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81.
Assessment of optic nerve and optic tract alterations in patients with orbital space-occupying lesions using probabilistic diffusion tractography
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Chun-Nan Wu Shao-Feng Duan Xue-Tao Mu Yi Wang Peng-Yu Lan Xiao-Lu Wang Kun-Cheng Li 《国际眼科》2019,12(8):1304-1310
AIM: To investigate the diffusion changes in both the optic nerve and optic tract in orbital space-occupying lesion patients with decreased visual acuity, and its clinical significance using probabilistic diffusion tractography (PDT).
METHODS: Twenty patients with orbital space-occupying lesions and 25 age- and gender-matched healthy persons were included. All patients and controls underwent routine orbital magnetic resonance imaging and diffusion tensor imaging (DTI), using a 3.0T magnetic resonance scanner (Trio Tim Siemens). After the image data were preprocessed, each DTI parameters of the optic nerve and optic tract was obtained by PDT, including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD). The asymmetry index (AI) of each parameter was calculated. Compared the parameters of the affected side optic nerve and ipsilateral optic tract with the contralateral side by paired sample t-test; compared AI of parameters of optic nerve and optic tract between the patient group and the control group by independent sample t-test. Patients were divided into three subgroups according to the low vision grade standard of WHO, compared the FA and AI of FA between the three subgroups by single factor variance analysis.
RESULTS: The affected side optic nerve presented significantly decreased FA, increased MD, AD, and RD values compared to the unaffected side (P<0.05). The AI of FA, MD, AD, and RD of optic nerve in the patients was significantly higher than that of the controls (P<0.05). The comparison results of the optic tract showed that there was no significant difference between the patient group and control group in terms of the bilateral optic tracts in patients (P>0.05). The AIs of the FA value of the optic nerve in the eyesight <0.1 subgroup was significantly higher than that in the other groups (P<0.05).
CONCLUSION: FA, MD, AD, and RD of the affected side optic nerve of the orbital space-occupying lesions have significantly changed, the FA value is the most sensitive. The PDT could be a useful tool to provide valid quantitative markers of optic nerve injuries and evaluate the severity of orbital diseases, which other examinations cannot be acquired. 相似文献
82.
Evaluation of extrashort 4‐mm implants in mandibular edentulous patients with reduced bone height in comparison with standard implants: a 12‐month results
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83.
Early and late implant failure of submerged versus non‐submerged implant healing: A systematic review,meta‐analysis and trial sequential analysis
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84.
《Cochlear implants international》2013,14(4):183-196
AbstractThe aim of this study was to use Speech Pattern Audiometry (SPA) to compare phoneme perception performance between SPEAK and ACE processing strategies with children using the Nucleus 24 cochlear implant. Listeners were evaluated in terms of ability to identify two synthetic word pairs, one signalling a voicing contrast and the other signalling a place of articulation contrast. For both word pairs, ACE was associated with more ‘normal’ phoneme boundaries than SPEAK. There was also a nonsignificant trend for better identification ability with ACE compared to SPEAK. The study suggests that there may be a place for SPA as part of the clinical battery of tests used for evaluation of cochlear implant speech processing strategies in children. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
85.
86.
《Annals of medicine》2013,45(2):167-169
Experience with the contraceptive NORPLANT in Egypt dates back to early 1980 when the first multicentre trial was initiated. To date, more than 3000 women have received this contraceptive at the Assiut University Family Clinic alone. Analysis of the overall experience in this clinic has indicated a 5-year cumulative continuation rate of 51 and a pregnancy rate of 1.8 per 100 women.Clinical pharmacology studies pertaining to the safety of NORPLANT in our community have indicated no deleterious effect on the lipid profile, liver functions and blood coagulation system. Two studies conducted in Egypt have indicated that the initiation of NORPLANT use shortly after delivery does not have any unfavourable effect on lactational performance, or on physical or psychomotor development of the breast-fed infants. This is particularly important in Arab and Moslem cultures where prolonged breast-feeding is emphasized.A study utilizing focus-group discussion to assess users' attitudes to NORPLANT has indicated the need to improve the informational/educational package given in the service by emphasizing certain cultural considerations.On the whole, this first implant method has proven to be safe and acceptable in Egypt, where there is a special need for long-term methods for contraception, particularly as sterilization is not socially acceptable. 相似文献
87.
88.
N. Fernández‐Formoso B. Rilo M. J. Mora I. Martínez‐Silva A. M. Díaz‐Afonso 《Journal of oral rehabilitation》2012,39(11):830-837
The etiologic factors associated with crestal bone loss have not been comprehensively clarified. Several theories exist as to the reason for the observed changes in crestal bone height following implant restoration. In the 1990s, the wide‐diameter implants were commercially introduced. Initially, the implants were restored with standard‐diameter abutments because of lack of matching prosthetic components. Long‐term radiographic follow‐up of these ‘platform‐switched’ restored wide‐diameter dental implants has demonstrated a smaller‐than‐expected vertical change in the crestal bone height around these implants that is typically observed around implants restored conventionally with prosthetic components of matching diameters. The aim of this randomised controlled study was to assess radiographically marginal bone level alterations in implants restored according to the platform‐switching concept compared with traditionally restored implants. Fifty‐four subjects to participate in this randomised controlled study were selected. Two groups were assigned at random: control group (56 implants were restored with standard matching‐diameter abutments) and test group (58 implants were restored with medialised abutments). X‐ray explorations were taken for peri‐implant bone level at the minute the last cementing of the prosthesis and at 1‐year follow‐up. NHI Image was used to digitally process and manipulate the radiographic images and perform the measurements. Mean of bone loss with platform‐switching implants was ?0·01 mm, and the mean of bone loss with standard platform implant was 0·42 mm. Outcomes of this study indicated that the platform‐switching design could preserve the crestal bone levels to 1‐year follow‐up. There was a statistically significant difference in marginal bone loss. 相似文献
89.
《Seminars in Arthroplasty》2017,28(3):140-144
Modern shoulder arthroplasty techniques include hemiarthroplasty, total shoulder arthroplasty (TSA), and reverse shoulder arthroplasty (RSA). Out of all arthroplasty procedures, total shoulder arthroplasty produces more satisfactory outcomes for osteoarthritis and inflammatory arthropathy (Sanchez-Sotelo, 2011 [1]). As shoulder arthroplasty procedures continue to increase in popularity, so do revision surgeries (revision TSAs and revision RSAs). Implants used in shoulder arthroplasty procedures have been transformed substantially from generation to generation, going from 1st to 4th generation implants. We propose 5th generation convertible implants that enable a more patient-specific, anatomic reconstruction with the potential to solve major issues that exist with implants from previous years. 相似文献
90.
《Journal of plastic surgery and hand surgery》2013,47(4):308-312
AbstractIn recent years the acellular dermal matrix (ADM) has gained popularity in prosthetic breast reconstruction. These procedures involve placement of a closed suction drain in the reconstructed breast. Although it is now widely accepted that ADM has an overall positive effect on the outcome of breast reconstruction, data regarding its effect on postoperative drain secretions is lacking. This study was designed to quantitatively evaluate the influence of ADM on postoperative drain secretions in the setting of immediate prosthetic breast reconstruction (IPBR). This is a prospective, comparative controlled study. Two groups of 16 patients each underwent skin sparing mastectomies (SSM) and IPBR with or without ADM. Closed suction drains were left in all the reconstructed breasts and daily secretion volumes were recorded and compared. Postoperative complications were also noted. Patients in the ADM group showed higher daily and overall secretion volumes compared with patients in the control group (p = 0.014) and the time for removal of the drains was higher by an average of 5 days (13 compared with 8 days, respectively; p = 0.004). There was no correlation between ADM and infection. This study provides the first objective evidence that ADM contributes to elevated and prolonged drain secretions when used for IPBR. This might affect possible prosthesis-related complications (e.g., rotation and malposition, capsular contraction, seroma formation, and infection). This study also noted erythema of the post-mastectomy skin flaps in selected patients, which may be attributable to a local inflammatory reaction to the ADM rather than infection. 相似文献