SA Journal of Radiology - Volume 16, Issue 2, 2012
Volume 16, Issue 2, 2012
Source: SA Journal of Radiology 16, pp 44 –47 (2012)More Less
Background. Image post-processing gives computed radiography (CR) a considerable advantage over film-screen systems. After digitisation of information from CR plates, data are routinely processed using manufacturer-specific software. Agfa CR readers use MUSICA software, and an upgrade with significantly different image appearance was recently released: MUSICA2.
Aim. This study quantitatively compares the image quality of images acquired without post-processing (flatfield) with images processed using these two software packages.
Methods. Four aspects of image quality were evaluated. An aluminium step-wedge was imaged using constant mA at tube voltages varying from 40 to 117 kV. Signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) were calculated from all steps. Contrast variation with object size was evaluated with visual assessment of images of a Perspex contrast-detail phantom, and an image quality figure (IQF) was calculated. Resolution was assessed using modulation transfer functions (MTFs).
Results. SNRs for MUSICA2 were generally higher than the other two methods. The CNRs were comparable between the two software versions, although MUSICA2 had slightly higher values at lower kV. The flatfield CNR values were better than those for the processed images. All images showed a decrease in CNRs with tube voltage. The contrast-detail measurements showed that both MUSICA programmes improved the contrast of smaller objects. MUSICA2 was found to give the lowest (best) IQF; MTF measurements confirmed this, with values at 3.5 lp/mm of 10% for MUSICA2, 8% for MUSICA and 5% for flatfield.
Conclusion. Both MUSICA software packages produced images with better contrast resolution than unprocessed images. MUSICA2 has slightly improved image quality than MUSICA.
Radiation protection and the safe use of X-ray equipment : laws, regulations and responsibilities : opinionSource: SA Journal of Radiology 16, pp 50 –54 (2012)More Less
Background. South Africa's regulatory framework for electromagnetic medical devices has come under considerable criticism. Here it is reviewed in terms of how it has given form to protective measures against ionising radiation. The Hazardous Substances Act provides for effective protection against radiation, but has been undermined by poor administration and uncertainty about regulations and licensing conditions. The legal weight of enforcing licensing conditions through a website without proper consultation with all parties concerned is questionable and ineffective. Effective and legal radiation control is possible by activating the National Advisory Committee on Electronic Products, provided for in Regulation R326 published in 1979, but this has never been implemented. The possible impact of annual quality assurance tests currently enforced through licensing conditions on radiation dosage to the population is not cost-effective, as new training and accreditation structures have to be created.
Conclusions. That more than 80% of overexposures are generally caused by human error is a clear indication that training of the regular users of X-ray equipment should be emphasised, and not the training and accreditation of the technicians responsible for a single quality assurance test per year. Constructive engagement with the professional bodies involved in the medical use of X-rays through a National Advisory Committee on Electronic Products may be a cost-effective solution for lowering radiation dosage to the population.
Experiences of using a single post-contrast CT scan of the chest after biphasic contrast injection : pictorial interludeAuthor P.C. PretoriusSource: SA Journal of Radiology 16, pp 56 –60 (2012)More Less
Computed tomographic (CT) chest investigations can be enhanced; in many cases, the arterial phase of a post-contrast arterial and delay (60 seconds) study can be omitted when planning the contrast injection and scanning technique carefully. A biphasic contrast injection was used before starting a single 60-second post-contrast scan.
Source: SA Journal of Radiology 16, pp 61 –64 (2012)More Less
The role of magnetic resonance imaging (MRI) in screening for breast cancer and its use after the diagnosis of breast cancer is discussed. The topic is enormous, with over 5 000 papers published in the last 10 years. In this précis, we focused on articles that examine its clinical relevance. We did not look at economic factors.
Source: SA Journal of Radiology 16, pp 65 –67 (2012)More Less
Dislocation of the ulnar nerve with snapping triceps syndrome has been implicated as a cause of cubital tunnel syndrome. Patients with this condition may clinically present with a snapping sensation at the elbow upon flexion along with ulnar neuropathic symptoms. Though demonstration of this condition is possible by static MRI images, ultrasound can be used as a more accessible and inexpensive modality for attaining diagnosis. This pictorial essay emphasises the technique, findings and role of dynamic ultrasound in the diagnosis of this entity.
Source: SA Journal of Radiology 16, pp 69 –71 (2012)More Less
A ventriculoperitoneal (VP) shunt is a fairly common and useful procedure to reduce intracranial pressure in patients with hydrocephalus. Complications associated with VP shunts are usually related to either shunt obstruction or infection. A pseudocyst formation owing to leakage of CSF into the breast tissue as a complication of VP shunting is a rare entity, with few cases in the literature. Nonetheless, it is an important cause of cystic breast lump and should be kept in mind in a patient with an indwelling VP shunt. We describe the case of a 16-year-old girl patient with an indwelling VP shunt who presented with a gradually increasing breast lump, and was diagnosed to have a CSF pseudocyst based on characteristic imaging findings.
Author Kiran GangadharSource: SA Journal of Radiology 16, pp 72 –73 (2012)More Less
Retrograde jejunogastric intussusception is a well-recognised, rare, but potentially fatal long-term complication of gastrojejunostomy or Billroth II reconstruction. Only about 200 cases have been reported in the literature to date. Diagnosis of this condition is difficult in most cases. To avoid mortality, earlydiagnosis and prompt surgical intervention is mandatory. Since gastrojejunostomies with vagotomy are on a declining trend, it is extremely rare to come across such a complication. We report on such a patient who presented with haematemesis.
Source: SA Journal of Radiology 16, pp 74 –76 (2012)More Less
Pycnodyostosis is a rare autosomal recessive disorder that manifests as generalised osteosclerosis of the skeleton as a result of decreased bone turnover. Patients tend to suffer from numerous fractures owing to dense, abnormally brittle bones. The syndrome has a number of characteristic clinical and radiographic signs that differentiate it from other osteosclerotic conditions. This report is of a young man with a history of long bone fractures.
Source: SA Journal of Radiology 16, pp 77 –78 (2012)More Less
Cubital tunnel syndrome is the second most common peripheral neuropathy of the upper limb. This is due to the anatomy of the tunnel, the physiological changes that the nerve undergoes during elbow flexion, as well as pathological conditions that occur within the tunnel. We present two cases of ulnar neuropathy occurring at the level of the cubital tunnel, demonstrating that this entity may occur owing to an identifiable cause or may show only signal alteration without a visible cause on MRI.
Author S.K. MisserSource: SA Journal of Radiology 16 (2012)More Less
Source: SA Journal of Radiology 16 (2012)More Less
Source: SA Journal of Radiology 16, pp 81 –83 (2012)More Less
CME Fund donates books to Red Cross War Memorial Children's Hospital
First RSSA / SASPI Paediatric Imaging Congress
European Congress of Radiology 2013
RSSA CME educational grants
PET/CT scanner in service at Tygerberg Hospital
Report on the first RSSA-Leuven HRCT Lung Course: 24 - 26 February 2012, Spier Estate, Stellenbosch