SA Journal of Radiology - Volume 18, Issue 1, 2014
Volume 18, Issue 1, 2014
Source: SA Journal of Radiology 18, pp 1 –4 (2014) http://dx.doi.org/http://dx.doi.org.10.4102/sajr.v18i1.654More Less
Compound palmar ganglion, or chronic flexor tenosynovitis, most commonly of tuberculous origin, is a rare extrapulmonary manifestation of tuberculosis (TB). The flexor synovial sheath is not a common site for TB but, once involved, causes rapid involvement of all flexor tendons. We discuss the case of a 70-year-old farmer who presented to us with pain and progressive swelling of the palmar aspect of the wrist. On clinical examination, swelling both above and below the proximal wrist crease was found, with positive cross-fluctuation. On ultrasonography and magnetic resonance imaging, features suggestive of compound palmar ganglion were present. The patient underwent surgical resection (extensive tenosynovectomy) and chemotherapy. Post-operative histopatholgical findings correlated with the radiological features.
Source: SA Journal of Radiology 18, pp 1 –4 (2014) http://dx.doi.org/http://dx.doi.org/10.4102/sajr.v18i1.587More Less
Renal lymphangiectasia is a very rare benign disorder characterised by dilatation of the perirenal and peripelvic lymphatics. The condition is commonly misdiagnosed for other cystic lesions of the kidney such as polycystic kidneys. The diagnosis can be made with near-certainty if classical imaging findings are recognised. We report a case of bilateral renal lymphangiectasia, diagnosed on ultrasonography and computed tomography based on the typical imaging findings and the laboratory analysis of aspirated fluid. The patient was managed conservatively.
Source: SA Journal of Radiology 18, pp 1 –4 (2014) http://dx.doi.org/http://dx.doi.org/10.4102/sajr.v18i1.673More Less
A 68-year-old obese man underwent computed tomographic colonography (CTC) scanning to investigate worsening constipation and lower abdominal discomfort on his left side. Optical colonoscopy was contraindicated because of his comorbidities. A preliminary CTC diagnosis of incarcerated Spigelian hernia was made, based on lateral deviation of the sigmoid colon to the left as well as extrinsic impressions on it, and the central location of the small bowel. Spigelian hernia is a rare form of anterior abdominal wall hernia. CTC can play a role in its diagnosis.
Current radiological strategies for the assessment of right lower quadrant abdominal pain : review articleSource: SA Journal of Radiology 18, pp 1 –15 (2014) http://dx.doi.org/http://dx.doi.org.10.4102/sajr.v18i1.695More Less
Right lower quadrant abdominal pain is a common clinical entity. Imaging and the radiologist play an integral role in achieving a diagnosis, so guiding prompt management of patients. This review discusses the spectrum of pathology and imaging findings, and highlights and contrasts the preferred imaging modalities in different subsets of patients.
An approach for performing a successful computed tomography colonography examination : review articleSource: SA Journal of Radiology 18, pp 1 –11 (2014) http://dx.doi.org/http://dx.doi.org/10.4102/sajr.v18i1.607More Less
Computed tomography colonography (CTC) is a minimally invasive, fast, safe and accurate screening examination for colorectal cancer. It also allows evaluation of structures outside the colon. A successful CTC examination requires good bowel preparation, adequate patient hydration, tagging agents, the use of automated carbon dioxide insufflation, and correct positioning for two view and additional view scans. Knowledge of polyp morphology and measurement of polyps are important when interpreting 2D or 3D scans.
The impact of optic nerve movement on optic nerve magnetic resonance diffusion parameters : original researchSource: SA Journal of Radiology 18, pp 1 –5 (2014) http://dx.doi.org/http://dx.doi.org/10.4102/sajr.v18i1.596More Less
Background : Optic nerve diffusion imaging is a useful investigational tool of optic nerve microstructure, but is limited by eye-movement-induced optic nerve movement and artifacts from surrounding cerebrospinal fluid, fat, bone and air. Attempts at improving patient cooperation, thus voluntarily limiting eye movement during a standard diffusion imaging sequence, are usually futile. The aim of this study was to establish the impact of optic nerve movement on clinical diffusion parameters of the optic nerve.
Method : Twenty-nine healthy volunteers with intact vision and intact conjugate gaze were recruited and subjected to magnetic resonance diffusion-weighted imaging (DWI) and diffusion-tensor imaging (DTI) of the optic nerves. Twenty right eyes had nerve tracking done using single-shot echo-planar imaging at 20 time points over 3 minutes. Optic nerve movement measurements were correlated with diffusion parameters of apparent diffusion coefficient (ADC), mean diffusivity (MD), fractional anisotropy (FA) and anisotropic index (AI) using Spearman's rank correlation.
Results : No significant correlations were noted between optic nerve movement parameters and ADC in the axial plane and MD of the optic nerve. Low to moderate negative correlations were noted between optic nerve movement parameters and AI and FA and positive correlation with ADC in the radial plane.
Conclusion : Optic nerve movement documented during the timespan of standard diffusion sequences (DWI and DTI) has a negative effect on the anisotropic diffusion parameters of the optic nerve. With greater eye movement, optic nerve diffusion appears less anisotropic owing to greater radial diffusion.
Source: SA Journal of Radiology 18, pp 1 –4 (2014) http://dx.doi.org/http://dx.doi.org.10.4102/sajr.v18i1.603More Less
Background : The accepted threshold for normal endometrial thickness is 5 mm; lesions with endometrial thickness < 5 mm are considered benign, whilst those > 5 mm are considered malignant. However, endometrium ≥ 5 mm on transvaginal ultrasonography in postmenopausal woman is considered as asymptomatic endometrial thickening. However, recent studies suggest that asymptomatic endometrial thickness of even 8 mm - 11 mm in postmenopausal women may be normal.
Objectives : The present study investigated the normal endometrial thickness range in 297 asymptomatic postmenopausal women using 3.0-T magnetic resonance imaging (MRI) T2-weighted sagittal images measured retrospectively by a single radiologist.
Method : The data were classified according to patient age and postmenopausal duration, and the medical records and follow-up MR images were reviewed to assess the clinical outcome.
Results : The mean endometrial thickness was 2.4 ± 0.1 mm (range: 0.1-11.6). The endometrium in 21 of 297 subjects was ≥ 5 mm thick. Follow-up MR images were obtained in 17 of these 21 women, and their endometrial thickness was found to have decreased in all of them. To date, none of the subjects has been diagnosed with endometrial cancer.
Conclusion : Although 5 mm is considered the conservative threshold of normal endometrial thickness on MRI of postmenopausal women, this figure should not, to avoid excessive false-positive diagnoses, be assumed as an indication of malignancy.
An audit of elective outpatient magnetic resonance imaging in a tertiary South African public-sector hospital : original researchSource: SA Journal of Radiology 18, pp 1 –5 (2014) http://dx.doi.org/http://dx.doi.org/10.4102/sajr.v18i1.689More Less
Background : Increasing demand for magnetic resonance imaging (MRI) has resulted in longer waiting times for elective MRI, particularly in resource-limited healthcare environments. However, inappropriate imaging requests may also contribute to prolonged MRI waiting times. At the time of the present study, the waiting time for elective MRI studies at Tygerberg Hospital (TBH), a tertiary-level public-sector healthcare facility in Cape Town (South Africa), was 24 weeks.
Objectives : To document the nature and clinical appropriateness of scheduled TBH outpatient MRI examinations.
Method : A retrospective analysis of the referral forms of all elective outpatient MRI examinations scheduled at TBH from 01 June to 30 November 2011 was conducted. Patient age, gender, clinical details, provisional diagnosis, examination requested and referring clinician were recorded on a customised data sheet. Two radiologists independently evaluated the appropriateness of each request by comparing the clinical details and the provisional diagnosis provided with the 2012 American College of Radiology (ACR) guidelines for the appropriate use of MRI.
Results : Four hundred and sixty-six patients (median age 42 years; interquartile range 19-55) who had 561 examinations were scheduled in the review period; 70 (15%) were children less than 6 years old. Neurosurgery (n = 164; 35%), orthopaedic (n = 144; 31%), neurology (n = 53; 11%) and paediatric (n = 27; 6%) outpatients accounted for the majority (81%) of referrals; 464 (99.6%) were from specialist clinics. MRIs of the spine (n = 314; 56%), brain (n = 152; 27%) and musculoskeletal system (n = 70, 13%) accounted for more than 95% of the investigations. In 455 cases (98%), the referral was congruent with published ACR guidelines for appropriate MRI utilisation.
Conclusion : Scheduled outpatient MRI examinations at TBH reflect optimal clinical use of a limited resource. MRI utilisation is largely confined to traditional neuro-imaging. Any initiative to decrease the elective MRI waiting time should focus on service expansion.
Author Eleanor A. OchodoSource: SA Journal of Radiology 18, pp 1 –2 (2014) http://dx.doi.org/http://dx.doi.org/10.4102/sajr.v18i1.712More Less
The use of technologically based imaging tests to diagnose diseases and lesions is a fundamental function in radiology. Such tests must be evaluated before their introduction, and during their routine use, in clinical practice to ensure that their performance remains constant. One way of measuring the performance of a medical test is by evaluating its accuracy. Accuracy is defined as the ability of a test to correctly distinguish those subjects who have a target condition from those who do not. A target condition can be the presence or stage of a disease or infection. Accuracy is commonly measured by parameters such as sensitivity (the probability of a positive test result amongst those with disease) and specificity (the probability of a negative test result amongst those without disease). Other parameters include predictive values, likelihood ratios and area under the receiver operating characteristic (ROC) curve. In research, the accuracy of a test is estimated by comparing the results of the test of interest (index test) with the results of the best available test (reference test). For instance, one may wish to estimate the accuracy of chest radiographs in detecting a chest lesion. This may be done by subjecting a sample of patients to chest radiography and to computed tomography (CT) scanning, which is the best available test. Chest radiographs can then be compared with CT scans.