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991.
992.
Vasim Farooq MBChB MRCP Mamas A. Mamas BM BCh MA DPhil MRCP Farzin Fath‐Ordoubadi MD FRCP Douglas G. Fraser MB BChir DM 《Catheterization and cardiovascular interventions》2011,78(6):847-863
Aims : Prior coronary artery bypass graft (CABG) surgery is one of the main predictors of failure of transradial PCI. Frequently this is due to difficulty in graft cannulation and/or poor backup support. In addition to Proxis's? embolic protection role, the Proxis?, Heartrail?, and GuideLiner? guide catheter extension devices have all been shown to facilitate coronary intervention by increasing backup support and aiding stent delivery. We describe our institution's experiences using these devices to aid transradial graft intervention. Methods : Between October 2007 and March 2010, the utility and safety of these devices were assessed in consecutive transradial graft intervention procedures. Proxis? cases used for proximal protection alone were excluded. Deep intubation was defined as an intubation depth of ≥2cm. Results : Guide catheter extensions were used in 33 of 41 transradial graft interventions identified. Proxis? was used for proximal protection alone in 3 cases, leaving 30 cases as the study group (Heartrail? n = 18, GuideLiner? n = 3, Proxis? n = 9). In all study cases procedural success with final TIMI‐3 flow was achieved. Guide catheter extensions were used to aid during graft cannulation (n = 11), to improve backup support via deep intubation (n = 26) and as an adjunctive aspiration device (n = 11). Filter‐based distal embolic protection devices were used in 11/21 Heartrail? and GuideLiner? cases. Deep intubation depths ranged from 30 to 138 mm (mean 61 mm) with no complications related to deep intubation seen. Conclusions : The use of guide catheter extension systems facilitated transradial graft intervention via several mechanisms including aid to graft cannulation, increasing backup support, and as an adjunctive aspiration device. © 2011 Wiley Periodicals, Inc. 相似文献
993.
L Vazquez Y Nizamaldin C Combescure R Nedir M Bischof DM Dohan Ehrenfest J-P Carrel UC Belser 《Dento maxillo facial radiology》2013,42(2)
Objectives:
Conventional panoramic radiography, a widely used radiographic examination tool in implant treatment planning, allows evaluation of the available bone height before inserting posterior mandibular implants. Image distortion and vertical magnification due to projection geometry is well described for rotational panoramic radiographs. To assess the accuracy of vertical height measurements on direct digital panoramic radiographs, implants and metal balls positioned in the posterior mandible were used as radio-opaque reference objects. The reproducibility of the measuring method was assessed by the inter- and intraobserver agreements.Methods:
Direct digital panoramic radiographs, performed using a Kodak 8000C (Eastman Kodak Company, Rochester, NY), of 17 partially edentulous patients (10 females, 7 males, mean age 65 years) were selected from an X-ray database gathered during routine clinical evaluation of implant sites. Proprietary software and a mouse-driven calliper were used to measure the radiological length of 25 implants and 18 metal reference balls, positioned in mandibular posterior segments. The distortion ratio (DR) was calculated by dividing the radiological implant length by the implant''s real length and the radiological ball height by the ball''s real height.Results:
Mean vertical DR was 0.99 for implants and 0.97 for balls, and was unrelated to mandibular sites, side, age, gender or observer. Inter- and intraobserver agreements were acceptable for both reference objects.Conclusions:
Vertical measurements had acceptable accuracy and reproducibility when a software-based calibrated measurement tool was used, confirming that digital panoramic radiography can be reliably utilized to determine the pre-operative implant length in premolar and molar mandibular segments. 相似文献994.
Harmandeep Singh MD Abhinav Singhal MD Punit Sharma MD Chetan D. Patel MD Sandeep Seth DM Arun Malhotra PhD 《Journal of nuclear cardiology》2013,20(3):415-425
Background
Data on normal parameters of cardiac mechanical synchrony is limited, variable and obtained from small cohorts till date. In most studies, software used for such assessment has not been mentioned. The aim of study is to establish normal values of mechanical synchrony with equilibrium radionuclide angiography (ERNA) in a larger population using commercially available software.Methods
We retrospectively analysed ERNA studies of 108 patients having low pretest likelihood of coronary artery disease, no known history of cardiac disease, normal electrocardiogram and whose ERNA studies were considered normal by experienced observers. In addition, ten patients diagnosed with dilated cardiomyopathy (DCM) and having LVEF ≤ 40% underwent ERNA. Fourier first harmonic analysis of phase images was used to quantify synchrony parameters using commercially available software (XT-ERNA). Intraventricular synchrony for each ventricle was measured as the standard deviation of the LV and RV mean phase angles (SD LVmPA and SD RVmPA, respectively). Interventricular synchrony was measured as LV-RVmPA. Absolute interventricular delay was calculated as absolute difference between LV and RVmPA (without considering ± sign). All variables were expressed in milliseconds (ms) and degree (°). Intra-observer and inter-observer variabilities were assessed. Cut-off values for parameters were calculated from the normal database, and validated against patient group.Results
On phase analysis, LVmPA was observed to be 343 ± 48.5 milliseconds (174.7° ± 18.5°), SD LVmPA was 16.3 ± 5.4 milliseconds (8.2° ± 2.5°), RVmPA was 339 ± 50.4 milliseconds (171.8° ± 18.5°) and SD RVmPA was 37.3 ± 15.7 milliseconds (18.7° ± 7.2°). LV-RVmPA was observed to be 3.9 ± 21.7 milliseconds (2.9° ± 9.6°) and absolute interventricular delay was 16.3 ± 14.8 milliseconds (7.9° ± 6.1°). The cut-off values for the presence of dyssynchrony were estimated as SD LVmPA > 27.1 milliseconds (>13.2°), SD RVmPA > 68.7 milliseconds (>33.1°) and LV-RVmPA > 47.3 milliseconds (>22.1°). There was no statistically significant intra-observer or inter-observer variability. Using these cut offs, 9 patients with DCM showed the presence of left intraventricular dyssynchrony, 5 had right intraventricular dyssynchrony and 2 had interventricular dyssynchrony.Conclusions
ERNA phase analysis offers an objective and reproducible tool to quantify cardiac mechanical synchrony using commercially available software and can be used in routine clinical practice to assess mechanical dyssynchrony. 相似文献995.
Tinea capitis in south-western Ethiopia: a study of risk factors for infection and carriage 总被引:1,自引:0,他引:1
Jose Ignacio Figueroa MD PhD Thomas Hawranek MD Aynalem Abraha MD Roderick James Hay DM FRCP FRCPath 《International journal of dermatology》1997,36(9):661-666
Background Tinea capitis is a common dermatophyte infection which constitutes an important public health problem among children worldwide. The endemic nature of scalp ringworm in Africa is perpetuated mainly by the lack of knowledge about the prevalence and carrier status, and the absence of control measures. Methods Two hundred and nineteen schoolchildren from urban and rural communities of the Illubabor district, south-western Ethiopia, were examined, and scalp samples were taken. Children were classified according to clinical signs and mycologic findings. Results Physical examination revealed that 29% of the children had clinical lesions compatible with tinea capitis. Dermatophytes were isolated from 33% of the children's scalp samples; of these, 16% had clinical lesions and 17% were identified as carriers. Trichophyton violaceum was responsible for 97% of infections. Conclusions Tinea capitis was the second most prevalent cutaneous finding in these children, with a higher prevalence in the urban community; the predictive value of the clinical diagnosis was low and a high proportion of children were identified as carriers in these communities. No relationship between household overcrowding and scalp infection was found. 相似文献
996.
997.
998.
ALEXANDER H HOON JR MD MPH ; ELAINE E STASHINKO PHD ; LIDIA M NAGAE MD ; DORIS DM LIN MD PHD ; JENNIFER KELLER MS PT ; AMY BASTIAN PHD ; MICHELLE L CAMPBELL MS ; ERIC LEVEY MD ; SUSUMU MORI PHD ; MICHAEL V JOHNSTON MD 《Developmental medicine and child neurology》2009,51(9):697-704
Aim Cerebral palsy (CP) is frequently linked to white matter injury in children born preterm. Diffusion tensor imaging (DTI) is a powerful technique providing precise identification of white matter microstructure. We investigated the relationship between DTI-observed thalamocortical (posterior thalamic radiation) injury, motor (corticospinal tract) injury, and sensorimotor function.
Method Twenty-eight children born preterm (16 males, 12 females; mean age 5y 10mo, SD 2y 6mo, range 16mo–13y; mean gestational age at birth 28wks, SD 2.7wks, range 23–34wks) were included in this case–control study. Twenty-one children had spastic diplegia, four had spastic quadriplegia, two had hemiplegia, and one had ataxic/hypotonic CP; 15 of the participants walked independently. Normative comparison data were obtained from 35 healthy age-matched children born at term (19 males, 16 females; mean age 5y 9mo, SD 4y 4mo, range 15mo–15y). Two-dimensional DTI color maps were created to evaluate 26 central white matter tracts, which were graded by a neuroradiologist masked to clinical status. Quantitative measures of touch, proprioception, strength (dynamometer), and spasticity (modified Ashworth scale) were obtained from a subset of participants.
Results All 28 participants with CP had periventricular white-matter injury on magnetic resonance imaging. Using DTI color maps, there was more severe injury in the posterior thalamic radiation pathways than in the descending corticospinal tracts. Posterior thalamic radiation injury correlated with reduced contralateral touch threshold, proprioception, and motor severity, whereas corticospinal tract injury did not correlate with motor or sensory outcome measures.
Interpretation These findings extend previous research demonstrating that CP in preterm children reflects disruption of thalamocortical connections as well as descending corticospinal pathways. 相似文献
Method Twenty-eight children born preterm (16 males, 12 females; mean age 5y 10mo, SD 2y 6mo, range 16mo–13y; mean gestational age at birth 28wks, SD 2.7wks, range 23–34wks) were included in this case–control study. Twenty-one children had spastic diplegia, four had spastic quadriplegia, two had hemiplegia, and one had ataxic/hypotonic CP; 15 of the participants walked independently. Normative comparison data were obtained from 35 healthy age-matched children born at term (19 males, 16 females; mean age 5y 9mo, SD 4y 4mo, range 15mo–15y). Two-dimensional DTI color maps were created to evaluate 26 central white matter tracts, which were graded by a neuroradiologist masked to clinical status. Quantitative measures of touch, proprioception, strength (dynamometer), and spasticity (modified Ashworth scale) were obtained from a subset of participants.
Results All 28 participants with CP had periventricular white-matter injury on magnetic resonance imaging. Using DTI color maps, there was more severe injury in the posterior thalamic radiation pathways than in the descending corticospinal tracts. Posterior thalamic radiation injury correlated with reduced contralateral touch threshold, proprioception, and motor severity, whereas corticospinal tract injury did not correlate with motor or sensory outcome measures.
Interpretation These findings extend previous research demonstrating that CP in preterm children reflects disruption of thalamocortical connections as well as descending corticospinal pathways. 相似文献
999.
Are current recommendations to diagnose orthostatic hypotension in Parkinson's disease satisfactory?
Jenny Jamnadas‐Khoda BMedSci Suma Koshy BSC Christopher J. Mathias DSC Uday B. Muthane DM Mona Ragothaman MBBS Subbakrishna K. Dodaballapur PhD 《Movement disorders》2009,24(12):1747-1751
We interviewed 50 Parkinson's disease (PD) patients using a questionnaire to verify the reliability of orthostatic symptoms in warning the presence of orthostatic hypotension (OH). OH is defined as 20 mm Hg systolic or 10 mm Hg diastolic BP fall within 3 min of tilting or standing but if this fall occurs after 3 min we called it ‘late OH’ (L‐OH). We compared if OH in Parkinson's disease (PD) was more frequent after head‐up tilt or on standing and if the period of postural challenge matters in detecting OH. Twenty‐one (42%) patients had OH that occurred twice more often after tilting (n = 20) than on standing (n = 10). OH occurred within 3 min of tilting in 9 patients (18%) and appeared beyond the currently recommended 3 min in 11 patients (55%) (L‐OH). Ten of the 20 patients developing OH on tilting were symptomatic. The 10 patients who had OH on standing were asymptomatic. Reporting of symptoms was independent of age or severity of BP fall. Most (90%) patients reporting orthostatic symptoms on standing had OH on tilting for 3 min. Orthostatic symptoms in PD have a high specificity but low sensitivity in predicting OH. In Parkinson's disease OH occurs often after tilting than on standing and is delayed (after 3 min). As OH in PD is often asymptomatic and delayed it could contribute to falls and increase morbidity. We suggest routine evaluation of OH in PD by tilting them longer than the recommended 3 minutes to detect delayed OH. © 2009 Movement Disorder Society 相似文献