Radiology with a Dose of Insight

Contrast Media Safety: What Radiologists and Radiographers Need to Know

With Dr. Ranchod, diagnostic and interventional radiologist. This episode is for radiologists, radiographers, and anyone involved in requesting or performing imaging studies who want to replace outdated clinical dogma with evidence-based practice. Dr. Ranchod, a South African diagnostic and interventional radiologist with over 25 years of experience, systematically dismantles the most persistent misconceptions in contrast media safety, including the widely held but scientifically unfounded belief that iodine allergy is a real clinical entity. Dr. Ranchod explains why there is no such thing as iodine allergy: iodine is a trace element essential for thyroid function and encountered daily in iodized salt, not an allergen. Adverse reactions to contrast media are caused by the artificial chemical compounds added to the tri-iodinated benzene ring, not iodine itself. The episode unpacks the difference between allergic-like (anaphylactoid) reactions and physiological reactions, and classifies them as mild, moderate, and severe with clear management pathways including antihistamines, bronchodilators, epinephrine, and full resuscitation protocols. The discussion covers CT radiation dose safety and the use of iterative reconstruction algorithms and weight-based protocols to keep dose as low as reasonably achievable (ALARA), including paediatric-specific safeguards. MRI safety is addressed in depth: metallic projectile hazards, pacemaker and aneurysm clip contraindications, MRI-conditional devices, and the critical recommendation to perform a chest X-ray before emergency MRI in stroke patients who cannot provide a history. Gadolinium-based contrast agents are examined through the lens of nephrogenic systemic fibrosis (NSF): why it only emerged when double and triple doses were given to patients with peripheral vascular disease and low GFR, why linear agents carry the association, and what gadolinium retention in brain, bone, and heart currently means clinically (no proven harm, but caution in paediatrics). The episode also addresses iodinated contrast in pregnancy, porphyria, and asthma, the fish and shellfish allergy myth, and when premedication with steroids is genuinely warranted versus defensive medicine. A national cumulative radiation dose registry for South Africa is proposed as a key patient safety reform.

Balancing Diagnostic Precision and Renal Safety

Radiology & nephrology: evolving partnership in contrast decisions. In this episode of Radiology with a Dose of Insight, we explore one of the most nuanced and often debated areas in modern imaging: the use of contrast agents in patients at risk of kidney injury. Joined by Dr Ashesh Ranchod and Dr Muhammed Hassen, we unpack the evolving relationship between radiologists and nephrologists — from historical caution and “contrast hysteria” to a more collaborative, evidence-based approach. Through real-world scenarios, including high-stakes emergency decisions, we examine the balance between diagnostic urgency and renal safety. The conversation dives into the shift from Contrast-Induced Nephropathy (CIN) to Post-Contrast Acute Kidney Injury (PC-AKI), the true mechanisms of kidney injury, and how often contrast is wrongly blamed. We also tackle the clinical “gray zone” — patients with borderline renal function — where decision-making becomes less about guidelines and more about judgment, communication, and shared responsibility. Read more on the PRESERVE trial [https://pubmed.ncbi.nlm.nih.gov/23660180/]

The Invisible Revealed: Iodine and the Birth of Clearer Medicine

Why Radiology's most powerful tool isn't the scanner - it's the element inside it. In this episode, we journey through one of medicine’s most dramatic transformations: how a single element turned blurry shadows into lifesaving clarity. From Röntgen’s eerie glowing screen in 1895 to the high-stakes, trial-and-error era of early contrast experiments, we trace the desperate quest to make the invisible visible. Enter iodine — small, mighty, and scientifically elegant. We’re joined again by Dr Ashesh Ranchod, who brings his trademark clarity to the chemistry, physics, and sheer audacity behind iodine’s rise in imaging. Together, we unpack the early toxic formulations, the breakthrough of tri-iodinated benzene rings, the 1950s game-changer Hypaque, and the evolution toward modern non-ionic contrast that revolutionised both CT and vascular imaging. If you’ve ever wondered how radiology moved from murky guesses to precise, targeted diagnosis — this is the story. Bold science. Brave pioneers. And one element that changed everything.

125 Years of Radiology

Paying Homage to the Pioneers. Step inside the story of how radiology taught the world to see the unseen. Host Dr. Mantha Makume chats with Dr. Ashesh Ranchod, one of South Africa’s leading radiologists, to trace the fascinating evolution of medical imaging — from Wilhelm Röntgen’s mysterious “X-rays” to modern AI-powered scans. This episode explores the science, the pioneers, and the daring discoveries that revolutionised how we diagnose and treat disease.