VOICE PROSTHESIS

(50-Mark Answer - RGUHS ENT Examination Standard)

1. INTRODUCTION

• First commercially available device: Singer and Blom (1980) - the Blom-Singer Duckbill prosthesis
• First indwelling device: Groningen prosthesis (1984) by Henk Nijdam
• First Provox device: 1990 by Atos Medical (Amsterdam)

2. ANATOMY OF THE PHARYNGOESOPHAGEAL (PE) SEGMENT

• Inferior constrictor muscle
• Cricopharyngeus (upper esophageal sphincter)
• Upper cervical esophagus

3. METHODS OF ALARYNGEAL SPEECH

┌──────────────────────────────────────────────────────────────┐
│           POST-LARYNGECTOMY SPEECH REHABILITATION            │
└──────────────────────────────────────────────┬───────────────┘
                                               │
          ┌────────────────┬───────────────────┤
          │                │                   │
    ┌─────▼──────┐  ┌──────▼──────┐   ┌───────▼────────┐
    │ Esophageal │  │ Electrolarynx│   │ Tracheoesoph.  │
    │  Speech    │  │  (Artificial │   │  Voice Prosth. │
    │            │  │   Larynx)    │   │  ← GOLD STD    │
    └─────┬──────┘  └──────┬───────┘   └───────┬────────┘
          │                │                    │
    40-60%         Rapid acquisition        ~90% success
    success        Robot-like voice         Pulmonary driven
    Short phonation  Monotonous            Natural voice quality
    time (1-2 sec)  One-hand occupied      Long phonation time

4. PRINCIPLE OF VOICE PROSTHESIS

                    ┌──────────────────────┐
    Patient occludes│    STOMA OCCLUSION   │
    stoma manually  │  (thumb/HME filter)  │
    or with HME     └─────────┬────────────┘
                              │ Expiratory airflow
                              ▼
              ┌───────────────────────────────┐
              │       VOICE PROSTHESIS        │
              │  (in TEP tract, posterior      │
              │   tracheal / anterior          │
              │   esophageal wall)             │
              │  ┌──────────────────────────┐  │
              │  │ One-way valve OPENS on  │  │
              │  │ expiratory pressure     │  │
              │  └──────────────────────────┘  │
              └──────────────┬────────────────┘
                             │ Air enters esophagus
                             ▼
              ┌───────────────────────────────┐
              │   PE SEGMENT VIBRATES         │
              │   (neoglottis / pseudo-glottis)│
              └──────────────┬────────────────┘
                             │ Sound produced
                             ▼
              ┌───────────────────────────────┐
              │  VOCAL TRACT ARTICULATION     │
              │  (tongue, lips, palate)       │
              └───────────────────────────────┘
                             │
                             ▼
                    INTELLIGIBLE SPEECH

   At end of expiration: valve CLOSES automatically
   → Prevents esophageal reflux/aspiration of saliva/food

5. TRACHEOESOPHAGEAL PUNCTURE (TEP) - THE PROCEDURE

5a. Types by Timing

         TRACHEOESOPHAGEAL PUNCTURE
                    │
        ┌───────────┴──────────────┐
        │                         │
  PRIMARY TEP                SECONDARY TEP
(at time of TL)          (deferred, weeks/months
        │                  after TL surgery)
        │                         │
  Advantages:              Advantages:
  Single anesthesia         Allows pharyngeal
  Immediate rehab           healing first
  No second surgery         Better patient
  Disadvantages:            selection possible
  Pharyngeal edema          Used if post-op
  may complicate            RT anticipated
  prosthesis fitting

5b. Surgical Technique (Singer-Blom Method)

1. Patient positioned supine, neck slightly extended
2. A #14 red rubber catheter passed from the esophagus via the mouth is palpated in the trachea
3. A 16G needle or trocar is passed through the posterior tracheal wall / anterior esophageal wall at the 12 o'clock position, approximately 5mm below the superior tracheal margin of stoma
4. A guidewire is passed through the needle into the esophagus
5. The puncture is dilated
6. The prosthesis is loaded onto an introducer/dilator and inserted
7. Prosthesis flanges secure it in position

6. TYPES OF VOICE PROSTHESES

Classification

          VOICE PROSTHESES
                 │
    ┌────────────┴───────────────┐
    │                           │
NON-INDWELLING              INDWELLING
(Patient-removable)         (Clinician-changed)
         │                         │
  ─ Blom-Singer Duckbill    ─ Blom-Singer Classic
  ─ Provox NiD              ─ Blom-Singer Advantage
  ─ Nijdam prosthesis        ─ Provox 2
  ─ Patient inserts/         ─ Provox Vega™
    removes daily            ─ Provox Vega™ XtraSeal
  ─ Cheaper, shorter         ─ Provox ActiValve
    device life              ─ Longer device life
  ─ Patient compliance       ─ Changed only by
    required                   clinician
                             ─ 70%+ market share (2024)

6a. Non-Indwelling Prostheses

6b. Indwelling Prostheses

7. VOICE PROSTHESIS IN CROSS-SECTION (Structural Diagram)

    TRACHEAL SIDE                          ESOPHAGEAL SIDE
    (anterior)                               (posterior)
         │                                        │
    ─────┼─────────────────────────────────────────┼─────
         │   ┌──────────────────────────────┐      │
         │   │    PROSTHESIS BODY          │      │
    ─────┼───┤  (silicone cylinder)        ├──────┼─────
         │   │                             │      │
    Tracheal │  ┌──────────┐ lumen ┌──────┐│ Esophageal
    flange   │  │          │───────│ VALVE││ flange
    (keeps   │  └──────────┘       └──────┘│ (retention)
    in place)│                             │
         │   └──────────────────────────────┘      │

    [one-way valve opens →→→ with expiratory pressure]
    [closes ←←← automatically when pressure ceases]

1. Tracheal flange - prevents posterior migration
2. Esophageal flange - prevents anterior displacement
3. Shaft/body - traverses the TEP tract
4. One-way valve - duck-bill or hinge type; opens in one direction only
5. Low-pressure valve - critical - opens at ≤5 cm H₂O pressure

8. PATIENT SELECTION CRITERIA

         CANDIDATE ASSESSMENT FOR VOICE PROSTHESIS
                          │
            ┌─────────────┴──────────────┐
            │                            │
      PREREQUISITES                  EXCLUSIONS
            │                            │
  ✓ Total laryngectomy             ✗ Poor pharyngeal
  ✓ Adequate manual dexterity          function
  ✓ Motivated patient             ✗ Severe GERD
  ✓ Normal swallowing             ✗ Esophageal stricture
  ✓ PE segment functional         ✗ Severe neurologic
  ✓ Air insufflation test             deficit
    positive (±)                  ✗ Active pharyngeal
  ✓ No esophageal stenosis            fistula
  ✓ Adequate tracheal depth       ✗ Poor compliance
  ✓ Psychiatric stability         ✗ Active uncontrolled
                                      pharyngo-cutaneous
                                      fistula

Air Insufflation Test (Pre-operative Assessment)

• A catheter is passed transnasally into the esophagus
• Air is insufflated at 80-100 mL/sec
• Patient attempts phonation
• Positive test: sustained phonation without spasm (predicts good TE voice)
• Spasm present: suggests hypertonic PE segment; may need pharyngeal myotomy or Botox injection

9. PROSTHESIS SIZING AND FITTING

        PROSTHESIS FITTING PROTOCOL
                    │
        ┌───────────▼────────────┐
        │  MEASURE TEP TRACT     │
        │  (using depth gauge)   │
        └───────────┬────────────┘
                    │
        ┌───────────▼────────────┐
        │  SELECT PROSTHESIS     │
        │  LENGTH & DIAMETER     │
        │  (e.g. 8mm, 10mm,      │
        │   12mm lengths;        │
        │   20Fr or 22.5Fr dia.) │
        └───────────┬────────────┘
                    │
        ┌───────────▼────────────┐
        │  INSERT PROSTHESIS     │
        │  (using inserter tool) │
        └───────────┬────────────┘
                    │
        ┌───────────▼────────────┐
        │  VERIFY PLACEMENT      │
        │  (check flanges; both  │
        │  sides correctly seated)│
        └───────────┬────────────┘
                    │
        ┌───────────▼────────────┐
        │  SPEECH THERAPY STARTS │
        │  (Day 1-2 post-fitting) │
        └────────────────────────┘

• Prosthesis length = depth of TEP tract (measured from posterior tracheal to anterior esophageal mucosa)
• Too short: esophageal flange catches; leakage
• Too long: valve does not seat correctly; voice is poor
• Standard lengths: 4 mm to 18 mm (in 2 mm increments)

10. COMPLICATIONS OF VOICE PROSTHESIS AND TEP

10a. Prosthesis-Related Complications

COMPLICATIONS
      │
      ├──── 1. LEAKAGE
      │         ├── Through the prosthesis (valve failure)
      │         │     → Cause: Candida biofilm; valve wear
      │         │     → Management: Replace prosthesis
      │         │       (Provox ActiValve for recurrent Candida)
      │         │
      │         └── Around the prosthesis (periprosthetic)
      │               → Cause: enlarged TEP tract/atrophy
      │               → Mgmt: Downsize → Collagen injection
      │                        → Surgery (closure + re-puncture)
      │
      ├──── 2. PROSTHESIS DISPLACEMENT
      │         ├── Anterior (into trachea) - dislodgement
      │         └── Posterior (into esophagus) - migration
      │               → Risk: Aspiration of prosthesis into airway
      │               → Management: Retrieval endoscopically
      │
      ├──── 3. GRANULATION TISSUE at TEP margin
      │         → Cauterization / excision
      │
      ├──── 4. TEP TRACT INFECTIONS
      │         → Cellulitis, abscess → antibiotics ± drainage
      │
      └──── 5. DIFFICULTY WITH PHONATION
                ├── Hypertonic PE segment
                │     → Pharyngeal myotomy
                │     → Botulinum toxin injection
                └── Hypotonic PE segment
                      → Exercise, insufficient air pressure

10b. TEP Tract Complications

11. THE ROLE OF CANDIDA IN PROSTHESIS FAILURE

• Candida albicans is the primary organism responsible for prosthesis valve failure
• Biofilm formation on silicone surface degrades the valve leaflets
• Results in: leakage through prosthesis, shortened device life
• Prevention/management:
  • Daily prosthesis cleaning (brush provided with each device)
  • Nystatin suspension orally (1-2 mL, rinse and swallow)
  • Amphotericin lozenges
  • Provox ActiValve (silver/gold-impregnated device) - anti-biofilm
  • Probiotics (Lactobacillus) - experimental evidence

12. VOICE OUTCOMES AND QUALITY OF LIFE

• TE voice success rate: ~90% (vs. 40-60% for esophageal speech)
• Typical time to useful speech: 2 weeks post-TEP
• Phonation time: Comparable to normal laryngeal speech (>20 seconds)
• Fundamental frequency: 90-160 Hz (similar to normal)
• Speech intelligibility: Superior to esophageal and electrolarynx speech

• 15 studies, 1085 patients (869 TE voice vs 216 esophageal voice)
• VHI (Voice Handicap Index) significantly better in TEV group (31.93 vs 35.39, p=0.003)
• VrQoL not significantly different (8.27 vs 9.27, p=0.19)
• Conclusion: TEV allows better speech performance but does not necessarily translate to higher quality of life scores

13. HANDS-FREE VALVE (HME - HEAT AND MOISTURE EXCHANGER)

     HME (Heat-Moisture Exchanger) + Automatic Speaking Valve
                          │
     ┌────────────────────▼────────────────────┐
     │  BASEPLATE adhered around stoma         │
     │  ↓                                      │
     │  HME cassette (foam filter inside)      │
     │  ─ Warms/moistens inhaled air           │
     │  ─ Reduces tracheal mucus burden        │
     │  ↓                                      │
     │  AUTOMATIC SPEAKING VALVE               │
     │  ─ Closes automatically during speech  │
     │  ─ Opens for quiet breathing            │
     └─────────────────────────────────────────┘
     Benefits: Hands-free speech; improved pulmonary hygiene;
               reduces chest infections
     Limitations: Not suitable for all patients (e.g., irregular
                   stoma shape, excessive secretions)

14. MANAGEMENT FLOWCHART - PATIENT WITH VOICE PROSTHESIS PROBLEM

       PATIENT PRESENTS WITH VOICE PROSTHESIS PROBLEM
                           │
           ┌───────────────┼──────────────────┐
           │               │                  │
      LEAKAGE           NO VOICE          DISPLACED/
           │               │              MISSING PROSTH
           │               │                  │
    ┌──────┴───────┐  ┌────┴──────┐   ┌───────┴──────┐
    │ THROUGH VP   │  │ PE spasm? │   │ Check inside │
    │ (valve fail) │  │ Tract OK? │   │  trachea or  │
    └──────┬───────┘  └────┬──────┘   │  esophagus  │
           │               │          └───────┬──────┘
     Biofilm/wear   Myotomy/Botox             │
           │         if spasm         Endoscopic retrieval
     Replace VP              │              +
     (try ActiValve    Resize prosth    Re-puncture/
      if recurrent     if too long     refit when stable
      Candida)         or mismatch
           │
    ┌──────┴───────┐
    │ AROUND VP    │
    │ (peri-pros-  │
    │ thetic leak) │
    └──────┬───────┘
       Enlarged tract
           │
    ┌──────┴──────────────────────────────┐
    │ Try smaller prosthesis              │
    │ Collagen/fat injection              │
    │ Temporary closure catheter          │
    │ TEP closure + re-puncture (last)    │
    └─────────────────────────────────────┘

15. VOICE PROSTHESIS REPLACEMENT PROTOCOL

• Leakage through the prosthesis (valve failure)
• Leakage around the prosthesis
• Device fracture
• Patient preference/scheduled replacement

1. Rotate or use a specific inserter-remover tool
2. Existing prosthesis is removed
3. Tract is dilated if needed
4. New prosthesis sized and inserted
5. Confirm flanges are seated
6. Test voice

16. RECENT ADVANCES (RGUHS Current Topics)

17. COMPARISON OF MAJOR PROSTHESES (Exam Table)

18. SUMMARY - KEY POINTS FOR EXAM

┌──────────────────────────────────────────────────────────────┐
│                    VOICE PROSTHESIS - KEY FACTS              │
├──────────────────────────────────────────────────────────────┤
│ 1. GOLD STANDARD for post-laryngectomy voice rehabilitation  │
│ 2. Introduced by SINGER & BLOM in 1980                       │
│ 3. Mechanism: TEP + one-way valve + PE segment vibration     │
│ 4. Types: Non-indwelling (patient-changed) vs Indwelling     │
│    (clinician-changed)                                        │
│ 5. Success rate: ~90%; useful voice in 2 weeks               │
│ 6. Main complication: Candida biofilm → valve failure        │
│ 7. Periprosthetic leak → enlarged tract → downsize/collagen  │
│ 8. Air insufflation test: pre-op assessment of PE segment    │
│ 9. HME: Hands-free speech + pulmonary rehabilitation        │
│ 10. Recent: ActiValve, Provox Vega XtraSeal, SmartInserter  │
└──────────────────────────────────────────────────────────────┘

REFERENCES

1. Cummings Otolaryngology Head and Neck Surgery, 7th Ed. Chapter 111 - "Alaryngeal Voice and Speech Rehabilitation." Elsevier.
2. Scott-Brown's Otorhinolaryngology Head & Neck Surgery, 8th Ed. (8-volume set). CRC Press. ISBN: 9781138094642
3. Dhingra PL & Dhingra S - "Diseases of Ear, Nose and Throat," 8th Ed. - Chapter on Larynx and Voice Rehabilitation.
4. Hazarika P, Nayak DR, Balakrishnan R - "Textbook of Ear, Nose and Throat," Paras Medical.
5. Stell & Maran's Head and Neck Surgery - Chapter on Rehabilitation after Laryngectomy.
6. KJ Lee's Essential Otolaryngology, 11th Ed. ISBN: 9781260122237.
7. Zakir Hussain - ENT Notes for RGUHS (Voice restoration after laryngectomy section).
8. Maniaci A et al. "Voice-Related Quality of Life After Total Laryngectomy: Systematic Review and Meta-Analysis." J Voice. 2024;40(2). [PMID: 34763996]
9. Mayo-Yáñez M et al. "Evidence-Based Recommendations in Primary Tracheoesophageal Puncture for Voice Prosthesis Rehabilitation." Healthcare. 2024;12(6):652. [PMID: 38540616]
10. Atos Medical. "Provox Voice Prostheses - Clinical Literature Review." 2022.
11. Deshpande MS. "Prosthetic voice rehabilitation after total laryngectomy." Indian J Surg Oncol. 2012. [PMC3421009]

RGUHS Exam Tip: For a 50-mark answer, include: Introduction + anatomy (PE segment) + types of alaryngeal speech + principle of TE voice with mechanism diagram + types of prosthesis (non-indwelling vs indwelling with examples) + TEP procedure (primary vs secondary) + patient selection + complications with management flowchart + recent advances + quality of life evidence. Diagrams for the mechanism of speech and TEP anatomy are expected and carry marks.