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.     

Spiral CT Angiography: Applications in Neurovascular Imaging

Background

The advent of Spiral Computed Tomographic (CT) angiography has provided the patients a non-invasive, accurate and fast modality of imaging the vasculature.

Methods

Spiral CT angiography was performed in 30 patients to evaluate intracranial circulation using standard protocols of data acquisition. The images were processed and reconstructed in 3-dimension to delineate anatomy and pathology accurately.

Results

The study established that CT angiography is an accurate modality for evaluating the intracranial circulation in a variety of abnormalities. It is safe both in terms of being non-invasive and exposure to radiation. It has a distinct advantage over other non-invasive modalities of imaging like MRI in the evaluation of patients with metallic stents and clips.

Conclusion

CT angiography has tremendous potential in imaging the intracranial vasculature. It is unquestionably safer than catheter angiography as it avoids arterial puncture and intra-arterial catheter manipulation. It is fast and capable of producing excellent 3-dimensional images of the intracranial vasculature.Key Words: Neurovascular imaging, Spiral CT, CT Angiography     

Anaesthesia for Paediatric Cardiac MRI

Background

General anaesthesia (GA) for cardiac magnetic resonance imaging (MRI) in patients with congenital heart disease (CHD) is challenging for the anaesthesiologist.

Methods

A retrospective review of anaesthesia for cardiac MRI between January 2002 and December 2005 was undertaken.

Result

28 children with cardiac disease were subjected to general anaesthesia for cardiac MRI, of which four patients were in ASA Grade I, five in Grade II, seventeen in Grade III and two in Grade IV. Two patients had undergone previous cardiac surgery. All the cases were managed as inpatients, of which 18 had cyanotic cardiac defects (SpO₂ between 65 and 85%). On two occasions scans were interrupted because of low oxygen saturation or haemodynamic instability during GA. No patient was admitted to the hospital for complications related to general anaesthesia though all were kept under observation for two hours before being shifted to ward. Five patients had a brief episode of hypotension/desaturation during the MRI and responded quickly to interventions.

Conclusion

General anaesthesia for cardiac MRI can be administered safely in children with CHD.Key Words: Cardiac MRI, Congenital heart defects, General anaesthesia     

Computed tomography and magnetic resonance imaging of multiple focal nodular hyperplasias of the liver with congenital absence of the portal vein in a Chinese girl: case report and review of the literature

Background

Patients with congenital absence of the portal vein (CAPV) often suffer from additional medical complications such as hepatic tumors and cardiac malformations.

Case presentation

Congenital absence of the portal vein (CAPV) is a rare malformation. We present a case of a 16-year-old Chinese girl with CAPV with multiple pathology-proven hepatic focal nodular hyperplasias (FNHs) and ventricular septal defect (VSD). The CT and MRI features of this case are described, and previously reported cases are reviewed.

Conclusions

CAPV is a rare congenital anomaly and in such patients, clarifying the site of portosystemic shunts, liver disease, and other anomalies is critical for appropriate treatment selection and accurate prognosis determination. Close follow-up, including laboratory testing and radiologic imaging, is recommended for all CAPV patients.     

Valuable Radiographic Tool for Odontogenic Jaw Keratocyst Diagnosis and Surgical Planning

Objective:

To investigate the clinical use of cone beam computed tomography in the diagnosis of patients with odontogenic jaw keratocyst and to guide computer-aided surgical treatment planning.

Methods:

Imaging, image processing, and visualization technologies were used to produce clear diagnosis, provide proper treatment, and formulate favourable prognosis. Cone beam computed tomography was used to collect medical information including site, extent, shape, and other characteristic features of a patient with large odontogenic jaw keratocyst.

Results:

The imaging technique produced excellent results in imaging, image processing and threedimensional (3D) visualization.

Conclusion:

The 3D digital reconstruction model of the odontogenic jaw keratocyst was shown intuitively.     

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.     

Decreased expression and clinical significance of miR-148a in hepatocellular carcinoma tissues

Background

Aberrant expression of microRNA-148a (miR-148a) has been reported in several types of malignancies. However, its expression and clinicopathological significance in hepatocellular carcinoma (HCC) has not been entirely clarified. Our objective was to investigate the clinicopathological contribution of the miR-148a expression in HCC formalin-fixed paraffin-embedded (FFPE) tissues.

Methods

Eighty-nine HCC and their para-cancerous liver tissues were recruited. Total mRNA including miRNA was isolated and miR-148a expression was determined by using real time RT-qPCR. Furthermore, the relationship between the miR-148a level and clinicopathological features was explored.

Results

Significantly lower miR-148a expression in HCC tissues was observed than that in adjacent noncancerous hepatic tissues. miR-148a expression was also correlated to clinical TNM stage, metastasis, status of capsular infiltration and numbers of tumor nodes.

Conclusions

Underexpression of miR-148a might be associated with HCC tumorigenesis and deterioration of HCC. miR-148a might act as a suppressor miRNA of HCC and it therefore has a potential role in prognosis of HCC patients.     

Osteosarcoma of limb bones: a clinical,radiological and histopathological diagnostic agreement at Black Lion Teaching Hospital,Ethiopia

Objectives

To measure the strength of agreement in clinical, radiological and histopathological diagnosis of osteosarcoma in a 5 year study period.

Setting

Addis Ababa University, Black-Lion (‘Tikur Anbessa’) Hospital-BLH, is the country''s highest tertiary level referral and teaching hospital. The departments involved in this study (Radiology, Pathology and Orthopedics) receive referred patients from all over the country.

Methods

All bone tumor patients, presenting to the three departments at BLH between the study period, December, 2003 – March, 2008 were recruited for the study. 51 patients with radiological diagnosis of osteosarcoma of the extremities were identified and their clinical and histopathological diagnoses reviewed in detail. All patients had a clinical examination, plain radiographs and biopsies of the affected part of the extremity. Radiographs of selected difficult cases were discussed at joint orthopedic & radiologic sessions every week. The radiological and histopathological diagnoses made were categorized separately using WHO classification of bone tumors. Strength of agreement between radiological and histopathological diagnoses was measured using Cohen''s Kappa test.

Results

Of the total of 216 bone tumor patients presented and biopsied in the five year period, fifty one (51) had osteosarcoma of extremity bones. Commonest age affected by osteosarcoma was 16 (7–55years) and sex ratio was 1:1. Osteosarcoma was also the single most common clinical, radiological and histological diagnosis made. Considering all bone tumors presented together, the study indicated that radiological diagnosis was confirmed by similar histological diagnosis in 172 out 205 cases (84 %) and the corresponding Cohen''s Kappa value (0.82) showed excellent level of agreement between radiological and histological diagnoses of all bone tumors. The agreement between radiological and histopathological diagnoses of osteosarcoma of the limbs was 84.5%.

Conclusion

There is an excellent agreement between clinical, radiological and histopathological diagnoses of bone tumors in general and osteosarcoma in particular. In setups where there is limited or no histopathological service, joint clinical and radiological decision could lead to a higher degree of accuracy in diagnosis of bone tumors, especially osteosarcoma. Radiological diagnosis of bone tumors at Black Lion Hospital, Addis Ababa is excellent.     

Ethnic variations in the management of patients with acute stroke

Background

There is increasing interest in the management of stroke in ethnic minorities but few studies have considered this issue. This study investigated if differences in acute stroke management exist between a white European and Bangladeshi populations living in London, England.

Methods

All stroke surviving patients discharged over a five year period in a major London teaching hospital based in an ethnically diverse area of inner city London were recruited. Cerebrovascular risk factors, their management, and investigation for acute stroke syndromes were recorded and comparison between white and Bangladeshi cohorts was made. Categorical data were analysed using Fisher''s exact test.

Results

Measurement of cholesterol concentrations are undertaken less often in those from a Bangladeshi background (25%) compared with white Europeans (76%) (p<0.0001). Statin therapy tends to be given less often to Bangladeshis. However, neuroimaging (p<0.05) and echocardiography (p<0.0001) is performed more often in Bangladeshis compared with white Europeans.

Conclusion

There are variations in the management of acute stroke because of ethnicity and these variations could have substantial consequences on secondary rates of cerebrovascular and cardiovascular disease. Whether the reasons for this disparity are attributable to inequity or iniquity of care need to be further investigated perhaps along with the development of ethnicity specific protocols. Overall the management of stroke and its risk factors in either racial group remains lamentable.     

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.     

Prevalence of patent foramen ovale in a consecutive cohort of 261 patients undergoing routine "coronary" 64-multi-detector cardiac computed tomography

Background

A patent foramen ovale (PFO) is strongly associated with cryptogenic stroke (CS), neurological and other phenomena. The reported prevalence of PFO varies according to the imaging technique used and population studied.

Purpose

To measure prospectively, the prevalence of PFO in a cohort of consecutive patients attending for routine “coronary” CT angiography using standard, everyday coronary protocols including low-dose prospective ECG gated studies.

Methods

Standard coronary imaging protocols were used. PFOs were graded according to the classification of Williamson et al.¹

Results

261 patients were studied. A PFO was identified in 22.6% (11.5% grade 1 (closed flap), 6.5% grade 2 (open flap) and 4.6% grade 3 (open flap with jet)). A further 6.1% had an atrial septal aneurysm.

Conclusions

The prevalence of all grades of PFO (22.6%) and open flap PFO (11.1% = grade 2 and 3) with this technique compares with 24.3% by trans-oesophageal echocardiography (TOE) and 14.9% by saline contrast echocardiography (SCE)^{2, 3} Further comparative studies are required but we believe an open flap PFO or ASA should be identified and recorded during cardiac CT. This approach may identify those at risk of cryptogenic stroke as well as avoid unnecessary tests in stroke patients.     

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.     

Comparative analysis of changes in MR imaging of pre and post intrauterine progesterone implants in adenomyosis cases

Background

Magnetic Resonance Imaging (MRI) plays an important role in the evaluation and management of adenomyosis. In this study, we first diagnosed the adenomyosis on MRI and then we analyzed the MRI changes in the uterus in pre and post intrauterine progesterone implants cases.

Method

All the patients with clinical diagnosis of menorrhagia or dysmenorrhea were screened by Ultrasonography (USG) of the pelvis. Patients with heterogeneous echo texture of the uterus were then evaluated by the MRI of the pelvis. All patients with MRI findings suggestive of adenomyosis formed the study group.

Result

On MRI study 60 patients were diagnosed as adenomyosis, 68.33% had diffuse adenomyosis and 31.66% had focal adenomyosis. 83% of diagnosed adenomyosis cases had high intensity signal foci which were seen in 75% cases of diffuse adenomyosis and 100% cases of focal adenomyosis. 50 diagnosed adenomyosis cases were then reviewed after 03 months, 06 months and 12 months to see for any change in the MRI findings in the post intrauterine implant cases. On follow up MRI after post progesterone intrauterine implant, 50% of the cases showed reduction in the high intensity signals, 10% of the cases showed mild reduction in the junctional zone thickness with no significant change in the uterine size.

Conclusions

It is inferred that MR imaging is not only helpful in diagnosing but also helpful in monitoring the effects of hormonal therapy in adenomyosis.     

Utility of N terminal pro brain natriuretic peptide in elderly patients

Objective

To evaluate the utility of N terminal pro brain natriuretic peptide (NT‐proBNP) as a diagnostic marker for diastolic dysfunction or failure, systolic dysfunction, and significant valve disorders in patients over 75 years.

Design

Cohort study.

Setting

Outpatient echocardiography service in a district general hospital.

Participants

100 consecutive patients.

Main outcome measures

Sensitivity, specificity, positive predictive values, negative predictive values, and area under receiver operating characteristic curve for NT‐proBNP assay in the diagnosis of left ventricular diastolic dysfunction or failure, systolic dysfunction, and significant valve disorders.

Results

For diagnosis of systolic dysfunction NT‐proBNP level of 424 pg/ml had a sensitivity of 96%, specificity of 45%, positive predictive value of 36%, and negative predictive value of 96%. The area under the curve was 0.71 (95% confidence intervals: 0.69 to 0.89). In valve heart disease, level of 227 pg/ml had sensitivity of 91%, specificity of 43%, positive predictive value of 40%, and negative predictive value of 92%. Patients with diastolic dysfunction/failure had lower plasma concentrations.

Conclusions

This study showed that NT‐proBNP had excellent negative predictive value for systolic dysfunction and significant valve disorders in very elderly patients. It increased significantly in systolic dysfunction, valve heart disease, and atrial fibrillation. NT‐proBNP is not useful in the diagnosis of diastolic dysfunction or diastolic heart failure using standard echocardiography criteria.     

D-dimer in the diagnostic workup of suspected pulmonary thrombo-embolism at high altitude

Background

Pulmonary thrombo-embolism (PTE) is relatively common in high altitude areas where radiological diagnostic facilities are usually not available. So this study was undertaken to use the results of D-dimer assay to determine the need for imaging studies in patients suspected of having PTE at high altitude.

Methods

A total of 101 patients at an altitude of > 3,000 m suspected of having PTE were evacuated. D-dimer and imaging studies were carried out to confirm the diagnosis.

Results

A total of 101 patients suspected of having PTE underwent D-dimer level estimation and imaging studies for PTE. Sixty-eight of these had negative findings) on D-dimer assay. All these patients with negative findings on D-dimer assay had negative findings on pulmonary imaging studies also. So this test is very sensitive with very high negative predictive value (NPV). Whereas, 17 out of 33 patients positive for D-dimer, had positive findings on imaging studies, indicating a relatively less specific test.

Conclusion

Clinical assessment in combination with D-dimer assay can be used for timely differentiation of PTE from other conditions such as high altitude pulmonary oedema (HAPO) especially at isolated high altitude areas/military posts, so that patients could be evacuated as early as possible by fastest means to save the precious lives and in hospital settings this test identifies patients to whom anticoagulant therapy should not be given or patients who should not be subjected to invasive imaging tests.Key Words: D-dimer test, PTE     

Health Professionals Expose TB Patients to Stigmatization in Society: Insights from Communities in an Urban District in Ghana

Objectives

To determine how the activities and attitudes of health professionals expose TB patients to stigmatization in the community.

Design

Qualitative research approach using individual interviews and focus groups

Setting

Shama Ahanta East Metropolitan district in the western region of Ghana

Participants

Members in nine communities in the district

Outcome measures

Words and statements that depict how activities and attitudes of health professionals may expose TB patients to stigmatization

Results

Five interrelated ways by which activities and attitudes of health professionals may expose TB patients to stigmatization in the community were identified in data: TB control practices; fear-based responses to TB; inappropriate health education messages; medical licensing for sellers; and prohibition of burial rites.

Conclusions

The findings may explain the diagnostic delay and low TB case detection rate in Ghana. This calls for intensification of education on TB and regular organization of refresher courses and possibly retraining of health professionals in TB control and management. When health professionals are seen to be treating TB patients as ‘normal’ individuals, it has the potential of changing the society''s perception about the disease.     

A comparative study of whole body DWIBS MRI versus bone scan for evaluating skeletal metastases

Background

Skeletal metastases in oncology patients are identified by Bone scan and/Positron Emission Tomography (PET) scan. But developing countries in the world still lack adequate numbers of these imaging facilities.

Aims

Since Magnetic Resonance Imaging (MRI) is widely available as compared to bone scan or PET scan; a double blind study was undertaken to see if whole body imaging with MRI can give an idea of skeletal metastases.

Method

Diffusion weighted whole body Magnetic Resonance Imaging with background body signal suppression (DWIBS) was performed using 1.5 Tesla (T) MRI on histopathologically proven cases of carcinoma of breast within two months of mastectomy and followed up after a year of surgery. Similarly bone scan was also performed in these patients.

Results

DWIBS MRI demonstrated the presence and extent of bone metastases in 10 out of a total 18 patients included in study while bone scan could demonstrate them in only three cases. A highly significant difference between proportions of the skeletal metastases detected by whole body DWIBS-MRI than that by bone scan at one year follow-up. (i.e. p<0.01, z=2.66) was seen.

Conclusion

DWIBS MRI scores high in demonstrating skeletal metastases. Further comparative studies are necessary to evaluate if DWIBS can replace bone scan or PET scan.     

Cost-effectiveness Analysis for Technology Acquisition

Background

In a developing country with limited resources, it is important to utilize the total cost visibility approach over the entire life-cycle of the technology and then analyse alternative options for acquiring technology.

Methods

The present study analysed cost-effectiveness of an “In-house” magnetic resonance imaging (MRI) scan facility of a large service hospital against outsourcing possibilities. Cost per unit scan was calculated by operating costing method and break-even volume was calculated. Then life-cycle cost analysis was performed to enable total cost visibility of the MRI scan in both “In-house” and “outsourcing of facility” configuration. Finally, cost-effectiveness analysis was performed to identify the more acceptable decision option.

Result

Total cost for performing unit MRI scan was found to be Rs 3,875 for scans without contrast and Rs 4,129 with contrast. On life-cycle cost analysis, net present value (NPV) of the “In-house” configuration was found to be Rs-(4,09,06,265) while that of “outsourcing of facility” configuration was Rs-(5,70,23,315). Subsequently, cost-effectiveness analysis across eight Figures of Merit showed the “In-house” facility to be the more acceptable option for the system.

Conclusion

Every decision for acquiring high-end technology must be subjected to life-cycle cost analysis.Key Words: Technology assessment, Cost benefit analysis, Cost-effectiveness analysis     

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.