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1.
目的:比较白内障微创超声乳化手术前后角膜前表面屈光力(ASF)、角膜真实净屈光力(TNP)和总角膜屈光力(TCRP)分布特点及角膜前后表面曲率半径比(B/F ratio)差异。

方法:前瞻性研究。收集2020-12/2021-05就诊于潍坊眼科医院行2.2mm微切口超声乳化白内障吸除联合人工晶状体植入术的年龄相关性白内障患者156例156眼。术前及术后3mo行Pentacam眼前节生物测量仪检查,收集以角膜顶点和以瞳孔为中心2、4、6mm环上和区域内ASF、TNP和TCRP,以及手术前后B/F ratio。

结果:术后3mo,以角膜顶点为中心2mm直径环上和区域内ASF值较术前均无差异(均P>0.05),而4、6mm直径环上和区域内ASF值较术前均有差异(均P<0.05); 以瞳孔为中心2mm直径环上及区域内ASF值较术前均无差异(均P>0.05)。以角膜顶点为中心和以瞳孔为中心2、4、6mm直径环上和区域内TNP、TCRP值较术前均有差异(均P<0.05)。术前以角膜顶点为中心和瞳孔为中心在2mm与6mm之间环上和4mm与6mm之间环上TCRP值均有差异(均P<0.0167); 在2mm与6mm区域内TCRP值均有差异(均P<0.0167); 术后3mo,以角膜顶点为中心和瞳孔为中心环上TCRP值在2mm与6mm之间、4mm与6mm之间均有差异(均P<0.0167),而以角膜顶点为中心和瞳孔为中心区域内TCRP值仅在2mm与6mm直径范围内有差异(P<0.0167)。B/F ratio术前为81.79%±1.87%,术后3mo为80.68%±2.23%(P<0.001)。

结论:白内障手术前后以角膜顶点和以瞳孔为中心的不同直径环上及区域内各项角膜屈光力参数会有一定的变化和差异,人工晶状体度数计算的K值选择及基于角膜特性的人工晶状体个体化选择时应予以考虑。  相似文献   

2.
This study was performed to compare the orbital and peri-orbital morphological variations in Apert syndrome patients with different cranial vault suture synostosis, so as to provide an anatomic basis for individualized surgical planning. Computed tomography scans of 57 unoperated Apert syndrome patients and 59 controls were subgrouped as follows: type I, bilateral coronal synostosis; type II, pansynostosis; type III, perpendicular combinations of cranial vault suture synostoses. Orbit bony cavity volume was significantly reduced in type I and type II, by 19% (P < 0.001) and 24% (P < 0.001), respectively. However, the reduction of orbital cavity volume in type III did not reach statistical significance. Globe volume projection beyond the orbital rim, however, increased by 76% (P < 0.001) in type III, versus an increase of 54% (P < 0.001) in type I and 53% (P < 0.001) in type II, due to different ethmoid and sphenoid bone malformations. Maxillary bone volume was only significantly reduced in type I bicoronal synostosis (by 24%, P = 0.048). Both type I and type II developed relatively less zygoma and sphenoid bone volume. Different cranial vault suture synostoses have varied influence on peri-orbital development in Apert syndrome. Instead of mitigating the abnormalities resulting from bicoronal synostosis in type I, additional midline suture synostosis worsens the exorbitism due to a more misshaped ethmoid.  相似文献   
3.

Purpose

To identify anatomical aberrations following PSARP procedure by using MRI, while correlating MRI findings to clinical outcome.

Patients and methods

Between January 2014 and December 2017, we conducted our study on male patients with rectourethral fistula who underwent PSARP. Postoperative pelvic MRI studies were performed and correlated to their clinical continence scores (Rintala, and Krickenbeck classification).

Results

The study included 31 patients. Fourteen patients were retrieved from the hospital records and accepted to participate in the study; while the remaining 17 were collected from the fecal incontinence clinic. Their age ranged from 40 to 156?months (mean 83) We divided patients in the study into two groups according to their Rintala continence scores: (Group A) 15 patients with low scores (10 or less); and (Group B) 16 patients with higher scores (more than 10). We detected wider pelvic hiatus (hiatus/PC ratio) and more obtuse anorectal angle in group A than B.

Conclusion

Several anatomical alterations can be detected by MRI following the PSARP procedure that include abnormalities in the striated muscle sphincter (attenuation/deficiency), deviated neorectum, and presence of excessive perirectal fat. A widened pelvic hiatus and/or obtuse anorectal angle may correlate with poor fecal continence in these patients.

Level of Evidence

This is a case control study (level III evidence).  相似文献   
4.
5.
目的:总结后颅窝正常和异常的胎儿小脑及小脑蚓部的矢状面的声像学特征,了解小脑细微结构的改变与胎儿畸形的关系。  相似文献   
6.
The purpose of this study was to assess the pre- and postoperative position and dimensions of the inferior alveolar canal (IAC) following sagittal split osteotomy (SSO) and identify any association with postoperative neurosensory deficit (NSD) at 1 year. This retrospective cohort study enrolled consecutive patients who had SSO performed to correct skeletal malocclusion. The pre- and postoperative cone beam computed tomography data were superimposed to visualize differences in IAC position and dimensions. Subjective and objective neurosensory tests were used to determine NSD in the inferior alveolar nerve distribution. A total of 20 subjects were included. The preoperative distance from the lateral cortex of the IAC to the inner aspect of the lateral cortex of the mandible was significantly greater in sides with NSD when compared to sides without NSD (P = 0.01). A significantly greater reduction in the postoperative distance measurement was seen in sides with NSD when compared to sides without NSD (P = 0.01). The magnitude of mandibular movement was significantly increased in sides with NSD (P = 0.02). The preoperative location of the IAC, as well as certain changes in the mediolateral and vertical positions as a result of SSO, are risk factors for postoperative NSD.  相似文献   
7.

Background

Biomechanics after total knee arthroplasty (TKA) often remain abnormal and may lead to prolonged postoperative recovery. The purpose of this study is to assess a biomechanical therapy after TKA.

Methods

This is a randomized controlled trial of 50 patients after unilateral TKA. One group underwent a biomechanical therapy in which participants followed a walking protocol while wearing a foot-worn biomechanical device that modifies knee biomechanics and the control group followed a similar walking protocol while wearing a foot-worn sham device. All patients had standard physical therapy postoperatively as well. Patients were evaluated throughout the first postoperative year with clinical measures and gait analysis.

Results

Improved outcomes were seen in the biomechanical therapy group compared to the control group in pain scores (88% vs 38%, P = .011), function (86% vs 21%, P = .001), knee scores (83% vs 38%, P = .001), and walking distance (109% vs 47%, P = .001) at 1 year. The therapy group showed healthier biomechanical gait patterns in both the sagittal and coronal planes at 1 year.

Conclusion

A postoperative biomechanical therapy improves outcomes following TKA and should be considered as an additional therapy postoperatively.  相似文献   
8.
The increase in the pharyngeal airway space after mandibular advancement has not been well explained, and in this study we aimed to show whether there is a correlation in the increase of pharyngeal airway space as a consequence of the mandibular advancement or of the relative change between the mandibular position and the natural head position (NHP). Fifteen patients who had bilateral sagittal split osteotomy for mandibular advancement with or without genioplasty were studied retrospectively. The primary variables of mandibular position, NHP, and pharyngeal airway space were measured in three dimensions using preoperative and postoperative cone-beam computed tomographic datasets and were compared using the paired t test. The secondary variable of pharyngeal airway space was defined as the square root of the mean cross-sectional area (CSA1/2) of the pharyngeal airway space. Pearson’s correlation coefficient was used to find out whether there was a correlation between the change in CSA1/2 and the change in mandibular position, or the relative change between the mandibular position and the NHP. Volumes and minimal cross-sectional areas were increased in the pharyngeal airway space, and lengths of airways decreased. Correlation existed only between the increase in CSA1/2 and the relative change between the mandibular position and NHP. The increase in pharyngeal airway space after mandibular advancement correlated with the relative changes between the mandibular position and the NHP.  相似文献   
9.
Historically, patients who received bilateral sagittal split osteotomies (BSSO) required an inpatient admission for at least one night. Since March 2015, the Oral and Maxillofacial Department at the Royal Gwent Hospital has performed bilateral sagittal split osteotomies (BSSO) as a day case procedure for their medically and socially fit patients. Our team’s service evaluation by Davies et al (2018) for this procedure, demonstrated that this could be done both routinely and successfully, whilst conforming to national day case procedural standards. The aim of this satisfaction survey was to evaluate this procedure from a patient’s perspective, to further consolidate our results from 2018. The forty-five patients who underwent day case BSSO (DCBSSO) between February 2015 and February 2020 were retrospectively identified and deemed eligible for inclusion. Participation involved completion of a 10-part questionnaire via telephone consultation. Patients were asked questions focussing on their experience of discharge timing, management of postoperative symptoms, and overall recovery at home. Twenty-four patients consented to partake in the survey (response rate of 73%). Twenty-three (96%) were extremely happy to be discharged the day of their surgery and felt that the timing of discharge was appropriate. Only 17% of patients experienced discomfort overnight and 96% of these stated they could manage their symptoms at home. From this survey, we can confirm that the majority of patients receiving DCBSSO at the Royal Gwent Hospital were happy to be discharged the day of their surgery and recover at home.  相似文献   
10.
The purpose of this study was to examine osseous healing in the cleavage between the bone fragments after sagittal splitting ramus osteotomy (SSRO) utilizing computed tomography (CT). The subjects were 13 patients with mandibular prognathism who underwent bilateral SSRO. CT was used to study the rami immediately after surgery, then 6 months, 1 year, and 2 years after surgery. Many concave type (the angle between the cleavage >90°) anterior borders developed into the stairway type (the angle between the cleavage <90°) 6-12 months after surgery. Few borders changed to the smooth type. Almost all of the stairway and concave posterior borders changed to the smooth type in the 6-12 months after surgery. Regarding the posterior borders 1 year after surgery, the cleavage of distal and proximal bone fragments demonstrated stable osseous healing (smooth type) in cases where the length and width between the bone fragments were large. In conclusion, the authors successfully demonstrated detailed osseous healing in the cleavage between the bone fragments after SSRO. Remodelling between bone fragments is a major mechanism of osseous healing after this procedure.  相似文献   
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