Teflon Piston Prosthesis Research Articles

Evaluating hearing results in stapedotomy: Comparison of fluoroplastic Causse loop piston and Matrix prosthesis.

ObjectiveWe carried out this research to assess and compare post‐stapedotomy hearing results of Matrix titanium prosthesis with a Teflon piston prosthesis, specifically the fluoroplastic (Teflon) Causse loop piston prosthesis in patients who suffered from otosclerosis.MethodologyIn this retrospective study, Causse loop piston prosthesis was used in 81 ears, and the Matrix prosthesis was applied in 44 ears. For pairwise matching with Matrix prosthesis, 44 out of 81 Causse loop piston‐treated ears were selected based on preoperative audiometric data. Then, postoperative audiometric results of these two groups were compared. The main outcomes were pure tone audiometric results and air‐bone gap (ABG) closure before and after the surgery. Incidence of postoperative sensorineural hearing loss was also evaluated and compared between the two groups.ResultsThe results revealed no significant difference in improvement of speech reception threshold, mean air conduction, bone conduction gain, ABG closure, and incidence of postoperative sensorineural hearing loss at the frequencies of 0.5‐4 kHz between the two groups. However, performance of Matrix prosthesis was better in ABG closure at a frequency of 250 Hz.ConclusionHerein, similar postoperative improvement was achieved at the frequencies of 0.5‐4 kHz; nevertheless, Matrix provided better ABG closure at frequency of 250 Hz in short term.Level of Evidence4

Comparative study showing relevance of prosthesis diameter and hearing outcome in stapes surgery

<p class="abstract"><strong>Background:</strong> Otosclerosis presents as conductive hearing loss, stapedotomy is the treatment for otosclerosis, and different sizes of piston diameter are available for the procedure. Aims and objectives were to study and compare hearing improvement between the 0.4 and 0.6 mm sizes of teflon piston in stapedotomy.</p><p class="abstract"><strong>Methods:</strong> It was a prospective randomized controlled trial. Patients fulfilling inclusion criteria were subjected for small fenestra stapedotomy. Patients were divided into two groups after randomization into group A (with 0.4 mm piston diameter) and group B (with 0.6 mm piston diameter). The hearing outcome with standard audiological assessment was performed at one month and six months postoperatively. </p><p class="abstract"><strong>Results:</strong> Comparison of 1 month AB gap among the patients with 0.4 mm piston and 0.6 mm piston showed that there was no statistically significant difference among both the groups of patients (independent t test p value=0.699). Comparison of 6 month AB gap among the patients with 0.4 mm piston and 0.6 mm piston showed that there was no statistically significant difference among both the groups of patients (independent t test p value=0.54).</p><p class="abstract"><strong>Conclusions:</strong> There was no significant difference in hearing improvement among the individual methods (piston size 0.4 and 0.6) with each other both in 1 month post-operative and 6 month post-operative follow up. Hence, we conclude that there is no relevance of different diameter of teflon piston prosthesis (0.4 mm versus 0.6 mm) as far as hearing outcome is concerned.</p>

The impact of intra-operative factors in otosclerosis outcomes: retrospective study in a tertiary centre.

SUMMARYThe aim of the study was to assess results from a large cohort of patients undergoing otosclerosis surgery with respect to the impact of intra-operative variables on post-operative hearing function and complications. We enrolled 384 patients affected by otosclerosis who were subjected to stapes surgery between 2004 and 2013 at a single institution. Surgery was performed in all cases under local anaesthesia, using a manual perforator and/or microdrill. Teflon-piston prosthesis was used in all patients. Audiological data obtained preoperatively and at last follow-up examination (minimum 12 months) were compared. Statistical analysis was performed using the multiple regression model. Peripheral rim otosclerosis and diffuse otosclerosis were associated with better functional results compared to the obliterative pattern (p < 0.05). Mean post-operative Air-Bone Gap was significantly higher in the 0.4 mm, compared to 0.6 mm piston group at 0.5 kHz (p < 0.001) and 1 kHz (p < 0.02); in the stapedotomy group a statistically significant difference was found between 0.4 and 0.6 mm piston groups, in favour of the latter (p < 0.05). No differences were encountered in terms of average hearing threshold and complications. Intra-operative variables cannot be fully predictable and our data could help in stratification of the results and as a landmark for the surgeon’s decisions.

Hearing Outcome With the Use of Glass Ionomer Cement as an Alternative to Crimping in Stapedotomy.

To evaluate early hearing outcomes using glass ionomer cement to fix the Teflon piston prosthesis onto the long process of incus to minimize residual conductive hearing loss after stapedotomy. Original report of prospective randomized control study. Tertiary referral center. A total of 80 consecutive patients with otosclerosis were randomized into two groups. Group A is a control group in which 40 patients underwent small fenestra stapedotomy using the classic technique. Group B included 40 patients who were subjected to small fenestra stapedotomy with fixation of the incus-prosthesis junction with glass ionomer bone cement. Stapedotomy with the classical technique in group A and the alternative technique in group B. The audiometric results before and after surgery. Analysis of the results was performed using the paired t test to compare between pre and postoperative results. χ test was used to compare the results of the two groups. A p value less than 0.05 was considered significant from the statistical standpoint. Significant postoperative improvement of both pure-tone air conduction thresholds and air-bone gaps were reported in the two studied groups. The postoperative average residual air-bone gap and hearing gain were statistically significant in group B (p < 0.05) compared with group A. The use of glass ionomer bone cement in primary otosclerosis surgery using the aforementioned prosthesis and the surgical technique is of significant value in producing maximal closure of the air-bone gap and better audiological outcomes.

Stapes fixation accompanied with abnormal facial nerve pathway

The patient was a 52-year-old woman. She had been aware of her bilateral hearing loss since she was 20 years old. The hearing in her left ear started to deteriorate at the age of 49. Pure-tone audiometry showed a bilateral mixed hearing loss. The hearing levels for the right ear and the left ear were 52 dB and 68 dB, respectively. There were no remarkable findings in a computed tomography (CT) scan of the temporal bone. We suspected that she had otosclerosis, and an operation was performed on her left ear. When the incudostapedial joint (I-S joint) was exposed to investigate the movement of the stapes, a soft white band that ran under the superstructure of the stapes was noted. By using a nerve monitoring system, we confirmed that the white band was the bare facial nerve. The ossicular chain was normal, except for a malformed stape due to the facial nerve, and the footplate of the stapes was fixed. Therefore, she was diagnosed as having otosclerosis with an abnormal facial nerve pathway. The malformed superstructure of the stapes was removed carefully. When the ectopic facial nerve was shifted to anteroinferior side, the oval window could be seen. Stapedotomy using a Teflon piston prosthesis was performed with no complications.

Comparison of round-window membrane mechanics before and after experimental stapedotomy

Surgical intervention within the area of the middle ear always leads to alteration of conditions in its biomechanical system. This fact may provide an explanation for the lack of expected auditory outcome, although an apparently good anatomic outcome was obtained. In the case of stapedotomy, the majority of patients report lack of satisfactory results for frequencies above 2,000 Hz. The effect has not been experimentally investigated yet. This study, conducted in four human temporal bones, yielded a record of round-window membrane vibration amplitude and phase in the frequency function (400 Hz-10 kHz) at the sound intensity level of 90 dB administered to the external auditory canal in a physiologic condition and following implantation of a Teflon piston stapes prosthesis. The procedure of experimental stapedotomy was performed with the tympanic membrane preserved from the maximally dilated approach through the posterior tympanotomy. Stapes Teflon piston prosthesis implantation was found to cause approximately fivefold lower amplitude of round-window membrane vibrations compared to a physiologic situation for frequencies above 2 kHz in particular. After stapedotomy, with the use of a Teflon piston prosthesis, stimulation of inner ear structures diminishes, especially in higher frequencies.

Subiektywna śródoperacyjna poprawa słuchu u chorych po stapedotomiach w porównaniu z wynikiem kontrolnego badania słuchu w audiometrii tonalnej progowej

In otosclerosis patients the most common procedure followed at Otosurgical Dept. Medical University of Lodz is stapedotomy with insertion of teflon-piston prosthesis. When surgery is finished a whisper hearing test is done from the 1 meter distance for brief intraoperative hearing improvement assessment. There is a number of patient who report subjective intraoperative hearing improvement which is not confirmed by postoperative pure-tone audiometry (2-3rd post-op day). was the analysis of factors influencing stapedotomy (teflon-piston procedure) patients in which intraoperative hearing improvement was not confirmed by postoperative pure-tone audiometry. Retrospective analysis of postoperative hearing results in patients who underwent stapedotomy (teflon-piston operation) at the Otosurgical Dept. Medical University of Lodz from 2005 to 2009. The total number of 142 stapedotomies were analyzed. In 27 ears no hearing improvement was reported (19.1%). Among them 18 reported intraoperative hearing improvement not confirmed on postoperative pure-tone audiometry and 9 cases intraopertively reported no hearing improvement. Patients in Group A (hearing improvement 1-2 month post stapedotomy)--12 cases (44.4%) with hearing improvement confirmed by pure-tone audiometry and Group B--5 cases (55.6%) in which no sign of hearing improvement in pure-tone audiometry was reported. In patients who intraopertively reported hearing improvement not supported by the pure-tone audiometry the following factors seem to play a vital role: a) strong suggestion and willingness of improvement after surgical treatment, b) specific condition of the whisper hearing test at the operating room environment, c) patient's stress during the surgery and strong fear of possible revision surgery.

Wpływ rodzaju protezki strzemiączka na stopień poprawy słuchu w chirurgii strzemiączka – analiza retrospektywna 350 przypadków

Retrospective analysis of the post-op hearing results in stapes surgery using different types of materials for stapes prosthesis after 12 months follow up. The total number of 350 otosclerosis patients who underwent surgical treatment at the Otosurgery Department, Medical University of Lodz from 1980-2002. All patients included in the study were divided into 4 groups: group 1 (N=54)--Portmann's method interposition, group 2 (N=160)--stapes replaced with the Shea-type prosthesis, group 3 (N=60)--platinum wire prosthesis (Zini-type), group 4 (N=76)--teflon-piston operation (Fisch-type). The 12 months post-op mean value for air-bone gap (500, 1000, 2000 Hz) presented the following values: group 1-19 dB, group 2-15.9 dB, group 3-18.4 dB, group 4-13.5 dB. The percentage of patients with the mean air-bone gap value of 15 dB or less (500, 1000, 2000 Hz) has the following values in each group: group 1-75%, group 2-81.3%, group 3-83%, group 4-85%. 12 months post-op hearing results compared between the 4 studied groups showed statistically not significant differences. Our experience with teflon-piston prosthesis shows the lowest post-op mean value of the air-bone gap.

Long-term hearing results after stapes surgery: a 20-year follow-up.

The aim of this study was to evaluate the results of stapes surgery after 20 years of follow-up and to compare the results between large fenestra versus small fenestra stapedotomy. Retrospective clinical study. Tertiary referral center (university hospital). One hundred forty-two patients with otosclerosis treated by surgery. Eighty patients had a total stapedectomy with House-wire prosthesis and 62 patients a stapedotomy with Teflon-piston prosthesis. Preoperative, postoperative, and long-term hearing thresholds were compared. Patients filled in a questionnaire about the impact of surgery on the quality of life and postoperative symptoms. The long-term pure tone average improvement did not differ significantly between the techniques compared with the preoperative values. The air-bone gap tended to enlarge as a function of time. The change in the pure tone average was 0.9 dB per year for both techniques. In the questionnaire, some patients reported vertigo, tinnitus, loud noise intolerance, and taste disturbances. Loud noise intolerance seemed to persist in the long term. Surgery had no effect on preoperative tinnitus. There were no statistically significant differences between the techniques regarding hearing results. Over the long term, both techniques are safe and effective in restoring hearing and improving quality of life.

Effect of teflon piston diameter on hearing result after stapedotomy

This study compares hearing results after stapedotomy by 0.6 mm and 0.8 mm teflon pistons. Retrospective analysis studied 100 patients randomly selected who underwent stapedotomy for otosclerosis with insertion of 0.8 mm teflon piston prosthesis and 100 patients with 0.6 mm teflon piston prosthesis. Air-conduction hearing level in both groups were measured before and after the procedure and the gain of the air conduction between the 2 groups at different frequencies were compared statistically. The group with the 0.8 mm prosthesis had better results that were statistically significant and more pronounced at lower frequencies. (Otolaryngol Head Neck Surg 2001;124:279-81.)

Correction of incus necrosis during revision stapes surgery using the causse malleus prosthesis

Revision stapes surgery has historically yielded poor results when compared with primary stapes surgery. Although revision of the oval window is the most dangerous part of revision stapedectomy, the most common difficulty with reconstruction of the ossicular chain is correction of incus necrosis. This article reports on the use of a malleus to oval window Teflon piston prosthesis (Causse malleus prosthesis) for correction of incus necrosis encountered during revision stapes surgery. The criteria for patient selection, surgical procedure, and discussion of the advantages and disadvantages of this surgical technique are presented. Revision stapes surgery has historically yielded poor results when compared with primary stapes surgery. Although revision of the oval window is the most dangerous part of revision stapedectomy, the most common difficulty with reconstruction of the ossicular chain is correction of incus necrosis. This article reports on the use of a malleus to oval window Teflon piston prosthesis (Causse malleus prosthesis) for correction of incus necrosis encountered during revision stapes surgery. The criteria for patient selection, surgical procedure, and discussion of the advantages and disadvantages of this surgical technique are presented.

Malleus Teflon piston prosthesis.

The malleus Teflon piston prosthesis is very useful to reconstruct the sound conducting mechanism of the middle ear in absent or inadequate incus, congenital malformation of the middle ear, and epitympanic fixation of the incus and/or malleus. It has a thin-walled loop at its upper end to lessen the tendency for ulceration of the overlying drum with an inside diameter of 1 mm to fit around the mid portion of the handle of the malleus at an angle of 30 degrees to the shaft of the prosthesis. There is a cut in the distal part of the loop through which it is snapped onto the handle of the malleus after it is separated from the drum. Examples of the various situations in which this prosthesis has been used will be shown together with the results regarding hearing gain, complications, and other problems. Those situations in which the prosthesis was used in 1972 will be reviewed to give a 10-year follow-up, plus some notable examples of other uses of the prosthesis from other times.

Histopathologic Findings following Surgical Procedures for Stapedial Ankylosis

The histopathologic findings in the temporal bones of four patients with otosclerosis who had stapes operations, each according to a different surgical technique, are discussed. The four surgical methods employed included: 1) stapes interposition with a vein graft; 2) polyethylene strut over a vein graft; 3) fenestration of an obliterated oval window with a teflon piston; and 4) wire prosthesis over a remaining, shattered footplate. The first, third and fourth method provided a very satisfactory seal for the oval window. The polyethylene strut, on the other hand, protruded deeply into the vestibule and was about to perforate through the thinned vein graft. In the three remaining patients, the vestibular end of the prostheses was in fairly good alignment with the level of the oval window. Within the middle ear cavity all prostheses were invested in a thin coat of endothelial cells and connective tissue. Whereas the ring of the teflon piston prosthesis caused no bony atrophy, the stainless steel wire had induced a localized deossification at its site of attachment on the incus. The third and fourth cases disclosed some adhesions in the perilymphatic space around the oval window. All temporal bones revealed no injury to, or rupture of the utricle or saccule.

Histopathologic Findings following Surgical Procedures for Stapedial Ankylosis

The histopathologic findings in the temporal bones of four patients with otosclerosis who had stapes operations, each according to a different surgical technique, are discussed. The four surgical methods employed included: 1) stapes interposition with a vein graft; 2) polyethylene strut over a vein graft; 3) fenestration of an obliterated oval window with a teflon piston; and 4) wire prosthesis over a remaining, shattered footplate. The first, third and fourth method provided a very satisfactory seal for the oval window. The polyethylene strut, on the other hand, protruded deeply into the vestibule and was about to perforate through the thinned vein graft. In the three remaining patients, the vestibular end of the prostheses was in fairly good alignment with the level or the oval window. Within the middle ear cavity all prostheses were invested in a thin coat of endothelial cells and connective tissue. Whereas the ring of the teflon piston prosthesis caused no bony atrophy, the stainless steel wire had induced a localized deossification at its site of attachment on the incus. The third and fourth cases disclosed some adhesions in the perilymphatic space around the oval window. All temporal bones revealed no injury to, or rupture of the utricle or saccule.