Cadaveric Temporal Bone Dissection Research Articles

Evaluation of surgical skill among otology residents during cadaveric temporal bone dissection using an objective assessment tool

BackgroundThe acquisition and refinement of technical skills by the surgical residents are central to surgical teaching; hence, there is increasing interest in the objective assessment of surgical competence. In the field of otology, as of now, there are limited studies for the assessment of surgical competence, also, various subjective methods are being used to assess this vital aspect of training. This study aimed to validate and use an objective assessment tool for the valuation of surgical skills in a tertiary care teaching institute in the Indian subcontinent. MethodsSurgical competence of the residents in temporal bone dissection was assessed on a Likert scale by using a grading scale developed by Wan et al., after obtaining necessary permissions. ResultsJunior residents in ENT who had completed one year of residency in otolaryngology were asked to perform temporal bone surgery (cortical mastoidectomy) and were marked according to the proforma by two senior experienced otologists. The Cronbach's alpha value was .86 which is an indicator of good technical validity. ConclusionsIn our study, we have validated a grading scoring scale used by Wan et al. to objectively assess the ability of an otology resident to perform temporal bone surgery. It is recommended for use in Indian scenario due to its good technical validity. The use of a Likert scale to individually rate each competency makes the evaluation precise and simple.

Learning Curve of Two Handed Endoscopic Ear Surgery on Sheep Temporal Bone: A Fellow's Perspective.

The study puts forth the learning curve of two handed endoscopic middle ear dissection on a sheep temporal bone. It also highlights the usage of sheep temporal bone as an effective simulation technique for two-handed cadaveric temporal bone dissection. 6 sheep temporal bone models were dissected in a period of 15days. Harvesting of cartilage graft, endoscopic myringotomy and grommet insertion, cartilage butterfly tympanoplasty, ossiculoplasty, stapes surgery and facial nerve decompression, using the Endohold®, were conducted on each bone. There was a remarkable decrease in the time required for subsequent temporal bone dissections, with significant improvement in efficiency, accuracy and neatness of dissection. Practice and experience resulted in upliftment in the level of confidence of the fellow. Striking similarities were noticed between sheep and human temporal bones. Availability of both the hands with a clear endoscopic view made it easier and more convenient to perform various procedures. Two handed endoscopic technique provides an excellent approach for ear surgeries. Availability of both the hands for the delicate surgery along with the spectacular endoscopic view contributes to increase in efficiency and surgery outcome. Cadaveric dissection of sheep temporal bones provides a great learning experience for a trainee to practice these delicate and skilful two-handed endoscopic middle ear surgical exercises. Its easy availability and striking similarity of the anatomy makes it a boon for the beginners. It gives ample opportunity to the trainee to explore and learn the complex anatomy, try new skills and develop an expertise in this field. The efficiency and accuracy increases significantly with each dissection, smoothening out the steep learning curve, that is, for such fine and intricate surgical skills.

Our Experience of Anatomical Variations of Facial Nerve in Cadaveric Temporal Bone Dissection.

Cadaveric dissections helps aspiring ear surgeon to learn anatomy of temporal bone so as to avoid injury to the many vital structures. Objectives are to study the course of facial nerve and its variation in 50 cases of temporal bone dissection. To study the various parameter of the tympanomastoid segments of facial nerve, its relation with the important middle ear structures and their variations. To study the incidence of anatomical variations such as dehiscence of bony canal of facial nerve, bony overhang in the oval window region. The Current study was conducted at Dept. of ENT Temporal bone lab. 50 temporal bones were dissected to study the various parameters of the tympano-mastoid segments of the facial nerve, its relations with the important middle ear structures and their anomalies. The present study was carried out from Jan 2016 to Jan 2019. Out of 50 bones dissected, 44 (88%) bones were well pneumatised and 6(12%) bones were sclerotic. Length of the tympanic segment varied from 7.8 to 11.88mm with a mean of 9.47mm (± 1.06mm). In 17 bones (34%) length of the mastoid segment was 13.1-14mm, in 12 bones (24%) the length was 14.1-15mm, while in 10 bones (20%) it was 12-13mm. In 6 bones (12%) it was 15.1-16mm and < 12mm in 5 other bones (10%). The distance of second genu from outer cortex varied from 17.87-23.67mm with a mean of 19.64mm (± 1.42mm).Distance of chorda tympani from stylomastoid foramina varied from 3.4-7.8mm with a mean of 5.69mm (± 1.51mm). The study has provided knowledge of anatomy of temporal bone and its pneumatization pattern, the anatomy of the facial nerve, its variations and their incidence, relation of various middle ear landmarks with the facial nerve and proficiency in dissection.

Anatomy of the Round Window Region With Relation to Selection of Entry Site Into the Scala Tympani.

The aim of cochlear implantation is to safely insert an electrode array into the scala tympani (ST) while avoiding damage to surrounding structures. There is disagreement on the optimal way of entering the ST-the round window (RW) approach versus cochleostomy. Regardless of the chosen approach, it is vital to understand the regional anatomy, which is complex, difficult to conceptualize, and rarely dissected in temporal bone courses. The goal of this study was to examine the anatomy of the RW to gain more in-depth knowledge on the local relationships of the anatomical structures and propose an approach for entering the ST in cochlear implant surgery tailored to the encountered anatomy. Cadaveric prevalence study and expert opinion with literature review. Cadaveric temporal bone dissection (n = 13) by the first author assessing the RW anatomy. The round window membrane (RWM) and the osseous spiral lamina (OSL) are curved structures, each with a horizontal and a vertical part. The two horizontal portions are very closely apposed. The relationship between the OSL and the RWM determines the best site for a cochleostomy, which if required is best placed anteroinferiorly to the RWM. The distance between the oval window inferior margin and the RW membrane is less than 2 to 3 mm. The ST initially extends inferiorly and medially to the RW. The findings of our dissection have implications for cochlear implant surgery in aiming to avoid trauma to the OSL and basilar membrane and aid decision making in choosing the safest surgical approach. 5. Laryngoscope, 131:E598-E604, 2021.

A time-sensitive rubric for assessing mastoidectomy proficiency.

To develop a time-sensitive, standardized rubric for cadaveric temporal bone dissection for otolaryngology resident education. This is a five-year prospective cohort study that evaluated otolaryngology resident performance during sequential cadaveric temporal bone dissection courses at a single otolaryngology residency training program. A canal-wall-up mastoidectomy with a facial recess approach was performed adhering to a 30-minute time limit and graded according to a standardized rubric. Main outcome measures included: (1) correct structure identification and (2) injuries sustained to structures as compared by resident post-graduate year (PGY) level. Thirteen residents were evaluated from October 2012 to March 2017. This included 57 individual graded exercises performed over ten dissection courses. The average score for PGY-2 residents was lowest (68.9), and PGY-5 residents achieved the highest average score (87.7). Junior residents correctly identified fewer structures (77.5%) when compared to senior residents (91.3%), p<0.0001. Correct performance of a facial recess approach was achieved by 100% of senior residents, but only 59.3% of junior residents (p=0.0003). The percentage of major injuries, which included the facial nerve, tegmen, labyrinth, and ossicular chain, decreased each PGY-level from a maximum of 17% by PGY-2 residents to a minimum of 5% by PGY-5 residents. Senior residents correctly identify more structures and are able to complete a facial recess approach with higher fidelity when subjected to a time-sensitive graded mastoidectomy rubric.

Cadaveric Temporal Bone Dissection Workshop in a Tertiary ENT- HNS Centre: Is Our Teaching Satisfactory?

&#x0D; &#x0D; &#x0D; &#x0D; Introduction: Teaching learning skills are developed through various skill lab procedures. In the Department of ENT and HNS, Temporal Bone Dissection (TBD) is one of the methods of teaching. The TBD workshop conducted in the Department caters to most of the postgraduate students in the country. This study was conducted in the Department of ENT and HNS to evaluate the participants’ satisfaction on TBD course conducted in the Department.&#x0D; Methods: The TBD participants who had undergone TBD course in the Department of ENT and HNS were asked to fill up the questionnaire regarding the satisfaction of the TBD course and suggestions for the improvement of the course. The participants provided the response of the questionnaire in the email or in hand filling of the forms.&#x0D; Results: Total of 42 students responded to the questionnaire regarding the TBD course. 88% of the students graded it as good, 11% replied as satisfactory and 1% of them graded it as needs improvement. Maximum number of students commented on the inadequate time for dissection. Few participants replied the need of live demonstration in the course. 9.5% of the participants who had come for the course more than once commented on the great help done by the course in performing live otology surgery.&#x0D; Conclusions: Maximum participants were satisfied about the TBD workshop which helped them to know the intricate temporal bone anatomy.&#x0D; Key words: otology; questionnaire; Temporal Bone Dissection (TBD)&#x0D; &#x0D; &#x0D; &#x0D;

Herald Cell: The Gateway to Posterior Tympanotomy-A Cadaveric Study.

Posterior tympanotomy is the avenue to the facial recess of the middle ear from mastoid antrum. The entry into the facial recess in many cases is heralded by a distinct air cell before approaching the facial-chordal plane. The current study was undertaken to determine the prevalence of this 'Herald Cell' in an adult cadaveric population. It was a human cadaveric temporal bone dissection study. The bones were dissected to carry out cortical mastoidectomy and posterior tympanotomy using standard otologic drills under microscopic visualization (Leica M320 F12). Appropriate snapshots were taken to document the presence or absence of Herald cell. A total of 51 temporal bones were dissected (26 right, 25 left sided). The Herald cell was found to be present in 22 bones (43.1%). Herald cell, when present, is a convenient and reliable landmark to carry out a safe posterior tympanotomy.

A simple assessment tool for evaluation of cadaveric temporal bone dissection.

Objective metrics in skilled-based educational courses allow trainees and instructors to assess performance and monitor progress. The objective is to validate a concise, easy-to-use instrument for assessment of resident skill during a timed cadaveric temporal-bone (CTB) dissection. Retrospective analysis. An instrument was developed to assess resident performance on a yearly timed microdissection of CTB. Five neurotologists participated in the assessment. Each reviewer's score was compared to the score given by the senior neurotologist each year for every resident. Spearman's correlation analysis was then used to assess the reproducibility of the instrument in assessing resident performance. The ability of the instrument to distinguish among experienced and novice trainees and to demonstrate improvement with experience were also assessed. The instrument was created and used for 6 years. Thirty residents were assessed. Correlation of scores between the senior neurotologist and the other neurotologist together was very high (r = 0.883, P < 0.001). Three specific tasks distinguished novice from senior dissectors: posterior canal, opening the membranous labyrinth, and disruption of the ossicular chain. A new instrument for assessment of resident skill on CTB dissection is presented. The instrument is easy to use, and scores derived from it are consistent across reviewers. The new instrument distinguishes experienced trainees from novice trainees, is sensitive to individual experience, and has proved useful in providing trainees with objective performance measures. NA. Laryngoscope, 128:451-455, 2018.

Research awards 2015.

Dear Colleagues, The journal International Archives of Otorhinolaryngology has decided to award in 2015 the three best systematic review and/or literature review articles published in the journal in 2014, highlighting contributions that laid the foundations and concepts of universal knowledge. The purpose of the awards is to praise and acclaim distinguished authors, while also encouraging new talent in the field of international research in otorhinolaryngology. This complies with our objective to stimulate excellence in education and welcome technological developments through research and knowledge. The most outstanding articles were: Systematic Review 1°) Bittencourt, Aline Gomes; Burke, Patrick Rademaker; Jardim, Isabela de Souza; Brito, Rubens de; Tsuji, Robinson Koji; Fonseca, Anna Carolina de Oliveira; Bento, Ricardo Ferreira. Implantable and Semi-Implantable Hearing Aids: A Review of History, Indications, and Surgery. Int. Arch. Otorhinolaryngol. 2014;18(3):303–310. Review Article 2°) Naik, Sulabha M.; Naik, Mahendra S.; Bains, Nainjot Kaur. Cadaveric Temporal Bone Dissection: Is It Obsolete Today? Int. Arch. Otorhinolaryngol. 2014;18(1):63–67. 3°) Campagnolo, Andrea Maria; Priston, Jaqueline; Thoen, Rebecca Heidrich; Medeiros, Tatiana; Assuncao, Aida Regina. Laryngopharyngeal Reflux: Diagnosis, Treatment, and Latest Research. Int. Arch. Otorhinolaryngol. 2014;18(2):184–191. We hope to see you again in future publications. Best regards, Geraldo Pereira Jotz Editor-in-Chief International Archives of Otorhinolaryngology

Resident Participation in Cadaveric Temporal Bone Dissection Correlates With Improved Performance on a Standardized Skill Assessment Instrument

Increasing numbers of cadaveric temporal bone (CTB) dissection translates to improved scores on a timed microdissection of a CTB. Recent literature regarding resident education has focused on virtual learning. However, advocates for virtual temporal bone drilling admit that there is not yet a substitute for drilling a CTB. Retrospective review of resident performance on a standardized instrument during a timed microdissection of CTBs. Resident performance on the graded dissection was compared with the number of CTBs drilled during the year. Graded performance was also compared with the total number of CTBs dissected over 4 years of residency. Faculty assessed intraoperative skill of the senior residents. These rankings were compared with the number of CTBs drilled. Comparisons were made using Pearson's and Spearman's correlations. Comparison of test scores from the most recent resident year to the number of CTBs drilled during the corresponding year correlated well (r = 0.41, p = 0.002). The correlation between the score during the highest year of training and the cumulative number of CTB drilled during residency was even stronger (r = 0.604, p = 0.005). Faculty rankings correlated well comparing general surgical skills with TB surgical skills (r = 0.655, p = 0.008). Comparing faculty rankings of TB surgical skill with the number of CTB drilled during the final year of residency yielded a negative correlation (r = -0.8) but was not significant (p = 0.1). Greater exposure to CTB dissection correlates with improved scoring on a standardized instrument. Residents who struggle with temporal bone surgery tend to use CTB dissection more than those who are more facile.

Cadaveric temporal bone dissection: is it obsolete today?

Introduction Traditionally, surgical training in otology, is imparted by dissecting harvested human cadaveric temporal bones. However, maintenance of a cadaveric temporal bone laboratory is expensive and carries risk of exposure to infection. In recent times, other modalities of training are gaining ground and are likely to eventually replace cadaveric temporal bone dissection altogether. Objectives Other alternative methods of training are emerging. New technology like simulation and virtual reality as high-fidelity, safer alternatives, are making rapid strides as teaching tools. Other options are the use of animal temporal bones as teaching tools. The advantages of these are compared. Data Synthesis None of these modalities can replicate the innumerable anatomical variations which are a characteristic feature of the human temporal bone. A novice surgeon not only needs exposure to surgical anatomy and it's variations but also needs to develop hand-eye coordination skills to gain expertise. Conclusion Deliberate practice on human cadaveric temporal bones only, will confer both mastery in anatomy and surgical technique. The human cadaveric temporal bone is ideal simulator for training in otology.

Surgeon Behavior in a New Virtual Reality Temporal Bone Simulator Compared to Cadaveric Dissection

Objectives: The gold standard for teaching otologic surgery is cadaveric temporal bone (TB) dissection. However, learning may be enhanced by virtual reality (VR) simulation, which improves access and allows reproducibility. The main criticism of VR has been its lack of fidelity. The objectives of this study were to 1) assess the fidelity of a novel VR TB simulator, and 2) compare surgeon behavior to that in cadaveric TB dissection. Methods: A new 3D high-fidelity force-feedback VR simulator was developed for otologic procedures. Using prospective paired comparisons conducted in June 2012, 6 surgeons each performed a mastoidectomy, facial recess dissection, and a cochleostomy on a human cadaveric TB and in the VR simulator. Drill movements were then compared between cadaveric and VR trials. Results: Stroke number ( P = 0.69), speed ( P = 0.08), and rate ( P = 0.74) did not differ significantly between VR and cadaveric environments for all 3 stages. Compared to cadaveric dissection, subjects in the VR simulator spent less time completing each stage (236s vs. 698s; P = 0.01); spent a greater percentage of time drilling (69.5% vs. 30.4%; P = 0.002); and used a larger percentage of long strokes (39.8% vs. 6.9%; P &lt; 0.001). Conclusions: Drill stroke characteristics among surgeons in the VR simulator were similar to those in the cadaveric dissection. This suggests that real-life drilling behavior was replicated in VR and that it may be a useful adjunct to traditional TB dissection.

Face and Content Validation of a Virtual Reality Temporal Bone Simulator

To validate the VOXEL-MAN TempoSurg simulator for temporal bone dissection. Prospective international study. Otolaryngology departments of 2 academic health care institutions in the United Kingdom and United States. Eighty-five subjects were recruited consisting of an experienced and referent group. Participants performed a standardized familiarization session and temporal bone dissection task. Realism, training effectiveness, and global impressions were evaluated across 21 domains using a 5-point Likert-type scale. A score of 4 was the minimum threshold for acceptability. The experienced group comprised 25 otolaryngology trainers who had performed 150 mastoid operations. The referent group comprised 60 trainees (mean otolaryngology experience of 2.9 years). Familiarization took longer in the experienced group (P = .01). User-friendliness was positively rated (mean score 4.1). Seventy percent of participants rated anatomical appearance as acceptable. Trainers rated drill ergonomics worse than did trainees (P = .01). Simulation temporal bone training scored highly (mean score 4.3). Surgical anatomy, drill navigation, and hand-eye coordination accounted for this. Trainees were more likely to recommend temporal bone simulation to a colleague than were trainers (P = .01). Transferability of skills to the operating room was undecided (mean score 3.5). Realism of the VOXEL-MAN virtual reality temporal bone simulator is suboptimal in its current version. Nonetheless, it represents a useful adjunct to existing training methods and is particularly beneficial for novice surgeons before performing cadaveric temporal bone dissection. Improvements in realism, specifically drill ergonomics and visual-spatial perception during deeper temporal bone dissection, are warranted.

Can Virtual reality simulator be used as a training aid to improve cadaver temporal bone dissection? Results of a randomized blinded control trial

This study aims to determine whether there are improved performances in cadaver temporal bone dissection after training using a VR simulator as a teaching aid compared with traditional training methods Randomized control trial. Twenty participants with minimal temporal bone experience were recruited for this randomized control trial. After receiving the same didactic teaching they were randomized into two groups. The traditional group were to receive addition teaching via traditional teaching methods such as small group tutorials, videos, and models. The VR group received supervised teaching on the VR simulator. At the end of their teaching they were asked to perform a cadaveric temporal bone dissection and had their performance videoed and assessed by blinded assessors. The assessors judged the videos on four domains of assessments looking at the end product, injury size, overall performance, and technique. These assessments were based on the Welling's scale and OSATS. The VR group performed significantly better in the end product of the dissection (VR 80% vs. traditional 45%, P-value <.001) and caused smaller injuries to anatomic structures (VR 19% vs. traditional 36%, P-value = .01). They also did better in the overall performance score (VR 55% vs. traditional 35%, P-value = .04) There were no differences in the technique score. There was a fair to moderate degree of interrater reliability between the assessors (kappa = 0.33-0.47; Intraclass correlation coefficient = 0.34-0.76). Supervised teaching using a VR simulator seems to improve cadaveric temporal bone dissection performance compared with traditional teaching methods.

Cholesteatoma in three dimensions: a teaching tool and an aid to improved pre-operative consent

Otological surgeons face two recurring challenges. Firstly, we must foster an appreciation of the complex, three-dimensional anatomy of the temporal bone in order to enable our trainees to operate safely and independently. Secondly, we must explain to our patients the necessity for surgery which carries the potential for serious complication. Amira software was applied to pre-operative computed tomography images of temporal bones with cholesteatoma, to create three-dimensional computer images. Normal structures and cholesteatoma were displayed in a user-friendly, interactive format, allowing both trainee and patient to visualise disease and important structures within the temporal bone. Three cases, and their three-dimensional computer models are presented. Zoom, rotation and transparency functions complemented the three-dimensional effect. These three-dimensional models provided a useful adjunct to cadaveric temporal bone dissection and surgical experience for our residents' teaching programme. Also, patients with cholesteatoma reported a better understanding of their pre-operative condition when the models were used during the consenting process.

Establishing a temporal bone laboratory: considerations for ENT specialist training

Cadaveric temporal bone dissection in a temporal bone laboratory is a vital component in training safe, competent otorhinolaryngologists. Recent controversies pertaining to organ retention have resulted in a more limited supply of temporal bones. Consequently, current trainees are dissecting far fewer bones than their consultants. We discuss the establishment of a temporal bone laboratory in the Department of Anatomy in the University College Cork, from the timely preparation and preservation of the tissue to its disposal. Comparisons are drawn between our experience and that of the United States training schemes. The temporal bone laboratory in Cork is the only one in existence in Ireland. The exposure and experience obtained by registrars rotating through Cork, has resulted in noticeable improvements in their operative abilities. The temporal bone laboratory remains a core component to training. It is hoped that this article may facilitate other units overcoming obstacles to establish a temporal bone laboratory.