Magnetic Resonance Urography in Obstructive Uropathy

Background

Urinary obstruction is one of the few reversible causes of renal failure. Early diagnosis and treatment can salvage the kidney. Presently intravenous urography, ultrasonography, computed tomography and magnetic resonance imaging are in vogue to detect the cause and demonstrate the site of obstruction.

Methods

An evaluation of imaging technique in obstructive uropathy was undertaken in a group of 25 patients.

Result and Conclusion

Magnetic resonance urography delivered highest accuracy amongst the techniques studied.Key Words: Magnetic resonance urography     

Three Dimensional Spiral CT Imaging of the Musculoskeletal System: Application and Advantages

Background

Clinical applications of spiral computed tomography (CT) have increased extensively over the past decade and continue to widen rapidly. The introduction of three-dimensional(3-D) reconstruction in CT technology has revolutionized medical imaging. This advancement has been possible due to the combination of spiral computed tomography and various 3-D reconstruction protocols which have permitted rapid and comprehensive examination of all regions of the body. It has unequivocal advantages in the preoperative planning of craniofacial surgery, assessment of complex fractures of the skeletal system especially pelvis and in the surgical treatment of dysplastic hips in children.

Methods

3-D spiral CT imaging of various parts of the musculoskeletal system was carried out in 60 cases using available protocols, at the CT scan center of a large tertiary care service hospital.

Results

The study provided a new approach in the analysis of complex anatomic relationships of the musculoskeletal system. Therapeutic planning whether surgical or medical was to a great extent aided by the anatomic information available from these images.

Conclusion

3-D CT imaging is a rapid, non-invasive and accurate technique for diagnosis, pre-operative evaluation as well as post-operative assessment of a large number of musculoskeletal diseases. 3-D CT studies have come to stay and with continued improvement in CT technology it has now become an integral part of imaging studies of the musculoskeletal system.Key Words: Spiral CT, 3-dimensional imaging, Musculoskeletal system     

Computed Tomographic Findings in 50 Cases of Gall Bladder Carcinoma

Background

A retrospective assessment of contrast enhanced computed tomography (CECT) scan findings in histopathologically proven cases of carcinoma of the gallbladder (GB) was performed to review its role in diagnosis, staging and assessment of surgical resectability.

Methods

All the patients had been subjected to a standardised abdominal helical computed tomography scan. Orally administered iodinated contrast was used for opacification of bowel and dynamic intravenous injection of non-ionic iodinated contrast for studying the lesional enhancement and vascular structures.

Results

The presence of focal or diffuse mass lesions in the gallbladder fossa, infiltration of a liver and second part of duodenum were the most reliable diagnostic features in carcinoma gallbladder. Regional spread was better delineated on CT scan as compared with ultrasonography.

Conclusion

CT scan is an effective method for evaluating, characterizing and detecting the spread of GB carcinomas.Key Words: Gall Bladder, Carcinoma, Computed Tomography     

Review: Pathology imaging informatics for quantitative analysis of whole-slide images

Objectives

With the objective of bringing clinical decision support systems to reality, this article reviews histopathological whole-slide imaging informatics methods, associated challenges, and future research opportunities.

Target audience

This review targets pathologists and informaticians who have a limited understanding of the key aspects of whole-slide image (WSI) analysis and/or a limited knowledge of state-of-the-art technologies and analysis methods.

Scope

First, we discuss the importance of imaging informatics in pathology and highlight the challenges posed by histopathological WSI. Next, we provide a thorough review of current methods for: quality control of histopathological images; feature extraction that captures image properties at the pixel, object, and semantic levels; predictive modeling that utilizes image features for diagnostic or prognostic applications; and data and information visualization that explores WSI for de novo discovery. In addition, we highlight future research directions and discuss the impact of large public repositories of histopathological data, such as the Cancer Genome Atlas, on the field of pathology informatics. Following the review, we present a case study to illustrate a clinical decision support system that begins with quality control and ends with predictive modeling for several cancer endpoints. Currently, state-of-the-art software tools only provide limited image processing capabilities instead of complete data analysis for clinical decision-making. We aim to inspire researchers to conduct more research in pathology imaging informatics so that clinical decision support can become a reality.     

Research and applications: MilxXplore: a web-based system to explore large imaging datasets

Objective

As large-scale medical imaging studies are becoming more common, there is an increasing reliance on automated software to extract quantitative information from these images. As the size of the cohorts keeps increasing with large studies, there is a also a need for tools that allow results from automated image processing and analysis to be presented in a way that enables fast and efficient quality checking, tagging and reporting on cases in which automatic processing failed or was problematic.

Materials and methods

MilxXplore is an open source visualization platform, which provides an interface to navigate and explore imaging data in a web browser, giving the end user the opportunity to perform quality control and reporting in a user friendly, collaborative and efficient way.

Discussion

Compared to existing software solutions that often provide an overview of the results at the subject''s level, MilxXplore pools the results of individual subjects and time points together, allowing easy and efficient navigation and browsing through the different acquisitions of a subject over time, and comparing the results against the rest of the population.

Conclusions

MilxXplore is fast, flexible and allows remote quality checks of processed imaging data, facilitating data sharing and collaboration across multiple locations, and can be easily integrated into a cloud computing pipeline. With the growing trend of open data and open science, such a tool will become increasingly important to share and publish results of imaging analysis.     

Research and applications: Imaging informatics for consumer health: towards a radiology patient portal

Objective

With the increased routine use of advanced imaging in clinical diagnosis and treatment, it has become imperative to provide patients with a means to view and understand their imaging studies. We illustrate the feasibility of a patient portal that automatically structures and integrates radiology reports with corresponding imaging studies according to several information orientations tailored for the layperson.

Methods

The imaging patient portal is composed of an image processing module for the creation of a timeline that illustrates the progression of disease, a natural language processing module to extract salient concepts from radiology reports (73% accuracy, F₁ score of 0.67), and an interactive user interface navigable by an imaging findings list. The portal was developed as a Java-based web application and is demonstrated for patients with brain cancer.

Results and discussion

The system was exhibited at an international radiology conference to solicit feedback from a diverse group of healthcare professionals. There was wide support for educating patients about their imaging studies, and an appreciation for the informatics tools used to simplify images and reports for consumer interpretation. Primary concerns included the possibility of patients misunderstanding their results, as well as worries regarding accidental improper disclosure of medical information.

Conclusions

Radiologic imaging composes a significant amount of the evidence used to make diagnostic and treatment decisions, yet there are few tools for explaining this information to patients. The proposed radiology patient portal provides a framework for organizing radiologic results into several information orientations to support patient education.     

Diffusion weighted magnetic resonance imaging for acute stroke: practical and popular

Aim

To evaluate the feasibility and impact of diffusion weighted magnetic resonance imaging (DW MRI) as the first line neuroimaging of stroke at a district general hospital.

Methods

Prospective audit of all in‐patients admitted with clinically suspected acute stroke and referred for imaging over a consecutive 17 week period. The data collected included scan type, time from cerebral event to imaging request, and time from formal radiological request to neuroimaging. Clinicians'' (general physicians, neurologists, and radiologists) perceptions were assessed by a questionnaire.

Results

148 patients had neuroimaging for clinically suspected stroke during this period. Eighty one per cent of patients (120 of 148) had DW MRI as first line. Ninety two per cent of these patients had DW MRI within 24 hours of the formal radiological request. Twenty eight patients did not undergo DW MRI because lack of MRI safety, clinical state, unavailability because of maintenance service or lack of trained staff. Clinicians found the introduction of the DW MRI based service a significant improvement on computed tomography, especially for equivocal cases.

Conclusion

DW based MRI service is both feasible and sustainable in the setting of a district general hospital and most clinicians feel that this is a significant improvement to stroke services.     

Patient-controlled sharing of medical imaging data across unaffiliated healthcare organizations

Background

Current image sharing is carried out by manual transportation of CDs by patients or organization-coordinated sharing networks. The former places a significant burden on patients and providers. The latter faces challenges to patient privacy.

Objective

To allow healthcare providers efficient access to medical imaging data acquired at other unaffiliated healthcare facilities while ensuring strong protection of patient privacy and minimizing burden on patients, providers, and the information technology infrastructure.

Methods

An image sharing framework is described that involves patients as an integral part of, and with full control of, the image sharing process. Central to this framework is the Patient Controlled Access-key REgistry (PCARE) which manages the access keys issued by image source facilities. When digitally signed by patients, the access keys are used by any requesting facility to retrieve the associated imaging data from the source facility. A centralized patient portal, called a PCARE patient control portal, allows patients to manage all the access keys in PCARE.

Results

A prototype of the PCARE framework has been developed by extending open-source technology. The results for feasibility, performance, and user assessments are encouraging and demonstrate the benefits of patient-controlled image sharing.

Discussion

The PCARE framework is effective in many important clinical cases of image sharing and can be used to integrate organization-coordinated sharing networks. The same framework can also be used to realize a longitudinal virtual electronic health record.

Conclusion

The PCARE framework allows prior imaging data to be shared among unaffiliated healthcare facilities while protecting patient privacy with minimal burden on patients, providers, and infrastructure. A prototype has been implemented to demonstrate the feasibility and benefits of this approach.     

Research and applications: Automatic glaucoma diagnosis through medical imaging informatics

Background

Computer-aided diagnosis for screening utilizes computer-based analytical methodologies to process patient information. Glaucoma is the leading irreversible cause of blindness. Due to the lack of an effective and standard screening practice, more than 50% of the cases are undiagnosed, which prevents the early treatment of the disease.

Objective

To design an automatic glaucoma diagnosis architecture automatic glaucoma diagnosis through medical imaging informatics (AGLAIA-MII) that combines patient personal data, medical retinal fundus image, and patient''s genome information for screening.

Materials and methods

2258 cases from a population study were used to evaluate the screening software. These cases were attributed with patient personal data, retinal images and quality controlled genome data. Utilizing the multiple kernel learning-based classifier, AGLAIA-MII, combined patient personal data, major image features, and important genome single nucleotide polymorphism (SNP) features.

Results and discussion

Receiver operating characteristic curves were plotted to compare AGLAIA-MII''s performance with classifiers using patient personal data, images, and genome SNP separately. AGLAIA-MII was able to achieve an area under curve value of 0.866, better than 0.551, 0.722 and 0.810 by the individual personal data, image and genome information components, respectively. AGLAIA-MII also demonstrated a substantial improvement over the current glaucoma screening approach based on intraocular pressure.

Conclusions

AGLAIA-MII demonstrates for the first time the capability of integrating patients’ personal data, medical retinal image and genome information for automatic glaucoma diagnosis and screening in a large dataset from a population study. It paves the way for a holistic approach for automatic objective glaucoma diagnosis and screening.     

Natural history,clinical pattern,and surgical considerations of pneumatosis intestinalis

Objective

Pneumatosis intestinalis has been increasingly detected in recent years with the more frequent use of computed tomography for abdominal imaging of the intestine. The underlying causes of the gas found during radiographic studies of the bowel wall can vary widely and different hypotheses regarding its pathophysiology have been postulated. Pneumatosis intestinalis often represents a benign condition and should not be considered an argument for surgery. However, it can also require life-threatening surgery in some cases, and this can be a difficult decision in some patients.

Methods

The spectrum of pneumatosis intestinalis is discussed here based on various computed tomographic and surgical findings in patients who presented at our University Medical Centre in 2003-2008. We have also systematically reviewed the literature to establish the current understanding of its aetiology and pathophysiology, and the possible clinical conditions associated with pneumatosis intestinalis and their management.

Results

Pneumatosis intestinalis is a primary radiographic finding. After its diagnosis, its specific pathogenesis should be ascertained because the appropriate therapy is related to the underlying cause of pneumatosis intestinalis, and this is sometimes difficult to define. Surgical treatment should be considered urgent in symptomatic patients presenting with an acute abdomen, signs of ischemia, or bowel obstruction. In asymptomatic patients with otherwise inconspicuous findings, the underlying disease should be treated first, rather than urgent exploratory surgery considered. Extensive and comprehensive information on the pathophysiology and clinical findings of pneumatosis intestinalis is provided here and is incorporated into a treatment algorithm.

Conclusions

The information presented here allows a better understanding of the radiographic diagnosis and underlying aetiology of pneumatosis intestinalis, and may facilitate the decision-making process in this context, thus providing fast and adequate therapy to particular patients.     

Lumbar radiculopathy caused by foraminal stenosis in rheumatoid arthritis

Study design

Case-series study.

Objective

To describe the clinical presentation, characteristic findings of imaging studies, and treatment of lumbar radiculopathy caused by foraminal stenosis in rheumatoid arthritis.

Background

Lumbar lesions in rheumatoid arthritis are relatively rare, with a limited number of systemic reports.

Methods

Six patients with lumbar radiculopathy caused by foraminal stenosis in rheumatoid arthritis were treated. The patients were all women with a mean age of 69 years and mean rheumatoid arthritis duration of 15 years. The medical records and imaging studies of all patients were reviewed.

Results

The affected nerve roots were L4 in four patients and L3 in two patients. Foraminal stenosis was not demonstrated in magnetic resonance images in four of the six patients. Selective radiculography with nerve root block reproduced pain, manifested blocking effect, and demonstrated compression of the nerve root by the superior articular process of the lower vertebra in all patients. Conservative treatment was performed on one patient, and surgery was conducted for the rest of the five patients; radiculopathy was improved in all patients.

Conclusions

Lumbar foraminal stenosis is a characteristic pathology of rheumatoid arthritis, and should be kept in mind in the diagnosis of lumbar radiculopathy. Selective radiculography is useful in the diagnosis of affected nerve roots.     

Visualisation of the Bonebridge by means of CT and CBCT

Background

With the Bonebridge, a new bone-anchored hearing aid has been available since March 2012. The objective of the study was to analyse the visualisation of the implant itself as well as its impact on the representation of the bony structures of the petrosal bone in CT, MRI and cone beam CT (CBCT).

Methods

The Bonebridge was implanted unilaterally in two completely prepared human heads. The radiological imaging by means of CBCT, 64-slice CT, 1.5-T and 3.0-T MRI was conducted both preoperatively and postoperatively. The images were subsequently evaluated from both the ENT medical and nd radiological perspectives.

Results

As anticipated, no visualisation of the implant or of the petrosal bones could be realised on MRI because of the interactive technology and the magnet artefact. In contrast, an excellent evaluability of the implant itself as well as of the surrounding neurovascular structures (sinus sigmoideus, skull base, middle ear, inner ear, inner auditory canal) was exhibited in both the CT and in the CBCT.

Conclusion

The Bonebridge can be excellently imaged with the radiological imaging technologies of CT and CBCT. In the process, CBCT shows discrete advantages in comparison with CT. No relevant restrictions in image quality in the evaluation of the bony structures of the petrosal bones could be seen.     

Research and applications: Supervised machine learning and active learning in classification of radiology reports

Objective

This paper presents an automated system for classifying the results of imaging examinations (CT, MRI, positron emission tomography) into reportable and non-reportable cancer cases. This system is part of an industrial-strength processing pipeline built to extract content from radiology reports for use in the Victorian Cancer Registry.

Materials and methods

In addition to traditional supervised learning methods such as conditional random fields and support vector machines, active learning (AL) approaches were investigated to optimize training production and further improve classification performance. The project involved two pilot sites in Victoria, Australia (Lake Imaging (Ballarat) and Peter MacCallum Cancer Centre (Melbourne)) and, in collaboration with the NSW Central Registry, one pilot site at Westmead Hospital (Sydney).

Results

The reportability classifier performance achieved 98.25% sensitivity and 96.14% specificity on the cancer registry''s held-out test set. Up to 92% of training data needed for supervised machine learning can be saved by AL.

Discussion

AL is a promising method for optimizing the supervised training production used in classification of radiology reports. When an AL strategy is applied during the data selection process, the cost of manual classification can be reduced significantly.

Conclusions

The most important practical application of the reportability classifier is that it can dramatically reduce human effort in identifying relevant reports from the large imaging pool for further investigation of cancer. The classifier is built on a large real-world dataset and can achieve high performance in filtering relevant reports to support cancer registries.     

Comparison of guideline recommendations with daily practice in patients with renal cell carcinoma

Objectives and Aims

To compare guideline recommendations with daily practice patterns in a German patient cohort with renal cell carcinoma.

Patients and methods

81 patients with T1 oder T2 renal cell carcinoma (RCC) were included in this prospective single-center study. All patients were operated in a single institution either by open radical nephrectomy (ORN) or nephron sparing surgery (NSS). Patients and doctors were evaluated using a written questionnaire with a follow-up of 12 months. Follow-up intervals, follow-up modalities (e. g. imaging modalities, laboratory controls of blood and urine) and the call on psycho-oncological support were evaluated.

Results

The majority of patients (72%) were followed up by their urologists. Follow-up examinations included abdominal ultrasound, urine and blood diagnostics, conventional chest x-rays, computed tomography (CT) of abdomen, chest or head or abdominal Magnetic Resonance Imaging (MRI). There were no significant differences between patients operated by ORN or NSS. In total, 12.5% of patients were asking for psycho-oncological support.

Conclusions

In general, patients were followed up according to existing guideline recommendations. Only a small proportion of patients asked for psycho-oncological treatment.     

Squamous odontogenic tumor of the mandible: a case report demonstrating immunoexpression of Notch1, 3, 4, Jagged1 and delta1

Background

Squamous odontogenic tumor (SOT) is a rare benign odontogenic epithelial neoplasm. A slow-growing painless expansive swelling is the common presenting symptom. Histopathologically, SOT can be easily misdiagnosed as an acanthomatous ameloblastoma. Although Notch receptors and ligands have been shown to play a role in cell fate decisions in ameloblastomas, the role of these cell signaling molecules in SOT is unknown.

Case report

This paper describes a case of SOT affecting the anterior mandible of a 10-year-old Indian female. The patient was treated by local surgical excision and there has been no follow-up clinical record of recurrence 5 years after primary treatment. Histopathological examination revealed a solid, locally-infiltrative neoplasm composed of bland-looking squamatoid islands scattered in a mature fibrous connective tissue stroma and the diagnosis was SOT. Immunohistochemical evaluation showed positive reactivity of varying intensity in the neoplastic epithelial cells for Notch1, Notch3, Notch4, and their ligands Jagged1 and Delta1. Expression patterns showed considerable overlap. No immunoreactivity was detected for Notch2 and Jagged2.

Conclusions

Present findings suggest that Notch receptors and their ligands play differential roles in the cytodifferentiation of SOT.     

Morphological study of the asymmetrical buccal cavity of the flatfish common solea (Solea solea) and its relation to the type of feeding

Objective

To investigate the surface architecture of the asymmetrical buccal cavity of Solea solea which are considered one of the most important predators in benthic communities.

Methods

Adult Solea solea were obtained from Mediterranean Sea near Damietta. The heads were removed and processed for scanning electron microscopy. Its buccal cavity is asymmetrical and divided into roof and floor and the tongue for histological studies.

Results

The buccal cavity roof is formed from upper jaw, velum and the palate. The upper jaw has several wing like processes with teeth arranged in several rows which may help in cutting and pushing the food to the entrance of the digestive canal while the floor is formed from the lower jaw and the tongue. The tongue is divided into apex, body and root. There is a gradual decrease of goblet cells in the tongue from anterior to posterior. These goblet cells function in protection of the epithelium.

Conclusions

Teeth in the floor of the buccal cavity and taste buds can be considered adaptive changes of the oral cavity related to the feeding habits and was a source to identify new and better methods of nutrition in aquaculture of Solea solea.     

Role of computed tomography before lumbar puncture: a survey of clinical practice

Introduction

It is becoming increasingly common to request computed tomography (CT) to rule out space occupying lesions before lumbar puncture (LP), even in patients with no clinical signs. Imaging trends within a busy district general hospital in Oxfordshire, UK were analysed with results used to clarify when imaging should be considered mandatory.

Method

A retrospective six month sample was obtained comprising all adults considered for LP. Observed frequencies of abnormal examination findings compared with abnormal investigations were used to determine sensitivity, specificity, positive predictive, and negative predictive values to assess the validity of using a normal clinical examination as a basis for excluding CT.

Results

64 patients were considered for LP. In total, 58 patients underwent LP, with a single patient receiving two. After an abnormal CT scan, six patients did not undergo a planned LP. In all six of these cases subarachnoid haemorrhage was detected, and in all cases this was considered a probable diagnosis. In no case was an LP precluded by an unsuspected space occupying lesion. Neurological examination showed a sensitivity of 0.72 (0.52 to 0.93), specificity 0.78 (0.64 to 0.91), positive predictive value 0.61 (0.41 to 0.83), and negative predictive value 0.85 (0.73 to 0.97).

Discussion

The high sensitivity and negative predictive values support normal neurological examination as an effective predictor of normal CT scan. This permits the recommendation in cases where subarachnoid haemorrhage is not suspected, a CT scan can be avoided provided there are no abnormal findings on physical or fundoscopic examination.     

Three dimensional reconstruction of the pancreas based on the virtual Chinese human--female number 1

Objective

To study the three dimensional (3D) reconstruction and 3D visualisation of the pancreas and create anatomy of the digitalised visual pancreas so as to construct a concrete basis for virtual operation and surgical operation on pancreas.

Methods

The digital imaging data of pancreas, duodenum, common bile duct, arteries, and veins were obtained from the virtual Chinese human—female 1 (VCH‐F1). The image data were investigated and 380 images ascertained of pancreas picked up from images numbers 2617 to 2996. Finally, the images from number 2574 to 3017 were adopted to segment and processed using ACDSee and Photoshop so as to reconstruct 3D pancreas digitally. The data of pancreatic surfaces were transformed into Visualization Toolkit (VTK). The GUI program written with VC+ was used to display this VTK file and realise 3D visualisation of the pancreas.

Results

3D reconstruction and visualisation of the pancreas and the peri‐pancreatic structures (the duodenum, the common bile duct,the inferior vena cava, the portal vein vessels, the aorta, the coeliac trunk vessels) was successful. The 3D and visualised pancreas manifested itself with its complete structure as well as its adjacency to other tissues.

Conclusion

The 3D reconstruction and 3D visualisation of the pancreas based on the digital data of VCH‐F1 produces a digitally visualised pancreas, which promises a novel method for virtual operation on the pancreas, clinical operation on the pancreas, and anatomy of 3D visualised pancreas.     

Research and applications: Investigating the link between radiologists’ gaze,diagnostic decision,and image content

Objective

To investigate machine learning for linking image content, human perception, cognition, and error in the diagnostic interpretation of mammograms.

Methods

Gaze data and diagnostic decisions were collected from three breast imaging radiologists and three radiology residents who reviewed 20 screening mammograms while wearing a head-mounted eye-tracker. Image analysis was performed in mammographic regions that attracted radiologists’ attention and in all abnormal regions. Machine learning algorithms were investigated to develop predictive models that link: (i) image content with gaze, (ii) image content and gaze with cognition, and (iii) image content, gaze, and cognition with diagnostic error. Both group-based and individualized models were explored.

Results

By pooling the data from all readers, machine learning produced highly accurate predictive models linking image content, gaze, and cognition. Potential linking of those with diagnostic error was also supported to some extent. Merging readers’ gaze metrics and cognitive opinions with computer-extracted image features identified 59% of the readers’ diagnostic errors while confirming 97.3% of their correct diagnoses. The readers’ individual perceptual and cognitive behaviors could be adequately predicted by modeling the behavior of others. However, personalized tuning was in many cases beneficial for capturing more accurately individual behavior.

Conclusions

There is clearly an interaction between radiologists’ gaze, diagnostic decision, and image content which can be modeled with machine learning algorithms.