Pediatric cerebral cysts: comparison of early complications following fenestration versus shunting procedures.

Objective: Characterize practice patterns and acute (30-day) surgical complications following fenestration and shunt procedures for the treatment of cerebral cysts in pediatric patients.Methods: This study utilized the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) Pediatric database. Patients were identified by International Classification of Disease codes for cerebral cysts and Current Procedural Terminology codes for shunting or fenestration. Demographic data, preoperative comorbidities, and postoperative complications were compared between the two procedures.Results: 741 patients were included in the data analysis, with a majority aged 4 years or younger (55.9%) and a male predominance (62.6%). Fenestration was performed in 590 (79.6%) patients. Primary shunting was performed in 151 (20.4%) patients. Patients who received shunts were more commonly aged 0-4 years and had proportionately worse preoperative health status. No statistically significant differences in postoperative complications were detected. Reoperation rate was 7.9% and 8.6% in the shunt and fenestration groups, respectively. Common reasons for reoperation were shunt revision or replacement and shunt placement after fenestration. Patients requiring shunting after a failed fenestration tended to be younger with higher American Society of Anesthesiologists (ASA) classification.Discussion: Fenestrations are performed more often than shunting. Generally, children who receive shunts are younger than those who undergo fenestration. Acute surgical risk appears to be similar for both operations.

Laser vs drill for footplate fenestration during stapedotomy: a systematic review and meta-analysis of hearing results.

OBJECTIVE: Stapes surgery is the gold standard surgical treatment nowadays for otosclerosis. Several controversies on the procedure have been reported; surgical techniques for most favorable outcomes are still on discussion. The objective of this study is to present an update of evidence-based medicine concerning the utilization of lasers and drilling for footplate fenestration during stapedotomy surgery. A systematic review and meta-analysis were conducted. MATERIALS AND METHODS: Publications in English in the last 5 years were searched in the PubMed/MEDLINE database and were systematically reviewed. A total of three articles were included according to the inclusion criteria, obtaining a total of 1531 patients managed surgically for otosclerosis, using laser or drill for footplate fenestration. Data were systematically extracted and hearing results were compared in a meta-analysis. RESULTS: For the drill group, a total of 978 patients were retrieved and data were obtained as follows: mean age was 50 years old; the female proportion was 62%; mean preoperative air-bone gap (ABG) of 28 dB; mean postoperative ABG of 8 dB; mean ABG improvement of 20 dB; an ABG closure rate to < 10 dB of 74%. For the laser group, a total of 553 patients were retrieved, data were obtained as follows: mean age was 47 years old; the female proportion was 63%; preoperative ABG of 26 dB; postoperative ABG of 8 dB; mean ABG improvement of 18 dB; an ABG closure rate to < 10 dB of 72%. CONCLUSION: The results from this study reveal that in regard to postoperative hearing results, surgical outcomes are comparable, and there is no statistically significant difference between the utilization of drills and lasers as a surgical instrument for the fenestration of the stapes footplate during stapedotomy surgery.

Short-term audiological outcomes of stapedotomy: microdrill at low revolutions versus manual perforator to perform a small footplate fenestra. A prospective observational study.

<b>Introduction:</b> Stapedotomy is currently the surgical technique of choice for treating otosclerosis. Despite this, there is no agreement about the best technique to perform a small fenestra footplate, therefore multiple procedures have been proposed. The aim of this study was to investigate the hearing outcomes of microdrill and manual perforator. <br><b>Material and Methods:</b> An observational prospective study was carried out on patients who underwent stapedotomy. We analyzed the hearing threshold in two groups of patients according to the way the fenestra footplate was realized by microdrill or manual perforator. <br><b>Results:</b> A total of 113 patients were evaluated. Postoperative hearing gain of the microdrill group was 23.29 (18.58) dB HL 95% CI (18.40-28.18), while in the manual perforator group, it was 22.67 (12.91) dB HL 95% CI (19.07-26.26). Both groups were statistically significant. Postoperative bone conductive hearing threshold at the frequencies of 0.5, 1 and 2 KHz and postoperative air conductive hearing threshold at the frequencies of 2 and 4 KHz showed statistically significant differences in the manual perforator group. The closure of air-bone gap was higher in the microdrill group with statistically significant differences. <br><b>Conclusion:</b> Both manual perforator and microdrill have good hearing outcomes at six months after surgery. The manual perforator has better audiological outcomes than microdrill. Hence, the manual perforator is a safe technique and can be used in centers that do not have other methods to make the small fenestra.

History of Otosclerosis and Stapes Surgery.

The current advancements in otosclerosis therapy cannot be fully appreciated without studying the history, rediscovery, and modification of a once-forgotten procedure. The evolution of stapes surgery can be best summarized into 4 noteworthy eras: the preantibiotic era (which was forgotten and then rediscovered), the fenestration era (mainstreamed by Julius Lempert), the mobilization era (led by Samuel Rosen), and the modern stapedectomy era (revived and revolutionized by John Shea). Each era is unique with its own challenges and ingenious techniques to overcome what used to be among the leading causes of deafness.

Enhanced viral-mediated cochlear gene delivery in adult mice by combining canal fenestration with round window membrane inoculation.

Cochlear gene therapy holds promise for the treatment of genetic deafness. Assessing its impact in adult murine models of hearing loss, however, has been hampered by technical challenges that have made it difficult to establish a robust method to deliver transgenes to the mature murine inner ear. Here in we demonstrate the feasibility of a combined round window membrane injection and semi-circular canal fenestration technique in the adult cochlea. Injection of both AAV2/9 and AAV2/Anc80L65 via this approach in P15-16 and P56-60 mice permits robust eGFP transduction of virtually all inner hair cells throughout the cochlea with variable transduction of vestibular hair cells. Auditory thresholds are not compromised. Transduction rate and cell tropism is primarily influenced by viral titer and AAV serotype but not age at injection. This approach is safe, versatile and efficient. Its use will facilitate studies using cochlear gene therapy in murine models of hearing loss over a wide range of time points.

Stapedectomy Versus Stapedotomy.

Stapedectomy and stapedotomy represent the state-of-the-art surgical procedures in addressing the conductive hearing loss caused by otosclerosis. Their high rates of success and long-term stability have been demonstrated repeatedly in many studies. In comparing the short- and long-term results of the 2 procedures, it is evident that stapedotomy confers better hearing gain at high frequencies and lower complication rates. Modified stapes mobilization procedures may represent the next major development in stapes surgery in a selected patient population.

The Effect of Piston Diameter in Stapedotomy for Otosclerosis: A Temporal Bone Model.

HYPOTHESIS: The use of larger-diameter pistons in stapedotomy leads to better hearing outcomes compared with the use of smaller-diameter pistons. There is an interaction between stapes piston diameter and fenestration diameter. BACKGROUND: Otosclerosis can be treated surgically by removing part of the stapes and bypassing the stapes footplate with a prosthesis. Available piston shaft diameters range between 0.3 and 0.8 mm. There has been a tendency toward the use of smaller-diameter pistons, because of a suspected decreased risk of cochlear trauma and subsequent sensorineural hearing loss (SNHL) with smaller pistons. However, mathematical models, temporal bone studies, and clinical studies suggest that the use of larger-diameter pistons is associated with better hearing outcomes. METHODS: Three fresh-frozen, non-pathologic temporal bones were harvested from human cadaveric donors. Acoustic stimuli in the form of pure tones from 250 to 8000 Hz were generated at 110 dB sound pressure level. A total of 16 frequencies in a 1/3-octave series were used. Stapes and round window velocities in response to the acoustic stimuli were measured at multiple equally spaced points covering the stapes footplate and round window using a scanning laser Doppler interferometry system. Eight sets of measurements were performed in each temporal bone: 1) normal condition (mobile stapes), 2) stapes fixation and stapedotomy followed by insertion of 3) a 0.4-mm-diameter piston in a 0.5-mm-diameter fenestration, 4) a 0.4-mm-diameter piston in a 0.7-mm-diameter fenestration, 5) a 0.4-mm-diameter piston in a 0.9-mm-diameter fenestration, 6) a 0.6-mm-diameter piston in a 0.7-mm-diameter fenestration, 7) a 0.6-mm-diameter piston in a 0.9-mm-diameter fenestration, and 8) a 0.8-mm-diameter piston in a 0.9-mm-diameter fenestration. RESULTS: At midrange frequencies, between 500 and 4000 Hz, round window velocities increased by 2 to 3 dB when using a 0.6-mm-diameter piston compared with a 0.4-mm-diameter piston. Using a 0.8-mm-diameter piston led to a further increase in round window velocities by 2 to 4 dB. CONCLUSION: Our results suggest a modest effect of piston diameter on hearing results following stapedotomy.

Spinal Extradural Arachnoid Cyst / 대한신경손상학회지

A spinal extradural arachnoid cyst (SEAC) results from a rare small defect of the dura matter that leads to cerebrospinal fluid accumulation and communication defects between the cyst and the subarachnoid space. There is consensus for the treatment of the dural defect, but not for the treatment of the cyst. Some advocate a total resection of the cysts and repair of the communication site to prevent the recurrence of a SEAC, while others recommended more conservative therapy. Here we report the outcomes of selective laminectomy and closure of the dural defect for a 72-year-old and a 33-year-old woman. Magnetic resonance imaging of these patients showed an extradural cyst from T12 to L4 and an arachnoid cyst at the posterior epidural space of T12 to L2. For both patients, we surgically fenestrated the cyst and repaired the dural defect using a partial hemi-laminectomy. The patient’s symptoms dramatically subsided, and follow-up radiological images show a complete disappearance of the cyst in both patients. Our results suggest that fenestration of the cyst can be a safe and effective approach in treating SEACs compared to a classical complete resection of the cyst wall with multilevel laminectomy.

X-ray microtomography study of otic capsule deficiencies: three-dimensional modelling of the fissula ante fenestram.

BACKGROUND: The postulated sites of perilymph fistulae involve otic capsule deficiencies, in particular, at the fissula ante fenestram. Histological studies have revealed this to be a channel extending from the middle ear, and becoming continuous with the inner ear medial to the anterior limit of the oval window. The relationship between a patent fissula and symptoms of perilymph fistula is contentious. OBJECTIVE: The understanding of the anatomy of the fissula ante fenestram is incomplete. Histopathology is inherently destructive to the delicate ultrastructure of the middle and inner ear. Conversely, X-ray microtomography allows non-destructive examination of the otic capsule. In this study, we used X-ray microtomography to characterise the fissula ante fenestram. MATERIALS AND METHODS: We imaged cadaveric temporal bones with X-ray microtomography. We used the Avizo Fire (Visualization Science Group, Merignac Cedex, France) software to perform post-processing and image analysis. RESULTS: Three-dimensional modelling of the fissula ante fenestram allowed stratification into four forms: rudimentary pit; partial fissula; complete occluded fissula; and complete patent fissula. CONCLUSION: X-ray microtomography showed that the fissula ante fenestram is present in various forms from rudimentary pit to complete deficiency of the otic capsule. This understanding may have implications for otologic surgery and clinical diagnosis of perilymph fistula.

Labyrinthine fenestration for stapes fixation in chronic ear disease others than otosclerosis.

The objective of this study is to assess the results of labyrinthine fenestration for fixed stapes in chronic ear disease. Using a prospective database, pre- and postoperative audiometric data from patients undergoing labyrinthine fenestration for fixation of the stapes in chronic ear disease others than otosclerosis between 2002 and 2012 were evaluated. Twenty-three labyrinthine fenestrations in chronic ear disease were performed (17 malleo-stapedotomies, 4 incus-stapedotomies, 1 neo-malleus-stapedotomy, 1 TORP-stapedotomy). Overall, the mean short-term (2 months) and long-term (42 months) postoperative air-bone gap (0.5-3 kHz) were 17.5 and 16.5 dB, respectively; long-term air-bone gap of <20 dB was obtained in 73 % of patients. There was no significant difference in air-bone gap closure between tympanosclerotic and post inflammatory osteogenic fixation of the stapes (p = 0.267). Hearing benefit success using the 'Belfast rule of the thumb' was achieved in 48 %. Normal bilateral hearing was achieved in 17 % and bilateral symmetric hearing impairment in 26 %. Only in 4 %, bone conduction worsened by more than 5 dB. Labyrinthine fenestration is an option in selected cases of stapes fixation in chronic ear disease and provides hearing gain without significant risk for sensorineural hearing loss. In those already selected cases, hearing benefit success 'Belfast rule of the thumb' is achieved only in half of the cases. This and the possible alternatives, should therefore be discussed preoperatively.

Influence of laser-assisted cochleostomy on acoustically evoked compound action potentials in the guinea pig.

HYPOTHESIS: Making a cochleostomy with a laser can affect the inner ear function. BACKGROUND: Different types of lasers can be used to create a fenestration in the footplate of the stapes during stapedotomy. Because of variations in absorption spectra of the laser light in various tissues or fluids, each laser has its own characteristics and possible side effects. MATERIALS AND METHODS: The basal turns of the cochleae of 20 guinea pigs were fenestrated using 4 types of lasers (thulium, KTP, CO2, diode; all groups n = 4). A control group (n = 4) was included to correct for the effects of the surgery alone. At 3 different time points, acoustically evoked compound action potentials (CAPs) were recorded at 5 frequencies and at different sound pressure levels. N1-P2 amplitudes were measured, and subsequently, thresholds were calculated. A repeated measures analysis of variance was used to investigate differences between groups. RESULTS: There was a decrease in CAP amplitudes and an increase in CAP thresholds after cochleostomy with each laser. The increase in thresholds was significantly larger for higher frequencies. The thulium laser evoked the largest threshold shifts, the KTP laser the smallest with the CO2, and diode lasers in intermediate positions. Overall, there was an increase in latencies after treatment. CONCLUSION: Laser treatment on or near the cochlea can cause damage to the sensitivity of the cochlea for sound. The thulium laser seems to be the worst choice in this respect.

Comparing mechanical effects and sound production of KTP, thulium, and CO2 laser in stapedotomy.

HYPOTHESIS: The mechanical and acoustic effects that occur during laser-assisted stapedotomy differ among KTP, CO2, and thulium lasers. BACKGROUND: Making a fenestration in stapedotomy with a laser minimizes the risk of a floating footplate caused by mechanical forces. Theoretically, the lasers used in stapedotomy could inflict mechanical trauma because of absorption in the perilymph, causing vaporization bubbles. These bubbles can generate a shock wave, when imploding. METHODS: In an inner ear model, we made a fenestration in a fresh human stapes with KTP, CO2, and thulium laser. During the fenestration, we performed high-speed imaging from different angles to capture mechanical effects. The sounds produced by the fenestration were recorded simultaneously with a hydrophone; these recordings were compared with acoustics produced by a conventional microburr fenestration. RESULTS: KTP laser fenestration showed little mechanical effects, with minimal sound production. With CO2 laser, miniscule bubbles arose in the vestibule; imploding of these bubbles corresponded to the acoustics. Thulium laser fenestration showed large bubbles in the vestibule, with a larger sound production than the other two lasers. Each type of laser generated significantly less noise than the microburr. The microburr maximally reached 95 ± 7 dB(A), compared with 49 ± 8 dB(A) for KTP, 68 ± 4 dB(A) for CO2, and 83 ± 6 dB(A) for thulium. CONCLUSION: Mechanical and acoustic effects differ among lasers used for stapedotomy. Based on their relatively small effects, KTP and CO2 lasers are preferable to thulium laser.

Capturing thermal, mechanical, and acoustic effects of the diode (980 nm) laser in stapedotomy.

INTRODUCTION: The diode laser, with a wavelength of 980 nm, has promising characteristics for being used for the fenestration during stapedotomy. It is known that at this wavelength absorption in pigmented tissues is high, and absorption in water is relatively low compared with medical lasers in the infrared, making it theoretically an applicable laser for stapes surgery in patients with otosclerosis. Another important advantage is that, with respect to other lasers, this device is relatively inexpensive. Despite the potential advantages, the available literature only shows limited reports of this laser being used in stapes surgery. The present article evaluates the thermal, mechanical, and acoustic properties of the diode laser during stapes surgery. METHODS: For the mechanical effects, high-speed imaging with a frame rate up to 4000 f/s (=250 µs resolution) was performed in an inner ear model. For thermal effects, the high-speed Schlieren technique was used. Acoustics were recorded by a hydrophone, incorporated in the model. Pulse settings were 100 ms, 3 W, which are the same settings used during stapes surgery. RESULTS: The application of the diode laser resulted in limited mechanical and thermal effects. Impulse noise was low with an average of 52 (SD, 7.8) dB (A). Before carbonization of the tip of the delivery laser, fiber enhances ablation of the footplate. CONCLUSION: The 980-nm diode laser is a useful tool for laser-assisted stapedotomy in patients with otosclerosis. Mechanical, thermal, and acoustic effects are limited and well within the safety limits.

Effect of KTP laser cochleostomy on morphology in the guinea pig inner ear.

BACKGROUND: The main advantage of using the KTP (potassium-titanyl-phosphate) laser for stapedotomy instead of the conventional micropick instrument is the smaller risk for mechanical damage. However, the KTP laser could theoretically inflict damage to inner ear structures. We hypothesize that KTP laser light [wavelength (λ) = 532 nm] is hardly absorbed in perilymph but well absorbed in solid structures. The aim of this pilot study was to assess if damage occurred after KTP laser cochleostomy in an animal model and, if so, to what extent and at which settings. MATERIALS AND METHODS: In six guinea pigs, a KTP laser cochleostomy at the basal turn was created. Laser settings of 1, 3 and 5 W and 100 ms pulse time (n = 2 each) were used. Histological preparations were studied for damage to neuroendothelial cells and intrascalar blood. RESULTS: No damage to inner ear neuroendothelial cells was observed, even at the highest power. Blood clots in the scala tympani from vessels in the cochlear wall were seen. The effects were minimal in the lowest, currently clinically used settings. CONCLUSION: KTP laser cochleostomy gives no damage to inner ear neuroendothelial cells but may cause intrascalar hemorrhages.

Laser versus conventional fenestration in stapedotomy for otosclerosis: a systematic review.

OBJECTIVES/HYPOTHESIS: To assess hearing results and complications following primary stapedotomy in otosclerosis patients comparing the use of laser and conventional techniques for fenestration. STUDY DESIGN: Systematic literature review. METHODS: A systematic bibliographic search was conducted in PubMed, Embase, the Cochrane Library, Cumulative Index to Nursing and Allied Health Literature, and Scopus. Studies reporting original data on the effect of laser fenestration, compared to conventional techniques, on closure of air-bone gap in patients undergoing primary stapedotomy were included. Directness of evidence and risk of bias of the selected articles were assessed. Studies with low directness of evidence, high risk of bias, or both were not further analyzed. The absolute risks, risk differences, and 95% confidence intervals were extracted only for studies with moderate to high directness of evidence and moderate to low risk of bias. RESULTS: In total, 383 unique studies were retrieved. Eight of these (including 999 procedures) provided high or moderate directness of evidence and carried a moderate risk of bias, and were considered eligible for data extraction. The included studies show no consistent difference in postoperative air-bone gap closure or immediate postoperative vertigo. CONCLUSIONS: Both footplate fractures and sensorineural hearing loss appear to occur more frequently in the conventional group than in the laser group. Therefore, we prefer laser above conventional methods for footplate fenestration in primary stapedotomy. LEVEL OF EVIDENCE: NA.

Factors affecting fenestration of the footplate in stapes surgery: effectiveness of Fisch's reversal steps stapedotomy.

OBJECTIVE: To analyze the factors affecting the fenestration of the footplate in stapes surgery and to evaluate the effectiveness of Fisch's reversal steps stapedotomy. STUDY DESIGN: Retrospective study. PATIENTS: A total of 191 patients with otosclerosis in whom 230 primary stapes surgeries were performed by 1 surgeon in 3 tertiary hospitals. MAIN OUTCOME MEASURE: Evaluation of factors affecting the fenestration of the footplate in stapes surgery by logistic regression analysis. RESULTS: Stapedotomy (small hole in stapes footplate) was performed in 148 ears (64.3%). Partial stapedectomy (half removal of stapes footplate) was performed in 65 ears (28.3%). Total stapedectomy (total removal of stapes footplate) was performed in 17 ears (7.4%). Stapedotomy could be performed in 72.1% of cases (75/104) in which the stapes suprastructure was removed after insertion of the prosthesis and in 57.9% of cases (73/126) in which the stapes suprastructure was removed before the insertion. Stapedotomy could be performed in 65.4% of cases (117/179) in which a 0.6-mm-thick Schuknecht-type Teflon wire piston was used and in 60.8% (31/51) in which a whole Teflon piston was used. Multivariate analysis of factors affect stapedotomy using logistic regression analysis showed that the surgical order of the removal of the stapes suprastructure and insertion of the prosthesis were the most important 2 factors. CONCLUSION: Fisch's reversal steps technique was useful in performing stapedotomy in all otosclerosis patients. Manipulation of the prosthesis when crimping it to the incus is also important. The prosthesis should be crimped onto the incus and inserted in the footplate opening gently and atraumatically.