Development and In Vivo Evaluation of a Novel Bioabsorbable Polylactic Acid Middle Ear Ventilation Tube

Area of Science:

• Biomaterials Science
• Otolaryngology
• Medical Device Engineering

Background:

• Otitis media with effusion (OME) is a common cause of hearing loss in children, often treated with non-absorbable ventilation tubes requiring removal surgery.
• Bioabsorbable polylactic acid (PLA) presents a biocompatible alternative with tunable degradation for middle-ear implants.
• This study focused on developing and evaluating a novel PLA-based middle-ear ventilation tube.

Purpose of the Study:

• To design and fabricate a novel bioabsorbable polylactic acid (PLA) middle-ear ventilation tube.
• To comprehensively evaluate the biocompatibility, safety, and degradation characteristics of the developed PLA tube.
• To assess the potential of the PLA tube as an alternative to conventional non-absorbable middle-ear ventilation devices.

Main Methods:

• PLA tubes were designed and fabricated, mirroring commercial models.
• In vitro biocompatibility was assessed per ISO 10993 standards.
• In vivo evaluation in a guinea pig model included otoscopy, auditory brainstem response (ABR) testing, micro-CT, and histology.

Main Results:

• Successfully fabricated PLA tubes matched commercial dimensions and demonstrated in vitro biocompatibility.
• In vivo studies showed stable PLA segments with minimal inflammation and no adverse effects on hearing (ABR).
• Micro-CT and histological analyses confirmed tube integrity, initial degradation signs over 9 months, and a favorable tissue response.

Conclusions:

• The novel PLA middle-ear ventilation tube is a promising alternative to non-absorbable tubes for OME treatment.
• The tube exhibits excellent biocompatibility, preserves hearing function, and possesses a controlled degradation profile.
• Preclinical data support further clinical trials to establish safety and efficacy in patients.