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61.

Objectives

This study applied advanced 4-dimensional flow magnetic resonance imaging processing to assess differences in aortic flow dynamics after valve sparing root replacement, with and without reconstruction of the Valsalva sinuses.

Methods

We enrolled patients after valve sparing root replacement with a straight tubular prosthesis (n = 10) or with a prosthesis with Valsalva neosinuses (n = 10); age-matched subjects without cardiovascular diseases served as controls (n = 10). 4-Dimensional flow magnetic resonance imaging acquisitions were performed on a 3.0T magnetic resonance imaging unit. In-house processing was used to segment the aortic lumen and extract the volumetric 4-dimensional flow velocity field. Velocity flow streamlines were computed to compare the amount of rotational flow and wall shear stress. Occurrence of abnormal wall shear stress (WSS) was estimated within the descending aorta of each surgical group.

Results

Physiologic-like sinus vortices were visible in the aortic root when using the prosthesis with neosinuses, whereas straight tubular graft revealed localized intrados malrotations (P = .003 for organized vortical structures vs neosinuses graft and P < .001 vs control). In the ascending aorta, recreation of the sinuses resulted in significantly lower velocity and WSS than in the straight tubular graft (P < .001) and controls (P < .001), these alterations were attenuated in the mid-descending aorta. Incidence of abnormal WSS was markedly higher in the straight tube grafts than neosinus of Valsalva grafts.

Conclusions

Re-creation of the sinuses of Valsalva during valve-sparing root replacement is associated with more physiologic flow and significantly lower WSS in the aortic root. Lower WSSs in the distal thoracic aorta is a novel finding with potential implications on distal aortic remodeling.  相似文献   
62.
Skin sensitivity is a serious problem for many people, and it can be induced by various factors such as UV irradiation, physical and mental stresses, air pollution, dry air and so on. Skin dryness triggered by UV and dry air is one of the most important causes inducing the development of sensitive skin, and it has been reported that oxidative stress contributes to skin dryness. In this study, we investigated whether treatment with 3‐O‐laurylglyceryl ascorbate (VC‐3LG), which is an amphipathic ascorbic acid derivative, can suppress the development of sensitive skin. The results demonstrate that VC‐3LG restores the expression levels of interleukin‐1α, nerve growth factor and matrix metalloprotease‐9 in the dry skin models of reconstructed human epidermal equivalents (RHEEs) and in H2O2‐treated keratinocytes. In addition, VC‐3LG suppresses the dendrite elongation of nerve cells induced in RHEEs by dry skin conditions and by H2O2 treatment of keratinocytes. Therefore, we consider that treatment of the skin with VC‐3LG is an effective approach to improve the development of sensitive skin.  相似文献   
63.
目的 研究视神经炎患者的临床特征及早期视盘和黄斑的改变。方法 回顾性分析山西省眼科医院视神经炎患者67例85眼。分析患者基本情况、眼科检查结果及OCT检查结果。结果 67例85眼中,男24例,女43例;28例(41.8%)发生于冬季;49眼(57.6%)入院时最佳矫正视力小于1.7 logMAR。视神经脊髓炎抗体阳性者出院和入院时的最佳矫正视力均较髓鞘少突胶质糖蛋白抗体阳性者差。患眼较健眼视盘周围神经纤维层增厚,杯盘面积比、杯盘垂直比、杯盘水平比、杯容积减小,盘沿面积、视盘面积增大(均为P=0.000);与健眼相比,患眼早期上方、下方和平均黄斑区神经节细胞层厚度及黄斑区神经节细胞复合体的局部丢失体积、整体丢失体积均未发生明显改变(均为P>0.05)。视盘水肿与患眼平均视盘周围神经纤维层厚度存在正相关(r=0.728,P=0.000)。结论 视神经炎多发生于女性,早期视力损害严重,视神经脊髓炎抗体阳性者视力预后差。早期由于视盘水肿,视盘周围神经纤维层增厚,盘沿面积、视盘面积增大;杯容积、杯盘比减小,早期病变未累及黄斑区。  相似文献   
64.

Objectives

Post-thoracotomy pain leads to patient discomfort, pulmonary complications, and increased analgesic use. Intercostal nerve injury during thoracotomy or its entrapment during closure can contribute to post-thoracotomy pain. We hypothesized that a modified technique of posterolateral thoracotomy and closure, preserving the intercostal neurovascular bundle, would reduce acute and chronic post-thoracotomy pain.

Methods

We randomized 90 patients undergoing posterolateral thoracotomy for pulmonary resection at a tertiary level oncology center to standard posterolateral (control arm) or modified nerve-sparing thoracotomy. All patients received morphine via patient-controlled analgesia pumps. The primary outcome was the worst postoperative pain score in the first 3 postoperative days. Secondary outcomes included the average pain score and analgesic requirements in the first 3 postoperative days and the incidence of post-thoracotomy pain 6 months after surgery.

Results

No significant differences were seen between the groups in acute or chronic post-thoracotomy measured by the numeric rating scale. There was no difference seen in the worst (mean) postoperative pain scores (3.71 vs 3.83, difference 0.12; 99% confidence interval [CI], ?0.7 to +0.9; P = .7), average (mean) pain scores in the first 3 postoperative days (1.77 vs 1.85, difference 0.08; 99% CI, ?0.4 to +0.6; P = .69), mean consumption of morphine (mg/kg) (1.45 vs 1.40, difference ?0.05; 99% CI, ?0.4 to +0.3; P = .73), or incidence of chronic postoperative pain (37.8% vs 40%, difference 4.9%; 99% CI, ?22.8 to +30.7%; P = .73).

Conclusions

The modified nerve-sparing thoracotomy technique does not reduce post-thoracotomy pain compared with standard posterolateral thoracotomy.  相似文献   
65.
66.
67.
68.
Angioleiomyoma is a solitary form of leiomyoma which is typically encountered in the subcutis. They are mostly seen in lower extremities, and the upper extremity is the second most common location for these lesions. There are only a few reports about the presence of an angioleiomyoma within a peripheral nerve in the upper extremity. Here we report a 56-year-old male patient who was referred to our clinic after an attempt was made for removal of a forearm mass at another institution. The lesion was encased within the median nerve and there was an unusual hypervascularity around the tumor with numerous vessels entering the lesion. Removal of the tumor without apparent damage to nerve fascicles was possible. Histopathological examination of the excision material revealed an intraneural angioleiomyoma. Following surgery, the patient was free of any functional deficits and no evidence of recurrence was observed at one year follow-up. There is no data regarding recurrence in intraneural lesions due to the lack of a large series. It would not be wrong to recommend spare grossly uninvolved fascicles if the nerve in question is not expendable.  相似文献   
69.
70.

BACKGROUND CONTEXT

Cervical laminectomy and fusion (CLF) is a common surgical option for multilevel cord compression. Postoperative C5 palsy occurrence after CLF has been a vexing problem for spine physicians. The posterior shift of the cord following laminectomy has been implicated as a major factor for postoperative C5 palsy, but attempts by spine surgeons to mitigate excessive shift while providing sufficient decompression have not been well reported.

PURPOSE

To compare the incidence of postoperative C5 palsy after performing selective blocking laminoplasty concurrently with CLF to those of conventional CLF.

STUDY DESIGN

A retrospective comparative study of prospectively collected data.

PATIENT SAMPLE

Of 116 cervical myelopathy patients with degenerative cervical myelopathy, ossification of the posterior longitudinal ligament, and multilevel disc herniation, 93 patients (69 in group A [CLF group] and 24 in group B [selective blocking laminoplasty with CLF, CLF-S group]) were included in the study.

OUTCOME MEASURES

The primary outcome measure was the occurrence of postoperative C5 palsy. Secondary end points included (1) clinical outcomes based on pain intensity, neck disability index (NDI), Japanese Orthopaedic Association (JOA) score, (2) radiologic outcomes including cervical alignment and fusion rate at 1 year and hardware complications, and (3) perioperative data (hospital stay, blood loss, and operative times).

METHODS

We compared the occurrence of postoperative C5 palsy, as well as clinical, radiologic, and surgical outcomes, between the two groups at 1-year follow-up.

RESULTS

The patients in both groups were statistically similar between the groups with respect to demographic characteristics such as age, sex, smoking status, body mass index, preoperative pathology, surgical segments, and the degree of the cervical lordosis. Postoperative C5 palsy developed in 9 of 61 patients (14%) in group A and in 0 of 24 patients (0%) in group B (CLF-S group) (p=.03). Postoperative neck pain, NDI, and JOA improvement were not significantly different between the two groups (p=.93, 0.90, and 0.79, respectively). Perioperative data did not differ significantly between the two groups.

CONCLUSIONS

This study showed that performing selective blocking laminoplasty might lead to reducing the incidence of postoperative C5 palsy in CLF surgery.  相似文献   
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