The human body is the most complex machine you'll ever encounter. Medical physics provides the tools to understand and repair it.
Imagine a world where cancer can be pinpointed and destroyed with pinpoint accuracy, where doctors can watch the brain light up in real time during thought, and where devastating injuries can be repaired with lab-grown tissues. This is the world of medical physics—a specialized and powerful discipline within biomedical engineering that uses the laws of physics to solve some of medicine's most challenging problems.
For undergraduate students, this path represents a unique curriculum that merges a physicist's deep understanding of energy and matter with an engineer's drive to build practical solutions for human health. This article explores how university programs are structuring their curricula to train the next generation of scientists who will use physics not just to see inside the body, but to heal it.
At its core, the medical physics track within a biomedical engineering (BME) specialty is built on a foundation of interdisciplinary science. Students learn to view the human body as a complex system that can be analyzed, measured, and repaired using engineering principles.
Understanding how ionizing radiation interacts with biological tissues, targeting tumors while sparing healthy tissue.
Exploring the physics of non-invasive visualization technologies like MRI, ultrasound, and CT scanning.
Applying mechanical principles to biological systems, from tissue behavior to implant design.
Designing devices that measure physiological signals, from EEG electrodes to blood flow sensors.
Different universities structure this knowledge into specialized courses. The following table outlines examples of core medical physics courses and their focus areas as seen in programs like the University of Wisconsin-Madison 1 .
| Course Topic | Key Focus Areas | Application in Medical Physics |
|---|---|---|
| Radiation Physics & Dosimetry | Interactions of ionizing radiation, dose calculation, safety protocols | Radiotherapy treatment planning, ensuring accurate cancer treatment |
| MRI Physics | Spin physics, pulse sequences, hardware, image artifacts | Operating and improving diagnostic MRI scanners for disease detection |
| Diagnostic Ultrasound | Ultrasonic wave propagation, imaging instrumentation, biological effects | Conducting ultrasound scans for cardiac, obstetric, and abdominal imaging |
| Orthopaedic Biomechanics | Tissue properties, surgical approaches, implant materials | Designing and testing replacement hips, knees, and spinal implants |
While the principles of medical physics can seem abstract, they come to life in the laboratory. A compelling example is the electroencephalography (EEG) experiment, which demonstrates how bioelectric signals from the brain can be captured and analyzed. This experiment is a staple in biomedical engineering physiology courses.
The following steps describe a typical EEG laboratory procedure, adapted from an online learning module developed at the University of California Irvine 8 .
The subject's scalp is cleaned, and a cap containing multiple electrodes is fitted. Electrode gel is applied to ensure a good electrical connection.
The subject performs tasks while EEG is recorded. A classic paradigm involves the oddball task, eliciting the P300 brain potential related to attention.
Electrodes detect tiny voltage fluctuations (microvolts) on the scalp caused by brain activity, which are prone to interference from various sources.
Raw EEG data is processed to remove noise, segmented into epochs, and averaged to reveal event-related potentials (ERPs).
The primary result of this experiment is the clear identification of event-related potentials (ERPs). The following table shows hypothetical data for the amplitude and latency of key ERP components from a group of subjects performing the oddball task.
| ERP Component | Average Amplitude (µV) | Average Latency (ms) | Cognitive Correlation |
|---|---|---|---|
| N100 | -4.5 | 95 | Early auditory processing |
| P200 | 3.2 | 180 | Sensory processing |
| N200 | -5.8 | 240 | Stimulus discrimination |
| P300 | 8.5 | 350 | Attention & context updating |
EEG provides a non-invasive, direct, and real-time measure of brain function with millisecond temporal resolution, allowing researchers and clinicians to diagnose neurological disorders, study cognitive processes, and develop brain-computer interfaces (BCIs).
A significant challenge in medical physics education is demonstrating complex or hazardous concepts safely and effectively. Universities have developed ingenious solutions.
How do you teach students about gamma imaging—a technique that uses radioactive tracers—without any radiation risk? Researchers at University College London (UCL) solved this with "Gamma Anna," an interactive demonstration using analogies 5 .
Generated from a safe chemical reaction
Placed inside a ragdoll, representing tissues that absorb the tracer
Acts as the gamma camera, detecting the heat signal
This demo is cheap, safe, and has been used for everyone from schoolchildren to medical students, improving understanding and engagement.
The work of a medical physics student or researcher relies on a suite of specialized tools and materials. The table below details some key items used in experiments like the EEG lab or in developing new medical technologies.
| Tool/Reagent | Primary Function | Application Example |
|---|---|---|
| Electrode Gel | Ensures strong electrical conductivity between skin and sensor | Applied to EEG and EKG electrodes to capture bioelectric signals from the brain and heart 8 . |
| Conductive Polymers | Used in biosensors and neural interfaces due to their electrical properties | Coating electrodes to improve signal quality or creating flexible sensors for wearable health monitors. |
| Hydrogels | Synthetic, water-swollen polymers that mimic natural tissue | Used in tissue engineering as scaffolds to support cell growth for regenerating muscle or nerve tissue 6 . |
| Gold & Polymer Nanoparticles | Microscopic particles used for targeted drug delivery and imaging | Functionalized with antibodies to attach to cancer cells, allowing for targeted therapy or enhanced imaging contrast 6 . |
| Biocompatible Alloys (e.g., Titanium) | Materials that are non-toxic and not rejected by the body | Used to fabricate permanent medical implants like artificial joints, dental implants, and bone plates . |
The field of medical physics is dynamic, and curricula are evolving to keep pace. Two major trends are shaping its future:
The use of e-learning tools and virtual labs is becoming imperative for this dynamic profession 2 . Interactive simulations allow students to manipulate complex physics models safely and effectively.
For instance, projects like the European Medical Imaging Technology (EMIT) e-modules are used in over 60 countries, providing students with interactive image databases and e-books that would be impossible to replicate with traditional textbooks alone 2 .
Top-tier BME programs strongly encourage undergraduates to engage in hands-on research early in their academic careers 6 . This can take the form of:
In these year-long projects, senior students work in teams to solve a real-world, client-centered biomedical engineering problem, integrating their knowledge of medical physics to design, build, and test a prototype 1 7 .
Different universities offer varied specialized tracks within the broader medical physics and BME landscape. The table below compares the focus of different types of programs.
| Program / Track | Primary Focus | Example Curriculum Content |
|---|---|---|
| BME with Medical Physics Focus | Applying physics principles (radiation, imaging) to diagnose and treat disease | Radiation dosimetry, MRI physics, energy-tissue interactions 1 |
| BME with Biomechanics Track | Applying mechanical principles to biological systems | Orthopaedic biomechanics, implant design, finite element modeling of tissues 1 |
| BME with Bioelectronics Track | Designing electronic devices for medical applications | Bioinstrumentation, biosensors, biopotential amplifiers, electrical safety 1 |
The medical physics pathway within biomedical engineering is more than just a major—it is a conduit for discovery, turning the fundamental laws of physics into tangible hope for patients. From the precise algorithms that sharpen an MRI to the targeted radiation that shrinks a tumor, the work of these scientist-engineers is fundamentally changing medicine. The curriculum is demanding, requiring a firm grasp of multiple scientific disciplines, but it is also immensely rewarding. It prepares students not with a single, static skill set, but with a flexible, analytical mindset capable of solving the health challenges of the future. For those drawn to the interface of physical law and human life, it offers a unique opportunity to leave a lasting mark on the world.