Medical practices

Understanding and responding to pharmaceutical promotion. Mintzes B, Mangin D, Hayes L (editors). Amsterdam: Health Action International Global and World Health Organization, 2010 (online, free). THIS BOOK is a collaborative project by Health Action International Global — an organisation based in Amsterdam and committed to promoting the rational use of medicines — and to increasing access to essential medicines, and the World Health Organization. The editors (Barbara Mintzes, Assistant Professor in the Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Canada; Dee Mangin, Director of the Primary Care Research Unit at the University of Otago in New Zealand; and freelance scientific editor Lisa Waller-Hayes) all have a background in writing about pharmaceutical promotion. Information on the influence of promotion on medicine use is often lacking. This book is an attempt to remedy this by bringing together studies on various aspects of promotion, including medical journal advertisements, sales representatives, conference sponsorship, physician opinion leaders and direct consumer advertising. There are contributions from many countries including Australia, a world leader in promoting the rational use of medicines. Health professionals are the target of aggressive and sustained promotional pressure by the pharmaceutical industry but are often not sufficiently educated about understanding and responding to such promotion. This book is intended to fill this gap, and it does so admirably. It also teaches readers the importance of using unbiased sources of information. It has been designed as part of a student module on pharmaceutical promotion, but the easy-to-read style incorporating pictures, graphs and well designed boxes and logical organisation ensures that it can be read on its own. I am currently using it to conduct small-group activity-based teaching sessions for second-year students and consider it superior to other initiatives I have used. I especially liked the chapters dealing with pharmaceutical sales representatives and how to avoid the “pharmaceutical industry tango”. The references at the end of each chapter are comprehensive, and numerous web links are provided. However, it lacks an index. The book can be freely downloaded from the Health Action International website (www.haiweb.org) and is sure to be of interest to all health professionals.

P Ravi Shankar

Current practice in forensic medicine. John Gall, Jason Payne-James, editors. Oxford: Wiley-Blackwell, 2011 (327 pp, $120.00). ISBN 9780470744871. Recent times have seen a growing interest in forensic medicine among members of the public, although not necessarily among medical practitioners. An involvement in forensic medicine requires more than just a passing interest, and this publication examines aspects of the discipline that apply to both the living and the dead. The editors are both specialists in the field. John Gall is a forensic physician with the Victorian Paediatric Forensic Medical Service in Melbourne and Jason Payne-James is a forensic physician based in the United Kingdom and is editor-in-chief of the Journal of Forensic & Legal Medicine. In this book, they cover many areas of clinical forensic medicine and also touch on aviation disasters, but not toxicology. At least once in their careers doctors are likely to be called upon to give evidence in court. This book includes excellent instructions on how to prepare reports for medicolegal cases. For this alone it is a worthwhile reference text for a medical practitioner. For those who practise forensic medicine relating to the living, as in the case of sexual assault, this book should be required reading — it covers essential areas, such as how to assess, describe and interpret injuries, and how to collect specimens for biological or toxicological purposes. The book goes into some detail about the proper classification and description of wounds. However, it cautions against being too robust in attributing causes for wounds in medicolegal cases unless practitioners have the experience to back their judgement. The editors of this text have compiled an authoritative review of the topic, with contributions from leading international experts in the field. They provide enough detail about the forensic sciences to give practitioners some insight into these areas without attempting to turn them into experts.

Tony F Moynham

DiPHD Diagnostic imaging pathways, an iPad application. University of Western Australia and DIP Team. UWA, 2011 ($25.99). DiPHD is a clinical decision support tool in the form of an iPad application, developed by the University of WA in collaboration with the Royal Perth Hospital. For this review, I loaded the DiPHD app (search the iTunes App Store for “Diagnostic Imaging”) onto an iPad 2 (64 GB wi-fi and 3G). I then ran a comparison on the same iPad against the WA Department of Health website Diagnostic Imaging Pathways (http://www.imagingpathways.health.wa.gov.au/includes), from which the app was developed. With a broadband wi-fi connection, the app was noticeably quicker. The app does not include the Image Gallery or the Normal Anatomy from the website, but it does contain the important “Diagnostic Imaging Pathways” section. It is a valuable resource that my hospital has already adopted as its guideline for imaging pathways. It is difficult to think of an acute clinical condition that is not included. The app content is almost the same as the website, with some slight changes in layout that make it easier to access. The layout is also a little different in that you are presented with an anatomical diagram with pointers to the various conditions. The diagram itself does not serve any real purpose and, in some body areas, appears as a picture next to a list of clinical conditions. Like other pathways, these are also open to some debate. For example, “suspected testicular torsion” is directed to urgent surgery, even though many emergency departments have ultrasound capability to exclude torsion. Medical apps for the iPhone and iPad have become the clear leader for bedside clinical information, and the DiPHD is well constructed and accessible. My advice to potential users is to look at the WA Department of Health website first and decide if Imaging Pathways on an iPad is going to be more useful in your clinical practice. In an office-based practice, would you access an iPad, when the same information is available on your desktop computer? Or, as a clinician or junior doctor seeking information at the bedside, does this app fill a niche? Its utility will depend on your clinical practice.

Robert P Dowsett

The clinical usefulness of laboratory testing of adult patients with venous thromboembolism (VTE) for heritable thrombophilia needs to be critically evaluated. At present, some clinicians use testing to identify patients at higher risk of recurrence (who may benefit from an extended period of anticoagulation beyond the usual 3–6 months) and their relatives at risk of a first VTE episode. As prevalence of heritable thrombophilia is related to age and ethnic origin, the pretest probability of detecting heritable thrombophilia may be low in unselected populations. Interpretation of laboratory results may not be straightforward. Apparent deficiencies of a natural anticoagulant may be due to acute thrombosis and “consumption”, concomitant therapy with heparin and/or warfarin and other clinical factors. The predictive value of recurrent VTE conferred by the most common types of heritable thrombophilia (factor V Leiden and the G20210A prothrombin mutation) is limited. Risk of recurrence associated with deficiencies of a natural anticoagulant is less certain due to their rarity. Clinical risk factors (eg, the presence or otherwise of provoking factor(s) and whether or not the risk factor for VTE is reversible or permanent) appear to be the most important predictors of VTE recurrence. Duration of anticoagulation should be determined by clinical risk factors rather than the presence, or otherwise, of heritable thrombophilia. The benefit of identifying relatives who are carriers of thrombophilia is uncertain, as VTE is a multifactorial disease resulting from the interaction of various risk factors, some well recognised and others as yet unknown.

Wai Khoon Ho MMedSc, FRACP, FRCPA · Graeme J Hankey MD, FRCP, FRACP · John W Eikelboom MSc, FRACP, FRCPA

To the Editor: Two key paradigm shifts are occurring with regard to diagnostic imaging services in Australia that may have far-reaching medicolegal and professional consequences for all doctors, have an impact on patient care and, ironically, increase costs to the health budget. First, the federal government announced a 3-year cost-saving trial in the 2009–10 Budget. Since 1 November 2010, the trial allows doctors to request certain “image-only” radiological investigations without an accompanying radiologist report.1 The investigations attract a lower rebate to cover only the technical component of image acquisition. The changes should not alter the cost to patients as most imaging studies, which currently include radiologist reports, are bulk billed. The trial currently involves chest x-rays and certain facial examinations. The government’s presumption is that for these investigations a radiologist’s assessment is not required and referring practitioners will assume full responsibility for the correct identification and interpretation of all primary, secondary and incidental findings. In doing so, referring doctors will also accept all liability for errors. While the incentive for referrers to request these new item numbers is unclear, the increased risk and responsibility borne by them is obvious. Second, in a measure to mimic the National Health System in the United Kingdom, there is advocacy from some levels of health administration to implement role extension for allied health professionals within diagnostic imaging. This would involve the provision of descriptive reports from non-radiologists with no conclusive interpretation, leaving referring doctors to draw their own clinical conclusions. Error rates for these types of reports are not insignificant when compared with a radiologist’s report.2,3 Disposing of a specialist’s evaluation may delay referral or management, and will again transfer responsibility for errors to the referring doctor.4 The false inference underpinning this model is that general medical and specialist training can be fast-tracked or circumvented without any detriment. The most concerning ramifications from these proposed changes are those for standards of patient care. Reduced radiologist input will result in higher error rates and inaccurate diagnoses;5 will remove the option of clinical discussion regarding difficult cases; and may compromise elements of patient care. Ironically, such medical errors often increase downstream burdens for health systems, negating any short-term cost savings. From a medicolegal perspective, undertaking independent interpretation of images and acting on descriptive reports is a high-risk activity and insurance premiums for doctors may ultimately reflect this.

Nicholas I Brown · Lawrence B Josey

Omission: In “Detecting undiagnosed diabetes using glycated haemoglobin: an automated screening test in hospitalised patients” in the 21 February 2011 issue of the Journal (Med J Aust 2011; 194: 160-164), the following were omitted:

Nyoli A Valentine MB BS · Tariq M Alhawassi BScPharm, MClinPharm · Greg W Roberts BPharm, FSHP, BCPS · Parind P Vora MB BS, MPH · Stephen N Stranks MB BS, FRACP · Matthew P Doogue MB ChB, FRACP

Longer life expectancies lead to increases in the prevalence of age-associated illnesses. The number of Australians with dementia is predicted to rise, from 234 000 in 2009 to over 1 million by 2050, as a result of the increased prevalence of Alzheimer’s disease (AD), the leading cause of dementia in the elderly. Early diagnosis of AD will become more important as disease-modifying therapies emerge within the next decade. Advances in molecular neuroimaging with amyloid-β-specific radioligands for positron emission tomography, aided by magnetic resonance imaging techniques, allow detection of AD years before symptoms of dementia develop. Longitudinal prospective studies, such as the Australian Imaging Biomarkers and Lifestyle (AIBL) study of ageing, will determine the sensitivity and specificity of these analysis techniques for diagnosing AD and predicting cognitive decline.

Kathryn A Ellis BAppSc(Hons), PhD · Christopher C Rowe MB BS, FRACP, MD · Cassandra E I Szoeke MB BS, PhD, FRACP · Victor L Villemagne MD · David Ames MD, FRCPsych, FRANZCP · Gaël Chételat PhD · Ralph N Martins BSc(Hons), PhD · Colin L Masters MD, FRCPath, HonDLitt · Jurgen Fripp PhD · Oscar Acosta PhD · Parnesh Raniga BSc(Hons) · Pierrick T Bourgeat PhD · Olivier Salvado PhD

Objective: To assess the utility of glycated haemoglobin (HbA1c) level as an automated screening test for undiagnosed diabetes among hospitalised patients and to estimate the prevalence of undiagnosed diabetes among hospitalised patients.Design, participants and setting: A 3-month prospective study of all adult patients admitted to a tertiary hospital. An HbA1c test was automatically undertaken on admission for all patients with a random plasma glucose (RPG) level ≥ 5.5 mmol/L. Demographic, admission and biochemical data were obtained from hospital databases. A subset of patients was recruited for an oral glucose tolerance test (OGTT) after discharge.Main outcome measures: Prevalence of undiagnosed diabetes (defined as HbA1c ≥ 6.5% in accordance with International Expert Committee and American Diabetes Association recommendations) and utility of automated HbA1c testing.Results: The prevalence of undiagnosed diabetes was 11% (95% CI, 9.8%–12.4%) (262/2360) during the study period. A further 312 patients with known diabetes were admitted. The prevalence of undiagnosed diabetes was highest in the 65–74-years age group. The HbA1c test cost was $152 per new diagnosis of diabetes. Conservatively assuming an annual incidence of undiagnosed diabetes of 0.8%, the ongoing cost of testing hospitalised patients would be $2100 per new diagnosis of diabetes. RPG testing was not sensitive or specific in diagnosing diabetes. Patients were poorly compliant with the post-discharge OGTT (27% completion rate).Conclusions: HbA1c is a simple, inexpensive screening test that can be automated using existing clinical blood samples. Hospital screening for diabetes needs to be coupled with resources for management in the community.

Nyoli A Valentine MB BS · Tariq M Alhawassi BScPharm, MClinPharm · Greg W Roberts BPharm, FSHP, BCPS · Parind P Vora MB BS, MPH · Stephen N Stranks MB BS, FRACP · Matthew P Doogue MB ChB, FRACP

Dose planning for prostate radiation therapy is performed using computed tomography (CT) scans that provide the electron density information needed for individual patients’ radiation dose calculations. For visualising the prostate and determining the target volume for radiation treatment, magnetic resonance imaging (MRI) gives vastly superior soft-tissue contrast. However, currently, MRI scans cannot be used for dose planning, as they do not provide the electron density information. We aimed to develop an alternative and efficient MRI-only image-based workflow, enabling both organ delineation and dose planning to be performed using MRI, with “pseudo-CT scans” generated from MRI scans supplying the information for dose planning. The feasibility of implementing MRI-based prostate radiation therapy planning is being investigated through collaboration between the clinical and medical physics group at the Calvary Mater Newcastle Hospital/University of Newcastle and the biomedical imaging processing group at the CSIRO (Commonwealth Scientific and Industrial Research Organisation) Australian e-Health Research Centre. Results comparing Hounsfield units calculated from CT scans and from MRI-based pseudo-CT scans for 39 patients showed very similar average values for the prostate, bladder, bones and rectum, confirming that pseudo-CT scans can replace CT scans for accurate radiation dose calculations. MRI-based radiotherapy planning can also be used for tumours in other locations, such as head and neck, and breast cancers.

Peter B Greer PhD · Jason A Dowling PhD · Jonathon A Lambert BSc(Hons) · Jurgen Fripp PhD · Joel Parker BAppSc(MedRadScRadTherap) · James W Denham MD, FRCR, FRANZCR · Chris Wratten MB BS, FRANZCR · Anne Capp FRANZCR, FRCR, MMed(ClinEpi) · Olivier Salvado PhD

Computed tomography coronary angiography is the most reliable diagnostic test for coronary atherosclerosis. Stress testing should be reserved for diagnosis of myocardial ischaemia. Revascularisation, either by stenting or bypass grafts, is commonly performed in patients with stable coronary artery disease but is a double-edged sword. In the presence of ischaemia, revascularisation improves outcomes; in its absence, outcomes are worsened. In current practice, the decision of whether to revascularise is mainly made on the basis of the angiographic appearance of the coronary lesion in question. Physiological assessment of coronary lesions by the use of a pressure wire and measurement of fractional flow reserve (FFR) often shows that lesions thought to be sufficiently severe to warrant stenting or bypass do not cause ischaemia. A recent randomised study has shown that using FFR measurements to guide coronary stenting resulted in a lower use of stents, decreased costs and superior outcomes at 2 years, compared with traditional angiographic assessment alone. We believe that changes to the methods of health reimbursement are needed in both the public and private health systems, to facilitate greater use of FFR measurement.

Richard W Harper MB BS, FRACP, FACC · Brian S Ko MB BS, FRACP

To the Editor: We agree with Mendelson and colleagues1 about the need to ensure radiation doses of computed tomography (CT) are as low as reasonably achievable while maintaining diagnostic quality of the images. Perceived benefit to the patient must be balanced against theoretical small risks from the procedure. The uncertainty surrounding risk estimates at the lower end of the radiation dose range means that it is important for radiologists to take responsibility for monitoring radiation dosimetry. This becomes especially important when imaging young people with chronic disease (such as renal calculi, chronic hepatitis, cystic fibrosis and inflammatory bowel disease), who may have many CT scans while young. As stated by Mendelson et al,1 the theoretical risks are assumed to be cumulative over a lifetime, but diminish significantly the older the person is at time of exposure. We would like to highlight work that the Royal Australian and New Zealand College of Radiologists (RANZCR) has undertaken to support the development of CT scanning standards, professional education, dose optimisation and the establishment of national diagnostic reference levels by the Australian Radiation Protection and Nuclear Safety Agency. CT dose optimisation quality improvement programs have been conducted in Queensland and Victoria. These have been funded through a grant to the RANZCR Quality Use of Diagnostic Imaging (QUDI) Program from the Australian Government Department of Health and Ageing. A dose optimisation project is planned for South Australia in 2011. The RANZCR QUDI program has developed a consumer and referrer information database of diagnostic imaging procedures, including a general item about the theoretical risks associated with ionising radiation. This information is accessible at http://www.insideradiology.com.au and supports informed choices about imaging. While Blecher2 and Mendelson et al1 are correct in indicating that the latest multidetector computed tomography (MDCT) platforms have the potential to deliver acceptably low radiation doses and high-quality images, this is not always seen in practice, based on the evidence from these optimisation programs. Some multiphase MDCT protocols have the potential to give rise to organ doses in the range where there is little doubt that a small increased risk of carcinogenesis exists.3,4 Contrary to the comment made by Blecher,2 our knowledge of the impact of radiation on humans does not arise exclusively from atomic bomb survivors. For example, we have evidence of increased breast cancer risk from patients who underwent multiple fluoroscopic examinations to monitor treatment for tuberculosis.5 Risk estimates from this and other datasets are broadly consistent with those from atomic bomb survivor data. In view of the above, we need to be vigilant in ensuring that CT examinations are clinically justified and, secondly, performed using optimised scanning protocols. Referring practitioners need to know that the potential stochastic effects resulting from CT examinations are cumulative over a lifetime. It is this cumulative effect that is not necessarily trivial.

John C P Heggie · Stacy K Goergen · Michael J Fallon

To the Editor: At a time of apparent increasing concern over radiation exposure, the article by Keijzers and Britton1 unfortunately does not provide any perspective on the clinical necessity of the imaging investigations requested by emergency department doctors. It also contains inaccurate information. Stating that “multidetector CT [computed tomography] scanners have the potential to expose patients to higher radiation doses”, and preceding it with “radiation doses per scan have increased by up to 40%”, is incorrect. CT scanner manufacturers have for some time been producing scanners that have decreased radiation doses by incorporating various techniques,2 including iterative reconstruction (a reconstruction algorithm that corrects image data by using various models, thereby improving CT image quality while reducing radiation dose). The dosage reductions reported by major manufacturers and in the literature2 vary between 25% and 80%. The efficacy of dose-reduction mechanisms and the concepts behind them have been outlined in numerous white papers and scientific articles, leading to the conclusion that “newer scanners have improved technology that facilitates lower patient doses”.3 In their seminal article, McCollough and colleagues caution that “alarmist articles” do the public a disservice. They also state that low-level radiation risk estimates, which are derived primarily from atomic bomb survivors and have considerable uncertainties at low doses (< 100 mSv), give no consideration to the medical benefit of a CT scan.2 While Keijzer and Britton’s research investigated emergency department doctors’ knowledge of radiation exposure, the sample was small, being restricted to one institution, and the study had other limitations, as acknowledged by the authors.1 The alarmist undertones have not been helped by the publication of articles in the lay press, such as “Doctors warned over X-ray risks”.4 The danger is that sensationalising the risks of CT scanning may lead to patients not undergoing scans that are clinically indicated, with consequent patient harm. The Royal Australian and New Zealand College of Radiologists (RANZCR) has issued a position statement on radiation dosage.5 As radiologists, we abide by the ALARA (as low as reasonably achievable) principle, and the RANZCR is actively pursuing ways of decreasing radiation exposure.5 In a clinical context, the risk from CT scans is small compared with health risks arising through other activities. Educating doctors about radiation exposure risks is crucial, but so is up-to-date information and common sense, devoid of sensationalism.

Alain M Lavoipierre

In reply: We thank Lavoipierre for his response to our article.1 He brings up two main points. First, he suggests that our statement that newer computed tomography (CT) scanners emit more radiation is incorrect.2 We acknowledge that actual absorbed doses for exactly the same imaging are lower with newer scanners, but the total exposure of the population may be increasing. In the United States, between 1993 and 2006, the annual number of CT scans increased by more than 10% per year, while the population increased less than 1% per year.3 If some scans are unnecessary for safe clinical care, then unsafe radiation exposure is a consequence. His second point is that we should use common sense and not sensationalise our findings out of concern that some patients may not undergo scans that are clinically indicated. We are surprised by his interpretation of the risk of CT imaging, since we quoted a widely accepted estimate.4 Certainly, for an individual, the absolute risk increase is small and may be outweighed by the benefit the scan can provide. However, patients frequently undergo CT scans on the basis of a questionable clinical indication, or when safer imaging modalities would be superior. These unnecessary scans could be avoided. To that end, we advocate common sense, rational test ordering and appropriate discussion of risks, especially where the expected benefit of CT scanning is limited.

Gerben B Keijzers · Charles J Britton

To the Editor: We read with interest the letter by Baschera et al1 regarding the retrieval of non-permanent inferior vena cava filters (IVCFs) in trauma patients. With the advent of retrievable devices, there has been a renewed interest in the use of prophylactic IVCFs after trauma. Retrievable IVCFs are a particularly attractive option for trauma patients, who are often young, with only a transient predisposition to develop venous thromboembolism (VTE). They theoretically provide prophylaxis against pulmonary embolism (PE) in high-risk patients for whom chemoprophylaxis is contraindicated, while avoiding long-term complications associated with permanent IVCFs. However, we share the authors’ concern about low retrieval rates of IVCFs due to loss of patients to follow-up.2,3 The decision to place an IVCF in a patient who has undergone trauma is based on a risk–benefit ratio. If such decisions are made on the presumption that IVCFs will be retrieved, while in practice many IVCFs are not retrieved, the increasing popularisation of retrievable filters may be under false pretences. At our institution, a level 1 trauma centre, all IVCFs are inserted by interventional radiologists under fluoroscopic guidance. At the time of insertion, patient and device details are entered into a purpose-built IVCF database that is run and maintained by the Department of Radiology. At this time, a follow-up appointment is also booked for the patient to attend the IVCF outpatient clinic run by the interventional radiologists. Here, ongoing VTE risk factors are evaluated and the timing of IVCF retrieval is determined. The timing of IVCF retrieval after trauma is controversial, and the occurrence of PE after retrieval is well documented. The risk period for PE after trauma is difficult to quantify, but likely to extend beyond the discharge date for many patients, especially if ongoing surgery is scheduled. For this reason, our practice is to retrieve IVCFs in the outpatient setting 3–4 months after injury. Prolonged IVCF dwell times must be balanced against the increasing difficulty of retrieval because of IVCF endothelialisation, but we feel that a timeframe of 3–4 months does not compromise retrieval rates. Successful retrieval of filters has been reported up to 317 days after insertion.4 As in the case described by Baschera et al,1 it is not uncommon to find a clot in the filter at the time of attempted retrieval, for which multiple causes have been proposed.5 In this situation, it is our practice to rebook patients for a repeat cavogram and second retrieval attempt after therapeutic anticoagulation for 1–2 months.

Lachlan M Batty · Jim Koukounaras · Stuart M Lyon

Bob Barter, who contributed much to the establishment of gynaecological oncology and neonatal pathology services in Western Australia, died recently in Perth at the age of 85. Bob was born in Perth on 27 January 1925. He was educated at Scotch College, Perth, where he was dux of the school in his final year. As there was no medical school in WA at the time, he studied medicine at the University of Adelaide, completing his undergraduate degree in 1949 and a doctorate (on the pathology of lung disease in premature babies) in 1952. He was then awarded a Nuffield Fellowship to study at King’s College in London. Bob returned to Australia in 1954 and worked briefly as a Senior Lecturer at the University of Adelaide before taking an Assistant Pathologist position at the Royal Women’s Hospital in Melbourne in 1955. When a position as Senior Lecturer at the new Faculty of Medicine at the University of Western Australia became available in 1960, he returned with his family to Perth. He was subsequently appointed Associate Professor and Director of the newly established Pathology Department at King Edward Memorial Hospital for Women (KEMH). Apart from a sabbatical year spent as Visiting Professor at Ohio State University in Columbus, Ohio, in 1967, Bob remained at KEMH. During his time at KEMH, community cytological screening for cervical cancer was initiated in Australia. In its early days, it was viewed with considerable scepticism; indeed, the program in WA almost foundered due to lack of standardisation of laboratory cytological examination and reporting, but Bob took on the training and accreditation of scientific staff to a high standard and the crisis was averted. From 1970 to 1972, he was a consultant to the World Health Organization program that was establishing cytology services in Indonesia. From 1976, Bob played a crucial role in the newly established gynaecological oncology service at KEMH. He conducted weekly Tumour Board multidisciplinary meetings until his retirement, making a major contribution to the management of women with gynaecological cancer. He taught medical undergraduate and postgraduate students throughout his career, and had a long association with the Cancer Council Western Australia, serving as its president from 1974 to 1978. In 1990, he was made a Member of the Order of Australia in recognition of his services to medicine. After retirement in 1985, Bob turned his restless intellect and energy to other pursuits, including farming, travel, foreign languages and reading. The last 10 to 15 years of his life were dogged by failing health, which he faced with great fortitude. A series of strokes left him with increasingly severe dysphasia, and eventually resulted in his being unable to read. Despite his progressive incapacity, Bob remained interested in people and the world, and did not lose his sense of humour. This was in large measure made possible by the unfailing love and support of Lyle, his wife of 57 years. Bob died peacefully in hospital on 12 October 2010. He is survived by his wife Lyle, daughter Ann and son Graham, and predeceased by his older son Michael.

Toby T Nichols · Ian Hammond

Mr D Duck presented with a painful neck and underwent cervical facet and foraminal injections under computed tomography control. He looks happy with the result, which proves that interventional radiology is not quackery.

Derrick G Selby · Claudio Coscia

An 82-year-old man presented to the emergency department with abdominal pain and vomiting. An abdominal computed tomography scan showed a whirl sign around the superior mesenteric vessels (Figure, arrow), suggestive of small bowel volvulus. A whirl is formed by the afferent and efferent loops of the volvulus, with the central portion consisting of tightly twisted bowel and mesentery.1 The latter create swirling strands of soft tissue shadow within a background of mesenteric fat attenuation, giving the appearance of a hurricane on a weather map. Caecal and sigmoid volvulus can also give rise to whirl signs. Laparotomy confirmed mid-gut volvulus with 360° rotation. The patient had an uneventful recovery following derotation of the mesentery.

Debasish Debnath · Peter Frecker

Iron deficiency anaemia (IDA) remains prevalent in Australia and worldwide, especially among high-risk groups. IDA may be effectively diagnosed in most cases by full blood examination and serum ferritin level. Serum iron levels should not be used to diagnose iron deficiency. Although iron deficiency may be due to physiological demands in growing children, adolescents and pregnant women, the underlying cause(s) should be sought. Patients without a clear physiological explanation for iron deficiency (especially men and postmenopausal women) should be evaluated by gastroscopy/colonoscopy to exclude a source of gastrointestinal bleeding, particularly a malignant lesion. Patients with IDA should be assessed for coeliac disease. Oral iron therapy, in appropriate doses and for a sufficient duration, is an effective first-line strategy for most patients. In selected patients for whom intravenous (IV) iron therapy is indicated, current formulations can be safely administered in outpatient treatment centres and are relatively inexpensive. Red cell transfusion is inappropriate therapy for IDA unless an immediate increase in oxygen delivery is required, such as when the patient is experiencing end-organ compromise (eg, angina pectoris or cardiac failure), or IDA is complicated by serious, acute ongoing bleeding. Consensus methods for administration of available IV iron products are needed to improve the utilisation of these formulations in Australia and reduce inappropriate transfusion. New-generation IV products, supported by high-quality evidence of safety and efficacy, may facilitate rapid administration of higher doses of iron, and may make it easier to integrate IV iron replacement into routine care.

Sant-Rayn S Pasricha MB BS, MPH · Stephen C Flecknoe-Brown MB BS, FRACP, FRCPA · Katrina J Allen MB BS, FRACP, PhD · Peter R Gibson MD, FRACP · Lawrence P McMahon MD, BS, FRACP · John K Olynyk MB BS, MD, FRACP · Simon D Roger MD, FRACP · Helen F Savoia MB BS, FRCPA · Ramdas Tampi MB ChB, FRACP, FRCPA · Amanda R Thomson MB BS, FRACP, FRCPA · Erica M Wood MB BS, FRACP, FRCPA · Kathryn L Robinson MB BS, FRACP, FRCPA

Objective: To assess emergency department (ED) doctors’ knowledge of radiation doses associated with diagnostic imaging and to describe their practice with regard to informing patients of risk.Design, participants and setting: Prospective, questionnaire-based observational study in May 2009 among all 110 doctors in the EDs of a 570-bed teaching hospital and a 200-bed district hospital.Main outcome measures: Percentage knowledge score; and frequency of discussing radiation risk with patients, based on responses to three scenarios rated on a visual analogue scale (VAS), where a score of 100 indicates doctors would always discuss it.Results: 96 doctors (87%) completed the questionnaire. The overall mean knowledge score was 40% (95% CI, 38%–43%). Senior doctors scored somewhat higher than junior doctors, but not significantly (42% v 39%; P = 0.75). Over three-quarters of doctors (78%) underestimated the lifetime risk of fatal cancer attributable to a single computed tomography scan of the abdomen. Most doctors (76%) reported never having had any formal training on risks to patients from radiation exposure. The frequency at which doctors would inform patients of the risk of radiation varied greatly depending on the clinical scenario (mean VAS scores, between 38 and 90).Conclusion: Emergency doctors in our sample had a varied knowledge of the risks from radiation exposure, but overall knowledge was poor. Staff should receive education, and the diagnostic imaging request process may need to include information on radiation doses and risks.

Gerben B Keijzers MB BS, MSc(Epid), FACEM · Charles J Britton MB ChB

To the Editor: The article in the Journal by Leach and colleagues highlights workforce shortages in the Australian health care sectors.1 The authors identify 12 clinical professions for which data from the 2006 Australian Bureau of Statistics census show poor retention rates, and warn of the implications for the Australian population of these future shortfalls in the health workforce. However, in our opinion, the imminent workforce shortage in the pathology sector (rather than that in the higher profile specialties) is likely to represent the vulnerable point of first failure of the health care system in Australia. Pathology and diagnostic laboratory medicine are major areas in the health system, with about 70% of medical decisions being based on laboratory test results.2 About 13% of Australia’s federal health budget is allocated to pathology testing, and a similar percentage is allocated from state health budgets. Within pathology laboratories, medical scientists form the single largest professional group, although they are usually unrecognised and overlooked in workforce surveys, as is the case in the article by Leach and colleagues. Medical scientists face these same problems of poor retention within the health workforce, leading to the risk of future shortfalls in laboratory capacity and an inability to provide adequate diagnostic support for the medical system. The potential laboratory capacity shortfall has been accelerated by government policies leading to reduced funding for pathology, and the consequent failure to invest in workforce recruitment, training and development. Such an approach may deliver short-term savings, but is leading to an unsustainable environment due to the lack of an appropriately qualified and trained workforce.3 This problem is not restricted to Australia, but highlights the need for a sustainable and long-term approach to ensuring access to relevant health resources for all Australians.

Tony Badrick · Leslie Burnett · Peter E Graham · Peter P Vervaart

Primary hyperparathyroidism (PHT) complicated by osteitis fibrosa cystica (OFC) — the “classical” form of PHT — is rarely seen today. A 41-year-old woman of Sri Lankan descent presented with persistent pain in her right distal forearm 2 days after chopping vegetables. X-ray revealed a fracture through a lucent lesion within the midshaft of the right ulna. A whole-body bone scan showed numerous abnormalities of the major long bones consistent with OFC (Figure, A). Skeletal x-rays showed widespread lytic lesions with osteopenia and subperiosteal erosions, illustrated here by x-ray of the right hand (Figure, B) where marked subperiosteal bone resorption can be seen; note the ill-defined phalangeal cortex (thick arrow) and erosion of the terminal tufts of the distal phalanges (thin arrow). Skull x-ray showed “salt-and-pepper” demineralisation (Figure, C), best appreciated by the lack of visible vascular markings on the calvarium; lytic lesions are present (arrows). The serum calcium level was 4.22 mmol/L (reference range, 2.13–2.63 mmol/L). Our patient was successfully treated with a parathyroidectomy — 5 months after surgery, bone turnover markers were normal, and 14 months after surgery, bone mineral density, tested at the hip, had increased by 22%.

Anna Lih · Mridula Lewis · John Carter

To the Editor: The prophylactic use of inferior vena cava filters (IVCFs) in trauma patients for whom anticoagulation is contraindicated has markedly increased over the past few years. Their need for caval filtration is usually only transient, and once the risk of venous thromboembolism is deemed to be minimal, it would seem appropriate that IVCFs be retrieved. However, a large number of IVCFs remain in situ, due to either failure of retrieval or lack of follow-up. We observed a case that touches on both of these two major problems associated with IVCF retrieval. A 34-year-old man received a prophylactic IVCF after he had sustained severe pelvic fractures, several undisplaced spinal fractures and a splenic laceration in a motorbike accident. He was deemed to be at high risk of venous thromboembolism, and immediate prophylactic anticoagulation was contraindicated because of his pelvic and splenic injuries. The scheduled IVCF retrieval, 8 weeks after insertion, failed due to technical difficulties. A large clot between the struts of the IVCF (Figure) meant further withdrawal attempts were deemed too dangerous. The patient was informed that he had two options: if the filter remained in situ, he would possibly need lifelong oral anticoagulation; or the IVCF could be surgically removed. Soon after this, the patient was discharged with instructions to continue oral anticoagulation. About 5 months later, at a follow-up consultation with the orthopaedic surgeon about his injuries, the patient expressed his concern about the IVCF and especially about the anticoagulation. He was taking it for no other indication than the IVCF. The radiologist who had inserted the IVCF was contacted, and subsequently removed it without any complications. In the case described here, an initial retrieval attempt was thwarted by filter tilt and a large clot burden. After discharge, the patient was lost to follow-up with respect to the IVCF. Fortunately, this was addressed by one of the specialists involved in management of the patient’s other problems. Without this intervention, the patient may have ended up with the filter permanently in situ, with its attendant risks, and an unwarranted lifetime of anticoagulation. When filters have a significant clot burden, anticoagulation can help dissolve this to the point at which retrieval can be effected safely.1 This case highlights the need for appropriate follow-up after IVCF insertion. Various studies have outlined different follow-up strategies, some using a protocol drawn up in a multidisciplinary team setting,2 others designating a key person (usually the clinician who inserted the filter) to undertake this task.3,4 Both strategies have been shown to reduce the number of patients lost to follow-up. The clot, occluding nearly the whole lumen of the inferior vena cava (IVC), is seen as a radiolucent area between the IVC filter struts as the contrast agent passes by.

Dominik Baschera · Jonathan K Sebunya · René Zellweger

To the Editor: Blecher correctly asserts that alarm is not the appropriate reaction to the potential dangers of computed tomography (CT) scans.1 Such alarm risks discouraging patients from having the CT scans they need. Appropriate CT scans are good; inappropriate ones are bad. Blecher is also correct in stating that the linear, no-threshold (no dose is entirely safe however small) model of radiation risk is theoretical.2 However, the advice of all international regulatory radiation protection authorities is to assume that the model is correct. To do so is prudent, even if overly conservative. And while these authorities hold this position, it would be professionally irresponsible to ignore it. Notwithstanding the Health Physics Society statement that the risk of ionising radiation below 100 mSv is negligible,3 the risk is thought to be cumulative. Furthermore, a single CT scan of the chest, abdomen and pelvis may expose a patient to 30 mSv or more, and the risk in children and young adults is considered to be 2–3 times greater than the average.4 The atomic bomb data are based on radiation dose levels as low as 5 mSv,5 with the cohort exposed to doses between 5 and 20 mSv showing an 85% chance that the risk is worse than we think and a 15% chance that it is better than we think. Although not statistically significant at the 95% confidence level, these figures indicate that great care is needed. The dimensions of the risks of low-dose radiation are contentious, but are we willing to ignore the danger of accepting Blecher’s argument? It is a Pascal’s wager. Providing we do not spook patients from having necessary scans (and this requires better communication with patients), our possibly over-cautious approach should result in more appropriate use of diagnostic imaging. The benefits go beyond those of limiting unnecessary radiation. Blecher finds it ironic that concerns about the dangers of CT are rising as radiation doses are falling. Doses may be falling, although that depends on where the baseline is drawn. When multidetector CT scanning was introduced, doses rose,6 but if, since then, doses have been falling, there is nothing ironic about this. Doses are falling because of the concern. Whether a patient undergoes an imaging procedure should be subject to the process of justification mandated in the Australian Radiation Protection and Nuclear Safety Agency code of practice.7 If the potential benefit outweighs the risk, the procedure is justified and the examination should proceed, but optimised to ensure that the lowest possible dose of radiation is used to provide diagnostic images — the ALARA principle (As Low As Reasonably Achievable). In summary: If a CT scan is clinically justified, then it should be performed and we should certainly avoid alarming our patients. If a scan is not justified, it should not be performed. We should adhere to the ALARA principle. Whenever appropriate, a non-ionising alternative to CT scans should be considered, particularly for children and young patients.

Richard M Mendelson · Richard A Fox · Nicholas H de Klerk

Functional histology. 2nd ed. Jeffrey B Kerr. Sydney: Mosby Elsevier, 2010 (viii + 512 pp). ISBN 9780729538374. Histology can be a dry subject. In medical curricula, it has suffered variably from overexposure to underexposure, to the point where graduates may feel perfectly comfortable identifying normal tissues under the light microscope, or squirm uncomfortably when confronted with the same at a multidisciplinary meeting. Finding a balance between pure information and visual references can be difficult and, to paraphrase Elvis, the reader is likely to plead, “a little less longwinded text, a few more pictures please”. The second edition of Functional histology, by Jeffrey Kerr, strikes a good balance. The book has numerous clear, vivid light micrographs, excellent electron micrographs, and superb drawings and diagrams aimed at describing and explaining the organisation and function of body tissues. Traditionally laid out in systems, the text tells an interesting story for each organ, taking the reader through the structure, microscopic appearance, physiology, and function of each tissue, before delineating common abnormal conditions and clinical features. Kerr, an Associate Professor of Anatomy and Developmental Biology at Monash University in Melbourne, says he prepared Functional histology for “those with an interest in biological science as applied to the health professions and for the research community”. The book more than accomplishes this goal, being suitable for a range of users from medical students and pathology registrars through to researchers in the biological sciences. It is distinguished from other works in the discipline by the use of concise, plain language. The useful, friendly “tips”, scattered throughout the text, further engage the reader. The addition of topical references to molecular biology keep the content current and this, together with the text’s accessible style, will maintain the interest of those returning to histology for the purposes of research or postgraduate study.

Tanya Grassi

Objective: To determine whether rates of pathology test ordering by general practitioners in general practices co-located with pathology collection centres (PCCs) are higher than those of GPs in practices located apart from PCCs.Design, setting and participants: We identified all practices in the Melbourne and Sydney metropolitan areas that were co-located with PCCs (same or immediately adjacent suite) and the date co-location was established. This information was merged with the Bettering the Evaluation and Care of Health database to identify samples of GP–patient encounters in co-located practices (n = 31 700) and practices located apart from the nearest PCC (n = 289 700) over the period 2000–2009. Using Poisson regression analysis and logistic regression analysis, we compared GP test-ordering rates across the two types of practices, controlling for a range of potential confounders.Main outcome measures: Numbers of tests ordered per encounter; likelihood of ordering one or more tests per encounter.Results: In unadjusted analyses, GPs in co-located practices ordered more pathology tests than GPs in practices located apart from PCCs (40.3 v 37.0 tests per 100 encounters, P = 0.01) and had a higher likelihood of ordering one or more tests (16.8% v 15.5% of encounters, P < 0.01). After adjusting for other predictors of test ordering, however, neither test-ordering rate (rate ratio, 0.98; 95% CI, 0.93–1.05; P = 0.56) nor likelihood of ordering one or more tests per encounter (odds ratio, 1.01; 95% CI, 0.95–1.07; P = 0.79) differed significantly by co-location status. Sub-analyses within specific test groups and types showed few systematic differences.Conclusions: Pathology test-ordering rates are not higher in practices co-located with PCCs. To the extent inappropriate commercial influences and relationships exist in the pathology sector, GPs’ test-ordering behaviour may be unaffected.

David M Studdert LLB, ScD, MPH · Helena C Britt PhD · Ying Pan BMed, MCH · Salma Fahridin BAppSc(HIM), MHSc(CDM) · Clare F Bayram BAppSc(HIM)(Hons) · Lyle C Gurrin PhD