Introduction
Benign paroxysmal positional vertigo (BPPV; also known as otolithiasis) is a common form of vertigo. Most patients with this condition find relief through conservative treatments, such as particle repositioning Epley maneuver. However, others are more difficult to treat.
We report the case of a patient with refractory BPPV who was successfully treated with laser occlusion of the posterior semicircular canal, with no recurrence over five years of follow up.
Case report
A 50-year-old woman was admitted with a four-month history of paroxysmal vertigo. This vertigo had no triggering factors, and was associated with nausea, vomiting and light-headedness. There was no hearing disorder. Episodic vertigo occurred in conjunction with such movements as sitting up, lying down and rolling over. The triggering factors we thought are from epidemiology, such as trauma, hydrolabyrinth. Each episode of vertigo continued for about 10 seconds. A floating sensation while standing worsened when the patient moved her head to the right. The floating sensation is a kind of sensation resulted from both dissymmetry of her vestibular function. She was unable to sleep if she turned her head to the right. Because of the frequency of the vertigo attacks, the patient was in a state of panic; she was terrified to get up, lie down or walk, and could not care for herself. She had visited several hospitals and received various treatments, but results were disappointing. The patient also had a history of hypertension.
General physical examination was unremarkable, with no spontaneous nystagmus. However, the patient initially refused to arise after lying down.
There were no abnormal findings on ear, nose, and throat examination. Results for pure tone audiometry, acoustic impedance and otoacoustic emission testing were normal. Cranial nerve examination was unremarkable, and there were no pathological reflexes. An enhanced magnetic resonance imaging scan of the head showed no abnormal signs. Electronystagmography showed no abnormalities for the saccade test, gaze test, tracking test or caloric test. Dix–Hallpike testing revealed anticlockwise, rotatory nystagmus when the patient's head was turned to the right. The latency of onset was 3 seconds, vertigo continued for about 30 seconds, and multiple repetition of the test resulted in fatigable nystagmus.
The patient was admitted with a diagnosis of posterior canal benign paroxysmal positional vertigo (PC-BPPV). She was prescribed one month of medication, and also underwent the Epley manoeuvre, but her symptoms did not improve. The patient's diagnosis was refined to refractory posterior canal BPPV, and she agreed to undergo laser occlusion of the right posterior semicircular canal.
This procedure was conducted under general anaesthesia. An incision was made immediately behind the right ear. A portion of the mastoid bone was removed to expose the bone surrounding the posterior semicircular canal. A ‘blue line’ was drilled using a diamond burr. A 90º micro hook was used to carefully remove the thinned bone, to produce a 1×2 mm bone window. Using a high power operating microscope, an yttrium aluminium garnet laser was applied through the bone window to partially seal the posterior semicircular canal membrane. The laser working current was 3.0 A, output power was 10 W and acting time was 1 second. Temporalis fascia was used to cover the bone window, and biological glue was applied. No leakage of endolymph fluid was observed.
On the first post-operative day, the patient remained in bed with dizziness. Grade I spontaneous nystagmus was noted, with the fast phase toward the right side. The patient also had panidrosis and slight tinnitus in the right ear, but no hearing loss. Subsequently, her dizziness improved gradually. Seven days post-operatively, the patient was able to walk although she still felt unsteady. Twenty days after the operation, all symptoms had disappeared and the patient was discharged.
One month after discharge, the patient was able to engage in light exercise. Three months post-operatively, the patient was able to lead a normal life. No recurrence was reported over five years of follow up.
Discussion
Benign paroxysmal positional vertigo is a common cause of vertigo, and can be categorised into three types: posterior canal BPPV, lateral canal BPPV and anterior canal BPPV. Of these, posterior canal BPPV is the most common. Because of their complexity, vertigo disorders are often misdiagnosed. The characteristics of posterior canal BPPV are: vertigo when the patient is getting up or lying down; onset in approximately 3–15 seconds; duration of less than 30 seconds; fast phase of the rotatory nystagmus toward the affected ear (when that ear is closest to the ground) during the Dix–Hallpike test; and fatigable nystagmus caused by test repetitions.Reference Garov, Antonian and Sherement1, Reference Nmura2 Our patient had all these symptoms and signs.
The particle repositioning manoeuvre effectively treats most patients with posterior canal BPPV.
• Benign paroxysmal positional vertigo (BPPV; also known as otolithiasis), a common form of vertigo, is generally treated by conservative methods such as particle repositioning
• This paper describes the use of laser occlusion of the posterior semicircular canal to successfully treat a case of refractory BPPV
Surgery is reserved for severe and persistent cases in which particle repositioning is unsuccessful. Posterior semicircular canal occlusion and ampullary nerve section are the two surgical treatment options. The former is simpler and more effective, with fewer complications. Because labyrinthine afferent nerve impulses are not interrupted, patients may experience less post-operative vestibular disorder, quicker balance compensation and no spontaneous nystagmus. Moreover, the operation can be performed under local anaesthesia.Reference Antonelli, Lundy, Kartush, Burgio and Graham3, Reference Antonelli, Bouchard and Kartush4 Ampullary nerve section is reserved for more serious cases, since it is both difficult and risky.Reference Leveque, Labrousse, Seidermann and Chays5
Recent advances in medical laser techniques have made laser occlusion of the posterior semicircular canal more attractive. Antonelli et al. reported that this surgical procedure blocked the membranous semicircular canal more effectively, leading to faster post-operative rehabilitation, and had significantly less vestibular complications, compared with mechanical occlusion.Reference Antonelli, Lundy, Kartush, Burgio and Graham6 Our patient recovered quickly after laser occlusion of the posterior semicircular canal, with satisfactory clinical results and no recurrence over five years of follow up. Therefore, we believe this procedure to be an effective method of treating patients with refractory BPPV, with the potential to reduce complications and recurrence.
