NoSeal Trial: Comparing Sealants Versus No Sealant for Preventing CSF Leak After Endonasal Skull Base Surgery

Study Purpose

Postoperative cerebrospinal fluid (CSF) leak is a significant complication of endoscopic endonasal approaches (EEA) to the skull base. The use of tissue sealants such as fibrin glue (Tisseel) or synthetic agents (PEI/PEG) is widespread in surgical practice, however, recent high-quality evidence challenges their clinical benefit and cost-effectiveness. This study aims to investigate whether the routine use of sealants in patient with peri-operatively assessed low CSF leak risk, significantly improves outcomes over no sealant use, to guide more cost- effective, evidence-based closure strategies. To the best of our knowledge, the present study is the first randomized clinical trial to evaluate the necessity and comparative effectiveness of fibrin and synthetic sealants versus no sealant in preventing postoperative CSF leaks following endoscopic endonasal surgery in low-post operative CSF leak risk patients.

Recruitment Criteria

Accepts Healthy Volunteers

Healthy volunteers are participants who do not have a disease or condition, or related conditions or symptoms

No
Study Type

An interventional clinical study is where participants are assigned to receive one or more interventions (or no intervention) so that researchers can evaluate the effects of the interventions on biomedical or health-related outcomes.


An observational clinical study is where participants identified as belonging to study groups are assessed for biomedical or health outcomes.


Searching Both is inclusive of interventional and observational studies.

Interventional
Eligible Ages 18 Years and Over
Gender All
More Inclusion & Exclusion Criteria

Inclusion Criteria:

  • - Age ≥ 18 years.
  • - Scheduled for endoscopic endonasal surgery involving standard skull base reconstruction.
  • - Informed written consent obtained prior to enrollment.
  • - Hemodynamic and electrolyte stability before surgery.
  • - Procedure expected to be completed without use of high-flow intraoperative CSF diversion techniques.

Exclusion Criteria:

  • - Revision surgery or extended endoscopic approaches requiring complex reconstruction (e.g., clival or cribriform defects) - Tumors requiring complex sella reconstruction from the start.
  • - Preoperative hydrocephalus.
  • - Known allergy to fibrin-based or synthetic sealant components.
  • - Active sinus infection or systemic inflammatory disease.
  • - Prior radiotherapy to the sellar or parasellar region.
  • - Uncontrolled diabetes mellitus (HbA1c > 7.0%) - Participation in another interventional trial that may influence wound healing or CSF assessment.
- Radiologic signs of chronic intracranial hypertension or hypotension

Trial Details

Trial ID:

This trial id was obtained from ClinicalTrials.gov, a service of the U.S. National Institutes of Health, providing information on publicly and privately supported clinical studies of human participants with locations in all 50 States and in 196 countries.

NCT07216157
Phase

Phase 1: Studies that emphasize safety and how the drug is metabolized and excreted in humans.

Phase 2: Studies that gather preliminary data on effectiveness (whether the drug works in people who have a certain disease or condition) and additional safety data.

Phase 3: Studies that gather more information about safety and effectiveness by studying different populations and different dosages and by using the drug in combination with other drugs.

Phase 4: Studies occurring after FDA has approved a drug for marketing, efficacy, or optimal use.

N/A
Lead Sponsor

The sponsor is the organization or person who oversees the clinical study and is responsible for analyzing the study data.

Maria Sklodowska-Curie National Research Institute of Oncology
Principal Investigator

The person who is responsible for the scientific and technical direction of the entire clinical study.

N/A
Principal Investigator Affiliation N/A
Agency Class

Category of organization(s) involved as sponsor (and collaborator) supporting the trial.

Other
Overall Status Recruiting
Countries Poland
Conditions

The disease, disorder, syndrome, illness, or injury that is being studied.

CerebroSpinal Fluid (CSF) Leak
Additional Details

Introduction Postoperative cerebrospinal fluid (CSF) leak is a significant complication of endoscopic endonasal approaches (EEA) to the skull base. The use of tissue sealants such as fibrin glue (Tisseel) or synthetic agents (PEI/PEG) is widespread in surgical practice, however, recent high-quality evidence challenges their clinical benefit and cost-effectiveness. This study aims to investigate whether the routine use of sealants in patient with peri-operatively assessed low CSF leak risk, significantly improves outcomes over no sealant use, to guide more cost- effective, evidence-based closure strategies. To the best of our knowledge, the present study is the first randomized clinical trial to evaluate the necessity and comparative effectiveness of fibrin and synthetic sealants versus no sealant in preventing postoperative CSF leaks following endoscopic endonasal surgery in low-post operative CSF leak risk patients. Materials and Methods This is a prospective, randomized, controlled, single-center clinical trial conducted at the Maria Skłodowska-Curie National Research Institute of Oncology in Warsaw, Poland. Adult patients scheduled for endoscopic endonasal surgery (EES) will first undergo screening based on medical history and detailed radiological evaluation. Those who meet all predefined inclusion and exclusion criteria will be enrolled and randomized preoperatively using a computer-generated allocation sequence into one of three treatment arms:

  • (1) no sealant (standard multilayer closure), (2) fibrin glue application (Tisseel®), or (3) synthetic polyethylene glycol-based sealant (Adherus®).
Following randomization, surgery will be performed in accordance with the assigned intervention. The primary endpoint is the incidence of postoperative cerebrospinal fluid (CSF) leak within 3 months. Secondary outcomes include endoscopic evaluation of mucosal healing at 6 weeks and 3 months, postoperative complication rates (e.g., meningitis, pneumocephalus), reoperation rate, patient-reported quality of life, and a cost-effectiveness analysis comparing sealant use to standard closure. The study is designed and will be reported in accordance with the SPIRIT 2025 (Standard Protocol Items: Recommendations for Interventional Trials) guidelines to ensure methodological transparency and reproducibility. Results Initial enrollment includes a target of 225 patients (75 per arm). Interim data analysis focuses on early healing parameters, safety profiles, and cost metrics. Hypothesis testing will determine if either sealant significantly reduces CSF leak rates compared to no sealant and whether the marginal benefit justifies routine use in all patients. Exploratory endpoints include biomaterial handling characteristics and surgeon-reported usability. Conclusion The NoSeal Trial addresses a critical gap in evidence regarding the necessity and comparative performance of sealants in skull base reconstruction. By evaluating both clinical outcomes and economic impact, the study seeks to optimize surgical protocols and improve the safety and efficiency of endonasal neurosurgical procedures.

Arms & Interventions

Arms

Experimental: No Sealant - Standard Multilayer Closure

Patients in this arm will receive standard multilayer closure without the use of any sealant. Closure will involve mucosal flap repositioning and hemostatic agents (e.g., Surgicel®, TachoSil®), in accordance with standard endoscopic skull base reconstruction techniques.

Experimental: Fibrin Glue - Tisseel® Application

Patients will undergo standard multilayer closure followed by application of fibrin sealant (Tisseel®). This arm evaluates the effect of biologic tissue glue in preventing postoperative CSF leaks and promoting wound healing following endonasal skull base surgery.

Experimental: Synthetic Sealant - Adherus® Application

This arm involves standard multilayer closure followed by the application of a two-component synthetic polyethylene glycol-based sealant (Adherus®). The objective is to evaluate the synthetic agent's efficacy and cost-effectiveness in reducing postoperative CSF leaks.

Interventions

Procedure: - Standard multilayer closure without sealant

Patients will undergo standard skull base reconstruction using mucosal flap repositioning and absorbable hemostatics (e.g., Surgicel®, TachoSil®), without application of any fibrin or synthetic sealant. This serves as the control group for comparison with sealant-assisted closures.

Device: - Fibrin sealant application

Following standard multilayer closure, patients in this group will receive topical application of a fibrin-based biological sealant (Tisseel®). The intervention aims to assess its effectiveness in preventing postoperative cerebrospinal fluid (CSF) leak and promoting mucosal healing after endoscopic endonasal skull base surgery.

Device: - Synthetic polyethylene glycol-based sealant

After standard multilayer closure, a synthetic two-component sealant (Adherus®, composed of polyethylene glycol and polyethylenimine) will be applied to reinforce the reconstruction site. This group is used to evaluate the efficacy and safety of synthetic sealant in preventing CSF leaks and supporting wound healing.

Contact a Trial Team

If you are interested in learning more about this trial, find the trial site nearest to your location and contact the site coordinator via email or phone. We also strongly recommend that you consult with your healthcare provider about the trials that may interest you and refer to our terms of service below.

International Sites

Warsaw 756135, Poland

Status

Recruiting

Address

Maria Sklodowska-Curie Institute - Oncology Center

Warsaw 756135, ,

Stay Informed & Connected