Incudostapedial Joint Research Articles

The use of tragal cartilage in ossicular reconstruction

Readily available tragal cartilage has been found to be a very beneficial autogenous graft source for construction of prostheses to correct those defects in the ossicular chain that frequently occur when the incudostapedial joint is destroyed by middle ear pathology, particularly by the retraction of the posterior, superior quadrant of the tympanic membrane against and/or around the incudostapedial connection. This is true whether there be only erosion of the incus just at the joint, or whether there is erosion of the entire long process of the incus together with the superstructure of the stapes. The various types of deformity and the particular tragal cartilage prosthesis tailored for each deformity, and designed for maximum gain in hearing, are presented together with representative pre- and postoperative audiograms for the variety of types.

Tympanoplasty in blast-induced perforation.

Tympanoplasties were performed on 107 blast-induced tympanic membrane ruptures. An air-bone gap of less than 10 dB, or a speech reception threshold of less than 30 dB was obtained on 80.6% of cases. An intact tympanic membrane was achieved in 86.9% of cases. The most frequent form of ossicular abnormality was disruption of the incudomalleolar joint and adhesion of the malleus tip to the promontory. This occurred in approximately 25% of cases. Incudostapedial joint abnormality occurred in 8.4% of cases. Medial placement of graft material had both lower graft failure rate and better hearing result than lateral placement.

INCUDOSTAPEDIAL JOINT DISARTICULATION-Reply

In response to the letter of Erich Kuschke, ChM, from Bellville, South Africa, regarding our article concerning a method for surgical treatment of incudostapedial joint disarticulation, I have recently read the article Conductive Deafness Following Head Injury—Repair of a Dislocated Incudostapedial Joint by Wiring published in the South African Medical Journal in January 1969 by Dr. Kuschke. No doubt this article describes a method similar to ours published in theArchivesin February 1972. The case we described was performed in February 1968. Having felt that we developed this technique on our own, we first submitted the article for publication in early 1969 in good faith and entirely unaware of Dr. Kuschke's published work. We did review the literature prior to the writing of the article; however, at the time we were writing, Dr. Kuschke's article had not yet appeared and also unfortunately, neither of us nor our local medical

Incudostapedial joint disarticulation.

To the Editor .—I was greatly interested in the article entitled Incudostapedial Joint Disarticulation by Holler et al (95:182-184, 1972). I agree with it whole-heartedly, but would like to draw your attention to two case reports made by me three years previously in the South African Medical Journal (43:42,1969). As my report was in a journal not commonly read by otolaryngologic surgeons in the United States, I can easily understand why this has not come to your or the authors' notice. I suppose they may also claim originality; but it is not a new method, being exactly what I described three years ago. I have since used it with complete success in two further cases.

Fibrous ankylosis of the incudostapedial joint.

During the last six years 30 cases of fibrous ankylosis of the incudostapedial joint have been found. At operation tests of ossicular mobility gave evidence of rigidity of the ankylosed joint in all 30 cases and, therefore, the ossicular chain was preserved. A follow-up proved that this policy gave quite satisfactory results: in 25 cases the airbone gap was less than 25 dB, and in the majority of them it was almost closed. Only in two cases should unsatisfactory hearing results be ascribed to defective functioning of the preserved chain. Thus, preservation of an ossicular chain with fibrous ankylosis of the incudostapedial joint seems to be indicated if the intraoperative tests point to a rigid connection of the incus with the stapes.

Dynamics of implants for the human middle ear

Within the overall hearing process the middle ear has an important function: A sound wave conveyed by the external ear canal to the ear drum is transmitted to the oval window as mechanical vibration by the ossicular chain. For the investigation of the dynamical behavior a mathematical representation with qualified models is necessary. From the mechanical point of view there are some important diseases in the middle ear: Loss, rupture or fixation of ligaments, loss of iucudo-malleal joint or incudo-stapedial joint, stiffening of incudo-stapedial joint (ankylosis), and fixation of the stapes (otosclerosis). The aims of this work are the generation of mechanical models with physical parameters like real masses, stiffness and dampings for describing normal, pathological and reconstructed ears, for the prediction of the effects of middle ear surgery and for developing passive and active hearing aids.

Modification of the technique of repositioning the posterior crus in otosclerosis.

PRESENTLY, otologic surgeons strive to use unaltered parts of the stapes in stapedioplasty in view of the potential dangers to the inner ear which can arise when the replacement for the stapes is made of artificial materials and the occurrence of a large number of complications. Techniques well known in the literature of partial stapedectomy and stapedioplasty by means of interposition of a stapedial crus are basically alike. These techniques utilize the posterior crus (with or without the adjoining section of the foot plate) following fracture or removal of either the entire foot plate or only the anterior crus. The entire oval window or its partial opening is covered with a piece of vein or with a resorbable gelatin sponge. In the presence of a violation of the integrity of the incudostapedial articulation some surgeons fortify it with a vein. While performing these operations, many surgeons seek to preserve, undamaged,

Application of the Mössbauer method to ear vibrations.

The Mössbauer effect has been applied to the measurements of phase and amplitude relations in the vibrations of the guinea pig ear in vivo induced by sound in the normal hearing range. Measurements were made on the umbo and on the incudostapedial joint. The relative phase was near zero throughout the measured frequency range of 250 cps-9 kc/sec, and the lever-ratio was nearly constant at a value of about 2.0.

Congenital anomalies of the ossicles without deformities of the external ear

Anomaly of the ossicles is frequently seen in a patient with congenital anomalies of the head or face, such as congenital obstruction of the external ear canal, Treacher Collins syndrome or cephalopathy. Congenital anomaly of the ossicles however is not a rare occurrence even in a patient without anomalies of the head or face.Here, we would present our own experience with six cases of congenital anomalies of the ossicles and with one case of congenital deformity of the round window. The patients with anomalies of the ossicles had non-progressive hearing impairment of purely conductive type, except for one case which had been accompanied by otosclerotic changes and had a bone conduction loss.Case 1. 24-year-old male.An exploratory operation of the left ear had revealed that there were a bony fusion of the short process of incus with the horizontal semicircular canal and a dislocation of the long process of incus, resulting in separation of the incudostapedial joint. The bony bridge was removed and the separated joint was reconstructed by means of a polyethylene tube strut. The acoustic gain was 42db.Case 2. 41-year-old male.Congenital anomaly of the left middle ear was found to be a bony fusion of the short process of incus with the horizontal semicircular canal. The bony bridge was removed, resulting in a hearing improvement. But his hearing became wor se after several months, probably due to recurrence of ankylosis.Case 3. 21-year-old male (left ear)Case 4. 24-year-old male (left ear)Both cases had congenital separation of the incudostapedial joints, due to maldevelopment of the long process of incus. These separated joints were reconstructed by means of a polyethylene tube strut. Hearing improvement were considerable in both cases.Case 5. 31-year-old male.Congenital absence of the head and crus of the stapes was found in his left ear. The foot-plate was movable. A polyethylene tube collumela was introduced between the long process of incus and the foot-plate. Hearing gain was about 30db.Case 6. 38-year-old female.The patient had otosclerosis in both ears. Congeaital separation of the incudostapedial joint was seen in the left ear. Following a stapes mobilization operation, the ossicular chain was reconstructed by means of a polyethylene tube strut. Hearing gain was considerable.Case 7. 25-year-old female (right ear).The round window niche was remarkably narrow.

Experimental Studies on the Mechanism of Sound Couduction of the Ossicular Chain

In order to make clear the mechanism of sound couduction of the ossicular system, the author investigated the alteration of the cochlear potentials after the partial adhesion at different points of the ossicular chain of many cats by the use of tissue adhesives (α-cyano-acrylate-monomer=Aron Alpha).The following results were obtained:(1) After adhesion of the manubrium of the malleus to the eardrum, there appeared the reduction in C. M. response even to 15-20dB in the range from 0.2 to 2kcps.(2) Stiffness of incudo-malleolar joint resulted in no reduction in C. M. response. But adhesion of the incudo-malleolar joint to the epitympanum led to a loss of 10-20dB in the range from 0.2 to 1kcps.(3) Adhesion of the incudo-stapedial joint improved the C. M. response up to 5dB in the range from 0.2 to 1kcps while there was no reduction in the higher frequency range.(4) After stapedial fixation, a loss in the low to middle frequency range, was larger than high frequency range and the notchs were observed in 0.2 and 1kcps. It is persumed that the notch of 0.2kcps is largely due to the inner impedance while that of 1kcps indicates the resonant point of the stapes.(5) Stiffness of the all ossicular chain by the partial adhesion at several different points showed that the resonant point of the all ossicular system is centered around 1kcps, and the loss of C. M. response is about 40dB in the low range, about 50dB in the middle range, and about 20dB in the higher frequency range.

Importance of incudostapedial joint and long process of incus

Importance of long process of incus and the incudostapedial joint is emphasized and blood supply of the long process should not be neglected in our zeal of doing stapedectomy while in tympanoplasty its absence presents the difficulty.

Stapedius Muscle Reflex After Interposition Operations

The function of stapedius reflex was investigated by rising the indirect method of measuring acoustic impedance when the contra-lateral ear was stimulated with pure tones. The material consists of 12 patients and 14 operated ears. In all the cases an interposition was made and one or both of the crura of the stapes were placed on the fascia covering the window without opening the incudo-stapedial joint and without cutting the stapedius-tendon. A positive reflex was obtained for eight cars, at least at some frequencies. Totally negative results were obtained in six cases. The results show that a positive stapedius reflex is often possible after an otosclerosis operation in which the incudo-stapedial joint and the stapedius-tendon are left intact. The reflex may be negative even if hearing tests show that the ossicles are mobile and normal in their function.The results also indicate that the immobility of the incudo-stapedial joint and the way the stapes is fixed to the oval window are factors that influenc...

The blood supply of the incudostapedial joint and the lenticular process.

The blood supply of the incudostapedial joint and the lenticular process.

A case of traumatic disruption of the incudo-stapedial joint.

A case of traumatic disruption of the incudo-stapedial joint.

Prosthetic articulations in stapes surgery.

In the revived era of stapes mobilization, the first group of approaches following Rosen's^1-3leadership involved indirect force applications transmitted to the ankylosed area to liberate the fixed stapes from its pathologic attachments and remobilize it. Thus, force was applied either to the incus, to the incudostapedial articulation, to the neck, or to the crura, utilizing various shaped picks and blunt instruments. In these early attempts, many successful results were obtained. This indirect type of operation is still in use throughout the world, with a yield of approximately 30% successful mobilizations. In the other 70% of cases, the indirect approach usually resulted in either the disruption of the incudostapedial joint or crural fracture, so that the force application never quite reached the crucial ankylosed area and remobilization was not achieved. As experience in this approach accumulated, it became obvious that it was not desirable to sacrifice the ossicular chain

Basic studies of the restoration of sound conducting system by tympanoplasty

Part 1. On the Conduction Capacity of the ColumellaAfter extracting the temporal bone of cats the author gave sound stimuli to this temporal bone through the external auditory canal and measured the vibration amplitude of the labyrinthine side by means of a capacitative probe and determined the conduction capacity of the sound conducting system at 250, 500, 1, 000 and 2, 000cps when the lever function of the ossicular chain is obliterated. The results are as follows:1. When the malleus and incus are removed from the normal sound conducting system, the sound conduction capactiy decreases about 28db in average.2. After the removal of the malleus and incus from the normal sound conducting system:a) When the portion between the capitulum of the stapes and the part of the tympanic membrane corresponding to the short process, is communicated with an artificial columella, the sound conduction capacity increases about 21db as compared with that in the item 1, and shows a decrease in the capacity by 7db in average as compared with the normal.b) When the central part of the tympanic membrane and the capitulum of the stapes are communicated with an artificial columella, the sound conduction capacity increases 16db in average as compared with that of the iteml.c) when the part of the tympanic membrane corresponding to the umbo and the capitulum of the stapes are communicated with an artificial columella, there can be observed an increase in the sound conduction capacity by about 14db as compared with that of the item 1, showing a decrease of about 14db as compared with the normal.d) When the skin graft is placed on the capitulum of the stapes as to touch each other in the case where the tympanic membrane was deliberately removed, the sound conduction capacity decreases about 10db in average as compared with the normal.3. The weight ratio of the artifcial columellas used in the model experiments is 1:3:5, and it seems that the lighter is the weight of the columella the better the restoration of the sound conduction.4. It has been found that in the application of artificial columella the decrease in the sound conduction capacity is more marked in the high tone range than in the low tone range.Part 2. Sound Conduction Capacity in Various Sound Conducting Systems by ManipulationWith the temporal bone removed from human sudjects, sound stimuli were given through the external auditory canal, and the vibration amplitude of the labyrinthine side was measured with a capacitative probe in order to estimate the efficacy of various sound pathways reconstructed by tympa noplasty. The following are the results:1. When the antrum is blocked, the sound conduction capacity is raised by about 5 db in the range below 1, 000cps, and is decreased by about 5 db in the range of 2, 000 cps.2. In the attic, when there is an adhesion between the skin graft on onehand, the head of malleus and the incus on the other, the sound conduction capacity is diminished and it is especially marked in the range above 1, 000cps, 3. In order to maintain a better sound conduction capacity after tympanoplasty, it is desirable to leave a bony bridge and/or a vertical bony bridge to prevent the skin graft from adhesion.4. When the long process of the incus and the stapes are connected with a polyethylene tube after separating the incudostapedial joint, the decrease in sound conduction capacity proves to be only about 2db in average.

Report on 130 cases of Stapes Mobilisation Operation

130 cases of Stapes Mobilisation Operation have been reported. Of these only 61 cases of different groups reported for post-operative assessment of results, in which 41 casesi.e., 67% showed slight improvement upto 30 Db. and 8 casesi.e., 13.3% showed significant improvement upto 45 Db. 11 casesi.e., 18% showed no improvement whereas only one casei.e., 1.7% showed slight deterioration. Peculiarly enough this case belonged to group ‘A’ and it had no post-operative complication and its progress was uneventful. I am at a loss to account for this deterioration. Unfortunately this patient did not report again for re-operation of the same ear, after some time. Of the no improvement group consisting of 11 cases, 4 had otitis externa and 1 otitis media in the post-operative period, 3 had dislocation of the Incudo Stapedial joint, 2 had fracture crura, one uncomplicated ‘no improvement’ case still presents the problem for the solution of no improvement.

STUDY ON PROBLEMS IN GELLES TEST

When the cases of otosclerosis, chronic adhesive otitis media and dislocation of the incudo- sta pedial joint are examined using conventional Gelle's test, the results are always negative, and the test is of no use for the differential diagnosis of these diseases.Therefore, for the purpose of differential diagnosis, first, being confirmed that Gelle's test by bone conduction was negative, the qualitative test by air conduction was a pneumophon with applied to these cases.The following results were obtained:1.Otosclerosis:The application of positive or negative pressure to the external auditory canal generally reduces the loudness of air-conducted tones. 2.Otitis media chronica adhesiva:When a negative pressure is applied to the external auditory canal, air-conducted tone decreases in loudness like in the case of otosclerosis but the application of positive pressure to the auditory canal causes no decrease in the loudness of air-conducted tone. 3.Dislocation of the incudostapedial joint:When the negative pressure up to - 10mmHg is applied to external auditory canal air-conducted tone increases in loudness, but when the negative pressure up to -30_??_-40mmHg is applied, the air-conducted tone decreases in loudness.The application of positive pressure causes a decrease in the loudness of air-conducted tone just as in the case of otosclerosis. Summarizing the above, it seems that the differential diagnosis of those diseases negative to Gelle's test is made to some extent with the use of the qualitative test by air conduction with a pneumophon.

Stapes mobilization; problems and perspectives.

At this stage of stapes mobilization surgery, it appears appropriate to evaluate some existing problems, and to consider some perspectives. The two problems to be presented are the following: The footplate approach Delayed postoperative threshold shift. A perspective which merits discussion is the question of combined myringoplasty and stapes mobilization in otosclerotics with tympanic deformities due to coexistent adhesive otitis. I. The Footplate Approach There has been a significant evolution in the modus operandi of the surgical technique of stapes mobilization since the first publication of Rosen, 1 when he advised mobilization via the stapedial neck with a specially curved instrument. Shortly thereafter, others 2-3 suggested force application through the lenticular process of the incus, through the capitulum of the stapes, and other modifications in the region of the incudostapedial joint. It was quite logical that initial attempts to mobilize the ankylosed stapedial footplate should begin at the

THE EXPERIMENTAL STUDY ON THE ACOUSTIC REFLEX CONTRACTION OF THE STAPEDIUS MUSCLE

The acoustic reflex contraction of the stapedius muscle and its influence on the incudo-stapedial joint were studied by means of the electromyogram of the stapedius muscle and condenser method.The following results were obtained: 1) The latent period of the acoustic reflex contraction of the stapedius muscle was 3.44 msec.2) The acoustic reflex contraction of the stapedius muscle was not only influenced by the intensity but also by the frequency of the stimulating tone.The electromyogram of the stapedius muscle was obtained at about 50-16, 000 cps.3) On the stapedius muscle, adaptation phenomenon was observed on the electromyogram; this phenomenon was similar to that of the tensor muscle and the auricular muscle.4) The threshold of the acoustic reflex contraction was about 20_??_100 db on the stapedius muscle and always lower than that of the tensor muscle.5) The displacement of the stapes and the deformation of the incudo-stapedial joint during the reflex contraction' of the stapedius muscle were observed throuth the microscope