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51.
BACKGROUND: The time for femoral lengthening is shortened if external fixation is combined with intramedullary nailing. However, several complications have been reported with this procedure. PATIENTS AND METHODS: We retrospectively reviewed the outcome of femoral lengthening performed over an intramedullary nail using external fixation in 22 patients. These patients were followed for a mean of 3.2 (2-5.2) years. The mean age was 22 (13-35) years at the time of the index procedure. The mean lengthening was 5 (2.7-8.1) cm and the external fixator was removed after median 20 (8-30) weeks. The mean external fixation index was 24 (11-35) days/cm and the mean consolidation index was 43 (26-55) days/cm of lengthening. RESULTS: 3 patients who had a past history of infection or open trauma developed osteomyelitis which required removal of the nail. There were 4 knee joint complications when the lengthening was over 20%, including posterior knee subluxation and patella subluxation. In 1 patient, the lengthened segment collapsed with breakage of locking screws. INTERPRETATION: Although lengthening over a nail can reduce the duration of external fixation, caution is required to prevent major complications.  相似文献   
52.
When infection of prosthetic orthopedic implants is suspected, optimal management requires accurate confirmation or exclusion of infection. The authors retrospectively studied 98 patients with possible infection who underwent scanning with indium-111-labeled white blood cells (WBCs) and subsequently underwent surgery within 14 days. At surgery, 50 patients had infections, as determined by means of culture or histologic results. The diagnostic accuracy of In-111 scanning was compared with that of plain radiography, arthrography, three-phase bone scanning, and various clinical and laboratory findings classically associated with infection. Positive findings on In-111 WBC scans and elevated erythrocyte sedimentation rates were found to be the most predictive variables in the diagnosis of septic prostheses (P less than or equal to .001 and P less than or equal to .002, respectively). Likelihood ratio analysis more clearly demonstrated the superiority of In-111 WBC scanning, with positive and negative scans yielding likelihood ratios of 5.0 and 0.16, respectively.  相似文献   
53.
AIM: To evaluate the clinical outcomes of V4c implantable collamer lens (Hole ICL) implantation with regard to the optical quality assessed according to different degrees of decentering. METHODS: This included 49 eyes that received conventional ICL and 94 eyes that received Hole ICL. The eyes that received Hole ICL were divided into three groups according to the degree of decentering: group 1, central hole within 1 hole diameter (HD) from the pupil center; group 2, central hole within 1 HD to 2 HD; and group 3, central hole within 2 HD to 3 HD. Visual acuity (VA), intraocular pressure (IOP), and spherical equivalent (SE) values were assessed at 1wk, 1 and 3mo after surgery. The ocular modulation transfer function, Strehl ratio, objective scattering index, and higher order aberrations (HOAs) were measured for 4-mm pupils at 3mo after surgery. RESULTS: There were no significant differences in VA, IOP, and SE among the conventional and Hole ICL groups. With regard to HOAs, values for coma and spherical aberrations showed no differences. The total HOA and trefoil values were significantly higher in group 2 than in group 1 (P=0.02, 0.03, respectively). There were no significant differences among groups with regard to other optical quality parameter at 3mo after surgery. CONCLUSION: Our results suggest that Hole ICL implantation provides satisfactory visual quality that is equivalent to that provided by conventional ICL, regardless of the presence of central hole and degree of decentering.  相似文献   
54.
55.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence.  相似文献   
56.
We report the sonographic appearance of a rare case of neuritis ossificans of the median nerve at the wrist, which appeared as a hyperechoic lesion around the nerve. Diagnosis was confirmed with magnetic resonance imaging (MRI).  相似文献   
57.
A solitary adrenal gland spanning the midline has been alternatively described as “Horseshoe” or “Butterfly” and is a rare congenital abnormality almost exclusively associated with neonates. There have been 65 reported cases in fetuses and infants, based on ultrasound and autopsy findings. Horseshoe adrenal gland is associated with several congenital anomalies, such as asplenia (52 %), neural tube defects (37 %), renal abnormalities (29 %), and diaphragmatic defects (1 %). Recently, Feldman and colleagues [2] reported the first case of an adult male with horseshoe adrenal gland and posterior midline diaphragmatic anomaly found incidentally with CT imaging. We present a second case of asymptomatic adult horseshoe adrenal gland with posterior midline diaphragmatic hernia in a 51-year-old woman discovered on CT imaging. In our patient these abnormalities were also associated with a 9th thoracic butterfly vertebrae and a unilateral region of underdevelopment of the paraspinal musculature at the level of the diaphragmatic defect. To our knowledge, this is the first time this abnormality has been documented with MRI.  相似文献   
58.
PurposeTo compare image quality in selective intracoronary contrast-injected computed tomography angiography (Selective-CTA) with that in conventional intravenous contrast-injected CTA (IV-CTA).Materials and MethodsSix pigs (35 to 40 kg) underwent both IV-CTA using an intravenous injection (60 mL) and Selective-CTA using an intracoronary injection (20 mL) through a guide-wire during/after percutaneous coronary intervention. Images of the common coronary artery were acquired. Scans were performed using a combined machine comprising an invasive coronary angiography suite and a 320-channel multi-slice CT scanner. Quantitative image quality parameters of CT attenuation, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), mean lumen diameter (MLD), and mean lumen area (MLA) were measured and compared. Qualitative analysis was performed using intraclass correlation coefficient (ICC), which was calculated for analysis of interobserver agreement.ResultsQuantitative image quality, determined by assessing the uniformity of CT attenuation (399.06 vs. 330.21, p<0.001), image noise (24.93 vs. 18.43, p<0.001), SNR (16.43 vs. 18.52, p=0.005), and CNR (11.56 vs. 13.46, p=0.002), differed significantly between IV-CTA and Selective-CTA. MLD and MLA showed no significant difference overall (2.38 vs. 2.44, p=0.068, 4.72 vs. 4.95, p=0.078). The density of contrast agent was significantly lower for selective-CTA (13.13 mg/mL) than for IV-CTA (400 mg/mL). Agreement between observers was acceptable (ICC=0.79±0.08).ConclusionOur feasibility study in swine showed that compared to IV-CTA, Selective-CTA provides better image quality and requires less iodine contrast medium.  相似文献   
59.
BackgroundThis study aimed to determine if sleep disturbances may mediate the relationship between panic symptoms and depression in patients with panic disorder (PD).MethodsElectronic medical records were retrospectively reviewed for 110 consecutive patients with diagnosed PD in an outpatient clinic between October 2018 and December 2019. Measurements include the PD Severity Scale, Beck Depression Inventory-II (BDI-II) and Insomnia Severity Index (ISI). Statistical analyses were performed to assess any potential relationship between PD, insomnia and depression.ResultsOf the PD patients, 88 (80%) and 89 (80.9%) had comorbid depression (BDI-II ≥ 14) and insomnia (Korean version of the ISI ≥ 8), respectively. In a mediation model using insomnia as the mediating variable, the total effect of panic symptom severity on depression was significant (t = 7.23, P < 0.001). There were significant effects of panic symptoms on insomnia (t = 4.62, P < 0.001) and of insomnia on depression (t = 6.69, P < 0.001). The main effect of panic symptom severity on depression was also significant, after controlling for the effect of insomnia (t = 5.10, P < 0.001), suggesting partial mediation.ConclusionBoth depressive symptoms and insomnia are common in patients with PD and depression was partially mediated by insomnia in these patients. These results suggest that an intervention for insomnia in patients with PD might help prevent the development of depression.  相似文献   
60.
Objective:This study investigated the usefulness of quantitative parameters [longitudinal relaxation (T1), transverse relaxation (T2), and proton density (PD)] obtained with synthetic magnetic resonance imaging (MRI) in assessing the progression of temporomandibular joint (TMJ) disorders.Methods:For individual TMJ disorder diagnoses, the presence of disc displacement in MRI and the osseous change in cone-beam CT were investigated. Joints were classified into three stages: (1) silent stage, no disc displacement or osseous change; (2) incipient stage, presence of disc displacement and absence of osseous change; and (3) progressed stage, both disc displacement and osseous change. In synthetic MRI, the T1, T2, and PD values of the condyle bone marrow were measured simultaneously. The median T1, T2, and PD values were analyzed according to disc displacement, osseous changes, and joint stage.Results:Significant differences were observed in the T1 and PD values of joints with disc displacement or condylar osseous change compared to normal joints. The T1 and PD values also differed between the silent and progressed stages. The PD value differed between the silent and incipient groups, while the T2 value did not differ significantly among the three groups.Conclusion:The PD and T1 values of condylar bone marrow obtained from synthetic MRI can be used as sensitive indicators of TMJ disorder progression. The PD value of the bone marrow showed potential as a useful biomarker for recognizing the initial stages of TMJ disorders. Synthetic MRI is useful for the simultaneous acquisition of effective MRI parameters for evaluating TMJ disorders.  相似文献   
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