As a consequence, many start-ups are doomed to go to the wall even as they pitch their first venture investor. Others will have an "exit strategy" in place from the off – one that more often than not dictates scratching a living around the zero point long enough to become an acquisition target and part of a bigger whole.

Then there's the select few with true heavyweight credentials. These firms will, by a mixture of good fortune and smart judgement, have the right stuff for sustainable growth and longevity. The list of must-haves varies from case to case but usually entails a laser focus on product innovation, a "what the customer wants the customer gets" mentality, alongside rigid control of operational expenditure.

Two months after the launch of medicalphysicsweb, we've come up with plenty of evidence to suggest that all manner of small companies - the bedrock of technology transfer and innovation - are pushing the envelope of diagnostics and therapeutics in the core disciplines of medical physics. Furthermore, if the number of page views in our Industry News & Analysis channel is anything to go by, editorial coverage of product development in small companies is clearly hitting the mark with our readers.

Make it happen

This level of interest comes as no surprise. After all, today's early-stage start-up project could be tomorrow's blockbuster new product. Among the latest start-up stories attracting reader eyeballs is Proton therapy: think smaller, think cheaper. The commercial opening here is in proton radiation therapy - and more specifically, the high capital outlay ($90–180 m) associated with the particle accelerator. Slashing that outlay is the raison d'être at Still River Systems, a US start-up that reckons it can reduce the size, cost and complexity of the accelerator and make pared-down proton sources that fit within a treatment room available in the next 18 months.

Another US firm that's thinking big by thinking small is Sicel Technologies (see Think small: implantable dosimeters). The company, which is based in Raleigh, NC, has come up with a new take on an old problem: an implantable dosimeter that verifies radiation dose at the site of the tumour or surrounding tissues and communicates data wirelessly to a hand-held reader. Sicel claims its device measures the dose delivered in tissue, including the combined effects of tissue inhomogeneity, organ movement, patient set-up errors and intrafractional movement - all factors that can result in a significant difference between planned versus actual radiation delivery.

While small is generally good in product innovation, so too is safety. A case in point is UK-based Metrasens, which has made patient/technician safety its core competency (see MRI facilities: the starting point is safety). By transferring technology originally developed for submarine detection - the company is a spin-off from international defence research group QinetiQ - Metrasens is busy commercializing a ferromagnetic detection system that will make MRI facilities safer. Called Ferroguard, the ferrous-only metal-detection technology is designed to prevent projectile accidents in MRI facilities, where ferrous objects are attracted at great speed towards the magnet bore.

Still River, Sicel and Metrasens are just three case studies in innovation among many already featured in the Industry News and Research News channels on medicalphysicsweb. The big question for these developers, and the ranks of start-ups like them, is how best to turn potentially game-changing innovation into sustainable profitability and growth. Get that right and the step-function transition to big technology company suddenly starts to look achievable.