Tech Topic | Vestibular Diagnosis & Rehabilitation | November 2013 Hearing Review

The TRV Chair: Introductory Concepts

By Thomas Richard-Vitton, MD, Michelle Petrak, PhD, and Douglas L. Beck, AuD

The execution of positioning maneuvers with the mechanical assistance of the new TRV Chair makes it possible to rapidly evaluate, diagnose, and treat patients with suspected semi-circular canal (SCC) disorders and abnormalities.

A novel mechanical rotating chair used for sophisticated analysis, diagnosis, and treatment of semi-circular canal (SCC) induced dizziness (ie, benign paroxysmal positional vertigo or BPPV) has been named with respect to the inventor and co-author of this article, Thomas Richard-Vitton. The TRV Chair (Figure 1) allows 360° movement of the patient along the plane of each semicircular canal in tandem with simultaneous analysis of nystagmus via infrared goggles. In this article, we will introduce the preliminary concepts and ideas associated with the TRV Chair.

TRV 1_opt

Figure 1. Patient situated within the TRV Chair with restraints and goggles.

When patients present with, or are suspected of having, BPPV, the clinician often performs the Dix-Hallpike Maneuver (DHM) to evaluate positional nystagmus (Figure 2). Indeed, while the right ear is “down,” the right posterior and left anterior SCCs are evaluated and the converse is true regarding left ear “down.” Unfortunately, the DHM protocol is variable as each clinician performs it more or less aggressively and with variable positioning speed (from upright to supine) and with various degrees of “up” or “down” final positioning. Further, the DHM may be difficult and uncomfortable for many patients as they are physically manipulated by the clinician, which may potentially aggravate pre-existing neck or back discomfort.

TRV2 opt

Figure 2. The Dix-Hallpike Manuever engaged via the TRV Chair.


With the TRV Chair, the DHM is a very different experience for the patient and the clinician. Specifically, the DHM is performed on each side, allowing observation of positional nystagmus due to posterior and/or anterior canal stimulation.

For example, the patient in the TRV Chair starts in the supine position and is quickly rotated 90° to the “left ear down” position, resulting in the head being placed 45° under the horizontal plane (Figure 3). When the left ear is “down,” the SCCs being stimulated are the left posterior and the right anterior. When the right ear is “down,” the right posterior and the left anterior are stimulated.

TRV3 opt

Figure 3. DHM with left ear down. Note vertical canal involvement is characterized by a torsional component demonstrated by fast-phase clockwise motion for the left side down and counterclockwise for the right side down.

On many occasions, there are additional up-beating vertical components from the posterior SCC and down-beating from the anterior SCC.1-4 Regarding involvement of the horizontal canals, the side that needs to be treated is the side with the stronger geotropic (“beating toward the floor”) nystagmus (see Ewald Laws5).

Canal-specific Maneuvers

After positional testing has been completed and the location of the (suspected) calcium carbonate particles has been determined, canal-specific repositioning maneuvers can be performed. Epley or Semont maneuvers are used for posterior canal repositioning. The “Dynamic Barbecue Maneuvers” (DBM, rotation toward the safe side) is recommended for horizontal SCC involvement, and the Lorin Maneuver is recommended for the anterior SCC involvement.

Epley Maneuver. When severe vertigo is apparent during the Dix-Hallpike Maneuver and when a very short latency between the onset of the DHM and nystagmus is apparent, it appears likely the canalith particles are larger/heavier and are moving robustly. In these cases, an Epley Maneuver is performed after the DHM (Figure 4).

TRV4 opt

Figure 4. Epley Maneuver for the left ear.


To facilitate “debris migration,” a session of “decelerations” is employed. Thus, the first step is to initiate two “shocks” against the TRV Chair shock absorbers (a shock is simply a bump against the rubber stopper to attempt to dislodge the otolith particles). After the two shocks, the patient stays in the DHM position with the head 45° down, and after a 1-minute pause, the chair is turned 180° toward the normal side. This positioning places the stoma of the posterior canal toward the floor and permits the particles to migrate through the common crus.

Nystagmus often occurs as the particles migrate into the normal position, similar to the nystagmus observed during the Dix-Hallpike Maneuver. After the nystagmus decreases, two more shocks are initiated. The patient remains in this same position for one additional minute and is then returned to the sitting-up position.

Semont Maneuver. When vertigo is apparent and has a longer latency (perhaps 0.66 seconds), the Semont is the “maneuver of choice” as it adds kinetic energy to the particles and facilitates particulate migration (Figure 5). Like the Epley, the Semont Maneuver is performed after the DHM.

TRV5 opt

Figure 5. Semont Maneuver for left posterior canalithiasis.


Prior to the Semont Maneuver, two successive shocks are made to facilitate displacement of the particles and increase their movement toward the stoma of the posterior semicircular canal. Additionally, a 270° rotation toward the opposite side is initiated with a brisk stop on the TRV Chair shock absorber, to once again facilitate particulate migration through the common crus. The patient is maintained in this position for 2 minutes and is then placed upright.

Often at this time, a very strong down-beating nystagmus is observed with an inconsistent torsional component. This down-beating component may be secondary to a “suction effect” of the anterior ampulla as a clot of particulate matter migrates through the common crus toward the utricle. This late burst of nystagmus has been clinically observed previously, yet its origin remains unknown.

Dynamic Barbecue Maneuver. To evaluate the horizontal SCCs, the patient is placed supine and rotated 90° to the left, and is returned to supine, and then rotated 90° to the right. The Dynamic Barbecue Maneuver (DBM) roll is the traditional procedure for treating horizontal canal BPPV (Figure 6).6 The DBM consists of placing the patient in the supine position and then initiating eight 360° rotations with acceleration during each rotation and then smoothly decelerating. It is good clinical practice to always initiate the DBM toward the stable/healthy ear. For example, given a right ear horizontal SCC problem, rotate toward the left ear.

TRV6 opt

Figure 6. Beginning position for DBM.


The initial eight rotations are followed by a second series of rotations with each series lasting 7 to 10 seconds. In the second set of rotations, we advocate a sudden stop with a brief reverse rotation. The last set of rotations is slower, and when the nose of the patient is 90° toward the normal side, the chair is rotated in the opposite direction and briskly stopped by means of the mechanical lock system to add kinetic energy to the particles to help them migrate toward the stoma of the canal. The ending head position is 45° toward the normal side, placing the stoma of the canal vertical to increase the probability that the particles migrate into the utricle. This position is maintained for 2 minutes (Figure 7). The patient is then placed upright and released.

TRV7 opt

Figure 7. Rotations during the DBM.



The execution of these positional and positioning maneuvers with the mechanical assistance of the TRV Chair makes it possible to rapidly evaluate, diagnose, and treat patients with suspected SCC disorders and abnormalities. Specifically:

  • The incorporation of infrared video goggles provides constant examination and analysis.
  • Maneuvering in the chair avoids triggering cervical proprioceptive actions because the patient is mobilized.
  • The TRV Chair increases the quality of the diagnosis and simplifies the treatment of these patients and is particularly useful for “fragile” patients and those uncomfortable or unable to be traditionally positioned. 

References and Recommended Reading

1. Brandt T. Vertigo. Its Multisensory Syndromes. London: Springer; 2003.

2. Sauvage JP, Chays A, Gentine A. Vertiges positionnels. Rapport de la Société Française d’Oto-rhino-laryngologie et de Chirurgie de la face et du Cou. Paris; 2007.

3. Lee SH, Kim JS. Benign paroxysmal positional vertigo. J Clin Neurol. 2010;6(2):51-63.

4. Bhattacharyya N, Baugh RF, Orvidas L, Barrs D, Bronston LJ, Cass S, Chalian AA, Desmond AL, Earll JM, Fife TD, Fuller DC, Judge Jo, Mann NR, Rosenfeld RM, Schuring LT, Steiner RW, Whitney SL, Haidari J; American Academy of Otolaryngology-Head and Neck Surgery Foundation. Clinical practice guideline: benign paroxysmal positional vertigo. Am Acad Otolaryngol Head Neck Surg. 2008;139(5 Suppl 4):S47-81. Review.

5. Ewald J. Zur Physiologie des labyrinths. IV Mitteilung. Arch F.D. Ges Physiol. 1895;60:492

6. Richard-Vitton T, Seidermann L, Fraget P, Mouillet J, Astier P, Chays A. Benign positional vertigo, an armchair for diagnosis and for treatment: description and significance. Rev Laryngol Otol Rhinol (Bord). 2005;126(4):249-51.

7. Lorin P. Benign paroxysmal positional vertigo of the anterior semicircular canal: clinical aspects and treatment. Rev Laryngol Otol Rhinol (Bord). 2005;126(4):263-6.

8. Richard-Vitton T, Seidermann L, Fraget P, Mouillet J, Astier P, Chays A. Benign positional vertigo, an armchair for diagnosis and for treatment: description and significance. Rev Laryngol Otol Rhinol (Bord). 2005;126(4):249-51. French

9. Richard-Vitton T, Viirre E. Unsteadiness and drunkenness sensations as a new sub-type of BPPV. Rev Laryngol Otol Rhinol (Bord). 2011;132(2):75-80.


Citation for this article: Richard-Vitton T, Petrak M, Beck DL. The TVR chair: Introductory concepts. Hearing Review. 2013;20(12):52-54.