3605 Hospital Road Suite H
Atwater CA 95301
Medical School: Other - Unknown
Accepts Medicare: No
Participates In eRX: No
Participates In PQRS: No
Participates In EHR: No
License #: D46093
Taxonomy Codes:1223G0001X 207L00000X
Request Appointment Information
Awards & Recognitions
Medical Malpractice Cases
Medical Board Sanctions
Quantifying the accuracy of the tumor motion and area as a function of acceleration factor for the simulation of the dynamic keyhole magnetic resonance imaging method. - Medical physics
The dynamic keyhole is a new MR image reconstruction method for thoracic and abdominal MR imaging. To date, this method has not been investigated with cancer patient magnetic resonance imaging (MRI) data. The goal of this study was to assess the dynamic keyhole method for the task of lung tumor localization using cine-MR images reconstructed in the presence of respiratory motion.The dynamic keyhole method utilizes a previously acquired a library of peripheral k-space datasets at similar displacement and phase (where phase is simply used to determine whether the breathing is inhale to exhale or exhale to inhale) respiratory bins in conjunction with central k-space datasets (keyhole) acquired. External respiratory signals drive the process of sorting, matching, and combining the two k-space streams for each respiratory bin, thereby achieving faster image acquisition without substantial motion artifacts. This study was the first that investigates the impact of k-space undersampling on lung tumor motion and area assessment across clinically available techniques (zero-filling and conventional keyhole). In this study, the dynamic keyhole, conventional keyhole and zero-filling methods were compared to full k-space dataset acquisition by quantifying (1) the keyhole size required for central k-space datasets for constant image quality across sixty four cine-MRI datasets from nine lung cancer patients, (2) the intensity difference between the original and reconstructed images in a constant keyhole size, and (3) the accuracy of tumor motion and area directly measured by tumor autocontouring.For constant image quality, the dynamic keyhole method, conventional keyhole, and zero-filling methods required 22%, 34%, and 49% of the keyhole size (P < 0.0001), respectively, compared to the full k-space image acquisition method. Compared to the conventional keyhole and zero-filling reconstructed images with the keyhole size utilized in the dynamic keyhole method, an average intensity difference of the dynamic keyhole reconstructed images (P < 0.0001) was minimal, and resulted in the accuracy of tumor motion within 99.6% (P < 0.0001) and the accuracy of tumor area within 98.0% (P < 0.0001) for lung tumor monitoring applications.This study demonstrates that the dynamic keyhole method is a promising technique for clinical applications such as image-guided radiation therapy requiring the MR monitoring of thoracic tumors. Based on the results from this study, the dynamic keyhole method could increase the imaging frequency by up to a factor of five compared with full k-space methods for real-time lung tumor MRI.
Audiovisual Biofeedback Improves Cine-Magnetic Resonance Imaging Measured Lung Tumor Motion Consistency. - International journal of radiation oncology, biology, physics
To assess the impact of an audiovisual (AV) biofeedback on intra- and interfraction tumor motion for lung cancer patients.Lung tumor motion was investigated in 9 lung cancer patients who underwent a breathing training session with AV biofeedback before 2 3T magnetic resonance imaging (MRI) sessions. The breathing training session was performed to allow patients to become familiar with AV biofeedback, which uses a guiding wave customized for each patient according to a reference breathing pattern. In the first MRI session (pretreatment), 2-dimensional cine-MR images with (1) free breathing (FB) and (2) AV biofeedback were obtained, and the second MRI session was repeated within 3-6 weeks (mid-treatment). Lung tumors were directly measured from cine-MR images using an auto-segmentation technique; the centroid and outlier motions of the lung tumors were measured from the segmented tumors. Free breathing and AV biofeedback were compared using several metrics: intra- and interfraction tumor motion consistency in displacement and period, and the outlier motion ratio.Compared with FB, AV biofeedback improved intrafraction tumor motion consistency by 34% in displacement (P=.019) and by 73% in period (P<.001). Compared with FB, AV biofeedback improved interfraction tumor motion consistency by 42% in displacement (P<.046) and by 74% in period (P=.005). Compared with FB, AV biofeedback reduced the outlier motion ratio by 21% (P<.001).These results demonstrated that AV biofeedback significantly improved intra- and interfraction lung tumor motion consistency for lung cancer patients. These results demonstrate that AV biofeedback can facilitate consistent tumor motion, which is advantageous toward achieving more accurate medical imaging and radiation therapy procedures.Copyright Â© 2016 Elsevier Inc. All rights reserved.
The practice of mediation to resolve clinical, bioethical, and medical malpractice disputes. - Hong Kong medical journal = Xianggang yi xue za zhi / Hong Kong Academy of Medicine
Mediation is a voluntary process whereby a neutral and impartial third party-t-he mediator--is present to facilitate communication and negotiation between the disputing parties so that amicable settlements can be agreed. Being confidential and non-adversarial in nature, the mediation process and skills are particularly applicable in clinical practice to facilitate challenging communications following adverse events, to assist bioethical decision making and to resolve disputes. Mediation is also a more effective and efficient means of dispute resolution in medical malpractice claims when compared with civil litigation. Health care mediation teams should be set up at individual facilities to provide education and consultation services to frontline staff and patients. At a community level, the Government, the mediation community, and the health care professionals should join forces to promote mediation as a means to settle medical malpractice claims outside of the courtroom.
Quantification of lung tumor rotation with automated landmark extraction using orthogonal cine MRI images. - Physics in medicine and biology
The quantification of tumor motion in sites affected by respiratory motion is of primary importance to improve treatment accuracy. To account for motion, different studies analyzed the translational component only, without focusing on the rotational component, which was quantified in a few studies on the prostate with implanted markers. The aim of our study was to propose a tool able to quantify lung tumor rotation without the use of internal markers, thus providing accurate motion detection close to critical structures such as the heart or liver. Specifically, we propose the use of an automatic feature extraction method in combination with the acquisition of fast orthogonal cine MRI images of nine lung patients. As a preliminary test, we evaluated the performance of the feature extraction method by applying it on regions of interest around (i) the diaphragm and (ii) the tumor and comparing the estimated motion with that obtained by (i) the extraction of the diaphragm profile and (ii) the segmentation of the tumor, respectively. The results confirmed the capability of the proposed method in quantifying tumor motion. Then, a point-based rigid registration was applied to the extracted tumor features between all frames to account for rotation. The median lung rotation values wereâ€‰â€‰-0.6â€‰â€‰â€‰Â±â€‰â€‰â€‰2.3Â° andâ€‰â€‰-1.5â€‰â€‰â€‰Â±â€‰â€‰â€‰2.7Â° in the sagittal and coronal planes respectively, confirming the need to account for tumor rotation along with translation to improve radiotherapy treatment.
An Overview of Testosterone Therapy. - American journal of men's health
Millions of men, as a result of the natural aging process, injury, illness, and medical therapies, experience a decline in testosterone levels that necessitate a need for testosterone supplementation therapy (TST). The signs and symptoms of testosterone decline may occur gradually, and low testosterone levels may be misdiagnosed as other medical conditions. Over the past two decades, there has been an increase in testing of testosterone levels and the use of TST. With so many men now on TST, it is essential for health care professionals to know the signs and symptoms, the causes of testosterone decline, how testosterone deficiency is diagnosed, what pathological changes are associated with testosterone decline, and the benefits and risks of TST. In addition, health care providers need to be aware of the various forms of testosterone available as well as the advantages and disadvantages of each. This article provides a brief overview of testosterone deficiency, TST treatment options and guidelines, and the risks and benefits associated with of TST.Â© The Author(s) 2014.
Development of a fluoride chronic effects benchmark for aquatic life in freshwater. - Environmental toxicology and chemistry / SETAC
Canada has an interim water-quality guideline for fluoride for protection of freshwater aquatic life that dates from 2002, and 1 Canadian province has a different interim water-quality guideline for fluoride that dates to 1995. The United States does not have a national benchmark for fluoride in freshwater, and only 1 US state has such a benchmark. There are no other national or regional benchmarks for fluoride chronic toxicity in freshwater. In the present study, available data on the acute and chronic toxicity of fluoride to freshwater aquatic life were compiled and reviewed. Acute toxicity was reported to occur at concentrations ranging from 11.5 to >800â€‰mg/L fluoride (F(-) ). The majority of chronic effects occur at concentrations between 1.8â€‰mg/L and 195â€‰mg/L. A total of 10 chronic studies representing 16 species (5 fish, 7 invertebrates, and 4 algae/aquatic plants) were used to derive a chronic effects benchmark of 1.94â€‰mg/L F(-) , applying the species sensitivity distribution approach.Â© 2014 SETAC.
Dynamic keyhole: a novel method to improve MR images in the presence of respiratory motion for real-time MRI. - Medical physics
In this work, the authors present a novel magnetic resonance imaging reconstruction method to improve the quality of MR images in the presence of respiratory motion for real-time thoracic image-guided radiotherapy.This new reconstruction method is called dynamic keyhole and utilizes a library of previously acquired, peripheral k-space datasets from the same (or similar) respiratory state in conjunction with central k-space datasets acquired in real-time. Internal or external respiratory signals are utilized to sort, match, and combine the two separate peripheral and central k-space datasets with respect to respiratory displacement, thereby reducing acquisition time and improving image quality without respiratory-related artifacts. In this study, the dynamic keyhole, conventional keyhole, and zero-filling methods were compared to full k-space acquisition (ground truth) for 60 coronal datasets acquired from 15 healthy human subjects.For the same image-quality difference from the ground-truth image, the dynamic keyhole method reused 79% of the prior peripheral phase-encoding lines, while the conventional keyhole reused 73% and zero-filling 63% (p-value < 0.0001), corresponding to faster acquisition speed of dynamic keyhole for real-time imaging applications.This study demonstrates that the dynamic keyhole method is a promising technique for clinical applications such as image-guided radiotherapy requiring real-time MR monitoring of the thoracic region. Based on the results from this study, the dynamic keyhole method could increase the temporal resolution by a factor of five compared with full k-space methods.
In vitro biotransformation rates in fish liver S9: effect of dosing techniques. - Environmental toxicology and chemistry / SETAC
In vitro biotransformation assays are currently being explored to improve estimates of bioconcentration factors of potentially bioaccumulative organic chemicals in fish. The present study compares thin-film and solvent-delivery dosing techniques as well as single versus multiple chemical dosing for measuring biotransformation rates of selected polycyclic aromatic hydrocarbons in rainbow trout (Oncorhynchus mykiss) liver S9. The findings show that biotransformation rates of very hydrophobic substances can be accurately measured in thin-film sorbent-dosing assays from concentration-time profiles in the incubation medium but not from those in the sorbent phase because of low chemical film-to-incubation-medium mass-transfer rates at the incubation temperature of 13.5â€‰Â°C required for trout liver assays. Biotransformation rates determined by thin-film dosing were greater than those determined by solvent-delivery dosing for chrysene (octanol-water partition coefficient [KOW ]â€‰=10(5.60) ) and benzo[a]pyrene (KOW â€‰=10(6.04) ), whereas there were no statistical differences in pyrene (KOW â€‰=10(5.18) ) biotransformation rates between the 2 methods. In sorbent delivery-based assays, simultaneous multiple-chemical dosing produced biotransformation rates that were not statistically different from those measured in single-chemical dosing experiments for pyrene and benzo[a]pyrene but not for chrysene. In solvent-delivery experiments, multiple-chemical dosing produced biotransformation rates that were much smaller than those in single-chemical dosing experiments for all test chemicals. While thin-film sorbent-phase and solvent delivery-based dosing methods are both suitable methods for measuring biotransformation rates of substances of intermediate hydrophobicity, thin-film sorbent-phase dosing may be more suitable for superhydrophobic chemicals.Â© 2014 SETAC.
The internal-external respiratory motion correlation is unaffected by audiovisual biofeedback. - Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine
This study evaluated if an audiovisual (AV) biofeedback causes variation in the level of external and internal correlation due to its interactive intervention in natural breathing. The internal (diaphragm) and external (abdominal wall) respiratory motion signals of 15 healthy human subjects under AV biofeedback and free breathing (FB) were analyzed and measures of correlation and regularity taken. Regularity metrics (root mean square error and spectral power dispersion metric) were obtained and the correlation between these metrics and the internal and external correlation was investigated. For FB and AV biofeedback assisted breathing the mean correlations found between internal and external respiratory motion were 0.96Â±0.02 and 0.96Â±0.03, respectively. This means there is no evidence to suggest (p-value=0.88) any difference in the correlation between internal and external respiratory motion with the use of AV biofeedback. Our results confirmed the hypothesis that the internal-external correlation with AV biofeedback is the same as for free breathing. Should this correlation be maintained for patients, AV biofeedback can be implemented in the clinic with confidence as regularity improvements using AV biofeedback with an external signal will be reflected in increased internal motion regularity.
Laparoscopic sleeve gastrectomy with loop bipartition: A novel metabolic operation in treating obese type II diabetes mellitus. - International journal of surgery case reports
We report the first case of laparoscopic sleeve gastrectomy with loop bipartition (a modified form of Santoro's operation) in the treatment of type II diabetes mellitus associated with obesity.A 46-year-old gentleman (baseline BMI 32.9; BW 98.5kg) with 7-year history of type II diabetes mellitus (DM) underwent the procedure in Hong Kong. The control of DM was poor even with intensive medical therapy before the operation. Standard laparoscopic sleeve gastrectomy (SG) was performed and a loop gastroileostomy was fashioned at the antrum 250cm from the ilececal valve without division of the 1st part of duodenum after SG. The resultant gastric tube has two outlets, one to the first part of duodenum and the other to the ileum with preferential passage of food through the gastroileostomy as shown on subsequent contrast study. The patient's recovery was uneventful. The excess BMI loss was 97% with complete normalization of all metabolic parameters at 1-year follow-up.This new surgical procedure (sleeve gastrectomy with loop bipartition: SG+LB) was evolved and derived from the combined concepts of sleeve gastrectomy with transit bipartition (SG+TB), single anastomosis duodenal-ileostomy (SADI), mini-gastric bypass (MGB) and duodenal-jejunal bypass (DJB) with less nutritional and surgical complications.Sleeve gastrectomy with loop bipartition may be a very effective and simple operation to treat uncontrolled DM associated with obesity with a lot of apparent advantages over most current metabolic procedures available at the moment.Copyright Â© 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.
Map & Directions
3605 Hospital Road Suite H Atwater, CA 95301
1000 Commerce Ave Target Optical