Our RADIOLOGISTS
Providing diagnostic excellence throughout Queensland
Every day our radiologists provide the highest level of care, precision and timeliness in caring for the health and wellbeing of your patients.
With high quality imaging and accurate reporting, our radiology team is there to support you and your patients in receiving the diagnosis needed for the best possible healthcare.
Discover our radiologists
Dr. James Challen
MBBS, FRANZCR
Dr. James Challen obtained his Bachelor of Medicine and Surgery from the University of QLD in 1999. He trained in radiology at Princess Alexandra Hospital Brisbane before going on to complete fellowships in general MRI and cardiac imaging. After completing these fellowships, Dr. Challen became recognised by the college as an MRI supervisor and was accredited by the Australian Conjoint Cardiac Committee to report cardiac CT scans. He moved to the Sunshine Coast in 2009.
Dr. Challen also has an interest in MSK imaging and he currently runs the orthopaedic/Radiology meeting at Nambour Hospital. For many years he has previously run the medical/radiology meeting and Urology/radiology meetings at NGH.
He also has an active interest in research having contributed many talks and posters to the Australian Radiology Scientific meeting. In 2013 he was one of the chief convenors of the QLD radiology scientific meeting. Dr. Challen has been heavily involved in registrar training, first as the director of training at Nambour General Hospital and now as the current director of registrar training at Sunshine Coast Radiology.
Fellowships:
- Fellowship in cardiac imaging (Prince Charles Hospital)
- Fellowship in general MRI (Princess Alexandra Hospital)
Subspecialties:
- Musculoskeletal imaging and procedures
- Cardiac CT
- Breast Imaging
- Prostate MRI
Memberships and accreditation:
- CT Coronary angiogram level B accreditation
- Accredited Breast screen reader with QLD breast screen
- Reports over 5000 mammograms per year
- CT colonoscopy level
Interests:
- MSK imaging
- Breast imaging (MRI, mammography and US)
- Prostate MRI imaging
- Image-guided procedures
Dr. Alan Chai
MBBS, FRANZCR
Dr. Chai graduated in Medicine (with first class honours) at the University of Sydney in 1997. He then completed his radiology training at St George Hospital (SESLHD). A medallist in the final FRANZCR radiology exams in 2004, Dr. Chai then went on to complete an Interventional Radiology Fellowship (with MRI component) at Westmead Hospital (WSLHD).
Dr. Chai has held multiple public hospital appointments in NSW and has been a VMO of BreastScreen NSW since 2007. Since 2012, Dr. Chai has also been working in private practice, including previously as a partner in PRP Diagnostic Imaging. Dr. Chai joined the SRNM team in July 2023.
Dr. Chai is a general radiologist with specialty interests including breast, body and oncology imaging, and interventional procedures including spine injections.
Dr. Anthony Chan
MBBS, FRANZCR
Dr. Anthony Chan obtained his Bachelor of Medicine and Surgery at the University of Tasmania. He undertook radiology training at the Royal Brisbane and Women’s Hospital and has subspecialty interests in cardiac and abdominal imaging including Gastrointestinal and Prostate MRI imaging.
Since coming to the Sunshine Coast in 2007 he divides his time between private practice at Sunshine Coast Radiology and as staff specialist at the Sunshine Coast University Hospital where he is part of the radiology training program. He is also part of the Queensland Breast Screen Program.
Dr. Geoffrey Clark
MBBS, BE, FRANZCR
Dr. Geoff Clark obtained his Bachelor of Medicine and Surgery with Honours from the University of Queensland in 1996.
He trained in radiology at the Royal Brisbane and Women’s Hospital, gaining admittance to the RANZCR in 2006. Currently, Dr. Clark works at our Rockhampton practice and also at Breast Screen Queensland, which includes mammography reading, assessment clinics, and multi-disciplinary meetings.
Previously Dr. Clark worked as a staff radiologist at Nambour General Hospital, where he was the supervisor of registrar training.
Fellowships:
- MRI
- Musculoskeletal Imaging (MSK)
- Interventional Procedures
Dr. Jacqui Dalton
BDSc, DClin, Dent(UQ)
Dr. Jacqui Dalton completed her Dentistry degree at the University of Queensland in 2002. Over the following years, she gained experience as a Dentist in both private and government practice and paediatric dentistry, before completing her Doctorate of Clinical Dentistry in the specialty of Dentomaxillo facial radiology, at the University of Queensland.
Dr. Dalton gives back to the university lecturing both undergraduate and postgraduate radiology for the dental students. With 10 years’ experience in public and private practice, Dr. Dalton also lectures and tutors undergraduate Dentistry students at UQ.
Dr. Tim Demetriades
MBBS, FRANZCR, FAANMS
Dr. Demetriades completed his undergraduate medical training at the University of Queensland and pursued his radiology specialist training at the Mater Public and Princess Alexandra Hospitals in Brisbane Dr. Demetriades became a fellow of RANZCR in 2005. He then went on to complete a fellowship in Nuclear Medicine. He was then further recognised by the college as an MRI supervisor and was accredited by the Australian Conjoint Cardiac Committee to report cardiac CT scans. Dr. Demetriades has worked in a number of private and public hospital and private practice settings. He was the co-founder and Director of X Radiology in Australia in 2008. Dr. Demetriades has subspecialty interest in Musculoskeletal imaging Cardiac CT, Oncology including PET imaging and MRI. Dr. Demetriades performs a range of interventional procedures including cervical, thoracic and lumbar nerve root blocks and facet injections, musculoskeletal injections and biopsies. He is a Fellow of the Royal Australian and New Zealand College of Radiologists and Fellow of the Australian Association of Nuclear Medicine Specialists.
Dr. Shane Diers
MBBS, FRANZCR
Dr Shane Diers graduated from the University of the Witwatersrand, Johannesburg, South Africa, going on to specialise in diagnostic and interventional radiology achieving both FCRad Diag(SA) and FRANZCR.
Prior to joining X-Ray & Imaging in 2019, Dr Diers spent 10 years working in private practice in Johannesburg, and 4 years as a consultant radiologist in the public sector in Whangarei, New Zealand.
Areas of Interest:
- Emergency and trauma imaging
- Diagnostic and interventional musculoskeletal imaging
Dr. Siavash Es'haghi
MB, ChB, FRANZCR
Dr. Es’haghi obtained his medical degree at the University of Otago (NZ) in 1993 and was accepted as a fellow of the RANZCR following his radiology training at the Princess Alexandra Hospital in Brisbane. Dr. Es’haghi’s experience as a radiologist is enhanced through his completion of a Fellowship in Magnetic Resonance Imaging (MRI), with special emphasis on musculoskeletal and breast imaging.
Committed to ongoing professional development, Dr. Es’haghi has involved himself in student and registrar training at the Princess Alexandra Hospital and Rockhampton Hospital. He also has been the supervising MRI radiologist at the Rockhampton and Sunshine Coast Private Hospitals. Dr. Es’haghi is currently the supervising radiologist for Sunshine Coast Radiology. Dr. Es’haghi is accredited at Breast Screen Queensland.
Fellowships:
- MRI
- Breast
- Interventional Procedures
Dr. John Evans
MBBS, FRANZCR, B Med Sci
Dr. John Evans obtained his medical degree from the University of Tasmania in 1988. His Radiology training finished in 1996 and included work at Royal Canberra hospital, Woden Valley Hospital Canberra, Royal Brisbane Hospital, Royal Infirmary and Western General Hospitals Edinburgh. His Nuclear Medicine training was at Princess Alexandra Hospital and Addenbrookes Hospital Cambridge finishing in 2001. He is accredited for PET and CT Coronary Angiography and perform many interventional procedures.
He has spent the last 12 years at Cairns Diagnostic Imaging including 11 years as the manager and MRI supervising radiologist. He has also been the supervising radiologist at Breastscreen QLD Cairns region. He has been lecturing year 4 medical students at JCU and been a clinical examiner. He has given many talks to GPs and other medical groups.
Areas of interest:
- Nuclear Medicine
- MRI
- Breast and prostate imaging and procedures
- Cardiac imaging
Subspecialties:
- General Radiology
- Nuclear Medicine
Memberships and accreditations:
- PET and CT Coronary Angiography
- Breast screen Queensland
- FRANZCR
Fellowships:
- FRANZCR
- Nuclear Medicine Specialist
Dr. Denise Ladwig
FRANZCOG, DDU
Dr. Denise Ladwig is an Obstetrician Gynaecologist and Ultrasound Specialist and works exclusively in women’s imaging, completing her fellowship at the Royal Hospital for Women in Sydney.
She is a Fellow of the Royal Australian and New Zealand College of Obstetricians and Gynaecologists and has a Diploma of Diagnostic Ultrasound.
Dr. Ladwig has worked in both the public and private sector, with consultant appointments including Royal Hospital for Women and St George Private Hospital (Sydney).
She has been an examiner for the Diploma of Medical Ultrasound for the Australasian Society of Ultrasound in Medicine.
Dr. Rodney Larsen
MBBS (Hons), FRANZCR
Dr. Rodney Larsen graduated with honours from the University of Qld. After completing his initial radiology training at the Royal Brisbane and Women’s Hospital (RBWH) he completed a fellowship in MRI/Neuroradiology at the RBWH, and has gone on to undertake further training in Breast Imaging and cardiac CT.
He is a VMO with breast screen Queensland, a cardiac CT accredited specialist, and currently also works at Nambour General Hospital as a staff specialist. He spent several years working in private radiology practice at the Mater Hospitals in Townsville, has been a staff specialist at RBWH and now lives and works on the Sunshine Coast.
Dr. Larsen also has an interest in teaching radiology and has been involved with registrar training as well as working as a lecturer around Australia teaching radiology to other medical professionals.
Fellowships:
- MRI
- Neuroradiology
Accreditations:
- ANZCTCA Accredited Level B CTCA Radiologist
- Breastscreen Qld accredited radiologist
Interests:
Neuroradiology
MSK imaging
Dr. Eugene Lim
MB, FRANZCR, FAANMS
Following graduation from University of Queensland in 1989, Dr. Lim completed his internship, residency and first year as a Radiology Registrar at Greenslopes Repatriation Hospital. He completed his Radiology training at the Royal Brisbane and Women’s Hospital and went on to work in private practice before returning to the Royal Brisbane Hospital in 2001 to train in Nuclear Medicine. He completed his Nuclear Medicine training at Kings College Hospital in London. In June 2010, Dr. Lim opened Lime Radiology where his aim was to provide a high quality, patient-focused, diagnostic imaging service to the northside of Brisbane. In addition to Nuclear Medicine, he has a special interest in breast imaging where he has had extensive experience in diagnostic mammography and breast ultrasound. He is also highly skilled in ultrasound-guided breast biopsies as well as both ultrasound and mammographic-guided breast localisation.
Dr. Noel Marginson
MBBS, FRANZCR
Dr. Noel Marginson graduated MB, BS from the University of QLD in 1970 and, after completing his Radiology training at the Royal Brisbane Hospital, became a Fellow of the RANZCR in 1979.
Dr. Marginson then became a Staff Radiologist at the Royal Brisbane and Women’s Hospital in 1980-81 before entering private practice in Ipswich and Toowoomba, and subsequently moving to the Sunshine Coast in 1985.
In 1991, Dr. Marginson established a radiology practice in Caloundra, adding branches in Beerwah and Caloundra Private Hospital. In 1996, he became a partner in North Coast X-ray and Imaging.
In recent years, Dr. Marginson has worked with Queensland Diagnostic Imaging on the Sunshine Coast and, most recently, with Sunshine Coast Radiology.
Dr. Marginson has previously been an accredited radiologist with Breast Screen QLD and has a particular interest in sports medicine imaging.
Dr. Antonio Pais
MBBS, DNB, FRANZCR
Dr. Antonio Pais joined CitiScan Radiology in 2015, bringing with him extensive experience as a radiologist and educator. Dr. Pais was the Director of Radiology Services for the Mackay Hospital and Health Services for ten years before relocating to Brisbane. Prior to this he was the Director of Training and a Senior Lecturer at James Cook University. Dr. Pais graduated from St. Johns Medical College in Bangalore, India. Following this he completed his post-graduate training in Radiology at Christian Medical College, Vellore, India. He then managed his own diagnostic radiology centre in the state of Goa for 15 years.
Dr. John Salanitri
MBBS, FRANZCR
Dr. Salanitri is based at the Hillcrest Rockhampton Private Hospital.
Dr. Salanitri obtained his Bachelor of Medicine and Surgery with Honours from the University of Queensland in 1992. After working in rural Queensland hospitals for three years, he trained in Radiology at St. Vincent’s Hospital, Melbourne and did an MRI Fellowship at the Alfred Hospital, Melbourne. He was admitted to the FRANZCR in 2002 and did further advanced MRI training in Chicago, returning to Queensland in 2006. Prior to moving to Rockhampton, Dr. Salanitri has worked in private practice on the Sunshine Coast and in Brisbane.
Dr. Salanitri’s professional interests include Musculoskeletal Imaging and MRI.
Dr. Amit Sidana
MBBS, DMRD, FRCR, FRANZCR
Dr. Amit Sidana, FRCR, FRANZCR obtained his early radiology training in India. He then completed The Fellowship of Royal College of Radiology (FRCR) in the United Kingdom and gained admittance to the Royal Australian and New Zealand College of Radiology (RANZCR) in 2013. He has special interests in Neuroimaging and Musculoskeletal imaging and is committed to ongoing professional development in diagnostic radiology.
Fellowships:
- Fellow of Royal College of Radiology, London, UK
- Fellow of Royal Australian and New Zealand College of Radiologists
Areas of Interest:
- Magnetic Resonance Imaging (MRI)
- Musculoskeletal Imaging
Memberships and accreditation:
- AHPRA
- IRIA
- RSNA
- ARRS
Dr. Mark Sinnamon
MBBS, FRANZCR, FAANMS
Dr. Sinnamon graduated from University of Queensland in 1990. He completed his training at the Princess Alexandra Hospital Brisbane and completed further training at the Wesley PET Centre & Nuclear Medicine Brisbane
Mark is a member of Australian and New Zealand Association of Nuclear Medicine Physicians with accreditation in Nuclear Medicine and PET imaging.
Sub-specialists interests:
- Oncology
- Musculoskeletal (MSK) Imaging
Dr. Paula Sivyer
MBBS, FRANZCR
Dr. Paula Sivyer is a renowned specialist in women’s imaging and interventional radiology. She has lectured extensively in the field of women’s imaging and intervention, both nationally and internationally and has been published in the World Journal of Surgery. Dr. Sivyer is also a Part II Viva examiner for the Royal Australian and New Zealand College of Radiologists (RANZCR). Dr. Sivyer is responsible for bringing numerous technologies, as well as imaging and intervention techniques to Australia, including 10-year-comparator digital imaging archive (2004), digital mammography (2007) and Hologic ‘Genius’ 3D mammography, which DIfW was the first to introduce in Australia in 2010.
Dr. Pradeep Sonwalkar
MBBS, FRANZCR
Dr. Sonwalkar graduated Bachelor’s Degree from Mysore, India and completed his Doctorate of Medicine in Radiology in 2010. Dr. Sonwalkar was Assistant Professor for 2 years before relocating to Australia. He gained admittance to RANZCR in 2018 and has over 13 years experience in radiology. He has a keen interest in chest radiology and paediatric imaging.
Dr.Sahm Taheri
MBBS, B Med Sci, FRANZCR
Dr. Sahm Taheri graduated from the University of Tasmania School of Medicine in 2006 before completing his specialist radiology training at Royal Hobart Hospital in 2016. He then completed a Musculoskeletal (MSK) Hybrid Fellowship in Hobart while continuing to advance this subspecialty interest through multiple mini-fellowships and ongoing professional development.
Dr. Taheri also has expertise in advanced cardiac imaging, achieving Level A certification in CT Coronary Angiography (CTCA) in 2021.
He brings broad experience across a wide range of diagnostic imaging services and values close collaboration with referring clinicians to ensure imaging findings support confident clinical decision-making. While most of his career has been spent working in private practice, Dr. Taheri has also worked at Sunshine Coast University Hospital (SCUH).
His clinical interests include musculoskeletal imaging, MRI, image-guided interventional procedures and medical education. Dr. Taheri is passionate about supporting the next generation of radiologists and serves as the Director of Training (DoT), Imaging Queensland, mentoring registrars and developing radiology training programs.
After spending most of his life in Hobart, he’s moved north, chasing the warm weather. He loves the outdoor lifestyle on the Sunshine Coast, which he enjoys with his wife and three energetic young boys. Outside of work he enjoys staying fit, spending time outdoors and attempting to master surfing when time allows.
Dr.Tevita Taka
MBBS, FRANZCR
Dr. Tevita Taka grew up between New Zealand & Fiji before completing his medical training at Otago Medical School. Tevita obtained his RANZCR fellowship at Dunedin Hospital in 2010, before relocating to Australia and joining X-Ray & Imaging in 2011.
Areas of Interest:
- MSK MRI imaging
- MSK interventional procedures
Prof. Hans van der Wall
PhD, FRACP
Professor Van der Wall is Professor of Medicine at Notre Dame University in Sydney. He trained at the Prince of Wales Adult and Children’s Hospital. On completion of his PhD at the University of NSW he took up the position of Director of Nuclear Medicine at Concord Hospital and is now full-time in private practice with 30 years experience as a Nuclear Medicine Specialist. Prof. Van der Wall has supervised 9 PhD students and published over 150 scientific papers in the refereed literature. He has co-authored chapters in 8 textbooks of Nuclear Medicine and is a section Editor of the Musculoskeletal Section of the current reference text of Nuclear Medicine (Ell & Gambhir). Prof. Van der Wall has been the invited speaker at over 70 international and local meetings including the Society of Nuclear Medicine annual meetings in the US and Europe, World Congress on Low Back Pain and the European Thoracic Society Meeting. Hans’ main research interests are in gastroesophageal reflux testing and the diagnosis of lateralising lower back pain. He has developed and patented tests in both areas and his research has been validated against the accepted reference standards.
Dr. Rastie van der Westhuizen
MBBS, FRANZCR
Qualifying as a consultant radiologist in South Africa in 1990, Rastie relocated to Australia with his wife and two sons in 2004 and joined X-Ray & Imaging in 2012.
Areas of Interest:
- Interventional radiology
- CT and ultrasound-guided injections
Dr. John Velkovic
MBBS, FRANZCR
After graduating from the University of Queensland in 2007, Dr John Velkovic completed his radiology training at the Royal Brisbane Women’s Hospital and obtained his FRANZCR qualification in 2015.
John then went on to work at Nambour General Hospital and Sunshine Coast University Hospital for several years before moving into the private radiology sector, working across Sunshine Coast Radiology and X-Ray & Imaging.
Dr. Peter Wakefield
MBBS, FRANZCR
Dr. Peter Wakefield studied medicine at the University of Queensland and undertook his radiology training at the Royal Brisbane and Women’s Hospital. He gained admittance to RANZCR in 2008, following the completion of a Musculoskeletal fellowship.
As a staff specialist radiologist at Nambour General Hospital, Dr. Wakefield’s duties cover a wide range of sub-specialty areas utilising all modalities, including MRI.
His skills and knowledge of radiology are continually updated through his contribution to the registrar training program and his leadership at regular radiology meetings at Nambour General Hospital.
Dr. Chris Yu
MBBS, FRANZCR
Dr. Chris Yu is a dual qualified radiologist and an accredited consultant in both radiology and nuclear medicine. Following graduation from Sydney University, Dr. Yu completed his radiology training and fellowship at the Royal North Shore Hospital in Sydney.
Dr. Yu’s main interest is in Nuclear Medicine, cross-sectional CT and MRI imaging, particularly in musculoskeletal and oncology imaging. Currently, Dr. Yu is a staff specialist at the Princess Alexandra Hospital and is actively involved in registrar training and medical student teaching.