BRIEF COMMUNICATIONS
Drop Attacks with Me&re’s Syndrome R. W. Baloh, MD, K. Jacobson, BA, and T. Winder, MD ~
~
~
We report the clinical features of 12 patients with drop attacks associated with Meniere’s syndrome. Each described a sensation of being pushed, thrown, or knocked to the ground or a sudden illusion of movement of the environment that led to a fall. These episodes were not accompanied by symptoms of their typical attacks of Meniere’s syndrome. The drop attacks occurred early and late in the course of the disease; they were the initial manifestation in 1 patient. I n the majority the episodes spontaneously remitted, although Meniere’s syndrome continued to progress. These attacks probably result from a sudden mechanical deformation of the otolithic membrane of the utricle or saccule due to pressure gradients within the inner ear. They are important to recognize because their prognosis is relatively benign compared to other causes of drop attacks. Baloh RW, Jacobson K, Winder T. Drop attacks with Meniere’s syndrome. Ann Neurol 1990;28:384-387
In 1936, Tumarkin first described sudden falling spells in patients with Meniere’s syndrome [l}. These drop attacks occurred independent of the more typical episodes of vertigo, tinnitus, hearing loss, and ear pressure. For example, one patient was standing near his desk talking to a client when he suddenly fell to the floor. ‘The thing came on like a bolt from the blue, but he was able immediately to assure onlookers that he was all right and almost immediately got up and carried on.” Tumarkin speculated that these falls resulted from a mechanical deformation of the otolith organs (an “otolithic catastrophe”). The natural history of drop attacks with Meniere’s syndrome is unclear. Black and colleagues 121reported that drop attacks occurred only late in the course of Meniere’s syndrome. They concluded that surgical intervention was necessary since medical treatment was ineffective. Janten and Russell 131 found that drop attacks occurred anytime from 3 to 20 years after onset of Meniere’s syndrome. They emphasized that spontaneous remissions were common and recommended conservative management. In an attempt to resolve
From the Department of Neurology and Division of Head and Neck Surgery, UCLA Medical Center, Los Angeles, CA.
Received Dec 14, 1989, and in revised form Mar 20, 1990. Accepted for publication Mar 22, 1990. Address correspondence to Dr Baloh, Dept. of Neurology, UCLA Medical Center, Los Angeles, CA 90024-1769.
384
these conflicting opinions, we reviewed the records of 175 patients with Meniere’s syndrome seen personally by the senior author over the past 10 years. Twelve of them had drop attacks typical of those described by Tumarkin. Surprisingly, we found that drop attacks could occur at any time during the course of Meniere’s syndrome, and was the initial manifestation in 1 patient.
Case Material The criterion for inclusion in this series was that a patient with Meniere’s syndrome reported a sudden fall that occurred without warning and without loss of consciousness. There were no associated neurological symptoms and all had normal results on neurological examination. Three categories of Meniere’s syndrome were defined: definite, probable, and delayed (Table 1) [4]. Patients with definite Meniere’s syndrome had documented fluctuating hearing levels during their episodes of vertigo. Patients with probable Meniere’s syndrome reported a subjective decrease in hearing with their episodes of vertigo (but no audiogram was performed during an attack). All patients in the definite and probable categories, however, had typical low-frequencysensorineural hearing loss documented between attacks of vertigo. Patients with delayed Meniere’s syndrome developed episodic vertigo many years after suffering a profound unilateral sensorineural hearing loss, presumably caused by a virus [5]. Each patient filled out a standard “dizziness” questionnaire. The history and examination were conducted by the senior author. Follow-up ranged from 4 months to 13 years. All patients underwent standard auditory and vestibular function testing 141. Eight of the 12 patients were referred specifically for evaluation of the drop attacks; the other 4 reported drop attacks while they were evaluated for management of their more typical Meniere’s attacks.
Results Description of Attacks One of two features was present when patients described their drop attacks (Table 2). They reported either that they were being pushed or shoved to the ground or that the environment suddenly moved, leading to a fall. For example, a 57-year-old housewife with Meniere’s syndrome of 1% years’ duration was sitting at the dining room table when she suddenly fell onto her food without warning. With this initial attack she was certain that someone pushed her from behind. After a subsequent episode occurred when she was alone, she accepted the fact that it only felt as though she were pushed. A 38-year-old professor with Meniere’s syndrome of 2 years’ duration was sitting at his lab bench when he had the illusion that the bench suddenly moved away from him, causing him to fall backward from the stool to the floor. A subsequent episode occurred while he was standing; h e felt the room move away from him, causing him to fall backward to the floor.
Copyright 0 1990 by the American Neurological Association
Table 1. Summary of Clinical Data on 12 Patients with Drop Attacks and Meniere’s Syndrome Patient No.
1 2
3 4 5 6 7 8
9 10 11
12
Sex
Type of Meniere’sa
F F F F M M M F M M M F
Definite Probable Probable Probable Definite Definite Definite Definite Definite Delayed Delayed Delayed
Age at Onset of Meniere’s (yr)
47 56
43 57 55 58 47 64 36 54 76
34
Age at Onset of Drop Attacks (yr) 76 57 48 57 61 73 72 67 38 55 76 36
No. of Drop Attacks
3 4
18 2
5 3
4 5 2 2 6 12
Interval of Drop Attacks (yr)
Time since Last Attack (Yr)
0.6 0.17 6 0.6 1
0.6 4.5 0.3 8 0.3 -
0.25 0.5 1 0.5 0.17 2
0.33
0.5b 0.75
13
5 4
3
“Definite: documented fluctuating hearing levels; probable: typical episodes but no documented fluctuating hearing level; delayed: endolymphatic hydrops develops in ear previously damaged by virai infection. bSince vestibular nerve section.
Table 2. Description of Typical Drop Attack in Each Patient Patient
Description
No. 1 2
3 4
5 6
7 8
9 10
11 12
Sudden fall to ground as though pushed. While sitting at dining table, fell forward into food, as if pushed from behind. Sensation of being slapped on the side of head, fell to the ground. “Knocking episodes,” first occurred while sitting in taxi, thought someone pushed her to the floor. Suddenly “thrown” to the ground from sitting or standing position. While sitting, had illusion that the chair was falling backward, fell forward onto the floor. Sudden fall to ground, as though pushed. Sudden fall as though pushed, hit head on concrete, dazed but no loss of consciousness. Sitting at lab bench, thought bench suddenly moved away from him, fell backward from stool to floor. Sensation of sudden push to the ground along with an electric shock-like sensation in center of head. Sudden fall from a bar stool (before first drink) with illusion of tilting of the environment. Room suddenly tilts, must grab onto something or fall to ground “like an earthquake.”
Natwal Histovy The timing between the onset of typical symptoms of Meniere’s syndrome and the first drop attack varied from less than 1 year to 29 years. In 1 patient, a drop attack was the initial manifestation of Meniere’s syndrome. While riding in a taxicab, a 56-year old woman suddenly fell over onto the floor, certain that someone had pushed her from the side even though there was no one else in the back seat of the cab. Two months later, she had her first episode of vertigo, tinnitus, and unilateral hearing loss, lasting several hours. Three months later, she had a second drop attack. Over the subsequent 9 years, she had no further drop attacks but continued to have recurrent episodes of vertigo. At the time of writing, she had a bilateral low-frequency sensorineural hearing loss typical of bilateral Meniere’s syndrome. One other patient (Patient 11) had the onset of drop attacks within the first year of typical symptoms of Meniere’s syndrome and 4 others had the onset of drop attacks within the first 2 years. All 3 patients with delayed Meniere’s syndrome had the onset of drop attacks within 2 years after the onset of episodic vertigo. The total number of drop attacks varied from 2 to 18 but only 2 of 12 patients had more than 6 attacks. The attacks typically occurred in a flurry during a period of l year or less and then spontaneously remitted. Only 2 patients had attacks occurring over an interval longer than 1 year. One unusual patient had approximately 18 drop attacks over an interval of 6 years at a rate of about 3 attacks per year. She continued to have more typical attacks of vertigo and was on disability because of these symptoms. Follow-up since the last
Brief Communication: Baloh et al: Drop Attacks with Meniere’s Syndrome
385
drop attack varied from less than 1 year to as long as 13 years. Only 1 patient (Patient 7) opted for surgical treatment and he has been free of drop attacks since undergoing a vestibular nerve section.
Luboratovy Results As noted already, all patients exhibited sensorineural hearing loss, typical of Meniere’s syndrome. Three of 12 developed bilateral hearing loss. All but 2 patients (Patients 4 and 13) had a significantly decreased response to caloric stimulation [4] in the ear with impaired hearing. Patient 4 had a significant directional preponderance to caloric stimulation [4]while Patient 12 had caloric responses within normal limits. Management Treatment consisted of a salt-restriction diet (in the range of 1 to 2 gm of sodium per day) along with antivertiginous medication (eg, meclizine, promethazine hydrochloride) for symptomatic relief of the more typical attacks of Meniere’s syndrome. It is impossible to determine whether the salt-restriction diet altered the natural history of the drop attacks but several of the patients noted that they could reliably precipitate one of their more typical episodes of vertigo if they broke their diet and ate a high salt-content meal. Discussion Although drop attacks associated with Meniere’s syndrome might be confused with those associated with cardiac and neurological disorders, a careful history should allow the clinician to separate these different causes of sudden falls. With Meniere’s syndrome, the patient reports a sensation of being pushed or shoved to the ground, often noting an illusion of movement of the environment just before the f d . Kuhl {GI noted that patients fall “like a tree” often in the same direction with repeated drop attacks. Other causes of drop attacks typically result in a “slumping” to the ground due to a sudden loss of tone in the lower extremities [7]. Patients with Meniere’s syndrome are able to stand up immediately after a drop attack; patients with other types of drop attacks often require a minute or so before they feel strong enough to resume normal activity. Both types of drop attacks can result in injury but surprisingly only a few of our patients with drop attacks due to Meniere’s syndrome suffered injuries. Unlike prior reports {2, 31 we found that drop attacks could occur at any time during the course of Meniere’s syndrome. In 1 patient they were the initial manifestation of the disorder; in several they occurred within the first 2 years of onset of Meniere’s syndrome. Like Janzen and Russell [3], we found that drop attacks with Meniere’s syndrome tended to occur
in a flurry followed by spontaneous remission. An exception is the patient (Patient 3) who experienced an average of 3 drop attacks per year over a 6-year period. She was on disability because of Meniere’s syndrome but refused surgery. To date she has not had any serious injuries with these repetitive drop attacks. The pathophysiological mechanism of drop attacks associated with Meniere’s syndrome is unknown. There are two types of motion detectors in the inner ear: the semicircular canals, which sense angular acceleration, and the utricle and saccule, which sense linear acceleration (including gravity) [41. Stimulation of the former results in an illusion of angular rotation whereas stimulation of the latter produces a sensation of linear displacement or tilt. The description of a sudden push or shove along with an illusion of linear displacement or tilt of the environment in patients with drop attacks due to Meniere’s syndrome suggests a sudden stimulation of the otolithic membrane of the utricle, saccule, or both. This could result from a mechanical deformation due to pressure differentials within the inner ear or from rapid change in the electrolyte content of the endolymph due to rupture of the membranous labyrinth. The burst of neural impulses originating from the otolith would pass directly into the vestibulospinal reflex pathways and to cortical centers that monitor spatial orientation. A sudden fall could result directly from vestibulospinal activation of motoneurons or indirectly from motor reflexes activated from higher centers. Brandt and associates {8] documented a similar phenomenon in a professional horn player who complained of attacks of a counterclockwise tilt of the visual scene, along with a sudden falling backward elicited by a loud sound applied to the left ear. This so-called otolithic Tullio phenomenon resulted from a hypermobile stapes footplate that produced a sudden mechanical stimulation of the otolith. Eye movement recordings and posturography documented a sound-induced ocular tilt reaction and increased body sway predominantly from right backward to left forward. Although such recordings have not been made in patients with drop attacks due to Meniere’s syndrome, one might expect similar oculomotor and postural effects. Out of 175 patients with Meniere’s syndrome seen during a 10-year period, we found only 12 patients with drop attacks. Black and colleagues {2] reported a similar incidence of drop attacks in patients with Meniere’s syndrome (11 out of 200). Why do so few patients with Meniere’s syndrome develop drop attacks? The findings on quantitative auditory and vestibular function testing in patients with drop attacks compared to patients with Meniere’s syndrome without drop attacks were similar. Furthermore, there were no clinical features that could reliably differentiate those with and those without drop attacks. Kuhl sug-
386 Annals of Neurology Vol 28 No 3 September 1990
gested that drop attacks can occur with other peripheral vestibular disorders in addition to Meniere’s syndrome {b]. He provided minimal details regarding these patients, however. Finally, although our data do not allow us to speculate on the effectiveness of different types of treatments for drop attacks associated with Meniere’s syndrome, we cannot agree with Black and associates that the treatment of choice is surgery. As did Janzen and Russell {3}, we found that most patients have a spontaneous remission, regardless of the treatment. In a few patients the drop attacks are either so dangerous or intractable that surgical intervention is warranted. Assuming that the diagnosis of unilateral Meniere’s syndrome is well documented, one can anticipate that the drop attacks will stop after surgery. Regarding the type of surgery, Black and associates {2) and Janzen and Russell {3} agreed that endolymphatic shunt operations are not effective for controlling the drop attacks associated with Meniere’s syndrome. Vestibular nerve section is the procedure of choice in patients with serviceable hearing, whereas a labyrinthectomy might be considered in patients with profound hearing loss [2f. Odkvist and Bergenius {9} suggested that intratympanic injection of gentarnycin was equally effective in stopping the drop attacks associated with Meniere’s syndrome.
Dr Baloh is supported by NIH grant DC00097.
References 1. Tumarkin A. The otolithic catastrophe: a new syndrome. Br Med J 1936;1:175-177 2. Black JX,Effron MZ, Burns DS. Diagnosis and management of drop attacks of vestibular origin: Tumarlun’s otolithic crises. J Otolaryngol Head Neck Surg 1982;90:256-262 3. Janzen VD, Russell RD. Conservative management of Tumarkin’s otolithic crises. J Otolaryngol, 1988;17:359-361 4. Baloh RW, Honrubia V. Clinical neurophysiology of the vestibular system. 2nd ed. Philadelphia: F.A. Davis, 1990 5. Schuknecht HF. Delayed endolymphatic hydrops. Ann Otol 1978;87:743-748 6. Kuhl W. Vestibular-cerebral syncopes. Dtsch Med Wochenschr 1980;105:41-42 7. Kubala MJ, Millikan CH. Diagnosis, pathogenesis and treatment of “drop attacks.” Arch Neurol 1964;11:107-113 8. Brandt T, Dieterich M, Fries W. Otolithic Tullio phenomenon paroxysmal ocular tilt reaction. Adv Ototypically presents rhinolaryngol 1988;42:153-156 9. Odkvist LN, Bergenius J. Drop attacks in Meniere’s disease. Acca Otolaryngol Suppl (Stockh) 1988;55:82-85
Electroencephalography Laboratory Diagnosis of Prolonged QT Interval Sidney M. Gospe, Jr, MD, PhD,”t and Andrew J. Gabor, MD, PhD’ Patients with prolongation of the Q T interval are at risk for significant neurological morbidity and mortality secondary to ventricular tachyarrhythmias. These patients frequently undergo electroencephalographic (EEG) examination to evaluate episodes of loss of consciousness, which may be associated with convulsions. Electrocardiogram recording as a part of the EEG is a simple and common practice, but analysis for possible Q T prolongation is not routinely performed by electroencephalographers. This is, in part, due to the fact that while calculation of the corrected QT interval is straight forward, a calculator is generally required. A nomogram that is presented simplifies determination of the corrected QT interval, facilitating diagnosis of prolongation of the QT interval in the EEG laboratory. Gospe SM Jr, Gabor AJ. Electroencephalography laboratory diagnosis of prolonged QT interval. Ann Neurol 1990;28:387-390 Two familial syndromes of QT prolongation have been well described { 1-31. Patients with either of these conditions are subject to ventricular dysrhythmias, which can lead to palpitations and syncope. Frequently these episodes are induced by exercise or excitement. Affected patients can present with seizures, and diagnosis may be delayed until an electrocardiogram (ECG) is obtained [4- lo]. If unrecognized, these disorders frequently lead to inappropriate treatment with anticonvulsants and to sudden death or severe neurological morbidity secondary to hypoxic ischemic brain injury. Prior to diagnosis, many patients with these conditions undergo electroencephalographic (EEG) examinations as part of an evaluation for syncope or seizures. During a routine EEG examination, ECG activity is frequently recorded for a portion of the study. We previously reported on two siblings with the autosomal dominant form of hereditary QT prolongation (Romano-Ward syndrome) for whom EEG examinations performed several years prior to the actual diagnosis contained ECG data documenting the abnormalFrom the Departments of *Neurology and ?Pediatrics, School of Medicine, University of California, Davis, Davis, CA. Received Jan 19, 1990, and in revised form Mar 27. Accepted for publication Mar 30, 1990. Address correspondence to Dr Gospe, Department of Neurology, University of California, Davis Medical Center, 2315 Stockton Blvd., Sacramento, CA 95817.
Copyright 0 1990 by the American Neurological Association
387
Drop Attacks with Me&re’s Syndrome R. W. Baloh, MD, K. Jacobson, BA, and T. Winder, MD ~
~
~
We report the clinical features of 12 patients with drop attacks associated with Meniere’s syndrome. Each described a sensation of being pushed, thrown, or knocked to the ground or a sudden illusion of movement of the environment that led to a fall. These episodes were not accompanied by symptoms of their typical attacks of Meniere’s syndrome. The drop attacks occurred early and late in the course of the disease; they were the initial manifestation in 1 patient. I n the majority the episodes spontaneously remitted, although Meniere’s syndrome continued to progress. These attacks probably result from a sudden mechanical deformation of the otolithic membrane of the utricle or saccule due to pressure gradients within the inner ear. They are important to recognize because their prognosis is relatively benign compared to other causes of drop attacks. Baloh RW, Jacobson K, Winder T. Drop attacks with Meniere’s syndrome. Ann Neurol 1990;28:384-387
In 1936, Tumarkin first described sudden falling spells in patients with Meniere’s syndrome [l}. These drop attacks occurred independent of the more typical episodes of vertigo, tinnitus, hearing loss, and ear pressure. For example, one patient was standing near his desk talking to a client when he suddenly fell to the floor. ‘The thing came on like a bolt from the blue, but he was able immediately to assure onlookers that he was all right and almost immediately got up and carried on.” Tumarkin speculated that these falls resulted from a mechanical deformation of the otolith organs (an “otolithic catastrophe”). The natural history of drop attacks with Meniere’s syndrome is unclear. Black and colleagues 121reported that drop attacks occurred only late in the course of Meniere’s syndrome. They concluded that surgical intervention was necessary since medical treatment was ineffective. Janten and Russell 131 found that drop attacks occurred anytime from 3 to 20 years after onset of Meniere’s syndrome. They emphasized that spontaneous remissions were common and recommended conservative management. In an attempt to resolve
From the Department of Neurology and Division of Head and Neck Surgery, UCLA Medical Center, Los Angeles, CA.
Received Dec 14, 1989, and in revised form Mar 20, 1990. Accepted for publication Mar 22, 1990. Address correspondence to Dr Baloh, Dept. of Neurology, UCLA Medical Center, Los Angeles, CA 90024-1769.
384
these conflicting opinions, we reviewed the records of 175 patients with Meniere’s syndrome seen personally by the senior author over the past 10 years. Twelve of them had drop attacks typical of those described by Tumarkin. Surprisingly, we found that drop attacks could occur at any time during the course of Meniere’s syndrome, and was the initial manifestation in 1 patient.
Case Material The criterion for inclusion in this series was that a patient with Meniere’s syndrome reported a sudden fall that occurred without warning and without loss of consciousness. There were no associated neurological symptoms and all had normal results on neurological examination. Three categories of Meniere’s syndrome were defined: definite, probable, and delayed (Table 1) [4]. Patients with definite Meniere’s syndrome had documented fluctuating hearing levels during their episodes of vertigo. Patients with probable Meniere’s syndrome reported a subjective decrease in hearing with their episodes of vertigo (but no audiogram was performed during an attack). All patients in the definite and probable categories, however, had typical low-frequencysensorineural hearing loss documented between attacks of vertigo. Patients with delayed Meniere’s syndrome developed episodic vertigo many years after suffering a profound unilateral sensorineural hearing loss, presumably caused by a virus [5]. Each patient filled out a standard “dizziness” questionnaire. The history and examination were conducted by the senior author. Follow-up ranged from 4 months to 13 years. All patients underwent standard auditory and vestibular function testing 141. Eight of the 12 patients were referred specifically for evaluation of the drop attacks; the other 4 reported drop attacks while they were evaluated for management of their more typical Meniere’s attacks.
Results Description of Attacks One of two features was present when patients described their drop attacks (Table 2). They reported either that they were being pushed or shoved to the ground or that the environment suddenly moved, leading to a fall. For example, a 57-year-old housewife with Meniere’s syndrome of 1% years’ duration was sitting at the dining room table when she suddenly fell onto her food without warning. With this initial attack she was certain that someone pushed her from behind. After a subsequent episode occurred when she was alone, she accepted the fact that it only felt as though she were pushed. A 38-year-old professor with Meniere’s syndrome of 2 years’ duration was sitting at his lab bench when he had the illusion that the bench suddenly moved away from him, causing him to fall backward from the stool to the floor. A subsequent episode occurred while he was standing; h e felt the room move away from him, causing him to fall backward to the floor.
Copyright 0 1990 by the American Neurological Association
Table 1. Summary of Clinical Data on 12 Patients with Drop Attacks and Meniere’s Syndrome Patient No.
1 2
3 4 5 6 7 8
9 10 11
12
Sex
Type of Meniere’sa
F F F F M M M F M M M F
Definite Probable Probable Probable Definite Definite Definite Definite Definite Delayed Delayed Delayed
Age at Onset of Meniere’s (yr)
47 56
43 57 55 58 47 64 36 54 76
34
Age at Onset of Drop Attacks (yr) 76 57 48 57 61 73 72 67 38 55 76 36
No. of Drop Attacks
3 4
18 2
5 3
4 5 2 2 6 12
Interval of Drop Attacks (yr)
Time since Last Attack (Yr)
0.6 0.17 6 0.6 1
0.6 4.5 0.3 8 0.3 -
0.25 0.5 1 0.5 0.17 2
0.33
0.5b 0.75
13
5 4
3
“Definite: documented fluctuating hearing levels; probable: typical episodes but no documented fluctuating hearing level; delayed: endolymphatic hydrops develops in ear previously damaged by virai infection. bSince vestibular nerve section.
Table 2. Description of Typical Drop Attack in Each Patient Patient
Description
No. 1 2
3 4
5 6
7 8
9 10
11 12
Sudden fall to ground as though pushed. While sitting at dining table, fell forward into food, as if pushed from behind. Sensation of being slapped on the side of head, fell to the ground. “Knocking episodes,” first occurred while sitting in taxi, thought someone pushed her to the floor. Suddenly “thrown” to the ground from sitting or standing position. While sitting, had illusion that the chair was falling backward, fell forward onto the floor. Sudden fall to ground, as though pushed. Sudden fall as though pushed, hit head on concrete, dazed but no loss of consciousness. Sitting at lab bench, thought bench suddenly moved away from him, fell backward from stool to floor. Sensation of sudden push to the ground along with an electric shock-like sensation in center of head. Sudden fall from a bar stool (before first drink) with illusion of tilting of the environment. Room suddenly tilts, must grab onto something or fall to ground “like an earthquake.”
Natwal Histovy The timing between the onset of typical symptoms of Meniere’s syndrome and the first drop attack varied from less than 1 year to 29 years. In 1 patient, a drop attack was the initial manifestation of Meniere’s syndrome. While riding in a taxicab, a 56-year old woman suddenly fell over onto the floor, certain that someone had pushed her from the side even though there was no one else in the back seat of the cab. Two months later, she had her first episode of vertigo, tinnitus, and unilateral hearing loss, lasting several hours. Three months later, she had a second drop attack. Over the subsequent 9 years, she had no further drop attacks but continued to have recurrent episodes of vertigo. At the time of writing, she had a bilateral low-frequency sensorineural hearing loss typical of bilateral Meniere’s syndrome. One other patient (Patient 11) had the onset of drop attacks within the first year of typical symptoms of Meniere’s syndrome and 4 others had the onset of drop attacks within the first 2 years. All 3 patients with delayed Meniere’s syndrome had the onset of drop attacks within 2 years after the onset of episodic vertigo. The total number of drop attacks varied from 2 to 18 but only 2 of 12 patients had more than 6 attacks. The attacks typically occurred in a flurry during a period of l year or less and then spontaneously remitted. Only 2 patients had attacks occurring over an interval longer than 1 year. One unusual patient had approximately 18 drop attacks over an interval of 6 years at a rate of about 3 attacks per year. She continued to have more typical attacks of vertigo and was on disability because of these symptoms. Follow-up since the last
Brief Communication: Baloh et al: Drop Attacks with Meniere’s Syndrome
385
drop attack varied from less than 1 year to as long as 13 years. Only 1 patient (Patient 7) opted for surgical treatment and he has been free of drop attacks since undergoing a vestibular nerve section.
Luboratovy Results As noted already, all patients exhibited sensorineural hearing loss, typical of Meniere’s syndrome. Three of 12 developed bilateral hearing loss. All but 2 patients (Patients 4 and 13) had a significantly decreased response to caloric stimulation [4] in the ear with impaired hearing. Patient 4 had a significant directional preponderance to caloric stimulation [4]while Patient 12 had caloric responses within normal limits. Management Treatment consisted of a salt-restriction diet (in the range of 1 to 2 gm of sodium per day) along with antivertiginous medication (eg, meclizine, promethazine hydrochloride) for symptomatic relief of the more typical attacks of Meniere’s syndrome. It is impossible to determine whether the salt-restriction diet altered the natural history of the drop attacks but several of the patients noted that they could reliably precipitate one of their more typical episodes of vertigo if they broke their diet and ate a high salt-content meal. Discussion Although drop attacks associated with Meniere’s syndrome might be confused with those associated with cardiac and neurological disorders, a careful history should allow the clinician to separate these different causes of sudden falls. With Meniere’s syndrome, the patient reports a sensation of being pushed or shoved to the ground, often noting an illusion of movement of the environment just before the f d . Kuhl {GI noted that patients fall “like a tree” often in the same direction with repeated drop attacks. Other causes of drop attacks typically result in a “slumping” to the ground due to a sudden loss of tone in the lower extremities [7]. Patients with Meniere’s syndrome are able to stand up immediately after a drop attack; patients with other types of drop attacks often require a minute or so before they feel strong enough to resume normal activity. Both types of drop attacks can result in injury but surprisingly only a few of our patients with drop attacks due to Meniere’s syndrome suffered injuries. Unlike prior reports {2, 31 we found that drop attacks could occur at any time during the course of Meniere’s syndrome. In 1 patient they were the initial manifestation of the disorder; in several they occurred within the first 2 years of onset of Meniere’s syndrome. Like Janzen and Russell [3], we found that drop attacks with Meniere’s syndrome tended to occur
in a flurry followed by spontaneous remission. An exception is the patient (Patient 3) who experienced an average of 3 drop attacks per year over a 6-year period. She was on disability because of Meniere’s syndrome but refused surgery. To date she has not had any serious injuries with these repetitive drop attacks. The pathophysiological mechanism of drop attacks associated with Meniere’s syndrome is unknown. There are two types of motion detectors in the inner ear: the semicircular canals, which sense angular acceleration, and the utricle and saccule, which sense linear acceleration (including gravity) [41. Stimulation of the former results in an illusion of angular rotation whereas stimulation of the latter produces a sensation of linear displacement or tilt. The description of a sudden push or shove along with an illusion of linear displacement or tilt of the environment in patients with drop attacks due to Meniere’s syndrome suggests a sudden stimulation of the otolithic membrane of the utricle, saccule, or both. This could result from a mechanical deformation due to pressure differentials within the inner ear or from rapid change in the electrolyte content of the endolymph due to rupture of the membranous labyrinth. The burst of neural impulses originating from the otolith would pass directly into the vestibulospinal reflex pathways and to cortical centers that monitor spatial orientation. A sudden fall could result directly from vestibulospinal activation of motoneurons or indirectly from motor reflexes activated from higher centers. Brandt and associates {8] documented a similar phenomenon in a professional horn player who complained of attacks of a counterclockwise tilt of the visual scene, along with a sudden falling backward elicited by a loud sound applied to the left ear. This so-called otolithic Tullio phenomenon resulted from a hypermobile stapes footplate that produced a sudden mechanical stimulation of the otolith. Eye movement recordings and posturography documented a sound-induced ocular tilt reaction and increased body sway predominantly from right backward to left forward. Although such recordings have not been made in patients with drop attacks due to Meniere’s syndrome, one might expect similar oculomotor and postural effects. Out of 175 patients with Meniere’s syndrome seen during a 10-year period, we found only 12 patients with drop attacks. Black and colleagues {2] reported a similar incidence of drop attacks in patients with Meniere’s syndrome (11 out of 200). Why do so few patients with Meniere’s syndrome develop drop attacks? The findings on quantitative auditory and vestibular function testing in patients with drop attacks compared to patients with Meniere’s syndrome without drop attacks were similar. Furthermore, there were no clinical features that could reliably differentiate those with and those without drop attacks. Kuhl sug-
386 Annals of Neurology Vol 28 No 3 September 1990
gested that drop attacks can occur with other peripheral vestibular disorders in addition to Meniere’s syndrome {b]. He provided minimal details regarding these patients, however. Finally, although our data do not allow us to speculate on the effectiveness of different types of treatments for drop attacks associated with Meniere’s syndrome, we cannot agree with Black and associates that the treatment of choice is surgery. As did Janzen and Russell {3}, we found that most patients have a spontaneous remission, regardless of the treatment. In a few patients the drop attacks are either so dangerous or intractable that surgical intervention is warranted. Assuming that the diagnosis of unilateral Meniere’s syndrome is well documented, one can anticipate that the drop attacks will stop after surgery. Regarding the type of surgery, Black and associates {2) and Janzen and Russell {3} agreed that endolymphatic shunt operations are not effective for controlling the drop attacks associated with Meniere’s syndrome. Vestibular nerve section is the procedure of choice in patients with serviceable hearing, whereas a labyrinthectomy might be considered in patients with profound hearing loss [2f. Odkvist and Bergenius {9} suggested that intratympanic injection of gentarnycin was equally effective in stopping the drop attacks associated with Meniere’s syndrome.
Dr Baloh is supported by NIH grant DC00097.
References 1. Tumarkin A. The otolithic catastrophe: a new syndrome. Br Med J 1936;1:175-177 2. Black JX,Effron MZ, Burns DS. Diagnosis and management of drop attacks of vestibular origin: Tumarlun’s otolithic crises. J Otolaryngol Head Neck Surg 1982;90:256-262 3. Janzen VD, Russell RD. Conservative management of Tumarkin’s otolithic crises. J Otolaryngol, 1988;17:359-361 4. Baloh RW, Honrubia V. Clinical neurophysiology of the vestibular system. 2nd ed. Philadelphia: F.A. Davis, 1990 5. Schuknecht HF. Delayed endolymphatic hydrops. Ann Otol 1978;87:743-748 6. Kuhl W. Vestibular-cerebral syncopes. Dtsch Med Wochenschr 1980;105:41-42 7. Kubala MJ, Millikan CH. Diagnosis, pathogenesis and treatment of “drop attacks.” Arch Neurol 1964;11:107-113 8. Brandt T, Dieterich M, Fries W. Otolithic Tullio phenomenon paroxysmal ocular tilt reaction. Adv Ototypically presents rhinolaryngol 1988;42:153-156 9. Odkvist LN, Bergenius J. Drop attacks in Meniere’s disease. Acca Otolaryngol Suppl (Stockh) 1988;55:82-85
Electroencephalography Laboratory Diagnosis of Prolonged QT Interval Sidney M. Gospe, Jr, MD, PhD,”t and Andrew J. Gabor, MD, PhD’ Patients with prolongation of the Q T interval are at risk for significant neurological morbidity and mortality secondary to ventricular tachyarrhythmias. These patients frequently undergo electroencephalographic (EEG) examination to evaluate episodes of loss of consciousness, which may be associated with convulsions. Electrocardiogram recording as a part of the EEG is a simple and common practice, but analysis for possible Q T prolongation is not routinely performed by electroencephalographers. This is, in part, due to the fact that while calculation of the corrected QT interval is straight forward, a calculator is generally required. A nomogram that is presented simplifies determination of the corrected QT interval, facilitating diagnosis of prolongation of the QT interval in the EEG laboratory. Gospe SM Jr, Gabor AJ. Electroencephalography laboratory diagnosis of prolonged QT interval. Ann Neurol 1990;28:387-390 Two familial syndromes of QT prolongation have been well described { 1-31. Patients with either of these conditions are subject to ventricular dysrhythmias, which can lead to palpitations and syncope. Frequently these episodes are induced by exercise or excitement. Affected patients can present with seizures, and diagnosis may be delayed until an electrocardiogram (ECG) is obtained [4- lo]. If unrecognized, these disorders frequently lead to inappropriate treatment with anticonvulsants and to sudden death or severe neurological morbidity secondary to hypoxic ischemic brain injury. Prior to diagnosis, many patients with these conditions undergo electroencephalographic (EEG) examinations as part of an evaluation for syncope or seizures. During a routine EEG examination, ECG activity is frequently recorded for a portion of the study. We previously reported on two siblings with the autosomal dominant form of hereditary QT prolongation (Romano-Ward syndrome) for whom EEG examinations performed several years prior to the actual diagnosis contained ECG data documenting the abnormalFrom the Departments of *Neurology and ?Pediatrics, School of Medicine, University of California, Davis, Davis, CA. Received Jan 19, 1990, and in revised form Mar 27. Accepted for publication Mar 30, 1990. Address correspondence to Dr Gospe, Department of Neurology, University of California, Davis Medical Center, 2315 Stockton Blvd., Sacramento, CA 95817.
Copyright 0 1990 by the American Neurological Association
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