Printing in Time for Cranio-Maxillo-Facial Trauma Surgery: Key Parameters to Factor in.

Study Design: retrospective cohort study. Objective: 3D printing is used extensively in cranio-maxillo-facial (CMF) surgery, but difficulties remain for surgeons to implement it in an acute trauma setting because critical information is often omitted from reports. Therefore, we developed an in-house printing pipeline for a variety of cranio-maxillo-facial fractures and characterized each step required to print a model in time for surgery. Methods: All consecutive patients requiring in-house 3D printed models in a level 1 trauma center for acute trauma surgery between March and November 2019 were identified and analyzed. Results: Sixteen patients requiring the printing of 25 in-house models were identified. Virtual Surgical Planning time ranged from 0h 08min to 4h 41min (mean = 1h 46min). The overall printing phase per model (pre-processing, printing, and post-processing) ranged from 2h 54min to 27h 24min (mean = 9h 19min). The overall success rate of prints was 84%. Filament cost was between $0.20 and $5.00 per model (mean = $1.56). Conclusions: This study demonstrates that in-house 3D printing can be done reliably in a relatively short period of time, therefore allowing 3D printing usage for acute facial fracture treatment. When compared to outsourcing, in-house printing shortens the process by avoiding shipping delays and by having a better control over the printing process. For time-critical prints, other time-consuming steps need to be considered, such as virtual planning, pre-processing of 3D files, post-processing of prints, and print failure rate.

In-house 3D Model Printing for Acute Cranio-maxillo-facial Trauma Surgery: Process, Time, and Costs.

Three-dimensional (3D) printing is used extensively in cranio-maxillo-facial (CMF) surgery, but its usage is limited in the setting of acute trauma specifically, as delays in outsourcing are too great. Therefore, we developed an in-house printing solution. The purpose of this study was to describe this process for surgeons treating acute CMF trauma. This series describes the printing process, time required, and printing material costs involved for in-house printing applied to a variety of acute CMF trauma cases involving the upper, middle, and lower thirds of the face and skull. All consecutive patients requiring in-house 3D printed models in a level 1 trauma center for acute trauma surgery in mid-2019 were identified and analyzed. Nine patients requiring the printing of 12 in-house models were identified. The overall printing time per model ranged from 2 hours, 36 minutes to 26 hours, 54 minutes (mean = 7h 55 min). Filament cost was between $0.20 and $2.65 per model (mean = $0.95). This study demonstrates that in-house 3D printing can be done in a relatively short period of time, therefore allowing 3D printing usage for various acute facial fracture treatments. The rapid improvements in the usability of 3D software and printing technology will likely contribute to further adoption of these technologies by CMF-trauma surgeons.

Speech Perception Changes in the Acoustically Aided, Nonimplanted Ear after Cochlear Implantation: A Multicenter Study.

In recent years there has been an increasing percentage of cochlear implant (CI) users who have usable residual hearing in the contralateral, nonimplanted ear, typically aided by acoustic amplification. This raises the issue of the extent to which the signal presented through the cochlear implant may influence how listeners process information in the acoustically stimulated ear. This multicenter retrospective study examined pre- to postoperative changes in speech perception in the nonimplanted ear, the implanted ear, and both together. Results in the latter two conditions showed the expected increases, but speech perception in the nonimplanted ear showed a modest yet meaningful decrease that could not be completely explained by changes in unaided thresholds, hearing aid malfunction, or several other demographic variables. Decreases in speech perception in the nonimplanted ear were more likely in individuals who had better levels of speech perception in the implanted ear, and in those who had better speech perception in the implanted than in the nonimplanted ear. This raises the possibility that, in some cases, bimodal listeners may rely on the higher quality signal provided by the implant and may disregard or even neglect the input provided by the nonimplanted ear.

Contemporary Speech and Oral Language Care for Deaf and Hard-of-Hearing Children Using Hearing Devices.

Contemporary speech and language interventions are not limited to disabilities but embrace the pragmatics of communication behaviors from the perspective of functional social participation. Accordingly, current speech and language therapies for deaf and hard-of-hearing children include a broad spectrum of approaches and techniques. This paper explores contemporary approaches and techniques for speech and oral language interventions for deaf and hard-of-hearing children using hearing devices, evidence of efficacy and how they are implemented in diverse clinical practices.

Effectiveness of Rehabilitation Approaches Proposed to Children With Severe-to-Profound Prelinguistic Deafness on the Development of Auditory, Speech, and Language Skills: A Systematic Review.

Purpose The purpose of this systematic review is to identify and evaluate the available scientific evidence on the effectiveness of rehabilitation approaches proposed to children with severe-to-profound prelinguistic deafness on the hearing, speech, and language skills development. Method Databases (PubMed, CINHAL, PsycInfo, Cochrane, ERIC, and EMBASE) were searched with relevant key words (children, deafness, rehabilitation approach, auditory, speech, and language). Studies published between 2000 and 2017 were included. The methodological quality of the studies was evaluated with the Quality Assessment Tool for Quantitative Studies, and the level of evidence was evaluated with the Oxford Centre for Evidence-Based Medicine Levels of Evidence. Every step of the selection and analysis was made by 2 independent judges. Results Of 1,739 articles listed in different databases, 38 met the inclusion criteria and were selected for analysis. The majority of included articles present a relatively low level of evidence. Rehabilitation approaches that do not include signs appear more frequently associated with a better auditory, speech, and language development, except for receptive language, than approaches that included any form of signs. Conclusion More robust studies are needed to decide on the approach to prioritize with severe-to-profound deaf children.

Intraoperative Surgical Navigation Reduces the Surgical Time Required to Treat Acute Major Facial Fractures.

BACKGROUND: Assessing bone reduction and implant placement in facial fractures is time-consuming because of limited visibility. An intraoperative navigation system allows real-time confirmation of bone positioning and implant placement on the patient's computed tomographic scan. This circumvents the visibility problem and therefore appears to shorten the surgery time. The goal of this study was therefore to determine whether intraoperative navigation reduces the surgical time required to treat patients with acute major facial fractures. METHODS: In this retrospective quasi-experimental study, 50 patients with major facial fractures were identified and randomly assigned to treatment groups. Twenty-two were treated without the use of a navigation system, and 28 were treated using navigation. The Facial frActure Severity Score (FASS) was devised to better assess and control for complexity of cases and control for possible selection bias. RESULTS: The FASS was directly linked to surgery time, whether or not navigation was used. An analysis of covariance demonstrated that the surgical time required to treat major facial fractures, taking into account the FASS, was reduced by 36.1 percent (124.8 minutes) when navigation was used. CONCLUSIONS: This study compared the surgical time required to treat patients with major facial fractures, with and without a navigation system. The use of a navigation system reduced the surgical time by 36.1 percent. This is a significant improvement in reducing the length of craniomaxillofacial procedures. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Development and validation of the FrBio, an international French adaptation of the AzBio sentence lists.

Objectives: The goal of this work was to develop and normalise an international French version of the AzBio sentence test. Design: A corpus of 1000 sentences was generated. These sentences were recorded with four talkers and processed through a four-channel cochlear implant simulation. The mean intelligibility for each sentence achieved by 16 normal-hearing listeners was computed. The consecutively ordered 165 sentences from each talker rendering an average score of 85% were sequentially assigned to 33 lists of 20 sentences. All lists were presented to 30 normal-hearing and 25 hearing-impaired listeners in order to verify their equivalency. Thirty normal-hearing adults were also recruited to assess the test's psychometrics and define norms. Results: The results of the list equivalency validation study showed no significant differences in percent correct scores for 30 sentence lists. A binomial distribution model was used to estimate the 95% critical differences for each potential percentage score. Normalization data showed an average performance between 96% and 99% with a very low standard deviation. Conclusions: With a set of 30 lists, researchers and clinicians can use the FrBio to evaluate a large number of experimental conditions; changes in performance over time or across conditions can then be tracked.

Golden ratio and phyllotaxis, a clear mathematical link.

Exploiting Markoff's theory for rational approximations of real numbers, we explicitly link how hard it is to approximate a given number to an idealized notion of growth capacity for plants which we express as a modular invariant function depending on this number. Assuming that our growth capacity is biologically relevant, this allows us to explain in a satisfying mathematical way why the golden ratio occurs in nature.

Early CT changes in patients admitted for thrombectomy: Intrarater and interrater agreement.

OBJECTIVE: To systematically review the literature and assess agreement on the Alberta Stroke Program Early CT Score (ASPECTS) among clinicians involved in the management of thrombectomy candidates. METHODS: Studies assessing agreement using ASPECTS published from 2000 to 2015 were reviewed. Fifteen raters reviewed and scored the anonymized CT scans of 30 patients recruited in a local thrombectomy trial during 2 independent sessions, in order to study intrarater and interrater agreement. Agreement was measured using intraclass correlation coefficients (ICCs) and Fleiss kappa statistics for ASPECTS and dichotomized ASPECTS at various cutoff values. RESULTS: The review yielded 30 articles reporting 40 measures of agreement. Populations, methods, analyses, and results were heterogeneous (slight to excellent agreement), precluding a meta-analysis. When analyzed as a categorical variable, intrarater agreement was slight to moderate (κ = 0.042-0.469); it reached a substantial level (κ > 0.6) in 11/15 raters when the score was dichotomized (0-5 vs 6-10). The interrater ICCs varied between 0.672 and 0.811, but agreement was slight to moderate (κ = 0.129-0.315). Even in the best of cases, when ASPECTS was dichotomized as 0-5 vs 6-10, interrater agreement did not reach a substantial level (κ = 0.561), which translates into at least 5 of 15 raters not giving the same dichotomized verdict in 15% of patients. CONCLUSIONS: In patients considered for thrombectomy, there may be insufficient agreement between clinicians for ASPECTS to be reliably used as a criterion for treatment decisions.

A Retrospective Multicenter Study Comparing Speech Perception Outcomes for Bilateral Implantation and Bimodal Rehabilitation.

OBJECTIVES: To compare speech perception outcomes between bilateral implantation (cochlear implants [CIs]) and bimodal rehabilitation (one CI on one side plus one hearing aid [HA] on the other side) and to explore the clinical factors that may cause asymmetric performances in speech intelligibility between the two ears in case of bilateral implantation. DESIGN: Retrospective data from 2247 patients implanted since 2003 in 15 international centers were collected. Intelligibility scores, measured in quiet and in noise, were converted into percentile ranks to remove differences between centers. The influence of the listening mode among three independent groups, one CI alone (n = 1572), bimodal listening (CI/HA, n = 589), and bilateral CIs (CI/CI, n = 86), was compared in an analysis taking into account the influence of other factors such as duration of profound hearing loss, age, etiology, and duration of CI experience. No within-subject comparison (i.e., monitoring outcome modifications in CI/HA subjects becoming CI/CI) was possible from this dataset. Further analyses were conducted on the CI/CI subgroup to investigate a number of factors, such as implantation side, duration of hearing loss, amount of residual hearing, and use of HAs that may explain asymmetric performances of this subgroup. RESULTS: Intelligibility ranked scores in quiet and in noise were significantly greater with both CI/CI and CI/HA than with a CI-alone group, and improvement with CI/CI (+11% and +16% in quiet and in noise, respectively) was significantly better than with CI/HA (+6% and +9% in quiet and in noise, respectively). From the CI/HA group, only subjects with ranked preoperative aided speech scores >60% performed as well as CI/CI participants. Furthermore, CI/CI subjects displayed significantly lower preoperative aided speech scores on average compared with that displayed by CI/HA subjects. Routine clinical data available from the present database did not explain the asymmetrical results of bilateral implantation. CONCLUSIONS: This retrospective study, based on basic speech audiometry (no lateralization cues), indicates that, on average, a second CI is likely to provide slightly better postoperative speech outcome than an additional HA for people with very low preoperative performance. These results may be taken into consideration to refine surgical indications for CIs.

Comparison of eSRTs and comfort levels in users of Digisonic SP cochlear implants.

OBJECTIVE: This project proposes to assess the relation between the electrical stapedius reflex threshold (eSRT) and comfort levels in users of the Digisonic SP cochlear implant. METHODS: Cross-sectional study, where eSRTs are compared to the comfort current levels at 2 weeks and at 1-year post-fitting in a group of 11 adults getting a significant improvement in open set speech recognition from a Digisonic SP cochlear implant. RESULTS: The linear relation between eSRTs and comfort levels results in Pearson correlation coefficients of 0.65 (P < 0.01; at 2 weeks) to 0.60 (P < 0.05; at 1 year). The comfort levels can be predicted from the eSRTs for the Digisonic SP device from the model equation C level = 19.12 + 0.41*eSRT within a clinically acceptable margin of error. DISCUSSION: Reflex thresholds could be obtained in most participants, and in most channels of the Digisonic implant. The equation model appears as a quite reliable predictor of comfort levels for users of this device.

Photonic bandgap Bragg fiber sensors for bending/displacement detection.

We demonstrate an amplitude-based bending/displacement sensor that uses a plastic photonic bandgap Bragg fiber with one end coated with a silver layer. The reflection intensity of the Bragg fiber is characterized in response to different displacements (or bending curvatures). We note that the Bragg reflector of the fiber acts as an efficient mode stripper for the wavelengths near the edge of the fiber bandgap, which makes the sensor extremely sensitive to bending or displacements at these wavelengths. Besides, by comparison of the Bragg fiber sensor to a sensor based on a standard multimode fiber with similar outer diameter and length, we find that the Bragg fiber sensor is more sensitive to bending due to the presence of a mode stripper in the form of a multilayer reflector. Experimental results show that the minimum detection limit of the Bragg fiber sensor can be as small as 3 µm for displacement sensing.

Factors affecting auditory performance of postlinguistically deaf adults using cochlear implants: an update with 2251 patients.

OBJECTIVE: To update a 15-year-old study of 800 postlinguistically deaf adult patients showing how duration of severe to profound hearing loss, age at cochlear implantation (CI), age at onset of severe to profound hearing loss, etiology and CI experience affected CI outcome. STUDY DESIGN: Retrospective multicenter study. METHODS: Data from 2251 adult patients implanted since 2003 in 15 international centers were collected and speech scores in quiet were converted to percentile ranks to remove differences between centers. RESULTS: The negative effect of long duration of severe to profound hearing loss was less important in the new data than in 1996; the effects of age at CI and age at onset of severe to profound hearing loss were delayed until older ages; etiology had a smaller effect, and the effect of CI experience was greater with a steeper learning curve. Patients with longer durations of severe to profound hearing loss were less likely to improve with CI experience than patients with shorter duration of severe to profound hearing loss. CONCLUSIONS: The factors that were relevant in 1996 were still relevant in 2011, although their relative importance had changed. Relaxed patient selection criteria, improved clinical management of hearing loss, modifications of surgical practice, and improved devices may explain the differences.

Pre-, per- and postoperative factors affecting performance of postlinguistically deaf adults using cochlear implants: a new conceptual model over time.

OBJECTIVE: To test the influence of multiple factors on cochlear implant (CI) speech performance in quiet and in noise for postlinguistically deaf adults, and to design a model of predicted auditory performance with a CI as a function of the significant factors. STUDY DESIGN: Retrospective multi-centre study. METHODS: Data from 2251 patients implanted since 2003 in 15 international centres were collected. Speech scores in quiet and in noise were converted into percentile ranks to remove differences between centres. The influence of 15 pre-, per- and postoperative factors, such as the duration of moderate hearing loss (mHL), the surgical approach (cochleostomy or round window approach), the angle of insertion, the percentage of active electrodes, and the brand of device were tested. The usual factors, duration of profound HL (pHL), age, etiology, duration of CI experience, that are already known to have an influence, were included in the statistical analyses. RESULTS: The significant factors were: the pure tone average threshold of the better ear, the brand of device, the percentage of active electrodes, the use of hearing aids (HAs) during the period of pHL, and the duration of mHL. CONCLUSIONS: A new model was designed showing a decrease of performance that started during the period of mHL, and became faster during the period of pHL. The use of bilateral HAs slowed down the related central reorganization that is the likely cause of the decreased performance.

Message transmission efficiency through five telecommunication technologies for signing deaf users.

This cross-sectional research design compares the efficiency of videoconferencing in distance communication for signing deaf persons with that of teletypewriter (TTY)-based telecommunication for the deaf. The efficiency of message transmission was evaluated among 30 signing deaf persons (18 to 65 years) under the six following experimental conditions: (a) Omnitor Allan eC software, (b) Polycom ViaVideo II software, (c) Microsoft Windows Live Messenger software, (d) the D-Link videophone, (e) TTY (written French), and (f) face to face (reference standard). Three timed intelligibility tests and a satisfaction assessment were carried out for each of the experimental conditions. Results showed that videoconferencing technologies offer a better efficacy/time ratio for communication than does TTY. Communication using videoconferencing technologies was very similar to face-to-face communication; this was also true for technologies that are not designed specifically for the deaf population. Equivalent satisfaction levels were observed between TTY and videoconferencing technologies. Microsoft Windows Live Messenger was less preferred due to image fluidity issues.

HO* radicals induce an unexpected high proportion of tandem base lesions refractory to repair by DNA glycosylases.

Reaction of HO(*) radicals with double-stranded calf thymus DNA produces high levels of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) and, to a minor extent, 8-oxo-7,8-dihydro-2'-deoxyadenosine (8-oxodAdo). Formation of the hydroxylated purine lesions is explained by addition of HO(*) to the C8 position of the purine moiety. It has been reported that tandem lesions containing a formylamine residue neighboring 8-oxodGuo could be produced through addition of a transiently generated pyrimidine peroxyl radical onto the C8 of an adjacent purine base. Formation of such tandem lesions accounted for approximately 10% of the total 8-oxodGuo. In the present work we show that addition of HO(*) onto the C8 of purine accounts for only approximately 5% of the generated 8-oxodGuo. About 50% of the 8-hydroxylated purine lesions, including 8-oxodGuo and 8-oxodAdo, are involved in tandem damage and are produced by peroxyl addition onto the C8 of a vicinal purine base. In addition, the remaining 45% of the 8-oxodGuo are produced by an electron transfer reaction, providing an explanation for the higher yield of formation of 8-oxodGuo compared to 8-oxodAdo. Interestingly, we show that >40% of the 8-oxodGuo involved in tandem lesions is refractory to excision by DNA glycosylases. Altogether our results demonstrate that, subsequently to a single oxidation event, peroxidation reactions significantly increase the yield of formation of hydroxylated purine modifications, generating a high proportion of tandem lesions partly refractory to base excision repair.

Cochlear implantation in postmeningitic deafness.

OBJECTIVES/HYPOTHESIS: To propose guidelines in the management of a profound bilateral sensorineural hearing loss after bacterial meningitis. STUDY DESIGN: Retrospective chart review. PATIENTS: All 40 postmeningitic cochlear implantation surgeries performed between August 1987 and April 2007. METHODS: Descriptive analysis of data on the cause of meningitis, preoperative imaging evaluation, age at implantation, time elapsed between meningitis and implantation, and relevant surgical findings. RESULTS: Twenty-seven children and 13 adults with postmeningitic deafness were implanted. Mean age was 3 years 8 months for the children and 44 years and 10 months for the adults. The mean time delay between meningitis and surgery was 2 years 1 month for children and 28 years for adults. Eighteen children (67%) were implanted within a year. Labyrinthitis ossificans was evidenced at surgery in 62% of patients. Intraoperative cochlear ossification was classified according to the scale described by Smullen and Balkany (2005). Stage II ossification was seen in 3 patients within 49 days, with 1 of them as soon as 21 days. There was a partial insertion in 9 patients secondary to ossification. Open-set speech discrimination was achieved by 37% of the children (10 of 27) and 23% of the adults (3 of 13). CONCLUSION: We recommend early cochlear implantation for patients with bilateral profound deafness secondary to meningitis.