Skull base osteomyelitis: clinical and radiologic analysis of a rare and multifaceted pathological entity.

Skull base osteomyelitis (SBO) is a potentially life-threatening inflammation of cranial base bony structures of variable origin. Criteria for diagnosis and treatment are still controversial. Demographics, predisposing factors, symptoms, imaging, and clinical, laboratory, histological, and microbiological data of patients managed for SBO at the University Hospital of Brescia (ASST Spedali Civili) between 2002 and 2017 were retrospectively reviewed. Patients were included in different etiological groups. The topographic distribution of magnetic resonance (MR) abnormalities was recorded on a bi-dimensional model of skull base, on which three different patterns of inflammatory changes (edematous, solid, or necrotic) were reported. In patients with a history of radiotherapy, the spatial distribution of SBO was compared with irradiation fields. The association between variables and etiological groups was verified with appropriate statistical tests. A classification tree analysis was performed with the aim of inferring a clinical-radiological diagnostic algorithm for SBO. The study included 47 patients, divided into 5 etiological groups: otogenic (n = 5), radio-induced (n = 16), fungal (n = 14), immune-mediated (n = 6), and idiopathic (n = 6). At MR, five types of topographical distribution were identified (central symmetric, central asymmetric, orbital apex, sinonasal, maxillary). In patients with a history of radiotherapy, the probability to develop SBO was significantly increased in areas receiving the highest radiation dosage. The analysis of patients allowed for design of a classification tree for the diagnosis of SBO. The integration of clinical and radiologic information is an efficient strategy to categorize SBO and potentially guide its complex management.

Cognitive function and quality of life in older adult patients with cochlear implants.

Objective: This study aimed to evaluate the benefits of cochlear implant (CI) on speech perception, quality of life (QoL), and cognitive function in profoundly deafened older adults.Design: Longitudinal and cross-sectional cohort study.Study sample: Participants in this study were CI recipients aged 65 years or older (experimental group), CI recipients aged 50 years or younger (control group 1), and normal-hearing participants aged 65 years or older (control group 2).Results: Speech perception significantly improved in both groups of implanted patients (preoperative vs. 1-year median [IQR] sentence recognition: older patients, 0 (0-20) vs. 90 (70-95), p = 0.001; younger patients, 35 (0-50) vs. 90 (80-100), p = 0.001). There were no significant differences in QoL (Glasgow Benefit Inventory) between younger and older patients (median [IQR] overall benefit score, 42 (31-64) vs. 53 (39-69), p = 0.2). Mini-Mental State Examination scores showed no significant differences between elderly CI recipients and normal-hearing participants (median [IQR], 28 (26-28) vs. 28 (27-29), p = 0.5).Conclusions: Cochlear implantation rehabilitation allows the profoundly deafened older adult to lead a QoL comparable to that of a younger patient. The correlation between hearing restoration and cognitive function preservation in older adults suggest a possible role for CI as a useful resource in limiting age-related cognitive decline.

Endoscopic transcanal tympanoplasty type I in children: Evolving experience in tragus perichondrium vs. acellular porcine small intestinal sub-mucosa grafts.

OBJECTIVES: Endoscopic trans-canal tympanoplasty type I (ETT) is gradually diffusing worldwide. It mainly allows less invasive surgery in children with respect to a microscope approach by avoiding post-auricular access. The aim of this study is to illustrate our experience in endoscopic reconstruction of tympanic membrane, using autologous tragus perichondrium (TP) and non-autologous acellular porcine small intestinal sub-mucosa (SIS) as grafts. METHODS: Between January 2011 and December 2020, the results of a prospective non-randomized series of consecutive ETT were analyzed. The primary outcome was closure rate at 6 months and secondary outcomes are closure rates associated with age, size of perforation, type of perforation and middle ear status, presence of myringosclerosis, type of graft, status of contralateral ear, adenoidectomy and pre-postoperative ABG change. Statistical analysis was performed using the SPSS statistical package. RESULTS: One hundred and sixteen consecutive procedures, mean age 9.4 years (range 4-17 years), were evaluated. TP and SIS grafts were used in 65 (56%) and 51 (44%) procedures, respectively. Mean duration of surgical procedure was 53 ± 21 min for SIS and 77 ± 18 min for TP (P = 0.001) Total graft intake was 82.8%; TP and SIS intake were 86.2% and 78.4% (P = 0.3), respectively. Graft intake w.r.t. in age stratified age groups was not statistically significant. Average preoperative and postoperative air-bone gap was 12.1 ± 7.6 dB and 5.5 ± 3.8 dB, respectively (P = 0.001). The difference in closure rates was not significant. Neither intra- nor postoperative complications were observed. CONCLUSIONS: In children, ETT is an applicable and less invasive technique compared to the microscope and offers less morbidity. The use of SIS contributes additional less invasiveness to endoscopic surgery by avoiding tragus harvesting with a comparable success rate and granting significantly less surgical duration.

Presentation, Management, and Hearing Outcomes of Labyrinthine Fistula Secondary to Cholesteatoma: A Systematic Review and Meta-analysis.

OBJECTIVE: The current study systematically reviewed the literature to compare auditory outcomes of patients treated for labyrinthine fistula (LF) based on characteristics of disease and surgical management. DATABASES REVIEWED: PubMed, Scopus, Web of Science. METHODS: Original series (at least five cases) published from 2000 reporting management and hearing results of LF secondary to cholesteatoma were included. Proportion and odds-ratio (OR) meta-analyses were conducted through inverse variance random-effects models based on logit transformation. RESULTS: The prevalence of LF is estimated to be 7% (95% confidence interval [CI], 5-9%). Fistulae involving the lateral semicircular canal (90%; 95% CI, 87-93%) and larger than 2 mm (53%; 95% CI, 43-64%) were common, whereas membranous involvement was less frequent (20%; 95% CI, 12-30%). Complete removal of the cholesteatoma matrix overlying the LF was mostly applied. Bone conduction (BC) preservation was frequently achieved (81%; 95% CI, 76-85%); new-onset postoperative anacusis was rarely reported (5%; 95% CI, 4-8%). A higher chance of BC preservation was associated with sparing the perilymphatic space (OR, 4.67; 95% CI, 1.26-17.37) or membranous labyrinth (OR, 4.56; 95% CI, 2.33-8.93), exclusive lateral semicircular canal involvement (OR, 3.52; 95% CI, 1.32-9.38), smaller size (<2 mm; OR, 3.03; 95% CI, 1.24-7.40), and intravenous steroid infusion (OR, 7.87; 95% CI, 2.34-26.42). CONCLUSION: LF occurs in a significant proportion of patients with cholesteatoma. In the past two decades, complete removal of the cholesteatoma matrix followed by immediate sealing has been favored, supported by the high proportion of BC preservation. Hearing preservation depends primarily on characteristics of the LF, and specific surgical strategies should be pursued. Intraoperative and postoperative intravenous steroid infusion is recommended.

Exploratory tympanotomy in conductive hearing loss with normal pre-operative investigations.

Objective: To investigate whether patients with conductive hearing loss (CHL) and normal preoperative investigations may benefit from exploratory tympanotomy (ET) and tailored treatment performed according to intraoperative findings. Methods: Patients treated with ET for CHL with normal pre-operative otoscopy, tympanometry and CT scan from 2011 to 2019 were reviewed. Data regarding demographics, audiometry, intraoperative findings and surgery were collected and analysed to assess if they can predict post-operative air bone gap (ABG) closure and patient satisfaction. Results: Forty-eight cases were included. Mean ABG significantly reduced (p < 0.001) from preoperative (38.4 dB) to postoperative (14.8 dB). Post-operative ABG closure within 10 dB was observed in 20 cases (41.7%). Overall satisfaction was reported in 60% of cases. Stapes fixation was the most common diagnosis (47.9%) and significantly associated with lower post-operative ABG and higher satisfaction. Conclusions: In CHL with normal pre-operative investigations, ET represents the mainstay of treatment, even if audiological outcomes may widely vary. Intraoperative finding of stapes fixation (thus stapedotomy) ensures the best audiological and satisfaction outcomes.

Early-Career Surgical Practice for Cerebellopontine Angle Tumors in the Era of Radiosurgery.

We analyzed the outcomes of patients with large cerebellopontine angle (CPA) tumors treated by a skull-base team in which two surgeons (one neurosurgeon and one otological surgeon) were in the beginning of their careers (<40 years old). Data of patients operated on between April 2012 and March 2016 were reviewed. All factors related to surgical training were considered. Thirty-one patients had vestibular schwannomas, while 26 had meningiomas. Mean tumor diameter was 30.6 mm (range, 23-49 mm) for schwannomas and 35 mm (range, 22-51 mm) for meningiomas. Satisfactory postoperative facial nerve function (House-Brackmann's grade I or II) was achieved in 20 (64.5%) schwannoma patients and 21 (80.7%) meningioma patients. Gross total and near-total resections (residual tumor < 5 mm) were achieved in 21 (67.7%) and 9 (29%) schwannoma patients, respectively. Gross total resection (Simpson's grade II) was achieved in 18 (69.2%) meningioma patients. In both groups, the retrosigmoid approach was the most common approach. Regarding surgical training of the two younger surgeons, during the residency period, they attended high-volume centers for CPA tumors. Application of microsurgical techniques was systematically applied from the beginning of their personal series in every intracranial pathology case. During the first 2 years of the series, they were supervised by more experienced surgeons and followed a stepwise sharing of increasingly difficult surgical phases; by comparing results of this period with the last 2 years of the series, where they acquired a complete autonomy, no relevant difference was detected. Our results suggest that young surgeons may achieve good results even at the beginning of their careers, if specific conditions related to training and mentorship are met.

Transnasal Endoscopic and Lateral Approaches to the Clivus: A Quantitative Anatomic Study.

BACKGROUND: Transnasal endoscopic approaches to the clivus have been established recently. Comparative analyses with classic lateral approaches are limited. In this study, we compared transnasal endoscopic and lateral approaches to the clivus, quantifying the exposure and working volume of each approach in the anatomy laboratory. METHODS: High-resolution computed tomography scans were performed on 5 injected specimens (10 sides). In each specimen, transnasal endoscopic approaches (i.e., paraseptal, transrostral, extended transrostral, transethmoidal, and extended transclival without and with intradural hypophysiopexy) and lateral approaches (i.e., retrosigmoid, far-lateral, presigmoid retrolabyrinthine and translabyrinthine) to the clivus were performed. An optic neuronavigation system and dedicated software (ApproachViewer; Guided Therapeutics Program, University Health Network, Toronto, Ontario, Canada) were used to quantify the working volume and exposed clival area of each approach. Statistical evaluation was performed with the Kruskal-Wallis test and Steel-Dwass-Critchlow-Fligner post hoc test. RESULTS: Endoscopic transnasal transclival approaches showed higher working volume and larger clival exposure compared with lateral approaches. Incremental volumetric values were evident for transnasal approaches; presigmoid approaches provided less working volume than retrosigmoid approaches. A transnasal transclival approach with hypophysiopexy provided significant exposure of the upper clivus (84.4%). The transrostral approach was the first transnasal approach providing satisfactory access to the midclivus (66%); retrosigmoid and far-lateral approaches provided exposure of approximately one half of the midclivus. The lower clivus was optimally exposed with endoscopic transclival approaches (83%), whereas access to this region was limited with lateral approaches. CONCLUSIONS: This quantitative anatomic study shows that endoscopic transnasal approaches to the clivus provide a larger working volume and wider exposure of the clivus compared with lateral approaches.

Spontaneous tegmen defect and semicircular canal dehiscence: same etiopathogenic entity?

OBJECTIVES: To describe the clinical and radiologic features of associated spontaneous tegmen defects (STDs) with semicircular canal dehiscences (SCCDs) and to postulate a novel etiopathogenic hypothesis of these pathologic conditions. METHODS: Medical records of all patients with surgically confirmed STD between 2001 and May 2010 were reviewed. We excluded all secondary tegmen defects. Clinical, audiological, and radiologic data were analyzed. RESULTS: Twenty-three patients matched the inclusion criteria. Semicircular canal dehiscence was associated to STD in 13 patients. Of these patients, 12 (95%) had protruding superior semicircular canals in the middle cranial fossa versus only 3 (30%) of 10 patients for the nondehiscent cases. Twenty-two patients complained of hearing loss. Cerebrospinal fluid leak was found in 13 patients. Four patients had history of meningitis. Vestibular symptoms were present in 8 patients. CONCLUSION: This is the largest series of reported coexistence of STD and SCCD in the literature. Protrusion of the superior semicircular canal in the middle cranial fossa is probably an additional factor underlying STD and SCCD etiopathogeny. Semicircular canal dehiscence should always be looked for when STD is present.

Cochlear reimplantations: technical and surgical failures.

CONCLUSION: Cochlear implant surgeons should have a good knowledge of how to diagnose device failures and how to deal with medical complications related to cochlear implantation. Electrode array misplacement may be due to unidentified inner ear malformation. Use of peroperative telemetry and radiographic examination should help to avoid such complications. OBJECTIVES: To review our experience of cochlear implant revision surgery and to compare our series to the literature. To report two cases of electrode array misplacement into the vestibular system and to discuss how to prevent this complication. SUBJECTS AND METHODS: This was a retrospective review of cochlear implant revision surgery in a tertiary reference center. RESULTS: Of 487 cochlear implantations, 3.8% of adults and 4.5% of children underwent a revision surgery. The mean time to device failure was 7.6 years in children and 1.5 year in adults. Causes of revision were seven hard failures, four soft failures, and nine medical reasons. Among the medical reasons, four patients had skin flap infection associated with an extended endaural approach. Audiologic performances were stable or improved following reimplantation in 90% of cases. We had two cases of electrode array misplaced into the vestibular system.

Reliability of high-resolution CT scan in diagnosis of otosclerosis.

OBJECTIVE: To assess the reliability of high-resolution computed tomographic scan (HRCT scan) for the diagnosis of otosclerosis and to determine its usefulness to predict hearing deterioration and surgical difficulties. STUDY DESIGN: Prospective study. SETTING: Tertiary reference center. PATIENTS: Two hundred nine ears (200 patients) presenting progressive conductive hearing loss with normal tympanic membrane, abnormal stapedial reflex, and scheduled for stapes surgery. The mean age was 47.3 years. INTERVENTION: All patients underwent HRCT scan before surgery (slice thickness of 0.6 to 1 mm). Stapedotomy was performed in 99% of cases. MAIN OUTCOME MEASURES: High-resolution computed tomographic scan results were categorized as positive, doubtful, or negative. We classified a CT scan as positive for otosclerosis when a hypodense focus was seen around the otic capsule. Preoperative and postoperative air- and bone-conduction thresholds were collected. RESULTS: Of 209 HRCT scans, 84.2% were classified positive, 8.6% doubtful, and 7.2% negative. In all patients with positive CT scan, otosclerosis was confirmed in surgery. Among 15 negative cases, we found 4 minor malformations and 1 fracture of the stapes. Footplate incidents (mobilized, floating, or fractured footplate; 5.3%) occurred significantly more frequently when an HRCT scan was negative or doubtful (p = 0.05). Mean preoperative air-bone gap was 27.7 dB (standard deviation, 10). Mean postoperative air-bone gap was within 10 dB in 65% and within 20 dB in 92% of cases. Greater than 10 dB deterioration of bone-conduction thresholds occurred in 2% of cases. Mean preoperative and postoperative bone-conduction thresholds were significantly lower in cases of round window obliteration, pericochlear, or internal auditory canal hypodensities (p < 0.005 and p < 0.0001, respectively). CONCLUSION: In our series, the sensitivity of HRCT scan to otosclerosis was 95.1%. Hypodense otosclerotic foci were mostly localized at the anterior part of footplate. Negative or doubtful cases were associated with the highest incidence of stapes footplate complications. Foci involving otic capsule, internal auditory canal, or round window led to a significantly higher risk of sensorineural hearing loss.