Achieving Cochlear Therapeutic Hypothermia through Irrigation of the Mastoid and Tympanic Cavities.

INTRODUCTION: Mild therapeutic hypothermia (MTH) is an exciting nonpharmaceutical otoprotection strategy. In this study, we applied simple irrigation of the tympanic and mastoid cavities to understand the timing of both achieving MTH and recovery back to euthermic temperatures for application in the clinical setting. METHODS: Three human temporal bones were used in this study in the temporal bone laboratory. A standard mastoidectomy was performed on each followed by the insertion of temperature probes into the basal turn of the cochlea via a middle cranial fossa approach. The temporal bones were warmed in heated bead baths to 37°C. The tympanic and mastoid cavities were then irrigated with room temperature water, and intracochlear temperature readings were recorded every minute. After 15 min, irrigation was stopped, and temperature readings were collected until temporal bones returned to euthermic levels. RESULTS: Intracochlear MTH was achieved within the first minute of irrigating the tympanic and mastoid cavities. Intracochlear temperatures plateaued after 5 min around 30°C. Discontinuation of irrigation resulted in the temperature rising logarithmically above the MTH levels after 9-10 min. CONCLUSION: Intracochlear MTH can be achieved via irrigation of the tympanic and mastoid cavities with room temperature irrigation within 60 s. After irrigation for 5 min, hypothermic temperatures will remain therapeutic for 10 min following cessation of irrigation.

Comparison between classic 'Fisch' and 'corner-tag' meatoplasty techniques after canal wall down tympanomastoidectomy.

PURPOSE: To compare outcomes of two different methods of meatoplasty following Canal Wall-Down tympanomastoidectomy. METHODS: A retrospective case review study of 48 patients with non-complicated unsafe chronic suppurative otitis media candidate for post-auricular canal wall-down tympanomastoidectomy via a post-auricular approach at Otolaryngology department, Benha university hospitals from January 2021 to January 2023, all were operated for the first time, and divided into 2 groups each of 24 patients. Group A submitted for classic 'Fisch', and group B 'Corner-Tag' meatoplasty. RESULTS: The mean age was 28.88 ± 13.26 years in group A and 33.33 ± 16.04 years in group B. Only one patient (4.2 %) in each group developed wound infection and none in both groups developed perichondritis. Two patients (8.3 %) in group B compared to only one patient (4.2 %) in group A had granulations on the meatal incision. One patient (4.2 % of group A) needed revision meatoplasty. Group B needed more time for epithelization (mean 7.33 ± 0.96 weeks) than group A (mean 6.5 ± 0.88 weeks; P = 0.003*) also resulted in wider mean new meatus in group B (mean 10.50 ± 1.02 mm) than in group A (mean 9.63 ± 1.41 mm; P = 0.02*). CONCLUSION: Both techniques had comparable post-operative complications. 'Corner-Tag' technique needed more time for healing and epithelization but gave a wider new meatal diameter than 'Fisch' meatoplasty after one year of follow-up.

Audiometric outcomes following surgery for spontaneous temporal bone cerebrospinal fluid leaks - A single institution study.

PURPOSE: To assess the audiometric outcomes following surgical repair of spontaneous temporal bone cerebrospinal fluid otorrhea and compare different surgical approaches. MATERIALS AND METHODS: Retrospective review of adults (≥18 years old) who underwent repair of spontaneous CSF leak between 2011 and 2022. Audiometric outcomes were compared across the three surgical groups: transmastoid, middle cranial fossa and combined. RESULTS: Thirty-nine patients (40 ears) met the inclusion criteria (71.8 % females; mean age 59.77 +/- 12.4). Forty-two percent underwent transmastoid, 12.5 % middle cranial fossa and 45 % transmastoid-middle cranial fossa. Four patients (10 %) had recurrence, 3 in the transmastoid group and 1 in the combined approach. The mean change in air-bone gap (ABG) for all patients (postoperative-preoperative) was -7.4 (paired t-test, p-value = 0.0003). The postoperative ABG was closed in 28 (70 %) ears (postoperative ABG ≤ 15). The mean change in pure tone average (PTA) for all patients (postoperative-preoperative) was -4.1 (paired t-test, p-value = 0.13). The mean change in word recognition scores (WRS) for all patients (postoperative-preoperative) was -3 (paired t-test, p-value = 0.35). On multivariable analysis (controlling for site and reconstruction material), there was no significant difference in ABG, PTA and WRS change between surgical groups. CONCLUSIONS: Transmastoid, middle cranial fossa and combined approaches are all effective in treatment of spontaneous CSF leaks and all showed mean decrease in post-operative ABG. Transmastoid approach showed the greatest decrease in ABG and PTA (although middle cranial fossa approach shows the greatest decrease, when excluding profound hearing loss in a patient with superior canal dehiscence). Further studies comparing audiometric outcomes are needed.

Intratemporal facial nerve neurofibroma causing facial paralysis in an infant: Case report and review of the literature.

This article describes the first recorded case of intratemporal neurofibroma in an infant. A literature review of all other existing cases of intratemporal neurofibroma is performed, finding that the majority of cases involve multiple segments and can be found in the mastoid segment most often. Most common symptoms described included facial paralysis, otalgia, and conductive hearing loss, respectively.

Trans-mastoid plugging of superior semicircular canal dehiscence: long-term follow-up.

OBJECTIVE: To evaluate the long-term outcomes of trans-mastoid plugging of superior semicircular canal dehiscence (SSCD), focusing on complicated cases. METHODS: In this cohort study, we included all patients who underwent trans-mastoid plugging of SSCD between 2009 and 2019. We evaluated the symptoms (autophony, sound-/pressure-induced vertigo, disequilibrium, aural fullness and pulsatile tinnitus) before and 1 year after surgery in the medical records. We systematically assessed the current symptoms 6.2 ± 3 years postoperative (range 2.2-12.3 years) using questionnaires sent by post and validated by telephone interviews. We also documented any complications and the need for further procedures. We compared pure tone and speech audiometry before and 1 year after surgery. Finally, the degree of mastoid pneumatisation and mastoid tegmen anatomy were reviewed on preoperative CT scans. RESULTS: We included 24 ears in 23 patients. No complications were recorded, and none required a second procedure for SSCD. Following surgery, oscillopsia and Tullio phenomena resolved in all patients. Hyperacusis, autophony, and aural fullness were also settled in all patients except one. Balance impairment persisted to some degree in 35% of patients. No deterioration over the years was reported regarding the above symptoms. On average, bone conduction pure tone average pre- and 1 year postoperative were 13.7 ± 17 and 20.5 ± 18 dB, respectively (P = 0.002). Air bone gaps were reduced from 12.7 ± 8 to 5.9 ± 6 (P = 0.001). Two patients had a significant sclerotic mastoid, three had a prominent low-lying mastoid tegmen, and two had both. Anatomy had no effect on outcome. CONCLUSION: Trans-mastoid plugging of SSCD is a reliable and effective technique which achieves long-lasting symptom control, even in cases with sclerotic mastoid or low-lying mastoid tegmen.

External auditory canal reconstruction using a novel mastoidoplasty technique during canal wall down mastoidectomy: how I do it.

BACKGROUND: While mastoid obliteration techniques have received much attention in decreasing the disadvantages associated with the resultant mastoid cavity from canal wall down procedures, techniques for an anatomically normal looking ear canal reconstruction to increase the feasibility of hearing aid fitting are less commonly discussed as an alternative. METHODS: Our mastoidoplasty technique basically utilises an inferiorly based periosteal flap with or without temporalis muscles and fascia to obliterate the epitympanum and reconstruct the external auditory canal (EAC). Stay sutures are used to keep them in place. For larger cavities, demineralized bone matrix (DBM) is used to obliterate the mastoid cavity and support the neo-EAC. CONCLUSIONS: The concept of our mastoidoplasty potentially provides a very useful alternative in recreating a near normal ear canal anatomy avoiding cavity problems as well as facilitating hearing aid fitting with canal type hearing aids after canal wall down mastoidectomy.

Association of the superior semicircular canal and tegmen tympani dehiscences and its relationship with the pneumatisation of the temporal bone.

PURPOSE: To analyse the degree of pneumatisation of the temporal bone when there is an association between dehiscence of the superior semicircular canal and dehiscence of the tegmen tympani. MATERIALS AND METHODS: We analysed a retrospective CT study of 124 selected cases. A single inclusion criterion was applied: the presence of a dehiscence of the tegmen tympani. On the other hand, the degree of temporal pneumatisation was assessed by axial and coronal planes, and has been divided into the following grades O, I, II and III, according to the status and relationship of the mastoid, the bony labyrinth, the petrous segment of the carotid canal and sigmoid sinus. RESULTS: Of the 124 cases studied, 35 (28.2%) presented both dehiscences. In 26 of the 35 (47.3%), grade II pneumatisation, 4 (14,8%), grade I, and 5 (11,9%) grade III was observed, with a statistically significant relationship (p < 0.001). On the other hand, we did not find a significant relationship when relating both dehiscences in any age or sex group. However, when relating the degree of pneumatisation to sex, among those with grade III pneumatisation, the proportion of men (52.4%) was significantly higher than that of women (47.6%) (p = 0.017). CONCLUSION: We have detected a statistically significant relationship between the coexistence of grade II pneumatisation and the presence of both dehiscences in the temporal bone.

Long-term clinical and radiological results for fat graft obliteration in subtotal petrosectomy and cochlear implant surgery: a retrospective clinical study.

PURPOSE: The study aimed to evaluate the long-term clinical, radiological, and functional results for subtotal petrosectomy and cochlear implant surgery with closure of the external auditory canal and fat obliteration. METHODS: We retrospectively included all consecutive cases of simultaneous subtotal petrosectomy and cochlear implant surgery performed at a tertiary referral center between 2009 and 2016 using the same surgical technique. All patients underwent postoperative high-resolution computed tomography (HRCT) and annual audiological assessments. A 5-year minimum clinical, radiological, and audiological follow-up was performed. The early and late postoperative results were compared. The main outcome measures were complications, postauricular retraction, fat graft reabsorption, and audiological outcomes. RESULTS: Twenty-nine procedures performed in 23 patients (six bilateral) met the inclusion criteria. The mean age of the patients was 67 ± 13.4 years and mean follow-up duration was 7.5 ± 2 years. At follow-up, postauricular retraction was detected in 24 cases (82.8%), including five cases (17.1%) with subcutaneous protrusion of implant and array. Fat graft volume was significantly reduced at late-HRCT in terms of maximum diameter (2.24 ± 1.0 cm vs 3.69 ± 0.7 cm; p < 0.0005) and surface area (1.88 ± 1.2 vs 4.24 ± 1.6 cm2, p < 0.0005). Six patients had extracochlear electrodes at late-HRCT (3/6 had an increased number of extracochlear electrodes), with a lowering of this group's performance of - 15% (p < 0.005) in the follow-up speech comprehension test. CONCLUSIONS: Subtotal petrosectomy with cochlear implantation is an effective long-term technique in selected cases. Fat grafts showed significant reabsorption at long-term follow-up with reaeration of the middle ear spaces. Prolonged clinical and radiological follow-up is recommended for monitoring implant performances and late complications.

Risk factors for recurrent acute mastoiditis in pediatric patients: a registry-based cohort study.

OBJECTIVE: To describe characteristics of pediatric patients with recurrent acute mastoiditis, and to identify risk factors for this condition. STUDY DESIGN: A retrospective cohort study. SETTING: Data based on electronic medical records of the largest Health Maintenance Organization in Israel. METHODS: Children hospitalized due to acute mastoiditis during the years 2008-2018 were identified, and their diagnosis was verified. Patients with recurrent acute mastoiditis were identified and grouped, and their characteristics were outlined and compared to those of the original group to identify risk factors for recurrence. RESULTS: During the 11-year period, a total of 1115 cases of children hospitalized due to acute mastoiditis were identified with a weighted incidence rate of 7.8/100,000. Of this group, 57 patients were diagnosed with recurrence following a full clinical recovery. The incidence proportion of recurrent acute mastoiditis was 5.1% (57/1115), male-to-female ratio was 27:30, 73.4% were younger than 24 months, the median period from the first episode was 3.4 months (IQR 2.0;10.0), and 82.5% of the patients (n = 47) had a single recurrence, whereas 18.5% (n = 10) had two recurrences or more. Mastoidectomy and swelling over the mastoid area during the first episode were identified as the main risk factors for recurrent mastoiditis HR = 4.7 [(2.7-8.2), p < 0.001] and HR = 2.55 [(1.4-4.8), p = 0.003], respectively. Mastoidectomy was the only independent significant risk factor for recurrence in a multivariate analysis. CONCLUSIONS: Mastoidectomy and swelling over the mastoid area during the first episode of acute mastoiditis were found strongly related independent risk factor for future recurrent episodes of acute mastoiditis.

Sex Estimation From Measurements of the Mastoid Triangle and Volume of the Mastoid Air Cell System Using Classical and Machine Learning Methods: A Comparative Analysis.

ABSTRACT: Previous studies on the sexual dimorphism of the mastoid triangle have typically focused on linear and area measurements. No studies in the literature have used mastoid air cell system volume measurements for direct anthropological or forensic sex determination. The aims of this study were to investigate the applicability of mastoid air cell system volume measurements and mastoid triangle measurements separately and combined for sex estimation, and to determine the accuracy of sex estimation rates using machine learning algorithms and discriminant function analysis of these data. On 200 computed tomography images, the distances constituting the edges of the mastoid triangle were measured, and the area was calculated using these measurements. A region-growing algorithm was used to determine the volume of the mastoid air cell system. The univariate sex determination accuracy was calculated for all parameters. Stepwise discriminant function analysis was performed for sex estimation. Multiple machine learning methods have also been used. All measurements of the mastoid triangle and volumes of the mastoid air cell system were higher in males than in females. The accurate sex estimation rate was determined to be 79.5% using stepwise discriminant function analysis and 88.5% using machine learning methods.

Mastoid Emissary Foramina in Dry Skulls: Its Morphometry, Topography, and Associated Clinical Implications.

Mastoid emissary foramen transmitting mastoid emissary vein connects the posterior auricular vein with the sigmoid sinus. This foramen and so the mastoid emissary vein varies in prevalence, number, size and location, knowledge of which is essential for carrying out uneventful surgeries, especially retrosigmoid, mastoidectomy, and skull base surgeries. There is a paucity of literature on this foramen in the Indian context, so the study was done. The purpose of the study is to elaborate on the prevalence, number, size, and location of mastoid foramen in dry adult skulls. The study was conducted in the Department of Anatomy using 90 dry skulls of unknown age and sex, and prevalence, number, size, and location in these skulls were noted. The mastoid foramen was detected in 27.8% of skulls, with an incidence of 31.1% and 12.2% on right and left sides of skulls, respectively. The number of foramina ranged between 1 and 4. The mean diameter of this foramen was 0.9 mm, and the most frequent location was mastoid process. The detailed morphology and morphometry of mastoid foramen are of utmost use to neurosurgeons, ENT surgeons, radiologists, and vascular surgeons as it transmits mastoid emissary vein and meningeal branch of the occipital artery, which may be injured during various surgical procedures involving mastoid region and skull base causing catastrophic hemorrhage. In addition to this, mastoid emissary vein may be the source of thrombus, causing thrombus of sigmoid sinus creating helm of neurological complications.

Study of Topography of Stylomastoid Foramen With Respect to Nearby Landmarks to Carry Out Facial Nerve Block With Minimum Complications.

Nadbath facial nerve block is the most common procedure to anesthetize the facial nerve at stylomastoid foramen in intraocular surgeries, but it is associated with complications. Also, this foramen exhibits ethnic and racial variations with regard to its location. There is scanty literature describing the topographical location of this foramen. So, the study is carried out. The purpose of the study is to describe the topography of stylomastoid foramen from the surrounding landmarks so that Nadbath facial nerve block can be performed with minimum complications. The study was conducted using 80 adult dry skulls of unknown age and sex, and the distance of this foramen was measured from the tip, upper end, and lower end of the anterior border of the mastoid process and jugular foramen. The statistical analysis consisting of mean, SD, median, range mode, and t test was calculated. Mean distances of stylomastoid foramen from the upper end, the lower end of anterior border and tip of mastoid process and jugular foramen on right side were 1.5±0.16, 1.02±0.09, 0.84±0.09, and 0.49±0.06 cm and those on left side were 1.5±0.16, 1.02±0.09, 0.84±0.09, and 0.5±0.06 cm, respectively. The mode of these distances was 1.5, 1, 0.8, and 0.5, both on the right and left sides. The topographic information about stylomastoid foramen given in this study is useful to anesthetists to carry out Nadbath facial nerve block successfully with minimum complications.

Interpretation of the nine-step test for Eustachian tube function should consider mastoid cavity volume.

INTRODUCTION: The modified nine-step test is a classical method for evaluating Eustachian tube function. However, clinical interpretation of the increased maximal difference in middle ear pressure (mdMEP) in the modified nine-step test is unknown. We hypothesised that the different reservoir effects of the mastoid cavity can bias the results of the modified nine-step test. METHODS: A total of 108 consecutive participants (216 ears) were retrospectively screened. Of these, 55 participants (82 ears) who met the inclusion/exclusion criteria were enrolled. The volumetric results of the mastoid cavity, parameters of the modified nine-step test (mdMEP, middle ear pressure, tympanic membrane compliance), and demographic data were analysed. RESULTS: A significant negative correlation was found between mdMEP and mastoid cavity volume (R = .467, p < .001). Ears with mdMEP >70 daPa showed poor pneumatization in the mastoid cavity, with volumes less than 3000 mm3 (10th percentile of all ears analysed). Ears with mastoid cavity volumes lower than the 25th percentile showed a significantly higher mdMEP (p < .001). Patients with mastoid cavity volumes higher than the 75th percentile were significantly younger (p < .001). Multivariate regression analysis for mdMEP showed a good fit (R = .854) using factors including middle ear pressure, admittance and, most importantly, the reciprocal of mastoid volume (Beta = 0.752, p < .001). CONCLUSIONS: The mdMEP, the main parameter of the modified nine-step test, was negatively correlated with the mastoid cavity volume. Therefore, the results of the modified nine-step test should be interpreted with consideration of mastoid cavity volume.

The Mastoid Crevasse and 3-Dimensional Considerations in Deep Plane Neck Lifting.

BACKGROUND: Advances in face and neck lifting involve release of tethering points along the superficial musculoaponeurotic system-platysma complex to freely manipulate the deep natural glide plane in the face and neck. OBJECTIVES: The aim of this article was to determine a combination of deep plane techniques for addressing the face and neck and to elucidate, for the first time, a measurable endpoint for the gonial angle. Analysis of deep plane tethering and decussation zones was also undertaken. METHODS: Extended deep plane surgery performed in 79 patients (158 hemifaces; age, 30-75 years; 95% female), over a 3-month period, was reviewed. Patients were followed for 1 year. Measurements were performed systematically during deep plane face and neck lifting. RESULTS: Before intervention, the mean [standard deviation] gonial depth was 9.4 [3.6] mm on the left and 8.3 [2.7] mm on the right. The mean depth created below the gonial angle when measuring the traditional suspension to the anterior mastoid was 15.8 [3.3] mm on the left and 13.7 [2.5] mm on the right. The distance postoperatively when measuring the gonial depth after performing the crevasse technique was 23.2 [2.2] mm on the left and 22.5 [2.5] mm on the right. This represents a mean increase in the advancement of 7.4 mm on the left and 8.8 mm on the right (average, 8.1 mm) which was demonstrated to be statistically significant bilaterally (P < .0001). CONCLUSIONS: The deep plane techniques described here aid manipulation of the deep plane and deep neck space, while also providing measurable endpoints and more effective modes of fixation by utilizing the mastoid crevasse. The use of techniques that release tension and allow redrape produce the most natural and well-balanced results.

150 years ago: Schwartze's 1873 mastoidectomy and its implementation over the following 2 years.

BACKGROUND: In 1873, Hermann Schwartze and Adolf Eysell described a new surgical technique for treating mastoid disease using a mallet, chisels, and gouges of various sizes instead of trephines or drill instruments also called "modern mastoidectomy." On the 150th jubilee of this landmark article, we pay tribute by studying the reception and implementation of mastoidectomy in the 2 years following its publication. METHODS: The commentaries published in the otological and medical literature between the second part of 1873 to the end of 1875 were studied with an emphasis on the three specialized otological journals and the otological textbooks that existed during this period. RESULTS AND CONCLUSION: The princeps paper Ueber die künstliche Eröffnung des Warzenfortsatzes ("On the artificial opening of the mastoid process") by Hermann Schwartze and Adolf Eysell published in 1873 was rapidly disseminated in the medical literature for nearly 1 year, and then entered a phase of evaluation followed by a phase of extension and implementation, before finding its definitive place in the history of mastoid process surgery.

Diagnostic and Imaging Findings in Inflammatory Opacifications of the Middle Ear: A Review of the Literature.

Opacification in the middle ear and mastoid region can stem from a wide range of factors. In terms of diagnostic imaging, CT is the primary tool due to its exceptional spatial resolution, particularly for examining the temporal bone and ossicles. MRI complements this by offering detailed soft tissue lesion characterization and assessing involvement in the inner ear and cranial nerves. This study focuses on inflammatory causes of opacification in the middle ear and mastoid, with an emphasis on the utility of CT and MRI. This comprehensive review aimed to provide a practical framework for considering potential differential diagnoses.

[The population morbidity with diseases of ear and mastoid and accessibility of otorhinolaryngological care].

The article analyses level and dynamics of morbidity of diseases of ear and mastoid in the Sakha Republic (Yakutia) in 2020-2021 and availability of otorhinolaryngological care. The methods of comparative statistics and mathematical analysis were applied to analyze official data provided by the Yakut Republic Medical Information and Analytical Center, the specialized Department of Otorhinolaryngology, the Republic Hospital № 2 - Center for Emergency Medical Care and the Federal State Statistics Service of Russia. The study established increasing trend of increasing morbidity of these diseases in both the adult and child population. In 2021, the growth rate of overall morbidity of adult population reached 17.7% and 8.8% in children, as compared to 2020. The primary morbidity of adults made up to 22.3%, in children - 15.7%. The comparative analysis demonstrated higher rates of general morbidity in the Republic: by 0.5% as compared with the Russian Federation and by 14.1% as compared with the Far Eastern Federal Okrug. The level of primary morbidity was lower than similar indicators of the compared territories by 17.1% and 3.0%, respectively. It is worth noting that analyzed morbidity of diseases of ear and mastoid reflects prevalence of ENT diseases in the region only indirectly, as the statistical data do not allow to estimate separately rate of upper respiratory tract lesions. Meanwhile, respiratory diseases rank first in the structure of population diseases in Yakutia. The growth of disability in children due to diseases of ear and mastoid requires attention. Among children of 0-17 years old, the indicator of primary disability increased from 0.38 to 0.8 per 10,000 of children population (increase of 110.5%); in children 0-3 years old - from 0.9 to 2.3 per 10,000 of the child population (an increase of 155.6%). The analysis of the number of beds in otorhinolaryngology wards established that that the bed capacity per 10,000 population was 0.6 that is significantly lower than the established standards. The article emphasizes need to adjust the Federal standards for hospital bed capacity, taking into account climatic and geographical conditions of the region, which contribute to spread and chronization of ENT diseases.

An anatomical study of the sigmoid sinus artery: Application to the transmastoid approach.

INTRODUCTION: We aimed to investigate the morphological features of the artery that traverse the sigmoid sinus's lateral surface and to discuss this structure's clinical relevance. METHODS: Ten sides from five cadaveric Caucasian heads were used for gross anatomical dissection to investigate the morphological features of the sigmoid sinus artery (SSA), and additional five sides were used for histological observation. RESULTS: The SSA was found on eight out of ten sides (80%). The mean diameter of the SSA was 0.3 mm. The mean distance from the tip of the mastoid process to the artery was 20.3 mm. Histological observation identified extradural and intradural courses of SSA. The intradural course was further categorized into protruding and non-protruding types. In the protruding type, the SSA traveled within the dura but indented into the bone, making it more or less an intraosseous artery. In the non-protruding type, the SSA traveled within the dura but did not protrude into the bone but rather indented into the lumen of the SS. In all sections, both intradural and extradural courses were identified simultaneously. CONCLUSIONS: When the mastoid foramen is observed, it does not always only carry an emissary vein but also an artery. The SSA could be considered a "warning landmark" during bone drilling for the transmastoid approach.

Anatomical study of the mastoid foramina and mastoid emissary veins: classification and application to localizing the sigmoid sinus.

The mastoid foramen (MF) is located on the mastoid process of the temporal bone, adjacent to the occipitomastoid suture or the parietomastoid suture, and contains the mastoid emissary vein (MEV). In retrosigmoid craniotomy, the MEV has been used to localize the position of the sigmoid sinus and, thus, the placement of the initial burr hole. Therefore, this study aimed to examine the exact location and variants of the MF and MEV to determine if their use in localizing the sigmoid sinus is reasonable. The sample in this study comprised 22 adult dried skulls (44 sides). MF were identified and classified into five types based on location, prevalence, whether they communicated with the sigmoid sinus and exact entrance into the groove of the sigmoid sinus. The diameters and relative locations of the MF in the skull were measured and recorded. Finally, the skulls were drilled to investigate the course of the MEV. Additionally, ten latex-injected sides from human cadavers were also dissected to follow the MEV, especially in cases with more than one vein. We found that type I MFs (single foramen) were the most prevalent (50%). These MFs were mainly located on the occipitomastoid suture; only one case on the right side was adjacent to the parietomastoid suture. Type II (paired foramina) was the second most prevalent (22.73%), followed by type III (13.64%), type 0 (9.09%), and type IV (4.55%). The diameter of the external opening in a connecting MF (2.43 ± 0.79) was twice that of a non-connecting MF (1.14 ± 0.56). Interestingly, on one side, two MFs on the external surface shared a single internal opening; the MEV bifurcated. MFs followed three different courses: ascending, almost horizontal, and descending. Regardless of how many external openings there were for the MF, these all ended at a single opening in the groove for the sigmoid sinus. For cadaveric specimens with multiple MEVs, all terminated in the sigmoid sinus as a single vein, with the more medial veins terminating more medially into the sinus. Based on our study, the MF/MEV can guide the surgeon and help localize the deeper-lying sigmoid sinus. Knowledge of this anatomical relationship could be an adjunct to neuronavigational technologies.

The Mastoid Skin Graft: A Fast, Efficient Donor Site for Auricle Reconstruction After Mohs Surgery.

BACKGROUND: Mohs micrographic surgery has been considered the gold standard for treating nonmelanoma skin cancers. Approximately 8% to 10% of skin cancers requiring Mohs surgery occur on the auricle. Skin grafts can be used to achieve optimal functional and cosmetic results. OBJECTIVES: To describe a skin graft technique using the mastoid area as a donor site for auricular reconstruction following Mohs micrographic surgery, to achieve optimal esthetic results in functionally important areas. METHODS: This retrospective study assessed the outcomes of patients who underwent MMS in an out-patient Mohs surgery clinic from 2010 to 2021. All patients had MMS of the auricle with reconstruction using a split thickness skin graft harvested from the mastoid area. RESULTS: A total of 154 patients were included. The average lesion diameter was 13.7 mm (range 5-30 mm), excised in an average of 1.9 rounds of MMS. Skin graft success rate was 96%. Complications included one patient with a hypertrophic scar. The cosmetic appearance of the recipient site was rated as excellent by 87.5% of patients. All patients rated the cosmetic appearance of the donor area as excellent and well-concealed. CONCLUSIONS: Split thickness skin grafts harvested from the mastoid area are a quick and efficient reconstruction method for post-Mohs auricular defects.