A prospective study has established the safety of venous sinus stenting (VSS) using a novel device in idiopathic intracranial hypertension (IIH) patients who have failed standard medical therapy, as well as suggesting the potential efficacy of this approach.
The RIVER study—from which one-year data were recently published in the Journal of NeuroInterventional Surgery (JNIS)—was performed in order to obtain humanitarian device exemption approval from the US Food and Drug Administration (FDA) for the River stent (Serenity Medical). Writing in JNIS, principal investigator Athos Patsalides (North Shore University Hospital, Manhasset, USA) and colleagues describe this device as “the first stent specifically designed for intracranial venous sinuses”.
“The River stent significantly enhances the treatment of patients suffering from debilitating symptoms of IIH,” Patsalides told NeuroNews. “It provides several advantages over traditional stents, including being the first stent specifically created for patients with IIH, and tailored to the anatomy and function of the cerebral venous system.
“For over 15 years, I have recognised that patients suffering from cerebral venous disorders, such as IIH and pulsatile tinnitus, are often underdiagnosed and treated with suboptimal devices. In the next decade, we will be able to diagnose and manage various conditions using stents and other endovascular implants designed explicitly for the cerebral venous system. The findings from the RIVER study will drive further advancements in the evolving field of cerebral venous disorders and significantly improve patient care.”
Via a prospective, multicentre, single-arm, open-label trial, Patsalides et al enrolled 39 participants across five US centres in order to evaluate the River stent among patients with a clinical diagnosis of IIH who had severe headaches or visual field loss, and in whom conventional medical therapy had been unsuccessful.
Their primary safety endpoint was the one-year rate of major adverse events when compared to historical controls involving cerebrospinal fluid (CSF) shunting, while their primary endpoint in terms of efficacy-related benefits was a composite of clinical improvement and absence of VSS at one year. Secondary endpoints in the RIVER study included improvements in terms of pulsatile tinnitus, visual symptoms, quality of life (QoL) scores, and medication usage.
The authors ultimately report that, in the study, all procedures were technically successful. There was, however, one serious adverse event—a gastrointestinal haemorrhage observed at two months following the procedure while the patient in question was still on dual antiplatelet therapy.
RIVER’s primary safety endpoint was met, with Patsalides et al observing a 5.4% rate of major adverse events with the novel stent device compared to 51.7% in patients who received CSF shunts. The trial’s primary efficacy endpoint was achieved in 60% of trial participants too, with additional improvements also being seen regarding opening CSF pressure, headaches, papilloedema, pulsatile tinnitus, visual symptoms and QoL scores.
Post-hoc analyses relayed by the authors in JNIS suggest that enrolled patients with minimal or absent papilloedema at baseline demonstrated similar levels of clinical improvement versus those who had baseline papilloedema—in terms of headaches, pulsatile tinnitus, and QoL.
These findings lead Patsalides et al to conclude that one-year results from the RIVER study “establish safety and suggest efficacy” with VSS in IIH patients who have failed medical therapy.
“We are highly encouraged by the promising results of this first-of-its-kind study with a stent specifically designed for intracranial venous sinuses,” commented Adnan Siddiqui (Jacobs School of Medicine and Biomedical Sciences, Buffalo, USA), senior author on the paper. “Stents that are currently used in venous sinus stenting were not specifically developed for this purpose. As a dedicated venous device, the length, diameter, radial force and flexibility of the River stent are optimised for the structure and unique mechanical properties of the area we are addressing. We are hopeful that it will offer the opportunity to benefit patients whose lives are disrupted by IIH and who have no options for treatment.”
