The phenotypic and genetic effects of drought-induced stress on wood specific conductivity and anatomical properties in white spruce seedlings, and relationships with growth and wood density.

Drought frequency and intensity are projected to increase with climate change, thus amplifying stress on forest trees. Resilience to drought implicates physiological traits such as xylem conductivity and wood anatomical traits, which are related to growth and wood density. Integrating drought-stress response traits at the juvenile stage into breeding criteria could help promote the survival of planted seedlings under current and future climate and thus, improve plantation success. We assessed in greenhouse the influence of drought-induced stress on 600 two-year-old white spruce (Picea glauca) seedlings from 25 clonal lines after two consecutive growing seasons. Three levels of drought-induced stress were applied: control, moderate and severe. Seedlings were also planted at a 45° angle to clearly separate compression from normal wood. We looked at the phenotypic and genetic effects of drought stress on xylem specific hydraulic conductivity, lumen diameter, tracheid diameter and length, and the number of pits per tracheid in the normal wood. We detected no significant effects of drought stress except for tracheid length, which decreased with increasing drought stress. We found low to high estimates of trait heritability, which generally decreased with increasing drought stress. Genetic correlations were higher than phenotypic correlations for all treatments. Specific conductivity was genetically highly correlated positively with lumen diameter and tracheid length under all treatments. Tracheid length and diameter were always negatively correlated genetically, indicating a trade-off in resource allocation. Moderate to high genetic correlations sometimes in opposite direction were observed between physico-anatomical and productivity traits, also indicating trade-offs. A large variation was observed among clones for all physico-anatomical traits, but clonal ranks were generally stable between control and drought-induced treatments. Our results indicate the possibility of early screening of genetic material for desirable wood anatomical attributes under normal growing conditions, thus allowing to improve the drought resilience of young trees.

Impacts of spruce budworm defoliation on the habitat of woodland caribou, moose, and their main predators.

Forest logging has contributed to the decline of several woodland caribou populations by causing the fragmentation of mature coniferous stands. Such habitat alterations could be worsened by spruce budworm (SBW) outbreaks. Using 6201 vegetation plots from provincial inventories conducted after the last SBW outbreak (1968-1992) in boreal forests of Québec (Canada), we investigated the influence of SBW-caused tree defoliation and mortality on understory vegetation layers relevant to woodland caribou and its main predators. We found a positive association between severe outbreaks and the cover of most groups of understory plant species, especially in stands that were dominated by balsam fir before the outbreak, where a high canopy openness particularly benefited relatively fast-growing deciduous plants. Such increases in early successional vegetation could provide high-quality forage for moose, which is likely to promote higher wolf densities and increase predation pressure on caribou. SBW outbreaks may thus negatively affect woodland caribou by increasing predation risk, the main factor limiting caribou populations in managed forests. For the near future, we recommend updating the criteria used to define critical caribou habitat to consider the potential impacts of spruce budworm defoliation.

Gentamicin Vestibulotoxicity: Further Insights From a Large Clinical Series.

OBJECTIVE: To review insights gained from a 21-year experience with gentamicin-induced vestibulotoxicity including differences in vestibulotoxicity between single daily dosing (SDD) and multiple daily dosing (MDD) regimens. STUDY DESIGN: Retrospective case series. SETTING: Tertiary care center. PATIENTS: Patients with gentamicin vestibulotoxicity referred to the Hertz Multidisciplinary Neurotology Clinic between January 1993 and September 2014. INTERVENTION: None. MAIN OUTCOME MEASURES: Spectrum of vestibular dysfunction measured using videonystagmography, vestibular evoked myogenic potentials, video head impulse testing, and magnetic scleral search coil testing. RESULTS: Of 53 patients with gentamicin-induced vestibulotoxicity, 24 received SDD and 29 received MDD treatment. The most common indications for treatment were sepsis, endocarditis, and osteomyelitis. Angular acceleration receptor function (semicircular canals) was more commonly affected than linear acceleration receptor function (otolithic organ of the saccule; 100% vs. 62%). A significant proportion of patients (53%) developed vestibulotoxicity in the absence of nephrotoxicity and 40% experienced vestibulotoxicity in a delayed fashion up to 10 days posttreatment cessation (mean 3.9 ±â€Š0.7). Therapeutic monitoring did not necessarily prevent delayed vestibulotoxicity. Nephrotoxicity was less common for SDD compared with MDD (60% vs. 35%, p = 0.01). However, the SDD group experienced vestibulotoxicity at a lower cumulative dose (6.3 vs. 7.0 g, p = 0.04) and shorter duration of therapy (20.7 vs 29.4 d, p = 0.02). CONCLUSIONS: Our study further highlights important insights regarding gentamicin-induced vestibulotoxicity. While SDD is associated with decreased risk for nephrotoxicity compared with MDD, it confers a higher risk for vestibulotoxicity.

Interdisciplinary integration of nursing and psychiatry (INaP) improves dizziness-related disability.

OBJECTIVES/HYPOTHESIS: The traditional medical care model of "assess and refer" in a sequential fashion fails to recognize the complexities that arise due to overlapping physical and psychiatric comorbidities experienced by patients with chronic dizziness or imbalance, thus resulting in inadequate treatment outcomes. We aimed to evaluate the impact of a novel interdisciplinary approach to care that integrates nursing and psychiatry (INaP) on dizziness-related disability. STUDY DESIGN: Retrospective cohort study. METHODS: We compared the change in clinical assessment scores (i.e., Dizziness Handicap Inventory [DHI], Dizziness Catastrophizing Scale) at approximately 8 months follow-up between those who did (INaP+) and did not receive INaP (INaP-). Data from 229 patients with dizziness or imbalance referred to an interdisciplinary neurotology clinic in Toronto, Ontario, Canada were acquired from August 2012 to December 2016 and January 2011 to December 2013 for the INaP+ and INaP- groups, respectively. RESULTS: A mean group difference in the percentage change in DHI scores was found, with greater reductions in dizziness-related disability in the INaP+ group (n = 121) versus the INaP- group (n = 108). This remained significant after controlling for age, gender, baseline illness severity, and duration between baseline and follow-up visits. CONCLUSIONS: The novel interdisciplinary approach of incorporating INaP appears to be more effective than interdisciplinary care without INaP in reducing dizziness-related disability in patients with chronic dizziness or imbalance. Clinical settings should consider the addition of INaP to achieve better patient outcomes. Future studies are required to test the hypothesis that INaP is more efficient and cost-effective than the traditional model of care. LEVEL OF EVIDENCE: 3 Laryngoscope, 130:1800-1804, 2020.

Interdisciplinary integration of nursing and psychiatry (INaP) for the treatment of dizziness.

OBJECTIVES: The traditional medical care model of "assess and refer" requires revamping to address the multifaceted needs of patients with chronic dizziness and imbalance by adopting an interdisciplinary approach to care that integrates nursing and psychiatry (INaP). We aim to present a novel interdisciplinary approach that incorporates INaP in the care of patients with chronic dizziness and imbalance. METHODS: Presentation of an interdisciplinary model of care that incorporates INaP provided at the Toronto General Hospital in Toronto, Canada. RESULTS: Interdisciplinary care incorporating INaP, which includes the provision of support from an interdisciplinary health care team (ie, neurotologist, neurologist, psychiatrist, physiotherapist, and nurse clinician), psychoeducation about the interaction between chronic dizziness and psychiatric comorbidities, and ongoing access to medical and psychosocial assessment and intervention, addresses the physical and emotional aspects of patients' experience with chronic dizziness. CONCLUSIONS: The novel comprehensive interdisciplinary approach incorporating INaP may be more effective than interdisciplinary care without INaP in improving clinical outcomes in patients with chronic dizziness. In the subsequent study, we present data comparing patients treated for chronic dizziness and imbalance with and without the integration of INaP in an interdisciplinary setting. LEVEL OF EVIDENCE: 5 Laryngoscope, 130:1792-1799, 2020.

BalanCI: Head-Referenced Cochlear Implant Stimulation Improves Balance in Children with Bilateral Cochleovestibular Loss.

INTRODUCTION: To determine the impact of a head-referenced cochlear implant (CI) stimulation system, BalanCI, on balance and postural control in children with bilateral cochleovestibular loss (BCVL) who use bilateral CI. METHODS: Prospective, blinded case-control study. Balance and postural control testing occurred in two settings: (1) quiet clinical setting and (2) immersive realistic virtual environment (Challenging Environment Assessment Laboratory [CEAL], Toronto Rehabilitation Institute). Postural control was assessed in 16 and balance in 10 children with BCVL who use bilateral CI, along with 10 typically developing children. Children with neuromotor, cognitive, or visual deficits that would prevent them from performing the tests were excluded. Children wore the BalanCI, which is a head-mounted device that couples with their CIs through the audio port and provides head-referenced spatial information delivered via the intracochlear electrode array. Postural control was measured by center of pressure (COP) and time to fall using the WiiTM (Nintendo, WA, USA) Balance Board for feet and the BalanCI for head, during the administration of the Modified Clinical Test of Sensory Interaction in Balance (CTSIB-M). The COP of the head and feet were assessed for change by deviation, measured as root mean square around the COP (COP-RMS), rate of deviation (COP-RMS/duration), and rate of path length change from center (COP-velocity). Balance was assessed by the Bruininks-Oseretsky Test of Motor Proficiency 2, balance subtest (BOT-2), specifically, BOT-2 score as well as time to fall/fault. RESULTS: In the virtual environment, children demonstrated more stable balance when using BalanCI as measured by an improvement in BOT-2 scores. In a quiet clinical setting, the use of BalanCI led to improved postural control as demonstrated by significant reductions in COP-RMS and COP-velocity. With the use of BalanCI, the number of falls/faults was significantly reduced and time to fall increased. CONCLUSIONS: BalanCI is a simple and effective means of improving postural control and balance in children with BCVL who use bilateral CI. BalanCI could potentially improve the safety of these children, reduce the effort they expend maintaining balance and allow them to take part in more complex balance tasks where sensory information may be limited and/or noisy.

Long-Term Late Toxicity, Quality of Life, and Emotional Distress in Patients With Nasopharyngeal Carcinoma Treated With Intensity Modulated Radiation Therapy.

PURPOSE: To report long-term (>4 years) toxicity and quality of life (QoL) among patients with nasopharyngeal carcinoma (NPC) treated with intensity modulated radiation therapy (IMRT) in a nonendemic center. METHODS AND MATERIALS: A cross-sectional cohort study enrolled patients with NPC who were disease-free and ≥4 years after IMRT ± chemotherapy. Physician-reported adverse events (Common Terminology Criteria for Adverse Events, version 4.03) and patient-reported QoL (Functional Assessment of Cancer Therapy-Head and Neck, Functional Assessment of Chronic Illness Therapy-Fatigue), utilities (EuroQOL-5D), head and neck symptoms (MD Anderson Symptom Inventory-Head and Neck), and emotional distress (Hospital Anxiety and Depression Scale) were collected. Consenting patients also underwent endocrine screening and audiometry. RESULTS: Among 107 patients enrolled, median age at enrollment and time since treatment were 57 (32-81) and 7.5 years (4.2-11.1), respectively. Most patients (99%) received 70 Gy in 35 fractions; the majority (93%) received concurrent chemotherapy. Mean scores for the Functional Assessment of Cancer Therapy-Head and Neck, Functional Assessment of Chronic Illness Therapy-Fatigue, and EuroQOL-5D were 105.0 (46-148), 116.6 (44-160), and 0.85 (0.29-1.00), respectively. Dry mouth, mucus, swallowing/chewing, memory, and teeth/gum problems were scored highest on the MD Anderson Symptom Inventory-Head and Neck; mean symptom severity and symptom interference scores were 2.3 and 2.4, respectively. Grade 3 or higher physician-reported adverse events were noted in 50 patients (47%), most frequently hearing problems (46, 43%). Audiometry revealed significant bilateral hearing loss (grade ≥3) in 68 patients (72%). Depression (25%), anxiety (37%), and fatigue (28%) were common and strongly correlated with QoL. Most patients (69%) developed hypothyroidism; 1 patient (1%) developed pituitary dysfunction requiring hormone replacement. V50 >90 and V45 >99 to the thyroid correlated with significantly higher rates of hypothyroidism. CONCLUSIONS: Despite the implementation of IMRT, survivors of NPC still experience many physical symptoms that affect long-term QoL many years after treatment. Depression, anxiety, and fatigue remain common in long-term survivors and are highly correlated with QoL.

Association Between Catastrophizing and Dizziness-Related Disability Assessed With the Dizziness Catastrophizing Scale.

Importance: Catastrophizing is a maladaptive thought process that involves irrational fear and worry about anticipated or actual symptoms. Although clinically relevant, the role of catastrophizing in patients with chronic dizziness or imbalance has not yet been explored to our knowledge. Objectives: To validate a measure of dizziness catastrophizing and to assess its association with dizziness-related disability compared with other negative affect constructs (eg, anxiety and depression). Design, Setting, and Participants: For this retrospective medical record review, the Dizziness Catastrophizing Scale (DCS), a dizziness-specific catastrophizing assessment tool, was adapted from the previously validated Pain Catastrophizing Scale. Psychometric evaluation of the DCS was performed. In addition, the associations of dizziness catastrophizing and positive and negative affectivity with dizziness-related disability were assessed using structural equation modeling and regression analyses. Data were collected using a retrospective medical record review from April 27, 2010, to June 25, 2014. The dates of analysis were June 3 to August 15, 2017. The setting was the Multidisciplinary Neurotology Clinic at the Toronto General Hospital (Toronto, Ontario, Canada). Participants were 457 adult outpatients with dizziness or imbalance who were referred to the clinic. Main Outcomes and Measures: Psychometric properties of the DCS and its association with dizziness-related disability, as measured with the Dizziness Handicap Inventory. Results: Among 457 patients (mean [SD] age, 53.4 [15.4] years; 154 [33.7%] male), the DCS demonstrated good convergent (r = 0.78, P < .001) and discriminant validity (r = -0.40, P < .001) with the negative and positive affectivity, respectively; internal consistency (α = .95); and test-retest reliability (intraclass correlation coefficient, 0.92; P < .001 at the 95% CI). An exploratory dimension reduction analysis revealed a single latent component of the DCS. The results of the structural equation modeling and regression analyses revealed that dizziness catastrophizing, although associated with negative affectivity (eg, symptoms of anxiety and depression), was independently associated with dizziness-related disability (standardized ß = 0.378; P < .001). Furthermore, a strong association was found between catastrophizing and dizziness-related disability across different dizziness-related diagnoses (r ≥ 0.6; P < .001). Conclusions and Relevance: In this study, the DCS was a valid and reliable measure for evaluating catastrophic thinking in patients with dizziness, which was independently associated with dizziness-related disability. Future studies should investigate the influence of alleviating symptoms of catastrophizing on functional outcomes in patients with dizziness or imbalance, the results of which will help guide novel approaches to the clinical care of patients with chronic dizziness.

Consultation diagnoses and procedures billed among recent graduates practicing general otolaryngology - head & neck surgery in Ontario, Canada.

BACKGROUND: An analysis of the scope of practice of recent Otolaryngology - Head and Neck Surgery (OHNS) graduates working as general otolaryngologists has not been previously performed. As Canadian OHNS residency programs implement competency-based training strategies, this data may be used to align residency curricula with the clinical and surgical practice of recent graduates. METHODS: Ontario billing data were used to identify the most common diagnostic and procedure codes used by general otolaryngologists issued a billing number between 2006 and 2012. The codes were categorized by OHNS subspecialty. Practitioners with a narrow range of procedure codes or a high rate of complex procedure codes, were deemed subspecialists and therefore excluded. RESULTS: There were 108 recent graduates in a general practice identified. The most common diagnostic codes assigned to consultation billings were categorized as 'otology' (42%), 'general otolaryngology' (35%), 'rhinology' (17%) and 'head and neck' (4%). The most common procedure codes were categorized as 'general otolaryngology' (45%), 'otology' (23%), 'head and neck' (13%) and 'rhinology' (9%). The top 5 procedures were nasolaryngoscopy, ear microdebridement, myringotomy with insertion of ventilation tube, tonsillectomy, and turbinate reduction. Although otology encompassed a large proportion of procedures billed, tympanoplasty and mastoidectomy were surprisingly uncommon. CONCLUSION: This is the first study to analyze the nature of the clinical and surgical cases managed by recent OHNS graduates. The findings demonstrated a prominent representation of 'otology', 'general' and 'rhinology' based consultation diagnoses and procedures. The data derived from the study needs to be considered as residency curricula are modified to satisfy competency-based requirements.

Vestibular stimulation improves insight into illness in schizophrenia spectrum disorders.

Impaired insight into illness (IMP-INS) is common among individuals with schizophrenia spectrum disorders (SSD), contributing to medication nonadherence and poor clinical outcomes. Caloric vestibular simulation (CVS) is typically used to assess peripheral vestibular system function. Left cold CVS is also a transiently effective treatment for IMP-INS and hemineglect secondary to right brain hemisphere stroke, and possibly for IMP-INS and mood stabilization in patients with SSD. Participants with SSD and moderate-to-severe IMP-INS participated in an exploratory double blind, crossover, randomized controlled study of the effects of CVS on IMP-INS. Participants sequentially received all experimental conditions-left cold (4°C), right cold, and body temperature/sham CVS-in a random order. Repeated measures ANOVA were performed to compare changes in IMP-INS, mood and positive symptom severity pre and 30min post CVS. A significant interaction was found between CVS condition, time, and body temperature nystagmus peak slow phase velocity (PSPV) for IMP-INS, indicating that single session left cold CVS transiently improved IMP-INS while right cold CVS may have worsened IMP-INS, particularly in participants with greater vestibular reactivity (i.e. higher PSPV) to body temperature CVS. The procedure's effectiveness is attributed to stimulation of underactive right hemisphere circuits via vestibular nuclei projections to the contralateral hemisphere.

Processes driving short-term temporal dynamics of small mammal distribution in human-disturbed environments.

As the impact of anthropogenic activities intensifies worldwide, an increasing proportion of landscape is converted to early successional stages every year. To understand and anticipate the global effects of the human footprint on wildlife, assessing short-term changes in animal populations in response to disturbance events is becoming increasingly important. We used isodar habitat selection theory to reveal the consequences of timber harvesting on the ecological processes that control the distribution dynamics of a small mammal, the red-backed vole (Myodes gapperi). The abundance of voles was estimated in pairs of cut and uncut forest stands, prior to logging and up to 2 years afterwards. A week after logging, voles did not display any preference between cut and uncut stands, and a non-significant isodar indicated that their distribution was not driven by density-dependent habitat selection. One month after harvesting, however, juvenile abundance increased in cut stands, whereas the highest proportions of reproductive females were observed in uncut stands. This distribution pattern appears to result from interference competition, with juveniles moving into cuts where there was weaker competition with adults. In fact, the emergence of source-sink dynamics between uncut and cut stands, driven by interference competition, could explain why the abundance of red-backed voles became lower in cut (the sink) than uncut (the source) stands 1-2 years after logging. Our study demonstrates that the influences of density-dependent habitat selection and interference competition in shaping animal distribution can vary frequently, and for several months, following anthropogenic disturbance.

Large-Scale Variations in Lumber Value Recovery of Yellow Birch and Sugar Maple in Quebec, Canada.

Silvicultural restoration measures have been implemented in the northern hardwoods forests of southern Quebec, Canada, but their financial applicability is often hampered by the depleted state of the resource. To help identify sites most suited for the production of high quality timber, where the potential return on silvicultural investments should be the highest, this study assessed the impact of stand and site characteristics on timber quality in sugar maple (Acer saccharum Marsh.) and yellow birch (Betula alleghaniensis Britt.). For this purpose, lumber value recovery (LVR), an estimate of the summed value of boards contained in a unit volume of round wood, was used as an indicator of timber quality. Predictions of LVR were made for yellow birch and sugar maple trees contained in a network of more than 22000 temporary sample plots across the Province. Next, stand-level variables were selected and models to predict LVR were built using the boosted regression trees method. Finally, the occurrence of spatial clusters was verified by a hotspot analysis. Results showed that in both species LVR was positively correlated with the stand age and structural diversity index, and negatively correlated with the number of merchantable stems. Yellow birch had higher LVR in areas with shallower soils, whereas sugar maple had higher LVR in regions with deeper soils. The hotspot analysis indicated that clusters of high and low LVR exist across the province for both species. Although it remains uncertain to what extent the variability of LVR may result from variations in past management practices or in inherent site quality, we argue that efforts to produce high quality timber should be prioritized in sites where LVR is predicted to be the highest.

Ménière's Syndrome or Disease: Time Trends in Management and Quality of Evidence Over the Last Two Decades.

OBJECTIVE: To evaluate the evidence and trends in published literature on the treatment of Ménière's syndrome or disease (MS/D) by comparing studies published in the last two decades. DATA SOURCES: A literature search was performed on AMED, EMBASE, HMIC, MEDLINE, PsycINFO, BNI, CINAHL, HEALTH BUSINESS ELITE, CENTRAL and Cochrane Ear, Nose and Throat disorders groups trials register using a combination of MeSH. The date of last search was October 2014. STUDY SELECTION AND DATA EXTRACTION: Two hundred five studies (104 in decade I and 101 in decade II) were evaluated to report trends in the management of this condition, the differing levels of evidence published for each treatment modality, evaluate whether the guidelines published by the AAOHNS-Committee on Hearing and Equilibrium had been correctly employed, and whether the randomized controlled trials (RCTs) were compliant with the CONSORT guidelines. RESULTS: The number of published RCTs almost tripled from decade I (1994-2003) to decade II (2004-2103). There was a significant decline in the use of surgical intervention (p = 0.013); however, the number of studies involving the use of intratympanic injection remained largely unchanged. There was a shift in the level of evidence in published studies; studies with level 1 evidence tripled from decade I to II (4.8 to 17.8%, respectively) (p = 0.03); however, compliance with the AAOHNS-CHE criteria for reporting treatment outcomes and the CONSORT checklist was still poor. CONCLUSION: Although the evidence base on published literature on MS/D has improved over the last decade with an increase in emphasis on RCTs and quality of life (QoL) studies, a significant number of studies failed to follow AAOHNS-CHE criteria for reporting treatment outcome and the CONSORT criteria for reporting RCTs.

The round window region and contiguous areas: endoscopic anatomy and surgical implications.

The round window region is a critical area of the middle ear; the aim of this paper is to describe its anatomy from an endoscopic perspective, emphasizing some structures, the knowledge of which could have important implications during surgery, as well as to evaluate what involvement cholesteatoma may have with these structures. Retrospective review of video recordings of endoscopic ear surgeries and retrospective database review were conducted in Tertiary university referral center. Videos from endoscopic middle ear procedures carried out between June 2010 and September 2012 and stored in a shared database were reviewed retrospectively. Surgeries in which an endoscopic magnification of the round window region and the inferior retrotympanum area was performed intraoperatively were included in the study. Involvement by cholesteatoma of those regions was also documented based on information obtained from the surgical database. Conformation of the tegmen of the round window niche may influence the surgical view of round window membrane. A structure connecting the round window area to the petrous apex, named the subcochlear canaliculus, is described. Cholesteatoma can invade the round window areas in some patients. Endoscopic approaches can guarantee a very detailed view and allow the exploration of the round window region. Exact anatomical knowledge of this region can have important advantages during surgery, since some pathology can invade inside cavities or tunnels otherwise not seen by instrumentation that produces a straight-line view (e.g. microscope).

The VAGUS insight into psychosis scale--self-report and clinician-rated versions.

The aim of this study was to develop self-report and clinician-rated versions of an insight scale that would be easy to administer, sensitive to small changes, and inclusive of the core dimensions of clinical insight into psychosis. Ten-item self-report (VAGUS-SR) and five-item clinician-rated (VAGUS-CR) scales were designed to measure the dimensions of insight into psychosis and evaluated in 215 and 140 participants, respectively (www.vagusonline.com). Tests of reliability and validity were performed. Both the VAGUS-SR and VAGUS-CR showed good internal consistency and reliability. They demonstrated good convergent and discriminant validity. Both versions were strongly correlated with one another and with the Schedule for the Assessment of Insight and Birchwood Insight Scale. Exploratory factor analyses identified three possible latent components of insight. The VAGUS-CR and VAGUS-SR are valid, reliable and easy to administer. They are build on previous insight scales with separate clinician-rated and self-report versions. The VAGUS-SR exhibited a multidimensional factor structure. Using a 10-point Likert scale for each item, the VAGUS has the capacity to detect small, temporally sensitive changes in insight, which is essential for intervention studies with neurostimulation or rapidly acting medications.

The behavior of mastoidectomy cavities following modified radical mastoidectomy.

OBJECTIVES/HYPOTHESIS: An analysis of the frequency and intensity of postoperative aftercare required for modified radical mastoidectomy (MRM) and patterns of healing in the postoperative period. STUDY DESIGN: A retrospective review of all primary modified radical mastoidectomies carried out for cholesteatoma under the care of the senior author between the years of 2004 and 2009 with minimum follow-up of 2 years. METHODS: The time and number of interventions required to achieve a stable and dry mastoid cavity were collected. Cross-sectional and longitudinal analysis of the behavior of the cavities was carried out. RESULTS: Overall, 73 cases (71 patients) were identified. Patients were followed up for a median of 45.7 months (interquartile range, 31.8-70.5). After initial debridement, most cavities settled rapidly, but this was not always predictable, with a large proportion requiring further clinical intervention after the cavity was stable, sometimes for prolonged periods of time. At the time of analysis, 73% had achieved a stable cavity, 17 (23%) still required attention (nine for wax removal and eight for debridement); two were lost to follow-up. No revision surgeries were required. At 6 months, 36% of cavities were settled, 42% at 1 year, 53% at 18 months, and 62% at 2 years. After two standard postoperative visits, a total of 632 visits were made by these patients. CONCLUSIONS: Following MRM, the majority of patients achieve a dry, self-cleaning mastoid cavity. This might require periods of intense care interspersed with periods of quiescence. These results allow the benefits of this procedure to be put in the context of the entire patient journey.

Intraoperative cone-beam computed tomography and multi-slice computed tomography in temporal bone imaging for surgical treatment.

OBJECTIVE: Conventional computed tomography (CT) imaging is the standard imaging technique for temporal bone diseases, whereas cone-beam CT (CBCT) imaging is a very fast imaging tool with a significant less radiation dose compared with conventional CT. We hypothesize that a system for intraoperative cone-beam CT provides comparable image quality to diagnostic CT for identifying temporal bone anatomical landmarks in cadaveric specimens. STUDY DESIGN: Cross-sectional study. SETTING: University tertiary care facility. SUBJECTS AND METHODS: Twenty cadaveric temporal bones were affixed into a head phantom and scanned with both a prototype cone-beam CT C-arm and multislice helical CT. Imaging performance was evaluated by 3 otologic surgeons and 1 head and neck radiologist. Participants were presented images in a randomized order and completed landmark identification questionnaires covering 21 structures. RESULTS: CBCT and multislice CT have comparable performance in identifying temporal structures. Three otologic surgeons indicated that CBCT provided statistically equivalent performance for 19 of 21 landmarks, with CBCT superior to CT for the chorda tympani and inferior for the crura of the stapes. Subgroup analysis showed that CBCT performed superiorly for temporal bone structures compared with CT. The radiologist rated CBCT and CT as statistically equivalent for 18 of 21 landmarks, with CT superior to CBCT for the crura of stapes, chorda tympani, and sigmoid sinus. CONCLUSION: CBCT provides comparable image quality to conventional CT for temporal bone anatomical sites in cadaveric specimens. Clinical applications of low-dose CBCT imaging in surgical planning, intraoperative guidance, and postoperative assessment are promising but require further investigation.

Evaluation of intraoperative cone beam computed tomography and optical drill tracking in temporal bone surgery.

OBJECTIVES/HYPOTHESIS: A prototype system for intraoperative cone beam computed tomography (CBCT) imaging has been developed and augmented with real time optical tracking of a surgical drill. We hypothesize that this system provides sufficient accuracy for guidance of temporal bone surgery. STUDY DESIGN: Basic research. METHODS: Measurements of drill localization accuracy using CBCT imaging were obtained with a custom three-dimensional calibration object. Integrated CBCT imaging and drill tracking were prospectively evaluated on 12 cadaver temporal bones. Six inexperienced and six experienced surgeons conducted four surgical tasks: cortical mastoidectomy, posterior tympanotomy, cochleostomy, and a translabyrinthine approach to the internal auditory canal. Questionnaires provided expert feedback on tracking accuracy and system usability. RESULTS: Target registration error measurements of drill tracking accuracy and precision yielded a mean of 0.76 mm, a maximum of 1.30 mm, and a standard deviation of 0.21 mm. Anatomical landmark identification tasks (e.g., facial nerve, incus, semicircular canals, cochlea) provided additional validation of system accuracy. The usability and utility of the guidance system were positively rated by both groups of surgeons, with further modifications underway to improve tracking line of sight and registration workflow. Experienced but in particular inexperienced surgeons indicated significant benefits in cases involving extensive disease, abnormal anatomy, and loss of anatomical landmarks. CONCLUSIONS: The integration of intraoperative CBCT imaging with optical tracking provides sufficient accuracy to localize anatomical structures within the temporal bone using an otological drill. Future studies will explore the role of this technology in complex oncological resections, in surgery for congenital anomalies, and as a tool for teaching.

Transcanal endoscopic management of cholesteatoma.

A detailed and comprehensive discussion of transcanal endoscopic management of cholesteatoma is presented. After a presentation of the anatomy of the area, the rationale, advantages and limitations, technique, and long-term results of each technique are presented. A case presentation follows each technique. Techniques presented are: endoscopic transcanal management of limited cholesteatoma, endoscopic open cavity management of cholesteatoma, and expanded transcanal access to middle ear and petrous apex.

Endoscopic management of chronic otitis media and tympanoplasty.

The endoscope allows for better inspection for cholesteatoma in cases with chronic otitis media, better access to selective epitympanic poor ventilation and secondary selective chronic otitis media, better visualization of anterior poor ventilation of the mesotympanum (reestablishing adequate ventilation to the mesotympanum), better visualization and reconstruction of anterior tympanic membrane perforations, allows use of Sheehy's lateral graft tympanoplasty through a transcanal approach, and increases the odds of preoperative detection of ossicular chain disruption associated with perforations.