Inverted caloric nystagmus of perforated ears upon air caloric stimulation

It is well known that inverted caloric nystagmus is seen during air caloric testing in cases of chronic otitis media. The mechanism of inversion and its clinical significance are discussed here. Temperature changes in the tympanic cavity and external ear canal were measured with a microthermister and a digital tester in seventeen ears with tympanic membrane perforation, during bithermal air caloric testing. The tympanic cavity mucosa was cooled by hot stimulation because of the evaporation of heat. When the perforation was closed or humidified air was used, the tympanic cavity mucosa was not cooled by hot stimulation and the inverted caloric nystagmus changed to a normal response. Inverted caloric nystagmus occurred in 30.4% of 335 ears affected by chronic otitis media with perforation. Inverted caloric nystagmus occurred in 90 ears with hot stimulation and in 12 ears with cold stimulation. Inverted caloric nystagmus turned to normal response after myringoplasty in all of 10 ears. The cooling effect caused by evaporation of water from the moist middle ear mucosa during dry air blowing and direct thermal conduction to the vestibulum through a perforation of the ear drum and inversion of the endolymphatic convection seemed to cause the inversion.     

鼓膜穿孔眩晕者的冷热气试验结果分析

目的：分析冷热气刺激下鼓膜穿孔患者的试验结果特点,探讨鼓膜穿孔者冷热气试验的可行性。方法：慢性中耳炎鼓膜穿孔伴眩晕的患者43例（49耳）,行双耳冷热气试验,观测眼震特点、慢相角速度（SPV）和眼震不对称比（UW）。结果：穿孔耳冷热气刺激诱发眼震呈现4种类型：①增强型：穿孔耳诱发性眼震SPV增强并超过正常范围,或强于非穿孔耳、UW＞15％者15例（17耳）;②“正常型”：穿孔、非穿孔耳眼震SPV均在正常范围,UW〈15％者7例;③减弱型：穿孔耳眼震SPV弱于非穿孔耳,UW〉15％者9例;④反向型：非穿孔耳冷热气刺激眼震正常,穿孔耳热气刺激眼震反向者12例（14耳）。反向型眼震均出现在近期慢性中耳炎复发、鼓膜穿孔且有渗出或潮湿者;其余类型均为慢性中耳炎静止期患者。结论：对于穿孔耳,冷热气成为强刺激,半规管功能正常时诱发的眼震强于非穿孔耳;穿孔耳半规管功能不同程度减弱时,诱发眼震可为正常或减弱反应;活动期的中耳炎患者,穿孔耳热气刺激可转化为冷刺激效应,诱发出反向眼震;冷热气试验可用于鼓膜穿孔伴眩晕患者的前庭功能评定。     

Symposium: Value and cost analysis of recent ear tests. Air caloric testing in otitis media (preliminary studies)

On certain occasions it becomes inportant to evaluate vestibular function in a patient with otitis media. The potential application of the air caloric test in evaluating such patients was examined. Patients with unilateral otitis media before and after surgery were studied to answer certain clinical questions. More questions were raised than answers provided. The preliminary conclusions from this study are:

• 1 Patients with tympanostomy tubes or small perforation of one ear may show a caloric response in the perforated ear equal to that of the intact ear.
• 2 Patients with a large tympanic membrane perforation on one side may show hyperactive caloric responses on the perforated side.
• 3 Patients with a moist ear may show inverted horizontal nystagmus to warm air caloric testing. This applies to patients with a large perforation or mastoidectomy cavity.
• 4 Patients with a dry open mastoid or fenestration cavity are likely to show a hyperactive caloric response on the side of previous surgery, accompanied by vegetative symptoms. This size of the cavity appears to be less important than the presence of the cavity per se.
• 5 Patients may be safely tested in the early postoperative period.

     

Caloric stimulation with near infrared radiation does not induce paradoxical nystagmus

Near infrared radiation can be used for warm stimulation in caloric irrigation of the equilibrium organ. Aim of this study was to determine whether near infrared radiation offers effective stimulation of the vestibular organ, whether it is well tolerated by the patients and especially whether it is a viable alternative to warm air stimulation in patients with defects of the tympanic membrane and radical mastoid cavities. Patients with perforations of the tympanic membrane (n = 15) and with radical mastoid cavities (n = 13) were tested both with near infrared radiation and warm dry air. A caloric-induced nystagmus could be seen equally effectively and rapidly in all patients. Contrary to stimulation with warm dry air, no paradoxical nystagmus was observed following caloric irrigation with a warm stimulus (near infrared radiation). Results of a questionnaire showed excellent patient acceptance of near infrared stimulation with no arousal effects or unpleasant feeling. In conclusion, near infrared radiation proved to be an alternative method of caloric irrigation to warm dry air in patients with tympanic membrane defects and radical mastoid cavities. Near infrared radiation is pleasant, quick, contact free, sterile and quiet. With this method an effective caloric warm stimulus is available. If near infrared radiation is used for caloric stimulus no evaporative heat loss occurs.     

Near infrared stimulation of the equilibrium organ--first clinical experiences

BACKGROUND: A new method for the stimulation of the organ of equilibrium by means of a broad-scale and monochromatic near infrared emission was developed. This method should be examined within the framework of a pilot study, evaluated and its clinical possible applications examined. PATIENTS AND METHODS: Healthy probands (n = 15), patients with a radical cave of the ear (n = 5), patients with a defect of the tympanic membrane (n = 5) and spontaneous nystagmus (n = 5) were examined. In healthy probands an irritation with broad-scale as well as monochromatic near infrared (NIR) was performed and compared with a water irrigation (44 degrees, 50 ml in 30 seconds). The subjective, local feelings during the application and the appearance of giddiness according to irritation were recorded and the nystagmus was registered by means of videonystagmography. In patients with radical cave of the ear and tympanic membrane defects, a broad-scale NIR-irritation before a comparative irritation with warm air (44 degrees) was performed exclusively. RESULTS: In all healthy probands, a nystagmus reaction could be seen with broad-scale and monochromatic NIR. Compared to the hot water irritation slow phase velocity (SPV) was decreased however registrable by means of Frenzel glasses and electronystagmography during the culmination stage. In patients with radical cave (n = 4) and tympanic membrane defects (n = 3) showing paradoxical nystagmus reaction during hot air irritation, a nystagmus to the site of stimulation resulted by means of light calorisation. In patients with a spontaneous nystagmus an attenuation (n = 1) or inversion (n = 2) could be achieved by NIR-radiation. CONCLUSIONS: The method of the NIR-radiation is suitable in clinical practice for the caloric test proofing warm reaction. Vaporization cold does not occur. The application of heat charm is better proportionable and steerable than during air irritation. The procedure is sterile, noiseless and non-contact. Difficulties in interpretation of results of vestibular tests because of evaporation coldness do not occur.     

Experimental study of nystagmus induced by injecting various solutions into the middle ear cavity

Injecting of various solutions into the middle ear cavity of cats and rabbits provoked certain characteristic types of nystagmus which resembled caloric nystagmus or clinical cases of peripheral vestibular disorders. Solutions with different degrees of specific gravity, osmotic effect and ion composition were used in this study. Direction-changing positional nystagmus, irritative nystagmus, and paralytic nystagmus were elicited according to the physical or chemical properties of each solution. Histological findings showed mild changes in the perilymphatic space and/or in the endolymphatic space in the period with some characteristic types of nystagmus. Infiltration of the substances into the inner ear fluids from the middle ear cavity via a round window membrane were probably responsible for these types of nystagmus.     

Vestibulo-ocular reflex (VOR) preserved in bilateral severe vestibular malformations with internal auditory canal stenosis

A 60-year-old woman, who has suffered from bilateral deafness throughout her life, visited our outpatient clinic. Computed tomography (CT) revealed inner ear malformations, which comprise cochlear aplasia with hypoplastic vestibule in the right ear and a common cavity in the left ear, and narrow internal auditory canals. We performed electronystagmography with caloric stimulation and stimulation of earth-vertical axis rotation (EVAR) or off-vertical axis rotation (OVAR), and studied vestibular evoked myogenic potentials (VEMPs) and vestibular ocular reflex (VOR). Slight horizontal nystagmus was induced by the stimulation of EVAR but not by caloric stimulation. Slight vertical nystagmus was observed during OVAR, whereas the VEMP test elicited no response. The result of horizontal or vertical VOR performed in the dark was almost normal. These findings suggest that VOR can be acquired even with severe malformation of the inner ear whose labyrinthine functions markedly reduce bilaterally until nystagmus is slightly induced by rotation stimulation.     

Vestibulo-ocular reflex (VOR) preserved in bilateral severe vestibular malformations with internal auditory canal stenosis

A 60-year-old woman, who has suffered from bilateral deafness throughout her life, visited our outpatient clinic. Computed tomography (CT) revealed inner ear malformations, which comprise cochlear aplasia with hypoplastic vestibule in the right ear and a common cavity in the left ear, and narrow internal auditory canals. We performed electronystagmography with caloric stimulation and stimulation of earth-vertical axis rotation (EVAR) or off-vertical axis rotation (OVAR), and studied vestibular evoked myogenic potentials (VEMPs) and vestibular ocular reflex (VOR). Slight horizontal nystagmus was induced by the stimulation of EVAR but not by caloric stimulation. Slight vertical nystagmus was observed during OVAR, whereas the VEMP test elicited no response. The result of horizontal or vertical VOR performed in the dark was almost normal. These findings suggest that VOR can be acquired even with severe malformation of the inner ear whose labyrinthine functions markedly reduce bilaterally until nystagmus is slightly induced by rotation stimulation.     

鼓膜局部病变切除治疗咽鼓管球囊扩张术后局限性鼓膜膨胀不全

目的探讨局部病变鼓膜切除治疗咽鼓管球囊扩张术后局限性鼓膜膨胀不全的方法与疗效。方法收集分泌性中耳炎伴局限性鼓膜膨胀不全患者16例（16耳）,其中男9例,女7例,年龄24～48岁,所有患者既往曾行药物治疗、鼓膜穿刺和（或）置管,并行咽鼓管球囊扩张术（balloon eustachian tuboplasty, BET）术后6个月,仍有分泌性中耳炎伴局部鼓膜膨胀不全,均在耳内镜下行局部病变鼓膜切除术。随访记录鼓膜形态,耳闷塞感情况,气－骨导差,随访时间6个月。结果局限鼓膜切除术后1个月,16耳鼓膜均愈合,部分切除区域稍菲薄,未见内陷穿孔。耳闷塞感评分明显改善,由术前的（6.4±1.3）分下降为（1.2±0.8）分;气－骨导差较术前明显改善,由术前的（13.2±4.3） dB下降为术后的（4.6±3.2） dB,经比较差异均有统计学意义（P<0.05）,耳闷塞感评分及气－骨导差术后1个月与6个月比较无统计学意义（P＞0.05）。临床表现术后6个月无反复。结论对于咽鼓管球囊扩张术后仍有局限性鼓膜膨胀不全的患者,将局部病变鼓膜切除是一种微创、有效的治疗方法。     

Selective stimulation of the equilibrium organ using monochromatic near infrared

BACKGROUND: The aim of this study was, to establish, if a selective thermal warm-stimulation using monochromatic near infrared radiation (NIR) in healthy persons, patients with chronic otitis media (chronic mucosal inflammation) and after radical surgery of one ear shows quantitative or qualitative changes of the nystagmus reaction. PATIENTS AND METHODS: Healthy persons (n = 3), patients with a large central defect of the tympanic membrane (n = 5) and after radical ear surgery (n = 6) were examined. In healthy persons a stimulation with monochromatic NIR (lambda = 980 nm) of several areals of the external auditory canal was performed. In patients with large defects of the tympanic membrane the promontorium was stimulated. In patients with a radical cave of the ear a selective NIR-stimulation of the region of the vertical and the anterior semicircular canal was performed. The horizontal semicircular canal was visible as a landmark. Registration of the nystagmus was performed by means of videonystagmography. RESULTS: In healthy persons the mean slow phase velocity of the nystagmus depended on the stimulated region. But there was no qualitative change of three dimensional eye movement. Stimulation of the promontorium showed a strong directional horizontal nystagmus. In patients with a radical cave the stimulation of the regions of the three semicircular canals showed a qualitative difference in three dimensional eye movement. NIR-stimulation showed in all cases a nystagmus into the stimulated ear. CONCLUSIONS: The method of monochromatic near infrared stimulation can be used for selective stimulation of several regions of the external auditory canal, the promontorium and the regions of the semicircular canals in a radical cave of the ear as well as to prove the warm reaction of the equilibrium organ. A specific nystagmus after stimulation of the semicircular canal-region in a radical cave of the ear could be an indication for a normal semicircular canal function.     

The influence of middle ear pressure on the vestibular nerve activity in cats

The influence of middle ear pressure on the vestibular nerve activities was investigated in anesthetized cats. The vestibular nerve activities were recorded intraaxonally and positive or negative pressure was applied to the middle ear cavity through a tympanic membrane perforation. The firing of vestibular nerve fibers, especially the regular type nerve that responded to horizontal semicircular canal stimulation, increased with positive pressure and decreased with negative pressure. Most vestibular nerves that responded to anterior or posterior semicircular canal stimulation were not influenced by changes in the middle ear pressure. These results indicate that middle ear pressure load is transmitted to the vestibular end organs and then to vestibular nerve.     

Tympanoplasty with adipose tissue

BACKGROUND: Among other materials it is also possible to use autologous fat tissue for closing tympanic membrane perforations. In this study we have evaluated 44 consecutive myringoplasties with adipose tissue performed between 1999 and 2001. MATERIAL AND METHOD: The indications were residual microperforations following tympanoplasty with temporalis fascia or tympanic membrane perforations due to trauma or chronic otitis media simplex. Myringoplasty with fat tissue was performed as an outpatient procedure and took about 15 minutes. The adipose tissue was harvested from the posterior side of the ear lobe in local anaesthesia. After refreshing the borders of the tympanic membrane perforation with a micro hook, the adipose tissue was positioned into the perforation by using a handheld or fixed ear speculum. The graft was covered with a silk strip soaked with Garamycine ointment. In bigger perforations a bed of gelfoam was put into the tympanic cavity in order to avoid adhesions between the graft and the promontorium. RESULTS: A permanent healing of the tympanic membrane was achieved in 40 (91 %) out of the 44 patients. In 21 patients hearing improved between 5 -10 dB. Surgical complications did not occur. CONCLUSIONS: Our results indicate that transcanal myringoplasty with adipose tissue is a simple and minimally invasive method for closing small to medium sized tympanic membrane perforations.     

Acute otitis media develops in the rat after intranasal challenge of Streptococcus pneumoniae

OBJECTIVES/HYPOTHESIS: The rat is a frequently used animal model for middle ear research. To date, acute otitis media (AOM) has been evoked after instillation of bacteria directly into the middle ear cavity or after traumatizing the tympanic membrane. The purpose of the study was to examine whether, with an intact tympanic membrane and middle ear cavity, intranasally deposited bacteria cause AOM and how tympanic membrane stimulation influences this procedure. STUDY DESIGN: In vivo, murine model. METHODS: In a rat model, Streptococcus pneumoniae, type 3, was intranasally inoculated for 5 consecutive days. The tympanic membrane was treated with saline or with compound 48/80 or was left untreated. The development of AOM was evaluated by otomicroscopy, light microscopy, and middle ear culture. RESULTS: Ninety percent of the ears developed AOM. However, when the tympanic membranes were treated with saline or compound 48/80, only 40% and 57%, respectively, developed AOM. In all, 23 of 40 ears developed AOM and 20 ears showed growth of bacteria. CONCLUSION: Repeated intranasal deposition of S. pneumoniae, type 3, causes AOM in the rat. The development of AOM can be influenced by tympanic membrane stimulation.     

Caloric nystagmus in three dimensions under otolithic control in rhesus monkeys. A preliminary report

The caloric nystagmus of rhesus monkeys in the 'optimum' supine or prone position was recorded three-dimensionally using magnetic search coils. The horizontal component of the nystagmus was in the direction expected from the convection flow theory of Bárány. The torsional component changed its direction according to the side of caloric stimulation independent of head position with regard to gravity, i.e., counterclockwise nystagmus by right ear stimulation and clockwise nystagmus by left ear stimulation both in the supine or in the prone positions. The direction of the vertical component depended upon the head position and not upon the side of stimulation, i.e., up-beating nystagmus in the supine position and down-beating nystagmus in the prone position. The durations and the contours of slow phase velocity of the horizontal, vertical and torsional components were different from each other. The origins of the first phase of caloric nystagmus in three dimensions may be explained by activation of all the three semicircular canals. As for the second phase of caloric nystagmus in the supine or in the prone position, the torsional component was comparatively strong and lasted the longest among the three components. The second phase of caloric nystagmus was markedly modified by head position with regard to gravity. These findings suggest that it is the otolithic organs that determine the moving plane of second phase caloric nystagmus.     

Effects of otic drops on chinchilla tympanic membrane

Experimental studies have shown that if antibiotic otic drops reach the middle ear cavity they produce severe inflammation. However, the effects of these preparations on the tympanic membrane have not been thoroughly investigated. This study was designed to assess morphological changes in the chinchilla tympanic membrane two to 21 days after a single 0.2-mL application of an antibiotic otic preparation (Cortisporin Otic Suspension) to the middle ear cavity. At two days, the epidermal and the mucosal layers were destroyed. By four days, reepithelialization had occurred and all layers of the tympanic membrane subsequently became markedly hyperplastic. Disruption of the fibrous layer, invasion of keratinizing epidermis to the medial surface, and perforation were observed at three weeks. These findings indicate that tympanic membrane damage is a potentially significant aspect of the ototoxic properties of topical otic preparations.     

Determinants of Conductive Hearing Loss in Tympanic Membrane Perforation

ObjectivesTympanic membrane perforations are common, but there have been few studies of the factors determining the extent of the resulting conductive hearing loss. The aims of this study were to determine whether the size of tympanic membrane perforation, pneumatization of middle ear & mastoid cavity, and location of perforation were correlated with air-bone gap (ABG) of patients.MethodsForty-two patients who underwent tympanoplasty type I or myringoplasty were included and preoperative audiometry were analyzed. Digital image processing was applied in computed tomography for the estimation of middle ear & mastoid pneumatization volume and tympanic membrane photograph for the evaluation of perforation size and location.ResultsPreoperative mean ABG increased with perforation size (P=0.018), and correlated inversely with the middle ear & mastoid volume (P=0.005). However, perforations in anterior versus posterior locations showed no significant differences in mean ABG (P=0.924).ConclusionThe degree of conductive hearing loss resulting from a tympanic membrane perforation would be expected with the size of perforation and pneumatization of middle ear and mastoid.     

鼓膜外伤性穿孔自然修复的实验研究

目的研究大鼠鼓膜不同类型穿孔的自然修复过程，探讨鼓膜穿孔的修复机制。方法50只(100耳)大鼠，鼓膜完整，随机分5组，每组10只：①鼓膜紧张部中央2．5mm穿孔；②鼓膜紧张部中央1mm小穿孔；③紧张部后方边缘性穿孔；④紧张部3／4切除后铬酸烧灼锤骨柄；⑤松弛部中央1．5mm穿孔。光镜下观察鼓膜穿孔修复的组织改变。结果鼓膜紧张部穿孔后早期上皮退缩，锤骨柄和鼓环处上皮细胞增殖，上皮细胞的增生还出现在远离穿孔的正常鼓环区域。纤维层的增生晚于上皮层，上皮细胞的堆积首先封闭穿孔，不同大小穿孔的愈合时间差别无统计意义。单侧耳鼓膜穿孔，健侧耳鼓膜无明显变化。鼓膜后方边缘穿孔的上皮细胞未进入鼓室，破坏锤骨柄上皮后穿孔仍可愈合；松弛部穿孔愈合快，伴有紧张部鼓环上皮增殖。结论鼓膜紧张部的穿孔修复依赖于上皮细胞的移行，细胞的增殖中心位于鼓环和锤骨柄，中耳手术对鼓环和锤骨柄的保护有重要的意义。     

Perforation of the tympanic membrane and its effect on the real-ear-to-coupler difference acoustic transform function.

It is not always possible to undertake extensive real-ear measurements, especially in infants and young children. An alternative approach is to estimate the real-ear SPL by use of an acoustic transform function such as the real-ear-to-coupler difference (RECD). This may be used to estimate the real-ear sound pressure level (SPL) obtained from an insert transducer or a hearing instrument. The aim of the present study was to investigate the effects of tympanic membrane perforation on the RECD transform function. Subjects in the study comprised two groups of 12 individuals aged between nine and 65 years. One group of subjects had a tympanic membrane perforation and was recruited to the study before admission for myringoplasty. There was no evidence of middle ear pathology in the remaining subjects who comprised the control group. An RECD transform function for an insert transducer was measured on each subject using the standard clinical protocol on the Audioscan RM500 real-ear measurement system. There was a statistically significant difference between the two groups; mean RECD transform value of the perforation group was 9-12 dB lower than the corresponding value in the control group at audiometric frequencies below 1.5 kHz. This difference is probably due to the perforation acting as a vent and allowing low-frequency acoustic energy to escape into the middle ear cavity. Use of an average RECD transform function to estimate real-ear SPL in subjects with a perforation will overestimate the SPL reaching the tympanic membrane. As a result, the derived real-ear SPL obtained by use of either an insert transducer or a hearing instrument will be overestimated. This has implications for the selection and verification of a hearing instrument. The difference in the mean RECD transform function between the control group and subjects with a tympanic membrane perforation supports the use of individually measured RECD values wherever possible.     

Temporal bone histopathology in chronically infected ears with intact and perforated tympanic membranes.

Chronic suppurative otitis media has been clinically defined as a chronic discharge from the middle ear in the presence of a perforation of the tympanic membrane. However, irreversible tissue pathology in the middle ear or mastoid can occur behind an intact tympanic membrane. One hundred forty-four human temporal bones with chronic otitis media were divided into two groups: those with perforated (28) and those with nonperforated (116) tympanic membranes. The histopathological findings of their middle ears were compared. Granulation tissue in various degrees was the most prominent pathological feature. It was observed in 96% of temporal bones with perforation of the tympanic membrane, and in 97% of those without perforation. Also found were ossicular bony changes (96% with perforation; 90.5% without), middle ear effusion (93% with perforation; 89% without), cholesterol granuloma (21% with perforation; 12% without), cholesteatoma (36% with perforation; 4% without), and tympanosclerosis (43% with perforation; 20% without). This study shows that the histopathological changes of the middle ear are similar in temporal bones with and without perforation of the tympanic membrane. The clinician should, therefore, be aware that an intact tympanic membrane does not necessarily preclude the presence of gross pathological changes of the middle ear cleft.     

Postoperative result for tympanic membrane perforation

Ears with tympanic membrane perforation show a wide range of pathophysiology from simple perforation to mobility impairment of the ossicular chain complicated by sclerotic and/or inflammatory lesions of the middle ear. In surgery on such ears, we determine checkpoints and proceed based on the order of procedure. We studied postoperative results for 37 ears of patients undergoing tympanoplasty in the 3 years from June, 1996 to May, 1999. Lesions accountable for mobility impairment of the ossicular chain were confirmed and removed in the order of calcified tympanic membrane, tip of malleus handle, around the anterior tympanic spur, and epitympanum. Success in improving in hearing was 89.2% overall. Conductive impairment (air conduction-bone conduction gap) left on the patch test was found to differ with the site and range of tympanic and middle ear lesions. This can serve as a guide in preoperatively predicting the type of operation required.