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81.
82.
Drug-induced parkinsonism is the second most common cause of parkinsonism after Parkinson's disease and their distinction has crucial implications in terms of management and prognosis. However, differentiating between these conditions can be challenging on a clinical ground, especially in the early stages. We therefore performed a review to ascertain whether assessment of non-motor symptoms, or use of ancillary investigations, namely dopamine transporter imaging, transcranial sonography of the substantia nigra, and scintigraphy for myocardial sympathetic innervation, can be recommended to distinguish between these conditions.Among non-motor symptoms, there is evidence that hyposmia can differentiate between patients with “pure” drug-induced parkinsonism and those with degenerative parkinsonism unmasked by an anti-dopaminergic drug. However, several issues, including smoking history and cognitive functions, can influence smell function assessment. Higher diagnostic accuracy has been demonstrated for dopamine transporter imaging. Finally, preliminary evidence exists for sympathetic cardiac scintigraphy to predict dopaminergic pathway abnormalities and to differentiate between drug-induced parkinsonism and Parkinson's disease.Imaging of the dopaminergic pathway seems to be the only, reasonably available, technique to aid the differential diagnosis between drug-induced parkinsonism and Parkinson's disease.  相似文献   
83.
Tendon injury is a known complication of distal radius fracture plate and screw fixation. Targeted musculoskeletal sonography is uniquely capable of assessing both tendon integrity and hardware abnormalities not recognized on radiographs. Each of the 3 patients described presented with pain after an open reduction–internal fixation following a distal forearm fracture. In each patient, radiographic findings, specifically the hardware position, were interpreted as normal. Important radiographically occult observations were subsequently made with sonography, including 3 proud screws and tendon injuries, all of which required surgical treatment. This case series demonstrates the clinical utility of musculoskeletal sonography in symptomatic patients after distal radius open reduction–internal fixation with negative radiographic findings. In our practice, sonography has been the most useful modality for precluding missing or delaying the diagnosis and treatment of these hardware complications. We advocate its use as an adjunct in any department performing musculoskeletal imaging.  相似文献   
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85.
Antral follicle count (AFC) is a reliable predictor of ovarian response to stimulation and its inter-cycle and inter-observer variability has been extensively studied on in vitro fertilization (IVF), mostly in highly selected populations within studies not originally designed for this purpose. In this retrospective cohort study, we assess the inter-cycle variation of AFC in a setting similar to that of the daily practice. We included only patients undergoing mild stimulation for intrauterine insemination (IUI). One hundred and forty-eight patients had two (62 patients, group A), three (49 patients, group B) or four (37 patients, group C) IUI cycles and AFC was measured on early follicular phase of each cycle by one of the members of the medical team within daily practice. Intra-class correlation coefficients were used to estimate variability. Inter-cycle variability rendered ICCs above 0.70 in all groups improving along with the number of cycles [Group A ICC 0.78 (95%CI 0.66–0.86), Group B ICC 0.87 (95%CI 0.80–0.92) and Group C ICC 0.91 (95%CI 0.85–0.95)]. Inter-observer variability showed a high degree of concordance with ICCs above 0.95. We provide the closest approximation to real inter-cycle and inter-observer AFC variability expected in routine clinical practice.  相似文献   
86.
87.
Contrast-transcranial Doppler and contrast-transcranial color-coded duplex sonography (c-TCCD) have been reported to have high sensitivity in detecting patent foramen ovale as compared with transesophageal echocardiography. An international consensus meeting (Jauss and Zanette 2000) recommended that the contrast agent for right-to left-shunt (RLS) detection using contrast-transcranial Doppler be prepared by mixing 9 mL of isotonic saline solution and 1 mL of air. The aim of our study was to determine whether adding blood to the contrast agent results in improved detection of RLS. We enrolled all consecutive patients admitted to our neurosonology laboratory for RLS diagnosis. For each patient, we performed c-TCCD both at rest and during the Valsalva maneuver using two different contrast agents: ANSs (1 mL of air mixed with 9 mL of normal saline) and ANSHBs (1 mL of air mixed with 8 mL of normal saline and 1 mL of the patient's blood). To classify RLS, we used a four-level visual categorization: (i) no occurrence of micro-embolic signals; (ii) grade I, 1–10 signals; (iii) grade II, >10 signals but no curtain; grade III, curtain pattern. We included 80 patients, 33 men and 47 women. RLS was detected in 18.8% at rest and in 35% during the Valsalva maneuver using ANSs, and in 31.3% and in 46.3% using ANSHBs, respectively (p < 0.0001). There was a statistically significant increase in the number of micro-embolic signals with the use of ANSHBs. The use of blood mixed with saline solution and air as a c-TCCD contrast agent produced an increase in positive tests and a higher grade of RLS compared with normal saline and air alone, either with or without the Valsalva maneuver.  相似文献   
88.
Renovascular hypertension is a clinical situation characterized by high blood pressure in the presence of renal ischemia mainly related to atherosclerotic or fibromuscular dysplasic narrowing of the renal artery (ies). This diagnosis is often “a posteriori” validated, because the discovery of a significant renal artery stenosis is not obligatory responsible of the blood pressure elevation.

This article proposes a diagnostic strategy for exploring patient with this suspected secondary cause of hypertension before proposing an invasive approach (intra-arterial angiography) possibly followed by a revascularization. However, the methods for exploring such population are mainly based on patient characteristics and local expertise and habits. These must thus be individualized. First, clinical symptoms or signs frequently associated with hypertension and renal artery stenosis must be searched. If present, a non invasive and functional exploration of the renal arteries is to be proposed (Captopril radioisotope renography, colour duplex sonography) followed by magnetic resonance angiography or spiral computer tomography angiography if the clinical suspicion index is moderate or high. If this is very high, an intraarterial arteriography could immediately be performed if not too dangerous. On the opposite site, if the clinical index is low, it is recommended to follow clinically and to treat risk factors.  相似文献   
89.
A device for the training and quantitative assessment of the competency of trainee radiologists in the technically challenging area of breast sonography was developed and evaluated. Currently, suitable commercially available devices are lacking, and there is a growing realization that the reliance on direct exposure to patients for learning may not represent best practice from either the trainees' or patients' perspective. Three devices (PI, PII and PIII) were designed to produce very realistic sonographic images of breast morphology with a range of embedded pathologies. The pilot evaluation used a case study research design to evaluate the role of the anthropomorphic breast sonography training device in training and assessment in a clinical environment. Through the case study, it was possible to evaluate the process and relationships when using this type of training intervention for a small group of radiology resident trainees. The investigation involved a baseline assessment of trainees' (n = 4) ability to detect and characterize all lesions in PI, followed by a 4-wk training period on PII and a post-training assessment using PIII. The evaluation revealed an improvement of 30% ± 8% in the trainee's performance from pre- to post-training. It was expected that the performance of the trainees would improve as the training phantom described in this study aligns with the learning theory of constructivism and fits the ideal specifications of a medical training device in terms of its realism and facilitation of self-directed learning and deliberate practice of the trainees. The device provides a useful platform upon which training and assessment can be facilitated.  相似文献   
90.
Engaging Hill‐Sachs lesions can be a factor predictive of recurrent anterior shoulder instability, yet no method has been recognized as an effective means to predict engagement. We evaluated the ability of sonography to identify engaging Hill‐Sachs lesions by using a transaxillary approach and dynamic scanning. In patients with engaging lesions, there was an abrupt change in the contour of the humeral head when the shoulder was in 90° of abduction and 90° of external rotation. Sonography therefore has the potential to be a useful preoperative tool in determining which patients may benefit from a surgical repair that also addresses Hill‐Sachs lesions.  相似文献   
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