This section describes efficacy outcomes from the published literature that the committee considered as part of the evidence about this procedure. For more detailed information on the evidence, see the interventional procedure overview.
In a case series of 50 patients treated by corticosteroid‑eluting bioabsorbable stent insertion during endoscopic sinus surgery, the mean normalised sino‑nasal outcome test (SNOT)‑22 scores (scale 0 to 5, higher scores indicate worse symptoms) reduced from 2.8 at baseline to 1.0 at 6‑month follow‑up (p<0.0001). The mean Rhinosinusitis Disability Index (scale 0 to 120, higher scores indicate worse symptoms) reduced from 48.5 at baseline to 18.2 at 6‑month follow‑up (p<0.0001).
In a randomised controlled trial (RCT) of 43 patients treated by a corticosteroid‑eluting bioabsorbable stent inserted in the ethmoid sinus on 1 side and a non‑corticosteroid‑eluting bioabsorbable stent inserted in the contralateral side, there was a statistically significant reduction in sinus inflammation, assessed at endoscopy, at days 21 to 45, but not at day 60, in the corticosteroid‑eluting stent group compared with the control stent group. The scores (measured on a 100 mm visual analogue scale) were 29.6 at day 7 and 12.0 at day 60 in the treatment group; and 29.4 and 17.5 respectively in the control group (p=0.09, between group comparison at day 60).
In an RCT of 105 patients treated by a corticosteroid‑releasing bioabsorbable stent inserted in the ethmoid sinus on 1 side and a non‑corticosteroid‑releasing bioabsorbable stent inserted in the contralateral side, frank polyposis (judged by a blinded panel using endoscopy videos) was present in 19% (16 of 85) and 34% (29 of 85) of sinuses respectively at day 30, (p=0.002). In the RCT of 43 patients, there were polypoid mucosal changes in 18% (7 of 38) of sinuses treated by a corticosteroid‑eluting stent and in 37% (14 of 38) of sinuses treated by a control stent at day 60 (p=0.039). In the case series of 50 patients treated by corticosteroid‑eluting bioabsorbable stent insertion during endoscopic sinus surgery, there was polypoid tissue formation at day 30 in 10% (9 of 90) of sinuses and frank polyposis in 2% (2 of 90) of sinuses.
In the RCT of 105 patients, there were significant adhesions in 5% (5 of 104) of sinuses treated by a corticosteroid‑eluting bioabsorbable stent and in 13% (13 of 104) of sinuses treated by a non‑corticosteroid releasing bioabsorbable stent at day 30 (p=0.039). In the RCT of 43 patients, there were significant adhesions in 5% (2 of 38) of sinuses treated by a corticosteroid‑eluting bioabsorbable stent and in 21% (8 of 38) of sinuses treated by a control stent at day 60 (p=0.031). In the case series of 50 patients treated by corticosteroid‑eluting bioabsorbable stent insertion during endoscopic sinus surgery, there were significant adhesions in 1% (1 of 90) of sinuses.
In the case series of 50 patients treated by corticosteroid‑eluting bioabsorbable stent insertion during endoscopic sinus surgery, 1 patient needed surgical revision within 6 months. In the RCT of 105 patients, there was a need (as judged by a blinded panel using endoscopy videos) for postoperative intervention (either surgery to separate an adhesion or oral corticosteroids to resolve recurrent inflammation) in 33% (32 of 96) of sinuses treated by a corticosteroid‑releasing bioabsorbable stent and in 47% (45 of 96) of sinuses treated by a non‑corticosteroid‑releasing bioabsorbable stent at day 30 (p=0.028).
The specialist advisers listed the following key efficacy outcomes: symptomatic improvement; endoscopic improvement of oedema, polyposis and adhesions; long‑term maintenance of sinus patency on clinical examination; the need for postoperative intervention; and the need for oral corticosteroids.