Mastoid Surgery Research Articles

Landmarks for the preservation of the middle temporal artery during mastoid surgery: Cadaveric dissection study

ImportanceThe middle temporal artery flap is a vascularized periosteal flap that is highly useful for otologic reconstruction including the middle cranial fossa, mastoidectomy defect, and external auditory canal. The course of the artery is close to the external auditory canal and is easily injured during preliminary exposure and elevation of flaps. ObjectivesTo describe the course of the middle temporal artery in relation to the external auditory canal and the superficial temporal artery in order to enhance preservation and use in otologic reconstruction. DesignDissection of preserved, injected cadaveric temporal bones. SettingAnatomical laboratory. ParticipantsSeven cadaveric temporal bones. InterventionTemporal bones were dissected in a planar manner to identify the middle temporal artery along the squamous temporal bone to its origin. The superior border of the external auditory canal was divided, horizontally, into thirds to create three measurement points. Distances between the middle temporal artery and the bony portion of the external auditory canal were then determined. Main outcomes and measuresHorizontal diameter of the external auditory canal, distance from the superior-most border of the external auditory canal to the middle temporal artery, various patterns of the middle temporal artery. ResultsThe middle temporal artery branched from the superficial temporal artery in all specimens. Mean horizontal diameter of the external auditory canal was 9.97mm. Mean distances between the bony portion of the external auditory canal and middle temporal artery for the first, second, and third points along the horizontal diameter of the external auditory canal were 1.57, 2.96, and 4.02mm, respectively. In at least one specimen, the artery dipped into the external auditory canal. Conclusions and relevanceThe middle temporal artery runs closest to the external auditory canal at the anterosuperior border. To preserve the middle temporal artery for use in reconstruction after otologic surgery, the surgeon should avoid dissection superior to the external auditory canal until the artery is positively identified.

Anatomical Relationship of the Middle Cranial Fossa Dura to Surface Landmarks of the Temporal Bone.

The suprameatal crest and temporal line provides a reliable landmark to the middle fossa dura. Surface anatomy of the temporal bone is used to guide mastoid surgery, but studies investigating these landmarks are limited. The aim of this study was to examine the anatomical relationship of the middle fossa dura to the temporal line. Thirty-two fresh hemicephalic temporal bones were prepared by drawing four lines along the mastoid including the suprameatal crest and temporal line (line 2), one line 5 mm superior to line 2 (line 1), and one 5 mm inferior to line 2 (line 3), and at Reid's base line (line 4). Four points were marked along these lines anterior to posterior 3 mm apart. A 1 mm bur was used to drill perpendicular to these points to examine the relationship to the middle fossa dura. The dura was found inferior to line 2 in 6.3% at point 1, 6.3% at point 2, 9.4% at point 3, and 18.8% at point 4. The dura in line 1 was found inferior to point 1 in 52.1%, point 2 in 46.9%, point 3 in 56.3%, and point 4 in 62.5%. Only one specimen (3.1%) had dura lying inferior to line 3. No specimens were inferior line 4 at any point. The dura of the middle fossa lies superior the temporal line in >80% of specimens and at least 5 mm superior in nearly half. This indicates the temporal line or a line slightly inferior to this is reliably inferior the middle fossa dura.

Bioactive glass obliteration of the mastoid significantly improves surgical outcome in non-cholesteatomatous chronic otitis media patients.

This retrospective follow-up study evaluates the efficacy and safety of bioactive glass (BAG) S53P4 when applied as filler material in mastoid obliteration surgery performed on non-cholesteatomatous chronic otitis media (NC-COM) patients with chronically discharging ears despite conservative therapy. 94 Patients (96 ears) were included. Patients underwent either intact canal wall (ICW) or canal wall down (CWD) mastoid surgery between 2005 and 2015. The intervention group comprised 23 patients (23 ears) who were treated with additional mastoid obliteration using BAG S53P4; the remaining 71 patients (73 ears) were considered controls. All patients underwent preoperative CT scanning of the mastoid. Primary functional outcome, as defined by control of suppuration, was assessed using Merchant's scale. Hearing results as measured by air-bone gap and the incidence of adverse events were assessed as secondary outcomes. Thirty-two ears (44%) in the control group (n=73) achieved complete control of infection at the most recent postoperative clinic visit vs 17 (74%) in the S53P4 obliteration group (n=23). Comparing these outcomes yielded an odds ratio (OR) of 3.6 (p=0.012, 95% CI 1.3-10.3). Complete failure to manage infection significantly differed (p=0.048) between the control group (11 ears; 15%) and the S53P4 obliteration group (0 ears). No adverse events were observed in either group. Pre- and postoperative ABG results did not differ significantly between groups. Obliteration of the mastoid cavity using BAG S53P4 along with mastoidectomy in patients with chronically discharging NC-COM significantly improves the achievement of a dry and safe ear as compared to mastoidectomy alone. Importantly, no adverse events were observed with S53P4 BAG obliteration.

DISCHARGING OPEN MASTOID CAVITY CONTRIBUTING FACTORS & APPROACH TO MANAGEMNT

Chronic ear discharge is one of the indications of mastoid surgery, however; this persistent discharge may be the outstanding feature of complicated surgery ““Discharging open mastoid cavity”. Discharging open mastoid cavity is defined as persistently discharging cavity following canal-wall down mastoidectomy for a period more than 3-6 months.The etiology of this discharging cavity is mutifactorial. This study focuses the light on the contributing factors of the persistence of ear discharge after canal-wall down mastoid surgery: surgical , bacteriological & structural ( Eustachian tube function).Fifty patients with discharging cavity & 40 patients with dry cavity were gathered from the outpatient department of Al-Najaf teaching hospital during the period between " October 2002- November 200 . They were evaluated for discharging open mastoid cavity after canal-wall down mastoidectomy & was found that this problem is mutifactorial in etiology both surgical & non-surgical. We concluded that meticulous surgical technique is essential to prevent such a complication, beside prompt follow up to ensure dry cavity postoperatively

The incidence of hyperthermia during cochlear implant surgery in children.

Inadvertent hyperthermia during anaesthesia is a rare but life-threatening complication. We have encountered several cases of severe hyperthermia in paediatric patients undergoing anaesthesia for cochlear implantation. This study aimed to describe the clinical characteristics of children who developed hyperthermia while undergoing cochlear implantation, and to explore possible mechanisms and predisposing factors. The anaesthetic charts of all patients aged under 18 years who underwent cochlear implantation, or mastoid or ophthalmic surgery, between 1 January 2006 and 31 December 2009, at Soroka Medical Center in Beer Sheva, Israel, were reviewed. Patients undergoing mastoid and ophthalmic surgical procedures were used as controls. A larger percentage of patients who underwent cochlear implant surgery (10 per cent) developed hyperthermia compared to controls (0.7 per cent, p < 0.05). In five of the seven cases, hyperthermia appeared in combination with tachycardia and hypercapnia, adhering to the clinical triad of malignant hyperthermia. Patients undergoing cochlear implantation are susceptible to developing intra-operative hyperthermia. This article describes the hyperthermic events that occur during paediatric cochlear implantation, and attempts to identify potential triggers of hyperthermia.

Drill-induced Cochlear Injury During Otologic Surgery: Intracochlear Pressure Evidence of Acoustic Trauma.

Drilling on the incus produces intracochlear pressure changes comparable to pressures created by high-intensity acoustic stimuli. New-onset sensorineural hearing loss (SNHL) following mastoid surgery can occur secondary to inadvertent drilling on the ossicular chain. To investigate this, we test the hypothesis that high sound pressure levels are generated when a high-speed drill contacts the incus. Human cadaveric heads underwent mastoidectomy, and fiber-optic sensors were placed in scala tympani and vestibuli to measure intracochlear pressures (PIC). Stapes velocities (Vstap) were measured using single-axis laser Doppler vibrometry. PIC and Vstap were measured while drilling on the incus. Four-millimeter diamond and cutting burrs were used at drill speeds of 20k, 50k, and 80k Hz. No differences in peak equivalent ear canal noise exposures (134-165 dB SPL) were seen between drill speeds or burr types. Root-mean-square PIC amplitude calculated in third-octave bandwidths around 0.5, 1, 2, 4, and 8 kHz revealed equivalent ear canal (EAC) pressures up to 110 to 112 dB SPL. A statistically significant trend toward increasing noise exposure with decreasing drill speed was seen. No significant differences were noted between burr types. Calculations of equivalent EAC pressure from Vstap were significantly higher at 101 to 116 dB SPL. Our results suggest that incidental drilling on the ossicular chain can generate PIC comparable to high-intensity acoustic stimulation. Drill speed, but not burr type, significantly affected the magnitude of PIC. Inadvertent drilling on the ossicular chain produces intense cochlear stimulation that could cause SNHL.

Cerebrospinal Fluid Leakage During Temporal Bone Surgery: Selecting Intra-operative Dural Closure with a Dumbbell-Shaped Muscle Graft as a Surgical Approach.

Cerebrospinal fluid (CSF) leakages of the temporal bone may arise during mastoid surgery. The leakages can have multiple potential etiologies, for instance, using a cutting burr near the bony tegmen or monopolar electrocautery on the surface of the dura mater. In this paper, we introduced an effective and simple technique for the management of CSF leakages of the temporal bone. In a prospective case series, 36 patients (16 males and 20 females) who have had an experience of incidental or inevitable CSF otorrhea or otorhinorrhea during temporal bone surgery were selected. All patients were treated using a muscle graft in a dumbbell-shaped design through the dura defect at the Amir-Alam University Hospital between April 2005 and November 2008. The mean size of the defects was 5mm (a range of 2-10mm). A dumbbell-shaped autologous muscle graft was immediately successful in sealing the leakage in all patients. Only five patients (13.8%) had some evidence of leakage remaining on the day after the operation, which was subsequently resolved by conservative management in four of them (11.1%). Only one patient (2.7%) was subjected to a second operation for a new defect. Recurrence of CSF leakage or other related complications were not observed during about 7years of follow up. A free autologous muscle graft, using the dumbbell technique through a small to moderate dura defect is an effective, easily performed, and safe method to seal iatrogenic leakages of the temporal bone.

MASTOID SURGERY: Clinical Findings, Radiological findings&amp; Technique of Mastoid Surgery in Khartoum ENT Hospital and Omdurman military hospital

MASTOID SURGERY: Clinical Findings, Radiological findings&amp; Technique of Mastoid Surgery in Khartoum ENT Hospital and Omdurman military hospital

Comparative study between selective nerve blocks and the intravenous opioids in mastoid surgery

ObjectiveThis double-blind randomized trial was conducted to compare the efficacy of selective nerve blocks over intravenous use of morphine during mastoid surgery. Materials and methodsA total of 50 patients between the ages 25 to 45years were divided into two groups as per the anaesthetic techniques used; nerve block group (N) and intravenous morphine group (M). After induction of general anaesthesia and before surgical incision: Group N patients (nerve block group) were given Great Auricular Nerve (GAN) and Auriculo-Temporal Nerve (ATN) block with 0.25% bupivacaine. Group M patients (morphine group) received 0.1mg/kg morphine. In the post anaesthesia care unit (PACU), Visual Analogue Scale (VAS) was used to assess post operative pain, Ramsay Sedation Scale (RSS) for sedation and post operative nausea and vomiting (PONV) impact scale score. ResultsVAS scores and requirement of rescue analgesics in the PACU was significantly less in the N Group for first 3h. The group N patients had a less frequent incidence of vomiting requiring intervention and were ready to be discharged from hospital after 3h of surgery. ConclusionCombination of GAN and ATN block with general anaesthesia is an uncomplicated, effective and well tolerated method for the safe conduct of mastoid surgery.

Systematic radiographic evaluation of three potential implantation sites for a semi-implantable bone conduction device in 52 patients after previous mastoid surgery

4 (case series).

Platelet-Rich Plasma in Reconstruction of Posterior Meatal Wall after Canal Wall Down Mastoidectomy.

Introduction Canal wall down (CWD) mastoidectomy has many drawbacks, including chronic otorrhea not responding to medications, granulations, dizziness on exposure to cold or hot water, and tendency of debris accumulation in the mastoid cavity, demanding periodic cleaning. Many of these problems can be solved by reconstruction of the posterior meatal wall (PMW). Objectives To assess the results of PMW reconstruction after CWD mastoidectomy for cholesteatoma using titanium mesh and platelet-rich plasma (PRP) mixed with bone pate. Methods This study was conducted with 20 patients that have atticoantral chronic suppurative otitis media. All cases were subjected to CWD mastoid surgery with complete elimination of the disease and reconstruction of the PMW by titanium mesh and the mixture of PRP with bone pate. All patients were exposed to a full preoperative evaluation and full postoperative assessment of the complications, the appearance of the external auditory canal contour, and the hearing gain expressed by the change of the air bone gap postoperatively. Results The PMW reconstructed by titanium mesh and the mixture of PRP with bone pate showed a smooth contour. During the follow-up of 12 to 36 months, the postoperative appearance of the external auditory canal contour was found to be smooth without hidden pouches, irregularities or stenosis in all cases. No granulation, foreign body reaction, or extrusion and/or displacement of the titanium mesh were registered. No facial palsy or recurrent cholesteatoma was reported. Conclusion The surgical reconstruction of the PMW using PRP, bone pate and titanium mesh after CWD mastoidectomy appears to be reliable without considerable complications, giving a smooth appearance to the PMW.

The facial nerve study of multi-slice spiral computed tomography in congenital abnormality of external and middle ear

Objective:Images of temporal bone are obtained on Siemens 64 slices spiral CT scanner with high resolution scanning to describe the course of facial nerve for better preoperative evaluation of CAEMA.Method:To describe the course of facial nerve on rectangular coordinate system from three silce on HRCT, 29 patients(35 ears) are enrolled in our study in ENT department from November 2005 to March 2007 in the second affiliated hospital of sun yan sen university, who are all diagnosed not acquired deformity but CAEME, associated with no congenital deformity syndromes and no middle ear or mastoid operations before. Patients with bilateral ears deformity are 6, and unilateral ears deformity are 23 (13 right and 10 left) in the study group. The control group is the normal ears of unilateral ear deformity.Result:In the study group, the shortest distance from FN tympanic segment to oval window is shorter than that of the normal group (P< 0.05). In CAEME of unilateral ears the FN mastoid segment displaces anteriorly about 2.7 mm, and in CAEME of bilateral ears displaces 3.0mm, compared with the normal ears (P< 0.05). The deformity degree of auricle has correlations with anteriorly displacement of facial nerve mastoid segment (P< 0.05).Conclusion:The FN mastoid segment is anteriorly displacement in both bilateral and unilateral ear deformity. The deformity degree of auricle has correlations with anteriorly displacement of facial nerve mastoid segment. The lateral displacement of facial nerve doesn't occur usually in CAEME. The shortest distance between oval window and tympanic segment of FN become shorter than normal ears.

Evaluation of diffusion weighted MRI sequence as a predictor of middle ear cleft cholesteatoma: Imaging, operative and histopathological study

ObjectivesNon-echoplanar imaging (Non-EPI) MRI has been recently introduced to improve the detection of small sized cholesteatoma and decrease different artifacts occurring in the echo-planar diffusion weighted image (EPI DWI) technique. It is a time saving procedure in comparison to the delayed post-contrast imaging. We prospectively assessed the diagnostic accuracy of Non-EPI-DW sequences in the detection of middle ear cleft cholesteatoma. Material and methodsForty patients suspected to have cholesteatoma were collected from the ENT outpatient clinic of a tertiary referral center. Twenty patients underwent primary mastoid surgery, ten patients scheduled for revision mastoid surgery, while the remaining patients underwent second look operation after one year of their first surgery. All patients underwent Non-EPI-DW sequences prior to their planned surgery. Diagnosis of cholesteatoma was based on evidence of a hyperintense lesion on diffusion-weighted images that were correlated with the surgical findings and histopathological examination, which was used as the gold standard for diagnostic confirmation. Sensitivity, specificity and predictive values of MRI were estimated. ResultsDiffusion weighted imaging accurately predicted the presence of cholesteatoma in 88.2% of cases, and it correctly excluded it in 100% of cases. Sensitivity, specificity, positive and negative predictive values were 88.24%, 100%, 100% and 60%, respectively. Non-echo-planar DWI has been shown to have a high sensitivity and specificity for detecting recurrent cholesteatoma. ConclusionsNon-echoplanar DWI is an effective technique in cholesteatoma diagnosis. It is capable of detecting lesions larger than 2mm.

Point of Vulnerability of Facial Nerve during Mastoid Surgery in Indian Patients

Point of Vulnerability of Facial Nerve during Mastoid Surgery in Indian Patients

The effect of propofol infusion with topical epinephrine on cochlear blood flow and hearing: An experimental study

Background and objectivePropofol is the most commonly used intravenous (IV) anesthetic agent and is associated with hypotension upon induction of anesthesia. Intravenous propofol infusion has several properties that may be beneficial to patients undergoing middle ear surgery. Topical application of concentrated epinephrine is a valuable tool for achieving hemostasis in the middle ear and during mastoid surgery. The purpose of the present study was to determine the effects of propofol infusion with topical epinephrine on cochlear blood flow (CBF) and hearing in rats. Materials and methodsTwenty one male Sprague-Dawley rats were divided into three groups. The rate of intravenous infusion of propofol was 4–6 ml/kg/hour. The first group (control group, n = 7) was given IV infusion of phosphate buffered saline (PBS) with topical application of PBS in the round window. In study group A (n = 7), the effect of topical phosphate buffered saline with IV infusion of propofol on CBF and hearing was evaluated. In study group B (n = 7), additional effects of topical epinephrine with IV infusion of propofol on CBF and hearing were evaluated. The laser Doppler blood flowmeter, CBF, and the mean arterial blood pressure (MAP) were measured and analyzed. Additionally, hearing test using auditory brainstem response (ABR) was performed in both groups. ResultsIn both groups, infusion of propofol induced a time-dependent decrease in MAP. Approximately 30 min after the start of the propofol infusion, the CBF started to decrease slowly. The decrease in CBF was significantly greater in the study group compared to the control group. The threshold was elevated in the study group relative to the control group. ConclusionDuring middle ear surgery, use of IV infusion of propofol with topical epinephrine cotton ball or cottonoid application is not recommended.

Performance Assessment for Mastoidectomy.

Objective The aim of this report is to provide a review of the current literature for assessment of performance for mastoidectomy, to identify the current assessment tools available in the literature, and to summarize the evidence for their validity. Data Sources The MEDLINE database was accessed via PubMed. Review Methods Inclusion criteria consisted of English-language published articles that reported use of a mastoidectomy performance assessment tool. Studies ranged from 2007 to November 2015 and were divided into 2 groups: intraoperative assessments and those performed with simulation (cadaveric laboratory or virtual reality). Studies that contained specific reliability analyses were also highlighted. For each publication, validity evidence data were analyzed and interpreted according to conceptual definitions provided in a recent systematic review on the modern framework of validity evidence. Conclusions Twenty-three studies were identified that met our inclusion criteria for review, including 4 intraoperative objective assessment studies, 5 cadaveric studies, 10 virtual reality simulation studies, and 4 that used both cadaveric assessment and virtual reality. Implications for Practice A review of the literature revealed a wide variety of mastoidectomy assessment tools and varying levels of reliability and validity evidence. The assessment tool developed at Johns Hopkins possesses the most validity evidence of those reviewed. However, a number of agreed-on specific metrics could be integrated into a standardized assessment instrument to be used nationally. A universally agreed-on assessment tool will provide a means for developing standardized benchmarks for performing mastoid surgery.

Simulation for training in resource-restricted countries: using a scalable temporal bone surgical simulator.

Simulation for training in resource-restricted countries: using a scalable temporal bone surgical simulator.

Anatomic Variations in Temporal Bones Affect the Intensity of Nystagmus During Warm Caloric Irrigation.

Anatomic variables within the mastoid will correlate with intensity of caloric responses. During caloric irrigation, heat is transferred from the external auditory canal to the lateral semicircular canal (LSCC) through aerated mastoid bone. Temporal bone airspace volume and bone volume vary widely but the effect of this variation on caloric irrigation testing is not well characterized. Understanding this effect is necessary to understand how mastoid surgery may alter caloric irrigation results. Twenty-two mastoid airspace and bones, as well as LSCC, were reconstructed from computed tomography scans of 11 subjects with normal anatomy who underwent vestibular function evaluation. Respective surface area (SA) and volume (V) of the mastoid airspace, bones, LSCC, and distance from LSCC to tympanic membrane (LSCC-TM) were calculated. In addition, computed values from these anatomic structures were correlated with the maximum velocity of slow phase nystagmus during warm caloric irrigation (MVwarm). Our results showed that the combined effect of airspace SA:V, bone SA:V, LSCC SA:V, and LSCC-TM distance accounted for 69.5% of the variation in MVwarm. Airspace SA:V (R = 0.22) and LSCC SA:V (R2 = 0.02) positively correlated with MVwarm, while bone SA:V (R = 0.17) demonstrated an inverse correlation with MVwarm. Preliminary results from this pilot study suggest that a substantial amount of the variability in MVwarm can be explained by temporal bone anatomy. Results also indicate that the denser the bone, the more heat is transferred to the LSSC, whereas increased airspace serves as an insulator. A larger study is necessary to confirm our findings.

How to Avoid Facial Nerve Injury in Mastoidectomy?

Unexpected iatrogenic facial nerve paralysis not only affects facial disfiguration, but also imposes a devastating effect on the social, psychological, and economic aspects of an affected person's life at once. The aims of this study were to postulate where surgeons had mistakenly drilled or where obscured by granulations or by fibrous bands and to look for surgical approach with focused on the safety of facial nerve in mastoid surgery. We had found 14 cases of iatrogenic facial nerve injury (IFNI) during mastoid surgery for 5 years in Korea. The medical records of all the patients were obtained and analyzed injured site of facial nerve segment with surgical technique of mastoidectomy. Eleven patients underwent facial nerve exploration and three patients had conservative management. 43% (6 cases) of iatrogenic facial nerve injuries had occurred in tympanic segment, 28.5% (4 cases) of injuries in second genu combined with tympanic segment, and 28.5% (4 cases) of injuries in mastoid segment. Surgeons should try to identify the facial nerve using available landmarks and be kept in mind the anomalies of the facial nerve. With use of intraoperative facial nerve monitoring, the avoidance of in order to avoid IFNI would be possible in more cases. Many authors emphasized the importance of intraoperative facial nerve monitoring, even in primary otologic surgery. However, anatomical understanding of intratemporal landmarks with meticulous dissection could not be emphasized as possible to prevent IFNI.

The Role of Periosteum in Mastoid Surgery

The Role of Periosteum in Mastoid Surgery