3= containing lemongrass oil 400 ml/100 kg feed and, T4= containing lemongrass oil 600 ml/100 kg feed. The study was carried out for 36 days at Avian Research Unit, Regional Agriculture Research Station, Parwanipur, Bara, Nepal. Concentrate mixture and lemongrass oil were procured from Shakti Feed Industry, Birgung; Herbs Processing Plant of Ministry of Forest and Soil Conservation, Jadibuti, Kathmandu, respectively. Experimental birds were provided ad libitum amount of starter feed from 0 to 21 days and finisher feed from 22 to 36 days. Feed intake was recorded daily and body weight gain was measured in 7 days interval. The study revealed that the cumulative feed intake per bird was found higher in T3 (3443.17g) followed by T4 (3377.33g) and T2 (3354.04g), respectively, and were statistically non-significant among the diet groups. The FCR was highest in T3 (1:1.44 kg) and lowest in T4 (1:1.51 kg), and differed insignificantly among the diet groups. Similarly, the total weight gain of the experimental bird was found to be higher in T3 (2385.13g) followed by T1 (2279.46g) and T2 (2271.86g), respectively.  The average daily gain of experimental birds noted higher in T3 (66.25g) followed by T1 and T2 (63.31g) and (63.1g), respectively. The experiment suggested that inclusion of lemongrass oil could be considered as an alternative to antibiotic growth promoter in broiler diet to enhance the production performance. Bang. J. Anim. Sci. 2018. 47 (2): 85-91

Post-endoscopic retrograde cholangiopancreatography pneumothorax: Report of two cases and literature review

Pneumothorax is a very rare complication of endoscopic retrograde cholangiopancreatography. Here, we report two cases of pneumothorax following ERCP and sphincterotomy for choledocholithiasis. Patient was treated successfully with laprotomy and repair of a rent in the posterolateral wall of the second portion of duodenum. We also review the literature.

Complicated Cases of Lithium Battery Ingestion: Delay can be Deadly

Increasing use of button battery (BB) in household products and toys is responsible for the growing incidence of button battery ingestion (BBI). The BBI may cause life‑threatening complications. We present a series of three cases of complicated BBI (lithium cell) with delayed presentation; one of them could not survive due to tracheoesophageal fistula and sepsis. Here, we highlight the importance of early endoscopic intervention and careful follow‑up in children with lithium battery ingestion.

Optimal cut-off value of fecal calprotectin for the evaluation of ulcerative colitis: An unsolved issue?

Introduction

There is variability in the fecal calprotectin (FCP) cut‐off level for the prediction of ulcerative colitis (UC) disease activity and differentiation from irritable bowel disease (IBS‐D). The FCP cut‐off levels vary from country to country.

Aims

We aimed to assess FCP as a marker of disease activity in patients with UC. We determined the optimal FCP cut‐off value for differentiating UC and IBS‐D.

Methods

In a prospective study, we enrolled 76 UC and 30 IBS‐D patients. We studied the correlation of FCP with disease activity/extent as well as its role in differentiating UC from IBS‐D. We also reviewed literature regarding the optimal FCP cut‐off level for the prediction of disease activity and differentiation from IBS‐D patients.

Results

Sensitivity, specificity, positive predictive value, and negative predictive value of FCP (cut‐off level, 158 μg/g) for the prediction of complete mucosal healing (using Mayo endoscopic subscore) were 90, 85, 94.7, and 73.3%, respectively. Sensitivity, specificity, positive predictive value, and negative predictive value of FCP (cut‐off level, 425 μg/g) for the prediction of inactive disease (Mayo Score ≤ 2) were 94.3, 88.7, 86.2, and 95.4%, respectively. We also found a FCP cut‐off value of 188 μg/g for the differentiation of UC from IBS‐D.

Conclusions

The study reveals the large quantitative differences in FCP cut‐off levels in different study populations. This study demonstrates a wide variation in FCP cut‐off levels in the initial diagnosis of UC as well as in follow‐up post‐treatment. Therefore, this test requires validation of the available test kits and finding of appropriate cut‐off levels for different study populations.

Polyethylene glycol plus bisacodyl: A safe, cheap, and effective regimen for colonoscopy in the South Asian patients

Background and Aim

Data regarding the comparison of colonoscopic preparation regimens are still variable. We aimed to assess the adequacy and tolerability of two bowel preparation regimens for afternoon colonoscopy.

Methods

In a randomized, investigator‐blinded trial, two preparation regimens [4‐L split‐dose polyethylene glycol‐electrolytes (PEG‐ELS) and 2‐L PEG‐ELS plus bisacodyl) were compared in terms of bowel cleansing efficacy and adverse effects.

Results

The mean (±SD) age (years) of the 4‐L split‐dose PEG‐ELS group (N = 147) and the 2‐L PEG‐ELS plus bisacodyl (N = 155) were 44.09 (±15.62) (M:F : 2:1) and 44.12 years (±15.61) (M:F : 1.7:1), respectively. Percentage of patients with excellent and good preparation was higher in the 4‐L split‐dose PEG‐ELS regimen compared with the 2‐L PEG‐ELS plus bisacodyl regimen (22.44 vs 17.41 and 44.21% vs 36.12%). Percentage of patients with fair and poor preparation was lower in 4‐L split‐dose PEG‐ELS regimen compared with the 2‐L PEG‐ELS plus bisacodyl regimen (21.08% vs 27.74% and 12.24% vs 18.70%). In comparison with the 2‐L PEG‐ELS plus bisacodyl group, the incidences of abdominal pain (11% vs 15%), bloating (9% vs 12.24%), nausea/vomiting (8.38% vs 9.52%), and sleep disturbance (11% vs 12%) were slightly more common in the 4‐L split‐dose PEG‐ELS group. There were no statistically significant differences between the two regimens with regard to bowel cleansing efficacy and adverse events.

Conclusions

The 2‐L PEG‐ELS plus bisacodyl (10 mg) preparation is as efficacious as the 4‐L split‐dose PEG‐ELS regimen for afternoon colonoscopy. Optimal preparation for colonoscopy can be achieved with the 2‐L PEG‐ELS plus bisacodyl regimen with slightly fewer adverse events and lower cost compared to the 4‐L split‐dose PEG‐ELS regimen.

Masson's Hemangioma of the Cheek: A Case Report

We report a rare case of intravascular papillary endothelial hyperplasia (IPEH) of the cheek. This neoplasm, known as Masson's tumor, is an unusual vascular lesion of proliferating endothelial cells. It is usually confined to the lumen of preexisting vessels or vascular malformations. The principal significance of IPEH is its resemblance to a variety of benign and malignant diseases and possible misdiagnosis as such. Achieving a correct diagnosis is essential to avoid subjecting a patient to either unnecessarily aggressive or inadequate therapy. For this reason, awareness of this lesion is very important.

Giant Gastroduodenal Trichobezoar: An Endoscopic Surprise

A trichobezoar is a rare condition, mostly seen in teenage girls with abnormal psychiatric behavior of eating hairs and nails (trichophagia). Trichobezoar may rarely present with nonspecific abdominal symptoms without obvious trichotillomania and trichophagia. Trichobezoar can be complicated with potentially serious conditions such as gastric outlet obstruction, gastric bleeding, intussusceptions, and perforation peritonitis. Conventional laparotomy is method of choice for the removal of trichobezoar. We describe a rare case of giant trichobezoar treated by laparoscopic‑assisted gastrostomy and removal of bezoar. We also reviewed the literature on the current status of endoscopic treatment of trichobezoar.