Otological Planning Software-OTOPLAN: A Narrative Literature Review

The cochlear implant (CI) is a widely accepted option in patients with severe to profound hearing loss receiving limited benefit from traditional hearing aids. CI surgery uses a default setting for frequency allocation aiming to reproduce tonotopicity, thus mimicking the normal cochlea. One emerging instrument that may substantially help the surgeon before, during, and after the surgery is a surgical planning software product developed in collaboration by CASCINATION AG (Bern, Switzerland) and MED-EL (Innsbruck Austria). The aim of this narrative review is to present an overview of the main features of this otological planning software, called OTOPLAN®. The literature was searched on the PubMed and Web of Science databases. The search terms used were "OTOPLAN", "cochlear planning software" "three-dimensional imaging", "3D segmentation", and "cochlear implant" combined into different queries. This strategy yielded 52 publications, and a total of 31 studies were included. The review of the literature revealed that OTOPLAN is a useful tool for otologists and audiologists as it improves preoperative surgical planning both in adults and in children, guides the intraoperative procedure and allows postoperative evaluation of the CI.

[Application of allogenous dural membrane (brefotissue DM) in surgical treatment of retraction pockets of the tympanic membrane]

INTRODUCTION

The tactics of treating patients with retraction pockets of the tympanic membrane is still debatable. When choosing surgical treatment, preference is given to the removal of the retraction pocket with simultaneous reconstruction of the posterior-upper wall of the external auditory canal (retraction area) with a cartilage or fascial flap, autologous bone, or a combination of the above tissues. Considering the well-known negative aspects of the use of all the mentioned grafts, there is a need to find new types of tissues to strengthen the retraction pocket. For example, dura mater brefotissue has good plastic properties, resistance to infection, is easy to prepare, store, and is cheaper than many allografts.

AIM

Evaluation of the possibility of using dura mater brefotissue in the surgical treatment of patients with retraction pockets of the tympanic membrane.

MATERIALS AND METHODS

The study included 52 patients who underwent surgery to eliminate the retraction pocket. All of them were divided into 2 groups. In the first - the main (n=25) cartilage of the auricle was used to seal the relaxed part of the tympanic membrane, in the second - the control (n=27) applied tissue of the dura mater. After 1, 3, 6 and 12 months, to assess the result of the intervention, all patients underwent otomicroscopy, audiometry with the calculation of the average sound conduction index for speech frequencies.

RESEARCH RESULTS

Fewer cases (4 patients out of 27) had difficulty in graft placement with the use of dura mater compared to the group where cartilage was used (9 patients out of 25). The average duration of graft placement was 8±0.5 minutes in the control group and 2±0.3 minutes in the main group. A stable morphological result was obtained in the group with the use of brefotissue in 26 patients (96%) and only in 20 patients (80%) with the use of cartilage. It is important to note that in the group with the use of brefotissue, in the early postoperative period, there was an increase in the air-bone interval, and 1 month after the operation, the average values increased by 10±0.5 dB. 12 months after the operation, the above parameters returned to preoperative.

CONCLUSION

The conducted study indicates that the dura mater brefotissue, having sufficient strength, the convenience of forming a given shape and placing it in the desired position, can be successfully used in the surgical treatment of patients with retraction pockets of the tympanic membrane.

Implantation of the Bonebridge BCI 602 after Mastoid Obliteration with S53P4 Bioactive Glass: A Safe Method of Treating Difficult Anatomical Conditions-Preliminary Results

This study presents the preliminary results of a new otosurgical method in patients after canal wall down (CWD) surgery; it involves the implantation of the Bonebridge BCI 602 implant after obliteration of the mastoid cavity with S53P4 bioactive glass. The study involved eight adult patients who had a history of chronic otitis media with cholesteatoma in one or both ears and who had had prior radical surgery. The mean follow-up period was 12 months, with routine follow-up visits according to the schedule. The analysis had two aspects: a surgical aspect in terms of healing, development of bacterial flora, the impact on the inner ear or labyrinth, recurrence of cholesteatoma, and possible postoperative complications (firstly, after obliteration of the mastoid cavity with S53P4 bioactive glass, then after implantation). The second was an audiological aspect which assessed audiometric results and the patient’s satisfaction based on questionnaires. During the follow-up period, we did not notice any serious postoperative complications. Studies demonstrated significantly improved hearing thresholds and speech recognition in quiet and noise using the Bonebridge BCI 602. Data collected after six months of use showed improved audiological thresholds and patient satisfaction. Based on the preliminary results, we believe that the proposed two-stage surgical method using bioactive glass S53P4 is a safe and effective way of implanting the Bonebridge BCI 602 in difficult anatomical conditions. This makes it possible to treat a larger group of patients with the device.

Conventional Microscopic Stapedotomy: An Obsolete Technique or Still the Gold Standard for the Management of Otosclerosis?

Background and objectives Clinical otosclerosis is a relatively common entity, accounting for 0.5%-2% of the general population. Otosclerosis is characterized by an abnormal bone formation in the temporal bone that eventually causes conductive hearing loss. Bilateral involvement is fairly common. Treatment can be either conservative with medications and a hearing aid, or surgical. Stapedotomy is considered, nowadays, the most effective surgical technique for the management of otosclerosis. The purpose of the present study is to present our long-term results with stapedectomy, the audiological outcome, as well as the complications encountered. Subjects and methods This is a retrospective single-centre study. All patients diagnosed with otosclerosis and treated operatively with a stapedotomy from January 2010 to December 2019 were included in the study. Demographic data, air and bone conduction thresholds, complications and length of the prosthesis were recorded.  Results The study included a total of 72 patients. The audiological results showed a statistically significant improvement in the air conduction thresholds in all the affected frequencies (p<0.001). Post-operative complications included deterioration or severe hearing loss up to 100 dB (n=1, 1.39%), loss or distortion of taste (n=4, 5.6%) and tinnitus (n=2, 2.8%). Conclusions Our results demonstrate that stapedotomy is an effective technique for the management of otosclerosis. Stapedotomy, when performed by an experienced surgeon, provides excellent outcomes, with limited complications.

Our Experience on Temporal Bone Fractures: Retrospective Analysis of 141 Cases

Temporal bone fractures are a common lesion of the base of the skull. The diagnosis and management of temporal bone fractures require a multidisciplinary approach. Variable clinical presentations may arise from such fractures, ranging from an asymptomatic course to very serious consequences. The aim of this study was to report our experience with a series of patients with temporal bone fractures and to propose a diagnostic/therapeutic algorithm. This study enrolled 141 patients, 96 (68.1%) males and 45 (31.9%) females, ranging in age from 20 to 60 (average age: 39 ± 4.1 years), with temporal bone fractures who were referred to Cardarelli Hospital between 2006 and 2018. The present paper presents a classification of temporal bone fractures and typical clinical sequelae and provides an illustration of their prognosis and treatment.

Iatrogenic patient injuries in otology during a 10-year period: review of national patient insurance charts

OBJECTIVE

To assess patient injury characteristics and contributing factors in otology.

METHODS

Data on the accepted patient-injury claims involving otorhinolaryngology (ORL), closed between 2001 and 2011, from the Finnish Patient Insurance Centre registry was retrieved. We included all injuries concerning otology, with evaluation and classification of their causes and types.

RESULTS

During the 10-year study period, a total of 44 claims were accepted as compensated patient injuries in otology. From a total of 233 patient injuries in all ORL, this amounted to 19%. In outpatient care, occurred 12 (27%) injuries and in surgical procedures 32 (73%). Five (11%) patients were children. Errors in surgical technique were identified as the primary cause of the injury in 22 (69%) operation-related cases. Failure to remove all auricular tampons or packing in postoperative control was a contributing factor in 4 (13%) injuries, a facial nerve was damaged in 9 (28%) operations, and in 12 (38%) patients, the injury resulted in severe hearing loss or deafness. Six patients (21%) needed one or more re-operations related to the injury, of which two were due to an incomplete primary operation.

CONCLUSION

Typical compensated patient injuries in operative otology resulted from common complications of common operations in high volume centres.

The chorda tympani degenerates during chronic otitis media: an electron microscopy study

CONCLUSION

Chorda tympani nerve specimens from ears with chronic inflammatory middle ear disease exhibit structural signs of degeneration. These correlate well with taste disturbance. Simultaneously, they exhibit signs of regeneration, which may explain the ability for taste recovery.

OBJECTIVES

The chorda tympani, the major taste nerve, runs uncovered through the middle ear cavity. This situation exposes it to various forms of middle ear pathology. A difference has been noticed regarding taste symptoms pre- and postoperatively between inflammatory and non-inflammatory diseases. The present study aimed to investigate ultrastructural changes of chorda tympani in different forms of inflammatory middle ear disease, such as chronic suppurative otitis media and cholesteatoma, as compared with normal.

METHODS

Five chorda tympani specimens were collected from healthy middle ears of patients subjected to surgery for acoustic neuroma, to be used as normal controls, and five from middle ears with chronic otitis media or cholesteatoma, where the nerve could not be saved during the operation. Light and electron microscopy were performed.

RESULTS

For all five nerves from diseased ears, microscopy showed a higher percentage of axon and myelin sheath degeneration than in the normal controls. Furthermore, three of the five also exhibited sprouting.

A new nasopharyngeal dynamic reference frame improves accuracy in navigated skull base targets

OBJECTIVE

We questioned whether the position of the dynamic reference frame (DRF) influences the application accuracy in electromagnetically navigated cranial procedures. A carrier for an electromagnetic DRF was developed, which could be fixed at the posterior edge of the vomer near the center of the head. This nasopharyngeal DRF was compared with a standard DRF fixed to the surface of the forehead.

METHODS

Image coordinates and real-world coordinates were co-registered and the total target error (TTE) was measured in the frontal and the lateral skull base of formalin fixed human head. At each anatomical site, 10 targets served for TTE determinations and 5 different fiducial combinations were used for registration.

RESULTS

With the nasopharyngeal DRF, lower TTE values (2.8 ± 1.4 mm; mean ± SD) were observed when compared with the forehead DRF (3.7 ± 2.8 mm; P = .004). TTEs of both anatomical sites investigated were significantly lower when using the nasopharyngeal DRF (frontal skull base 3.4 vs 2.1 mm, P = .005 and lateral skull base 3.9 vs 3.5 mm, P = .013) than with the standard forehead mounted one.

CONCLUSION

Positioning the DRF in the center of the head significantly improved the application accuracy of targets in the skull base with electromagnetic navigation by 25%.