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51.
A prospective trial was undertaken to evaluate the efficacy of stimulated in-vitro fertilization (SIVF) and stimulated intrauterine insemination (SIUI) in couples with unexplained and mild male factor infertility. In all, 80 couples were allocated to treatment with SIVF or SIUI, both treatments following the same protocol [clomiphene citrate and follicle stimulating hormone (FSH) injection], except that higher doses of FSH were used in the SIVF treatment cycles. Initially, 41 couples were allocated to and started treatment with SIVF but eight cases were eventually converted to SIUI because of under-response. Similarly, although 39 couples were initially allocated to SIUI treatment, five of these converted to SIVF because of over-response. The treatment cycles that were converted either to SIUI or to SIVF were not considered as treatment failures but as treatment changes and so were included in the analyses. Of the final 38 SIVF cycles, four were cancelled (dysfunctional response), failed fertilization occurred in five cycles and 29 subjects reached embryo transfer. There were two biochemical pregnancies [positive human chorionic gonadotrophin (HCG) only], two clinical abortions and seven live births. Of the final 42 SIUI cycles, only two were cancelled, insemination being performed in the remaining 40 cases. The result was one clinical abortion, three ectopics and eight live births. The proportion of cycles with positive HCG was identical (28.9% per cycle treated for SIVF and 28.6% for SIUI) and the livebirth rates were also not different (18.4% per cycle treated for SIVF and 19.0% for SIUI). The cost per maternity of SIUI was approximately half that of SIVF (Pounds Sterling 1923 versus Pounds Sterling 4611) and so we conclude that, as SIUI had an efficacy that was not significantly different from SIVF (using similar protocols) but was more cost-effective, it must be considered the more appropriate form of management for the treatment of unexplained and mild male factor infertility. Indeed, it is hard to justify the routine use of IVF, as a first approach, in unexplained infertility.   相似文献   
52.

Purpose

Variability in functional outcome after ileal pouch-anal anastomosis (IPAA) is to a large extent unexplained. The aim of this study was to use MRI to evaluate the morphology, emptying pattern and other pathology that may explain differences in functional outcome between well-functioning and poorly functioning pouch patients. A secondary aim was to establish a reference of normal MRI findings in pelvic pouch patients.

Methods

From a previous study, the best and worst functioning patients undergoing IPAA surgery between 2000 and 2013 had been identified and examined with manovolumetric tests (N?=?47). The patients were invited to do a pelvic MRI investigating pouch morphology and emptying patterns, followed by a pouch endoscopy.

Results

Forty-three patients underwent MRI examination. We found no significant morphological or dynamic differences between the well-functioning and poorly functioning pouch patients. There was no correlation between urge volume and the volume of the bony pelvis, and no correlation between emptying difficulties or leakage and dynamic MRI findings. Morphological MRI signs of inflammation were present in the majority of patients and were not correlated to histological signs of inflammation. Of the radiological signs of inflammation, only pouch wall thickness correlated to endoscopic pouchitis disease activity index scores.

Conclusion

It seems MRI does not increase the understanding of factors contributing to functional outcome after ileal pouch-anal anastomosis. Unless there is a clinical suspicion of perianal/peripouch disease or pelvic sepsis, MRI does not add value as a diagnostic tool for pelvic pouch patients. Endoscopy remains the golden standard for diagnosing pouch inflammation.
  相似文献   
53.

Purpose

To compare the clinical performance of upper abdominal PET/DCE-MRI with and without concurrent respiratory motion correction (MoCo).

Methods

MoCo PET/DCE-MRI of the upper abdomen was acquired in 44 consecutive oncologic patients and compared with non-MoCo PET/MRI. SUVmax and MTV of FDG-avid upper abdominal malignant lesions were assessed on MoCo and non-MoCo PET images. Image quality was compared between MoCo DCE-MRI and non-MoCo CE-MRI, and between fused MoCo PET/MRI and fused non-MoCo PET/MRI images.

Results

MoCo PET resulted in higher SUVmax (10.8?±?5.45) than non-MoCo PET (9.62?±?5.42) and lower MTV (35.55?±?141.95 cm3) than non-MoCo PET (38.11?±?198.14 cm3; p?<?0.005 for both). The quality of MoCo DCE-MRI images (4.73?±?0.5) was higher than that of non-MoCo CE-MRI images (4.53±0.71; p?=?0.037). The quality of fused MoCo-PET/MRI images (4.96?±?0.16) was higher than that of fused non-MoCo PET/MRI images (4.39?±?0.66; p?<?0.005).

Conclusion

MoCo PET/MRI provided qualitatively better images than non-MoCo PET/MRI, and upper abdominal malignant lesions demonstrated higher SUVmax and lower MTV on MoCo PET/MRI.
  相似文献   
54.

Purpose

Endovascular stents are widely used for the elective treatment of cerebral aneurysms. Acute stenting is performed in the management of dissections, pseudo-aneurysms, broad-based aneurysms or as a ‘bail out’ measure after coil migration. The purpose of this study is to review the safety of using stents in acute subarachnoid haemorrhage.

Methods

The stent registry of our institution was reviewed for procedures in patients with acute subarachnoid haemorrhage. Imaging studies were reviewed on the hospital’s PACS system and the patients’ notes were retrieved to assess complications and clinical outcomes. Procedures were analysed according to the type of stent, treatment indication, antiplatelet regime, complications and outcomes.

Results

Between 2008 and 2016, 51 stents were placed during 50 stenting procedures in 49 patients with acute subarachnoid haemorrhage. This included 24 patients with saccular aneurysms, 10 with blister aneurysms, 10 dissections and five fusiform aneurysms. Stents were deployed in ‘bail out’ situations on eight occasions. In six cases, flow-diverting stents were used. Eighteen patients (37%) in the cohort suffered a stroke. Nine patients (18%) suffered persistent clinical deficits as a result of the stenting procedure, all but one of which occurred within 24 h. Two patients had a transient ischaemic episode, and there was evidence of asymptomatic ischaemia on imaging in four cases (8%). Five patients died, three (6%) as a result of procedural complications. Twelve patients (25%) required a further embolisation procedure.

Conclusion

The use of stents in acute subarachnoid haemorrhage incurs a considerable complication risk and should be reserved for exceptional circumstances.
  相似文献   
55.

Objectives

To evaluate the ability of arterial spin labelling perfusion-weighted imaging (ASL-PWI) to identify reperfusion status and to predict the early neurological outcome of acute ischaemic stroke patients after intra-arterial (IA) thrombectomy.

Methods

A total of 51 acute ischaemic stroke patients who underwent IA thrombectomy were retrospectively reviewed. Asymmetrical index before and after IA thrombectomy (AICBFpre and AICBFpost) and volume ratio of the reperfused territory to the baseline perfusion abnormality (reperfusion volume ratio) were calculated on ASL-PWI. A paired t-test was used to compare AICBFpre and AICBFpost. Pearson correlation and multiple linear regression were performed to evaluate correlations between the imaging parameters and NIHSS scores.

Results

Mean AICBFpost was significantly higher than mean AICBFpre (0.923±0.352 vs. 0.312±0.191, p<0.001). AICBFpre had a significant correlation with NIHSSpre (pr=–0.430, p=.004). ?AICBF had significant correlations with NIHSS24 h, NIHSS5-7 days and ?NIHSS5-7 days (r=–0.356, p=0.028; r=–0.597, p<0.001; r=–0.346, p=0.033, respectively). ?AICBF, reperfusion volume ratio and baseline infarct volume were significant independent predictors for NIHSS5-7 days.

Conclusions

ASL-PWI has the potential to serve as a non-invasive imaging tool to monitor the reperfusion status and predict the early neurological outcome of acute ischaemic stroke patients after IA thrombectomy.

Key Points

? CBF change on ASL-PWI after IA thrombectomy correlated with NIHSS scores. ? ASL-PWI can non-invasively monitor reperfusion in AIS patients after IA thrombectomy. ? ASL-PWI may predict early outcome of AIS patients after IA thrombectomy.
  相似文献   
56.

Background Context

The most commonly used materials used for interbody cages are titanium metal and polymer polyetheretherketone (PEEK). Both of these materials have demonstrated good biocompatibility. A major disadvantage associated with solid titanium cages is their radiopacity, limiting the postoperative monitoring of spinal fusion via standard imaging modalities. However, PEEK is radiolucent, allowing for a temporal assessment of the fusion mass by clinicians. On the other hand, PEEK is hydrophobic, which can limit bony ingrowth. Although both PEEK and titanium have demonstrated clinical success in obtaining a solid spinal fusion, innovations are being developed to improve fusion rates and to create stronger constructs using hybrid additive manufacturing approaches by incorporating both materials into a single interbody device.

Purpose

The purpose of this study was to examine the interbody fusion characteristic of a PEEK Titanium Composite (PTC) cage for use in lumbar fusion.

Study Design/Setting

Thirty-four mature female sheep underwent two-level (L2–L3 and L4–L5) interbody fusion using either a PEEK or a PTC cage (one of each per animal). Animals were sacrificed at 0, 8, 12, and 18 weeks post surgery.

Materials and Methods

Post sacrifice, each surgically treated functional spinal unit underwent non-destructive kinematic testing, microcomputed tomography scanning, and histomorphometric analyses.

Results

Relative to the standard PEEK cages, the PTC constructs demonstrated significant reductions in ranges of motion and a significant increase in stiffness. These biomechanical findings were reinforced by the presence of significantly more bone at the fusion site as well as ingrowth into the porous end plates.

Conclusions

Overall, the results indicate that PTC interbody devices could potentially lead to a more robust intervertebral fusion relative to a standard PEEK device in a clinical setting.  相似文献   
57.
58.
Right lobe living donor liver transplantation (RLDLT) is not yet a fully accepted therapy for patients with end-stage liver failure in the Western hemisphere because of concerns about donor safety and inferior recipient outcomes. An outcome analysis from the time of listing for all adult patients who were listed for liver transplantation (LT) at our center was performed. From 2000 to 2006, 1091 patients were listed for LT. One hundred fifty-four patients (LRD; 14%) had suitable live donors and 153 (99%) underwent RLDLT. Of the remaining patients (DD/Waiting List; n = 937), 350 underwent deceased donor liver transplant (DDLT); 312 died or dropped off the waiting list; and 275 were still waiting at the time of this analysis. The LRD group had shorter mean waiting times (6.0 months vs. 9.8 months; p < 0.001). Although medical model for end-stage liver disease (MELD) scores were similar at the time of listing, MELD scores at LT were significantly higher in the DD/Waiting List group (15.4 vs. 19.5; p = 0.002). Patients in Group 1 had a survival advantage with RLDLT from the time of listing (1-year survival 90% vs. 80%; p < 0.001). To our knowledge, this is the first report to document a survival advantage at time of listing for RLDLT over DDLT.  相似文献   
59.
Biliary strictures remain the most challenging aspect of adult right lobe living donor liver transplantation (RLDLT). Between 04/2000 and 10/2005, 130 consecutive RLDLTs were performed in our center and followed prospectively. Median follow-up was 23 months (range 3-67) and 1-year graft and patient survival was 85% and 87%, respectively. Overall incidence of biliary leaks (n = 19) or strictures (n = 22) was 32% (41/128) in 33 patients (26%). A duct-to-duct (D-D) or Roux-en-Y (R-Y) anastomosis were performed equally (n = 64 each) with no difference in stricture rate (p = 0.31). The use of ductoplasty increased the number of grafts with a single duct for anastomosis and reduced the biliary complication rate compared to grafts >/=2 ducts (17% vs. 46%; p = 0.02). Independent risk factors for strictures included older donor age and previous history of a bile leak. All strictures were managed nonsurgically initially but four patients ultimately required conversion from D-D to R-Y. Ninety-six percent (123/128) of patients are currently free of any biliary complications. D-D anastomosis is safe after RLDLT and provides access for future endoscopic therapy in cases of leak or stricture. When presented with multiple bile ducts, ductoplasty should be considered to reduce the potential chance of stricture.  相似文献   
60.
OBJECTIVE: To test the hypothesis that antioxidants might affect local inflammation by impairing inflammatory cell influx. DESIGN: A laboratory study using a Swiss-Webster mouse model of local inflammation. SETTING: A university-affiliated hospital. METHODS: Intradermal injection of 30 micrograms of S. minnesota endotoxin (LPS) to Swiss-Webster mice initiates a local inflammatory reaction characterized by an early rise in vascular permeability and a later infux of neutrophils. Animals were pretreated intraperitoneally with either pyrrolidine dithiocarbamate (PDTC, 2 mmol/kg), which inhibits free radical generation, or dimethylthiourea (DMTU, 450 mg/kg), a free radical scavenger. MAIN OUTCOME MEASURES: Histologic findings of tissue samples taken at sites of injection; local changes in tissue vascular permeability (PI) determined by iodine-125 albumin injection before sacrifice; neutrophil accumulation quantified by tissue myeloperoxidase levels; tissue levels of the endothelial adhesion molecules intercellular adhesion molecule-1 protein (ICAM-1) and vascular cell adhesion molecule-1 protein (VCAM-1) assessed by immunohistochemistry and Western blot, respectively. RESULTS: Neither antioxidant had a significant effect on the early increase in PI, but both decreased the late rise in PI and reduced neutrophil influx. Both ICAM-1 and VCAM-1 were upregulated in response to LPS; however, only the increase in VCAM-1 was attenuated by antioxidant pretreatment. CONCLUSION: These data suggest that antioxidants disrupt the propagation phase of an inflammatory response possibly by altering neutrophil migration.  相似文献   
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