Functional Voice Restoration After Laryngeal Transplantation: A Multidisciplinary Protocol and Longitudinal Outcomes

Area of Science:

• Otolaryngology
• Regenerative Medicine
• Speech-Language Pathology

Background:

• Laryngeal transplantation aims to restore vocal function but lacks standardized voice rehabilitation protocols.
• Existing research focuses on surgical aspects and immunosuppression, with limited guidance on postoperative phonatory recovery.
• Current rehabilitation strategies are often ad hoc, lacking consensus on timing and methods.

Purpose of the Study:

• To establish and evaluate a multidisciplinary, protocolized pathway for voice rehabilitation following laryngeal transplantation.
• To address the gap in standardized protocols for functional recovery after laryngeal transplant.
• To guide evidence-based rehabilitation for institutions performing laryngeal transplantation.

Main Methods:

• Four male laryngeal/hypopharyngeal cancer transplant recipients underwent regular subjective (GRBAS) and objective (acoustic analysis, laryngoscopy) assessments.
• Personalized, weekly speech therapy was provided, with evolving protocols including conventional training and intensive neuromuscular reinnervation strategies.
• Assessments were conducted at 1, 3, 6, and 8 months post-surgery.

Main Results:

• Patients showed progressive improvement in voice quality, with decreased hoarseness, breathiness, and asthenia.
• Maximum Phonation Time (MPT) increased significantly, from an average of 1.8s at 1 month to over 10s in one patient by 8 months.
• Laryngeal sensory function gradually re-established by 3 months, with compensatory ventricular band vibration appearing by 8 months with voice training.

Conclusions:

• A standardized evaluation and individualized training protocol, anchored to neuromuscular reinnervation milestones, effectively restores vocal function after laryngeal transplantation.
• The protocol provides evidence-based timelines and biomarkers, adaptable for various clinical scenarios and applicable to other neurogenic voice disorders.
• Early sensorimotor retraining and monitoring compensatory strategies are crucial for optimizing voice restoration in laryngeal transplant recipients.