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81.
Kuroiwa M Hatakeyama SI Suzuki N Murai H Toki F Tsuchida Y 《Asian journal of surgery / Asian Surgical Association》2004,27(1):43-48
OBJECTIVE: Ultrasound (US) has been used as a tool to determine the indication for surgery for neonatal ovarian cysts. The purpose of this study was to investigate whether magnetic resonance imaging (MRI) contributes to optimal management. METHODS: Between 1993 and 2001, US and MRI studies were simultaneously performed on 13 consecutive infants younger than 2 months of age with ovarian cysts. The US Patterns were classified as complex or simple. Signal intensity (SI) of the cysts on MRI was compared with that of the liver on T1-weighted images (T1WI) and with urine on T2-weighted images (T2WI). We assumed that high SI on T1WI and iso or low SI on T2WI indicated complications. RESULTS: There were 10 complex and three simple cysts on US. Of the 10 complex cysts, two had no complications at surgery or resolved spontaneously. These two cysts showed low SI on T1WI. Eight complex cysts showed high SI on T1WI and all were haemorrhagic. The US diagnosis corresponded to the MRI findings in three simple cysts. The sensitivity of US for haemorrhage was 80%, and that of MRI was 100%. CONCLUSIONS: We found that MRI was a more reliable diagnostic modality than US for diagnosing neonatal ovarian cysts. 相似文献
82.
Numazaki H Tohyama H Nakano H Kikuchi S Yasuda K 《The American journal of sports medicine》2002,30(6):800-805
BACKGROUND: Initial graft tension influences clinical results of anterior cruciate ligament reconstruction. HYPOTHESIS: Under repetitive loading conditions, the effect of initial graft tension on the biomechanical behavior of the femur-graft-tibia complex may depend on the graft and the fixation. STUDY DESIGN: Ex vivo biomechanical laboratory study. METHODS: After anterior cruciate ligament reconstruction, initial graft tension of 20, 80, or 140 N was applied to the complex for 2 minutes. Then, a cyclic force-relaxation test was performed for 5000 cycles so that the graft was stretched by 2 mm. RESULTS: In a patellar tendon graft with interference screws, the average peak load values at the 5000 th cycle were 105, 157, and 205 N for the complexes with initial tension of 20, 80, and 140 N, respectively. In a flexor tendon graft with interference screws, the values were 27, 41, and 39 N. In a flexor tendon graft with Endobutton fixation, the values were 17, 40, and 77 N. CONCLUSIONS: Considering the tension of the normal anterior cruciate ligament (16 to 87 N), an initial tension of 20 N appears to be high enough for a patellar tendon graft. For a flexor tendon graft with interference screws, an increase in initial tension above 80 N has no biomechanical advantages. 相似文献
83.
Hideaki Nohara Tsutomu Shida Nobuhiko Mukohara Keitarou Nakagiri Masamichi Matsumori Kyoichi Ogawa 《Annals of thoracic and cardiovascular surgery》2004,10(1):54-56
We present an unusual case of acute type A dissection complicated with severe aortic valve insufficiency caused by prolapse of the tubular intimal flap into the left ventricular outflow tract, which was shown legibly by transesophageal echocardiography in the diastolic phase and by intraoperative macroscopic findings. The dissected ascending aorta was excised completely and replaced without any repairing of the aortic valve, resulting in a favorable outcome for the patient. Prolapse of an intimal flap from the aorta into the left ventricle represented a rare pathophysiology of aortic regurgitation in patients with aortic dissection. 相似文献
84.
Torigoe K Akai T Iida T Shiraga S Sasagawa Y Tachibana O Iizuka H 《No shinkei geka. Neurological surgery》2012,40(4):351-357
Hemangiopericytoma develops from many organs. In the central nervous system, most tumors arise in the intracranial portion, and tumors originating from the spinal cord are rare. Its clinical course and neurological characteristics have not been disclosed. We present a case of a 51-year-old woman with gradually progressing paraparesis. Magnetic resonance (MR) images of the thoracic spine demonstrated an intradural tumor at the 6 and 7 thoracic vertebral body level. The patient underwent total excision of the tumor. The histological diagnosis was hemangiopericytoma. MR images after the operation showed no residual tumor and the patient was followed up without adjuvant therapy. However, 5 years later, the patient complained of back pain and gait disturbance again, and MR images showed a recurrence of the tumor. We resected the tumor under motor evoked potential (MEP) monitoring and removed the extradural part of the tumor, but the part of the tumor which had infiltrated the spinal cord was left due to the lowering of MEP amplitude. The operation resulted in partial resection. Spinal intradural hemangiopericytoma is very rare, and only 15 cases including the present case have been reported. This paper will discuss the clinical characteristics and treatment for this tumor. 相似文献
85.
Goto SN Matsui M Manabe H Takagi H Umemoto T 《General thoracic and cardiovascular surgery》2012,60(3):157-160
We describe a 48-year-old man with aorto-pseudoaneurysm-ventricular regurgitation. It was due to disruption of both proximal
and distal anastomoses after aortic root replacement for detachment of a prosthetic valve implanted for a sinus of Valsalva
aneurysm with aortic valve regurgitation. The chest was opened during cardiopulmonary bypass using a deep hypothermic circulatory
arrest to avoid rupture of the aneurysm because of a close relation between the pseudoaneurysm and the sternum. Aortic root
re-replacement was performed successfully. 相似文献
86.
Akifusa Wada Tomoyuki Nakamura Toru Yamaguchi Haruhisa Yanagida Kazuyuki Takamura Yutaka Oketani Hideaki Kubota Toshio Fujii 《Journal of children's orthopaedics》2012,6(4):261-267
Purpose
Kabuki syndrome is characterized by distinctive facial features, skeletal anomalies, persisting fingertip pads with dermatoglyphic abnormalities, postnatal growth deficiency and mental retardation. This report reviews our results in the operative treatment of hip dislocations in patients with Kabuki syndrome.Methods
Between 2001 and 2009, seven dislocated hips (three unilateral and two bilateral hips) in five patients (all girls) were operatively treated at our institution. The operative treatment consists of open reduction, femoral derotation varus osteotomy, pelvic osteotomy (Salter in one and incomplete periacetabular osteotomy in six hips) and capsular plication. The age of the patients at the time of surgery ranged from 2.4 to 5.7 years, with an average of 3.6 years.Results
The follow-up postoperative period ranged from 3.2 to 6.3 years, with an average of 5.0 years. At the final follow-up, all patients reported no click and no pain, and showed well-contained hips by radiographs. All seven hips were graded as Severin class I-II. One patient presented as having habitual dislocation of the hip 4.4 years after surgery. Computed tomographic (CT) scans revealed posterior acetabular wall deficiency, which was not corrected by the anterolaterally directed Salter osteotomy. The incomplete periacetabular osteotomy provided sufficient posterolateral coverage of the acetabulum.Conclusion
Operative treatment combining open reduction, femoral derotation varus and incomplete periacetabular osteotomies, and capsular plication provided successful results in patients with Kabuki syndrome who had the characteristics of hip instability such as ligamentous laxity, muscular hypotonia and posterior acetabular wall deficiency. 相似文献87.
Yuka Takayanagi Satoshi Yuda Hideaki Sugio Maki Ichimura Hitomi Masuda-Yamamoto Norie Tanaka-Saito Tetsuji Miura 《Journal of Echocardiography》2012,10(3):101-103
We present a case of a rare combination of ventricular septal defect and atrial septal aneurysm (ASA) with a patent foramen ovale (PFO) in a 57-year-old female. She was referred to our hospital for the treatment of irregular palpitation and exertional shortness of breath. Two-dimensional transesophageal echocardiography (2D-TEE) with color Doppler imaging demonstrated an ASA with two lines of shunt flows. Three-dimensional transesophageal echocardiography (3D-TEE) could clearly visualize the morphology of the PFO in the surgeon??s view and demonstrated a crescent-shaped opening of the PFO. 3D-TEE appears to be a more accurate modality than 2D-TEE for the assessment of PFO. 相似文献
88.
BACKGROUND: Spinally administered clonidine produces analgesia via alpha2-adrenergic receptors. The analgesic potency of clonidine and its dependency on muscarinic acetylcholine receptors increase in rats after nerve injury. The authors hypothesized that these changes reflect greater acetylcholine release from the spinal cord by clonidine, either through direct or indirect effects. METHODS: Male Sprague-Dawley rats were divided into two groups: no surgery or left L5 and L6 spinal nerve ligation (SNL). All experiments were performed 3 weeks after SNL. Crude synaptosomes were prepared from the spinal enlargement and loaded with [H]choline. Samples were incubated with clonidine in the absence or presence of KCl depolarization. The authors also examined the effect of clonidine on KCl evoked acetylcholine release using perfusion of spinal cord slices, in which some spinal circuitry is maintained. RESULTS: In synaptosomes, clonidine alone induced minimal acetylcholine release, which was actually greater in tissue from normal rats than in tissue from SNL rats. In the presence of KCl depolarization, however, clonidine enhanced acetylcholine release in tissue from SNL rats but inhibited release in tissue from normal rats. Similarly, in spinal cord slices, clonidine enhanced KCl evoked acetylcholine release in tissue from SNL animals but inhibited such release in tissue from normal animals. The alpha2-adrenoceptor antagonist idazoxan inhibited the effects of clonidine in slices from SNL rats. CONCLUSION: These results suggest that clonidine enhances depolarization-induced acetylcholine release in neuropathic but not in normal spinal cord tissue. Interestingly, this enhanced acetylcholine release by clonidine occurs in a synaptosomal preparation, consistent with a direct effect on alpha2 adrenoceptors on cholinergic terminals. Enhanced release of acetylcholine by clonidine could contribute to increased analgesia of clonidine in neuropathic pain. 相似文献
89.
Hiroshi Saeki Hiroyuki Kuwano Hidetoshi Kawaguchi Kozo Sonoda Takefumi Ohga Kaoru Kitamura Hideaki Nakashima Yasushi Toh Keizo Sugimachi Toshio Oiwa 《Surgery today》1998,28(12):1254-1256
A Japanese man, who had undergone a subtotal esophagectomy reconstructed with a gastric tube through an antesternal route
for esophageal carcinoma 16 years previously, was admitted to our hospital because of an abdominal incisional hernia. The
abdominal incisional hernia was in his upper abdomen and was difficult to push back into the intraabdominal cavity by hand.
The hernia was successfully repaired by operation. We thus conclude that an abdominal incisional hernia is a rare but important
late-phase complication occurring after an esophagectomy reconstructed with either an antesternal or retrosternal route, and
an operation should be the treatment of choice. 相似文献
90.
Purpose To evaluate whether sevoflurane and isoflurane consumption would be actually halved by halving the carrier gas flow rate,
as predicted by a theoretical model, we measured the consumed volume of liquid sevoflurane and isoflurane and total costs
of anesthetic gas at carrier gas flow rates of 3 and 61·min−1.
Methods Eighty patients of ASA physical status I or II were randomly assigned to one of four groups: sevoflurane at 3 or 61·min−1 and isoflurane at 3 or 61·min−1. Anesthesia was induced with thiamylal and maintained with sevoflurane or isoflurane, as well as with nitrous oxide in oxygen.
The consumption of sevoflurane and isoflurane was measured by weighing the bottle of liquid agent, which was greater in the
groups receiving 61·min−1 gas than in those receiving 31·min−1.
Results Halving the carrier gas flow rate reduced the consumption of sevoflurane by 41.8% and that of isoflurane by 52.6%. It also
reduced the total cost by 44.3% for sevoflurane and 49.2% for isoflurane.
Conclusion Halving the carrier gas flow rates halved the consumption of isoflurane but not of sevoflurane, indicating that factors other
than carrier gas flow rates are involved in determining consumption in the clinical setting. 相似文献