Botulinum toxin treatment for essential palatal tremors presenting with nasal clicks instead of pulsatile tinnitus: a case report
© The Author(s). 2016
Received: 30 August 2016
Accepted: 1 November 2016
Published: 22 November 2016
In this study, we report a rare case of an adult patient with essential palatal tremors (EPT) presenting as nasal clicks, instead of otic clicks or objective pulsatile tinnitus in common EPT.
Nasal endoscopic examination and EMG recordings of the soft palate muscles were performed to confirm the source of the clicks. Initial treatment with lidocaine provided symptomatic relief for four hours. The patient was then treated with four simultaneous injections of 12.5 U of botulinum toxin in four different sites of the soft palate. Palatal tremors and clicks completely disappeared within three months of treatment.
To our knowledge, this is the first case of EPT that presented with nasal clicks. We recommend that otolaryngologists should expect this rare occurrence in the clinical setting, and handle patients presenting with such symptoms with care and compassion in order not to worsen their psychological status.
KeywordsCase report Palatal tremors Botulinum toxin Inferior olive Pulsatile tinnitus Electromyography
Palatal tremor i.s a rare movement disorder characterized by continuous rhythmic jerks of the soft palate that are often perceived as tinnitus . Palatal tremors are classified as symptomatic palatal tremors (SPTs) and essential palatal tremors (EPTs). SPTs mainly present with neurological deficits such as dysarthria, nystagmus and ataxia. Abnormalities in the function of the nucleus dentatus, nucleus ruber and/or inferior olivary complex are known to contribute to the pathophysiology of SPT [2, 3]. SPTs rarely present with ear clicks and palatal movements, while EPTs almost exclusively present with ear clicks and palatal movements. Excessive contraction of the tensor veli palatini (TVP) muscle, which is innervated by the trigeminal nerve, is thought to be the cause of EPTs. According to the diagnostic criteria proposed by Deuschl et a1. [3, 4], no intracranial pathology is associated with EPTs. Patients have normal cerebellar function and pendular nystagmus. Furthermore, throat muscle involvement is not expected. In the literature, several cases of EPT associated with psychogenic factors, as well as those of unknown etiology, have been reported [5, 6].
Regardless of etiology, EPTs usually present with objective tinnitus of otic origin or ear clicks. However, EPTs with nasal clicks have hitherto not been reported. Here, we report the case of an adult patient with EPT presenting as nasal clicks who was effectively treated with botulinum toxin injection.
A previously healthy 51-year-old man presented at our hospital with a chief complaint of clicking sounds heard in the nose. He mentioned that the noise was audible to others and disappeared during sleep. He had excessive phlegm for two years and pharyngalgia for one week. His birth, growth and developmental history were all normal. He had no history of head trauma, chronic ear disease, or neurological disorder. None of his family members had a history of nasal clicks or tinnitus. The patient had been very uncomfortable due to the persistent sound.
Physical examination and preliminary diagnosis
An otolaryngologist performed physical examination of the nose, mouth and pharynx; and found that the audible “clicking” noise originated from the nose (Additional file 1: Video S1). No anomaly other than a fast rhythmic tremor of the soft palate was observed upon physical examination. Other muscles in the pharynx, mouth and eyes did not seem to be involved based on these examinations. Results of audiometry, tympanometry and neurologic examinations including cranial magnetic resonance imaging (MRI) and neurological physical examinations were all normal. Rhythmic palatal movements produced a high-pitched “clicking” sound with a frequency of approximately 100 clicks per minute (Additional file 1: Video S1, Additional file 2: Video S2 and Additional file 3: Video S3). The examiner could clearly hear the sound at a distance of 10 cm from the nasal tip. When the patient was asked to tilt his neck slightly backward, the noise was reduced (Additional file 4: Video S4).
Additional file 1: Video S1. “Clicking” noise and video recorded by cellphone. (MP4 1840 kb)
Additional file 2: Video S2. Oropharyngeal examination video recorded by endoscopy. (MP4 1700 kb)
Additional file 3: Video S3. Nasopharyngeal examination video recorded by endoscopy. (MP4 7560 kb)
Additional file 4: Video S4. Tremor ceased when tilted backward. (MP4 6310 kb)
Laboratory results including routine blood work, antinuclear antibody analysis, thyroid tests, and hepatic and renal functions
Hepatitis B virus
HIV antibodies (screen)
Treponema pallidum specific antibody
Electrolytes, liver and kidney function
0 ~ 50
Glutamic oxalacetic transaminase
15 ~ 45
45 ~ 125
10 ~ 60
61.0 ~ 79.0
34.0 ~ 48.0
24.8 ~ 38.8
1.2 ~ 2.0
6.8 ~ 34.2
1.7 ~ 8.6
4.8 ~ 25.0
3.90 ~ 6.10
2.90 ~ 8.20
50.0 ~ 133.0
0.03 ~ 0.15
149 ~ 416
137.0 ~ 147.0
3.50 ~ 5.30
99.0 ~ 110.0
Routine stool test
White blood cells (stool)
/High power field
Red blood cells (stool)
/High power field
/Low power field
Ova of roundworm
/High power field
/High power field
/Low power field
/Low power field
/Low power field
Squamous epithelial cell
/Low power field
Urine occult blood
Weakly positive (±)
Urine acetone bodies
Qualitative test of urinary protein
Weakly positive (±)
Urine specific gravity
1.003 ~ 1.03
4.6 ~ 8
12.00 ~ 15.00
Normal controls (PT)
International normalized ratio
0.85 ~ 1.15
Activated partial thromboplastin time
30.00 ~ 45.00
Normal controls (APTT)
14.00 ~ 18.00
2.00 ~ 4.00
The sample retained for three days
4 ~ 10
Ratio of neutrophil
Ratio of lymphocyte
Ratio of monocytes
Ratio of eosinophils
Ratio of basophils
Ratio of immature granulocytes
immature granulocyte count
120 ~ 160
4 ~ 5.5
0.4 ~ 0.54
Mean corpuscular volume
80 ~ 100
Mean corpuscular hemoglobin
27 ~ 34
Mean corpuscular-hemoglobin concentration
320 ~ 360
Red cell distribution width-CV
11.6 ~ 14.6
Red cell distribution width-SD
100 ~ 300
0.11 ~ 0.28
Mean platelet volume
6.5 ~ 11
Platelet-large cell ratio
Platelet distribution width
9 ~ 17
Nucleated red blood cell count
The sample retained for three days
ABO blood group system
RH(D) blood group
Thyroid function tests
0.87 ~ 1.78
6.10 - 12.20
2.50 ~ 3.90
0.61 ~ 1.12
Thyroid stimulating hormone
0.34 ~ 5.60
Found no acid fast bacilli
Nasal endoscopic examination and sinus surgery
We then performed a nasal endoscopic examination. Involuntary rhythmic movements of the nasopharyngeal lateral wall or muscles surrounding the eustachian tube were not observed (Additional file 2: Video S2 and Additional file 3: Video S3). However, the torus tubarius was found to be involved. We identified the source of the clicks on the basis of the adjacency of the sound to the nose and throat. Thus, the nasal cavity was confirmed as the source of the sound.
Endoscopic sinus surgery was performed to open the left maxillary sinus. The patient was placed in the supine position. After endotracheal intubation and routine disinfection, sterile drapes were placed and the operation commenced. An adrenaline cotton sheet was placed in the left nasal mucosa to absorb nasal secretions. The middle turbinate root, agger and uncinate process of the left side were locally anesthetized by injecting lidocaine-containing adrenaline. Under 0° endoscopy, the left uncinate process was lifted by a nasal probe, and the tail section of the uncinate process was separated. The upper and lower ends of the uncinate process adjacent to the lateral nasal wall were excised with a curved scissor. The separated uncinate process was removed with an ethmoidal sinus forcep. Thereafter, the bone at the tail end of the uncinate process was removed with a detacher and the anterior fontanelle was removed with a back biting rongeur. Thus, the natural orifice of the maxillary sinus was expanded. The maxillary sinus observed with 70° endoscopy revealed several brown bean-curd-residue-like lesions. A subsequent pathological examination confirmed that they were mould clumps. We cleaned the lesions, flushed the maxillary sinus cavity with saline via a curved suction tube, and ensured that the sinus mucosa was smooth and without any residual lesions. The left nasal cavity was filled with one expansion sponge, and the operation was completed.
However, the “clicking” noise did not stop. In a follow-up exam three months after surgery, we confirmed that the ostium of the left maxillary sinus had significantly opened up, and the sinus was clean.
Additional file 5: Video S5. Endoscopic record 8 months after injection. (MP4 22200 kb)
Auditory clicks arising from the rhythmic contraction of any of the muscles in the ear and throat [1, 2] are regarded as a primary symptom of EPT. The case of our patient was unique, because the clicks were nasal in origin.
The tremors would stop when the patient was asleep. The palatal tremor cycle could not be restored by inhibition of the trigeminal nerve using lidocaine. Neurological examination results and brain MRI scans were normal. MRI scans have shown increased signal intensity on T2 weighted images in SPT patients with injury to the dentate-olivary complex, indicating hypertrophy of the olivary nucleus [7, 8]. MRI scans of our patient revealed no evidence of structural abnormalities. Thus, SPT was excluded as a cause. To our knowledge, this is the first case of EPT associated with nasal clicks instead of otic clicks.
Otic clicks are caused by abnormal contractions of both the TVP and LVP muscles. However, objective otic clicks due to LVP contractions have not been reported since 1996 . In our patient, otic clicks were completely absent (Additional file 1: Video S1). Therefore, we suspected that some muscles of the soft palate other than the TVP such as the palatopharyngeus, palatoglossus, uvularis, and/or LVP muscles contributed to the nasal clicks. EMG results confirmed that all the above muscles were involved, except the TVP.
No specific treatment has been reported for EPT. In 1997, Cakmur et al.  reported that a 16-year old girl, who had been diagnosed with EPT at the age of six, was successfully treated with flunarizine, which is a selective calcium entry blocker with antihistaminic, antiserotoninergic and antidopaminergic activity . However, the tremor was found to recur after flunarizine was discontinued.
Campistol-Plana et al.  suggested that TPV and tubal pharynx muscles are controlled by the glossopharyngeal nerve and pharyngeal plexus. Their treatment of four pediatric patients with 2% lidocaine resulted in the gradual disappearance of palatal tremors.
Nasr and Brown reported that a 37-year-old man with a history of alcohol abuse, palatal tremors and ear clicks, and who had been hospitalized for excessive alcohol intake, has shown gradual improvement of ear clicks and frequency of tremors after being treated with lamotrigine, which is a sodium channel blocking antiepileptic drug . However, the long-term success of this drug could not be determined, because the patient discontinued its use after being discharged from the hospital.
Botulinum toxin is a neurotoxin that blocks neuromuscular transmission by inhibiting the acetylcholine receptor. Since the establishment of botulinum toxin as a safe and tolerable treatment for various therapeutic indications  including migraine , cerebral palsy , and cervical and maxillofacial conditions , it has been sporadically tested for treating EPTs.
In some cases, botulinum toxin was directly injected into the soft palate to ameliorate symptoms [20, 21]. Its efficacy in EPT stems from the fact that it binds to cholinergic nerve endings and causes muscular paralysis, thereby reducing muscular contractions. Its long-term use has not been found to cause permanent muscular degeneration [22, 23].
Recently, Tobias et al.  reported that long-term botulinum toxin injections could relieve objective tinnitus in a 78-year-old woman with minimal side effects. However, the toxin yielded temporary effects and had to be administered every 5–6 months to prevent recurrence of symptoms that could affect the daily activities of the patient.
Anis and Pollak reported that a 36-year-old woman with EPT, who had failed to respond to conservative treatment with anxiolytics, was successfully treated with 2–3 injections of botulinum toxin . Symptomatic relief was obtained within two days of injection.
Even though the source of the clicks in our patient was different from that reported in previous cases, we applied symptom-guided injections of botulinum toxin in our patient. Unlike the temporary relief provided by lidocaine injections, four simultaneous injections of botulinum toxin were found to diminish the tremors in our patient. Although our patient tolerated the treatment well, alleviation of symptoms required at least two weeks. Variability in time and dosage required for symptomatic relief in our patient and in patients reported in previous studies suggests that individualized titration of dose and frequency by close monitoring of symptoms may be critical in achieving long-term benefits, as suggested by Anis and Pollak .
Although the etiology of EPT remains unclear, some patients were found to have minor ailments  or symptoms such as otitis media, fever, or tonsillitis before the occurrence of EPTs. Our patient had excessive phlegm for two years and pharyngalgia for one week. We believe that these symptoms could be related to the etiology of EPT, because they were spontaneously relieved within 15 days after botulinum toxin treatment. Additional studies will be required to determine the pathogenesis of EPT with nasal clicks, as well as the occurrence of phlegm and pharyngalgia.
Tinnitus is the most common symptom of EPT. In this study, we report the first case of a patient with EPT who presented with nasal clicks, instead of objective pulsatile tinnitus. Similar to previous reports, botulinum toxin injections were found to alleviate symptoms and improve the quality of life of the patient for up to three months. Although the detailed pathophysiology and etiology of EPT that presented with nasal clicks remains unclear, we recommend that otolaryngologists should expect this rare occurrence in the clinical setting. Patients with this rare disorder usually have a poor social life. Therefore, clinicians should exercise care, patience and attention when handling such cases in order not to worsen the psychological status of the patient.
Essential palatal tremor
Levator veli palatini
Magnetic resonance imaging
Symptomatic palatal tremor
Tensor veli palatini
Availability of data and materials
The data and materials supporting the conclusions of this article are included within the article and its additional files.
LN conceived of the study, participated in its design and coordination and helped to draft the manuscript. YY drafted the article and revising it critically for important intellectual content. SL participated in the EMG data. BL participated in the endoscopic data. All authors read and approved the final manuscript.
The authors declare that they have no competing interests.
Consent for publication
The participant in this report signed the consent for publication of his personal data in any form (including individual details, images or videos) in this article.
Ethics approval and consent to participate
The participant in this report signed informed consent, participated voluntarily, and had the right to withdraw at any stage. Ethical approval was obtained from The Second Hospital of Wenzhou Medical University Research Ethics Committee. The ethics reference number is L-2016-17.
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- Zadikoff C, Lang AE, Klein C. The ‘essentials’ of essential palatal tremor: a reappraisal of the nosology. Brain. 2006;129:832–40.View ArticlePubMedGoogle Scholar
- Carman KB, Ozkan S, Yarar C, Yakut A. Essential palatal tremor treated with botulinum toxin. Pediatr Neurol. 2013;48:415–7.View ArticlePubMedGoogle Scholar
- Deuschl G, Mischke G, Schenck E, Schulte-Monting J, Liicking CH. Symptomatic and essential rhythmic palatal myoclonus. Brain. 1990;113:1645–72.View ArticlePubMedGoogle Scholar
- Deuschl G, Toro C, Valls-Sole J, Zeffiro T, Zee DS, Hallett M. Symptomatic and essential palatal tremor. Clinical, physiological and MRI analysis. Brain. 1994;3(17):775–88.View ArticleGoogle Scholar
- Chung EJ, Jung H, Kima SJ. A case of intractable psychogenic essential palatal tremor. J Mov Disord. 2012;5(2):55–6.View ArticlePubMedPubMed CentralGoogle Scholar
- Margari F, Giannella G, Lecce PA, Fanizzi P, Toto M, Margari L. A childhood case of symptomatic essential and psychogenic palatal tremor. Neuropsychiatr Dis Treat. 2011;7:223–7.View ArticlePubMedPubMed CentralGoogle Scholar
- Zan K, Li X, Zu J, et al. Clinical manifestations and MR imaging characteristics of hypertrophic olivary degeneration. Chin J Neuromed. 2013;9:953–5 [In Chinese].Google Scholar
- Kitajima M, Korogi Y, Shimomura O, Sakamoto Y, Hirai T, Miyayama H, Takahashi M. Hypertrophic olivary degeneration: MR imaging and pathologic findings. Radiology. 1994;192:539–42.View ArticlePubMedGoogle Scholar
- Morini A, Boninsegna C, Nostro M, Simonetti S, Orrico D, Moretto G, Tinazzi M. Palatal tremor suppressed by mouth opening clinical and neurophysiological correlations in two patients. J Neurol. 2005;252:1335–40.View ArticlePubMedGoogle Scholar
- Tomkinson A, Craven C, Brown MJ. Palatal myoclonus affected by neck position. J Laryngol Otol. 1995;109:61–2.PubMedGoogle Scholar
- Soso MJ, Nielsen VK, Jannetta PJ. Palatal myoclonus. Reflex activation of contractions. Arch Neurol. 1984;41:866–9.View ArticlePubMedGoogle Scholar
- Cakmur R, Idiman E, Idiman F, Baklan B, Ozkiziltan S. Essential palatal tremor successfully treated with flunarizine. Eur Neurol. 1997;38:133–4.View ArticlePubMedGoogle Scholar
- Llinas R, Yarom Y. Oscillatory properties of guinea-pig inferior olivary neurons and their pharmacological modulation: an in vitro study. J Physiol Lond. 1986;376:163–82.View ArticlePubMedPubMed CentralGoogle Scholar
- Campistol-Plana J, Majumdar A, Fernández-Alvarez E. Palatal tremor in childhood: clinical and therapeutic considerations. Dev Med Child Neurol. 2006;48:982–4.View ArticlePubMedGoogle Scholar
- Nasr A, Brown N. Palatal myoclonus responding to lamotrigine. Seizure. 2002;11:136–7.View ArticlePubMedGoogle Scholar
- Naumann M, Jankovic J. Safety of botulinum toxin type A: a systematic review and meta-analysis. Curr Med Res Opin. 2004;20:981–90.View ArticlePubMedGoogle Scholar
- Troost BT. Botulinum toxin type A (Botox) in the treatment of migraine and other headaches. Expert Rev Neurother. 2004;4(1):27–31.View ArticlePubMedGoogle Scholar
- Lukban MB, Rosales RL, Dressler D. Effectiveness of botulinum toxin A for upper and lower limb spasticity in children with cerebral palsy: a summary of evidence. J Neural Transm. 2009;116(3):319–31.View ArticlePubMedGoogle Scholar
- Ihde SK, Konstantinovic VS. The therapeutic use of botulinum toxin in cervical and maxillofacial conditions: an evidence-based review. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2007;104(2):e1–11.View ArticlePubMedGoogle Scholar
- Kutukcu Y, Imirzalioglu N, Odabasi Z. Essential palatal myoclonus in monozygotic male twins. J Neurol. 2003;250:885–6.View ArticlePubMedGoogle Scholar
- Jero J, Salmi T. Palatal myoclonus and clicking tinnitus in a 12-year-old girl- case report. Acta Otol. 2000;543:61–2.View ArticleGoogle Scholar
- Penney SE, Bruce IA, Saeed SR. Botulinum toxin is effective and safe for palatal tremor: a report of five cases and a review of the literature. J Neurol. 2006;253:857–60.View ArticlePubMedGoogle Scholar
- Stidham KR, Solomon PH, Roberson JB. Evaluation of botulinum toxin A in treatment of tinnitus. Otolaryngol Head Neck Surg. 2005;132:883–9.View ArticlePubMedGoogle Scholar
- Conill Tobías N, de Paula VC, García Callejo FJ, Marco AJ. Objective tinnitus from palatal myoclonus. Use of botulinum toxin: a case report. Acta Otorrinolaringol Esp. 2012;63(5):391–2.View ArticlePubMedGoogle Scholar
- Anis MM, Pollak N. Treatment of Palatal Myoclonus with Botulinum Toxin Injection. Case Rep Otolaryngol. 2013. doi: 10.1155/2013/231505.
- Samuel M, Kleiner-Fisman G, Lang AE. Voluntary control and a wider clinical spectrum of essential palatal tremor. Mov Disorders. 2004;19:717–9.View ArticleGoogle Scholar