Industry News

Photon-counting CT enables lower contrast media for aortic imaging

Photon-counting detector computed tomography (CT) reduces the amount of contrast needed for CT angiography (CTA) while maintaining image quality, according to a new study published in Radiology: Cardiothoracic Imaging, a journal of the Radiological Society of North America (RSNA).

The portion of the aorta that passes through the chest and abdomen is prone to aneurysms. Risk increases with age. Doctors use CTA with contrast media to examine this region of the artery. While the iodinated contrast media used in these exams is considered very safe, there is a higher risk of adverse reactions in patients with kidney disease, or nephropathy.

“Many patients undergoing CTA of the aorta are elderly, and some may suffer from a certain degree of nephropathy,” said senior author Hatem Alkadhi from the Department of Diagnostic and Interventional Radiology at University Hospital Zürich in Zürich, Switzerland. “Thus, they might be at risk for a further reduction of their kidney function due to contrast media administration.”

Using less contrast media is also good for the environment, as iodine breakdown products have harmful environmental effects. In addition, the supply of contrast media has suffered from shortages due to COVID-19-related disruptions in the pharmaceutical supply chain.

Photon-counting detector CT is a new technology that can acquire high-quality images at lower contrast media volume than conventional CT scanners that rely on energy-integrating detectors. It also offers diagnostic quality images at lower radiation dose than those of conventional CT.

Alkadhi and University Hospital

Zurich colleague Kai Higashigaito led a study that looked at a low-volume contrast media protocol with photoncounting detector CT for CTA of the aorta in the chest and abdomen.

The study included 100 people, mean age 75. Patients underwent CTA with photon-counting detector CT of the aorta in the chest and abdomen. The patients had received a previous CTA with conventional CT at equal radiation doses.

Photon-counting CT had a higher contrast-to-noise ratio, a key measure of image quality, which translates to a lowvolume contrast media protocol. Contrast media volume was reduced by 25%.

Two independent readers rated the image quality of photon-counting CT as higher than that of conventional CT at an equal radiation dose.

“We showed that the improved image quality of CTA with photon-counting detector CT systems can be used to reduce the amount of administered contrast media to the patients, without reducing the diagnostic yield of the examination,” Alkadhi said. “Image quality remained at the same level as that of previous CT angiography examinations in the same patients using a conventional CT, despite the fact that we reduced the contrast media volume.”

ESVS AAA guidelines alert recommends “enhanced surveillance” in patients treated with Nellix device In a newly released “focused update” to their 2019 recommendations, the European Society for Vascular Surgery (ESVS) abdominal aortic aneurysm (AAA) guidelines writing committee has published advice on the surveillance and management of patients treated with the Nellix endovascular aneurysm sealing (EVAS) system (Endologix).

Delcath Systems announces updated results from CHOPIN phase 1b trial

Delcath Systems has shared in a press release the publication of updated results from the CHOPIN phase 1b trial conducted at Leiden University Medical Center (Leiden, The Netherlands) on the use of the Delcath Chemosat hepatic delivery system with melphalan (Chemosat) in combination with the immune checkpoint inhibitors (ICI) ipilimumab and nivolumab to treat patients with metastatic uveal melanoma with liver metastases.

The publication is titled ‘Combining melphalan percutaneous hepatic perfusion with ipilimumab plus nivolumab in advanced uveal melanoma: First safety and efficacy data from the phase 1b part of the CHOPIN trial’ and was published in CardioVascular Interventional Radiology (CVIR).

The goal of the CHOPIN trial is to study the safety and potential synergistic effects of systemic ICI therapy ipilimumab plus nivolumab (IPI+NIVO) when combined with Delcath’s proprietary liver-targeted percutaneous hepatic perfusion (PHP) treatment in metastatic uveal melanoma patients. The phase 1b portion of the trial enrolled seven patients, each of whom were treated with two courses of PHP (melphalan 3mg/kg, max. 220 mg per cycle) combined with four courses IPI+NIVO escalating the dosing from 1mg/kg each IPI+NIVO (cohort 1) to IPI 1mg/kg+NIVO 3mg/kg (cohort 2).

via mobile application. We have been using the Viz software for the last several months and have seen improvements in patient care across our institution,” said Philip Batista (Cooper University Health Care, Camden, USA).

Viz.ai claims that the Viz Vascular Suite uses AI to automatically analyse an array of imaging modalities, including computerised tomography (CT), electrocardiogram (ECG), and more for suspected vascular diseases. If a suspected pathology is found, the app automatically alerts and displays high-fidelity patient scans on providers’ mobile devices. Clinicians can use Viz Vascular Suite to remotely coordinate vascular pathology care within a hospital system’s hub and spoke network and enable synchronous,communication among specialists.

Cardiovascular Systems enrols first patient in Japan for KAIZEN clinical study

Cardiovascular Systems Inc (CSI) recently announced initiation of the KAIZEN clinical study of its Diamondback 360 peripheral orbital atherectomy system (OAS) to treat calcified plaque in patients with peripheral arterial disease (PAD).

The first KAIZEN patient was enrolled by Tatsuya Nakama at Tokyo

The committee advises that all patients in whom a Nellix device has been implanted “should be identified, properly informed and enrolled in enhanced surveillance.” If device failure is detected, it states that “early elective device explant should be considered in surgically fit patients”.

The alert, authored by Jon Boyle (Cambridge University Hospitals NHS Trust and University of Cambridge, Cambridge, UK) et al, was published online ahead of print in the European Journal of Vascular and Endovascular Surgery (EJVES).

Boyle and colleagues note that they performed a scoping review of risk for late serious aortic-related adverse events in patients treated with EVAS for AAA based on a literature search in PubMed up to 7 December 2022. Following synthesis of the available evidence, the writing committee agreed on recommendations graded according to the European Society of Cardiology (ESC) grading system.

“EVAS has a very high incidence of late endograft migration resulting in proximal type 1 endoleak with risk of rupture, requiring open conversion with device implant,” the authors write, detailing their key finding from the review. They add that the reported mortality for elective explantation varies between 0% and 14%, while acute conversion for rupture has a “very dismal prognosis” with 67–75% mortality.

The determination of a safe and effective dose was a primary goal of the phase 1b portion of the CHOPIN trial. Grade 1/2 adverse events were seen in all patients and 71.4% experienced grade 3/4 toxicities. In this phase 1b dose-escalation study combining M-PHP with IPI+NIVO, the safe treatment dose was established at IPI 1mg/kg and NIVO 3mg/kg. The phase 2 part of the CHOPIN study will provide more information on both hepatic and systemic toxicity associated with the combination therapy.

The rationale for combining ICI therapy with M-PHP in metastatic uveal melanoma is based on both uveal melanoma’s specific characteristics and the unique immunomodulatory role of the liver.

Viz.ai launches AI-powered

Viz Vascular Suite

Viz.ai has announced the launch of Viz Vascular Suite—artificial intelligence (AI)-powered software enabling vascular care teams to automatically detect and triage care for suspected pulmonary embolism, right heart strain, aortic dissection, and abdominal aortic aneurysm (AAA). The company submitted a new 510(k) application to the US Food and Drug Administration (FDA) for the AAA algorithm, a press release notes.

“When Viz identifies an abnormal scan, it quickly notifies the appropriate specialists regardless of their location, facilitating seamless communication

Bay Urayasu Ichikawa Medical Center (Urayasu, Japan). Nakama said: “The Diamondback 360 peripheral OAS offered both effective treatment and ease of use. I observed significant vessel compliance change, permitting satisfactory balloon expansion at low pressure.”

CSI notes that the Diamondback 360 peripheral OAS is a minimally invasive, single-use, catheter-based device designed to differentiate between diseased plaque and healthy arterial tissue. The OAS orbiting crown reduces and modifies calcified plaque while preserving the healthy vessel wall to restore blood flow, the company claims.

KAIZEN is a prospective, singlearm, multicentre study led by Hiroyoshi Yokoi (Fukuoka Sanno Hospital, Fukuoka, Japan), and is designed to evaluate the safety and efficacy of CSI’s Diamondback 360 peripheral OAS in the treatment of de novo symptomatic calcified occlusive atherosclerotic lesions in the superficial femoral artery and/or popliteal artery. According to CSI, OAS has demonstrated safety and efficacy in the US population and this study is designed to confirm this in Japan.