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1.
Ferdynand Hebal Elissa Port Catherine J. Hunter Bryan Malas Jared Green Marleta Reynolds 《Journal of pediatric surgery》2019,54(4):656-662
Background/purpose
Computed tomography (CT) derived Haller Index (HI) remains the standard for quantifying severity in patient with pectus excavatum (PE). Optical scanning described in literature reports optimistic results and new indices that correlate with HI. This study assessed the feasibility of a handheld White Light Scanner (WLS) to obtain 3D measurements and indices of PE deformity.Methods
From April 2015–April 2017, WLS scanning was conducted by orthotists during clinical visits. Included were children with PE up to 18?years. Analysis assessed correlation of a WLS-derived severity index, Hebal-Malas Index (HMI), with physician measured PE Depth (PED), and CT-derived HI.Results
Of 195 participants, 185(94%) patients with PE were scanned and 127(69%) had complete WLS data. For 88 patients undergoing monitoring, HMI correlated with PED (r?=?0.42, p?=?0.004). For 39 patients with pre-operative CT, HMI demonstrated strong correlation with HI (r?=?0.87, p < 0.0001).Conclusions
WLS demonstrated high feasibility of scanning PE. WLS-derived HMI best correlates with HI for patients with severe pectus deformity. Our current data is suggestive that WLS is best applied for severe deformities and yet to be established for milder deformities. Future yearly WLS will provide data on deformity progression and surgical therapy.Level of Evidence
IV.Type of Study
Diagnostic Study. 相似文献2.
Cardiac imaging in the evaluation of patients presenting to the emergency department with chest pain
Conclusions Despite the utility and benefits that each imaging modality has to offer, it is easy to see why there is still no perfect
choice for a noninvasive cardiac imaging modality to assist in the management of chest pain patients. All of the current imaging
techniques have their own significant strengths and weaknesses when compared with other modalities. SPECT and echocardiography
are wellestablished technologies that can directly assess the presence of myocardial ischemia and its functional consequence
on RF; newer and more expensive techniques such as MDCT and CMR can directly assess coronary anatomy and have just started
to be evaluated in the acute chest pain setting. There are no studies that directly compare these technologies, and more data
are clearly needed before the question of whether anatomic imaging versus perfusion/function imaging is the better approach
can be answered. Other comparisons such as relative safety, availability, logistics, and cost-effectiveness between the various
technologies are also lacking.
Of all of the imaging modalities discussed, MCE is the only portable technology. The images do not require expensive software
or other technology for offline processing before interpretation, and any trained cardiologist can read the study at the bedside
or, potentially, over the Internet, providing near-instantaneous results in the acute cardiac setting, where time is of the
essence.
MCE is also relatively cheap compared with other technologies, a potential advantage for payors but not necessarily for payees.
How reimbursement rates and fee structures eventually affect clinical practice is also unknown.
Despite these and other questions that need to be answered before any one technique will be used exclusively, the future of
noninvasive cardiac imaging remains an exciting and ever-changing field. The adaptation of any one of these techniques into
its proper role in the ED Journal of Nuclear Cardiology Wyrick and Wei 753 Volume 13, Number 6;749-55 Cardiac imaging in patients
with chest pain will take considerably more time and effort in terms of research, money, and time-tested clinical experience. 相似文献
3.
Pawan Kumar Dhruva Rao Deborah Clements Michael M. Davies Jared Torkington 《Surgical endoscopy》2007,21(6):1036
We present our comments on the above article. 相似文献
4.
Radiotherapy has been successful in treating localized prostate cancer; however, a subset of patients will experience disease
recurrence. Determination of the recurrence location must be made using pretreatment and posttreatment clinical variables,
imaging, and postradiotherapy biopsy. Patients presumed to have local-only recurrence, optimal clinical risk factors, and
an extended life expectancy may be considered for salvage local treatment. Current options include salvage surgery, cryoablation,
and brachytherapy. Although they are associated with higher morbidity than primary therapy, salvage treatments can be effective
and can still provide patients with a good oncologic and functional outcome. As these modalities continue to improve and patient
selection is optimized, better results will evolve. 相似文献
5.
Moh H Malek Dale E Berger William D Marelich Jared W Coburn Travis W Beck Terry J Housh 《European journal of cardio-thoracic surgery》2006,30(4):637-643
The purpose of this study was to use a meta-analytical technique to examine the efficacy of surgical repair of pectus excavatum on pulmonary function. Studies were retrieved via computerized literature searches, cross-referencing from original and review articles. Inclusion criteria were as follows: (1) reporting quantitative measures of preoperative and postoperative pulmonary function; (2) published in the English language; (3) indexed between January 1960 and September 2005; (4) reporting the duration between which preoperative and postoperative assessments were conducted; and (5) describing the pulmonary assessment procedures. The titles and abstracts of potentially relevant articles were reviewed to determine whether they met the criteria for inclusion. Twelve studies representing 313 pectus excavatum patients met the inclusion criteria and were used for the meta-analysis. Random-effects modeling yielded a mean weighted effect size (ES) for pulmonary function which was statistically nonsignificant (ES=0.08, 95% CI=-0.20 to 0.35; P=0.58). The findings of the present study indicated that surgical repair of pectus excavatum does not significantly improve pulmonary function. These findings, however, may be a result of testing pulmonary function under conditions in which pectus excavatum does not manifest itself. 相似文献
6.
Mary Ann Croft Jared P. McDonald Nivedita V. Nadkarni Ting-Li Lin Paul L. Kaufman 《Experimental eye research》2009,89(6):824-832
The goal was to determine the age-related changes in accommodative movements of the lens and ciliary body in rhesus monkeys. Varying levels of accommodation were stimulated via the Edinger-Westphal (E-W) nucleus in 26 rhesus monkeys, aged 6–27 years, and the refractive changes were measured by coincidence refractometry. Centripetal ciliary process (CP) and lens movements were measured by computerized image analysis of goniovideographic images. Ultrasound biomicroscopy (UBM) at 50 MHz was used to visualize and measure accommodative forward movements of the ciliary body in relation to age, accommodative amplitude, and centripetal CP and lens movements. At ~3 diopters of accommodation, the amount of centripetal lens movement required did not significantly change with age (p = 0.10; n = 18 monkeys); however, the amount of centripetal CP movement required significantly increased with age (p = 0.01; n = 18 monkeys), while the amount of forward ciliary body movement significantly decreased with age (p = 0.007; n = 11 monkeys). In the middle-aged animals (12–16.5 years), a greater amount of centripetal CP movement was required to induce a given level of lens movement and thereby a given level of accommodation (p = 0.01), compared to the young animals (6–10 yrs). Collectively, the data suggests that, with age, the accommodative system may be attempting to compensate for the loss of forward ciliary body movement by increasing the amount of centripetal CP movement. This, in turn, would allow enough zonular relaxation to achieve the magnitude of centripetal lens movement necessary for a given amplitude of accommodation. 相似文献
7.
Quantitative evolutionary design 总被引:2,自引:1,他引:1
Jared Diamond 《The Journal of physiology》2002,542(2):337-345
The field of quantitative evolutionary design uses evolutionary reasoning (in terms of natural selection and ultimate causation) to understand the magnitudes of biological reserve capacities, i.e. excesses of capacities over natural loads. Ratios of capacities to loads, defined as safety factors, fall in the range 1.2-10 for most engineered and biological components, even though engineered safety factors are specified intentionally by humans while biological safety factors arise through natural selection. Familiar examples of engineered safety factors include those of buildings, bridges and elevators (lifts), while biological examples include factors of bones and other structural elements, of enzymes and transporters, and of organ metabolic performances. Safety factors serve to minimize the overlap zone (resulting in performance failure) between the low tail of capacity distributions and the high tail of load distributions. Safety factors increase with coefficients of variation of load and capacity, with capacity deterioration with time, and with cost of failure, and decrease with costs of initial construction, maintenance, operation, and opportunity. Adaptive regulation of many biological systems involves capacity increases with increasing load; several quantitative examples suggest sublinear increases, such that safety factors decrease towards 1.0. Unsolved questions include safety factors of series systems, parallel or branched pathways, elements with multiple functions, enzyme reaction chains, and equilibrium enzymes. The modest sizes of safety factors imply the existence of costs that penalize excess capacities. Those costs are likely to involve wasted energy or space for large or expensive components, but opportunity costs of wasted space at the molecular level for minor components. 相似文献
8.
End-of-life (EOL) and palliative care education in medical school curricula stand at a crossroads. Consensus has emerged that these topics merit systematic instruction throughout medical school training, yet curricula all too often consist of sporadic lectures focused on bioethics instead of clinical skills. The medical student authors identified a deficit in their curriculum, and designed and implemented an EOL curriculum module for their colleagues. In early 2000 the authors surveyed senior medical students about their experiences with EOL and palliative education, identifying deficits in clinical training and recommendations for interventions. They then designed a case-based educational module to teach EOL communication skills to medical students commencing clinical training. Faculty with national and local experience with EOL and palliative care reviewed the curriculum. Twelve of these faculty were oriented to the curriculum and then taught it in pairs to groups of 12 to 16 medical students in 2000 and 2001. The curriculum develops skills, attitudes, and knowledge relevant for communicating bad news and establishing treatment options in the EOL setting by utilizing trigger videos, group discussion, role plays, and case discussions. Approximately 75% of the 86 eligible students attended the module in 2000 and 2001. Feedback has guided the curriculum's refinement by the medical student authors. In addition, a standardized patient exercise, introduced in 2001, allowed students to reinforce the skills learned during the module. 相似文献
9.
Robert F. Hink Wayne H. Fenton Jr. Adolph Pfefferbaum Jared R. Tinklenberg Bert S. Kopell 《Psychophysiology》1978,15(5):466-473
In order to determine the extent to which distraction disrupts performance when attention is divided, the distribution of attention across five auditory input channels was assessed using the N1 component of the human auditory evoked potential. In addition, the possibility that methylphenidate (Ritalin) affects the distribution of attention across input channels was tested. Sixteen subjects performed a tone discrimination task under conditions of focused attention and divided attention, both with and without the presence of stimuli interposed between the points to be attended. The subjects performed in two sessions during which they received either methylphenidate (10 mg) or a placebo in a double-blind design. The results showed that the interposed stimuli were receiving some attention resulting in a disruption of performance. Methylphenidate did not affect the distribution of attention as reflected in the N1 wave. The data are interpreted as showing that: 1) distraction plays a major role in producing performance deficits observed with divided attention; and 2) methylphenidate does not appreciably affect the distribution of attention across input channels. 相似文献
10.
Jared Liu Hsin-Wen Chang Zhi-Ming Huang Mio Nakamura Sahil Sekhon Richard Ahn Priscila Munoz-Sandoval Shrishti Bhattarai Kristen M. Beck Isabelle M. Sanchez Eric Yang Mariela Pauli Sarah T. Arron Wai-Ping Fung-Leung Ernesto Munoz Xuejun Liu Tina Bhutani Jeffrey North Wilson Liao 《The Journal of allergy and clinical immunology》2021,147(6):2370-2380