Medical Hypotheses 82 (2014) 424–427
Contents lists available at ScienceDirect
Medical Hypotheses journal homepage: www.elsevier.com/locate/mehy
Concurrent posterior semicircular canal benign paroxysmal positional vertigo in patients with ipsilateral sudden sensorineural hearing loss: Is it caused by otolith particles? q Chang-Hee Kim a, Jung Eun Shin a, Hong Ju Park b, Ja-Won Koo c, Jun Ho Lee d,⇑ a
Department of Otorhinolaryngology-Head and Neck Surgery, Konkuk University Medical Center, Konkuk University School of Medicine, Republic of Korea Asan Medical Center, Ulsan University College of Medicine, Republic of Korea Seoul National University Bundang Hospital, Seoul National University College of Medicine, Republic of Korea d Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Republic of Korea b c
a r t i c l e
i n f o
Article history: Received 6 August 2013 Accepted 9 January 2014
a b s t r a c t The etiology of benign paroxysmal positional vertigo (BPPV) is still elusive even though detached otolith particles from the utricular macula are generally thought to be responsible for the pathogenesis of BPPV. Sudden sensorineural hearing loss (SSNHL), of which the etiology is also idiopathic in most cases, may accompany concurrent BPPV. This uncommon condition of concurrent BPPV with SSNHL has been assumptively explained as selective damage of the cochlea and the utricle due to viral neurolabyrinthitis. Recently, radiological evidences that inner ear hemorrhage is observed in patients with SSNHL accompanied by severe vertigo have been reported. The basic hypothesis for this study is that blood debris in the endolymphatic fluid due to inner ear hemorrhage is one of the causes of concurrent posterior semicircular canal (PSCC) BPPV in patient with ipsilateral SSNHL. In this report, we will outline the clinical findings of 4 patients with PSCC BPPV with SSNHL, and present an experimental results using whole blood in artificial endolymph to evaluate the hypothesis. Ó 2014 Elsevier Ltd. All rights reserved.
Introduction Benign paroxysmal positional vertigo (BPPV), which is characterized by a brief episode of rotatory vertigo and nystagmus elicited by change of head position, is one of the most common causes of vertigo. Posterior semicircular canal (PSCC) BPPV is the most common type of BPPV [1], which is characterized by paroxysmal nystagmus with up-beating and torsional components on Dix–Hallpike maneuver. The nystagmus is transient with latency of 1–5 s. The reversal of nystagmus is observed when the patient is put to the sitting upright position, and the fatigability of the nystagmus on repeated testing is evoked. This typical pattern of nystagmus elicited by specific head positioning test is well explained by the canalolithiasis hypothesis [2], in which the motion of free-floating material within the PSCC during the change of head q This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2012R1A1A2044883). ⇑ Corresponding author. Address: Department of Otorhinolaryngology, Seoul National University Hospital, Seoul National University College of Medicine, 101 Daehangno, Jongno-gu, Seoul 110-744, Republic of Korea. Tel.: +82 2 2072 2445; fax: +82 2 745 2387. E-mail address: [email protected] (J.H. Lee).
http://dx.doi.org/10.1016/j.mehy.2014.01.015 0306-9877/Ó 2014 Elsevier Ltd. All rights reserved.
position produces endolymphatic flow. The free-floating material is believed to be dislodged otolith particles from the utricular otoconia, and the presence of otoconial material within the PSCC of the patient with PSCC BPPV was demonstrated during canal occlusion surgery [1]. Successful treatment with specific canalith repositioning procedure (CRP) based on this theory further supports the hypothesis. While most of BPPV cases are primary or idiopathic [3], BPPV can be accompanied by ipsilateral SSNHL in 5–19% of all SSNHL patients [4–7]. In patients with concurrent BPPV and SSNHL, the PSCC was the most commonly involved canal in some reports [4,5], whereas other studies reported that the lateral semicircular canal was the most commonly involved canal [6,7]. These patients showed worse hearing outcome compared to those with idiopathic SSNHL in some reports [4,8], whereas concurrent BPPV in patients with SSNHL was not a prognostic factor for hearing recovery in other reports [6,7]. For the successful treatment of positional vertigo, more sessions of CRP were required in patients with BPPV with SSNHL than those with idiopathic BPPV [5]. The pathophysiology of secondary BPPV such as BPPV with concurrent SSNHL may differ quantitatively or qualitatively from that of idiopathic BPPV considering that clinical characteristics are different between two disease entity [9,10]. In previous reports about concurrent
425
C.-H. Kim et al. / Medical Hypotheses 82 (2014) 424–427
BPPV with ipsilateral SSNHL, selective damages to the cochlea, which results in sudden hearing loss, and the utricle, which results in otolith detachment, may be responsible for the specific clinical findings [11,12]. This ‘patch’ loss of inner ear function was thought to be more compatible with viral neurolabyrinthitis than labyrinthine infarct [11,12]. However, the evidences for utricular impairment were not found in 50% of the patients [11,12]. Schuknecht stated that inner ear hemorrhage may cause SSNHL with vertigo [13], and evidences for inner ear hemorrhage in those patients have been reported using magnetic resonance imaging (MRI) [14–16], in which, however, the characteristics of vertigo and the presence of positional nystagmus were not described in detail. Though certain hematologic diseases with bleeding tendency such as leukemia and sickle cell anemia were mainly reported to be associated with inner ear hemorrhage as a cause of SSNHL with vertigo [13,16], inner ear hemorrhage can also be found in patients with SSNHL and vertigo who had no hematologic disorders or bleeding tendency [15]. In normal condition, both perilymph and endolymph are isointense with cerebrospinal fluid (CSF) on T1- and T2-weighted MRI sequences [15]. Hyperintensity in the inner ear observed on pre-contrast T1-weighted images is known to suggest inner ear hemorrhage [14–16]. Based on the previous findings that inner ear hemorrhage is observed in some of the patients with SSNHL with vertigo, we will evaluate the hypothesis that inner ear hemorrhage can cause PSCC BPPV in patients with concurrent ipsilateral SSNHL in this study. We will also present clinical characteristics of 4 patients who developed PSCC BPPV with SSNHL to better understand the pathophysiology of this condition.
administered oral systemic steroids for the treatment of SSNHL. For the first 4 days, 60 mg/day was administered, and then the dosage was gradually tapered off during the subsequent 10 days. Intratympanic steroid injection was performed as a salvage treatment in all patients because of the failure of hearing improvement after systemic steroid therapy. A session of CRP was performed daily, which did not seem effective in treating PSCC BPPV in all patients. Even though the intensity of nystagmus on Dix–Hallpike test was much reduced after a session of CRP, it worsened again at the next day. It took 3–5 days for the resolution of positional vertigo and disappearance of positional nystagmus in the patients (Table 1). Follow-up audiometry at 3 months revealed that slight hearing recovery was observed in one patient (patient No. 3), and no improvement of hearing was observed in 3 patients (Table 1). Hypothesis The hypothesis to be evaluated is that inner ear hemorrhage is one of the causes of PSCC BPPV which is concurrently developed with ipsilateral SSNHL. If inner ear hemorrhage within the endolymphatic space occurs, blood debris including red blood cells (RBCs) in the endolymphatic fluid would settle in the lowest part
Clinical characteristics of patients with PSCC BPPV and ipsilateral SSNHL Clinical characteristics of 4 patients (3 males and 1 female, age range 49–72 years) who were diagnosed with concurrent PSCC BPPV and SSNHL on the same side were summarized in Table 1. The involved side was right in 2 patients, and left in 2 patients. Initial audiograms were obtained for all patients. The pure tone average (PTA) was calculated as the average threshold at 500, 1000, 2000 and 3000 Hz, which was worse than 100 dB in all patients (Table 1). All of four patients showed profound hearing loss. Typical nystagmus was observed on the Dix–Hallpike test to the affected side. All patients exhibited normal canal paresis (
Contents lists available at ScienceDirect
Medical Hypotheses journal homepage: www.elsevier.com/locate/mehy
Concurrent posterior semicircular canal benign paroxysmal positional vertigo in patients with ipsilateral sudden sensorineural hearing loss: Is it caused by otolith particles? q Chang-Hee Kim a, Jung Eun Shin a, Hong Ju Park b, Ja-Won Koo c, Jun Ho Lee d,⇑ a
Department of Otorhinolaryngology-Head and Neck Surgery, Konkuk University Medical Center, Konkuk University School of Medicine, Republic of Korea Asan Medical Center, Ulsan University College of Medicine, Republic of Korea Seoul National University Bundang Hospital, Seoul National University College of Medicine, Republic of Korea d Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Republic of Korea b c
a r t i c l e
i n f o
Article history: Received 6 August 2013 Accepted 9 January 2014
a b s t r a c t The etiology of benign paroxysmal positional vertigo (BPPV) is still elusive even though detached otolith particles from the utricular macula are generally thought to be responsible for the pathogenesis of BPPV. Sudden sensorineural hearing loss (SSNHL), of which the etiology is also idiopathic in most cases, may accompany concurrent BPPV. This uncommon condition of concurrent BPPV with SSNHL has been assumptively explained as selective damage of the cochlea and the utricle due to viral neurolabyrinthitis. Recently, radiological evidences that inner ear hemorrhage is observed in patients with SSNHL accompanied by severe vertigo have been reported. The basic hypothesis for this study is that blood debris in the endolymphatic fluid due to inner ear hemorrhage is one of the causes of concurrent posterior semicircular canal (PSCC) BPPV in patient with ipsilateral SSNHL. In this report, we will outline the clinical findings of 4 patients with PSCC BPPV with SSNHL, and present an experimental results using whole blood in artificial endolymph to evaluate the hypothesis. Ó 2014 Elsevier Ltd. All rights reserved.
Introduction Benign paroxysmal positional vertigo (BPPV), which is characterized by a brief episode of rotatory vertigo and nystagmus elicited by change of head position, is one of the most common causes of vertigo. Posterior semicircular canal (PSCC) BPPV is the most common type of BPPV [1], which is characterized by paroxysmal nystagmus with up-beating and torsional components on Dix–Hallpike maneuver. The nystagmus is transient with latency of 1–5 s. The reversal of nystagmus is observed when the patient is put to the sitting upright position, and the fatigability of the nystagmus on repeated testing is evoked. This typical pattern of nystagmus elicited by specific head positioning test is well explained by the canalolithiasis hypothesis [2], in which the motion of free-floating material within the PSCC during the change of head q This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2012R1A1A2044883). ⇑ Corresponding author. Address: Department of Otorhinolaryngology, Seoul National University Hospital, Seoul National University College of Medicine, 101 Daehangno, Jongno-gu, Seoul 110-744, Republic of Korea. Tel.: +82 2 2072 2445; fax: +82 2 745 2387. E-mail address: [email protected] (J.H. Lee).
http://dx.doi.org/10.1016/j.mehy.2014.01.015 0306-9877/Ó 2014 Elsevier Ltd. All rights reserved.
position produces endolymphatic flow. The free-floating material is believed to be dislodged otolith particles from the utricular otoconia, and the presence of otoconial material within the PSCC of the patient with PSCC BPPV was demonstrated during canal occlusion surgery [1]. Successful treatment with specific canalith repositioning procedure (CRP) based on this theory further supports the hypothesis. While most of BPPV cases are primary or idiopathic [3], BPPV can be accompanied by ipsilateral SSNHL in 5–19% of all SSNHL patients [4–7]. In patients with concurrent BPPV and SSNHL, the PSCC was the most commonly involved canal in some reports [4,5], whereas other studies reported that the lateral semicircular canal was the most commonly involved canal [6,7]. These patients showed worse hearing outcome compared to those with idiopathic SSNHL in some reports [4,8], whereas concurrent BPPV in patients with SSNHL was not a prognostic factor for hearing recovery in other reports [6,7]. For the successful treatment of positional vertigo, more sessions of CRP were required in patients with BPPV with SSNHL than those with idiopathic BPPV [5]. The pathophysiology of secondary BPPV such as BPPV with concurrent SSNHL may differ quantitatively or qualitatively from that of idiopathic BPPV considering that clinical characteristics are different between two disease entity [9,10]. In previous reports about concurrent
425
C.-H. Kim et al. / Medical Hypotheses 82 (2014) 424–427
BPPV with ipsilateral SSNHL, selective damages to the cochlea, which results in sudden hearing loss, and the utricle, which results in otolith detachment, may be responsible for the specific clinical findings [11,12]. This ‘patch’ loss of inner ear function was thought to be more compatible with viral neurolabyrinthitis than labyrinthine infarct [11,12]. However, the evidences for utricular impairment were not found in 50% of the patients [11,12]. Schuknecht stated that inner ear hemorrhage may cause SSNHL with vertigo [13], and evidences for inner ear hemorrhage in those patients have been reported using magnetic resonance imaging (MRI) [14–16], in which, however, the characteristics of vertigo and the presence of positional nystagmus were not described in detail. Though certain hematologic diseases with bleeding tendency such as leukemia and sickle cell anemia were mainly reported to be associated with inner ear hemorrhage as a cause of SSNHL with vertigo [13,16], inner ear hemorrhage can also be found in patients with SSNHL and vertigo who had no hematologic disorders or bleeding tendency [15]. In normal condition, both perilymph and endolymph are isointense with cerebrospinal fluid (CSF) on T1- and T2-weighted MRI sequences [15]. Hyperintensity in the inner ear observed on pre-contrast T1-weighted images is known to suggest inner ear hemorrhage [14–16]. Based on the previous findings that inner ear hemorrhage is observed in some of the patients with SSNHL with vertigo, we will evaluate the hypothesis that inner ear hemorrhage can cause PSCC BPPV in patients with concurrent ipsilateral SSNHL in this study. We will also present clinical characteristics of 4 patients who developed PSCC BPPV with SSNHL to better understand the pathophysiology of this condition.
administered oral systemic steroids for the treatment of SSNHL. For the first 4 days, 60 mg/day was administered, and then the dosage was gradually tapered off during the subsequent 10 days. Intratympanic steroid injection was performed as a salvage treatment in all patients because of the failure of hearing improvement after systemic steroid therapy. A session of CRP was performed daily, which did not seem effective in treating PSCC BPPV in all patients. Even though the intensity of nystagmus on Dix–Hallpike test was much reduced after a session of CRP, it worsened again at the next day. It took 3–5 days for the resolution of positional vertigo and disappearance of positional nystagmus in the patients (Table 1). Follow-up audiometry at 3 months revealed that slight hearing recovery was observed in one patient (patient No. 3), and no improvement of hearing was observed in 3 patients (Table 1). Hypothesis The hypothesis to be evaluated is that inner ear hemorrhage is one of the causes of PSCC BPPV which is concurrently developed with ipsilateral SSNHL. If inner ear hemorrhage within the endolymphatic space occurs, blood debris including red blood cells (RBCs) in the endolymphatic fluid would settle in the lowest part
Clinical characteristics of patients with PSCC BPPV and ipsilateral SSNHL Clinical characteristics of 4 patients (3 males and 1 female, age range 49–72 years) who were diagnosed with concurrent PSCC BPPV and SSNHL on the same side were summarized in Table 1. The involved side was right in 2 patients, and left in 2 patients. Initial audiograms were obtained for all patients. The pure tone average (PTA) was calculated as the average threshold at 500, 1000, 2000 and 3000 Hz, which was worse than 100 dB in all patients (Table 1). All of four patients showed profound hearing loss. Typical nystagmus was observed on the Dix–Hallpike test to the affected side. All patients exhibited normal canal paresis (
