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There has been limited community engagement in the burgeoning field of genomics research. In the wake of a new discovery of genetic variants that increase the risk of kidney failure and are almost unique to people of African ancestry, community and clinical leaders in Harlem, New York, formed a community board to inform the direction of related research. The board advised all aspects of a study to assess the impact of testing for these genetic variants at primary care sites that serve diverse populations, including explaining genetic risk to participants. By reflecting on the board's experiences, we found that community voices can have tangible impact on research that navigates the controversial intersection of race, ancestry, and genomics by heightening vigilance, fostering clear communication between researchers and the community, and encouraging researchers to cede some control. Our reflections and work provide a strong justification for longitudinal community partnerships in genomics research.

Objectives: The aim of this study was to assess clinical safety and efficacy outcomes of renal denervation executed by an externally delivered, completely noninvasive focused therapeutic ultrasound device., Background: Renal denervation has emerged as a potential treatment approach for resistant hypertension., Methods: Sixty-nine subjects received renal denervation with externally delivered focused ultrasound via the Kona Medical Surround Sound System. This approach was investigated across 3 consecutive studies to optimize targeting, tracking, and dosing. In the third study, treatments were performed in a completely noninvasive way using duplex ultrasound image guidance to target the therapy. Short- and long-term safety and efficacy were evaluated through use of clinical assessments, magnetic resonance imaging scans prior to and 3 and 24 weeks after renal denervation, and, in cases in which a targeting catheter was used to facilitate targeting, fluoroscopic angiography with contrast., Results: All patients tolerated renal denervation using externally delivered focused ultrasound. Office blood pressure (BP) decreased by 24.6 ± 27.6/9.0 ± 15.0 mm Hg (from baseline BP of 180.0 ± 18.5/97.7 ± 13.7 mm Hg) in 69 patients after 6 months and 23.8 ± 24.1/10.3 ± 13.1 mm Hg in 64 patients with complete 1-year follow-up. The response rate (BP decrease >10 mm Hg) was 75% after 6 months and 77% after 1 year. The most common adverse event was post-treatment back pain, which was reported in 32 of 69 patients and resolved within 72 h in most cases. No intervention-related adverse events involving motor or sensory deficits were reported. Renal function was not altered, and vascular safety was established by magnetic resonance imaging (all patients), fluoroscopic angiography (n = 48), and optical coherence tomography (n = 5)., Conclusions: Using externally delivered focused ultrasound and noninvasive duplex ultrasound, image-guided targeting was associated with substantial BP reduction without any major safety signals. Further randomized, sham-controlled trials will be needed to validate this unique approach., (Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Global ischemia in humans or induced experimentally in animals causes selective and delayed neuronal death in pyramidal neurons of the hippocampal CA1. The ovarian hormone estradiol administered before or immediately after insult affords histological protection in experimental models of focal and global ischemia and ameliorates the cognitive deficits associated with ischemic cell death. However, the impact of estradiol on the functional integrity of Schaffer collateral to CA1 (Sch-CA1) pyramidal cell synapses following global ischemia is not clear. Here we show that long term estradiol treatment initiated 14 days prior to global ischemia in ovariectomized female rats acts via the IGF-1 receptor to protect the functional integrity of CA1 neurons. Global ischemia impairs basal synaptic transmission, assessed by the input/output relation at Sch-CA1 synapses, and NMDA receptor (NMDAR)-dependent long term potentiation (LTP), assessed at 3 days after surgery. Presynaptic function, assessed by fiber volley and paired pulse facilitation, is unchanged. To our knowledge, our results are the first to demonstrate that estradiol at near physiological concentrations enhances basal excitatory synaptic transmission and ameliorates deficits in LTP at synapses onto CA1 neurons in a clinically-relevant model of global ischemia. Estradiol-induced rescue of LTP requires the IGF-1 receptor, but not the classical estrogen receptors (ER)-α or β. These findings support a model whereby estradiol acts via the IGF-1 receptor to maintain the functional integrity of hippocampal CA1 synapses in the face of global ischemia. This article is part of a Special Issue entitled SI: Brain and Memory., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: To present our experiences in initial clinical evaluation of a novel mechatronic system for in-bore guidance of needles to the prostate for MRI-guided prostate interventions in 10 patients. We report accuracy of this device in the context of focal laser ablation therapy for localized prostate cancer., Methods: An MRI-compatible needle guidance device was developed for transperineal prostate interventions. Ten patients underwent MRI-guided focal laser ablation therapy with device-mediated laser fiber delivery. We recorded needle guidance error and needle delivery time., Results: A total of 37 needle insertions were evaluated. Median needle guidance error was 3.5 mm (interquartile range, 2.1-5.4 mm), and median needle delivery time was 9 min (interquartile range, 6.5-12 min)., Conclusion: This system provides a reliable method of accurately aligning needle guides for in-bore transperineal needle delivery to the prostate., (© 2014 Wiley Periodicals, Inc.)

Purpose: To describe the 12-month safety and efficacy outcomes of 16 or 24 Gy radiation using low-voltage x-ray irradiation in conjunction with intravitreal ranibizumab for neovascular age-related macular degeneration (AMD)., Design: Prospective, phase I, open-label, nonrandomized uncontrolled safety study., Methods: setting: Institutional. study population: Neovascular AMD patients. intervention: One x-ray irradiation treatment at 16 or 24 Gy was administered externally through 3 locations in the inferior pars plana. After 2 initial monthly loading doses of ranibizumab, subsequent ranibizumab was administered according to predetermined criteria. main outcome measures: Visual acuity, number of ranibizumab injections, safety and efficacy metrics at 12 months., Results: Forty-seven eyes of 47 patients were enrolled and completed 12 months of follow-up: 16 Gy (n = 28) and 24 Gy (n = 19). There was no evidence of radiation retinopathy, optic neuropathy, or cataract. The mean visual acuity improved in both groups: +8.4 ± 11.9 letters and +7.8 ± 12 letters for 16 and 24 Gy, respectively. In both groups, 100% of subjects lost <15 letters, with 76% and 79% gaining ≥0 letters in the 16 Gy and 24 Gy groups, respectively. Patients received a mean of 1.0 additional injection over 12 months. The mean change in optical coherence tomography central subfield thickness from baseline to month 12 was -107 and -87 μm for the 16 Gy and 24 Gy groups, respectively., Conclusion: One treatment of 16 or 24 Gy low-voltage x-ray therapy with as-needed ranibizumab appears safe in subjects with neovascular AMD at 12 months. An overall improvement in visual acuity was observed. No radiation-related adverse effects were reported., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background and Objective: To describe 'radiation-first' combination treatment with a non-invasive, low-voltage x-ray irradiation system followed by as needed ranibizumab for neovascular age-related macular degeneration (AMD)., Study Design and Methods: Phase I study of non-invasive, low-voltage 16 Gy x-ray irradiation delivered in three beams via the inferior pars plana in patients with active neovascular AMD. Ranibizumab was administered as needed per protocol. Patients were followed monthly for safety and efficacy over 12 months., Results: 13 patients were enrolled and completed 12 months follow-up. Safety was good with no serious ocular/non-ocular adverse events or radiation-related ocular complications. 11 patients lost <15 Early Treatment of Diabetic Retinopathy Study (ETDRS) letters, seven gained ≥0 ETDRS letters and 0 gained ≥15 ETDRS letters. Patients received a total of 31 subsequent ranibizumab injections (of possible 156) over the 12 months following x-ray irradiation. Mean time to first injection was 3.9 months. One patient received no ranibizumab injections, three patients received one injection, four patients received two injections, and five patients received three or more injections., Conclusions: After 12 months, non-invasive, low-voltage x-ray irradiation with as needed ranibizumab rescue therapy demonstrated good safety with a visual acuity stabilising effect and reduction in retinal thickness in patients with neovascular AMD.

Objective. To determine the dose response and toxicity threshold of micro-collimated X-rays delivered to porcine maculae by a stereotactic radiosurgical system after 270 days. Methods. Twelve eyes of six Yucatan mini-swine were randomized to receive up to 90 Gy to the retina, using an office-based trans-pars plana delivery system. To determine the safety profile of this radiation delivery, ophthalmic examination, fundus photography, fluorescein angiography (FA), and spectral domain optical coherence tomography (SD-OCT) were obtained at multiple time points up to 270 days post treatment. Results. No abnormalities were noted on external examination. Cataracts were noted in 4 of 12 eyes. Dose and time-dependent changes were noted on fundus examination, FA, ICG and SD-OCT. No significant abnormalities were seen in the control, 16 Gy or 24 Gy groups using any modality. Histopathology revealed a dose response effect with no discernable lesions in the 16 Gy group. Conclusion. The X-ray delivery system precisely targets the porcine retina in vivo with little effect on surrounding structures. No ophthalmic or intracranial adverse effects were noted at clinically relevant doses at 270 days following radiation delivery.

Background and Objective: To describe the 6-month safety and preliminary efficacy outcomes of the use of 24-Gy radiation with intravitreal ranibizumab for patients with neovascular age-related macular degeneration (AMD)., Patients and Methods: A single treatment of a non-invasive, externally delivered low-voltage x-ray irradiation at a dose of 24 Gy was administered in one session through three locations in the inferior pars plana in a consecutive series of patients with neo-vascular AMD (treatment naïve and previously treated). Optical coherence tomography (OCT) and Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity examinations were performed at 1 week, 1 month, and monthly thereafter with quarterly fluorescein angiography., Results: Nineteen patients completed 6 months of follow-up. There was no evidence of radiation retinopathy, optic neuropathy, or cataract. The mean baseline ETDRS score was 38.3 ± 19.5 letters. At 6 months, the corresponding ETDRS score was 44.7 ± 16.8 letters. At 6 months, the mean change in visual acuity was 6.4 ± 9.8 ETDRS letters. Patients received an average of 0.4 additional ranibizumab injections following the initial two mandated injections., Conclusion: A single treatment of external 24-Gy low-voltage x-ray therapy in conjunction with ranibizumab demonstrated an overall improvement in visual acuity in patients with neovascular AMD at 6 months, with no radiation-related adverse effects., (Copyright 2012, SLACK Incorporated.)

Background and Objective: To describe the effect of a "radiation-first" combination treatment strategy for neovascular age-related macular degeneration (AMD) with ranibizumab rescue therapy., Patients and Methods: Non-invasive, externally delivered low-voltage x-ray irradiation at a dose of 16 Gy was given in a single session through three locations in the inferior pars plana in a consecutive series of patients with neovascular AMD. Ranibizumab was administered according to prospectively determined criteria., Results: Thirteen patients completed a 6-month follow-up. All patients lost 15 or fewer ETDRS letters, 7 gained 0 or more ETDRS letters, and 0 gained more than 15 ETDRS letters. Patients received a total of 15 ranibizumab injections following x-ray irradiation at baseline. Two patients received no ranibizumab injections, seven patients received 1 injection, and four patients received 2 injections., Conclusion: Low-voltage x-ray treatment followed by ranibizumab rescue demonstrates an independent visual acuity stabilizing effect for patients with wet AMD., (Copyright 2011, SLACK Incorporated.)

Background and Objective: To describe the 6-month safety and preliminary efficacy outcomes of the use of 16-Gy radiation with intravitreal ranibizumab for patients with neovascular age-related macular degeneration (AMD)., Patients and Methods: A single treatment of a non-invasive, externally delivered low-voltage 16-Gy x-ray irradiation was administered in one session through three locations in the inferior pars plana. Optical coherence tomography (OCT) and Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity (VA) examinations were performed at 1 week, 1 month, and monthly thereafter, with quarterly fluorescein angiography (FA). After the two initial ranibizumab injections, subsequent injections were administered according to the following criteria: VA decline of 10 ETDRS letters compared with baseline, increase of 100-μm central foveal thickness on OCT compared with baseline, the development of new submacular hemorrhage, and the development of a new area of classic choroidal neovascularization on FA., Results: Twenty-six patients completed a 6-month follow-up. There was no evidence of radiation retinopathy, optic neuropathy, or cataract. The mean baseline ETDRS score was 46.6 letters (range: 5 to 80; standard deviation [SD]: 21.5). At 6 months, the corresponding ETDRS score was 55.6 letters (range: 25 to 80; SD: 18.9) and the mean change in VA was 9.5 ETDRS letters (SD: 10.3). On responder analysis, 96% lost 15 or fewer ETDRS letters, 81% gained 0 or more ETDRS letters, and 50% gained 15 or more ETDRS letters. Patients received a total of 13 ranibizumab injections following two initial injections. At 6 months, patients received an average of 0.5 additional injections following the initial two mandated injections., Conclusion: A single treatment of externally applied, non-invasive 16-Gy low-voltage x-ray therapy in conjunction with ranibizumab demonstrated an overall improvement of VA in patients with neovascular AMD at 6 months with no radiation-related adverse effects., (Copyright 2011, SLACK Incorporated.)

Objective: To investigate the effects of a novel stereotactic radiosurgical system for pars plana delivery of microcollimated x-rays to the retina and determine the retinal radiological dose response and toxicity threshold in a pig model., Methods: The x-rays were delivered through the pars plana to the maculae of Yucatan miniswine to verify the targeting and safety of a cornea-scleral, stabilized, office-based delivery system. Twelve eyes were randomized to receive 0, 16, 24, 42, 60, or 90 Gy in a single dose to the retina. Eye examinations, fundus photography, fluorescein angiography, and spectral-domain optical coherence tomography were obtained at days 7, 30, 60, and 90. Indocyanine green angiography was done at day 90., Results: Through day 90 interim analysis, no abnormalities of external structures were noted. A small cortical lens opacity was noted in the 60-Gy group. Fundus evaluation revealed no abnormalities at 16 or 24 Gy. Beginning at day 30, circular pale retinal lesions with sharp margins were noted in the maculae of the eyes that received 42, 60, and 90 Gy. Higher-dose lesions showed late staining on fluorescein angiography, choroidal hypoperfusion on indocyanine green angiography, and defined photoreceptor loss and retinal thinning on spectral-domain optical coherence tomography., Conclusion: Transscleral stereotactic radiation dosing of porcine eyes demonstrates no apparent clinical abnormalities in doses less than 24 Gy. Doses of 42 Gy or higher led to focal choroidal and retinal damage within the target area., Clinical Relevance: Radiation can induce small-blood vessel closure and thereby has therapeutic potential in neovascular diseases such as age-related macular degeneration.

The IRay stereotactic low-voltage x-ray irradiation treatment system for age-related macular degeneration consists of a low voltage x-ray tube, an eye tracking system, a robotically controlled delivery system, a coupling device to facilitate tracking and stabilisation, a graphical user interface and gating software. Low-voltage x-rays are delivered in a series of three spots to the macula in a non-invasive manner through the inferior pars plana. These beams are designed to overlap on the centre of the macula. Each beam delivers one-third of the total dose, such that the total macula dose is three times an individual beam's dose. The device is designed to run off standard domestic electrical power, and no special shielding is necessary for the room. This system has been validated in Monte Carlo simulations, human cadaver eye studies, pre-clinical animal studies and in a phase I clinical trial.

Age-related macular degeneration (AMD), a leading cause of blindness in the United States, is a neovascular disease that may be controlled with radiation therapy. Early patient outcomes of external beam radiotherapy, however, have been mixed. Recently, a novel multimodality treatment was developed, comprising external beam radiotherapy and concomitant treatment with a vascular endothelial growth factor inhibitor. The radiotherapy arm is performed by stereotactic radiosurgery, delivering a 16 Gy dose in the macula (clinical target volume, CTV) using three external low-energy x-ray fields while adequately sparing normal tissues. The purpose of our study was to test the sensitivity of the delivery of the prescribed dose in the CTV using this technique and of the adequate sparing of normal tissues to all plausible variations in the position and gaze angle of the eye. Using Monte Carlo simulations of a 16 Gy treatment, we varied the gaze angle by ±5° in the polar and azimuthal directions, the linear displacement of the eye ±1 mm in all orthogonal directions, and observed the union of the three fields on the posterior wall of spheres concentric with the eye that had diameters between 20 and 28 mm. In all cases, the dose in the CTV fluctuated <6%, the maximum dose in the sclera was <20 Gy, the dose in the optic disc, optic nerve, lens and cornea were <0.7 Gy and the three-field junction was adequately preserved. The results of this study provide strong evidence that for plausible variations in the position of the eye during treatment, either by the setup error or intrafraction motion, the prescribed dose will be delivered to the CTV and the dose in structures at risk will be kept far below tolerance doses.

Background: SLC25A12, a susceptibility gene for autism spectrum disorders that is mutated in a neurodevelopmental syndrome, encodes a mitochondrial aspartate-glutamate carrier (aspartate-glutamate carrier isoform 1 [AGC1]). AGC1 is an important component of the malate/aspartate shuttle, a crucial system supporting oxidative phosphorylation and adenosine triphosphate production., Methods: We characterized mice with a disruption of the Slc25a12 gene, followed by confirmatory in vitro studies., Results: Slc25a12-knockout mice, which showed no AGC1 by immunoblotting, were born normally but displayed delayed development and died around 3 weeks after birth. In postnatal day 13 to 14 knockout brains, the brains were smaller with no obvious alteration in gross structure. However, we found a reduction in myelin basic protein (MBP)-positive fibers, consistent with a previous report. Furthermore, the neocortex of knockout mice contained abnormal neurofilamentous accumulations in neurons, suggesting defective axonal transport and/or neurodegeneration. Slice cultures prepared from knockout mice also showed a myelination defect, and reduction of Slc25a12 in rat primary oligodendrocytes led to a cell-autonomous reduction in MBP expression. Myelin deficits in slice cultures from knockout mice could be reversed by administration of pyruvate, indicating that reduction in AGC1 activity leads to reduced production of aspartate/N-acetylaspartate and/or alterations in the dihydronicotinamide adenine dinucleotide/nicotinamide adenine dinucleotide(+) ratio, resulting in myelin defects., Conclusions: Our data implicate AGC1 activity in myelination and in neuronal structure and indicate that while loss of AGC1 leads to hypomyelination and neuronal changes, subtle alterations in AGC1 expression could affect brain development, contributing to increased autism susceptibility., (Copyright 2010 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)

Purpose: Validation of the targeting and dose delivery of the IRay low voltage age-related macular degeneration treatment system., Methods: Ten human cadaver eyes were obtained for this study and mounted in the IRay system. Using gel and vacuum, an I-Guide immobilization device was coupled to the eyes and radiochromic film was affixed to the posterior aspect of the globes. Three narrow x-ray beams were delivered through the pars plana to overlap on the predicted nominal fovea. A needle was placed through the center of the film's beam spot and into the eye to register the film and the inner retina. The process was performed three times for each of the ten eyes (30 simulated treatments; 90 individual beams). The globes were dissected to assess the targeting accuracy by measuring the distances from the needles to the fovea. The dose to the fovea was calculated from the radiochromic film., Results: X-ray targeting on the retina averaged 0.6 +/- 0.4 mm from the fovea. Repeated treatments on the same eye showed a reproducibility of 0.4 +/- 0.4 mm. The optic nerve was safely avoided, with the 90% isodose edge of the beam spot between 0.4 and 2.6 mm from the edge of the optic disk. Measured dose matched that prescribed., Conclusions: This study provides confidence that the IRay, with an average accuracy of 0.6 mm and a precision of 0.4 mm, can reliably treat most AMD lesions centered on the fovea. With the exception of motion, all sources of error are included.

Age-related macular degeneration (AMD) is a leading cause for vision loss for people over the age of 65 in the United States and a major health problem worldwide. Research for new treatments of the wet form of the disease using kilovoltage stereotactic radiosurgery is currently underway at Oraya Therapeutics, Inc. In the present study, the authors extend their previous computational stylized model of a single treated eye [Med. Phys. 35, 5151-5160 (2008)] to include full NURBS-based reference head phantoms of the adult male and female using anatomical data from ICRP Publication 89. The treatment was subsequently modeled in MCNPX 2.5 using a 1 x 1 x 1 mm3 voxelized version of the NURBS models. These models incorporated several organs of interest including the brain, thyroid, salivary glands, cranium, mandible, and cervical vertebrae. A higher resolution eye section at 0.5 x 0.5 x 0.5 mm3 voxel resolution was extracted from the head phantoms to model smaller eye structures including the macula target, cornea, lens, vitreous humor, sclera/retina layer, and optic nerve. Due to lack of literature data on optic nerve pathways, a CT imaging study was undertaken to quantify the anatomical position of the optic nerve. The average absorbed doses to the organs of interest were below generally accepted thresholds for radiation safety. The estimated effective dose was 0.28 mSv which is comparable to diagnostic procedures such as a head radiograph and a factor of 10 lower than a head CT scan.

We present a 2-day water maze protocol that addresses some of potential confounds present in the water maze when using the aged subjects typical of studies of neurodegenerative disorders, such as Alzheimer's disease. This protocol is based on an initial series of training trials with a visible platform, followed by a memory test with a hidden platform 24h later. We validated this procedure using aged (15-18m) mice expressing three Alzheimer's disease-related transgenes, PS1(M146 V), APP(Swe), and tau(P301L). We also tested these triple transgenic mice (3xTG) and age and sex-matched wild-type (WT) in a behavioral battery consisting of tests of motor coordination (balance beam), spatial memory (object displacement task) visual acuity (novel object recognition task) and locomotor activity (open field). 3xTG mice had significantly longer escape latencies in the memory trial of the 2-day water maze test than WT and than their own baseline performance in the last visible platform trial. In addition, this protocol had improved sensitivity compared to a typical probe trial, since no significant differences between genotypes were evident in a probe trial conducted 24h after the final training trial. The 2-day procedure also resulted in good reliability between cohorts, and controlled for non-cognitive factors that can confound water maze assessments of memory, such as the significantly lower locomotor activity evident in the 3xTG mice. A further benefit of this method is that large numbers of animals can be tested in a short time.

Age-related macular degeneration (ARMD) is a major health problem worldwide. Advanced ARMD, which ultimately leads to profound vision loss, has dry and wet forms, which account for 20% and 80% of cases involving severe vision loss, respectively. A new device and approach for radiation treatment of ARMD has been recently developed by Oraya Therapeutics, Inc. (Newark, CA). The goal of the present study is to provide a initial dosimetry characterization of the proposed radiotherapy treatment via Monte Carlo radiation transport simulation. A 3D eye model including cornea, anterior chamber, lens, orbit, fat, sclera, choroid, retina, vitreous, macula, and optic nerve was carefully designed. The eye model was imported into the MCNPX2.5 Monte Carlo code and radiation transport simulations were undertaken to obtain absorbed doses and dose volume histograms (DVH) to targeted and nontargeted structures within the eye. Three different studies were undertaken to investigate (1) available beam angles that maximized the dose to the macula target tissue, simultaneously minimizing dose to normal tissues, (2) the energy dependency of the DVH for different x-ray energies (80, 100, and 120 kVp), and (3) the optimal focal spot size among options of 0.0, 0.4, 1.0, and 5.5 mm. All results were scaled to give 8 Gy to the macula volume, which is the current treatment requirement. Eight beam treatment angles are currently under investigation. In all eight beam angles, the source-to-target distance is 13 cm, and the polar angle of entry is 300 from the geometric axis of the eye. The azimuthal angle changes in eight increments of 45 degrees in a clockwise fashion, such that an azimuthal angle of 0 degreee corresponds to the 12 o'clock position when viewing the treated eye. Based on considerations of nontarget tissue avoidance, as well as facial-anatomical restrictions on beam delivery, treatment azimuthal angles between 135 degrees and 225 degrees would be available for this treatment system (i.e., directly upward and entering the eye from below). At beam directions approaching 225 degrees and higher, some dose contribution to the optic nerve would result under the assumption that the optic nerve is tilted cranially above the geometric axis in a given patient, a feature not typically seen in past studies. A total treatment dose of 24 Gy would be delivered in three 8 Gy treatments at these selected azimuthal angles. Dose coefficients, defined as the macula radiation absorbed dose per unit air kerma in units of Gy/Gy, were 16% higher for 120 kVp x-ray beams in comparison to those at 80 kVp, thus requiring only 86% of the integrated tube current (mAs) for equivalent dose delivery. When 0.0, 0.4, and 1.0 mm focal spot sizes were used, the dose profiles in the macula are very similar and relatively uniform, whereas a 5.5 mm focal spot size produced a more nonuniform dose profile. The results of this study dem onstrate the therapeutic promise of this device and provide important information for further design and clinical implementation for radiotherapy treatments for ARMD.

Background: Few studies have been designed to assess the performance of surgical staplers. In this study, we analyzed the effect of staple height, buttressing, and overlapping of staple lines on staple line failure., Methods: Staple lines created on fresh porcine small bowel segments ex vivo were tested for leak pressure by insufflating air into the bowel under water and recording pressure at failure. Three separate experiments were done and included staple height (white, 2.5 mm, n = 16; blue, 3.5 mm, n = 16; green, 4.1 mm, n = 16; one half of them buttressed); the absence (n = 12) or presence (n = 12) of an overlap in 3.5-mm staple lines; and the absence (n = 14) or presence (n = 11) of buttresses in 3.5-mm overlapping staple lines. Data are reported in median values and ranges; nonparametric tests were used for data analysis., Results: In the porcine small bowel, leak pressure was related to staple height; green loads had the worst profile (35 mm Hg, range 19-105) compared with the blue (79 mm Hg, range 9-177), and white (108 mm Hg, range 28-280) loads (P = .006). Buttressing uniformly improved leak pressure for all staple loads (P <.0001). No significant difference was found between lines with overlapping (59 mm Hg, range 32-121) and those without (42 mm Hg, range 22-75; P = .162). Buttressing also improved the leak pressure of overlapping staple lines from 65 mm Hg (range 47-121) to 93 mm Hg (range 75-187; P = .0014)., Conclusion: Great variability was found in the leak pressures among the different applications of the same stapler. Staple height is an important determinant of leak pressure. The presence of an overlap did not affect leak pressure; in fact, a trend toward improvement was seen with overlapping staple lines. Buttressing improved all types of staple lines.

The innovation process is often more important than the original idea, particularly when the ultimate goal is to improve patient care through technologically advanced products. Many physicians have great ideas; unfortunately, many of these great ideas are never translated to patient care improvements because of a misunderstanding of "the next step." In many cases, the next step is a step backward to understand the real clinical problem: "the clinical need." With the clinical need in hand, the most efficient path to a product for improved patient care can then be derived. Often, the most efficient pathway involves an appreciation of many issues, including intellectual property, regulatory pathways, finance, and clinical trial strategies. The integration of these issues underlies innovation in biomedical technology.

Objective: To describe the field of surgical innovation from a historical perspective, applying new findings from research in technology innovation., Background: While surgical innovation has a rich tradition, as a field of study it is embryonic. Only a handful of academic centers of surgical innovation exist, all of which have arisen within the last 5 years. To this point, the field has not been well defined, nor have future options to promote surgical innovation been thoroughly explored. It is clear that surgical innovation is fundamental to surgical progress and has significant health policy implications. A process of systematically evaluating and promoting innovation in surgery may be critical in the evolving practice of medicine., Methods: A review of the academic literature in technology innovation was undertaken. Articles and books were identified through technical, medical, and business sources. Luminaries in surgical innovation were interviewed to develop further relevance to surgical history. The concepts in technology innovation were then applied to innovation in surgery, using the historical example of surgical endoscopy as a representative area, which encompasses millennia of learning and spans multiple specialties of care., Results: The history of surgery is comprised largely of individual, widely respected surgeon innovators. While respecting individual accomplishments, surgeons as a group have at times hindered critical innovation to the detriment of our profession and patients. As a clinical discipline, surgery relies on a tradition of research and attracting the brightest young minds. Innovation in surgery to date has been impressive, but inconsistently supported., Conclusion: A body of knowledge on technology innovation has been developed over the last decade but has largely not been applied to surgery. New surgical innovation centers are working to define the field and identify critical aspects of surgical innovation promotion. It is our responsibility as a profession to work to understand innovation in surgery, discover, translate, and commercialize advances to address major clinical problems, and to support the future of our profession consistently and rationally.

Current surgical care and technology has evolved over the centuries from the interplay between creative surgeons and new technologies. As both fields become more specialized, that interplay is threatened. A 2-year educational fellowship is described which teaches both the process and the discipline of medical/surgical device innovation. Multi-disciplinary teams (surgeons, engineers, business grads) are assembled to educate a generation of translators, who can bridge the gap between scientific and technologic advances and the needs of the physician and the patient.

Primary Objective: To examine the validity of Maryland Hospital Discharge (MHD) data for identifying and characterizing traumatic brain injury (TBI)-related hospitalizations., Methods: All TBI-related hospitalizations in 1999 were identified using MHD and Maryland Trauma Registry (MTR) data. In addition, a sample of records were abstracted to compare agreement between MHD and chart data., Results: The MHD file identified fewer TBI cases (61%) compared to the MTR (95%). Overall, TBI-related hospitalization rates based on MHD were significantly fewer (95; 95% CI 92, 98) vs MHD and MTR (144; 95% CI 140, 147). There was good agreement between the MHD and chart data regarding skull fractures or intracranial lesions (kappa = 0.73 and 0.83, respectively), but poor agreement for neurologic abnormalities or amnesia. The MHD significantly underestimated TBI severity., Conclusions: TBI cases, especially mild ones, were under-reported by MHD data. MHD data are better at detecting anatomic injuries compared to TBI symptoms and sequella.

Photodynamic therapy of solid organs requires sufficient PDT dose throughout the target tissue while minimizing the dose to proximal normal structures. This requires treatment planning for position and power of the multiple delivery channels, complemented by on-line monitoring during treatment of light delivery, drug concentration and oxygen levels. We describe our experience in implementing this approach in Phase I/II clinical trials of the Pd-bacteriophephorbide photosensitizer TOOKAD (WST09)-mediated PDT of recurrent prostate cancer following radiation failure. We present several techniques for delivery and monitoring of photodynamic therapy, including beam splitters for light delivery to multiple delivery fibers, multi-channel light dosimetry devices for monitoring the fluence rate in the prostate and surrounding organs, methods of measuring the tissue optical properties in situ, and optical spectroscopy for monitoring drug pharmacokinetics of TOOKAD in whole blood samples and in situ in the prostate. Since TOOKAD is a vascular-targeted agent, the design and implementation of the techniques are different than for cellular-targeted agents. Further development of these delivery and monitoring techniques will permit full on-line monitoring of the treatment that will enable real-time, patient-specific and optimized delivery of PDT.

Background: This study aimed to examine the validity of using Maryland hospital discharge data to characterize injuries sustained by trauma patients., Methods: Maryland hospital discharge and Maryland trauma registry data for 1999 were merged, and the extent of agreement regarding the presence and severity of injuries sustained was evaluated., Results: The mean Injury Severity Score was 8.4 according to the Maryland hospital discharge data and 10 according to the Maryland trauma registry data (p < 0.0001). The Maryland hospital discharge data identified 95% or more of all moderate to severe injuries (Abbreviated Injury Score, > or =2) for all body regions except the head. There was substantial agreement between the two data sets for mechanism of injury (weighted kappa, 0.62), the number of preexisting conditions present (weighted kappa, 0.45) and final disposition (weighted kappa, 0.78)., Conclusions: The Maryland hospital discharge data are a valid source for documenting the nature and severity of injuries sustained by trauma patients, except for those with a relatively minor head injury.

Hypothesis: The diagnostic yield of chest radiography; computed tomography (CT) of the chest, abdomen, and pelvis; and CT or magnetic resonance imaging of the brain in the initial evaluation of melanoma with metastasis to sentinel lymph nodes may not identify systemic disease., Design: Retrospective analysis., Setting: Tertiary care referral center., Patients: Of 1183 patients identified from a database of individuals who underwent selective sentinel lymphadenectomy for primary melanoma (Breslow thickness, 0.2-30 mm), we studied 185 with at least 1 sentinel lymph node positive for metastatic melanoma (Breslow thickness, 0.8-14.5 mm)., Interventions: Chest radiography; CT of the chest, abdomen, and pelvis; and CT or magnetic resonance imaging of the brain after selective sentinel lymphadenectomy with positive sentinel lymph nodes. The medical records of the 185 patients were systematically reviewed by 4 physician reviewers, and data were extracted primarily from pathology and radiology reports. When medical records were unavailable, information was taken from formal clinic and inpatient progress notes., Main Outcome Measure: Diagnostic yield of imaging studies., Results: The results of 0.5% of the imaging studies were positive for metastatic disease, 86% were negative, and 14% were indeterminate. Indeterminate results were confirmed to be negative by additional studies ranging from repeated imaging to invasive procedures, including thoracotomy and brain biopsy. The yields are as follows: chest radiography, 0%; chest CT, 0.7%; abdominal and pelvic CT, 0.7%; brain CT, 0%; and brain magnetic resonance imaging, 0%. Only 1 patient (0.5%) had detectable metastatic disease, and he had symptoms of systemic disease at the time of imaging., Conclusions: Computed tomography of the chest, abdomen and pelvis, and brain rarely reveals systemic metastasis at the time of selective sentinel lymphadenectomy. Routine imaging of asymptomatic patients at the time of selective sentinel lymphadenectomy is not indicated.

Purpose: Interstitial microwave thermal therapy is experimental treatment for prostate cancer with the goal of curing disease, while causing fewer complications than standard treatment options. We present a method for delivering interstitial microwave thermal therapy using microwave radiating helical antennae inserted percutaneously under transrectal ultrasound guidance. We report the results of a trial of this method in 25 patients in whom primary external beam radiation therapy had previously failed. This patient group currently has limited curative options that are associated with a high complication rate. However, these recurrent tumors often remain localized to the prostate, and so they may be amenable to localized therapy., Materials and Methods: Patients with proved prostatic adenocarcinoma were candidates for treatment when prostate specific antigen (PSA) was 15 ng./ml. or less and prostate volume was 50 cc. or less. Followup included PSA measurement, digital rectal examination, urinalysis, and documentation of adverse events at 4, 8, 12 and 24 weeks. Sextant biopsy was performed at week 24. The procedure involved the insertion of 5 antennae percutaneously through a modified brachytherapy template. The antenna arrangement was determined based on computer simulated predictions of temperature throughout the prostate. The prostate was dissected away from the rectum by an injection of sterile saline to provide a thermal barrier that protected the rectum from thermal damage. Temperatures were monitored using interstitial mapping thermistor probes that were also inserted through the template. A minimum peripheral target temperature of 55C but less than 70C was maintained for 15 to 20 minutes, while the urethra, rectum and hydrodissection space remained below 42C. The urethra and rectum were actively cooled in addition to hydrodissection., Results: Peripheral target temperatures of 55C were achieved. The urethra and rectum remained at a safe temperature. The procedure, including setup and treatment, required approximately 2.5 hours of operating room time. At 24 weeks the PSA nadir was 0.5 ng./ml. or less in 52% of patients and 0.51 to 4 ng./ml. was achieved in an additional 40%. The negative biopsy rate at 24 weeks was 64%, assuming that 3 patients lost to followup would have had positive results. No major complications were observed and in most cases minor complications resolved within 3 months., Conclusions: Interstitial microwave thermal therapy for prostate cancer was developed to heat the prostate safely to a cytotoxic temperature. Experience with 25 patients in whom external beam radiation therapy for prostate cancer had failed indicates that the treatment is safe. Although our series indicates that this therapy may be effective, further studies and longer followup are required in larger patient groups to confirm the potential role of this therapy as an option for recurrent and primary prostate cancer.

Purpose: Incidentally detected small renal tumors appear to grow slowly and be localized to the kidney. Minimally invasive therapies are being investigated as alternatives to standard surgical techniques. Radiofrequency ablation has been reported for the treatment of small renal cell carcinomas. We developed a radiofrequency technique and established its efficacy and safety in a large animal model., Methods and Methods: A total of 22 lesions were created in normal kidneys of 7 pigs. Radiofrequency energy was administered during open exposure of the kidneys or percutaneously under ultrasound guidance. Lesion development was monitored with gray-scale and power Doppler ultrasound. To avoid heating surrounding tissues new hydro-dissection and gas-dissection techniques were developed. Lesion sizes and characteristics were assessed by ultrasound and pathological examination., Results: No complications were observed due to probe insertion and removal. Perirenal structures were thermally damaged before the development and application of the dissection techniques. Lesion size was accurately predicted by gray-scale ultrasound on day 7. Loss of perfusion in the ablated volume was confirmed by power Doppler ultrasound. Lesions were wedge-shaped, presumably due to the effects of heating on segmental blood flow distribution. Pathological examination revealed changes consistent with thermal injury and ischemic type infarction., Conclusions: Radiofrequency thermal therapy is an effective and efficient method for ablating normal renal tissue in the pig. It may be applied percutaneously under ultrasound guidance with minimal complications provided that vital adjacent structures are protected from thermal damage. Further studies are required in humans before adopting this technique as definitive treatment for small renal cell carcinoma.

Interstitial microwave therapy is an experimental treatment for prostate cancer. The objective of this work was to measure the power deposition (specific absorption rate, SAR) patterns of helical microwave antennae both individually and in array patterns that would be useful for clinical treatment protocols. Commercial helical antenna 3D SAR patterns were measured in muscle equivalent phantoms using a thermographic technique. Two array patterns were tested: a 'square' and a 'crescent' array, both surrounding the urethra. To assess the feasibility of pre-treatment planning, the measured SAR patterns were input to a treatment planning computer simulation program based on a series of trans-rectal ultrasound images from a prostate cancer patient. The simulation solved the Pennes linear bioheat heat transfer equation in prostate tissue, with the aim of achieving a target of 55 degrees C at the prostate periphery while not allowing normal surrounding tissues (bladder, urethra, rectum) to rise above 42 C. These criteria could not be met with the square array but they could be met with the crescent array, provided that the prostate was first dissected away from the rectum. This can be done with a procedure such as 'hydrodissection', where sterile saline is injected to separate the prostate and rectum. The results of these SAR measurements and heat transfer simulations indicate that arrays of helical antennae could be used for safe and effective thermal therapy for prostate cancer.

This study examined the artefact induced in temperature measurements made with thermocouples and Luxtron fluoroptic probes in the presence of infrared radiation. Localized heating was created using a continuous-wave, 810 nm diode laser system emitting 2.0 W from a cylindrical diffusing optical fibre, in air, water and an agar-albumin phantom. The temperature was measured every 1.0 s for 10 to 150 s, with both a thermocouple and a Luxtron fluoroptic probe at distances of 2, 3, 4, 5, 6 and 7 mm from the cylindrical diffusing tip. In all cases, the fluoroptic probe recorded a higher temperature than the thermocouple during laser irradiation. The difference in measured temperatures between the Luxtron probe and the thermocouple ranged from 1.6 degrees C to 18.8 degrees C in air, from 0.3 degrees C to 10.2 degrees C in water, and from 1.4 degrees C to 10.1 degrees C in phantom, depending on the distance of the probe from the laser source. The results suggest that in the presence of laser irradiation, self-heating of the Luxtron probe induces a significant artefact in temperature measurements at distances less than 4 mm from the source fibre. As a result, fluoroptic probes may not be suitable for monitoring tissue temperature for treatments when laser irradiation is present if sensors are located close to the fibre tip (<4 mm).

The risk of infection after rape is believed to be low. The use of presumptive treatment is, therefore, controversial. Some experts recommend treatment of all patients, and others suggest treatment if the doctor suspects infection, if the patient requests it, if follow-up examination of the victim cannot be ensured, or if the assailant has a known infection. No regimen will cover all possible pathogens. The Centers for Disease Control's empiric regimen for victims of sexual assault is effective against gonorrhea, chlamydia, and, most likely, syphilis. We present a case of incubating syphilis following rape, that did not respond to ceftriaxone.

Balloon-catheter dilation of arterial stenoses and/or occlusions has been found to be helpful when used both as an adjunct to arterial surgery and as definitive treatment. Used preoperatively, it enables the extent of surgery to be limited and may improve the patient's general condition and ability to undergo surgery; such is seen when renal or mesenteric vessels are dilated preoperatively. During surgery, it can be used to augment the surgery, particularly in an area that is difficult to expose or out of the operative field. Postoperatively, it is often useful in maintaining patency of a graft or its inflow and outflow tract. Judicious use of this modality can enhance arterial surgery and improve results.

A high incidence of gonadal tumors has been demonstrated in patients with gonadal dysgenesis in the presence of Y chromosome material. A unilateral, microscopic gonadoblastoma was found in the dysgenetic gonad of a ten-year-old, phenotypic female, with Turner stigmata and chromosome mosaicisms of three cell populations 45,X/46,X,+mar,/47,X,+mar,+mar. It is often impossible to determine by cytogenetic analysis if the marker chromosome has derived from the X or Y chromosome. The origin of these marker chromosomes was elucidated by the use of DNA probe (pDP34) for male-specific sequences of the Y chromosome. The presence of Y-specific fragments in the patient's DNA led to surgical exploration and the detection of a gonadoblastoma.

A child is reported who developed partial colonic obstruction from an intussuscepting polypoid mass in the transverse colon. A 5 cm plexiform ganglioneurofibroma was found at laparotomy. Examination of the entire gastrointestinal tract revealed no other neurogenic tumors. Gastrointestinal involvement by neurofibromatosis in children is rare; however, children with von Recklinghausen's disease who complain of vague abdominal symptoms should be evaluated for gastrointestinal tumors.

The malnourishing effects of cancer and its treatments haveprovided a strong clinical incentive for the nutritional support of cancer patients with intravenous hyperalimentation (IVH), but potential enhancement of tumor growth by additional substrate provision has generated concern. Twenty-five patients undergoing surgical treatment for gastrointestinal cancer were studied on one of two preoperative dietary regimens: ad libitum oral diet or intravenous hyperalimentation. Using a stable isotope tracer, N-glycine, in vivo tissue fractional protein synthesis rates were determined from operative specimens of tumor and normal gastrointestinal tissue. Despite substantial advantage in caloric and protein intake, and nitrogen retention, tumors in IVH-fed patients were synthesizing protein no faster (14.2%/day) than those in orally fed patients (15.1/day). Tumor fractional protein synthesis rates (PSRs) correlated (r = + 0.708, P less than 0.005) with the PSR of the tissues from which they arose. IVH maintained gut PSR at the level occurring in the orally fed patients. Parenteral nutritional support in cancer patients does not maintain protein synthesis rates at levels greater than those present with regular oral diets. Although not a direct measure of tumor growth, these data provide preliminary evidence that optimal nutritional support of the cancer patient may be possible without undesirable stimulation of tumor growth.

The substantial prevalence of malnutrition in the hospitalized patient population has only been recently recognized. Preoperative nutritional and immunological assessment was performed prospectively on admission in 64 consecutive surgical patients. Factors measured included weight loss, triceps skinfold, midarm muscle circumference, creatinine-height index, serum albumin level, serum transferrin level, total lymphocyte count, serum complement level, serum immunoelectrophoresis, lymphocyte T rosettes formation, neutrophil migration, and delayed hypersensitivity. Using these criteria for malnutrition, 97% of the patients had at least one abnormal measurement and 35% had at least three abnormal measurements. Patients were monitored for complications during their hospital course. Serum albumin level, serum transferrin level, and delayed hypersensitivity reactions were the only accurate prognostic indicators of postoperative morbidity and mortality. Substantial unrecognized malnutrition exists in the surgical patient population. An isolated indicator of malnutrition should be interpreted with caution. The visceral protein compartment (serum albumin and serum transferrin levels and delayed hypersensitivity) is the most accurate prognostic indicator of postoperative morbidity and mortality. Perioperative nutritional support may reduce operative morbidity and mortality in the malnourished operative candidate.

Kraske's methodology was classic: develop the operation in the laboratory, try it initially on patients as a last resort and, if it works, expand its use to patients with less severe disease. His operation immediately gained acceptance and was popular for the next quarter of a century. It was subsequently modified by Hochenagg, Billroth and Rydygier. These men merely altered the amount or manner of sacral removal. The operation was largely abandoned after Miles (3) showed that the lymphatic spread from carcinoma of the rectum is toward the liver. Kraske's procedure, however, stands as a landmark in preantibiotic operations on the colon. Combined with abdominal exploration, this type of procedure can be used to preserve the anus in certain instances of carcinoma of the rectum today.

The case report of a patient presenting with inferior vena caval obstruction secondary to ruptured abdominal aortic aneurysm is presented. The cause of the obstruction was not diagnosed prior to laparotomy. Management included replacement of the aneurysm, plication of the thrombosed inferior vena cava, and evacuation of the hematoma. So far as the authors are aware, this is the first case of this type to be reported and one which adds another possible diagnostic consideration in managing inferior vena caval obstruction.