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991.
The purpose of this review is to determine if there is a difference in outcomes after: (1) nonsurgical vs surgical treatment of FAI; (2a) surgical dislocation with greater trochanteric osteotomy, (2b) anterior mini-open, (2c) arthroscopic plus mini-open, and (2d) arthroscopic surgery for FAI; (3) difference in complication and re-operation rates; and (4a) labral refixation and (4b) labral debridement for labral injuries. A systematic review of multiple databases was performed after PROSPERO registration and using PRISMA guidelines. Level I-IV evidence clinical studies with minimum 2-year follow-up were included. Data were compared using 2-sample and 2-proportion Z-test calculators. Study methodological quality was analyzed using Modified Coleman Methodology Score (MCMS). Recommendations were made using SORT (Strength Of Recommendation Taxonomy). Twenty-nine studies were included (2369 subjects; 2507 hips). MCMS was poor. Mean subject age was 34.4+/−8.4 years and mean follow-up was 3.1+/−0.9 years. Statistically significant differences were observed following both nonsurgical and surgical treatment, with greater (P < 0.05) improvements following surgery (SORT B), without consistent significant differences observed between different surgical techniques (SORT C). There was a greater (P < 0.05) reoperation and complication rate following surgical dislocation vs mini-open and arthroscopic techniques (SORT A). Clinical outcomes were significantly better (P < 0.05) following labral refixation vs debridement (SORT B). Outcomes of operative treatment of femoroacetabular impingement are significantly better than nonsurgical management. Surgical treatment significantly improves outcomes, with no consistent significant differences exhibited between open and arthroscopic techniques. Open surgical dislocation has significantly greater reoperation and complication rates vs mini-open and arthroscopic techniques. Outcomes of labral refixation are significantly better than debridement in patients with labral injuries.  相似文献   
992.
Purpose: To determine the association between material dehydration and hydrogel contact lens material characteristics, including water content and ionicity. Methods: Water content and refractive index data were derived from automated refractometry measurements of worn hydrogel contact lenses of 318 participants in the Contact Lens and Dry Eye Study (CLADES). Dehydration was determined in two ways; as the difference between nominal and measured (1) water content and (2) refractive index. Multiple regression models were used to examine the relation between dehydration and material characteristics, controlling for tear osmolality. Results: The overall measured and nominal water content values were 52.58 ± 7.49% and 56.88 ± 7.81% respectively, while the measured and nominal refractive indices were 1.429 ± 0.015 and 1.410 ± 0.017. High water content and ionic hydrogel lens materials were associated with greater dehydration (p < 0.0001 for both) than low water content and non‐ionic materials. When dehydration was assessed as the difference in refractive index, only high water content was associated with dehydration (p < 0.0001). Conclusions: High water content and ionic characteristics of hydrogel lens materials are associated with hydrogel lens dehydration, with the former being more strongly associated. Such dehydration changes could in turn lead to important clinical ramifications such as reduced oxygen transmissibility, greater lens adherence and reduced tear exchange.  相似文献   
993.
Suture anchors are increasingly gaining importance in rotator cuff surgery. This means they will be gradually replacing transosseous sutures. The purpose of this study was to compare the stability of transosseous sutures with different suture anchors with regard to their pullout strength depending on bone density. By means of bone densitometry (CT scans), two groups of human humeral head specimens were determined: a healthy and a osteopenic bone group. Following anchor systems were being tested: SPIRALOK™ 5.0 mm (resorbable, DePuy Mitek), Super Revo 5 mm (titanium, Linvatec), UltraSorb (resorbable, Linvatec) and the double U-sutures with Orthocord™ USP 2 (partly resorbable, DePuy Mitek) and Ethibond Excel 2 (non-resorbable, Ethicon). The suture anchors/double U-sutures were inserted in the greater tuberosity 12 times. An electromechanical testing machine was used for cyclic loading with power increasing in stages. We recorded the ultimate failure loads, the system displacements and the modes of failure. The suture anchors tended to bring about higher ultimate failure loads than the transosseous double U-sutures. This difference was significant in the comparison of the Ethibond suture and the SPIRALOK 5.0 mm—both in healthy and osteopenic bone. Both the suture materials and the SPIRALOK 5.0 mm showed a significant difference in pullout strength on either healthy or osteopenic bone; the titanium anchor SuperRevo 5 mm and the tilting anchor UltraSorb did not show any significant difference in healthy or osteopenic bone. There was no significant difference concerning system displacement (healthy and osteopenic bone) between the five anchor systems tested. The pullout strength of transosseous sutures is neither on healthy nor on osteopenic bone higher than that of suture anchors. Therefore, even osteopenic bone does not constitute a valid reason for the surgeon to perform open surgery by means of transosseous sutures. The choice of sutures in osteopenic bone is of little consequence anyway since it is mostly the bone itself which is the limiting factor.  相似文献   
994.
995.
The lacrimal gland is the primary source for the aqueous portion of the tear film. This portion contains water, electrolytes and proteins, which are necessary for the health and maintenance of the cells of the ocular surface. Afferent sensory nerves in the cornea and conjunctiva stimulate efferent parasympathetic and sympathetic nerves in the lacrimal gland. Cholinergic agonists, released from parasympathetic nevres, and norepinephrine, released from sympathetic nerves, are major stimuli of lacrimal gland secretion. These neurotransmitters activate distinct, but overlapping signal transduction pathways leading to lacrimal gland secretion. Other stimuli of lacrimal gland secretion are the EGF family of growth factors. In addition to stimulation of secretion, these growth factors can interact with the cells of the lacrimal gland themselves or with the cells of the ocular surface depending upon the location from which these growth factors are released. This review will focus on the effects of the EGF family of growth factors on the lacrimal gland and their interactions with the pathways stimulated by the neurotransmitters released from nerves.  相似文献   
996.
The lipid layer of tears: dependent on meibomian gland function   总被引:9,自引:0,他引:9  
There is growing laboratory and clinical evidence implicating the meibomian glands of the eyelid as playing a critical role in the pathogenesis of various ocular surface disorders such as chronic blepharitis and dry eye. Meibomian glands produce a lipid material whose synthesis is dependent on factors such as stem cells, neurological stimulants and hormones. This lipid material is fluid, spreads easily, is a surfactant as well as an aqueous barrier, and must remain functional after a blink. Before delivery it can be modified by factors such as hormone abnormalities and even after delivery it may be modified by lipases produced by ocular bacteria.  相似文献   
997.
Objective MRI detects subchondral marrow findings in painful knees which bear resemblance to spontaneous osteonecrosis of the knee (SONK). Gathering evidence suggests that the primary or predominant pathogenesis of these lesions is physical stress. This study analyzes the patient characteristics and meniscal pathology associated with these lesions—herein referred to as presumptive subarticular stress related (PSSR) lesions.Design and patients All patients were scanned using a standardized imaging protocol. The criterion for a PSSR lesion was a subchondral marrow edema pattern encompassing a more focal, low-signal zone adjacent to or contiguous with the subchondral cortex. Patients were identified using an electronic database search of cases reported by one experienced musculoskeletal radiologist.Results Twenty-five PSSR lesions were identified among 1,948 MRI evaluations of the knee. Twenty-one PSSR lesions occurred in the medial compartment, and four occurred in the lateral compartment. There was no sex predilection. Patients with PSSR lesions were older than other patients undergoing MRI evaluation (mean 66 years versus 52 years, P<0.001). Meniscal tears occurred more commonly in cases with PSSR lesions than in the group as a whole (76% versus 45%, P<0.001). Radial and posterior root tears were more common in knees with PSSR lesions than in other knees with meniscal tears (53% versus 26%, P<0.01).Conclusions PSSR lesions are associated with meniscal tears and, more specifically, with meniscal tear patterns that dramatically increase contact forces across the knee joint. This observation supports the hypothesis that mechanical stress is important in the pathogenesis of these subarticular lesions that are detected by MRI.  相似文献   
998.
Introduction The goal of this study is to determine whether suturing is superior to non-closure in terms of the subjective long-term outcome in large rotator cuff tears.Materials and methods A total of 64 shoulders with rotator cuff tears of at least 3 cm diameter and followed up for a mean period of 5 years and 8 months were retrospectively examined. The patients medical history, clinical findings, radiographs and Constant scores were studied. Patients whose tears had been closed with an open suture (n=33) were compared with those whose tears had not been closed (n=31).Results Neither the comparison between open suturing and debridement nor that between open and arthroscopic debridement reveal a significant difference with regard to the overall Constant score or the individual parameters.Conclusion These results suggest that in the long-term, suturing of large rotator cuff tears is not superior to debridement.  相似文献   
999.
PURPOSE: To report a case of retinal pigment epithelial tear treated by macular translocation with 360 degrees retinotomy. METHODS: Interventional case report. A 75-year-old woman with neovascular age-related macular degeneration and retinal pigment epithelial tear underwent macular translocation with 360 degrees retinotomy and silicone oil tamponade. After 3 months, pars plana vitrectomy, silicone oil removal, and muscle surgery were performed. RESULTS: Twenty-two months after macular translocation surgery, the visual acuity of the patient had improved to 20/50 (preoperative 20/200). No proliferative vitreoretinopathy or recurrence of the choroidal neovascularisation was observed. CONCLUSIONS: Macular translocation surgery with 360 degrees retinotomy can improve vision in retinal pigment epithelial tear secondary to neovascular age-related macular degeneration.  相似文献   
1000.
PURPOSE: To reduce venous contamination at the calf level in three-dimensional contrast-enhanced MR angiography (CE-MRA) by applying continuous infragenual cuff-compression. MATERIALS AND METHODS: Ten patients with clinically relevant peripheral arterial occlusive disease (PAOD) underwent dynamic three-dimensional CE-MRA of the calf. Six consecutive measurements were acquired with the first measurement serving as mask. Cuff-compression of 50 mmHg was attached below the knee. To allow intra-individual comparison, compression was applied unilaterally. The cuff was inflated three minutes before scanning and was continued throughout the MRA session. Venous contamination and arterial visualization scores were ranked using a five-point rating scale. Contrast-to-noise ratios (CNRs) of superficial enhancing calf-veins on the uncompressed and compressed calf sides were evaluated. An asymmetry index (AI) defined by CNR(mean) (uncompressed)/CNR(mean) (compressed) was introduced to describe the ratio in venous contrast agent supply between both sides quantitatively. RESULTS: Three-dimensional CE-MRA of the calves demonstrated significantly lower superficial venous contamination scores (P < 0.004) and clearly improved arterial visualization (P < 0.009) on the compressed side. Additionally, AI values were larger than 1 (P < 0.02), indicating a higher contrast agent supply in the superficial veins on the uncompressed side. CONCLUSION: Infragenual cuff-compression minimizes venous overlay in three-dimensional CE-MRA at calf level by reduction of contrast agent supply in the superficial veins.  相似文献   
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