Simultaneous supervision by microscope of endoscope-assisted microsurgery via presigmoid retrolabyrinthine approach: A pilot study

OBJECTIVE

To examine the impact of integrated hybrid operating rooms for endoscope-assisted microsurgery using the presigmoid retrolabyrinthine (RL) approach, and to determine the value of simultaneous supervision of skull base endoscopic procedures by microscope.

MATERIAL AND METHODS

We retrospectively reviewed endoscope-assisted surgery using the RL approach at our institution between September 2013 and January 2017. The simultaneous supervision of endoscopic procedures by microscope was realized using the integrated hybrid system. Intra- or postoperative complications and surgical outcomes were analyzed. All patients were followed for at least 1 year.

RESULTS

In total, 32 patients were studied: 4 vestibular schwannomas, 5 cholesteatomas, 8 hemifacial spasms, 5 glossopharyngeal neuralgias, and 10 Ménière's disease. In patients with vestibular schwannoma or cholesteatoma, complete removal was performed in all patients. In patients with Ménière's disease, hemifacial spasm or glossopharyngeal neuralgia, satisfactory symptom relief was achieved in all patients. Two (6.3%) patients had hearing loss after surgery which did not recover. One (3.1%) patient with vestibular schwannoma had mild facial palsy (HB III) at 2 weeks after the operation and recovered to near normal facial nerve function (HB II) at 1 year after surgery. No permanent or transient dysfunction of the trigeminal nerve or the lower cranial nerves was observed during follow-up. No complications such as cerebrospinal fluid (CSF) leakage or meningitis were observed.

CONCLUSION

The endoscope provided a clearer and larger view, which solved the limitations of surgery using the RL approach. Endoscopic surgery under simultaneous supervision by microscope was safe and efficient in hearing preservation as well as in preservation of facial nerve function. An integrated operation room provided better support and the ability to switch quickly between these various complex devices.

A statistical tool for risk assessment as a function of the number of lymph nodes retrieved from rectal cancer patients

AIM

Although a minimum of 12 lymph nodes (LNs) has been recommended for examination in colorectal cancer patients there remains considerable debate with regard to rectal cancer. Inadequacy of examined LNs could lead to understaging and inappropriate treatment as a consequence. We describe a statistical tool that allows an estimate of the probability of false-negative nodes.

METHOD

A total of 26 778 patients diagnosed between 2004 and 2013 with rectal adenocarcinoma [tumour stage (T stage) 1-3] who did not receive neoadjuvant therapies and had at least one histologically assessed LN were extracted from the Surveillance, Epidemiology and End Results (SEER) database. A statistical tool using beta-binomial distribution was developed to estimate the probability of missing a positive node as a function of the total number of LNs examined and T stage.

RESULTS

The probability of falsely identifying a patient as node-negative decreased with increasing number of nodes examined for each stage. It was estimated to be 72%, 66% and 52% for T1, T2 and T3 patients, respectively, with a single node examined. To confirm an occult nodal disease with 90% confidence, 5, 9 and 29 nodes need to be examined for patients from stages T1, T2 and T3, respectively.

CONCLUSION

The false-negative rate of the examined LNs in rectal cancer was verified to be dependent preoperatively on the clinical T stage. A more accurate nodal staging score was developed to recommend a threshold for the minimum number of examined nodes with regard to the favoured level of confidence.

Opposite Aerosol Index-Cloud Droplet Effective Radius Correlations Over Major Industrial Regions and Their Adjacent Oceans

The Moderate Resolution Imaging Spectroradiometer (MODIS) C6 L3 and the European Centre for Medium-Range Weather Forecasts (ECMWF) ERA-Interim reanalysis data from 2003 to 2016 are employed to study aerosol-cloud correlations over three industrial regions and their adjacent oceans, as well as explore the impact of meteorological conditions on the correlations. The analysis focusing on liquid and single-layer clouds indicates an opposite aerosol-cloud correlation between land and ocean; namely, cloud effective radius is positively correlated with aerosol index over industrial regions (positive slopes), but negatively correlated over their adjacent oceans (negative slopes), for a quasi-constant liquid water path. The positive slopes are relatively large under low lower-tropospheric stability (LTS; weakly stable condition), but much weaker or even become negative under high LTS (stable conditions) and high liquid water path. The occurrence frequency of cloud top height (CTH) and LTS suggests that positive correlations are more likely corresponding to relatively high CTH and low LTS, while negative to low CTH and high LTS.

Intraoperative Conebeam CT for Assessment of Intracochlear Positioning of Electrode Arrays in Adult Recipients of Cochlear Implants

BACKGROUND AND PURPOSE

Intraoperative conebeam CT has been introduced into the operating room and provides quick radiologic feedback. This study aimed to investigate its utility in the assessment of the positioning of the electrode array after cochlear implantation.

MATERIALS AND METHODS

This was a retrospective study of 51 patients (65 ears) with intraoperative imaging by conebeam CT (O-arm) after cochlear implantation between 2013 and 2017. Correct placement into the cochlea was immediately identified. Positioning assessments were later analyzed with OsiriX software.

RESULTS

Intraoperative imaging was quickly performed in all cases. No misplacement into the vestibule or semicircular canals was found. A foldover of the implanted array was identified in 1 patient. Secondary analysis by 2 raters showed excellent agreement on insertion depth angle (intraclass correlation = 0.96, P < .001) and length of insertion of the electrode array (intraclass correlation coefficient = 0.93, P = .04) measurements. The evaluation of the number of extracochlear electrodes was identical between the 2 raters in 78% of cases (Cohen κ = 0.55, P < .001). The scalar position was inconsistent between raters. When we compared O-arm and high-resolution CT images in 14 cases, the agreement was excellent for insertion depth angle (intraclass correlation coefficient = 0.97, P < .001) and insertion length (intraclass correlation coefficient = 0.98, P < .001), good for the number of extracochlear electrodes (Cohen κ = 0.63, P = .01), but moderate for the scalar position (Cohen κ = 0.59, P = .02).

CONCLUSIONS

Intraoperative conebeam CT using the O-arm is a safe, rapid, easy, and reliable procedure to immediately identify a misplacement or foldover of an electrode array. The insertion depth angle, insertion length, and number of electrodes inserted can be accurately assessed.

International consensus (ICON) on management of otitis media with effusion in children

Otitis media with effusion (OME) is a common childhood disease defined as the presence of liquid in the middle ear without signs or symptoms of acute ear infection. Children can be impacted mainly with hearing impairment and/or co-occurring recurrent acute otitis media (AOM) thus requiring treatment. Although many meta-analyses and national guidelines have been issued, management remains difficult to standardize, and use of surgical and medical treatments continue to vary. We convened an international consensus conference as part of the 2017 International Federation of Oto-rhino-laryngological Societies Congress, to identify best practices in OME management. Overall, regional differences were minor and consensual management was obtained on several important issues. At initial assessment, although a thorough medical examination is necessary to seek reflux, allergy or nasal obstruction symptoms; an age-appropriate auditory test is the only assessment required in children without abnormal history. Non-surgical treatments poorly address the underlying problem of an age-dependent dysfunctional Eustachian tube; auto-inflation seems to be the only beneficial, low-risk and low-cost non-surgical therapy. There was a clear international recommendation against using steroids, antibiotics, decongestants or antihistamines to treat OME, because of side-effects, cost issues and no convincing evidence of long-term effectiveness. Decisions to insert tympanostomy ventilation tubes should be based on an auditory test but also take into account the child's context and overall hearing difficulties. Tubes significantly improve hearing and reduce the number of recurrent AOM with effusion while in place. Adjuvant adenoidectomy should be considered in children over four years of age, and in those with significant nasal obstruction or infection.

[Analysis of the effect of mesial implant position on surrounding bone stress of mandibular edentulous jaw under dynamic loads]

Objective: To evaluate the effect of different placement of mesial implants in edentulous jaws on the stress of the implant and the surrounding bone tissue by three-dimensional (3D)finite element analysis. Methods: Cone-beam CT data of mandibular edentulous patients was transferred into Mimics 17.0 and UG NX8.5 software, and three groups of 3D solid model were established: two mesial implants were implanted in the anterior region of the mandible (bilateral central incisor, lateral incisor, canine), and two distal oblique implant with 30° were implanted in the mandibular second premolar area(5 mm near the mental foramen). Set mandible 3D model with 4 implant by using UG NX8.5 software, produced 3 groups (mandible Ⅰ-Ⅲ). We took dynamic loading on models with help of software Abaqus 6.12, working side posterior teeth loading was set to 150 N and the simulation cycle was 0.875 s. The first stage: 0.000 s to 0.130 s, the lower jaw moves outward (moving toward the side of the work), with no contact between the upper and lower teeth; the second stage: 0.130 s to 0.150 s, mandibular upward, the same tooth tip of the working side were relative, the loading position were the posterior buccal tip, tongue tip; the third stage: 0.150 s to 0.260 s, the buccal slopes of buccal tips of mandibular posterior teeth glide along the lingual slopes of buccal tips of maxillary posterior teeth, the loading force was from the buccal side to the lingual side, the long axis of the tooth was 45°, loaded on the buccal slopes of buccal tips of posterior teeth; the fourth stage: 0.260 s to 0.300 s, the lingual slopes of buccal tips of mandibular posterior teeth glide along the buccal slopes of the tongue tips of maxillary posterior teeth, separate from the tip of the tooth at half the length, the loading force was from the lingual side to the buccal side, the long axis of the tooth was 45°, loaded on the lingual slopes of buccal tips of posterior teeth; the fifth stage: 0.300 s to 0.875 s, at the unloading stage, mandibular posterior teeth were separated from the maxillary teeth and returned to the intercuspal position. The loading position varied according to the mastication cycle. The stress distribution of implant and surrounding bone tissue at different stages of each model were observed. Results: From the early stage to chew occlusal contact to the end of the mastication cycle, three groups of models were displayed: the stress of distal implants was greater than that of mesial implants and the neck stress reached the maximum and gradually decreased to the root tip. The stress of distal implant bone was greater than that of mesial implant bone and the stress of distal bone of distal implant was greater than that of mesial bone of distal implant. All the stress peak showed a gradual increase, and the stress reach the maximum at the fourth stage. In the 3 models, the bone stress around the distal implant of model of the anterior implant located in the lateral incisor region was the lowest. The peak stress of cortical bone of the distal position of implant was 58.7 MPa. The bone stress around the distal implant of model of the anterior implant located in the canine region reached the maximum, and the peak stress of cortical bone of the distal position of implant was 135.6 MPa. Conclusions: When mesial implants of edentulous jaws located in the lateral incisor region, it is good for stress dispersion.

[A combination use of endoscope and microscope in cerebral pontine angle surgery]

Objective: To evaluate the application of combination use of microscope and endoscope in cerebral pontine angle (CPA) surgery. Methods: A total of 72 patients undergone lateral skull base surgeries via endoscope under microscopic control from January 2006 to January 2015 was reviewed respectively. The patients including 35 males and 37 females were composed of 22 cases of vestibular swannnomas, 45 cases of cranial neuropathy and 5 cases of CPA chelesteatoma. Twenty cases of vestibular swannnomas, 15 cases of cranial neuropathy and 2 cases of CPA chelesteatoma undergone the surgery via retrosigmoid approach, while other cases undergone the surgery via retrolabyrinthine approach. Surgical procedures were accomplished under the control of microscope and different angular endoscope with imaging fusion. The surgical results were evaluated according to subjective and objective criteria, and all patients were followed up for 15 years. Results: The symptoms was disappeared in the cranial neuropathy patients, without facial paralysis, complication of other nerves or hearing loss. Twenty-two patients with vestibular schwannomas got total tumor removal without facial palsy or neurological deficits; useful hearing was preserved in 16 of 22 patients (72.7%), and no tumor recurrence was found during 1-5 years follow-up. There was also no facial palsy or other complications in 5 cases of CPA chelesteatoma, which gained completely surgical removal; useful hearing was preserved in 3 of 5 cases of these patients and no recurrence was occurred during 1-1.5 years follow-up. Conclusions: A combination use of endoscope and microscope could combine advantages and avoid disadvantages of two techniques. It can provide better exposure with minimal invasion in CPA surgery, and is especially applicable in surgery for cranial neuropathy, vestibular schwannoma and CPA cholesteatoma, which should be performed through retrosigmoid approach and retrolabyrinthine approach.

[Relationship and influencing factors between the amplitude change of supramaximal facial nerve stimulation during acoustic neuroma removal and facial function outcome]

OBJECTIVE

To investigate the relationship between the amplitude change of supramaximal facial nerve stimulation during acoustic neuroma removal and facial function outcome, and discuss its influencing factors.

METHODS

Retrospective study of 34 acoustic neuroma patients. Intraoperative amplitude by supramaximal stimulation, facial function outcome, tumor size, surgical approach, facial nerve course pattern, and tumor cystic status, as well as tumor adhesion degree were collected and analyzed by SPSS 17.0.

RESULTS

Acoustic neurnomas were removed in all 34 patients without intra- and postoperative complications, the facial nerve were all anatomically preserved. Two weeks later, 5 cases showed facial function HB Grade Ⅰ, 13 HB Ⅱ, 11 HB Ⅲ and 5 HB Ⅳ. The amplitude changes under supramaximal stimulation after tumor removal were 12.9%-100%, average (63.9±25.7)%. The facial function outcomes were poor (HB Ⅳ) in the cases whose intraoperative amplitude decreases were more than 70%. Different postoperative facial function group showed significantly different intraoperative amplitude changes (F=7.585, P=0.001), except HB Ⅰ group and HB Ⅱ group. The existence of cystic degeneration showed strong correlation (r=-0.635) to the amplitude changes, the level of tumor adhesion showed moderately negative correlation (r=-0.455), and tumor size showed weak negative correlation (r=-0.292), surgical approach and the facial nerve course pattern were not statistically relevant.

CONCLUSIONS

The amplitude change of facial nerve supramaxial stimulation can predict the postoperative facial function. The amplitude change is valuable for early treatment of facial nerve damage.

Plasmonic reflection color filters with metallic random nanostructures

We develop reflective color filters with randomly distributed nanodisks and nanoholes fabricated with hydrogen silsesquioxane and Ag films on silicon substrate. They exhibit high resolution, angle-independence and easily up-scalable fabrication, which are the most important factors for color filters for industrial applications. We uncover the underlying mechanism after systematically analyzing the localized surface plasmon polariton coupling in the electric-field distribution. The agreement of the experimental results with those from the simulation indicates that tunable colors across the visible spectrum can be obtained by simply varying the diameter of the nanodisks, promoting their applications.

Nanoindentation modulus of murine cartilage: a sensitive indicator of the initiation and progression of post-traumatic osteoarthritis

OBJECTIVE

This study aims to demonstrate that cartilage nanoindentation modulus is a highly sensitive indicator of the onset and spatiotemporal progression of post-traumatic osteoarthritis (PTOA) in murine models.

DESIGN

Destabilization of the medial meniscus (DMM) surgery was performed on the right knees of 12-week old male, wild-type C57BL/6 mice, with Sham control on contralateral left knees. Atomic force microscopy (AFM)-based nanoindentation was applied to quantify the nanoindentation modulus, Eind, of femoral condyle cartilage at 3 days to 12 weeks after surgery. The modulus changes were compared against the timeline of histological OA signs. Meanwhile, at 8 weeks after surgery, changes in meniscus, synovium and subchondral bone were evaluated to reveal the spatial progression of PTOA.

RESULTS

The modulus of medial condyle cartilage was significantly reduced at 1 week after DMM, preceding the histological OA signs, which only became detectable at 4-8 weeks after. This reduction is likely due to concomitantly elevated proteolytic activities, as blocking enzymatic activities in mice can attenuate this modulus reduction. In later OA, lateral condyle cartilage and medial meniscus also started to be weakened, illustrating the whole-organ nature of PTOA.

CONCLUSIONS

This study underscores the high sensitivity of nanoindentation in examining the initiation, attenuation and progression of PTOA in murine models. Meanwhile, modulus changes highlight concomitant changes in lateral cartilage and meniscus during the advancement of OA.

[Application of gadolinium enhanced magnetic resonance imaging of inner ear to observe bilateral inner ears hydrops in patients with unilateral Meniere's disease]

Objective:Department of Otolaryngology Head and Neck Surgery,Xinhua Hospital,Shanghai Jiaotong University School of Medicine,Shanghai Jiaotong University Ear Institute,Shanghai,200092,China This study was designed to study the correlation between endolympahatic hydrops image results and auxiliary examinations by magnetic resonance imaging after intratympanic administration of gadolinium in both ears in unilateral Meniere's disease patients.Meanwhile,the contralateral endolympahatic hydrops of the "asym ptomatic " ear in patients with unilateral Meniere's was also observed.Method:Thirty-one patients with unilateral Meniere's disease were enrolled in this study.All the patients underwent pure tone audiometry,electrocochleography(ECochG),cervical-vestibular evoked myogenic potentials(cVEMP) before intratympanic gadolinium contrast agents injected.All the patients underwent three-dimensional fast fluid attenuated inversion recovery sequence magnetic resonance imaging(3D-FLAIR MRI) after intratympanic gadolinium contrast agents injected 24 hours.The images were graded in accordance with the severity of endolympatic hydrops.Spearman correlation analysis was performed between the scores of the images and results of auxiliary examination results.Meanwhile,Student's t test was performed for the significance test of the age,duration of the disease and the hearing level of the affected ears between the group with contralateral endolympatic hydrops and the group without contralateral endolympatic hydrops.Result:Pure tone average and the degree of the cochlear hydrops(r=0.383,P <0.05),the SP/AP ratio and the degree of the cochlear hydrops(r=0.496,P<0.01),and interaural amplitude difference and the degree of the vestibular hydrops(r=0.635,P<0.01) showed a significant correlation.The duration of the disease[(6.7±6.3) years vs(2.9±3.1) years,P <0.05] and the hearing level of the affected ear[(70.3±7.4)dB vs(52.5±3.8)dB,P <0.05)] showed a significant difference between the group with contralateral endolympatic hydrops and the group without contralateral endolympatic hydrops.Conclusion:Pure tone average and the degree of the cochlear hydrops,-SP/AP ratio and the degree of the cochlear hydrops,and interaural amplitude difference and the degree of the vestibular hydrops also showed a significant correlation,which suggesting that MRI image can reflect the auditory-vestibular function in patients with Meniere's disease.Endolympatic hydrops and hearing loss are closely related,but not necessarily result in Meniere's disease symptoms.Patients with longer duration of the disease and worse hearing in the affected ears are more likely to develop bilateral endolympatic hydrops.

Contrast-enhanced ultrasound for differential diagnosis of malignant and benign ovarian tumors: systematic review and meta-analysis

OBJECTIVE

To assess the performance of contrast-enhanced ultrasound (CE-US) in the differential diagnosis of malignant and benign ovarian tumors.

METHODS

We conducted a comprehensive literature search of PubMed and EMBASE to identify published articles evaluating the diagnostic potential of CE-US for the differentiation of benign and malignant ovarian tumors. Inclusion criteria were: (1) the study assessed the accuracy (or sensitivity and specificity) of CE-US for diagnosis of benign and malignant ovarian tumors; (2) it used surgery and histopathology as the reference standard for distinguishing between benign and malignant tumors; (3) it included data allowing construction of a 2×2 contingency table for true- and false-positives and negatives. We present summary sensitivity, specificity, diagnostic odds ratio (OR) and areas under the summary receiver-operating characteristics curves (AUCs).

RESULTS

Preliminary screening identified 103 papers, of which 11 fulfilled our predefined inclusion criteria and underwent final analysis. The pooled sensitivity and specificity of CE-US for diagnosis of benign and malignant ovarian tumors were 93% (95% CI, 89-96%) and 95% (95% CI, 92-96%), respectively. The pooled diagnostic OR was 171.2 (95% CI, 65.9-444.6) and the AUC was 0.98. I(2) values of sensitivity, specificity and diagnostic OR were 38.3%, 31.7% and 48.4%, respectively, all indicating moderate heterogeneity.

CONCLUSIONS

The evidence from available studies suggests CE-US is useful for discriminating between benign and malignant ovarian tumors; however, further studies are needed to examine whether CE-US has improved diagnostic test accuracy compared with that of standard two-dimensional Doppler sonography.

Is intramedullary nailing better than the use of volar locking plates for fractures of the distal radius? A meta-analysis of randomized controlled trials

We conducted a meta-analysis of randomized controlled trials that compared the use of intramedullary nails and volar locking plates in distal radial fractures. PubMed, EMBASE and the Cochrane Collaboration Central database were used to find randomized controlled trials that met the eligibility criteria. Two reviewers screened the studies, extracted the data, evaluated the methodological quality and analysed the data with RevMan 5.1 software. No statistically significant differences were detected in the disability of the arm, shoulder and hand and the Gartland and Werley scores, radiographic parameters, wrist range of motion, grip strength, total complication rate and incidence of tendon rupture between the two groups. However, carpal tunnel syndrome occurred less often after intramedullary nailing. The two fixation methods achieved equal clinical, functional and radiological outcomes for primary fixation of the indicated types of distal radial fractures.

LEVEL OF EVIDENCE

Therapeutic/LevelI.

Diagnosis of latent tuberculosis by ELISPOT assay and tuberculin skin test

OBJECTIVE

To determine the prevalence of latent tuberculosis infection (LTBI) in college students.

PATIENTS AND METHODS

Four hundred and twenty newly admitted college students were enrolled. The Enzyme-Linked ImmunoSpot assay (ELISPOT) was used. Overall, 171 students with ELISPOT assay+/TST+ were monitored for three years to detect active TB disease.

RESULTS

The overall positive rate of ELISPOT assay was 40.7% among TST+ students. The ELISPOT positive rates were 36.9%, 45.4%, and 64.3% in groups of TST induration of 10-14mm, 15-20mm, and ≥20mm, respectively, with a significant difference (χ(2)=10.136, P<0.01) but no significant difference between BCG scar and no scar (41.2% vs. 38.8%; P>0.05). None of the 171 untreated students contracted active TB within the three-year monitoring period.

CONCLUSION

The LTBI rate might be overestimated by TST compared with interferon-γ release assays. On the basis of a close monitoring, few students developed active TB despite a positive result to the TST and ELISPOT assay.

Evidence for Octupole Correlations in Multiple Chiral Doublet Bands

Two pairs of positive-and negative-parity doublet bands together with eight strong electric dipole transitions linking their yrast positive- and negative-parity bands have been identified in ^{78}Br. They are interpreted as multiple chiral doublet bands with octupole correlations, which is supported by the microscopic multidimensionally-constrained covariant density functional theory and triaxial particle rotor model calculations. This observation reports the first example of chiral geometry in octupole soft nuclei.

Magnetic field enhanced upconversion luminescence and magnetic–optical hysteresis behaviors in NaYF4: Yb, Ho nanoparticles

A magnetic field induces the enhancement of upconversion luminescence and magnetic–optical hysteresis behaviors in NaYF₄: 20% Yb, 1% Ho nanoparticles.