Tag: lung imaging

When Chest CT Needs a Functional Layer

Posted on by Partner Content

Regional lung function is emerging as an important factor in thoracic imaging. While chest CT is central to evaluating lung disease, anatomy (structure) alone does not always explain the full clinical challenge. Fortunately, a new generation of CT-based software tools brings regional lung function into the workflow radiologists use every day – chest CT.

Patients with dyspnea, COPD, emphysema, interstitial lung disease, or pulmonary vascular questions can often have symptoms that are difficult to reconcile with structural findings alone.

Radiologists and clinicians assemble the broader clinical picture from multiple sources: CT findings, pulmonary function tests, and nuclear medicine ventilation/perfusion (V/Q) exams. 

  • Each offers useful information, but each has limits. Pulmonary function tests provide global measures rather than regional detail, while V/Q imaging depends on radiotracer availability, department hours, and nuclear medicine resources.

One example of an emerging technology that provides radiologists with deeper, functional pulmonary detail is CT:VQ from 4DMedical. 

  • CT:VQ, operating in a Software as a Service (SaaS) mode, uses paired inspiratory and expiratory non-contrast chest CT scans to generate regional ventilation and perfusion maps – along with quantitative outputs designed for radiology workflow.

This approach brings functional lung information closer to the CT reading room without requiring injected contrast or radiotracers for the CT:VQ analysis. 

  • It also builds on a modality that is widely available and often operational around the clock.

Adding regional ventilation and perfusion information to CT could help address common thoracic imaging questions…

  • Which regions are ventilating well, and which are not?
  • Is perfusion preserved in areas that look abnormal on CT?
  • Do symptoms align with regional functional impairment?
  • Which lung regions may be most important to preserve before intervention?

The non-contrast approach has compelling clinical advantages… 

  • Contrast can trigger renal screening, prior reaction history, IV access challenges, workflow delays, and patient anxiety. 
  • Avoiding contrast can simplify the pathway for many patients.

CT-based functional imaging is not a replacement for legacy lung function assessments. But it brings quantitative tools that can make routine studies more clinically actionable.

The Takeaway

Technology brings radiologists new opportunities. Chest CT can reveal far more than what the lungs look like. With tools such as CT:VQ, CT can show regional patterns of lung ventilation and perfusion – adding functional context to a radiologist’s toolkit.

More information about CT:VQ and non-contrast functional lung imaging is available at ctvq.com.

CT Lung Screening Chats Pay Off

Posted on by Brian Casey

Patients who talked about CT lung cancer screening with their doctors were more likely to actually follow through on getting scanned. That’s according to a study this week in CHEST that offers support for shared decision making – a process that some screening proponents have criticized.

The U.S. continues to see disappointing compliance rates for CT lung cancer screening, over 10 years after the USPSTF recommended the exam.

  • Some lung screening proponents suggest that one barrier to screening is a CMS rule requiring a shared decision-making session between patients and doctors before the first scan is performed – a requirement that’s not in place for any of the other major cancer screening tests.

But the new study indicates that shared decision making could actually work to boost compliance. 

  • Researchers from the Harvey L. Neiman Health Policy Institute led by first author YoonKyung Chung, PhD, examined lung screening compliance rates for 22.6k people who had their first CT exam between 2016 and 2019.

Researchers looked at differences in annual follow-up lung screening rates between people who got shared decision-making sessions and those who didn’t, finding… 

  • Only 11% of study participants had a session before their first scan.
  • One year after the initial scan, those who participated in sessions were 27% more likely to get a follow-up exam.
  • Four years later, the compliance rate rose to 33%. 

If CMS requires shared decision-making sessions for reimbursement, why are they occurring so infrequently? 

  • The authors called this phenomenon “puzzling,” and suggested it’s because CMS is not enforcing the mandate through tools like claims denial. CMS could also boost utilization by providing higher reimbursement for the discussions.

The Takeaway

The new findings suggest that shared decision making should be viewed as an opportunity rather than a barrier to convincing patients of CT lung cancer screening’s value. The results track with other studies showing that a high-touch approach with tools like patient navigators can work.

How COVID Crashed CT Scanners in China

Posted on by Brian Casey

In the early days of the COVID-19 pandemic in China, hospitals were performing so many lung scans of infected patients that CT scanners were crashing. That’s according to an article based on an interview with a Wuhan radiologist that provides a chilling first-hand account of radiology’s role in what’s become the biggest public health crisis of the 21st century.

The interview was originally published in 2022 by the Chinese-language investigative website Caixin and was translated and published this month by U.S. Right to Know, a public health advocacy organization. 

In a sign of the information’s sensitivity, the original publication on Caixin’s website has been deleted, but U.S. Right to Know obtained the document from the US State Department under the Freedom of Information Act. 

Radiologists at a Wuhan hospital noticed how COVID cases began doubling every 3-4 days in early January 2020, the article states, with many patients showing signs of ground-glass opacities on CT lung scans – a telltale sign of COVID infection. But Chinese authorities suppressed news about the rapid spread of the virus, and by January 11 the official estimate was that there were only 41 COVID cases in the entire country.

In reality, COVID cases were growing rapidly. CT machines began crashing in the fourth week of January due to overheating, said the radiologist, who estimated the number of cases in Wuhan at 10,000 by January 21. Hospitals were forced to turn infected patients away, and many people were so sick they were unable to climb onto X-ray tables for exams. Other details included: 

  • Chinese regulatory authorities denied that human-to-human transmission of the SARS CoV-2 virus was occurring even as healthcare workers began falling ill
  • Many workers at Chinese hospitals were discouraged from wearing masks in the pandemic’s early days to maintain the charade that human-to-human contact was not possible – and many ended up contracting the virus
  • Radiologists and other physicians lived in fear of retaliation if they spoke up about the virus’ rapid spread

The Takeaway

The article provides a stunning behind-the-scenes look at the early days of a pandemic that would go on to reshape the world in 2020. What’s more, it demonstrates the vital role of radiology as a front-line service that’s key to the early identification and treatment of disease – even in the face of bureaucratic barriers to delivering quality care.

Developing the Eighth Modality

Posted on by Jake Fishman

Radiology has adopted seven mainstream modalities over its 127 years, and 4DMedical is determined to create the eighth imaging modality with its new XV Scanner.

The XV Scanner would be the first dedicated lung imaging system, giving radiologists four-dimensional and color-coded visibility into patients’ lung airflow and blood flow, and potentially a new way to assess lung diseases. 

  • The XV Scanner integrates fluoroscopy with advanced analytics software, producing qualitative and quantitative 4D lung function metrics 
  • It simultaneously acquires images from different angles, then measures lung tissue motion, and calculates ventilation at each breathing stage and every lung location
  • XV scans take 5 seconds to perform and deliver less radiation than a typical chest X-ray

4DMedical’s XV technology is also backed by a growing number of positive clinical studies, solid post-IPO funding, and an impressive expansion across Australian imaging giant I-Med Radiology’s 250 locations.

Although the XV Scanner hardware is still forthcoming, 4DMedical will initially launch XV software that can be installed on existing fluoroscopy systems (FDA cleared for ventilation, later adding perfusion) and will also support existing CTs in the future. 

  • Software-only might prove to be a logical starting point, providing 4DMedical with a low-friction way to demonstrate XV’s impact on patient care and test whether this impact is great enough to entice imaging departments to add a whole new scanner to their fleets.

The Takeaway

Creating medical imaging’s eighth mainstream modality might be among the most ambitious goals you’ll hear at RSNA 2022, but if the XV Scanner proves to be much better than existing lung imaging techniques, radiology might have to make room for one more.

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