Quantification of Diaphragm Mechanics in Pompe Disease Using Dynamic 3D MRI.

Directory of Open Access Journals (Sweden)

Katja Mogalle

Full Text Available Diaphragm weakness is the main reason for respiratory dysfunction in patients with Pompe disease, a progressive metabolic myopathy affecting respiratory and limb-girdle muscles. Since respiratory failure is the major cause of death among adult patients, early identification of respiratory muscle involvement is necessary to initiate treatment in time and possibly prevent irreversible damage. In this paper we investigate the suitability of dynamic MR imaging in combination with state-of-the-art image analysis methods to assess respiratory muscle weakness.The proposed methodology relies on image registration and lung surface extraction to quantify lung kinematics during breathing. This allows for the extraction of geometry and motion features of the lung that characterize the independent contribution of the diaphragm and the thoracic muscles to the respiratory cycle.Results in 16 3D+t MRI scans (10 Pompe patients and 6 controls of a slow expiratory maneuver show that kinematic analysis from dynamic 3D images reveals important additional information about diaphragm mechanics and respiratory muscle involvement when compared to conventional pulmonary function tests. Pompe patients with severely reduced pulmonary function showed severe diaphragm weakness presented by minimal motion of the diaphragm. In patients with moderately reduced pulmonary function, cranial displacement of posterior diaphragm parts was reduced and the diaphragm dome was oriented more horizontally at full inspiration compared to healthy controls.Dynamic 3D MRI provides data for analyzing the contribution of both diaphragm and thoracic muscles independently. The proposed image analysis method has the potential to detect less severe diaphragm weakness and could thus be used to determine the optimal start of treatment in adult patients with Pompe disease in prospect of increased treatment response.

Determination of ventilatory liver movement via radiographic evaluation of diaphragm position

International Nuclear Information System (INIS)

Balter, James M.; Dawson, Laura A.; Kazanjian, Sahira; McGinn, Cornelius; Brock, Kristy K.; Lawrence, Theodore; Haken, Randall ten

2001-01-01

Purpose: To determine the accuracy of estimation of liver movement inferred by observing diaphragm excursion on radiographic images. Methods and Materials: Eight patients with focal liver cancer had platinum embolization microcoils implanted in their livers during catheterization of the hepatic artery for delivery of regional chemotherapy. These patients underwent fluoroscopy, during which normal breathing movement was recorded on videotape. Movies of breathing movement were digitized, and the relative projected positions of the diaphragm and coils were recorded. For 6 patients, daily radiographs were also acquired during treatment. Retrospective measurements of coil position were taken after the diaphragm was aligned with the superior portion of the liver on digitally reconstructed radiographs. Results: Coil movement of 4.9 to 30.4 mm was observed during normal breathing. Diaphragm position tracked inferior-superior coil displacement accurately (population σ 1.04 mm) throughout the breathing cycle. The range of coil movement was predicted by the range of diaphragm movement with an accuracy of 2.09 mm (σ). The maximum error observed measuring coil movement using diaphragm position was 3.8 mm for a coil 9.8 cm inferior to the diaphragm. However, the distance of the coil from the top of the diaphragm did not correlate significantly with the error in predicting liver excursion. Analysis of daily radiographs showed that the error in predicting coil position using the diaphragm as an alignment landmark was 1.8 mm (σ) in the inferior-superior direction and 2.2 mm in the left-right direction, similar in magnitude to the inherent uncertainty in alignment. Conclusions: This study demonstrated that the range of ventilatory movement of different locations within the liver is predicted by diaphragm position to an accuracy that matches or exceeds existing systems for ventilatory tracking. This suggests that the diaphragm is an acceptable anatomic landmark for radiographic

MDCT diagnosis of penetrating diaphragm injury

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Bodanapally, Uttam K.; Shanmuganathan, Kathirkamanathan; Mirvis, Stuart E.; Sliker, Clint W.; Fleiter, Thorsten R.; Sarada, Kamal; Miller, Lisa A. [University of Maryland School of Medicine, Department of Diagnostic Radiology, Baltimore, MD (United States); Stein, Deborah M. [University of Maryland, Department of Surgery, Shock Trauma Center, Baltimore, MD (United States); Alexander, Melvin [National Study Center for Trauma and Emergency Medical Systems, Baltimore, MD (United States)

2009-08-15

The purpose of the study was to determine the diagnostic sensitivity and specificity of multidetector CT (MDCT) in detection of diaphragmatic injury following penetrating trauma. Chest and abdominal CT examinations performed preoperatively in 136 patients after penetrating trauma to the torso with injury trajectory in close proximity to the diaphragm were reviewed by radiologists unaware of surgical findings. Signs associated with diaphragmatic injuries in penetrating trauma were noted. These signs were correlated with surgical diagnoses, and their sensitivity and specificity in assisting the diagnosis were calculated. CT confirmed diaphragmatic injury in 41 of 47 injuries (sensitivity, 87.2%), and an intact diaphragm in 71 of 98 patients (specificity, 72.4%). The overall accuracy of MDCT was 77%. The most accurate sign helping the diagnosis was contiguous injury on either side of the diaphragm in single-entry penetrating trauma (sensitivity, 88%; specificity, 82%). Thus MDCT has high sensitivity and good specificity in detecting penetrating diaphragmatic injuries. (orig.)

MDCT diagnosis of penetrating diaphragm injury

International Nuclear Information System (INIS)

Bodanapally, Uttam K.; Shanmuganathan, Kathirkamanathan; Mirvis, Stuart E.; Sliker, Clint W.; Fleiter, Thorsten R.; Sarada, Kamal; Miller, Lisa A.; Stein, Deborah M.; Alexander, Melvin

2009-01-01

The purpose of the study was to determine the diagnostic sensitivity and specificity of multidetector CT (MDCT) in detection of diaphragmatic injury following penetrating trauma. Chest and abdominal CT examinations performed preoperatively in 136 patients after penetrating trauma to the torso with injury trajectory in close proximity to the diaphragm were reviewed by radiologists unaware of surgical findings. Signs associated with diaphragmatic injuries in penetrating trauma were noted. These signs were correlated with surgical diagnoses, and their sensitivity and specificity in assisting the diagnosis were calculated. CT confirmed diaphragmatic injury in 41 of 47 injuries (sensitivity, 87.2%), and an intact diaphragm in 71 of 98 patients (specificity, 72.4%). The overall accuracy of MDCT was 77%. The most accurate sign helping the diagnosis was contiguous injury on either side of the diaphragm in single-entry penetrating trauma (sensitivity, 88%; specificity, 82%). Thus MDCT has high sensitivity and good specificity in detecting penetrating diaphragmatic injuries. (orig.)

High Dk piggyback contact lens system for contact lens-intolerant keratoconus patients.

Science.gov (United States)

Sengor, Tomris; Kurna, Sevda Aydin; Aki, Suat; Ozkurt, Yelda

2011-01-01

The aim of the study was to examine the clinical success of high Dk (oxygen permeability) piggyback contact lens (PBCL) systems for the correction of contact lens intolerant keratoconus patients. Sixteen patients (29 eyes) who were not able to wear gas-permeable rigid lenses were included in this study. Hyper Dk silicone hydrogel (oxygen transmissibility or Dk/t = 150 units) and fluorosilicone methacrylate copolymer (Dk/t = 100 units) lenses were chosen as the PBCL systems. The clinical examinations included visual acuity and corneal observation by biomicroscopy, keratometer reading, and fluorescein staining before and after fitting the PBCL system. INDICATIONS FOR USING PBCL SYSTEM WERE: lens stabilization and comfort, improving comfort, and adding protection to the cone. Visual acuities increased significantly in all of the patients compared with spectacles (P = 0). Improvement in visual acuity compared with rigid lenses alone was recorded in 89.7% of eyes and no alteration of the visual acuity was observed in 10.3% of the eyes. Wearing time of PBCL systems for most of the patients was limited time (mean 6 months, range 3-12 months); thereafter they tolerated rigid lenses alone except for 2 patients. The PBCL system is a safe and effective method to provide centering and corneal protection against mechanical trauma by the rigid lenses for keratoconus patients and may increase contact lens tolerance.

Four-Dimensional CT of the Diaphragm in Children: Initial Experience

Science.gov (United States)

2018-01-01

Objective To evaluate the technical feasibility of four-dimensional (4D) CT for the functional evaluation of the pediatric diaphragm. Materials and Methods In 22 consecutive children (median age 3.5 months, age range 3 days–3 years), 4D CT was performed to assess diaphragm motion. Diaphragm abnormalities were qualitatively evaluated and diaphragm motion was quantitatively measured on 4D CT. Lung density changes between peak inspiration and expiration were measured in the basal lung parenchyma. The diaphragm motions and lung density changes measured on 4D CT were compared between various diaphragm conditions. In 11 of the 22 children, chest sonography was available for comparison. Results Four-dimensional CT demonstrated normal diaphragm (n = 8), paralysis (n = 10), eventration (n = 3), and diffusely decreased motion (n = 1). Chest sonography demonstrated normal diaphragm (n = 2), paralysis (n = 6), eventration (n = 2), and right pleural effusion (n = 1). The sonographic findings were concordant with the 4D CT findings in 90.9% (10/11) of the patients. In diaphragm paralysis, the affected diaphragm motion was significantly decreased compared with the contralateral normal diaphragm motion (−1.1 ± 2.2 mm vs. 7.6 ± 3.8 mm, p = 0.005). The normal diaphragms showed significantly greater motion than the paralyzed diaphragms (4.5 ± 2.1 mm vs. −1.1 ± 2.2 mm, p Hounsfield units [HU] vs. 180 ± 71 HU, p = 0.03), while no significant differences were found between the normal diaphragms and the paralyzed diaphragms (136 ± 66 HU vs. 89 ± 73 HU, p = 0.1) or between the normal diaphragms and the contralateral normal diaphragms in paralysis (136 ± 66 HU vs. 180 ± 71 HU, p = 0.1). Conclusion The functional evaluation of the pediatric diaphragm is feasible with 4D CT in select children. PMID:29354007

[Diaphragm pacing for the ventilatory support of the quadriplegic patients with respiratory paralysis].

Science.gov (United States)

Cheng, H; Wang, L S; Pan, H C; Shoung, H M; Lee, L S

1992-02-01

Electrical stimulation of the phrenic nerve to pace the diaphragm in patients with chronic ventilatory insufficiency has been an established therapeutic modality since William W.L. Glenn first described using radiofrequency signals in 1978 to stimulate the phrenic nerves. Before this event, patients who were ventilator-dependent and thus bedridden because of respiratory paralysis associated with quadriplegia usually anticipated little chance for physical or psychosocial rehabilitation. Two cases of C1-C2 subluxtion with cord injury and chronic ventilatory insufficiency were implanted at VGH-Taipei with diaphragm pacemaker in 1988. Postoperative phrenic nerve stimulation was given according to individual training schedule. One case with total phrenic paralysis received bilateral phrenic nerve stimulation and became weaned from the ventilator 6 months later. The other case with partially active ventilatory function received unilateral phrenic nerve stimulation to compensate the ventilation. However, its final outcome still showed the necessity of a bilateral mode to achieve adequate ventilation irrespective of strenuous training for 2 years.

Design of pressure-sensing diaphragm for MEMS capacitance diaphragm gauge considering size effect

Science.gov (United States)

Li, Gang; Li, Detian; Cheng, Yongjun; Sun, Wenjun; Han, Xiaodong; Wang, Chengxiang

2018-03-01

MEMS capacitance diaphragm gauge with a full range of (1˜1000) Pa is considered for its wide application prospect. The design of pressure-sensing diaphragm is the key to achieve balanced performance for this kind of gauges. The optimization process of the pressure-sensing diaphragm with island design of a capacitance diaphragm gauge based on MEMS technique has been reported in this work. For micro-components in micro scale range, mechanical properties are very different from that in the macro scale range, so the size effect should not be ignored. The modified strain gradient elasticity theory considering size effect has been applied to determine the bending rigidity of the pressure-sensing diaphragm, which is then used in the numerical model to calculate the deflection-pressure relation of the diaphragm. According to the deflection curves, capacitance variation can be determined by integrating over the radius of the diaphragm. At last, the design of the diaphragm has been optimized based on three parameters: sensitivity, linearity and ground capacitance. With this design, a full range of (1˜1000) Pa can be achieved, meanwhile, balanced sensitivity, resolution and linearity can be kept.

Is Diaphragm Motion a Good Surrogate for Liver Tumor Motion?

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Yang, Juan [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); School of Information Science and Engineering, Shandong University, Jinan, Shandong (China); Cai, Jing [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Wang, Hongjun [School of Information Science and Engineering, Shandong University, Jinan, Shandong (China); Chang, Zheng; Czito, Brian G. [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Bashir, Mustafa R. [Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States); Palta, Manisha [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Yin, Fang-Fang, E-mail: fangfang.yin@duke.edu [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States)

2014-11-15

Purpose: To evaluate the relationship between liver tumor motion and diaphragm motion. Methods and Materials: Fourteen patients with hepatocellular carcinoma (10 of 14) or liver metastases (4 of 14) undergoing radiation therapy were included in this study. All patients underwent single-slice cine–magnetic resonance imaging simulations across the center of the tumor in 3 orthogonal planes. Tumor and diaphragm motion trajectories in the superior–inferior (SI), anterior–posterior (AP), and medial–lateral (ML) directions were obtained using an in-house-developed normalized cross-correlation–based tracking technique. Agreement between the tumor and diaphragm motion was assessed by calculating phase difference percentage, intraclass correlation coefficient, and Bland-Altman analysis (Diff). The distance between the tumor and tracked diaphragm area was analyzed to understand its impact on the correlation between the 2 motions. Results: Of all patients, the mean (±standard deviation) phase difference percentage values were 7.1% ± 1.1%, 4.5% ± 0.5%, and 17.5% ± 4.5% in the SI, AP, and ML directions, respectively. The mean intraclass correlation coefficient values were 0.98 ± 0.02, 0.97 ± 0.02, and 0.08 ± 0.06 in the SI, AP, and ML directions, respectively. The mean Diff values were 2.8 ± 1.4 mm, 2.4 ± 1.1 mm, and 2.2 ± 0.5 mm in the SI, AP, and ML directions, respectively. Tumor and diaphragm motions had high concordance when the distance between the tumor and tracked diaphragm area was small. Conclusions: This study showed that liver tumor motion had good correlation with diaphragm motion in the SI and AP directions, indicating diaphragm motion in the SI and AP directions could potentially be used as a reliable surrogate for liver tumor motion.

Therapeutic effects of diaphragmatic plication for acquired unilateral non-malignant diaphragm paralysis in twenty patients

Directory of Open Access Journals (Sweden)

Reza Bagheri

2013-12-01

Full Text Available Background: Acquired paralysis of the diaphragm is a condition caused by trauma, surgical injuries, (lung cancer surgery, esophageal surgery, cardiac surgery, thoracic surgery, and is sometimes of an unknown etiology. It can lead to dyspnea and can affect ventilatory function and patients activity. Diaphragmatic plication is a treatment method which decreases inconsistent function of diaphragm. The aim of this study is to evaluate the outcome of diaphragmatic plication in patients with acquired unilateral non-malignant diaphragmatic paralysis. Methods: From 1991 to 2011, 20 patients with acquired unilateral diaphragmatic paralysis who underwent surgery enrolled in our study in Ghaem Hospital Mashhad University of Medical Science. Patients were evaluated in terms of age, sex, BMI, clinical symptoms, dyspnea score (DS, etiology of paralysis, diagnostic methods, respiratory function tests and complication of surgery. Some tests including dyspnea score were carried out again six months after surgery. We evaluated patients with SPSS version 11.5 and Paired t-test or nonparametric equivalent. Results: Twenty patients enrolled in our study. 14 were male and 6 were female. The mean age was 58 years and the average time interval between diagnosis to surgical treatment was 38.3 months. Acquired diaphragmatic paralysis was mostly caused by trauma (in 11 patients and almost occurred on the left side (in 15 patients. Diagnostic methods included chest x-ray, CT scan, ultrasonography and sniff. Test prior to surgery the average FVC was 41.4±7 percent and the average FEV1 was 52.4±6 percent and after surgery they were 80.1±8.6 percent and 74.4±1 percent respectively. The average increase in FEV1 and FVC 63.4±4, 61.1±7.8. Performing surgery also leads to a noticeable improvement in dyspnea score in our study. Conclusion: In patients with acquired unilateral non-malignant diaphragm paralysis diaphragmatic plication is highly recommended due to the

Idiopathic diaphragmatic paralysis: Bell's palsy of the diaphragm?

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Crausman, Robert S; Summerhill, Eleanor M; McCool, F Dennis

2009-01-01

Idiopathic diaphragm paralysis is probably more common and responsible for more morbidity than generally appreciated. Bell's palsy, or idiopathic paralysis of the seventh cranial nerve, may be seen as an analogous condition. The roles of zoster sine herpete and herpes simplex have increasingly been recognized in Bell's palsy, and there are some data to suggest that antiviral therapy is a useful adjunct to steroid therapy. Thus, we postulated that antiviral therapy might have a positive impact on the course of acute idiopathic diaphragm paralysis which is likely related to viral infection. Three consecutive patients with subacute onset of symptomatic idiopathic hemidiaphragm paralysis were empirically treated with valacyclovir, 1,000 mg twice daily for 1 week. Prior to therapy, diaphragmatic function was assessed via pulmonary function testing and two-dimensional B-mode ultrasound, with testing repeated 1 month later. Diaphragmatic function pre- and post-treatment was compared to that of a historical control group of 16 untreated patients. All three subjects demonstrated ultrasound recovery of diaphragm function 4-6 weeks following treatment with valacyclovir. This recovery was accompanied by improvements in maximum inspiratory pressure (PI(max)) and vital capacity (VC). In contrast, in the untreated cohort, diaphragm recovery occurred in only 11 subjects, taking an average of 14.9 +/- 6.1 months (mean +/- SD). The results of this small, preliminary study suggest that antiviral therapy with valacyclovir may be helpful in the treatment of idiopathic diaphragm paralysis induced by a viral infection.

First reported experience with intramuscular diaphragm pacing in replacing positive pressure mechanical ventilators in children.

Science.gov (United States)

Onders, Raymond P; Ponsky, Todd A; Elmo, MaryJo; Lidsky, Karen; Barksdale, Edward

2011-01-01

Diaphragm pacing (DP) has been shown to successfully replace mechanical ventilators for adult tetraplegic patients with chronic respiratory insufficiency. This is the first report of DP in ventilator-dependent children. This was a prospective interventional experience under institutional review board approval. Diaphragm pacing involves outpatient laparoscopic diaphragm motor point mapping to identify the site where stimulation causes maximum diaphragm contraction with implantation of 4 percutaneous intramuscular electrodes. Diaphragm conditioning ensues to wean the child from the ventilator. Six children were successfully implanted ranging from 5 to 17 years old with the smallest 15 kg in weight. Length of time on mechanical ventilation ranged from 11 days to 7.6 years with an average of 3.2 years. In all patients, DP provided tidal volumes above basal needs. Five of the patients underwent a home-based weaning program, whereas one patient who was implanted only 11 days post spinal cord injury never returned to the ventilator with DP use. Another patient was weaned from the ventilator full time but died of complications of his underlying brain stem tumor. The remaining patients weaned from the ventilator for over 14 hours a day and/or are actively conditioning their diaphragms. Diaphragm pacing successfully replaced mechanical ventilators, which improves quality of life. Copyright © 2011 Elsevier Inc. All rights reserved.

Paper-thinned diaphragm: CT sign of diaphragmatic eventration

International Nuclear Information System (INIS)

Im, Jung Gi; Han, Man Chung; Kim, Chu Wan; Shim, Young Soo

1990-01-01

CT findings of total left hemidiaphragmatic eventration in two adult patients are described. Chest radiograph showed elevated left hemidiaphragm and left hilum. Paper-thinned muscular portion of the diseased diaphragm was clearly demonstrated with CT scan. With demonstration of paper-thinned diaphragm by CT scan, differentiation of the diaphragmatic eventration from recent onset phrenic nerve paralysis by tumor invasion or from post-traumatic diaphragmatic hernia can be made

Paper-thinned diaphragm: CT sign of diaphragmatic eventration

Energy Technology Data Exchange (ETDEWEB)

Im, Jung Gi; Han, Man Chung; Kim, Chu Wan; Shim, Young Soo [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

1990-10-15

CT findings of total left hemidiaphragmatic eventration in two adult patients are described. Chest radiograph showed elevated left hemidiaphragm and left hilum. Paper-thinned muscular portion of the diseased diaphragm was clearly demonstrated with CT scan. With demonstration of paper-thinned diaphragm by CT scan, differentiation of the diaphragmatic eventration from recent onset phrenic nerve paralysis by tumor invasion or from post-traumatic diaphragmatic hernia can be made.

Quantification of diaphragm mechanics in Pompe disease using dynamic 3D MRI

DEFF Research Database (Denmark)

Mogalle, Katja; Perez-Rovira, Adria; Ciet, Pierluigi

2016-01-01

BACKGROUND: Diaphragm weakness is the main reason for respiratory dysfunction in patients with Pompe disease, a progressive metabolic myopathy affecting respiratory and limb-girdle muscles. Since respiratory failure is the major cause of death among adult patients, early identification of respira......BACKGROUND: Diaphragm weakness is the main reason for respiratory dysfunction in patients with Pompe disease, a progressive metabolic myopathy affecting respiratory and limb-girdle muscles. Since respiratory failure is the major cause of death among adult patients, early identification...... methodology relies on image registration and lung surface extraction to quantify lung kinematics during breathing. This allows for the extraction of geometry and motion features of the lung that characterize the independent contribution of the diaphragm and the thoracic muscles to the respiratory cycle....... RESULTS: Results in 16 3D+t MRI scans (10 Pompe patients and 6 controls) of a slow expiratory maneuver show that kinematic analysis from dynamic 3D images reveals important additional information about diaphragm mechanics and respiratory muscle involvement when compared to conventional pulmonary function...

β-hydroxy-β-methylbutyrate (HMB) prevents sepsis-induced diaphragm dysfunction in mice.

Science.gov (United States)

Supinski, Gerald S; Callahan, Leigh A

2014-06-01

Infections induce severe respiratory muscle weakness. Currently there are no treatments for this important clinical problem. We tested the hypothesis that β-hydroxy-β-methylbutyrate (HMB) would prevent sepsis-induced diaphragm weakness. Four groups of adult male mice were studied: controls (saline-injected), sepsis (intraperitoneal lipopolysaccharide), sepsis+HMB (injected intravenously), and HMB. Diaphragm force generation and indices of caspase 3, calpain, 20S proteasomal subunit, and double-stranded RNA-dependent protein kinase (PKR) activation were assessed after 24h. Sepsis elicited large reductions in diaphragm specific force generation at all stimulation frequencies. Endotoxin also activated caspase 3, calpain, the 20S proteasomal subunit and PKR in the diaphragm. HMB blocked sepsis-induced caspase 3, 20S proteasomal and PKR activation, but did not prevent calpain activation. Most importantly, HMB administration significantly attenuated sepsis-induced diaphragm weakness, preserving muscle force generation at all stimulation frequencies (pHMB may prove to be an important therapy in infected patients, with the potential to increase diaphragm strength, to reduce the duration of mechanical ventilation and to decrease mortality in this patient population. Copyright © 2014 Elsevier B.V. All rights reserved.

Iris reconstruction combined with iris-claw intraocular lens implantation for the management of iris-lens injured patients.

Science.gov (United States)

Hu, Shufang; Wang, Mingling; Xiao, Tianlin; Zhao, Zhenquan

2016-03-01

To study the efficiency and safety of iris reconstruction combined with iris-claw intraocular lens (IOL) implantation in the patients with iris-lens injuries. Retrospective, noncomparable consecutive case series study. Eleven patients (11 eyes) following iris-lens injuries underwent iris reconstructions combined with iris-claw IOL implantations. Clinical data, such as cause and time of injury, visual acuity (VA), iris and lens injuries, surgical intervention, follow-up period, corneal endothelial cell count, and optical coherence tomography, were collected. Uncorrected VA (UCVA) in all injured eyes before combined surgery was equal to or iris returned to its natural round shape or smaller pupil, and the iris-claw IOLs in the 11 eyes were well-positioned on the anterior surface of reconstructed iris. No complications occurred in those patients. Iris reconstruction combined with iris-claw IOL implantation is a safe and efficient procedure for an eye with iris-lens injury in the absence of capsular support.

Barrier Methods of Birth Control: Spermicide, Condom, Sponge, Diaphragm, and Cervical Cap

Science.gov (United States)

... ACOG Barrier Methods of Birth Control: Spermicide, Condom, Sponge, Diaphragm, and Cervical Cap Home For Patients Search ... Format Barrier Methods of Birth Control: Spermicide, Condom, Sponge, Diaphragm, and Cervical Cap Contraception What are barrier ...

Quantifying the predictability of diaphragm motion during respiration with a noninvasive external marker

International Nuclear Information System (INIS)

Vedam, S.S.; Kini, V.R.; Keall, P.J.; Ramakrishnan, V.; Mostafavi, H.; Mohan, R.

2003-01-01

The aim of this work was to quantify the ability to predict intrafraction diaphragm motion from an external respiration signal during a course of radiotherapy. The data obtained included diaphragm motion traces from 63 fluoroscopic lung procedures for 5 patients, acquired simultaneously with respiratory motion signals (an infrared camera-based system was used to track abdominal wall motion). During these sessions, the patients were asked to breathe either (i) without instruction, (ii) with audio prompting, or (iii) using visual feedback. A statistical general linear model was formulated to describe the relationship between the respiration signal and diaphragm motion over all sessions and for all breathing training types. The model parameters derived from the first session for each patient were then used to predict the diaphragm motion for subsequent sessions based on the respiration signal. Quantification of the difference between the predicted and actual motion during each session determined our ability to predict diaphragm motion during a course of radiotherapy. This measure of diaphragm motion was also used to estimate clinical target volume (CTV) to planning target volume (PTV) margins for conventional, gated, and proposed four-dimensional (4D) radiotherapy. Results from statistical analysis indicated a strong linear relationship between the respiration signal and diaphragm motion (p<0.001) over all sessions, irrespective of session number (p=0.98) and breathing training type (p=0.19). Using model parameters obtained from the first session, diaphragm motion was predicted in subsequent sessions to within 0.1 cm (1 σ) for gated and 4D radiotherapy. Assuming a 0.4 cm setup error, superior-inferior CTV-PTV margins of 1.1 cm for conventional radiotherapy could be reduced to 0.8 cm for gated and 4D radiotherapy. The diaphragm motion is strongly correlated with the respiration signal obtained from the abdominal wall. This correlation can be used to predict diaphragm

Radial-Electric-Field Piezoelectric Diaphragm Pumps

Science.gov (United States)

Bryant, Robert G.; Working, Dennis C.; Mossi, Karla; Castro, Nicholas D.; Mane, Pooma

2009-01-01

In a recently invented class of piezoelectric diaphragm pumps, the electrode patterns on the piezoelectric diaphragms are configured so that the electric fields in the diaphragms have symmetrical radial (along-the-surface) components in addition to through-the-thickness components. Previously, it was accepted in the piezoelectric-transducer art that in order to produce the out-of-plane bending displacement of a diaphragm needed for pumping, one must make the electric field asymmetrical through the thickness, typically by means of electrodes placed on only one side of the piezoelectric material. In the present invention, electrodes are placed on both sides and patterned so as to produce substantial radial as well as through-the-thickness components. Moreover, unlike in the prior art, the electric field can be symmetrical through the thickness. Tests have shown in a given diaphragm that an electrode configuration according to this invention produces more displacement than does a conventional one-sided electrode pattern. The invention admits of numerous variations characterized by various degrees of complexity. Figure 1 is a simplified depiction of a basic version. As in other piezoelectric diaphragm pumps of similar basic design, the prime mover is a piezoelectric diaphragm. Application of a suitable voltage to the electrodes on the diaphragm causes it to undergo out-of-plane bending. The bending displacement pushes a fluid out of, or pulls the fluid into, a chamber bounded partly by the diaphragm. Also as in other diaphragm pumps in general, check valves ensure that the fluid flows only in through one port and only out through another port.

Transient anterior subcapsular vacuolar change of the crystalline lens in patients after posterior chamber phakic intraocular lens implantation.

Science.gov (United States)

Chung, Jin Kwon; Shin, Jin Hee; Lee, Sung Jin

2013-10-25

We present two cases of transient vacuolar changes in the anterior subcapsular space of the crystalline lens in patients after posterior chamber phakic intraocular lens implantation. Implantable collamer lenses (ICL) were implanted in healthy myopic patients. Vacuolar changes developed just after the irrigating procedure through the narrow space between the ICL and the crystalline lens. Slit-lamp examinations and spectral domain optical coherence tomography showed bleb-like lesions in the anterior subcapsular space of one eye in each case, though the lesions gradually improved without visual deterioration. Consequently, the lesions turned into a few anterior subcapsular small faint opacities. Direct irrigation of the narrow space confined by the ICL and the crystalline lens is at risk for the development of vacuolar changes in the crystalline lens. The observed spontaneous reversal indicates that surgeons should not rush to surgical intervention but rather opt for close follow over several weeks.

Cough induced rib fracture, rupture of the diaphragm and abdominal herniation

Directory of Open Access Journals (Sweden)

Wurl Peter

2006-11-01

Full Text Available Abstract Cough can be associated with many complications. In this article, we present a 59 year old male patient with a very rare combination of a cough related stress fracture of the ninth rib, a traumatic rupture of the diaphragm, and an abdominal wall herniation. The hernia was repaired through surgical treatment without bowel resection, the diaphragm and the internal and oblique abdominal muscle were adapted, and the abdomen was reinforced with a prolene net. Although each individual injury is well documented in the literature, the combination of rib fracture, abdominal herniation and diaphragm rupture has not been reported.

TU-E-201-00: Eye Lens Dosimetry for Patients and Staff

Energy Technology Data Exchange (ETDEWEB)

NONE

2015-06-15

Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bomb survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on

TU-E-201-00: Eye Lens Dosimetry for Patients and Staff

International Nuclear Information System (INIS)

2015-01-01

Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bomb survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on

New Stethoscope With Extensible Diaphragm.

Science.gov (United States)

Takashina, Tsunekazu; Shimizu, Masashi; Muratake, Torakazu; Mayuzumi, Syuichi

2016-08-25

This study compared the diagnostic efficacy of the common suspended diaphragm stethoscope (SDS) with a new extensible diaphragm stethoscope (EDS) for low-frequency heart sounds. The EDS was developed by using an ethylene propylene diene monomer diaphragm. The results showed that the EDS enhanced both the volume and quality of low-frequency heart sounds, and improved the ability of examiners to auscultate such heart sounds. Based on the results of the sound analysis, the EDS is more efficient than the SDS. (Circ J 2016; 80: 2047-2049).

Anatomic connections of the diaphragm influence of respiration on the body system

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Bordoni B

2013-07-01

Full Text Available Bruno Bordoni,1 Emiliano Zanier2 1Rehabilitation Cardiology Institute of Hospitalization and Care with Scientific Address, S Maria Nascente Don Carlo Gnocchi Foundation, 2EdiAcademy, Milano, Italy Abstract: The article explains the scientific reasons for the diaphragm muscle being an important crossroads for information involving the entire body. The diaphragm muscle extends from the trigeminal system to the pelvic floor, passing from the thoracic diaphragm to the floor of the mouth. Like many structures in the human body, the diaphragm muscle has more than one function, and has links throughout the body, and provides the network necessary for breathing. To assess and treat this muscle effectively, it is necessary to be aware of its anatomic, fascial, and neurologic complexity in the control of breathing. The patient is never a symptom localized, but a system that adapts to a corporeal dysfunction. Keywords: diaphragm, fascia, phrenic nerve, vagus nerve, pelvis

Diaphragm atrophy and weakness in the absence of mitochondrial dysfunction in the critically Ill

NARCIS (Netherlands)

Van den Berg, Marloes; Hooijman, Pleuni E.; Beishuizen, Albertus; De Waard, Monique C.; Paul, Marinus A.; Hartemink, Koen J.; Van Hees, Hieronymus W.H.; Lawlor, Michael W.; Brocca, Lorenza; Bottinelli, Roberto; Pellegrino, Maria A.; Stienen, Ger J.M.; Heunks, Leo M.A.; Wüst, Rob C.I.; Ottenheijm, Coen A.C.

2017-01-01

Rationale: The clinical significance of diaphragm weakness in critically ill patients is evident: it prolongs ventilator dependency and increases morbidity, duration of hospital stay, and health care costs. The mechanisms underlying diaphragm weakness are unknown, but might include mitochondrial

Fully automatic algorithm for segmenting full human diaphragm in non-contrast CT Images

Science.gov (United States)

Karami, Elham; Gaede, Stewart; Lee, Ting-Yim; Samani, Abbas

2015-03-01

The diaphragm is a sheet of muscle which separates the thorax from the abdomen and it acts as the most important muscle of the respiratory system. As such, an accurate segmentation of the diaphragm, not only provides key information for functional analysis of the respiratory system, but also can be used for locating other abdominal organs such as the liver. However, diaphragm segmentation is extremely challenging in non-contrast CT images due to the diaphragm's similar appearance to other abdominal organs. In this paper, we present a fully automatic algorithm for diaphragm segmentation in non-contrast CT images. The method is mainly based on a priori knowledge about the human diaphragm anatomy. The diaphragm domes are in contact with the lungs and the heart while its circumference runs along the lumbar vertebrae of the spine as well as the inferior border of the ribs and sternum. As such, the diaphragm can be delineated by segmentation of these organs followed by connecting relevant parts of their outline properly. More specifically, the bottom surface of the lungs and heart, the spine borders and the ribs are delineated, leading to a set of scattered points which represent the diaphragm's geometry. Next, a B-spline filter is used to find the smoothest surface which pass through these points. This algorithm was tested on a noncontrast CT image of a lung cancer patient. The results indicate that there is an average Hausdorff distance of 2.96 mm between the automatic and manually segmented diaphragms which implies a favourable accuracy.

Evaluation of Effective Diaphragm Area for Pneumatic Actuator

International Nuclear Information System (INIS)

Ryu, Hogeun; Han, Bongsub; Seon, Juhyoung

2016-01-01

The purpose of this study is to develop a methodology to calculate the exact effective diaphragm area using the results of diagnostic test to be performed in the evaluation of air operated valve performance. By using this developed methodology in pneumatic actuator performance evaluation, it can be reduce the possible errors arising from effective diaphragm area in the evaluation of performance of air operated valves. The performance assessment for the operability and structural integrity of air operated valves for the domestic nuclear power plant is in progress. One of the important parameters that determine the performance of the air operated valves is the effective diaphragm area of diaphragm type actuator. The effective diaphragm area is the actual area which the air pressure acting on the diaphragm. In general, the effective diaphragm area used for the performance evaluation of pneumatic actuator is provided by the manufacture or the actuator drawing. Flat type diaphragm was showed the difference between the measured value of EDA and the manufacture’s value, in the case of convoluted type diaphragm has showed that the measured value of EDA and manufacture’s value is almost the same. When evaluate a performance of a diaphragm actuator, accurate EDA is to be used because it is an important variable affecting the actuator performance. Particularly in the case of flat type diaphragm which EDA is changed in accordance with the stroke position, by using the EDA evaluation methodology developed in this study to minimize a possible error due to EDA when evaluating the performance of the air actuator

Evaluation of Effective Diaphragm Area for Pneumatic Actuator

Energy Technology Data Exchange (ETDEWEB)

Ryu, Hogeun; Han, Bongsub; Seon, Juhyoung [SOOSAN INDUSTRIES, Seoul (Korea, Republic of)

2016-10-15

The purpose of this study is to develop a methodology to calculate the exact effective diaphragm area using the results of diagnostic test to be performed in the evaluation of air operated valve performance. By using this developed methodology in pneumatic actuator performance evaluation, it can be reduce the possible errors arising from effective diaphragm area in the evaluation of performance of air operated valves. The performance assessment for the operability and structural integrity of air operated valves for the domestic nuclear power plant is in progress. One of the important parameters that determine the performance of the air operated valves is the effective diaphragm area of diaphragm type actuator. The effective diaphragm area is the actual area which the air pressure acting on the diaphragm. In general, the effective diaphragm area used for the performance evaluation of pneumatic actuator is provided by the manufacture or the actuator drawing. Flat type diaphragm was showed the difference between the measured value of EDA and the manufacture’s value, in the case of convoluted type diaphragm has showed that the measured value of EDA and manufacture’s value is almost the same. When evaluate a performance of a diaphragm actuator, accurate EDA is to be used because it is an important variable affecting the actuator performance. Particularly in the case of flat type diaphragm which EDA is changed in accordance with the stroke position, by using the EDA evaluation methodology developed in this study to minimize a possible error due to EDA when evaluating the performance of the air actuator.

Corneal confocal microscopy and dry eye findings in contact lens discomfort patients.

Science.gov (United States)

Dogan, Aysun Sanal; Gurdal, Canan; Arslan, Nese

2018-02-01

To evaluate the corneal confocal microscopy and dry eye findings in patients with contact lens discomfort. The study included 3 groups of participants: Contact lens wearers using silicone hydrogel soft contact lenses who are symptomatic (CLD, n=15) or asymptomatic (ACL, n=11) and non-wearers as controls (n=14). Duration of contact lens wear, Ocular Surface Disease Index (OSDI) questionnaire responses, fluorescein tear break-uptime (FBUT), and corneal confocal microscopy findings were recorded. Mean age was 25.7±8.2 years and male/female ratio was 7/33. Demographic findings were similar regarding the groups. CLD patients had a longer lens use history than ACL (median 5 vs 2 years, pCLD group than ACL or controls (pCLD group, compared to controls and ACL (pCLD group compared to controls but similar to ACL (pCLD group than the ACL (p=0.014). Patients with CLD had been wearing contact lenses for longer than those without symptoms. OSDI and FBUT scores were worse in CLD patients. In contact lens discomfort patients, there were increased dendritiform cells, indicating intensified inflammatory status of the cornea. Copyright © 2017 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Phacoemulsification and intraocular lens implantation in patients with oculocutaneous albinism.

Science.gov (United States)

Dávila, Pedro J; Ulloa-Padilla, Jan P; Izquierdo, Natalio J

2017-01-01

To evaluate the benefits of phacoemulsification and intraocular lens implantation in patients with oculocutaneous albinism (OCA). The charts of 195 patients with OCA who visited a local eye clinic were reviewed. All of these patients had genetic linkage analysis to establish OCA type. Frequencies and Paired t-test analysis were determined. Of the 195 patients, nine (4.6%) underwent clear cornea phacoemulsification with intraocular lens implantation. Seven of the nine patients with OCA had the Hermansky-Pudlak (HPS) type 1; two had OCA type 1. Pre-operative BCVA of all eyes ranged from 1.0 to 2.3 logMAR with a mean of 1.42 logMAR and a standard deviation of 0.41 logMAR. Post-operative BCVA of all eyes ranged from 1.0 to 1.30 logMAR with a mean of 1.04 logMAR and a standard deviation of 0.10 logMAR. BCVA improved after phacoemulsification surgery and intraocular lens implantation (p = 0.002). Pre-operative astigmatism of all eyes ranged from +0.50 to +5.75 with a mean of +2.25 and a standard deviation of +2.40. Post-operative astigmatism of all eyes ranged from +0.50 to +2.00 with a mean of +1.23 and a standard deviation of +0.42. Astigmatism improved after phacoemulsification surgery and intraocular lens implantation (p = 0.05). Nine patients with OCA who underwent phacoemulsification and intraocular lens implant experienced improved visual acuity and reduced astigmatism post-operatively. These results suggest cataract surgery may improve vision and refractive errors, and thus quality of life, in patients with albinism.

Identifying decreased diaphragmatic mobility and diaphragm thickening in interstitial lung disease: the utility of ultrasound imaging

Science.gov (United States)

Santana, Pauliane Vieira; Prina, Elena; Albuquerque, André Luis Pereira; Carvalho, Carlos Roberto Ribeiro; Caruso, Pedro

2016-01-01

Objective: To investigate the applicability of ultrasound imaging of the diaphragm in interstitial lung disease (ILD). Methods: Using ultrasound, we compared ILD patients and healthy volunteers (controls) in terms of diaphragmatic mobility during quiet and deep breathing; diaphragm thickness at functional residual capacity (FRC) and at total lung capacity (TLC); and the thickening fraction (TF, proportional diaphragm thickening from FRC to TLC). We also evaluated correlations between diaphragmatic dysfunction and lung function variables. Results: Between the ILD patients (n = 40) and the controls (n = 16), mean diaphragmatic mobility was comparable during quiet breathing, although it was significantly lower in the patients during deep breathing (4.5 ± 1.7 cm vs. 7.6 ± 1.4 cm; p < 0.01). The patients showed greater diaphragm thickness at FRC (p = 0.05), although, due to lower diaphragm thickness at TLC, they also showed a lower TF (p < 0.01). The FVC as a percentage of the predicted value (FVC%) correlated with diaphragmatic mobility (r = 0.73; p < 0.01), and an FVC% cut-off value of < 60% presented high sensitivity (92%) and specificity (81%) for indentifying decreased diaphragmatic mobility. Conclusions: Using ultrasound, we were able to show that diaphragmatic mobility and the TF were lower in ILD patients than in healthy controls, despite the greater diaphragm thickness at FRC in the former. Diaphragmatic mobility correlated with ILD functional severity, and an FVC% cut-off value of < 60% was found to be highly accurate for indentifying diaphragmatic dysfunction on ultrasound. PMID:27167428

Phacoemulsification using iris hooks and scleral fixation of the intraocular lens in patients with secondary glaucoma associated with lens subluxation.

Science.gov (United States)

Ma, K T; Lee, H K; Seong, G J; Kim, C Y

2008-09-01

We described the techniques and results of phacoemulsification using iris hook and scleral fixation of intraocular lens (IOL) in patients with secondary glaucoma associated with lens subluxation. Eight eyes of seven patients with secondary glaucoma associated with lens dislocation, who had undergone the surgery, were retrospectively reviewed. At a mean of 23.5 months+/-13.6 (SD) after the surgery, the mean best-corrected visual acuity improved from 0.24+/-0.21 to 0.83+/-0.3, and mean intraocular pressure (IOP) was changed from 38.4+/-11.4 to 15.5+/-1.8 mmHg at the final examination. There were no vitreoretinal complications except cystoid macular oedema in one eye. The technique appears to be safe and effective in terms of visual rehabilitation and controlling IOP in patients with secondary glaucoma associated with lens subluxation.

Ocular Surface Temperature During Scleral Lens Wearing in Patients With Keratoconus.

Science.gov (United States)

Carracedo, Gonzalo; Wang, Zicheng; Serramito-Blanco, Maria; Martin-Gil, Alba; Carballo-Alvarez, Jesús; Pintor, Jesús

2017-11-01

To evaluate the ocular surface temperature using an infrared thermography camera before and after wearing scleral lens in patients with keratoconus and correlate these results with the tear production and stability. A pilot, experimental, short-term study has been performed. Twenty-six patients with keratoconus (36.95±8.95 years) participated voluntarily in the study. The sample was divided into two groups: patients with intrastromal corneal ring (KC-ICRS group) and patients without ICRS (KC group). Schirmer test, tear breakup time (TBUT), and ocular surface temperature in the conjunctiva, limbus, and cornea were evaluated before and after wearing a scleral lens. The patients wore the scleral lenses from 6 to 9 hours with average of 7.59±0.73 hours. No significant changes in Schirmer test and TBUT were found for both groups. No temperature differences were found between the KC-ICRS and the KC groups for all zones evaluated. There was a slight, but statistically significant, increase in the inferior cornea, temporal limbus, and nasal conjunctival temperature for KC-ICRS group and temporal limbus temperature decreasing for the KC group after wearing scleral lens (Ptemperature was statistically higher than the central cornea for both groups before and after scleral lenses wearing (Pperipheral cornea was found. No statistically significant differences in the central corneal temperature were found between the groups after scleral lens wearing (P>0.05). Scleral contact lens seems not to modify the ocular surface temperature despite the presence of the tear film stagnation under the lens.

Simple and effective solution for diaphragm pacing by that uses the transvenous femoral approach in a patient treated with cardiac resynchronization-defibrillator therapy: The wrapping method

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Ahmet Taha Alper, Prof.

2017-08-01

Full Text Available The use of cardiac resynchronization therapy (CRT has become widespread in patients with heart failure who meet the criteria for implantation. Coronary sinus lead positioning is important to provide the intended biventricular stimulation. Diaphragm pacing is a lead-related complication which occurs secondary to phrenic nerve stimulation. We present the case of a 58-year-old male patient who had diaphragm pacing after CRT with defibrillator implantation. The complication was resolved by using the transvenous femoral approach with the wrapping method.

Treatment, material, care, and patient-related factors in contact lens-related dry eye.

Science.gov (United States)

Ramamoorthy, Padmapriya; Sinnott, Loraine T; Nichols, Jason J

2008-08-01

To examine the effect of general contact lens and material characteristics, care solutions, treatment, and patient-related factors on contact lens-related dry eye. The data were derived from the Contact Lens and Dry Eye Study, designed as a cross-sectional and nested case-control study including 360 subjects. In separate statistical models, logistic regression was used to examine general contact lens characteristics, specific hydrogel lens materials, care solutions, and patient-related factors associated with dry eye status (controlled for age, gender, and current treatments). Several factors were significantly associated with dry eye, including treatment factors such as a recent contact lens refitting (odds ratios [OR] = 5.75, 95% confidence intervals [CI] = 2.14 to 15.46) and use of artificial tears/rewetting drops (OR = 1.09, 95% CI = 1.02 to 1.16), in addition, currently worn materials including Food and Drug Administration (FDA) group II (OR = 2.98, 95% CI = 1.14 to 6.19) and IV (OR = 1.87, 95% CI = 1.08 to 3.24). Significant patient-related factors included decreased overall satisfaction (OR = 3.57, 95% CI = 2.08 to 5.88,), dry eye in the absence of contact lens wear (OR = 6.54, 95% CI = 2.57 to 16.62), reduced daily lens wear duration (OR = 1.16, 95% CI = 1.06 to 1.26), and reduced ability to wear lenses as long as desired (OR = 2.44, 95% CI = 1.30 to 4.54). Care solutions were not associated with contact lens-related dry eye. The strong association of common treatment factors with dry eye status in contact lens wearers suggests that these treatments are not entirely effective. The use of high water content materials was strongly related to dry eye in lens wearers, whereas care solutions were not. Contact lens-related dry eye was also associated with several patient-related factors such as greater ocular discomfort (without lenses), dissatisfaction, and inability to wear lenses for desired durations.

Verification on reliability of diaphragm seal

International Nuclear Information System (INIS)

Ide, Hiroshi; Sakuta, Yoshiyuki; Hanawa, Yoshio; Tsuji, Tomoyuki; Tsuboi, Kazuaki; Nagao, Yoshiharu; Miyazawa, Masataka

2009-06-01

The main body of the JMTR is composed of reactor pressure vessel, core and reactor pool. At the bottom of the reactor pool, the Diaphragm-seal (2.6m outer diameter, 2m inner diameter, thickness 1.5mm) of the JMTR made of stainless steel is installed to prevent the water leak of the reactor pool and to absorb the expansion of the reactor pressure vessel due to pressure and temperature changes. In the long-term maintenance plans drawn up in 2004, it is required that the visual inspection for the diaphragm-seal should be carried out in 2007 and that the inspection should be carried out every around five-year. Therefore, prior to the refurbishment of the JMTR, the inspection device which is a deposition-collection apparatus with underwater-camera was developed, and the visual inspection was carried out to confirm the soundness of the diaphragm-seal. As a result, harmful flaws and/or corrosions were not inspected in the visual inspection, and the soundness of the diaphragm seal was confirmed. In future, the long-term integrity of the diaphragm-seal will could be achieved by conducting the periodic inspection. (author)

Movement of the diaphragm during radiation treatment

International Nuclear Information System (INIS)

Nishioka, Masayuki; Fujioka, Tomio; Sakurai, Makoto; Nakajima, Toshifumi; Onoyama, Yasuto.

1991-01-01

Movement of the target volume during the exposure to radiation results in decreased accuracy in radiotherapy. We carried out the quantitative evaluation of the movement of the diaphragm during the radiation therapy. Seventy seven patients, who received radiation therapy for lung cancer from December 1988 to February 1990 at the Osaka-prefectural Habikino Hospital, were studied. The movement was recorded with a sonoprinter at the time of treatment planning for radiotherapy, and the length of movement was evaluated at 6 points on the diaphragm. In a study of 402 points in 77 patients, the average movement was 12 mm, and the maximum movement was 40 mm. At the 17% of the points, the movement exceeded 20 mm. The largest movement was observed at the outer point of the right lung. Movement was greater in men than in women. Performance status was not related to the degree of movement. We concluded that in chest and abdominal irradiation, movement caused by respiration is not negligible, and synchronized radiotherapy should be developed in the future. (author)

To detect anomalies in diaphragm walls

NARCIS (Netherlands)

Spruit, R.

2015-01-01

Diaphragm walls are potentially ideal retaining walls for deep excavations in densely built-up areas, as they cause no vibrations during their construction and provide structural elements with high strength and stiffness. In the recent past, however, several projects using diaphragm walls as soil

Visualization of the diaphragm muscle with ultrasound improves diagnostic accuracy of phrenic nerve conduction studies.

Science.gov (United States)

Johnson, Nicholas E; Utz, Michael; Patrick, Erica; Rheinwald, Nicole; Downs, Marlene; Dilek, Nuran; Dogra, Vikram; Logigian, Eric L

2014-05-01

Evaluation of phrenic neuropathy (PN) with phrenic nerve conduction studies (PNCS) is associated with false negatives. Visualization of diaphragmatic muscle twitch with diaphragm ultrasound (DUS) when performing PNCS may help to solve this problem. We performed bilateral, simultaneous DUS-PNCS in 10 healthy adults and 12 patients with PN. The amplitude of the diaphragm compound muscle action potential (CMAP) (on PNCS) and twitch (on DUS) was calculated. Control subjects had phrenic CMAP (on PCNS). In the 12 patients with PN, 12 phrenic neuropathies were detected. Three of these patients had either significant side-to-side asymmetry or absolute reduction in diaphragm movement that was not detected with PNCS. There were no cases in which the PNCS showed an abnormality but the DUS did not. The addition of DUS to PNCS enhances diagnostic accuracy in PN. Copyright © 2013 Wiley Periodicals, Inc.

WE-G-18C-06: Is Diaphragm Motion a Good Surrogate for Liver Tumor Motion?

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Yang, J [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); School of Information Science and Engineering, Shandong University, Jinan, Shandong (China); Cai, J; Zheng, C; Czito, B; Palta, M; Yin, F [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Wang, H [School of Information Science and Engineering, Shandong University, Jinan, Shandong (China); Bashir, M [Department of Radiology, Duke University Medical Center, Durham, NC (United States)

2014-06-15

Purpose: To investigate whether diaphragm motion is a good surrogate for liver tumor motion by comparing their motion trajectories obtained from cine-MRI. Methods: Fourteen patients with hepatocellular carcinoma (10/14) or liver metastases (4/14) undergoing radiation therapy were included in this study. All patients underwent single-slice 2D cine-MRI simulations across the center of the tumor in three orthogonal planes. Tumor and diaphragm motion trajectories in the superior-inferior (SI), anteriorposterior (AP), and medial-lateral (ML) directions were obtained using the normalized cross-correlation based tracking technique. Agreement between tumor and diaphragm motions was assessed by calculating the phase difference percentage (PDP), intra-class correlation coefficient (ICC), Bland-Altman analysis (Diffs) and paired t-test. The distance (D) between tumor and tracked diaphragm area was analyzed to understand its impact on the correlation between tumor and diaphragm motions. Results: Of all patients, the means (±standard deviations) of PDP were 7.1 (±1.1)%, 4.5 (±0.5)% and 17.5 (±4.5)% in the SI, AP and ML directions, respectively. The means of ICC were 0.98 (±0.02), 0.97 (±0.02), and 0.08 (±0.06) in the SI, AP and ML directions, respectively. The Diffs were 2.8 (±1.4) mm, 2.4 (±1.1) mm, and 2.2 (±0.5) mm in the SI, AP and ML directions, respectively. The p-values derived from the paired t-test were < 0.02 in SI and AP directions, whereas were > 0.58 in ML direction primarily due to the small motion in ML direction. Tumor and diaphragmatic motion had high concordance when the distance between the tumor and tracked diaphragm areas was small. Conclusion: Preliminary results showed that liver tumor motion had good correlations with diaphragm motion in the SI and AP directions, indicating diaphragm motion in the SI and AP directions could potentially be a reliable surrogate for liver tumor motion. NIH (1R21CA165384-01A1), Golfers Against Cancer (GAC

Materials for Slack Diaphragms

Science.gov (United States)

Puschmann, Traute

1940-01-01

This report deals with systematic experiments carried out on five diaphragm materials with different pretreatment, for the purpose of ascertaining the suitability of such materials for slack diaphragms. The relationship of deflection and load, temperature and moisture, was recorded. Of the explored materials, synthetic leather, balloon cloth, goldbeaters skin, Igelit and Buna, synthetic leather treated with castor oil is the most suitable material for the small pressure range required. Balloon cloth is nearly as good, while goldbeaters skin, Igelit and Buna were found to be below the required standards.

Post-lens tear turbidity and visual quality after scleral lens wear.

Science.gov (United States)

Carracedo, Gonzalo; Serramito-Blanco, Maria; Martin-Gil, Alba; Wang, Zicheng; Rodriguez-Pomar, Candela; Pintor, Jesús

2017-11-01

The aim was to evaluate the turbidity and thickness of the post-lens tear layer and its effect on visual quality in patients with keratoconus after the beginning of lens wear and before lens removal at the end of eight hours. Twenty-six patients with keratoconus (aged 36.95 ± 8.95 years) participated voluntarily in the study. The sample was divided into two groups: patients with intrastromal corneal ring (ICRS group) and patients without ICRS (KC group). Distance visual acuity (VA), contrast sensitivity, pachymetry, post-lens tear layer height and post-lens tear layer turbidity (percentage area occupied and number of particles per mm 2 ) were evaluated with optical coherence tomography before and after wearing a scleral lens. A significant increase of turbidity was found in all groups assessed (p turbidity parameters with distance VA but no correlation between turbidity and post-lens tear layer thickness at the beginning was found (p > 0.05). A strong correlation in all groups between the post-lens tear layer at the beginning and differences of tear layer thickness between two measures was also found (p turbidity. © 2017 Optometry Australia.

Phrenic Nerve Reconstruction and Bilateral Diaphragm Plication After Lobectomy.

Science.gov (United States)

Shinohara, Shuichi; Yamada, Tetsu; Ueda, Mitsuhiro; Ishinagi, Hiroyoshi; Matsuoka, Takahisa; Nagai, Shinjiro; Matsuoka, Katsunari; Miyamoto, Yoshihiro

2017-07-01

A 49-year-old man with left phrenic nerve paralysis caused by mediastinal tumor resection 28 years earlier was found to have a nodule in the right upper lobe. The right phrenic nerve was severed during right upper lobectomy but was reconstructed along with bilateral plication of the diaphragm. The patient was weaned from the ventilator during the daytime on postoperative day 13 and was discharged home on postoperative day 48. Three months postoperatively, chest fluoroscopic imaging showed recovery of movement of the right diaphragm. Nerve conduction studies showed improvement of function of the reconstructed right phrenic nerve. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Dexmedetomidine May Produce Extra Protective Effects on Sepsis-induced Diaphragm Injury

Directory of Open Access Journals (Sweden)

Jin Wu

2015-01-01

Full Text Available Objective: The objective was to evaluate the protective effects of dexmedetomidine (DEX, a selective agonist of α2-adrenergic receptor, on sepsis-induced diaphragm injury and the underlying molecular mechanisms. Data Sources: The data used in this review were mainly from PubMed articles published in English from 1990 to 2015. Study Selection: Clinical or basic research articles were selected mainly according to their level of relevance to this topic. Results: Sepsis could induce severe diaphragm dysfunction and exacerbate respiratory weakness. The mechanism of sepsis-induced diaphragm injury includes the increased inflammatory cytokines and excessive oxidative stress and superfluous production of nitric oxide (NO. DEX can reduce inflammatory cytokines, inhibit nuclear factor-kappaB signaling pathways, suppress the activation of caspase-3, furthermore decrease oxidative stress and inhibit NO synthase. On the basis of these mechanisms, DEX may result in a shorter period of mechanical ventilation in septic patients in clinical practice. Conclusions: Based on this current available evidence, DEX may produce extra protective effects on sepsis-induced diaphragm injury. Further direct evidence and more specific studies are still required to confirm these beneficial effects.

Progressive Diaphragm Atrophy in Pediatric Acute Respiratory Failure.

Science.gov (United States)

Glau, Christie L; Conlon, Thomas W; Himebauch, Adam S; Yehya, Nadir; Weiss, Scott L; Berg, Robert A; Nishisaki, Akira

2018-02-05

Diaphragm atrophy is associated with delayed weaning from mechanical ventilation and increased mortality in critically ill adults. We sought to test for the presence of diaphragm atrophy in children with acute respiratory failure. Prospective, observational study. Single-center tertiary noncardiac PICU in a children's hospital. Invasively ventilated children with acute respiratory failure. Diaphragm thickness at end-expiration and end-inspiration were serially measured by ultrasound in 56 patients (median age, 17 mo; interquartile range, 5.5-52), first within 36 hours of intubation and last preceding extubation. The median duration of mechanical ventilation was 140 hours (interquartile range, 83-201). At initial measurement, thickness at end-expiration was 2.0 mm (interquartile range, 1.8-2.5) and thickness at end-inspiration was 2.5 mm (interquartile range, 2-2.8). The change in thickness at end-expiration during mechanical ventilation between first and last measurement was -13.8% (interquartile range, -27.4% to 0%), with a -3.4% daily atrophy rate (interquartile range, -5.6 to 0%). Thickening fraction = ([thickness at end-inspiration - thickness at end-expiration]/thickness at end-inspiration) throughout the course of mechanical ventilation was linearly correlated with spontaneous breathing fraction (beta coefficient, 9.4; 95% CI, 4.2-14.7; p = 0.001). For children with a period of spontaneous breathing fraction less than 0.5 during mechanical ventilation, those with exposure to a continuous neuromuscular blockade infusion (n = 15) had a significantly larger decrease in thickness at end-expiration compared with children with low spontaneous breathing fraction who were not exposed to a neuromuscular blockade infusion (n = 18) (-16.4%, [interquartile range, -28.4% to -7.0%] vs -7.3%; [interquartile range, -10.9% to -0%]; p = 0.036). Diaphragm atrophy is present in children on mechanical ventilation for acute respiratory failure. Diaphragm contractility, measured as

Morphological and ultrastructural evaluation of the golden retriever muscular dystrophy trachea, lungs, and diaphragm muscle.

Science.gov (United States)

Lessa, Thais Borges; de Abreu, Dilayla Kelly; Rodrigues, Márcio Nogueira; Brólio, Marina Pandolphi; Miglino, Maria Angélica; Ambrósio, Carlos Eduardo

2014-11-01

Duchenne muscular dystrophy (DMD) is a genetic disease, characterized by atrophy and muscle weakness. The respiratory failure is a common cause of early death in patients with DMD. Golden retriever muscular dystrophy (GRMD) is a canine model which has been extensively used for many advances in therapeutics applications. As the patients with DMD, the GRMD frequently died from cardiac and respiratory failure. Observing the respiratory failure in DMD is one of the major causes of mortality we aimed to describe the morphological and ultrastructural data of trachea, lungs (conductive and respiratory portion of the system), and diaphragm muscle using histological and ultrastructural analysis. The diaphragm muscle showed discontinuous fibers architecture, with different diameter; a robust perimysium inflammatory infiltrate and some muscle cells displayed central nuclei. GRMD trachea and lungs presented collagen fibers and in addition, the GRMD lungs showed higher of levels collagen fibers that could limit the alveolar ducts and alveoli distension. Therefore, the most features observed were the collagen areas and fibrosis. We suggested in this study that the collagen remodeling in the trachea, lungs, and diaphragm muscle may increase fibrosis and affect the trachea, lungs, and diaphragm muscle function that can be a major cause of respiratory failure that occur in patients with DMD. © 2014 Wiley Periodicals, Inc.

Analytical model for an electrostatically actuated miniature diaphragm compressor

International Nuclear Information System (INIS)

Sathe, Abhijit A; Groll, Eckhard A; Garimella, Suresh V

2008-01-01

This paper presents a new analytical approach for quasi-static modeling of an electrostatically actuated diaphragm compressor that could be employed in a miniature scale refrigeration system. The compressor consists of a flexible circular diaphragm clamped at its circumference. A conformal chamber encloses the diaphragm completely. The membrane and the chamber surfaces are coated with metallic electrodes. A potential difference applied between the diaphragm and the chamber pulls the diaphragm toward the chamber surface progressively from the outer circumference toward the center. This zipping actuation reduces the volume available to the refrigerant gas, thereby increasing its pressure. A segmentation technique is proposed for analysis of the compressor by which the domain is divided into multiple segments for each of which the forces acting on the diaphragm are estimated. The pull-down voltage to completely zip each individual segment is thus obtained. The required voltage for obtaining a specific pressure rise in the chamber can thus be determined. Predictions from the model compare well with other simulation results from the literature, as well as to experimental measurements of the diaphragm displacement and chamber pressure rise in a custom-built setup

The Stress and Stiffness Analysis of Diaphragm

Directory of Open Access Journals (Sweden)

Qu Dongyue

2017-01-01

Full Text Available Diaphragm coupling with its simple structure, small size, high reliability, which can compensate for its input and output displacement deviation by its elastic deformation, is widely used in aerospace, marine, and chemical etc. This paper uses the ANSYS software and its APDL language to analysis the stress distribution when the diaphragm under the load of torque, axial deviation, centrifugal force, angular deviation and multiple loads. We find that the value of maximum stress usually appears in the outer or inner transition region and the axial deviation has a greater influence to the distribution of the stress. Based on above, we got three kinds of stiffness for axial, angular and torque, which the stiffness of diaphragm is nearly invariable. The results can be regard as an important reference for design and optimization of diaphragm coupling.

Compliance among soft contact lens wearers.

Science.gov (United States)

Kuzman, Tomislav; Kutija, Marija Barisić; Masnec, Sanja; Jandroković, Sonja; Mrazovac, Danijela; Jurisić, Darija; Skegro, Ivan; Kalauz, Miro; Kordić, Rajko

2014-12-01

Contact lens compliance is proven to be crucial for preventing lens wear-related complications because of the interdependence of the steps in lens care regime and their influence on lens system microbial contamination. Awareness of the patients' lens handling compliance as well as correct recognition of non-compliant behaviours is the basis for creating more targeted strategies for patient education. The aim of this study was to investigate compliance among soft contact lens (SCL) wearers in different aspects of lens care handling and wearing habits. In our research 50 asymptomatic lens wearers filled out a questionnaire containing demographic data, lens type, hygiene and wearing habits, lenses and lens care system replacement schedule and self-evaluation of contact lens handling hygiene. We established criteria of compliance according to available manufacturer's recommendations, prior literature and our clinical experience. Only 2 (4%) of patients were fully compliant SCL wearers. The most common non-compliant behaviours were insufficient lens solution soaking time (62%), followed by failure to daily exchange lens case solution and showering while wearing lenses. 44% of patients reported storing lenses in saline solution. Mean lens storage case replacement was 3.6 months, with up to 78% patients replacing lens case at least once in 3 months. Average grade in self evaluating level of compliance was very good (4 +/- 0.78) (from 1-poor level of hygiene to 5-great level of hygiene). Lens wearers who reported excessive daily lens wear and more than 10 years of lens wearing experience were also found to be less compliant with other lens system care procedures. (t = -2.99, df=47, p rate, self grading was relatively high. Therefore, these results indicate the need for patient education and encouragement of better lens wearing habits and all of the lens maintenance steps at each patient visit.

DiPALS: Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis - a randomised controlled trial.

Science.gov (United States)

McDermott, Christopher J; Bradburn, Mike J; Maguire, Chin; Cooper, Cindy L; Baird, Wendy O; Baxter, Susan K; Cohen, Judith; Cantrill, Hannah; Dixon, Simon; Ackroyd, Roger; Baudouin, Simon; Bentley, Andrew; Berrisford, Richard; Bianchi, Stephen; Bourke, Stephen C; Darlison, Roy; Ealing, John; Elliott, Mark; Fitzgerald, Patrick; Galloway, Simon; Hamdalla, Hisham; Hanemann, C Oliver; Hughes, Philip; Imam, Ibrahim; Karat, Dayalan; Leek, Roger; Maynard, Nick; Orrell, Richard W; Sarela, Abeezar; Stradling, John; Talbot, Kevin; Taylor, Lyn; Turner, Martin; Simonds, Anita K; Williams, Tim; Wedzicha, Wisia; Young, Carolyn; Shaw, Pamela J

2016-06-01

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease resulting in death, usually from respiratory failure, within 2-3 years of symptom onset. Non-invasive ventilation (NIV) is a treatment that when given to patients in respiratory failure leads to improved survival and quality of life. Diaphragm pacing (DP), using the NeuRx/4(®) diaphragm pacing system (DPS)™ (Synapse Biomedical, Oberlin, OH, USA), is a new technique that may offer additional or alternative benefits to patients with ALS who are in respiratory failure. The Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis (DiPALS) trial evaluated the effect of DP on survival over the study duration in patients with ALS with respiratory failure. The DiPALS trial was a multicentre, parallel-group, open-label, randomised controlled trial incorporating health economic analyses and a qualitative longitudinal substudy. Eligible participants had a diagnosis of ALS (ALS laboratory-supported probable, clinically probable or clinically definite according to the World Federation of Neurology revised El Escorial criteria), had been stabilised on riluzole for 30 days, were aged ≥ 18 years and were in respiratory failure. We planned to recruit 108 patients from seven UK-based specialist ALS or respiratory centres. Allocation was performed using 1 : 1 non-deterministic minimisation. Participants were randomised to either standard care (NIV alone) or standard care (NIV) plus DP using the NeuRX/4 DPS. The primary outcome was overall survival, defined as the time from randomisation to death from any cause. Secondary outcomes were patient quality of life [assessed by European Quality of Life-5 Dimensions, three levels (EQ-5D-3L), Short Form questionnaire-36 items and Sleep Apnoea Quality of Life Index questionnaire]; carer quality of life (EQ-5D-3L and Caregiver Burden Inventory); cost-utility analysis and health-care resource use; tolerability and adverse events. Acceptability and attitudes to

Fluid structure interaction in piston diaphragm pumps

NARCIS (Netherlands)

van Rijswick, R.J.A.

2017-01-01

Piston diaphragm pumps are used world-wide to transport abrasive and/or aggressive slurries against high discharge pressures in the mining, mineral processing and power industries. Limitation of excessive deformation of the diaphragm is of utmost importance for eliminating fatigue failures of the

Efficient generation of lens progenitor cells from cataract patient-specific induced pluripotent stem cells.

Directory of Open Access Journals (Sweden)

Xiaodi Qiu

Full Text Available The development of a technique to induce the transformation of somatic cells to a pluripotent state via the ectopic expression of defined transcription factors was a transformational event in the field of regenerative medicine. The development of this technique also impacted ophthalmology, as patient-specific induced pluripotent stemcells (iPSCs may be useful resources for some ophthalmological diseases. The lens is a key refractive element in the eye that focuses images of the visual world onto the retina. To establish a new model for drug screening to treat lens diseases and investigating lens aging and development, we examined whether human lens epithelial cells (HLECs could be induced into iPSCs and if lens-specific differentiation of these cells could be achieved under defined chemical conditions. We first efficiently reprogrammed HLECs from age-related cataract patients to iPSCs with OCT-4, SOX-2, and KLF-4. The resulting HLEC-derived iPS (HLE-iPS colonies were indistinguishable from human ES cells with respect to morphology, gene expression, pluripotent marker expression and their ability to generate all embryonic germ-cell layers. Next, we performed a 3-step induction procedure: HLE-iPS cells were differentiated into large numbers of lens progenitor-like cells with defined factors (Noggin, BMP and FGF2, and we determined that these cells expressed lens-specific markers (PAX6, SOX2, SIX3, CRYAB, CRYAA, BFSP1, and MIP. In addition, HLE-iPS-derived lens cells exhibited reduced expression of epithelial mesenchymal transition (EMT markers compared with human embryonic stem cells (hESCs and fibroblast-derived iPSCs. Our study describes a highly efficient procedure for generating lens progenitor cells from cataract patient HLEC-derived iPSCs. These patient-derived pluripotent cells provide a valuable model for studying the developmental and molecular biological mechanisms that underlie cell determination in lens development and cataract

Diaphragms obtained by radiochemical grafting in PTFE

International Nuclear Information System (INIS)

Nenner, T.; Fahrasmane, A.

1984-01-01

Diaphragms for alkaline water electrolysis are prepared by radiochemical grafting of PTFE fabric with styrene, which is later on sulfonated, or with acrylic acid. The diaphragms obtained are mechanically resistant to potash at temperatures up to 200 0 C, but show some degrafting, which limits the lifetime. The sulfonated styrene group has been found to be more stable in electrolysis than the acrylic acid. In both cases, the incorporation of a cross-linking agent like divinyl benzene improves the lifetime of the diaphragms. Electrolysis during 500 hours at 120 0 C and 10 kAm 2 could be performed. (author)

SU-G-BRA-08: Diaphragm Motion Tracking Based On KV CBCT Projections with a Constrained Linear Regression Optimization

Energy Technology Data Exchange (ETDEWEB)

Wei, J [City College of New York, New York, NY (United States); Chao, M [The Mount Sinai Medical Center, New York, NY (United States)

2016-06-15

Purpose: To develop a novel strategy to extract the respiratory motion of the thoracic diaphragm from kilovoltage cone beam computed tomography (CBCT) projections by a constrained linear regression optimization technique. Methods: A parabolic function was identified as the geometric model and was employed to fit the shape of the diaphragm on the CBCT projections. The search was initialized by five manually placed seeds on a pre-selected projection image. Temporal redundancies, the enabling phenomenology in video compression and encoding techniques, inherent in the dynamic properties of the diaphragm motion together with the geometrical shape of the diaphragm boundary and the associated algebraic constraint that significantly reduced the searching space of viable parabolic parameters was integrated, which can be effectively optimized by a constrained linear regression approach on the subsequent projections. The innovative algebraic constraints stipulating the kinetic range of the motion and the spatial constraint preventing any unphysical deviations was able to obtain the optimal contour of the diaphragm with minimal initialization. The algorithm was assessed by a fluoroscopic movie acquired at anteriorposterior fixed direction and kilovoltage CBCT projection image sets from four lung and two liver patients. The automatic tracing by the proposed algorithm and manual tracking by a human operator were compared in both space and frequency domains. Results: The error between the estimated and manual detections for the fluoroscopic movie was 0.54mm with standard deviation (SD) of 0.45mm, while the average error for the CBCT projections was 0.79mm with SD of 0.64mm for all enrolled patients. The submillimeter accuracy outcome exhibits the promise of the proposed constrained linear regression approach to track the diaphragm motion on rotational projection images. Conclusion: The new algorithm will provide a potential solution to rendering diaphragm motion and ultimately

SU-G-BRA-08: Diaphragm Motion Tracking Based On KV CBCT Projections with a Constrained Linear Regression Optimization

International Nuclear Information System (INIS)

Wei, J; Chao, M

2016-01-01

Purpose: To develop a novel strategy to extract the respiratory motion of the thoracic diaphragm from kilovoltage cone beam computed tomography (CBCT) projections by a constrained linear regression optimization technique. Methods: A parabolic function was identified as the geometric model and was employed to fit the shape of the diaphragm on the CBCT projections. The search was initialized by five manually placed seeds on a pre-selected projection image. Temporal redundancies, the enabling phenomenology in video compression and encoding techniques, inherent in the dynamic properties of the diaphragm motion together with the geometrical shape of the diaphragm boundary and the associated algebraic constraint that significantly reduced the searching space of viable parabolic parameters was integrated, which can be effectively optimized by a constrained linear regression approach on the subsequent projections. The innovative algebraic constraints stipulating the kinetic range of the motion and the spatial constraint preventing any unphysical deviations was able to obtain the optimal contour of the diaphragm with minimal initialization. The algorithm was assessed by a fluoroscopic movie acquired at anteriorposterior fixed direction and kilovoltage CBCT projection image sets from four lung and two liver patients. The automatic tracing by the proposed algorithm and manual tracking by a human operator were compared in both space and frequency domains. Results: The error between the estimated and manual detections for the fluoroscopic movie was 0.54mm with standard deviation (SD) of 0.45mm, while the average error for the CBCT projections was 0.79mm with SD of 0.64mm for all enrolled patients. The submillimeter accuracy outcome exhibits the promise of the proposed constrained linear regression approach to track the diaphragm motion on rotational projection images. Conclusion: The new algorithm will provide a potential solution to rendering diaphragm motion and ultimately

Comparison of clinical utility between diaphragm excursion and thickening change using ultrasonography to predict extubation success

Science.gov (United States)

Yoo, Jung-Wan; Lee, Seung Jun; Lee, Jong Deog; Kim, Ho Cheol

2018-01-01

Background/Aims Both diaphragmatic excursion and change in muscle thickening are measured using ultrasonography (US) to assess diaphragm function and mechanical ventilation weaning outcomes. However, which parameter can better predict successful extubation remains to be determined. The aim of this study was to compare the clinical utility of these two diaphragmatic parameters to predict extubation success. Methods This study included patients subjected to extubation trial in the medical or surgical intensive care unit of a university-affiliated hospital from May 2015 through February 2016. Diaphragm excursion and percent of thickening change (Δtdi%) were measured using US within 24 hours before extubation. Results Sixty patients were included, and 78.3% (47/60) of these patients were successfully extubated, whereas 21.7% (13/60) were not. The median degree of excursion was greater in patients with extubation success than in those with extubation failure (1.65 cm vs. 0.8 cm, p success had a greater Δtdi% than those with extubation failure (42.1% vs. 22.5%, p = 0.03). The areas under the receiver operating curve for excursion and Δtdi% were 0.836 (95% confidence interval [CI], 0.717 to 0.919) and 0.698 (95% CI, 0.566 to 0.810), respectively (p = 0.017). Conclusions Diaphragm excursion seems more accurate than a change in the diaphragm thickness to predict extubation success. PMID:29050461

Analytical investigation of bidirectional ductile diaphragms in multi-span bridges

Science.gov (United States)

Wei, Xiaone; Bruneau, Michel

2018-04-01

In the AASHTO Guide Specifications for Seismic Bridge Design Provisions, ductile diaphragms are identified as Permissible Earthquake-Resisting Elements (EREs), designed to help resist seismic loads applied in the transverse direction of bridges. When adding longitudinal ductile diaphragms, a bidirectional ductile diaphragm system is created that can address seismic excitations acting along both the bridge's longitudinal and transverse axes. This paper investigates bidirectional ductile diaphragms with Buckling Restrained Braces (BRBs) in straight multi-span bridge with simply supported floating spans. The flexibility of the substructures in the transverse and longitudinal direction of the bridge is considered. Design procedures for the bidirectional ductile diaphragms are first proposed. An analytical model of the example bridge with bidirectional ductile diaphragms, designed based on the proposed methodology, is then built in SAP2000. Pushover and nonlinear time history analyses are performed on the bridge model, and corresponding results are presented. The effect of changing the longitudinal stiffness of the bidirectional ductile diaphragms in the end spans connecting to the abutment is also investigated, in order to better understand the impact on the bridge's dynamic performance.

Bending-Induced Giant Polarization in Ferroelectric MEMS Diaphragm

KAUST Repository

Wang, Zhihong

2016-09-09

The polarization induced by the strain gradient, i.e. the flexoelectric effect, has been observed in a micromachined Pb(Zr0.52Ti0.48)O3 (PZT) diaphragms. Applying air pressure to bend a flat diaphragm which initially does not exhibit any electromechanical coupling can induce a resonance peak in its impedance spectrum. This result supposes that bending, thus the strain gradient in the diaphragm causes polarization in PZT film. We also investigated the switching behaviors of the polarization in response to an external electric field in a bent diaphragm and further quantified the polarization induced by the strain gradient. The effective flexoelectric coefficient of the PZT film has been calculated as large as 2.0 × 10−4 C/m. A giant flexoelectric polarization of the order of 1 μC/cm2 was characterized which is of the same order of magnitude as the normal remnant ferroelectric polarization of PZT film. The suggested explanation for the giant polarization is the large strain gradient in the diaphragm and the strain gradient induced reorientation of the polar nanodomains.

Comparison of clear lens extraction and collamer lens implantation in high myopia

Directory of Open Access Journals (Sweden)

Ahmed M Emarah

2010-05-01

Full Text Available Ahmed M Emarah, Mostafa A El-Helw, Hazem M YassinCairo University, Cairo, EgyptAim: To compare the outcomes of clear lens extraction and collamer lens implantation in high myopia.Patients and methods: Myopic patients younger than 40 years old with more than 12 diopters of myopia or who were not fit for laser-assisted in situ keratomileusis were included. Group 1 comprised patients undergoing clear lens extraction and Group 2 patients received the Visian implantable collamer lens. Outcome and complications were evaluated.Results: Postoperative best corrected visual acuity was -0.61 ± 0.18 in Group 1 and 0.79 ± 0.16 in Group 2. In Group 1, 71.4% achieved a postoperative uncorrected visual acuity better than the preoperative best corrected visual acuity, while only 51.8% patients achieved this in Group 2. Intraocular pressure decreased by 12.55% in Group 1, and increased by 15.11% in Group 2. Corneal endothelial cell density decreased by 4.47% in Group 1 and decreased by 5.67% in Group 2. Posterior capsule opacification occurred in Group 1. In Group 2, lens opacification occurred in 11.11%, significant pigment dispersion in 3.7%, and pupillary block glaucoma in 3.7%.Conclusion: Clear lens extraction presents less of a financial load up front, and less likelihood of the need for a secondary intervention in the future. Clear lens extraction is a more viable solution in developing countries with limited financial resources.Keywords: clear lens extraction, implantable collamer lens, myopia

Fluid structure interaction in piston diaphragm pumps

NARCIS (Netherlands)

Van Rijswick, R.; Van Rhee, C.

2013-01-01

Piston diaphragm pumps are used world-wide for the transport of aggressive and/or abrasive fluids in the chemical, mining and mineral processing industries. Figure 1 shows a cross section of a piston diaphragm pump as is used in the mining and mineral processing industries for the transport of

Quantification of the variability of diaphragm motion and implications for treatment margin construction

NARCIS (Netherlands)

Rit, Simon; van Herk, Marcel; Zijp, Lambert; Sonke, Jan-Jakob

2012-01-01

To quantify the variability of diaphragm motion during free-breathing radiotherapy of lung patients and its effect on treatment margins to account for geometric uncertainties. Thirty-three lung cancer patients were analyzed. Each patient had 5-19 cone-beam scans acquired during different treatment

Traumatic rupture of the diaphragm | Jamabo | Sahel Medical Journal

African Journals Online (AJOL)

Those treated for traumatic rupture of the diaphragm were selected and analyzed for age, gender, cause of injury, associated injuries sustained and mode of treatment. They were all treated at the University of Port Harcourt Teaching Hospital and a private clinic in Port Harcourt. Results: 12 patients had traumatic rupture of ...

Radial Field Piezoelectric Diaphragms

Science.gov (United States)

Bryant, R. G.; Effinger, R. T., IV; Copeland, B. M., Jr.

2002-01-01

A series of active piezoelectric diaphragms were fabricated and patterned with several geometrically defined Inter-Circulating Electrodes "ICE" and Interdigitated Ring Electrodes "ICE". When a voltage potential is applied to the electrodes, the result is a radially distributed electric field that mechanically strains the piezoceramic along the Z-axis (perpendicular to the applied electric field). Unlike other piezoelectric bender actuators, these Radial Field Diaphragms (RFDs) strain concentrically yet afford high displacements (several times that of the equivalent Unimorph) while maintaining a constant circumference. One of the more intriguing aspects is that the radial strain field reverses itself along the radius of the RFD while the tangential strain remains relatively constant. The result is a Z-deflection that has a conical profile. This paper covers the fabrication and characterization of the 5 cm. (2 in.) diaphragms as a function of poling field strength, ceramic thickness, electrode type and line spacing, as well as the surface topography, the resulting strain field and displacement as a function of applied voltage at low frequencies. The unique features of these RFDs include the ability to be clamped about their perimeter with little or no change in displacement, the environmentally insulated packaging, and a highly repeatable fabrication process that uses commodity materials.

The earliest history of diaphragm physiology.

Science.gov (United States)

Derenne, J P; Debru, A; Grassino, A E; Whitelaw, W A

1994-12-01

The diaphragm was recognized as a distinct anatomical structure in the earliest Greek writings. However, the precise description of wounds suffered by warriors during the Trojan war by Homer was not tied to any particular function. The diaphragm was assimilated to the region that harbours thought. The first physiologic explanations of respiration by Empedocles in the 5th century BC and the concepts introduced by Plato and Hippocrates did not include a significant participation of the diaphragm. Aristole was the first to link respiration to a particular organ and a specific movement of the thorax. However, he considered that it was the heart which caused the lungs to expand by heating them, and the lungs in turn forced the thorax to dilate, a concept which was to survive until the 17th century. As in Aristole's theory the diaphragm played no role in respiration and was just a fence separating the thorax from the abdomen. A major break through occurred in Alexandria in the 4th and 3rd century BC: Herophilus was the first to recognize that muscles were the agents of movement and Erasistratus performed animal experiments which showed that the respiratory muscles were the agents of respiratory movements, thus opening the way to the later discoveries of Galen.

Tumor motion prediction with the diaphragm as a surrogate: a feasibility study

International Nuclear Information System (INIS)

Cervino, Laura I; Jiang Yan; Sandhu, Ajay; Jiang, Steve B

2010-01-01

We have previously assessed the use of the diaphragm as a surrogate for predicting real-time tumor position with linear models built with training data extracted from the same treatment fraction (Cervino et al 2009 Phys. Med. Biol. 54 3529-41). However, practical use in the clinical setting requires the capability of predicting tumor position throughout the treatment course using a model built at the beginning of the course. We evaluate the inter-fraction applicability of linear models to predict superior-inferior tumor position based on diaphragm position using 21 fluoroscopic sequences from five lung cancer patients. Tumor position is predicted with models built during the first fluoroscopic sequence of each patient. Other fluoroscopic sets are registered to the first set with five different methods. The mean localization prediction error and maximum error at a 95% confidence level averaged over all patients are found to be 1.2 mm and 2.9 mm, respectively, for bony registration and 1.2 mm and 2.8 mm, respectively, for registration based on the mean position of the tumor in the first two breathing cycles. Other registration methods produce larger prediction errors. In the clinical setting, this prediction error could be added as a margin to the target volume. We therefore conclude that it is feasible to predict lung tumor motion with diaphragm with sufficient accuracy in the clinical setting. (note)

Mechanics of the canine diaphragm in pleural effusion.

Science.gov (United States)

De Troyer, André; Leduc, Dimitri; Cappello, Matteo; Gevenois, Pierre Alain

2012-09-01

Pleural effusion is a complicating feature of many diseases of the lung and pleura, but its effects on the mechanics of the diaphragm have not been assessed. In the present study, radiopaque markers were attached along muscle bundles in the midcostal region of the diaphragm in anesthetized dogs, and the three-dimensional location of the markers during relaxation before and after the stepwise introduction of liquid into the left or right pleural space and during phrenic nerve stimulation in the same conditions was determined using computed tomography. From these data, accurate measurements of diaphragm muscle length and displacement were obtained, and the changes in pleural and abdominal pressure were analyzed as functions of these parameters. The effect of liquid instillation on the axial position of rib 5 was also measured. The data showed that 1) liquid leaked through the dorsal mediastinal sheet behind the pericardium so that effusion was bilateral; 2) effusion caused a caudal displacement of the relaxed diaphragm; 3) this displacement was, compared with passive lung inflation, much larger than the cranial displacement of the ribs; and 4) the capacity of the diaphragm to generate pressure, in particular pleural pressure, decreased markedly as effusion increased, and this decrease was well explained by the decrease in active muscle length. It is concluded that pleural effusion has a major adverse effect on the pressure-generating capacity of the diaphragm and that this is the result of the action of hydrostatic forces on the muscle.

Parametric study of roof diaphragm stiffness requirements

International Nuclear Information System (INIS)

Jones, W.D.; Tenbus, M.A.

1991-01-01

A common assumption made in performing a dynamic seismic analysis for a building is that the roof/floor system is open-quotes rigidclose quotes. This assumption would appear to be reasonable for many of the structures found in nuclear power plants, since many of these structures are constructed of heavily reinforced concrete having floor/roof slabs at least two feet in thickness, and meet the code requirements for structural detailing for seismic design. The roofs of many Department of Energy (DOE) buildings at the Oak Ridge Y-12 Plant in Oak Ridge, Tennessee, have roofs constructed of either metal, precast concrete or gypsum plank deck overlaid with rigid insulation, tar and gravel. In performing natural phenomena hazard assessments for one such facility, it was assumed that the existing roof performed first as a flexible diaphragm (zero stiffness) and then, rigid (infinitely stiff). For the flexible diaphragm model it was determined that the building began to experience significant damage around 0.09 g's. For the rigid diaphragm model it was determined that no significant damage was observed below 0.20 g's. A Conceptual Design Report has been prepared for upgrading/replacing the roof of this building. The question that needed to be answered here was, open-quotes How stiff should the new roof diaphragm be in order to satisfy the rigid diaphragm assumption and, yet, be cost effective?close quotes. This paper presents a parametric study of a very simple structural system to show that the design of roof diaphragms needs to consider both strength and stiffness (frequency) requirements. This paper shows how the stiffness of a roof system affects the seismically induced loads in the lateral, vertical load resisting elements of a building and provides guidance in determining how open-quotes rigidclose quotes a roof system should be in order to accomplish a cost effective design

Comparison of Bigbag and Rayner620H intraocular lens in cataract surgeries in high myopia patients

Directory of Open Access Journals (Sweden)

Zhan-Jiang Liu

2016-01-01

Full Text Available AIM:To investigate the effects of Bigbag and Rayner620H intraocular lens in cataract surgeries in high myopia patients. METHODS:Seventy-seven patients(128 eyeswere treated by phacoemulsification combined with intraocular lens implantation from January 2014 to March 2015 in our hospital. Thirty-nine patients(65 eyeswere treated with Bigbag intraocular lens, 38 cases(63 eyeswere treated with Rayner620H. The best corrected visual acuity(BCVAdistribution, the actual refractive value, the difference between predictive refractive value and actual refractive value and complications were measured and recorded in the two groups at 1mo after surgeries. RESULTS:The difference between the two groups on BCVA are statistically significant(PWilcoxon rank sum test. The differences between predictive refractive value and actual refractive value of the two groups were statistically significant(PPCONCLUSION:The effect of Bigbag intraocular lens for patients with phacoemulsification and intraocular lens implantation is good, and it can reduce the risk of complications.

Validation of ultrasonography for non-invasive assessment of diaphragm function in muscular dystrophy.

Science.gov (United States)

Whitehead, Nicholas P; Bible, Kenneth L; Kim, Min Jeong; Odom, Guy L; Adams, Marvin E; Froehner, Stanley C

2016-12-15

Duchenne muscular dystrophy (DMD) is a severe, degenerative muscle disease that is commonly studied using the mdx mouse. The mdx diaphragm muscle closely mimics the pathophysiological changes in DMD muscles. mdx diaphragm force is commonly assessed ex vivo, precluding time course studies. Here we used ultrasonography to evaluate time-dependent changes in diaphragm function in vivo, by measuring diaphragm movement amplitude. In mdx mice, diaphragm amplitude decreased with age and values were much lower than for wild-type mice. Importantly, diaphragm amplitude strongly correlated with ex vivo specific force values. Micro-dystrophin administration increased mdx diaphragm amplitude by 26% after 4 weeks. Diaphragm amplitude correlated positively with ex vivo force values and negatively with diaphragm fibrosis, a major cause of DMD muscle weakness. These studies validate diaphragm ultrasonography as a reliable technique for assessing time-dependent changes in mdx diaphragm function in vivo. This technique will be valuable for testing potential therapies for DMD. Duchenne muscular dystrophy (DMD) is a severe, degenerative muscle disease caused by dystrophin mutations. The mdx mouse is a widely used animal model of DMD. The mdx diaphragm muscle most closely recapitulates key features of DMD muscles, including progressive fibrosis and considerable force loss. Diaphragm function in mdx mice is commonly evaluated by specific force measurements ex vivo. While useful, this method only measures force from a small muscle sample at one time point. Therefore, accurate assessment of diaphragm function in vivo would provide an important advance to study the time course of functional decline and treatment benefits. Here, we evaluated an ultrasonography technique for measuring time-dependent changes of diaphragm function in mdx mice. Diaphragm movement amplitude values for mdx mice were considerably lower than those for wild-type, decreased from 8 to 18 months of age, and correlated

Hyperglycemia-induced diaphragm weakness is mediated by oxidative stress

Science.gov (United States)

2014-01-01

Introduction A major consequence of ICU-acquired weakness (ICUAW) is diaphragm weakness, which prolongs the duration of mechanical ventilation. Hyperglycemia (HG) is a risk factor for ICUAW. However, the mechanisms underlying HG-induced respiratory muscle weakness are not known. Excessive reactive oxygen species (ROS) injure multiple tissues during HG, but only one study suggests that excessive ROS generation may be linked to HG-induced diaphragm weakness. We hypothesized that HG-induced diaphragm dysfunction is mediated by excessive superoxide generation and that administration of a specific superoxide scavenger, polyethylene glycol superoxide dismutase (PEG-SOD), would ameliorate these effects. Methods HG was induced in rats using streptozotocin (60 mg/kg intravenously) and the following groups assessed at two weeks: controls, HG, HG + PEG-SOD (2,000U/kg/d intraperitoneally for seven days), and HG + denatured (dn)PEG-SOD (2000U/kg/d intraperitoneally for seven days). PEG-SOD and dnPEG-SOD were administered on day 8, we measured diaphragm specific force generation in muscle strips, force-pCa relationships in single permeabilized fibers, contractile protein content and indices of oxidative stress. Results HG reduced diaphragm specific force generation, altered single fiber force-pCa relationships, depleted troponin T, and increased oxidative stress. PEG-SOD prevented HG-induced reductions in diaphragm specific force generation (for example 80 Hz force was 26.4 ± 0.9, 15.4 ± 0.9, 24.0 ± 1.5 and 14.9 ± 0.9 N/cm2 for control, HG, HG + PEG-SOD, and HG + dnPEG-SOD groups, respectively, P hyperglycemia-induced diaphragm dysfunction. This new mechanistic information could explain how HG alters diaphragm function during critical illness. PMID:24886999

Bending-induced electromechanical coupling and large piezoelectric response in a micromachined diaphragm

KAUST Repository

Wang, Zhihong

2013-11-04

We investigated the dependence of electromechanical coupling and the piezoelectric response of a micromachined Pb(Zr 0.52 Ti 0.48)O 3 (PZT) diaphragm on its curvature by observing the impedance spectrum and central deflection responses to a small AC voltage. The curvature of the diaphragm was controlled by applying air pressure to its back. We found that a depolarized flat diaphragm does not initially exhibit electromechanical coupling or the piezoelectric response. However, upon the application of static air pressure to the diaphragm, both electromechanical coupling and the piezoelectric response can be induced in the originally depolarized diaphragm. The piezoelectric response increases as the curvature increases and a giant piezoelectric response can be obtained from a bent diaphragm. The obtained results clearly demonstrate that a high strain gradient in a diaphragm can polarize a PZT film through a flexoelectric effect, and that the induced piezoelectric response of the diaphragm can be controlled by adjusting its curvature.

Evaluation of COPD's diaphragm motion extracted from 4D-MRI

Science.gov (United States)

Swastika, Windra; Masuda, Yoshitada; Kawata, Naoko; Matsumoto, Koji; Suzuki, Toshio; Iesato, Ken; Tada, Yuji; Sugiura, Toshihiko; Tanabe, Nobuhiro; Tatsumi, Koichiro; Ohnishi, Takashi; Haneishi, Hideaki

2015-03-01

We have developed a method called intersection profile method to construct a 4D-MRI (3D+time) from time-series of 2D-MRI. The basic idea is to find the best matching of the intersection profile from the time series of 2D-MRI in sagittal plane (navigator slice) and time series of 2D-MRI in coronal plane (data slice). In this study, we use 4D-MRI to semiautomatically extract the right diaphragm motion of 16 subjects (8 healthy subjects and 8 COPD patients). The diaphragm motion is then evaluated quantitatively by calculating the displacement of each subjects and normalized it. We also generate phase-length map to view and locate paradoxical motion of the COPD patients. The quantitative results of the normalized displacement shows that COPD patients tend to have smaller displacement compared to healthy subjects. The average normalized displacement of total 8 COPD patients is 9.4mm and the average of normalized displacement of 8 healthy volunteers is 15.3mm. The generated phase-length maps show that not all of the COPD patients have paradoxical motion, however if it has paradoxical motion, the phase-length map is able to locate where does it occur.

Long-term follow-up after scleral lens fixation in patients with Marfan syndrome.

Science.gov (United States)

Luebke, Jan; Reinhard, Thomas; Agostini, Hansjuergen; Boehringer, Daniel; Eberwein, Philipp

2017-12-06

The dislocation of the crystalline lens is a common finding in patients with Marfan syndrome (MFS). Scleral intraocular lens (IOL) fixation is an accepted treatment method of this complication. To now, no long-term data on scleral IOL fixation in MFS exist. We present a retrospective study of 27 eyes of 17 MFS patients that underwent scleral lens fixation at our clinic between 1999 and 2012. These patients are compared to an age- and surgeon-matched group of 31 eyes of 27 patients who underwent the same procedure for reasons other than MFS. The median age in the MFS group was 35.4 years versus 35.6 years in the non-MFS group. The median follow-up was 4 years for MFS and 3 years for non-MFS. In the MFS group, significantly more IOL-dislocations occurred than compared to the non-MFS group (30% vs. 6.5%, p = 0.02). Retinal detachment occurred in four MFS-eyes compared to three eyes in the non-MFS group. Biometry prediction error was 1.11 diopters (D) for MFS and 1.33 D for non-MFS (p = 0.11). Median BCVA (best-corrected visual acuity, logMAR) was 0.1 in the MFS group versus 0.3 in non-MFS patients. Scleral lens fixation in MFS patients achieves satisfying visual and refractive outcomes. Our data shows a significantly higher rate of IOL dislocations in patients with MFS. We therefore recommend addressing this complication preoperatively.

Inhalation of Budesonide/Formoterol Increases Diaphragm Muscle Contractility

Directory of Open Access Journals (Sweden)

Chiyohiko Shindoh

2012-01-01

Conclusions: BUD/FORM inhalation has an inotropic effect on diaphragm muscle, protects diaphragm muscle deterioration after endotoxin injection, and inhibits NO production. Increments in muscle contractility with BUD/FORM inhalation are induced through a synergistic effect of an anti-inflammatory agent and 02-agonist.

Detecting defects in diaphragm walls prior to excavation

NARCIS (Netherlands)

Spruit, R.; Hopman, V.; Van Tol, A.F.; Broere, W.

2011-01-01

Recent incidents with leaking diaphragm walls during construction of subway lines in Amsterdam and Rotterdam (Netherlands) have led to reconsideration of the diaphragm wall as a retaining wall construction for deep excavations. In our opinion the joints between the panels are the weak spot. During

Evaluation of phrenic nerve and diaphragm function with peripheral nerve stimulation and M-mode ultrasonography in potential pediatric phrenic nerve or diaphragm pacing candidates.

Science.gov (United States)

Skalsky, Andrew J; Lesser, Daniel J; McDonald, Craig M

2015-02-01

Assessing phrenic nerve function in the setting of diaphragmatic paralysis in diaphragm pacing candidates can be challenging. Traditional imaging modalities and electrodiagnostic evaluations are technically difficult. Either modality alone is not a direct measure of the function of the phrenic nerve and diaphragm unit. In this article, the authors present their method for evaluating phrenic nerve function and the resulting diaphragm function. Stimulating the phrenic nerve with transcutaneous stimulation and directly observing the resulting movement of the hemidiaphragm with M-mode ultrasonography provides quantitative data for predicting the success of advancing technologies such as phrenic nerve pacing and diaphragm pacing. Copyright © 2015 Elsevier Inc. All rights reserved.

GND-PCA-based statistical modeling of diaphragm motion extracted from 4D MRI.

Science.gov (United States)

Swastika, Windra; Masuda, Yoshitada; Xu, Rui; Kido, Shoji; Chen, Yen-Wei; Haneishi, Hideaki

2013-01-01

We analyzed a statistical model of diaphragm motion using regular principal component analysis (PCA) and generalized N-dimensional PCA (GND-PCA). First, we generate 4D MRI of respiratory motion from 2D MRI using an intersection profile method. We then extract semiautomatically the diaphragm boundary from the 4D-MRI to get subject-specific diaphragm motion. In order to build a general statistical model of diaphragm motion, we normalize the diaphragm motion in time and spatial domains and evaluate the diaphragm motion model of 10 healthy subjects by applying regular PCA and GND-PCA. We also validate the results using the leave-one-out method. The results show that the first three principal components of regular PCA contain more than 98% of the total variation of diaphragm motion. However, validation using leave-one-out method gives up to 5.0 mm mean of error for right diaphragm motion and 3.8 mm mean of error for left diaphragm motion. Model analysis using GND-PCA provides about 1 mm margin of error and is able to reconstruct the diaphragm model by fewer samples.

Free Piston Double Diaphragm Shock Tube

OpenAIRE

OGURA, Eiji; FUNABIKI, Katsushi; SATO, Shunichi; ABE, Takashi; 小倉, 栄二; 船曳, 勝之; 佐藤, 俊逸; 安部, 隆士

1997-01-01

A free piston double diaphragm shock tube was newly developed for generation of high Mach number shock wave. Its characteristics was investigated for various operation parameters; such as a strength of the diaphragm at the end of the comparession tube, an initial pressure of low pressure tube, an initial pressure of medium pressure tube and the volume of compression tube. Under the restriction of fixed pressures for the driver high pressure tube (32×10^5Pa) and the low pressure tube (40Pa) in...

Diaphragm walling for Sizewell B sets records

International Nuclear Information System (INIS)

Anon.

1988-01-01

The first phase of construction of the Sizewell-B nuclear reactor has been completed. This was the building of a diaphragm wall around the site. It is one of the largest and deepest diaphragm walls to be installed in Europe. The site can be pumped dry of groundwater and the foundations constructed in the dry. The specifications of the wall and its construction, using two Hydrofraise excavation rigs, are described. The excavated material is brought up as a slurry and the (bentonite) slurry is cleaned and desanded. Most of the wall has been formed using a plastic concrete but reinforced concrete has been used for some stretches. The diaphragm wall, which is 1258m long and 55m deep on average, was built in 19 weeks. (U.K.)

Safety and efficacy of diaphragm pacing in patients with respiratory insufficiency due to amyotrophic lateral sclerosis (DiPALS): a multicentre, open-label, randomised controlled trial.

Science.gov (United States)

2015-09-01

Non-invasive ventilation is part of the standard of care for treatment of respiratory failure in patients with amyotrophic lateral sclerosis (ALS). The NeuRx RA/4 Diaphragm Pacing System has received Humanitarian Device Exemption approval from the US Food and Drug Administration for treatment of respiratory failure in patients with ALS. We aimed to establish the safety and efficacy of diaphragm pacing with this system in patients with respiratory muscle weakness due to ALS. We undertook a multicentre, open-label, randomised controlled trial at seven specialist ALS and respiratory centres in the UK. Eligible participants were aged 18 years or older with laboratory supported probable, clinically probable, or clinically definite ALS; stable riluzole treatment for at least 30 days; and respiratory insufficiency. We randomly assigned participants (1:1), via a centralised web-based randomisation system with minimisation that balanced patients for age, sex, forced vital capacity, and bulbar function, to receive either non-invasive ventilation plus pacing with the NeuRx RA/4 Diaphragm Pacing System or non-invasive ventilation alone. Patients, carers, and outcome assessors were not masked to treatment allocation. The primary outcome was overall survival, defined as the time from randomisation to death from any cause. Analysis was by intention to treat. This trial is registered, ISRCTN number 53817913. Between Dec 5, 2011, and Dec 18, 2013, we randomly assigned 74 participants to receive either non-invasive ventilation alone (n=37) or non-invasive ventilation plus diaphragm pacing (n=37). On Dec 18, 2013, the Data Monitoring and Ethics Committee (DMEC) recommended suspension of recruitment on the basis of overall survival figures. Randomly assigned participants continued as per the study protocol until June 23, 2014, when the DMEC advised discontinuation of pacing in all patients. Follow-up assessments continued until the planned end of the study in December, 2014. Survival

Global Proteome Changes in the Rat Diaphragm Induced by Endurance Exercise Training.

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Kurt J Sollanek

Full Text Available Mechanical ventilation (MV is a life-saving intervention for many critically ill patients. Unfortunately, prolonged MV results in the rapid development of diaphragmatic atrophy and weakness. Importantly, endurance exercise training results in a diaphragmatic phenotype that is protected against ventilator-induced diaphragmatic atrophy and weakness. The mechanisms responsible for this exercise-induced protection against ventilator-induced diaphragmatic atrophy remain unknown. Therefore, to investigate exercise-induced changes in diaphragm muscle proteins, we compared the diaphragmatic proteome from sedentary and exercise-trained rats. Specifically, using label-free liquid chromatography-mass spectrometry, we performed a proteomics analysis of both soluble proteins and mitochondrial proteins isolated from diaphragm muscle. The total number of diaphragm proteins profiled in the soluble protein fraction and mitochondrial protein fraction were 813 and 732, respectively. Endurance exercise training significantly (P<0.05, FDR <10% altered the abundance of 70 proteins in the soluble diaphragm proteome and 25 proteins of the mitochondrial proteome. In particular, key cytoprotective proteins that increased in relative abundance following exercise training included mitochondrial fission process 1 (Mtfp1; MTP18, 3-mercaptopyruvate sulfurtransferase (3MPST, microsomal glutathione S-transferase 3 (Mgst3; GST-III, and heat shock protein 70 kDa protein 1A/1B (HSP70. While these proteins are known to be cytoprotective in several cell types, the cyto-protective roles of these proteins have yet to be fully elucidated in diaphragm muscle fibers. Based upon these important findings, future experiments can now determine which of these diaphragmatic proteins are sufficient and/or required to promote exercise-induced protection against inactivity-induced muscle atrophy.

Functional restoration of the paralyzed diaphragm in high cervical quadriplegia via phrenic nerve neurotization utilizing the functional spinal accessory nerve.

Science.gov (United States)

Yang, Ming-liang; Li, Jian-jun; Zhang, Shao-cheng; Du, Liang-jie; Gao, Feng; Li, Jun; Wang, Yu-ming; Gong, Hui-ming; Cheng, Liang

2011-08-01

The authors report a case of functional improvement of the paralyzed diaphragm in high cervical quadriplegia via phrenic nerve neurotization using a functional spinal accessory nerve. Complete spinal cord injury at the C-2 level was diagnosed in a 44-year-old man. Left diaphragm activity was decreased, and the right diaphragm was completely paralyzed. When the level of metabolism or activity (for example, fever, sitting, or speech) slightly increased, dyspnea occurred. The patient underwent neurotization of the right phrenic nerve with the trapezius branch of the right spinal accessory nerve at 11 months postinjury. Four weeks after surgery, training of the synchronous activities of the trapezius muscle and inspiration was conducted. Six months after surgery, motion was observed in the previously paralyzed right diaphragm. The lung function evaluation indicated improvements in vital capacity and tidal volume. This patient was able to sit in a wheelchair and conduct outdoor activities without assisted ventilation 12 months after surgery.

Giant flexoelectric polarization in a micromachined ferroelectric diaphragm

KAUST Repository

Wang, Zhihong

2012-08-14

The coupling between dielectric polarization and strain gradient, known as flexoelectricity, becomes significantly large on the micro- and nanoscale. Here, it is shown that giant flexoelectric polarization can reverse remnant ferroelectric polarization in a bent Pb(Zr0.52Ti0.48) O3 (PZT) diaphragm fabricated by micromachining. The polarization induced by the strain gradient and the switching behaviors of the polarization in response to an external electric field are investigated by observing the electromechanical coupling of the diaphragm. The method allows determination of the absolute zero polarization state in a PZT film, which is impossible using other existing methods. Based on the observation of the absolute zero polarization state and the assumption that bending of the diaphragm is the only source of the self-polarization, the upper bound of flexoelectric coefficient of PZT film is calculated to be as large as 2.0 × 10-4 C m -1. The strain gradient induced by bending the diaphragm is measured to be on the order of 102 m-1, three orders of magnitude larger than that obtained in the bulk material. Because of this large strain gradient, the estimated giant flexoelectric polarization in the bent diaphragm is on the same order of magnitude as the normal remnant ferroelectric polarization of PZT film. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Influence of double-diaphragm vacuum compaction on deformation during forming of composite prepregs

Directory of Open Access Journals (Sweden)

Hassan Alshahrani

2016-12-01

Full Text Available During the diaphragm forming process, a vacuum seal is applied between the upper and lower diaphragms to compact and hold the laminate. Therefore, a thorough characterization of the in-plane shear behavior of fabrics under diaphragm forming conditions must take into account the effect of vacuum-sealing and compaction between the two diaphragms during bias extension. The study presented here examined the shear angles of out-of-autoclave 8-harness satin woven carbon/epoxy prepregs under diaphragm compaction. A bias extension test was conducted to study the effect of diaphragm compaction and ply interactions on shear properties. The test was performed at different compaction levels, and changes in shear angle with respect to vacuum levels and diaphragm compaction forces were observed. The contribution of diaphragm material and ply interaction to shear stiffness was evaluated and compared with results from a direct bias extension test. The samples were tested at both room temperature and at elevated temperatures using a radiant heater. The results show that shear angle decreases significantly as vacuum pressure and compaction is applied between the two diaphragms. This finding indicates that vacuum levels and compaction forces have a significant influence on the deformation limit and wrinkling onset during the diaphragm forming process.

Bilateral spontaneous dislocation of posterior chamber intraocular lens in a patient with gyrate atrophy

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Michael Kinori

2012-01-01

Full Text Available We report a patient with gyrate atrophy, a rare metabolic disease, who had bilateral late spontaneous posterior dislocation of in-the-bag posterior chamber intraocular lens (PCIOL. He underwent pars plana vitrectomy, PCIOL retrieval and anterior chamber intraocular lens implantation in both eyes. This report may imply that patients with gyrate atrophy are at risk for spontaneous dislocation of intraocular lenses.

Functional assessment of the diaphragm by speckle tracking ultrasound during inspiratory loading

NARCIS (Netherlands)

Mos-Oppersma, Eline; Hatam, Nima; Doorduin, Jonne; van der Hoeven, Johannes G.; Marx, Gernot; Goetzenich, Andreas; Fritsch, Sebastian; Heunks, Leo M.A.; Bruells, Christian S.

2017-01-01

Assessment of diaphragmatic effort is challenging, especially in critically ill patients in the phase of weaning. Fractional thickening during inspiration assessed by ultrasound has been used to estimate diaphragm effort. It is unknown whether more sophisticated ultrasound techniques such as speckle

Efficacy evaluation of laparoscopy assisted ultrasound guided radiofrequency ablation in the treatment of hepatocellular carcinoma beneath the diaphragm

Directory of Open Access Journals (Sweden)

Song WANG

2017-06-01

Full Text Available Objective To explore the feasibility, safety and efficacy of laparoscopy assisted ultrasound guided radiofrequency ablation (RFA in the treatment of hepatocellular carcinoma (HCC beneath the diaphragm. Methods Twenty- three consecutive patients with solitary HCC beneath the diaphragm were treated by laparoscopy assisted ultrasound guided RFA in the Chinese PLA General Hospital from January 2013 to March 2016. We observed the perioperative complications and followed- up long-term effect. Results All the 23 patients successfully underwent laparoscopy assisted ultrasound guided radiofrequency ablation. No serious complications such as massive hemorrhage, biliary fistula and severe pleural effusion, hemopneumothorax occurred in the patients during perioperative period. CT examination 2-3 days after the operation revealed that the tumor was completely covered by the ablation area. Besides, the survival condition was satisfactory during follow-up period of 9-38 months. Conclusion Laparoscopy-assisted ultrasound-guided radiofrequency ablation is effective and safe for HCC beneath the diaphragm. DOI: 10.11855/j.issn.0577-7402.2017.05.16

Mathematical Modeling of Diaphragm Pneumatic Motors

Directory of Open Access Journals (Sweden)

Fojtášek Kamil

2014-03-01

Full Text Available Pneumatic diaphragm motors belong to the group of motors with elastic working parts. This part is usually made of rubber with a textile insert and it is deformed under the pressure of a compressed air or from the external mass load. This is resulting in a final working effect. In this type of motors are in contact two different elastic environments – the compressed air and the esaltic part. These motors are mainly the low-stroke and working with relatively large forces. This paper presents mathematical modeling static properties of diaphragm motors.

Partial Support Ventilation and Mitochondrial-Targeted Antioxidants Protect against Ventilator-Induced Decreases in Diaphragm Muscle Protein Synthesis.

Science.gov (United States)

Hudson, Matthew B; Smuder, Ashley J; Nelson, W Bradley; Wiggs, Michael P; Shimkus, Kevin L; Fluckey, James D; Szeto, Hazel H; Powers, Scott K

2015-01-01

Mechanical ventilation (MV) is a life-saving intervention in patients in respiratory failure. Unfortunately, prolonged MV results in the rapid development of diaphragm atrophy and weakness. MV-induced diaphragmatic weakness is significant because inspiratory muscle dysfunction is a risk factor for problematic weaning from MV. Therefore, developing a clinical intervention to prevent MV-induced diaphragm atrophy is important. In this regard, MV-induced diaphragmatic atrophy occurs due to both increased proteolysis and decreased protein synthesis. While efforts to impede MV-induced increased proteolysis in the diaphragm are well-documented, only one study has investigated methods of preserving diaphragmatic protein synthesis during prolonged MV. Therefore, we evaluated the efficacy of two therapeutic interventions that, conceptually, have the potential to sustain protein synthesis in the rat diaphragm during prolonged MV. Specifically, these experiments were designed to: 1) determine if partial-support MV will protect against the decrease in diaphragmatic protein synthesis that occurs during prolonged full-support MV; and 2) establish if treatment with a mitochondrial-targeted antioxidant will maintain diaphragm protein synthesis during full-support MV. Compared to spontaneously breathing animals, full support MV resulted in a significant decline in diaphragmatic protein synthesis during 12 hours of MV. In contrast, diaphragm protein synthesis rates were maintained during partial support MV at levels comparable to spontaneous breathing animals. Further, treatment of animals with a mitochondrial-targeted antioxidant prevented oxidative stress during full support MV and maintained diaphragm protein synthesis at the level of spontaneous breathing animals. We conclude that treatment with mitochondrial-targeted antioxidants or the use of partial-support MV are potential strategies to preserve diaphragm protein synthesis during prolonged MV.

Partial Support Ventilation and Mitochondrial-Targeted Antioxidants Protect against Ventilator-Induced Decreases in Diaphragm Muscle Protein Synthesis.

Directory of Open Access Journals (Sweden)

Matthew B Hudson

Full Text Available Mechanical ventilation (MV is a life-saving intervention in patients in respiratory failure. Unfortunately, prolonged MV results in the rapid development of diaphragm atrophy and weakness. MV-induced diaphragmatic weakness is significant because inspiratory muscle dysfunction is a risk factor for problematic weaning from MV. Therefore, developing a clinical intervention to prevent MV-induced diaphragm atrophy is important. In this regard, MV-induced diaphragmatic atrophy occurs due to both increased proteolysis and decreased protein synthesis. While efforts to impede MV-induced increased proteolysis in the diaphragm are well-documented, only one study has investigated methods of preserving diaphragmatic protein synthesis during prolonged MV. Therefore, we evaluated the efficacy of two therapeutic interventions that, conceptually, have the potential to sustain protein synthesis in the rat diaphragm during prolonged MV. Specifically, these experiments were designed to: 1 determine if partial-support MV will protect against the decrease in diaphragmatic protein synthesis that occurs during prolonged full-support MV; and 2 establish if treatment with a mitochondrial-targeted antioxidant will maintain diaphragm protein synthesis during full-support MV. Compared to spontaneously breathing animals, full support MV resulted in a significant decline in diaphragmatic protein synthesis during 12 hours of MV. In contrast, diaphragm protein synthesis rates were maintained during partial support MV at levels comparable to spontaneous breathing animals. Further, treatment of animals with a mitochondrial-targeted antioxidant prevented oxidative stress during full support MV and maintained diaphragm protein synthesis at the level of spontaneous breathing animals. We conclude that treatment with mitochondrial-targeted antioxidants or the use of partial-support MV are potential strategies to preserve diaphragm protein synthesis during prolonged MV.

Autophagy-associated atrophy and metabolic remodeling of the mouse diaphragm after short-term intermittent hypoxia.

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Christian Giordano

Full Text Available Short-term intermittent hypoxia (IH is common in patients with acute respiratory disorders. Although prolonged exposure to hypoxia induces atrophy and increased fatigability of skeletal muscle, the response to short-term IH is less well known. We hypothesized that the diaphragm and limb muscles would adapt differently to short-term IH given that hypoxia stimulates ventilation and triggers a superimposed exercise stimulus in the diaphragm.We determined the structural, metabolic, and contractile properties of the mouse diaphragm after 4 days of IH (8 hours per day, 30 episodes per hour to a FiO2 nadir=6%, and compared responses in the diaphragm to a commonly studied reference limb muscle, the tibialis anterior. Outcome measures included muscle fiber size, assays of muscle proteolysis (calpain, ubiquitin-proteasome, and autophagy pathways, markers of oxidative stress and mitochondrial function, quantification of intramyocellular lipid and lipid metabolism genes, type I myosin heavy chain (MyHC expression, and in vitro contractile properties.After 4 days of IH, the diaphragm alone demonstrated significant atrophy (30% decrease of myofiber size together with increased LC3B-II protein (2.4-fold and mRNA markers of the autophagy pathway (LC3B, Gabarapl1, Bnip3, whereas active calpain and E3 ubiquitin ligases (MuRF1, atrogin-1 were unaffected in both muscles. Succinate dehydrogenase activity was significantly reduced by IH in both muscles. However, only the diaphragm exhibited increased intramyocellular lipid droplets (2.5-fold after IH, along with upregulation of genes linked to activated lipid metabolism. In addition, although the diaphragm showed evidence for acute fatigue immediately following IH, it underwent an adaptive fiber type switch toward slow type I MyHC-expressing fibers, associated with greater intrinsic endurance of the muscle during repetitive stimulation in vitro.Short-term IH induces preferential atrophy in the mouse diaphragm

A Study of Free-Piston Double-Diaphragm Drivers for Expansion Tubes. Report 1

Science.gov (United States)

Kendall, M. A.

1997-01-01

In recent years the free-piston double-diaphragm driver has been used to increase the performance of the XI pilot expansion tube to super-orbital test conditions. However, the actual performance of the double-diaphragm driver was found to be considerably less than ideal. An experimental study of the double-diaphragm driver was carried out on the XI facility over a range of conditions with the objective of determining the effect of. heat losses; and the non-ideal rupture of the 'light' secondary diaphragm on the driver performance. The disparity between the theoretical and measured performance envelope are highlighted. A viscous limit for the experiments vas established. Heat transfer behind the primary shock is shown to be the mechanism behind this limit Incident, reflected and transmitted shock trajectories for the secondary diaphragm were experimentally determined and compared with computed trajectories from a one-dimensional diaphragm inertia model. It was found that the diaphragm did influence the unsteady expansion. A good agreement between experimental and computed shock trajectories was obtained using a diaphragm inertia model assuming that the diaphragm mass became negligible 3 microns after shock impact.

Hypoxia-induced dysfunction of rat diaphragm: role of peroxynitrite.

NARCIS (Netherlands)

Zhu, X.; Heunks, L.M.A.; Versteeg, E.M.M.; Heijden, E. van der; Ennen, L.; Kuppevelt, A.H.M.S.M. van; Vina, J.; Dekhuijzen, P.N.R.

2005-01-01

Oxidants may play a role in hypoxia-induced respiratory muscle dysfunction. In the present study we hypothesized that hypoxia-induced impairment in diaphragm contractility is associated with elevated peroxynitrite generation. In addition, we hypothesized that strenuous contractility of the diaphragm

Patient characteristics, diagnosis, and treatment of non-contact lens related Acanthamoeba keratitis.

Science.gov (United States)

Sharma, S; Garg, P; Rao, G N

2000-10-01

To review the clinical characteristics, diagnosis, and visual outcome in patients with non-contact lens related Acanthamoeba keratitis and compare the findings with reported series of contact lens associated Acanthamoeba keratitis. Medical and microbiology records of 39 consecutive patients with a diagnosis of Acanthamoeba keratitis, at a tertiary eyecare centre in India between January 1996 and June 1998, were analysed retrospectively. A majority of the patients presented with poor visual acuity and large corneal stromal infiltrates (mean size 38.20 (SD 26. 18) mm). A predisposing factor was elicited in 19/39 (48.7%) patients (trauma 15, dirty water splash three, leaf juice one). None of the patients had worn contact lenses. Most patients (26/39 (66. 6%)) came from a low socioeconomic background. Complaint of severe pain was not a significant feature and radial keratoneuritis was seen in 1/39 (2.5%) patients. A ring infiltrate was present in 41.1% of cases. A clinical diagnosis of fungal keratitis was made in 45% of the patients before they were seen by us. However, all patients were diagnosed microbiologically at our institute based on demonstration of Acanthamoeba cysts in corneal scrapings (34/39) and/or culture of Acanthamoeba (34/39). Treatment with biguanides (PHMB, 15/38 (39.4%), PHMB with CHx, 23/38 (60.5%), one patient did not return for treatment) resulted in healing with scar formation in 27 out of 31(87.0%) followed up patients (mean time to healing 106.9 days). Overall visual outcome was poor with no statistical difference between cases diagnosed within 30 days (early) or 30 days after (late) start of symptoms. The visual outcome in cases requiring tissue adhesive (five) and keratoplasty (three) was also poor. This is thought to be the largest series of cases of Acanthamoeba keratitis in non-contact lens wearers. In such cases, the disease is advanced at presentation in most patients, pathognomonic clinical features are often not seen, disease

Effect of flexure beam geometry and material on the displacement of piezo actuated diaphragm for micropump

Science.gov (United States)

Roopa, R.; Navin Karanth, P.; Kulkarni, S. M.

2018-02-01

In this paper, we present a COMSOL analysis of flexure diaphragm for piezo actuated valveless micropump. Diaphragms play an important role in micropumps, till now plane diaphragms are commonly used in micropumps. Use of compliant flexure hinges in diaphragm and other MEMS application is one of the new approach to achieving high deflection in diaphragm at low operating voltage. Flexures hinges in diaphragm acts as simply supported beam. Out-off plane compliance value and stiffness is considered for the selection of proper flexure for diaphragm. Diaphragm material also plays an important role in the diaphragm central deflection. Factor considered for diaphragm material selection is resilience; it is the ratio of yield stress to static modulus. Higher is the resilience will leads to higher deflection generated, it also imparts good compliance. Based on the resilience beryllium copper, stainless steel and brass materials are selected for diaphragm analysis. Simulations have been performed using COMSOL multiphysics. This study reports the effect of flexure hinge geometry and diaphragm material on the central deflection of diaphragms and compared with existing plane diaphragm. Simulation results illustrates that the deflection of three flexure diaphragm with 2mm width and 2mm length flexure is 6.75µm for stainless steel, 10.89 for beryllium copper and 12.10µm for brass, at 140V which is approximately twice that of plane diaphragm deflection. The maximum in both plane and three flexure diaphragm deflection is obtained for brass diaphragm compared to stainless steel and beryllium copper.

Feasibility of navigator setting on the left diaphragm for whole-heart coronary MRA. A study in healthy volunteers

International Nuclear Information System (INIS)

Watanabe, Kunihiro; Suzuki, Takayoshi; Maruyama, Kazuhiro; Noda, Mayumi; Fujita, Mitsuo; Morita, Satoru; Ohnishi, Takahiro

2009-01-01

We prospectively compared the quality of images obtained by navigator setting on the left and right diaphragm on whole-heart coronary magnetic resonance angiography (WHCMRA). In 10 healthy volunteers, we performed free-breathing, 3-dimensional segmented true fast imaging with steady-state precession (trueFISP) WHCMRA by setting the navigator on the left and right diaphragm in random order. For the left diaphragm, we set the navigator outside the scope of the heart to avoid the influence on coronary arteries. We compared image acquisition time and visible length of coronary arteries using paired t-test and subjective image quality on a 4-point scale (1, poor; 4, excellent) using Wilcoxon signed-rank test. Mean overall subjective image quality was significantly better in the left diaphragm than the right (3.3±0.7 versus 2.9±0.9, P=0.02). Mean overall visible length of the coronary arteries was significantly better in the left diaphragm than the right (115.4±31.1 vs. 112.6±29.9 mm, P=0.02). Mean acquisition time between the left and right diaphragm was not significantly different (15.6±5.0 versus 16.0±5.7 min, P=0.79). In this small group of healthy volunteers, navigator setting for WHCMRA was superior on the left diaphragm than the right; however, feasibility of the technique requires additional consideration in a larger group of actual patients. (author)

Treating traumatic injuries of the diaphragm

Directory of Open Access Journals (Sweden)

Dwivedi Sankalp

2010-01-01

Full Text Available Traumatic diaphragmatic injury (DI is a unique clinical entity that is usually occult and can easily be missed. Their delayed presentation can be due to the delayed rupture of the diaphragm or delayed detection of diaphragmatic rupture, making the accurate diagnosis of DI challenging to the trauma surgeons. An emergency laparotomy and thorough exploration followed by the repair of the defect is the gold standard for the management of these cases. We report a case of blunt DI in an elderly gentleman and present a comprehensive overview for the management of traumatic injuries of the diaphragm.

Experimental investigation of solar powered diaphragm and helical pumps

Science.gov (United States)

For several years, many types of solar powered water pumping systems were evaluated, and in this paper, diaphragm and helical solar photovoltaic (PV) powered water pumping systems are discussed. Data were collected on diaphragm and helical pumps which were powered by different solar PV arrays at mul...

Diaphragm electromyographic activity following unilateral midcervical contusion injury in rats

Science.gov (United States)

Sieck, Gary C.

2016-01-01

Contusion-type injuries to the spinal cord are characterized by tissue loss and disruption of spinal pathways. Midcervical spinal cord injuries impair the function of respiratory muscles and may contribute to significant respiratory complications. This study systematically assessed the impact of a 100-kDy unilateral C4 contusion injury on diaphragm muscle activity across a range of motor behaviors in rats. Chronic diaphragm electromyography (EMG) was recorded before injury and at 1 and 7 days postinjury (DPI). Histological analyses assessed the extent of perineuronal net formation, white-matter sparing, and phrenic motoneuron loss. At 7 DPI, ∼45% of phrenic motoneurons were lost ipsilaterally. Relative diaphragm root mean square (RMS) EMG activity increased bilaterally across a range of motor behaviors by 7 DPI. The increase in diaphragm RMS EMG activity was associated with an increase in neural drive (RMS value at 75 ms after the onset of diaphragm activity) and was more pronounced during higher force, nonventilatory motor behaviors. Animals in the contusion group displayed a transient decrease in respiratory rate and an increase in burst duration at 1 DPI. By 7 days, following midcervical contusion, there was significant perineuronal net formation and white-matter loss that spanned 1 mm around the injury epicenter. Taken together, these findings are consistent with increased recruitment of remaining motor units, including more fatigable, high-threshold motor units, during higher force, nonventilatory behaviors. Changes in diaphragm EMG activity following midcervical contusion injury reflect complex adaptations in neuromotor control that may increase the risk of motor-unit fatigue and compromise the ability to sustain higher force diaphragm efforts. NEW & NOTEWORTHY The present study shows that unilateral contusion injury at C4 results in substantial loss of phrenic motoneurons but increased diaphragm muscle activity across a range of ventilatory and higher

TU-E-201-03: Eye Lens Dosimetry in Radiotherapy Using Contact Lens-Shaped Applicator

Energy Technology Data Exchange (ETDEWEB)

Park, J. [Seoul National University Hospital (Korea, Republic of)

2015-06-15

Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bomb survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on

TU-E-201-03: Eye Lens Dosimetry in Radiotherapy Using Contact Lens-Shaped Applicator

International Nuclear Information System (INIS)

Park, J.

2015-01-01

Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bomb survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on

Effect of maternal steroid on developing diaphragm integrity.

Directory of Open Access Journals (Sweden)

Yong Song

Full Text Available Antenatal steroids reduce the severity of initial respiratory distress of premature newborn babies but may have an adverse impact on other body organs. The study aimed to examine the effect of maternal steroids on postnatal respiratory muscle function during development and elucidate the mechanisms underlying the potential myopathy in newborn rats. Pregnant rats were treated with intramuscular injections of 0.5 mg/kg betamethasone 7 d and 3 d before birth. Newborn diaphragms were dissected for assessment of contractile function at 2 d, 7 d or 21 d postnatal age (PNA, compared with age-matched controls. The expression of myosin heavy chain (MHC isoforms and atrophy-related genes and activity of intracellular molecular signalling were measured using quantitative PCR and/or Western blot. With advancing PNA, neonatal MHC gene expression decreased progressively while MHC IIb and IIx isoforms increased. Protein metabolic signalling showed high baseline activity at 2 d PNA, and significantly declined at 7 d and 21 d. Antenatal administration of betamethasone significantly decreased diaphragm force production, fatigue resistance, total fast fibre content and anabolic signalling activity (Akt and 4E-BP1 in 21 d diaphragm. These responses were not observed in 2 d or 7 d postnatal diaphragm. Results demonstrate that maternal betamethasone treatment causes postnatal diaphragmatic dysfunction at 21 d PNA, which is attributed to MHC II protein loss and impairment of the anabolic signalling pathway. Developmental modifications in MHC fibre composition and protein signalling account for the age-specific diaphragm dysfunction.

Microfluidic Pumps Containing Teflon [Trademark] AF Diaphragms

Science.gov (United States)

Willis, Peter; White, Victor; Grunthaner, Frank; Ikeda, Mike; Mathies, Richard A.

2009-01-01

Microfluidic pumps and valves based on pneumatically actuated diaphragms made of Teflon AF polymers are being developed for incorporation into laboratory-on-a-chip devices that must perform well over temperature ranges wider than those of prior diaphragm-based microfluidic pumps and valves. Other potential applications include implanted biomedical microfluidic devices, wherein the biocompatability of Teflon AF polymers would be highly advantageous. These pumps and valves have been demonstrated to function stably after cycling through temperatures from -125 to 120 C. These pumps and valves are intended to be successors to similar prior pumps and valves containing diaphragms made of polydimethylsiloxane (PDMS) [commonly known as silicone rubber]. The PDMS-containing valves ae designed to function stably only within the temperature range from 5 to 80 C. Undesirably, PDMS membranes are somwehat porous and retain water. PDMS is especially unsuitable for use at temperatures below 0 C because the formation of ice crystals increases porosity and introduces microshear.

Audiovisual biofeedback improves diaphragm motion reproducibility in MRI

Science.gov (United States)

Kim, Taeho; Pollock, Sean; Lee, Danny; O’Brien, Ricky; Keall, Paul

2012-01-01

Purpose: In lung radiotherapy, variations in cycle-to-cycle breathing results in four-dimensional computed tomography imaging artifacts, leading to inaccurate beam coverage and tumor targeting. In previous studies, the effect of audiovisual (AV) biofeedback on the external respiratory signal reproducibility has been investigated but the internal anatomy motion has not been fully studied. The aim of this study is to test the hypothesis that AV biofeedback improves diaphragm motion reproducibility of internal anatomy using magnetic resonance imaging (MRI). Methods: To test the hypothesis 15 healthy human subjects were enrolled in an ethics-approved AV biofeedback study consisting of two imaging sessions spaced ∼1 week apart. Within each session MR images were acquired under free breathing and AV biofeedback conditions. The respiratory signal to the AV biofeedback system utilized optical monitoring of an external marker placed on the abdomen. Synchronously, serial thoracic 2D MR images were obtained to measure the diaphragm motion using a fast gradient-recalled-echo MR pulse sequence in both coronal and sagittal planes. The improvement in the diaphragm motion reproducibility using the AV biofeedback system was quantified by comparing cycle-to-cycle variability in displacement, respiratory period, and baseline drift. Additionally, the variation in improvement between the two sessions was also quantified. Results: The average root mean square error (RMSE) of diaphragm cycle-to-cycle displacement was reduced from 2.6 mm with free breathing to 1.6 mm (38% reduction) with the implementation of AV biofeedback (p-value biofeedback (p-value biofeedback (p-value = 0.012). The diaphragm motion reproducibility improvements with AV biofeedback were consistent with the abdominal motion reproducibility that was observed from the external marker motion variation. Conclusions: This study was the first to investigate the potential of AV biofeedback to improve the motion

Diaphragm and Lung Ultrasound to Predict Weaning Outcome: Systematic Review and Meta-Analysis.

Science.gov (United States)

Llamas-Álvarez, Ana M; Tenza-Lozano, Eva M; Latour-Pérez, Jaime

2017-12-01

Deciding the optimal timing for extubation in patients who are mechanically ventilated can be challenging, and traditional weaning predictor tools are not very accurate. The aim of this systematic review and meta-analysis was to assess the accuracy of lung and diaphragm ultrasound for predicting weaning outcomes in critically ill adults. MEDLINE, the Cochrane Library, Web of Science, Scopus, LILACS, Teseo, Tesis Doctorales en Red, and OpenGrey were searched, and the bibliographies of relevant studies were reviewed. Two researchers independently selected studies that met the inclusion criteria and assessed study quality in accordance with the Quality Assessment of Diagnostic Accuracy Studies-2 tool. The summary receiver-operating characteristic curve and pooled diagnostic OR (DOR) were estimated by using a bivariate random effects analysis. Sources of heterogeneity were explored by using predefined subgroup analyses and bivariate meta-regression. Nineteen studies involving 1,071 people were included in the study. For diaphragm thickening fraction, the area under the summary receiver-operating characteristic curve was 0.87, and DOR was 21 (95% CI, 11-40). Regarding diaphragmatic excursion, pooled sensitivity was 75% (95% CI, 65-85); pooled specificity, 75% (95% CI, 60-85); and DOR, 10 (95% CI, 4-24). For lung ultrasound, the area under the summary receiver-operating characteristic curve was 0.77, and DOR was 38 (95% CI, 7-198). Based on bivariate meta-regression analysis, a significantly higher specificity for diaphragm thickening fraction and higher sensitivity for diaphragmatic excursion was detected in studies with applicability concerns. Lung and diaphragm ultrasound can help predict weaning outcome, but its accuracy may vary depending on the patient subpopulation. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

CFD analysis of a diaphragm free-piston Stirling cryocooler

Science.gov (United States)

Caughley, Alan; Sellier, Mathieu; Gschwendtner, Michael; Tucker, Alan

2016-10-01

This paper presents a Computational Fluid Dynamics (CFD) analysis of a novel free-piston Stirling cryocooler that uses a pair of metal diaphragms to seal and suspend the displacer. The diaphragms allow the displacer to move without rubbing or moving seals. When coupled to a metal diaphragm pressure wave generator, the system produces a complete Stirling cryocooler with no rubbing parts in the working gas space. Initial modelling of this concept using the Sage modelling tool indicated the potential for a useful cryocooler. A proof-of-concept prototype was constructed and achieved cryogenic temperatures. A second prototype was designed and constructed using the experience gained from the first. The prototype produced 29 W of cooling at 77 K and reached a no-load temperature of 56 K. The diaphragm's large diameter and short stroke produces a significant radial component to the oscillating flow fields inside the cryocooler which were not modelled in the one-dimensional analysis tool Sage that was used to design the prototypes. Compared with standard pistons, the diaphragm geometry increases the gas-to-wall heat transfer due to the higher velocities and smaller hydraulic diameters. A Computational Fluid Dynamics (CFD) model of the cryocooler was constructed to understand the underlying fluid-dynamics and heat transfer mechanisms with the aim of further improving performance. The CFD modelling of the heat transfer in the radial flow fields created by the diaphragms shows the possibility of utilizing the flat geometry for heat transfer, reducing the need for, and the size of, expensive heat exchangers. This paper presents details of a CFD analysis used to model the flow and gas-to-wall heat transfer inside the second prototype cryocooler, including experimental validation of the CFD to produce a robust analysis.

Effect of hyperinflation on inspiratory function of the diaphragm.

Science.gov (United States)

Minh, V D; Dolan, G F; Konopka, R F; Moser, K M

1976-01-01

The inspiratory efficiency of the diaphragm during unilateral and bilateral phrenic stimulation (UEPS and BEPS) with constant stimulus was studied in seven dogs from FRC to 120% TLC. Alveolar pressures (PAl) were recorded during relaxation, BEPS and UEPS at each lung volume in the closed respiratory system. From the PAl-lung volume curves, tidal volume (VT), and pressure developed by the diaphragm (Pmus) were derived. Results are summarized below. a) Hyperinflation impaired the inspiratory efficiency of the diaphragm which behaved as an expiratory muscle beyond the lung volume of 103.7% TLC (Vinef). b) The diaphragm during UEPS became expiratory at the same Vinef as during (BEPS. C) The VT-lung volume relationship was linear during BEPS, allowing simple quantitation of VT loss with hyperinflation and prediction of Vinef. d) With only one phrenic nerve stimulated, the functional loss is less pronounced in VT than in Pmus, as compared to BEPS, indicating that the respiratory system was more compliant during UEPS than BEPS. This compliance difference from UEPS to BEPS diminished with severe hyperinflation.

Design and analysis of diaphragms in dynamic microphones

Directory of Open Access Journals (Sweden)

Zi-Gui Huang

2015-07-01

Full Text Available Most contemporary high-end microphones are dynamic microphones, adopting the most basic electromagnetic transduction principles. This study investigated the diaphragm structures of dynamic microphones. The diaphragms were composed of polyimide material, and the boundary settings required for actual operation were provided using finite element model analysis software. The characteristic frequencies caused by grooving variations on the three-dimensional diaphragm were analyzed for the various groove shapes and number. The groove angles and width variations were examined based on the optimal groove shape selected in the aforementioned analysis, and the effects of these shapes were determined based on the analytical results. Acoustic waves cause thin films to vibrate, forming the working principle behind dynamic microphones. The thin film drives a coil to vibrate in a magnetic field and cuts the line of magnetic force, subsequently producing a voltage on both ends of the coil. This audio-frequency-inducted voltage represents an acoustic wave message. The finite element model analysis software was used to conduct electromagnetic induction simulations; the sound source was fed to the diaphragm to drive the coil. The coil vibrations caused the line of magnetic force to be cut, and the final voltages produced were examined and compared.

Crura sign: differentiation between traumatic rupture of the diaphragm and nontraumatic diaphragmatic elevation on CT

International Nuclear Information System (INIS)

Kim, Sung Jin; Han, Hae Ja; Kim, Wang Jung; Youk, Yong Soo; Han, Gi Seok; Cha, Sang Hoon; Park, Kil Sun; Kim, Dae Young

1997-01-01

To evaluate whether in patients with diffuse evaluation of a hemidiaphragm on chest radiographs, the apparence of the crura on CT might be helpful in differentiating between traumatic rupture of the diaphragm (TRD) and nontraumatic causes such as diaphragmatic palsy or diffuse diaphragmatic eventration. Among patients with diffuse elevations of a hemidiaphragm on chest radiograph, 27 who had patients undergone CT scans were retrospectively reviewed. Twelve patients had surgically proven TRD, and 15 had nontraumatic elevation of a hemidiaphragm such as diaphragmatic palsy or diffuse diaphragmatic eventration. Under the hypothesis that the affected crus is markedly thinner than the normal side in nontraumatic elevation but is normal in TRD ('crura sign', we optically assessed without measurement the thickness of both crura. In all patients with TRD, the thickness of the affected crus was similar to that of the contralateral side. In all patients with nontraumatic causes, however, the crus of the elevated hemidiaphragm was markedly thinner than that of the normal side. The 'crura sign' may be useful additional CT finding of traumatic rupture the diaphragm

Design of Diaphragm Based MEMS Pressure Sensor with Sensitivity Analysis for Environmental Applications

Directory of Open Access Journals (Sweden)

A. Nallathambi

2015-05-01

Full Text Available In this paper Micro-electromechanical System (MEMS diaphragm based pressure sensor for environmental applications is discussed. The main focus of this paper is to design, simulate and analyze the sensitivity of MEMS based diaphragm using different structures to measure the low and high pressure values. The simulation is done through the finite element tool and specifications related the maximum convinced stress; deflection and sensitivity of the diaphragms have been analyzed using the software INTELLISUITE 8.7v. The change in pressure is to bending of the diaphragm that modifies the measured displacement between the substrate and the diaphragm. This change in displacement gives the measure of the pressure in that environment. The design of these studies can be used to improve the sensitivity of these devices. Here the diaphragm based pressure sensor produced better displacement, sensitivity and stress output responses are obtained from the square diaphragm. The pressure range from 0.6 MPa to 25 MPa and its maximum displacement is accordingly 59 mm over a pressure range of 0 to 2 MPa. Its sensitivity is therefore 2.35 [10E-12/Pa].

Visual outcomes after lensectomy and iris claw artisan intraocular lens implantation in patients with Marfan syndrome.

Science.gov (United States)

Rabie, Hossein Mohammad; Malekifar, Parviz; Javadi, Mohammad Ali; Roshandel, Danial; Esfandiari, Hamed

2017-08-01

To review our experience with crystalline lens extraction and iris claw Artisan IOL implantation in patients with lens subluxation secondary to Marfan syndrome. A retrospective analysis of 12 eyes of 9 patients with lens subluxation due to Marfan syndrome who underwent crystalline lens removal and Artisan IOL (Ophtec, Groningen, Netherlands) implantation. A questionnaire of pre- and post-operative data, including demographics, pre- and postoperative comorbidities and complications was completed. Patients were evaluated for visual outcome and occurrence of complications. Uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), and spherical equivalents (SE) were compared before and after lens extraction and IOL insertion. The mean age of the participants was 30.03 ± 15.02 years, and mean post-operative follow-up time was 44.5 ± 16.4 months. Mean BCVA also showed a significant improvement from 0.5 ± 0.3 at the baseline to 0.2 ± 0.2 post-operatively (P = 0.006). SE changed significantly from -11.38 ± 1.99 preoperatively to -0.45 ± 1.65 post-operatively (P = 0.003). All eyes had the IOL implanted at desired position. Post-operative complications were retinal detachment in one case and IOL dislocation in another patient. No other complication such as ocular hypertension, angle abnormalities, clinical cystoids macular edema, and corneal decompensation was observed during the follow-up period. Artisan IOL implantation after lens extraction appears to be an attractive alternative for optical correction in cases of Marfan syndrome with ectopia lentis. It confers a significant improvement in visual acuity with reasonable risk profile.

A monitoring device for pressurised-air-driven diaphragm-based artificial heart assist devices

NARCIS (Netherlands)

Hoeben, F.P.; Hoeben, F.P.; de Mul, F.F.M.; Stokkink, J.S.D.; Stokkink, H.S.D.; Koelink, M.H.; Koelink, M.H.; Greve, Jan

1992-01-01

A non-invasive device has been developed to monitor the diaphragm position and the blood flow in artificial heart assist devices equipped with a pressurised-air-driven diaphragm. Light scattering from the diaphragm is used as a mechanism for measuring. Information about the position of several

A method to reduce patient's eye lens dose in neuro-interventional radiology procedures

International Nuclear Information System (INIS)

Safari, M.J.; Wong, J.H.D.; Kadir, K.A.A.; Sani, F.M.; Ng, K.H.

2016-01-01

Complex and prolonged neuro-interventional radiology procedures using the biplane angiography system increase the patient's risk of radiation-induced cataract. Physical collimation is the most effective way of reducing the radiation dose to the patient's eye lens, but in instances where collimation is not possible, an attenuator may be useful in protecting the eyes. In this study, an eye lens protector was designed and fabricated to reduce the radiation dose to the patients’ eye lens during neuro-interventional procedures. The eye protector was characterised before being tested on its effectiveness in a simulated aneurysm procedure on an anthropomorphic phantom. Effects on the automatic dose rate control (ADRC) and image quality are also evaluated. The eye protector reduced the radiation dose by up to 62.1% at the eye lens. The eye protector is faintly visible in the fluoroscopy images and increased the tube current by a maximum of 3.7%. It is completely invisible in the acquisition mode and does not interfere with the clinical procedure. The eye protector placed within the radiation field of view was able to reduce the radiation dose to the eye lens by direct radiation beam of the lateral x-ray tube with minimal effect on the ADRC system. - Highlights: • The eye protector can considerably reduce the patient's eye lens dose during neuro-interventional procedures. • This protector does not significantly perturb the fluoroscopy image and was completely invisible on the acquisition image due to image subtraction. • The eye protector does not significantly change the exposure parameters (kV and mAs).

Plasma Discharge Process in a Pulsed Diaphragm Discharge System

Science.gov (United States)

Duan, Jianjin; Hu, Jue; Zhang, Chao; Wen, Yuanbin; Meng, Yuedong; Zhang, Chengxu

2014-12-01

As one of the most important steps in wastewater treatment, limited study on plasma discharge process is a key challenge in the development of plasma applications. In this study, we focus on the plasma discharge process of a pulsed diaphragm discharge system. According to the analysis, the pulsed diaphragm discharge proceeds in seven stages: (1) Joule heating and heat exchange stage; (2) nucleated site formation; (3) plasma generation (initiation of the breakdown stage); (4) avalanche growth and plasma expansion; (5) plasma contraction; (6) termination of the plasma discharge; and (7) heat exchange stage. From this analysis, a critical voltage criterion for breakdown is obtained. We anticipate this finding will provide guidance for a better application of plasma discharges, especially diaphragm plasma discharges.

TU-E-201-01: Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionists

Energy Technology Data Exchange (ETDEWEB)

Rehani, M. [Massachusetts General Hospital (United States)

2015-06-15

Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bomb survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on

TU-E-201-01: Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionists

International Nuclear Information System (INIS)

Rehani, M.

2015-01-01

Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bomb survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on

Investigation of the Durability of a Diaphragm for a Total Artificial Heart.

Science.gov (United States)

Gräf, Felix; Rossbroich, Ralf; Finocchiaro, Thomas; Steinseifer, Ulrich

2016-10-01

One of the most critical components regarding the durability of the ReinHeart total artificial heart (TAH) is its biocompatible diaphragm, which separates the drive unit from the ventricles. Hence, a durability tester was designed to investigate its required 5-year lifetime. The aim of this study was to prove the validity of accelerated testing of the polyurethane diaphragm. The durability tester allows simultaneous testing of 12 diaphragms and mimics physiological conditions. To accelerate the time of testing, it operates with an increased speed at a frequency of 8 Hz. To prove the correctness of this acceleration, a servo-hydraulic testing machine was used to study the effect of different frequencies and their corresponding loads. Thereby the viscoelastic behavior of the polyurethane was investigated. Additionally, high-speed video measurements were performed. The force against frequency and the high-speed video measurements showed constant behavior. In the range of 1-10 Hz, the maximum resulting forces varied by 3%, and the diaphragm movement was identical. Frequencies below 10 Hz allow a valid statement of the diaphragm's mechanical durability. Viscoelasticity of the polyurethane in the considered frequency-range is negligible. The accelerated durability test is applicable to polyurethane diaphragms, and the results are applicable to TAH use. The reliability of the diaphragm for a lifetime of 5 years was found to be 80% with a confidence of 62%. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Phrenic nerves and diaphragms in sudden infant death syndrome.

Science.gov (United States)

Weis, J; Weber, U; Schröder, J M; Lemke, R; Althoff, H

1998-01-30

Disturbances of the respiratory system may be an important factor in the cascade of events leading to sudden infant death syndrome (SIDS). Even though the diaphragm is the major respiratory muscle in infants, little is known about alterations of this muscle and of the phrenic nerve in SIDS. In the present study, diaphragms and phrenic nerves of 24 SIDS infants and seven controls were analyzed. Morphometric analysis revealed only slightly larger cross sectional areas of phrenic nerve axons but no increase in myelin sheath thickness in SIDS cases. However, in one SIDS case, myelinated nerve fibre density was severely reduced. Using electron microscopy, several nerve fibres of SIDS infants showed focal accumulations of neurofilaments. Muscle fibre diameters in SIDS diaphragms were significantly larger compared to controls (P fibre ruptures and contracture bands were found. These prominent nonspecific ultrastructural alterations should advise caution in the interpretation of morphometric data. Thus, in some cases exemplified by one case of the present series, decreased density of phrenic nerve myelinated axons might contribute to SIDS. Still, the present results indicate that development of phrenic nerves and diaphragms is not delayed in most SIDS infants.

The Effect of the Crystalline Lens on Central Vault After Implantable Collamer Lens Implantation.

Science.gov (United States)

Qi, Meng-Ying; Chen, Qian; Zeng, Qing-Yan

2017-08-01

To identify associations between crystalline lens-related factors and central vault after Implantable Collamer Lens (ICL) (Staar Surgical, Monrovia, CA) implantation. This retrospective clinical study included 320 eyes from 186 patients who underwent ICL implantation surgery. At 1 year after surgery, the central vault was measured using anterior segment optical coherence tomography. Preoperative anterior chamber depth, lens thickness, lens position (lens position = anterior chamber depth + 1/2 lens thickness), and vault were analyzed to investigate the effects of lens-related factors on postoperative vault. The mean vault was 513 ± 215 µm at 1 year after surgery. Vault was positively correlated with preoperative anterior chamber depth (r = 0.495, P lens position (r = 0.371, P lens thickness (r = -0.262, P lens position than eyes in the other two vault groups (which had vaults ≥ 250 µm) (P lens position less than 5.1 mm had greatly reduced vaults (P lens could have an important influence on postoperative vault. Eyes with a shallower anterior chamber and a forward lens position will have lower vaults. [J Refract Surg. 2017;33(8):519-523.]. Copyright 2017, SLACK Incorporated.

DOUBLE BOSS SCULPTURED DIAPHRAGM EMPLOYED PIEZORESISTIVE MEMS PRESSURE SENSOR WITH SILICON-ON-INSULATOR (SOI

Directory of Open Access Journals (Sweden)

D. SINDHANAISELVI

2017-07-01

Full Text Available This paper presents the detailed study on the measurement of low pressure sensor using double boss sculptured diaphragm of piezoresistive type with MEMS technology in flash flood level measurement. The MEMS based very thin diaphragms to sense the low pressure is analyzed by introducing supports to achieve linearity. The simulation results obtained from Intellisuite MEMS CAD design tool show that very thin diaphragms with rigid centre or boss give acceptable linearity. Further investigations on very thin diaphragms embedded with piezoresistor for low pressure measurement show that it is essential to analyse the piezoresistor placement and size of piezoresistor to achieve good sensitivity. A modified analytical modelling developed in this study for double boss sculptured diaphragm results were compared with simulated results. Further the enhancement of sensitivity is analyzed using non uniform thickness diaphragm and Silicon-On-Insulator (SOI technique. The simulation results indicate that the double boss square sculptured diaphragm with SOI layer using 0.85μm thickness yields the higher voltage sensitivity, acceptable linearity with Small Scale Deflection.

Automatic assessment of average diaphragm motion trajectory from 4DCT images through machine learning.

Science.gov (United States)

Li, Guang; Wei, Jie; Huang, Hailiang; Gaebler, Carl Philipp; Yuan, Amy; Deasy, Joseph O

2015-12-01

To automatically estimate average diaphragm motion trajectory (ADMT) based on four-dimensional computed tomography (4DCT), facilitating clinical assessment of respiratory motion and motion variation and retrospective motion study. We have developed an effective motion extraction approach and a machine-learning-based algorithm to estimate the ADMT. Eleven patients with 22 sets of 4DCT images (4DCT1 at simulation and 4DCT2 at treatment) were studied. After automatically segmenting the lungs, the differential volume-per-slice (dVPS) curves of the left and right lungs were calculated as a function of slice number for each phase with respective to the full-exhalation. After 5-slice moving average was performed, the discrete cosine transform (DCT) was applied to analyze the dVPS curves in frequency domain. The dimensionality of the spectrum data was reduced by using several lowest frequency coefficients ( f v ) to account for most of the spectrum energy (Σ f v 2 ). Multiple linear regression (MLR) method was then applied to determine the weights of these frequencies by fitting the ground truth-the measured ADMT, which are represented by three pivot points of the diaphragm on each side. The 'leave-one-out' cross validation method was employed to analyze the statistical performance of the prediction results in three image sets: 4DCT1, 4DCT2, and 4DCT1 + 4DCT2. Seven lowest frequencies in DCT domain were found to be sufficient to approximate the patient dVPS curves ( R = 91%-96% in MLR fitting). The mean error in the predicted ADMT using leave-one-out method was 0.3 ± 1.9 mm for the left-side diaphragm and 0.0 ± 1.4 mm for the right-side diaphragm. The prediction error is lower in 4DCT2 than 4DCT1, and is the lowest in 4DCT1 and 4DCT2 combined. This frequency-analysis-based machine learning technique was employed to predict the ADMT automatically with an acceptable error (0.2 ± 1.6 mm). This volumetric approach is not affected by the presence of the lung tumors

The diaphragms of fenestrated endothelia: gatekeepers of vascular permeability and blood composition.

Science.gov (United States)

Stan, Radu V; Tse, Dan; Deharvengt, Sophie J; Smits, Nicole C; Xu, Yan; Luciano, Marcus R; McGarry, Caitlin L; Buitendijk, Maarten; Nemani, Krishnamurthy V; Elgueta, Raul; Kobayashi, Takashi; Shipman, Samantha L; Moodie, Karen L; Daghlian, Charles P; Ernst, Patricia A; Lee, Hong-Kee; Suriawinata, Arief A; Schned, Alan R; Longnecker, Daniel S; Fiering, Steven N; Noelle, Randolph J; Gimi, Barjor; Shworak, Nicholas W; Carrière, Catherine

2012-12-11

Fenestral and stomatal diaphragms are endothelial subcellular structures of unknown function that form on organelles implicated in vascular permeability: fenestrae, transendothelial channels, and caveolae. PV1 protein is required for diaphragm formation in vitro. Here, we report that deletion of the PV1-encoding Plvap gene in mice results in the absence of diaphragms and decreased survival. Loss of diaphragms did not affect the fenestrae and transendothelial channels formation but disrupted the barrier function of fenestrated capillaries, causing a major leak of plasma proteins. This disruption results in early death of animals due to severe noninflammatory protein-losing enteropathy. Deletion of PV1 in endothelium, but not in the hematopoietic compartment, recapitulates the phenotype of global PV1 deletion, whereas endothelial reconstitution of PV1 rescues the phenotype. Taken together, these data provide genetic evidence for the critical role of the diaphragms in fenestrated capillaries in the maintenance of blood composition. Copyright © 2012 Elsevier Inc. All rights reserved.

Free-Standing β-Ga2O3 Thin Diaphragms

Science.gov (United States)

Zheng, Xu-Qian; Lee, Jaesung; Rafique, Subrina; Han, Lu; Zorman, Christian A.; Zhao, Hongping; Feng, Philip X.-L.

2018-02-01

Free-standing, very thin, single-crystal β-gallium oxide (β-Ga2O3) diaphragms have been constructed and their dynamical mechanical properties characterized by noncontact, noninvasive optical measurements harnessing the multimode nanomechanical resonances of these suspended nanostructures. We synthesized single-crystal β-Ga2O3 using low-pressure chemical vapor deposition (LPCVD) on a 3C-SiC epilayer grown on Si substrate at temperature of 950°C for 1.5 h. The synthesized single-crystal nanoflakes had widths of ˜ 2 μm to 30 μm and thicknesses of ˜ 20 nm to 140 nm, from which we fabricated free-standing circular drumhead β-Ga2O3 diaphragms with thicknesses of ˜ 23 nm to 73 nm and diameters of ˜ 3.2 μm and ˜ 5.2 μm using a dry stamp-transfer technique. Based on measurements of multiple flexural-mode mechanical resonances using ultrasensitive laser interferometric detection and performing thermal annealing at 250°C for 1.5 h, we quantified the effects of annealing and adsorption of atmospheric gas molecules on the resonant characteristics of the diaphragms. Furthermore, we studied the effects of structural nonidealities on these free-standing β-Ga2O3 nanoscale diaphragms. We present extensive characterization of the mechanical and optical properties of free-standing β-Ga2O3 diaphragms, paving the way for realization of resonant transducers using such nanomechanical structures for use in applications including gas sensing and ultraviolet radiation detection.

Continuity diaphragm for skewed continuous span precast prestressed concrete girder bridges.

Science.gov (United States)

2004-10-01

Continuity diaphragms used on skewed bents in prestressed girder bridges cause difficulties in detailing and : construction. Details for bridges with large diaphragm skew angles (>30) have not been a problem for LA DOTD. : However, as the skew angl...

Numerical investigation on vibration characteristics of a micro-speaker diaphragm considering thermoforming effects

Energy Technology Data Exchange (ETDEWEB)

Kim, Kyeong Min; Park, Ke Un [Seoul National University of Science and Technology, Seoul (Korea, Republic of)

2013-10-15

Micro-speaker diaphragms play an important role in generating desired sound responses, and are designed to have thin membrane shapes for flexibility in the axial direction. The micro-speaker diaphragms are formed from thin polymer film through the thermoforming process, in which local thickness reductions occur due to strain localization. This thickness reduction results in a change in vibration characteristics of the diaphragm and different sound responses from that of the original design. In this study, the effect of this thickness change in the diaphragm on its vibration characteristics is numerically investigated by coupling thermoforming simulation, structural analysis and modal analysis. Thus, the thickness change in the diaphragm is calculated from the thermoforming simulation, and reflected in the further structural and modal analyses in order to estimate the relevant stiffness and vibration modes. Comparing these simulation results with those from a diaphragm with the uniform thickness, it is found that a local thickness reduction results in the stiffness reduction and the relevant change in the natural frequencies and the corresponding vibration modes.

Numerical investigation on vibration characteristics of a micro-speaker diaphragm considering thermoforming effects

International Nuclear Information System (INIS)

Kim, Kyeong Min; Park, Ke Un

2013-01-01

Micro-speaker diaphragms play an important role in generating desired sound responses, and are designed to have thin membrane shapes for flexibility in the axial direction. The micro-speaker diaphragms are formed from thin polymer film through the thermoforming process, in which local thickness reductions occur due to strain localization. This thickness reduction results in a change in vibration characteristics of the diaphragm and different sound responses from that of the original design. In this study, the effect of this thickness change in the diaphragm on its vibration characteristics is numerically investigated by coupling thermoforming simulation, structural analysis and modal analysis. Thus, the thickness change in the diaphragm is calculated from the thermoforming simulation, and reflected in the further structural and modal analyses in order to estimate the relevant stiffness and vibration modes. Comparing these simulation results with those from a diaphragm with the uniform thickness, it is found that a local thickness reduction results in the stiffness reduction and the relevant change in the natural frequencies and the corresponding vibration modes.

[Congenital lens subluxation: visual acuity outcomes and intraocular lens postoperative position].

Science.gov (United States)

Arraes, Caroline; Endriss, Daniela; Lobato, Francisco; Arraes, João; Ventura, Marcelo

2010-01-01

To evaluate the visual acuity outcomes and to investigate the intraocular lens (IOL) and endocapsular ring positions with ultrasound biomicroscopy in 17 eyes of 10 patients with congenital lens subluxation who underwent the same surgical technique, by the same surgeon. The study was performed in the ''Hospital de Olhos de Pernambuco'' and ''Fundação Altino Ventura''. The surgical technique consisted of phacoaspiration with implant of endocapsular ring and intraocular lens with one loop haptic amputated. The age varied from 7 to 22 years. Data on visual acuity (VA) before and after surgery, surgery follow-up period, and complications were analyzed. All patients underwent ultrasound biomicroscopy. The mean follow-up period was 2.8 years. There was a VA improvement in 17 (100%) eyes: in 12 eyes (70.6%) the visual acuity was better than 20/40; 4 (23.5%) ranged from 20/40 to 20/100, and 1 (5.9%) had visual acuity worse than 20/100, however better than the preoperative visual acuity. The posterior capsular opacification occurred in 10 eyes (58.9%). Ultrasound biomicroscopy showed that all IOL were partially decentralized, however without surpassing the pupil border limit. Endocapsular ring position was correct and there was a good capsular support in all cases. The evaluated surgical treatment provided good intraocular lens and endocapsular ring position, with VA improvement Thus, this technique is a viable, effective and safe option for the visual rehabilitation of patients with congenital lens subluxation.

Failure analysis of globe control valves with spring-diaphragm actuator for nuclear power plant applications

International Nuclear Information System (INIS)

Khan, M.R.; Chen, W.W.H.; Wang, T.Y.

1997-01-01

The results of the failure analysis of a globe control valve with spring-diaphragm actuator indicated that the diaphragm failed because the service loading is close to the strength of the diaphragm. The resulting impact force is significantly larger than the plug guide strength and that cause it to bulge out after the impact. To improve the valve performance, proper torque should be used to tighten the actuator diaphragm case fasteners. A stronger actuator diaphragm could be used to provide additional safety margin during operation. Stiffening the plug guide may avoid jamming the bushing

Multiple methods of surgical treatment combined with primary IOL implantation on traumatic lens subluxation/dislocation in patients with secondary glaucoma

OpenAIRE

Wang, Rui; Bi, Chun-Chao; Lei, Chun-Ling; Sun, Wen-Tao; Wang, Shan-Shan; Dong, Xiao-Juan

2014-01-01

AIM:To describe clinical findings and complications from cases of traumatic lens subluxation/dislocation in patients with secondary glaucoma, and discuss the multiple treating methods of operation combined with primary intraocular lens (IOL) implantation.METHODS:Non-comparative retrospective observational case series. Participants:30 cases (30 eyes) of lens subluxation/dislocation in patients with secondary glaucoma were investigated which accepted the surgical treatment by author in the Opht...

Novel diaphragm for electrolytic cells. Final report

International Nuclear Information System (INIS)

The basic intent of these studies is to produce a diaphragm permeable to two types of ions, which have properties which are similar to those of asbestos. PTFE in the form of fabric is rendered hydrophilic by grafting monomer acrylic acid by a radio-chemical technique; two methods were utilized to do this: - Direct radio-chemical method under radiation - Pre-irradiation method in air under radiation and accelerated electronic radiation. The monomer acrylic acid was grafted in the presence or non-presence of cross-linking agents, the latter before developing a resistance derived from the diaphragms obtained at the agressivity of the medium in which they would be utilized

Investigation of PVdF active diaphragms for synthetic jets

Science.gov (United States)

Bailo, Kelly C.; Brei, Diann E.; Calkins, Frederick T.

2000-06-01

Current research has shown that aircraft can gain significant aerodynamic performance benefits by employing active flow control (AFC). One of the enabling technologies of AFC is the synthetic jet. Synthetic jets, also known as zero-net-mass flux actuators, act as bi-directional pumps injecting high momentum air into the local aerodynamic flow. Previous work has concentrated on high frequency synthetic jets based on piezoelectric active diaphragms such as Thunder actuators. Low frequency synthetic jets present a unique challenge requiring large displacements, which current technology has difficulty meeting. Boeing is investigating novel shaped low frequency synthetic jets that can modify the flow over fixed aircraft wings. This paper present the initial study of two promising active diaphragm concepts: a crescent shape and an opposing bender shape. These active diaphragms were numerically modeled utilizing the general-purpose finite element code ABAQUS. Using the ABAQUS results, the dynamic volume change within each jet was calculated and incorporated into an analytical linear Bernoulli model to predict the velocities and pressures at the nozzle. Simulations were performed to determine trends to assist in selection of prototype configurations. Prototypes of both diaphragm concepts were constructed from polyvinylidene fluoride and experimentally tested at Boeing with promising results.

Diaphragm Pump With Resonant Piezoelectric Drive

Science.gov (United States)

Izenson, Michael G.; Kline-Schoder, Robert J.; Shimko, Martin A.

2007-01-01

A diaphragm pump driven by a piezoelectric actuator is undergoing development. This pump is intended to be a prototype of lightweight, highly reliable pumps for circulating cooling liquids in protective garments and high-power electronic circuits, and perhaps for some medical applications. The pump would be highly reliable because it would contain no sliding seals or bearings that could wear, the only parts subject to wear would be two check valves, and the diaphragm and other flexing parts could be designed, by use of proven methods, for extremely long life. Because the pump would be capable of a large volumetric flow rate and would have only a small dead volume, its operation would not be disrupted by ingestion of gas, and it could be started reliably under all conditions. The prior art includes a number piezoelectrically actuated diaphragm pumps. Because of the smallness of the motions of piezoelectric actuators (typical maximum strains only about 0.001), the volumetric flow rates of those pumps are much too small for typical cooling applications. In the pump now undergoing development, mechanical resonance would be utilized to amplify the motion generated by the piezoelectric actuator and thereby multiply the volumetric flow rate. The prime mover in this pump would be a stack of piezoelectric ceramic actuators, one end of which would be connected to a spring that would be part of a spring-and-mass resonator structure. The mass part of the resonator structure would include the pump diaphragm (see Figure 1). Contraction of the spring would draw the diaphragm to the left, causing the volume of the fluid chamber to increase and thereby causing fluid to flow into the chamber. Subsequent expansion of the spring would push the diaphragm to the right, causing the volume of the fluid chamber to decrease, and thereby expelling fluid from the chamber. The fluid would enter and leave the chamber through check valves. The piezoelectric stack would be driven electrically to

Stylus type MEMS texture sensor covered with corrugated diaphragm

Science.gov (United States)

Tsukamoto, Takashiro; Asao, Hideaki; Tanaka, Shuji

2017-09-01

In this paper, a stylus type MEMS texture sensor covered with a corrugated palylene diaphragm, which prevent debris from jamming into the sensor without significant degradation of sensitivity and bandwidth, was reported. A new fabrication process using a lost-foil method to make the corrugated diaphragm on a 3-axis piezoresistive force sensor at wafer level has been developed. The texture sensor could detect the surface microstructure as small as about 10 \

Internally-cooled centrifugal compressor with cooling jacket formed in the diaphragm

Science.gov (United States)

Moore, James J.; Lerche, Andrew H.; Moreland, Brian S.

2014-08-26

An internally-cooled centrifugal compressor having a shaped casing and a diaphragm disposed within the shaped casing having a gas side and a coolant side so that heat from a gas flowing though the gas side is extracted via the coolant side. An impeller disposed within the diaphragm has a stage inlet on one side and a stage outlet for delivering a pressurized gas to a downstream connection. The coolant side of the diaphragm includes at least one passageway for directing a coolant in a substantially counter-flow direction from the flow of gas through the gas side.

Computer simulation analysis of normal and abnormal development of the mammalian diaphragm

Science.gov (United States)

Fisher, Jason C; Bodenstein, Lawrence

2006-01-01

Background Congenital diaphragmatic hernia (CDH) is a birth defect with significant morbidity and mortality. Knowledge of diaphragm morphogenesis and the aberrations leading to CDH is limited. Although classical embryologists described the diaphragm as arising from the septum transversum, pleuroperitoneal folds (PPF), esophageal mesentery and body wall, animal studies suggest that the PPF is the major, if not sole, contributor to the muscular diaphragm. Recently, a posterior defect in the PPF has been identified when the teratogen nitrofen is used to induce CDH in fetal rodents. We describe use of a cell-based computer modeling system (Nudge++™) to study diaphragm morphogenesis. Methods and results Key diaphragmatic structures were digitized from transverse serial sections of paraffin-embedded mouse embryos at embryonic days 11.5 and 13. Structure boundaries and simulated cells were combined in the Nudge++™ software. Model cells were assigned putative behavioral programs, and these programs were progressively modified to produce a diaphragm consistent with the observed anatomy in rodents. Homology between our model and recent anatomical observations occurred under the following simulation conditions: (1) cell mitoses are restricted to the edge of growing tissue; (2) cells near the chest wall remain mitotically active; (3) mitotically active non-edge cells migrate toward the chest wall; and (4) movement direction depends on clonal differentiation between anterior and posterior PPF cells. Conclusion With the PPF as the sole source of mitotic cells, an early defect in the PPF evolves into a posteromedial diaphragm defect, similar to that of the rodent nitrofen CDH model. A posterolateral defect, as occurs in human CDH, would be more readily recreated by invoking other cellular contributions. Our results suggest that recent reports of PPF-dominated diaphragm morphogenesis in the rodent may not be strictly applicable to man. The ability to recreate a CDH defect

Computer simulation analysis of normal and abnormal development of the mammalian diaphragm

Directory of Open Access Journals (Sweden)

Bodenstein Lawrence

2006-02-01

Full Text Available Abstract Background Congenital diaphragmatic hernia (CDH is a birth defect with significant morbidity and mortality. Knowledge of diaphragm morphogenesis and the aberrations leading to CDH is limited. Although classical embryologists described the diaphragm as arising from the septum transversum, pleuroperitoneal folds (PPF, esophageal mesentery and body wall, animal studies suggest that the PPF is the major, if not sole, contributor to the muscular diaphragm. Recently, a posterior defect in the PPF has been identified when the teratogen nitrofen is used to induce CDH in fetal rodents. We describe use of a cell-based computer modeling system (Nudge++™ to study diaphragm morphogenesis. Methods and results Key diaphragmatic structures were digitized from transverse serial sections of paraffin-embedded mouse embryos at embryonic days 11.5 and 13. Structure boundaries and simulated cells were combined in the Nudge++™ software. Model cells were assigned putative behavioral programs, and these programs were progressively modified to produce a diaphragm consistent with the observed anatomy in rodents. Homology between our model and recent anatomical observations occurred under the following simulation conditions: (1 cell mitoses are restricted to the edge of growing tissue; (2 cells near the chest wall remain mitotically active; (3 mitotically active non-edge cells migrate toward the chest wall; and (4 movement direction depends on clonal differentiation between anterior and posterior PPF cells. Conclusion With the PPF as the sole source of mitotic cells, an early defect in the PPF evolves into a posteromedial diaphragm defect, similar to that of the rodent nitrofen CDH model. A posterolateral defect, as occurs in human CDH, would be more readily recreated by invoking other cellular contributions. Our results suggest that recent reports of PPF-dominated diaphragm morphogenesis in the rodent may not be strictly applicable to man. The ability to

Effect of Elastase-induced Emphysema on the Force-generating Ability of the Diaphragm

Science.gov (United States)

Supinski, Gerald S.; Kelsen, Steven G.

1982-01-01

The effect of emphysema on the ability of the diaphragm to generate force was examined in costal diaphragm muscle strips from 10 Golden hamsters killed 18 mo after intratracheal injection of pancreatic elastase in a dose producing hyperinflation (mean total lung capacity [TLC] = 163% of control) and generalized panacinar emphysema. 13 saline-injected normal animals served as controls. The time course of isometric tension and the effect of alterations in muscle fiber and sarcomere length on the isometric tension (T) generated in response to tetanizing electrical stimuli (length-tension [L-T] relationship) were examined. Elastase administration caused an increase in diaphragm muscle thickness and reduction in the length of costal diaphragm muscle fibers measured in situ. Emphysema significantly increased the maximum tetanic tension as a result of hypertrophy. Maximal tension corrected for increases in muscle cross-sectional area (T/cm2), however, was the same in emphysematous (E) and control (C) animals. Emphysema also shifted the muscle fiber L-T curve of the diaphragm but not of a control muscle, the soleus, toward shorter lengths. In contrast to the effects of E on the diaphragm muscle fiber L-T curve, the sarcomere L-T curve was the same in E and C. Since the length at which tension was maximal correlated closely with sarcomere number (r = 0.94; P < 0.001) reduction in the number of sarcomeres in series in muscles from emphysematous animals appeared to explain the shift in the muscle fiber L-T curve. We conclude that in elastase-induced emphysema adaptive changes both in diaphragm cross-sectional area and sarcomere number augment the force-generating ability of the diaphragm. We speculate that changes in sarcomere number compensate for alterations in muscle fiber length resulting from chronic hyperinflation of the thorax, while diaphragmatic muscle hypertrophy represents a response to changes in respiratory load and/or diaphragm configuration (La

Ultrasonographic assessment of the diaphragm in chronic obstructive pulmonary disease patients: relationships with pulmonary function and the influence of body composition - a pilot study.

Science.gov (United States)

Smargiassi, Andrea; Inchingolo, Riccardo; Tagliaboschi, Linda; Di Marco Berardino, Alessandro; Valente, Salvatore; Corbo, Giuseppe Maria

2014-01-01

Skeletal muscle weakness with loss of fat-free mass (FFM) is one of the main systemic effects of chronic obstructive pulmonary disease (COPD). The diaphragm is also involved, leading to disadvantageous conditions and poor contractile capacities. We measured the thickness of the diaphragm (TD) by ultrasonography to evaluate the relationships between echographic measurements, parameters of respiratory function and body composition data. Thirty-two patients (23 males) underwent (1) pulmonary function tests, (2) echographic assessment of TD in the zone of apposition at various lung volumes, i.e. TD at residual volume (TDRV), TD at functional residual capacity (TDFRC) and TD at total lung capacity (TDTLC), and (3) bioelectrical body impedance analysis. The BMI and the BODE (BMI-Obstruction-Dyspnea-Exercise) index values were reported. TDRV, TDFRC and TDTLC measured 3.3, 3.6 and 6 mm, respectively, with good intraobserver reproducibility (0.97, 0.97 and 0.96, respectively). All the TDs were found to be related to FFM, with the relationship being greater for TDFRC (r(2) = 0.39 and p = 0.0002). With regard to lung volumes, inspiratory capacity (IC) was found to be closely related to TDTLC (r(2) = 0.42 and p = 0.0001). The difference between TDTLC and TDRV, as a thickening value (TDTLCRV), was closely related to FVC (r(2) = 0.34 and p = 0.0004) and to air-trapping indices (RV/TLC, FRC/TLC and IC/TLC): the degree of lung hyperinflation was greater and the TDTLCRV was less. Finally, we found a progressive reduction of both thicknesses and thickenings as the severity of IC/TLC increased, with a significant p value for the trend in both analyses (p = 0.02). Ultrasonographic assessment of the diaphragm could be a useful tool for studying disease progression in COPD patients, in terms of lung hyperinflation and the loss of FFM. © 2014 S. Karger AG, Basel.

Dystrophic phenotype improvement in the diaphragm muscle of mdx mice by diacerhein.

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Rafael Dias Mâncio

Full Text Available Chronic inflammation and oxidative stress are striking features of Duchenne muscular dystrophy disease. Diacerhein is an anthraquinone, which exhibits anti-inflammatory and antioxidant properties. Based on their actions, the present study evaluated the effects of diacerhein against myonecrosis, oxidative stress and inflammatory response in the diaphragm muscle of mdx mice and compared these results to current treatment widely used in DMD patients, with a main focus on the impact of prednisone. The results demonstrated that diacerhein treatment prevented muscle damage indicated by a decrease in the IgG uptake by muscle fibers, lower CK levels in serum, reduction of fibers with central nuclei with a concomitant increase in fibers with peripheral nuclei. It also had an effect on the inflammatory process, decreasing the inflammatory area, macrophage staining and TNF-α and IL-1β content. Regarding oxidative stress, diacerhein treatment was effective in reducing the ROS and lipid peroxidation in the diaphragm muscle from mdx mice. Compared to prednisone treatment, our findings demonstrated that diacerhein treatment improved the dystrophic phenotype in the diaphragm muscle of mdx mice similar to that of glucocorticoid therapy. In this respect, this work suggests that diacerhein has a potential use as an alternative drug in dystrophinopathy treatment and recommends that its anti-inflammatory and antioxidants properties in the dystrophic muscle should be better understood.

Diaphragm disease of the small intestine: an interesting case report.

Science.gov (United States)

Ullah, Sana; Ajab, Shereen; Rao, Rajashekhar; Raghunathan, Girish; DaCosta, Philip

2015-06-01

Diaphragm disease of small intestine usually presents with nonspecific clinical features. Radiological investigations often fail to differentiate it from small intestinal tumors and inflammatory bowel disease. It is therefore diagnosed on final histology after surgical resection. We hereby report an interesting case of a suspected small bowel tumor later diagnosed as diaphragm disease on histology. © The Author(s) 2014.

The mechanism of transient myopia induced by sulfonamide therapy.

Science.gov (United States)

Bovino, J A; Marcus, D F

1982-07-01

We performed acute and convalescent A-scan echographic ocular measurements documenting the anterior chamber depth, lens thickness, and axial length of a patient with acute transient sulfamethoxazole-induced myopia. Shallowing of the anterior chamber, independent of changes in the thickness of the lens, was the only anatomic variation found that could explain the myopia. Swelling of the ciliary body, with forward movement of the lens-iris diaphragm, could produce this transient anatomic change.

Radiation dose to the lens and cataract formation

International Nuclear Information System (INIS)

Henk, J.M.; Whitelocke, R.A.F.; Warrington, A.P.; Bessell, E.M.

1993-01-01

The purpose of this work was to determine the radiation tolerance of the lens of the eye and the incidence of radiation-induced lens changes in patients treated by fractionated supervoltage radiation therapy for orbital tumors. Forty patients treated for orbital lymphoma and pseudotumor with tumor doses of 20--40 Gy were studied. The lens was partly shielded using lead cylinders in most cases. The dose to the germinative zone of the lens was estimated by measurements in a tissue equivalent phantom using both film densitometry and thermoluminescent dosimetry. Opthalmological examination was performed at 6 monthly intervals after treatment. The lead shield was found to reduce the dose to the germinative zone of the lens to between 36--50% of the tumor dose for Cobalt beam therapy, and to between 11--18% for 5 MeV x-rays. Consequently, the lens doses were in the range 4.5--30 Gy in 10--20 fractions. Lens opacities first appeared from between 3 and 9 years after irradiation. Impairment of visual acuity ensued in 74% of the patients who developed lens opacities. The incidence of lens changes was strongly dose-related. None was seen after doses of 5 Gy or lower, whereas doses of 16.5 Gy or higher were all followed by lens opacities which impaired visual acuity. The largest number of patients received a maximum lens dose of 15 Gy; in this group the actuarial incidence of lens opacities at 8 years was 57% with visual impairment in 38%. The adult lens can tolerate a total dose of 5 Gy during a fractionated course of supervoltage radiation therapy without showing any changes. Doses of 16.5 Gy or higher will almost invariably lead to visual impairment. The dose which causes a 50% probability of visual impairment is approximately 15 Gy. 10 refs., 4 figs., 1 tab

A free-piston Stirling cryocooler using metal diaphragms

Science.gov (United States)

Caughley, Alan; Sellier, Mathieu; Gschwendtner, Michael; Tucker, Alan

2016-12-01

A novel concept for a free-piston Stirling cryocooler has been proposed. The concept uses a pair of metal diaphragms to seal and suspend the displacer of a free-piston Stirling cryocooler. The diaphragms allow the displacer to move without rubbing or moving seals, potentially resulting in a long-life mechanism. When coupled to a metal diaphragm pressure wave generator, the system produces a complete Stirling cryocooler with no rubbing parts in the working gas space. Initial modelling of this concept using the Sage modelling tool indicates the potential for a useful cryocooler. A proof-of-concept prototype was constructed and achieved cryogenic temperatures. A second prototype was designed and constructed using the experience gained from the first. The prototype produced 29 W of cooling at 77 K and reached a no-load temperature of 56 K. Sage predicted the macroscopic behaviour of the prototype well but did not provide sufficient insights to improve performance significantly. This paper presents details of the development, modelling and testing of the proof-of-concept prototype and a second, improved prototype.

[Intraocular lens implantation with one loop haptic amputated: a new propose to the subluxation lens surgical treatment].

Science.gov (United States)

Ventura, Marcelo; Endriss, Daniela

2010-01-01

To evaluate the postoperative results of congenital lens subluxation corrected by a new technique. Retrospective chart review of 21 eyes of 13 patients with no traumatic lens subluxation who underwent surgery in Altino Ventura Foundation from April, 1999 to April, 2004. The mean age was 8.7 +/- 5.4 years old, and the mean follow-up period was 21.5 +/- 19.3 months. Patients underwent phacoaspiration, endocapsular ring and intraocular lens (IOL) implantation. The implanted IOL had one loop haptic excised and was supported above the ring, inside the capsular bag promoting intraocular lens centralization. Visual acuity improvement was observed in all cases. There was a significant reduction of the spherical equivalent and spherical component comparing the pre and postoperative refraction (psubluxation surgical treatment, promoting lens centralization and postoperative visual acuity improvement.

High-intensity interval training prevents oxidant-mediated diaphragm muscle weakness in hypertensive mice.

Science.gov (United States)

Bowen, T Scott; Eisenkolb, Sophia; Drobner, Juliane; Fischer, Tina; Werner, Sarah; Linke, Axel; Mangner, Norman; Schuler, Gerhard; Adams, Volker

2017-01-01

Hypertension is a key risk factor for heart failure, with the latter characterized by diaphragm muscle weakness that is mediated in part by increased oxidative stress. In the present study, we used a deoxycorticosterone acetate (DOCA)-salt mouse model to determine whether hypertension could independently induce diaphragm dysfunction and further investigated the effects of high-intensity interval training (HIIT). Sham-treated (n = 11), DOCA-salt-treated (n = 11), and DOCA-salt+HIIT-treated (n = 15) mice were studied over 4 wk. Diaphragm contractile function, protein expression, enzyme activity, and fiber cross-sectional area and type were subsequently determined. Elevated blood pressure confirmed hypertension in DOCA-salt mice independent of HIIT (P HIIT. Myosin heavy chain (MyHC) protein expression tended to decrease (∼30%; P = 0.06) in DOCA-salt vs. sham- and DOCA-salt+HIIT mice, whereas oxidative stress increased (P HIIT further prevented direct oxidant-mediated diaphragm contractile dysfunction (P hypertension induces diaphragm contractile dysfunction via an oxidant-mediated mechanism that is prevented by HIIT.-Bowen, T. S., Eisenkolb, S., Drobner, J., Fischer, T., Werner, S., Linke, A., Mangner, N., Schuler, G., Adams, V. High-intensity interval training prevents oxidant-mediated diaphragm muscle weakness in hypertensive mice. © FASEB.

Refractive lens exchange with a multifocal diffractive aspheric intraocular lens

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Teresa Ferrer-Blasco

2012-06-01

Full Text Available PURPOSE: To evaluate the safety, efficacy and predictability after refractive lens exchange with multifocal diffractive aspheric intraocular lens implantation. METHODS: Sixty eyes of 30 patients underwent bilateral implantation with AcrySof® ReSTOR® SN6AD3 intraocular lens with +4.00 D near addition. Patients were divided into myopic and hyperopic groups. Monocular best corrected visual acuity at distance and near and monocular uncorrected visual acuity at distance and near were measured before and 6 months postoperatively. RESULTS: After surgery, uncorrected visual acuity was 0.08 ± 0.15 and 0.11 ± 0.14 logMAR for the myopic and hyperopic groups, respectively (50% and 46.67% of patients had an uncorrected visual acuity of 20/20 or better in the myopic and hyperopic groups, respectively. The safety and efficacy indexes were 1.05 and 0.88 for the myopic and 1.01 and 0.86 for the hyperopic groups at distance vision. Within the myopic group, 20 eyes remained unchanged after the surgery, and 3 gained >2 lines of best corrected visual acuity. For the hyperopic group, 2 eyes lost 2 lines of best corrected visual acuity, 21 did not change, and 3 eyes gained 2 lines. At near vision, the safety and efficacy indexes were 1.23 and 1.17 for the myopic and 1.16 and 1.13 for the hyperopic groups. Best corrected near visual acuity improved after surgery in both groups (from 0.10 logMAR to 0.01 logMAR in the myopic group, and from 0.10 logMAR to 0.04 logMAR in the hyperopic group. CONCLUSIONS: The ReSTOR® SN6AD3 intraocular lens in refractive lens exchange demonstrated good safety, efficacy, and predictability in correcting high ametropia and presbyopia.

A Randomized Controlled Trial of Tong Len Meditation Practice in Cancer Patients: Evaluation of a Distant Psychological Healing Effect.

Science.gov (United States)

Pagliaro, Gioacchino; Pandolfi, Paolo; Collina, Natalina; Frezza, Giovanni; Brandes, Alba; Galli, Margherita; Avventuroso, Federica Marzocchi; De Lisio, Sara; Musti, Muriel Assunta; Franceschi, Enrico; Esposti, Roberta Degli; Lombardo, Laura; Cavallo, Giovanna; Di Battista, Monica; Rimondini, Simonetta; Poggi, Rosalba; Susini, Cinzia; Renzi, Rina; Marconi, Linda

2016-01-01

Tong Len meditation is an important therapeutic tool in the Tibetan medicine, and it can be used for self-healing and/or to heal others. Currently, in the West, there is no scientific study concerning the efficacy of a Tong Len distant healing effect on psychological disorders in cancer patients. To evaluate a distant healing effect of Tong Len meditation on stress, anxiety, depression, fatigue, and self-perceived quality of life in cancer patients. These psychological objectives were chosen as a consequence of the limited scientific literature of present day. We performed a double-blind randomized controlled trial on 103 cancer patients with tumors. Overall, 12 meditators used Tong Len in aid of 52 patients randomly selected as experimental group, while the remaining 51 patients constituted the control group. Patients and meditators did not know each other. All patients completed profile of mood states (POMS) and European Quality of Life-5 dimensions (EQ-5D) questionnaires before treatment (T0), after two (T1) and three months of treatment (T2), and one month after treatment cessation (T3). With regard to the parameters related to depression, a statistically significant improvement (P = .003) was observed in the treatment group compared to controls. On the other hand, the vigor/activity parameter saw significant improvements in the control group (P = .009). Both groups exhibited significant improvements in the other factors assessed in the POMS and EQ-5D questionnaires. This study did not provide sufficient evidence supporting an efficacy of Tong Len meditation in distant psychological healing as compared to a control condition. The research highlighted some psychological improvements through Tong Len distant meditation in a group of patients unknown to meditators. Therefore, the enhancement detected in most parameters in both treatment and control groups raises interest on in-depth analysis and evaluation of distant meditation on cancer patients to mitigate

Gram negative bacteria and contact lens induced acute red eye

Directory of Open Access Journals (Sweden)

Sankaridurg Padmaja

1996-01-01

Full Text Available Two patients using hydrogel contact lenses on a daily wear schedule slept overnight with the lenses and woke up with a Contact Lens Induced Acute Red Eye (CLARE. The contact lenses recovered aseptically at the time of the event grew significant colonies of Pseudomonas aeruginosa and Aeromonas hydrophila in patient A and Pseudomonas aeruginosa and Serratia liquefaciens from patient B. Similar organisams from the contact lenses were recovered from the lens case and lens care solutions of patient B. In both the patients the condition resolved on discontinuation of lens wear. Patient compliance as a requirement for successful contact lens wear is highlighted with the illustration of these cases.

Assessing breathing motion by shape matching of lung and diaphragm surfaces

Science.gov (United States)

Urschler, Martin; Bischof, Horst

2005-04-01

Studying complex thorax breating motion is an important research topic for accurate fusion of functional and anatomical data, radiotherapy planning or reduction of breathing motion artifacts. We investigate segmented CT lung, airway and diaphragm surfaces at several different breathing states between Functional Residual and Total Lung Capacity. In general, it is hard to robustly derive corresponding shape features like curvature maxima from lung and diaphragm surfaces since diaphragm and rib cage muscles tend to deform the elastic lung tissue such that e.g. ridges might disappear. A novel registration method based on the shape context approach for shape matching is presented where we extend shape context to 3D surfaces. The shape context approach was reported as a promising method for matching 2D shapes without relying on extracted shape features. We use the point correspondences for a non-rigid thin-plate-spline registration to get deformation fields that describe the movement of lung and diaphragm. Our validation consists of experiments on phantom and real sheep thorax data sets. Phantom experiments make use of shapes that are manipulated with known transformations that simulate breathing behaviour. Real thorax data experiments use a data set showing lungs and diaphragm at 5 distinct breathing states, where we compare subsets of the data sets and qualitatively and quantitatively asses the registration performance by using manually identified corresponding landmarks.

Multiple methods of surgical treatment combined with primary IOL implantation on traumatic lens subluxation/dislocation in patients with secondary glaucoma.

Science.gov (United States)

Wang, Rui; Bi, Chun-Chao; Lei, Chun-Ling; Sun, Wen-Tao; Wang, Shan-Shan; Dong, Xiao-Juan

2014-01-01

To describe clinical findings and complications from cases of traumatic lens subluxation/dislocation in patients with secondary glaucoma, and discuss the multiple treating methods of operation combined with primary intraocular lens (IOL) implantation. Non-comparative retrospective observational case series. 30 cases (30 eyes) of lens subluxation/dislocation in patients with secondary glaucoma were investigated which accepted the surgical treatment by author in the Ophthalmology of Xi'an No.4 Hospital from 2007 to 2011. According to the different situations of lens subluxation/dislocation, various surgical procedures were performed such as crystalline lens phacoemulsification, crystalline lens phacoemulsification combined anterior vitrectomy, intracapsular cataract extraction combined anterior vitrectomy, lensectomy combined anterior vitrectomy though peripheral transparent cornea incision, pars plana lensectomy combined pars plana vitrectomy, and intravitreal cavity crystalline lens phacofragmentation combined pars plana vitrectomy. And whether to implement trabeculectomy depended on the different situations of secondary glaucoma. The posterior chamber intraocular lenses (PC-IOLs) were implanted in the capsular-bag or trassclerally sutured in the sulus decided by whether the capsular were present. visual acuity, intraocular pressure, the situation of intraocular lens and complications after the operations. The follow-up time was 11-36mo (21.4±7.13). Postoperative visual acuity of all eyes were improved; 28 cases maintained IOP below 21 mm Hg; 2 cases had slightly IOL subluxation, 4 cases had slightly tilted lens optical area; 1 case had postoperative choroidal detachment; 4 cases had postoperative corneal edema more than 1wk, but eventually recovered transparent; 2 cases had mild postoperative vitreous hemorrhage, and absorbed 4wk later. There was no postoperative retinal detachment, IOL dislocation, and endophthalmitis. To take early treatment of traumatic lens

Diaphragm flange and method for lowering particle beam impedance at connected beam tubes of a particle accelerator

Energy Technology Data Exchange (ETDEWEB)

Biallas, George Herman

2017-07-04

A diaphragm flange for connecting the tubes in a particle accelerator while minimizing beamline impedance. The diaphragm flange includes an outer flange and a thin diaphragm integral with the outer flange. Bolt holes in the outer flange provide a means for bolting the diaphragm flange to an adjacent flange or beam tube having a mating bolt-hole pattern. The diaphragm flange includes a first surface for connection to the tube of a particle accelerator beamline and a second surface for connection to a CF flange. The second surface includes a recessed surface therein and a knife-edge on the recessed surface. The diaphragm includes a thickness that enables flexing of the integral diaphragm during assembly of beamline components. The knife-edge enables compression of a soft metal gasket to provide a leak-tight seal.

[Iris hooks and modified capsular tension ring for subluxation lens in patients with Marfan's syndrome].

Science.gov (United States)

Wu, Wen-Jie; Zheng, Dan-ying; Zheng, Ying-feng; Cai, Xiao-yu

2007-02-01

To evaluate clinical efficiency and safety of the iris hooks and modified capsular tension ring (MCTR) for the treatment of subluxation lens in patients with Marfan's syndrome. This study comprised 5 patients (7 eyes) with Marfan's syndrome and subluxation lens. After 3.2 mm clear cornea incision and continuous curvilinear capsulorhexis (CCC), 2 - 4 disposable nylon iris hooks were inserted through the stab incisions and placed in the capsulorhexis to support the capsule and enlarged the CCC. Following irrigation/aspiration, a MCTR with suture in its eyelet was placed in the capsule bag. After tightening and tying the suture of MCTR, the capsular bag was centered and fixed. A foldable AcrySof one-piece intraocular lens (IOL) was then placed in the capsule bag. Twelve months after the operation, the best corrected visual acuity was >/= 0.8 in six eyes and 0.7 in one eye. The scheimpflug images obtained from the Pentacam demonstrated that the IOL were well centered. UBM showed that all the MCTR and the haptics of the IOL were in the capsule bag, the eyelet of the MCTR was rested stably between the capsulorhexis margin and the iris. The retroillumination photograph indicated that only one eye had obvious posterior capsular opacification. No intraoperative and postoperative complications such as prolapse of vitreous and retina detachment was occurred. The iris hooks can provide excellent intraoperative capsule-lens stability and facilitate the manipulation during operation. MCTR allows additional suture fixation to the eye wall without damaging the capsular bag and maintains the long-term stability of the intraocular lens. Furthermore, MCTR is helpful for avoiding dislocation of the IOL due to progressive weakening of the zonular fibers in some patients and provides long-term safety.

Clinical study of ultrasound-guided percutaneous radiofrequency ablation for primary hepatic carcinoma adjacent to the diaphragm

Directory of Open Access Journals (Sweden)

LI Meng

2015-04-01

Full Text Available ObjectiveTo investigate the safety and efficacy of ultrasound (US-guided percutaneous radiofrequency ablation (RFA for primary hepatic carcinoma adjacent to the diaphragm. MethodsThis study included 277 patients with 362 lesions of primary hepatic carcinoma managed with US-guided percutaneous RFA in 302 Hospital of PLA from January 2011 to October 2014. Sixty-six patients with 71 hepatocellular carcinomas (HCCs located less than 5 mm from the diaphragm were in study group, and 95 patients with 114 HCCs located more than 10 mm from the hepatic surface were in control group. The patients′ symptoms and complications were observed after the therapy. The complete ablation rate, local tumor progression rate, and complication rate were compared between the two groups. Comparison of continuous data between the two groups was made by independent-samples t test, while comparison of categorical data was made by chi-square test. ResultsAt one month after operation, 65 (91.5% of 71 tumors in the study group and 107 (93.9% of 114 tumors in the control group achieved complete ablation, according to contrast-enhanced CT and MRI, and there was no significant difference between the two groups (χ2=0.36, P=0.55. The postoperative follow-up showed that the local tumor progression rates in the study group and control group were 16.9% and 13.2%, respectively, without significant difference between the two groups (χ2=0.49, P=0.48. In the study group, 22 patients developed adverse reactions, versus 37 patients in the control group (χ2=2.60, P=0.11. ConclusionUS-guided percutaneous RFA is a safe and effective means for the treatment of primary hepatic carcinoma adjacent to the diaphragm.

Right Diaphragm Spontaneous Rupture: A Surgical Approach

Directory of Open Access Journals (Sweden)

Duilio Divisi

2011-01-01

Full Text Available We present a case of spontaneous rupture of the diaphragm, characterized by nonspecific symptoms. The rapid diagnosis and appropriate surgical approach led to a positive resolution of the pathology.

Free radicals in hypoxic rat diaphragm contractility: no role for xanthine oxidase.

NARCIS (Netherlands)

Heunks, L.M.A.; Machiels, H.A.; Abreu, R.A. de; Zhu, X.; Heijden, E. van der; Dekhuijzen, P.N.R.

2001-01-01

Recent evidence indicates that hypoxia enhances the generation of oxidants. Little is known about the role of free radicals in contractility of the rat diaphragm during hypoxia. We hypothesized that antioxidants improve contractility of the hypoxic rat diaphragm and that xanthine oxidase (XO) is an

Effects of cartap on isolated mouse phrenic nerve diaphragm and its related mechanism.

Science.gov (United States)

Liao, J W; Kang, J J; Liu, S H; Jeng, C R; Cheng, Y W; Hu, C M; Tsai, S F; Wang, S C; Pang, V F

2000-06-01

Cartap, a nereistoxin analogue pesticide, is reported to have no irritation to eyes in rabbits. However, we have demonstrated recently that cartap could actually cause acute death in rabbits via ocular exposure. Our preliminary study with isolated mouse phrenic nerve diaphragms has shown that instead of neuromuscular blockade, cartap caused muscular contracture. The objective of the study was to examine the effect of cartap on the neuromuscular junction in more detail and to investigate its possible underlying mechanism with isolated mouse phrenic nerve diaphragms and sarcoplasmic reticulum (SR) vesicles. Cartap or nereistoxin at various concentrations was added in the organ bath with isolated mouse phrenic nerve diaphragm and both nerve- and muscle-evoked twitches were recorded. Instead of blocking the neuromuscular transmission as nereistoxin did, cartap caused contracture in stimulated or quiescent isolated mouse phrenic nerve diaphragm. Both the cartap-induced muscular contracture force and the time interval to initiate the contracture were dose-dependent. The contracture induced by cartap was not affected by the pretreatment of the diaphragm with the acetylcholine receptor blocker alpha-bungarotoxin; the Na(+) channel blocker tetrodotoxin; or various Ca(2+) channel blockers, NiCl(2), verapamil, and nifedipine. On the contrary, the contracture was significantly inhibited when the diaphragm was pretreated with ryanodine or EGTA containing Ca(2+)-free Krebs solution or in combination. This suggested that both internal and extracellular Ca(2+) might participate in cartap-induced skeletal muscle contracture. Moreover, cartap inhibited the [(3)H]-ryanodine binding to the Ca(2+) release channel of SR in a dose-dependent manner. Additionally, cartap could induce a significant reduction in Ca(2+)-ATPase activity of SR vesicles at a relatively high dose. The results suggested that cartap might cause the influx of extracellular Ca(2+) and the release of internal Ca(2

Toric Intraocular Lens Outcomes in Patients With Glaucoma.

Science.gov (United States)

Brown, Reay H; Zhong, Le; Bozeman, Caroline W; Lynch, Mary G

2015-06-01

To report the outcomes of toric intraocular lens implantation in patients with glaucoma and corneal astigmatism. One hundred twenty-six eyes of 87 patients with glaucoma and corneal astigmatism that underwent cataract surgery with an AcrySof toric intraocular lens (Alcon Laboratories, Inc., Fort Worth, TX) implant were selected for this single-center, retrospective case series. Corrected distance visual acuity, intraocular pressure, and refractive astigmatism were measured in each eye preoperatively and postoperatively. Uncorrected distance visual acuity and toric alignment were measured postoperatively. The uncorrected distance visual acuity was 0.04 ± 0.08 logMAR (20/22 Snellen) for all eyes. Ninety-eight percent of all eyes achieved an uncorrected distance visual acuity of 20/40 or better, with 76% achieving 20/25 or better and 47% achieving 20/20. The corrected distance visual acuity for all eyes was 0.01 ± 0.03 logMAR (20/20.5 Snellen) postoperatively. The refractive cylinder improved from 1.47 ± 1.10 diopters preoperatively to 0.31 ± 0.37 diopters postoperatively. The residual refractive cylinder was 1.00 diopter or less in 97% of eyes, 0.75 diopters or less in 90% of eyes, and 0.50 diopters or less in 83% of eyes. Mean misalignment was 4.4° ± 5.1°. Intraocular pressure decreased by a mean of 2.3 ± 3.3 mm Hg following the surgery. Toric intraocular lenses can reliably reduce astigmatism and improve uncorrected vision in eyes with cataract and glaucoma. Copyright 2015, SLACK Incorporated.

Design of calandria-end shield support diaphragm of Narora Atomic Power Project

Energy Technology Data Exchange (ETDEWEB)

Srivastava, S K; Nanda Kumar, S; Kakodkar, A

1975-01-01

The calandria-end shield diaphragm is one of the important components in Narora Atomic Power Plant. The support diaphragm is designed against elastic and plastic instability failures. Method of analysis for elastic and plastic instability is discussed for normal loading, pipe rupture loading, and earthquake loading.

Design of calandria-end shield support diaphragm of Narora Atomic Power Project

International Nuclear Information System (INIS)

Srivastava, S.K.; Nanda Kumar, S.; Kakodkar, A.

1975-01-01

The calandria-end shield diaphragm is one of the important components in Narora Atomic Power Plant. The support diaphragm is designed against elastic and plastic instability failures. Method of analysis for elastic and plastic instability is discussed for normal loading, pipe rupture loading and earthquake loading. (author)

Investigation into the behaviour of concrete anchored diaphragm walls under earthquake condition

International Nuclear Information System (INIS)

Saba, H. R.; Rahaii, A. R.

2003-01-01

Diaphragm walls are frequently used in civil Engineering projects. Considering the variety and important volume of consumed materials (concrete, anchors and soil), one of the important factors for design and construction of these walls, are their behaviour under different executive, and loading conditions. In this paper, various models of concrete diaphragms with different number of anchors and soil parameters under static and dynamic loading have been investigated using finite element method with nonlinear models. Results including the internal forces in diaphragm walls, variation of forces in the anchors, shape of the sliding surface and variation of pressure in soil are obtained and compared. An experimental tool with suitable measurement systems for determining the pressure and internal forces was designed and realised. Also with similitude and dimensional analyses, diaphragms with different number of anchors were built and set on the shaking table test and experimented under different accelograms. Finally results of nonlinear dynamic analysis were compared with experimental results

Proof mass effects on spiral electrode d33 mode piezoelectric diaphragm-based energy harvester

KAUST Repository

Shen, Zhiyuan; Liu, Shuwei; Miao, Jianmin; Woh, Lye Sun; Wang, Zhihong

2013-01-01

This paper presents the characterization of an energy harvester using a piezoelectric diaphragm as the vibration energy conversion microstructure. The diaphragm containing the spiral electrode operates in the d33 mode. The energy harvesting performance of the diaphragm was characterized. The optimal resistance load and the working frequency were characterized. The resonance tuning and the energy harvesting enhancement due to a proof mass were verified. © 2013 IEEE.

A modified SILCS contraceptive diaphragm for long-term controlled release of the HIV microbicide dapivirine.

Science.gov (United States)

Major, Ian; Boyd, Peter; Kilbourne-Brook, Maggie; Saxon, Gene; Cohen, Jessica; Malcolm, R Karl

2013-07-01

There is considerable interest in developing new multipurpose prevention technologies to address women's reproductive health needs. This study describes an innovative barrier contraceptive device--based on the SILCS diaphragm--that also provides long-term controlled release of the lead candidate anti-HIV microbicide dapivirine. Diaphragm devices comprising various dapivirine-loaded polymer spring cores overmolded with a nonmedicated silicone elastomer sheath were fabricated by injection molding processes. In vitro release testing, thermal analysis and mechanical characterization were performed on the devices. A diaphragm device containing a polyoxymethylene spring core loaded with 10% w/w dapivirine provided continuous and controlled release of dapivirine over a 6-month period, with a mean in vitro daily release rate of 174 mcg/day. The mechanical properties of the new diaphragm were closely matched to the SILCS diaphragm. The study demonstrates proof of concept for a dapivirine-releasing diaphragm with daily release quantities potentially capable of preventing HIV transmission. In discontinuous clinical use, release of dapivirine may be readily extended over 1 or more years. Copyright © 2013 Elsevier Inc. All rights reserved.

Successful Reinnervation of the Diaphragm After Intercostal to Phrenic Nerve Neurotization in Patients With High Spinal Cord Injury.

Science.gov (United States)

Nandra, Kulvir S; Harari, Martin; Price, Thea P; Greaney, Patrick J; Weinstein, Michael S

2017-08-01

Our objective in this study was to extend diaphragmatic pacing therapy to include paraplegic patients with high cervical spinal cord injuries between C3 and C5. Diaphragmatic pacing has been used in patients experiencing ventilator-dependent respiratory failure due to spinal cord injury as a means to reduce or eliminate the need for mechanical ventilation. However, this technique relies on intact phrenic nerve function. Recently, phrenic nerve reconstruction with intercostal nerve grafting has expanded the indications for diaphragmatic pacing. Our study aimed to evaluate early outcomes and efficacy of intercostal nerve transfer in diaphragmatic pacing. Four ventilator-dependent patients with high cervical spinal cord injuries were selected for this study. Each patient demonstrated absence of phrenic nerve function via external neck stimulation and laparoscopic diaphragm mapping. Each patient underwent intercostal to phrenic nerve grafting with implantation of a phrenic nerve pacer. The patients were followed, and ventilator dependence was reassessed at 1 year postoperatively. Our primary outcome was measured by the amount of time our patients tolerated off the ventilator per day. We found that all 4 patients have tolerated paced breathing independent of mechanical ventilation, with 1 patient achieving 24 hours of tracheostomy collar. From this study, intercostal to phrenic nerve transfer seems to be a promising approach in reducing or eliminating ventilator support in patients with C3 to C5 high spinal cord injury.

Association Between Carotid Bulb Diaphragm and Ischemic Stroke in Young Afro-Caribbean Patients: A Population-Based Case-Control Study.

Science.gov (United States)

Joux, Julien; Boulanger, Marion; Jeannin, Severine; Chausson, Nicolas; Hennequin, Jean-Luc; Molinié, Vincent; Smadja, Didier; Touzé, Emmanuel; Olindo, Stephane

2016-10-01

Carotid bulb diaphragm (CBD) has been described in young carotid ischemic stroke (CIS) patients, especially in blacks. However, the prevalence of CBD in CIS patients is unknown, and whether CBD is a risk factor for CIS remains unclear. We assessed the association between CBD and incident CIS in a population-based study. We selected all young (young (stroke-free patients admitted for a road crash who routinely had computed tomographic angiography. Odds ratio (ORs) were calculated by conditional logistic regression adjusted for hypertension, dyslipidemia, diabetes and smoking. CIS associated with ipsilateral CBD incidence was 3.8 per 100 000 person-years (95% confidence interval, 1.4-6.1). Prevalence of ipsilateral CBD was 23% in all CIS and 37% in undetermined CIS patients. When restricted to undetermined CIS, CBD prevalence was 24 times higher than that in controls (adjusted OR, 24.1; 95% confidence interval, 1.8-325.6). CBD is associated with an increased risk of ipsilateral CIS in young Afro-Caribbean population. © 2016 American Heart Association, Inc.

Primary intraocular lens implantation for penetrating lens trauma in Africa.

Science.gov (United States)

Bowman, R J; Yorston, D; Wood, M; Gilbert, C; Foster, A

1998-09-01

This study aimed to audit the surgical strategy of primary posterior chamber intraocular lens implantation for cases of recent penetrating trauma involving the lens in an African population. Retrospective, noncomparative case series. Seventy-two cases are reported, including all patients who underwent primary intraocular lens implantation for traumatic cataract extraction performed within 1 month of injury between 1988 and 1996. Demographic characteristics and follow-up attendance rates are analyzed. Surgical technique and the occurrence of intraoperative and postoperative complications are reported. Visual outcomes are reported with detailed analysis for cases of poor visual outcome. Mean age was 14.3 years (standard deviation = 11.1), 57 (79%) were male and 15 (21%) were female (chi-square = 23.66, P capsule had been breached by the trauma in 27 (38%) cases, and 15 of these required anterior vitrectomy. Capsular fixation of the implant was achieved in 49% of patients, the remainder having sulcus fixation. Intraoperative rupture of the posterior capsule occurred in four cases. The only common postoperative complication was acute fibrinous anterior uveitis, which occurred in 29 (40%) patients, and 32% of patients followed up for at least 6 months required secondary posterior capsulotomy. This was more common in younger patients (chi-square = 4.2, P < 0.05). Corrected postoperative visual acuities were available for 51 patients, of which 71% achieved 20/60 or better visual acuity. Patients 6 years of age or younger were less likely to achieve 20/60 (chi-square = 6.61, P = 0.01). This surgical strategy has proved successful, producing good visual results and causing no sight-threatening complications. Primary posterior capsulotomy may be appropriate for younger patients.

Multiple methods of surgical treatment combined with primary IOL implantation on traumatic lens subluxation/dislocation in patients with secondary glaucoma

Directory of Open Access Journals (Sweden)

Rui Wang

2014-04-01

Full Text Available AIM:To describe clinical findings and complications from cases of traumatic lens subluxation/dislocation in patients with secondary glaucoma, and discuss the multiple treating methods of operation combined with primary intraocular lens (IOL implantation.METHODS:Non-comparative retrospective observational case series. Participants:30 cases (30 eyes of lens subluxation/dislocation in patients with secondary glaucoma were investigated which accepted the surgical treatment by author in the Ophthalmology of Xi''an No.4 Hospital from 2007 to 2011. According to the different situations of lens subluxation/dislocation, various surgical procedures were performed such as crystalline lens phacoemulsification, crystalline lens phacoemulsification combined anterior vitrectomy, intracapsular cataract extraction combined anterior vitrectomy, lensectomy combined anterior vitrectomy though peripheral transparent cornea incision, pars plana lensectomy combined pars plana vitrectomy, and intravitreal cavity crystalline lens phacofragmentation combined pars plana vitrectomy. And whether to implement trabeculectomy depended on the different situations of secondary glaucoma. The posterior chamber intraocular lenses (PC-IOLs were implanted in the capsular-bag or trassclerally sutured in the sulus decided by whether the capsular were present. Main outcome measures:visual acuity, intraocular pressure, the situation of intraocular lens and complications after the operations.RESULTS: The follow-up time was 11-36mo (21.4±7.13. Postoperative visual acuity of all eyes were improved; 28 cases maintained IOP below 21 mm Hg; 2 cases had slightly IOL subluxation, 4 cases had slightly tilted lens optical area; 1 case had postoperative choroidal detachment; 4 cases had postoperative corneal edema more than 1wk, but eventually recovered transparent; 2 cases had mild postoperative vitreous hemorrhage, and absorbed 4wk later. There was no postoperative retinal detachment, IOL

Temperature Compensation Fiber Bragg Grating Pressure Sensor Based on Plane Diaphragm

Science.gov (United States)

Liang, Minfu; Fang, Xinqiu; Ning, Yaosheng

2018-03-01

Pressure sensors are the essential equipments in the field of pressure measurement. In this work, we propose a temperature compensation fiber Bragg grating (FBG) pressure sensor based on the plane diaphragm. The plane diaphragm and pressure sensitivity FBG (PS FBG) are used as the pressure sensitive components, and the temperature compensation FBG (TC FBG) is used to improve the temperature cross-sensitivity. Mechanical deformation model and deformation characteristics simulation analysis of the diaphragm are presented. The measurement principle and theoretical analysis of the mathematical relationship between the FBG central wavelength shift and pressure of the sensor are introduced. The sensitivity and measure range can be adjusted by utilizing the different materials and sizes of the diaphragm to accommodate different measure environments. The performance experiments are carried out, and the results indicate that the pressure sensitivity of the sensor is 35.7 pm/MPa in a range from 0 MPa to 50 MPa and has good linearity with a linear fitting correlation coefficient of 99.95%. In addition, the sensor has the advantages of low frequency chirp and high stability, which can be used to measure pressure in mining engineering, civil engineering, or other complex environment.

Temperature Compensation Fiber Bragg Grating Pressure Sensor Based on Plane Diaphragm

Science.gov (United States)

Liang, Minfu; Fang, Xinqiu; Ning, Yaosheng

2018-06-01

Pressure sensors are the essential equipments in the field of pressure measurement. In this work, we propose a temperature compensation fiber Bragg grating (FBG) pressure sensor based on the plane diaphragm. The plane diaphragm and pressure sensitivity FBG (PS FBG) are used as the pressure sensitive components, and the temperature compensation FBG (TC FBG) is used to improve the temperature cross-sensitivity. Mechanical deformation model and deformation characteristics simulation analysis of the diaphragm are presented. The measurement principle and theoretical analysis of the mathematical relationship between the FBG central wavelength shift and pressure of the sensor are introduced. The sensitivity and measure range can be adjusted by utilizing the different materials and sizes of the diaphragm to accommodate different measure environments. The performance experiments are carried out, and the results indicate that the pressure sensitivity of the sensor is 35.7 pm/MPa in a range from 0 MPa to 50 MPa and has good linearity with a linear fitting correlation coefficient of 99.95%. In addition, the sensor has the advantages of low frequency chirp and high stability, which can be used to measure pressure in mining engineering, civil engineering, or other complex environment.

Convergence of pattern generator outputs on a common mechanism of diaphragm motor unit recruitment.

Science.gov (United States)

Mantilla, Carlos B; Seven, Yasin B; Sieck, Gary C

2014-01-01

Motor units are the final element of neuromotor control. In manner analogous to the organization of neuromotor control in other skeletal muscles, diaphragm motor units comprise phrenic motoneurons located in the cervical spinal cord that innervate the diaphragm muscle, the main inspiratory muscle in mammals. Diaphragm motor units play a primary role in sustaining ventilation but are also active in other nonventilatory behaviors, including coughing, sneezing, vomiting, defecation, and parturition. Diaphragm muscle fibers comprise all fiber types. Thus, diaphragm motor units display substantial differences in contractile and fatigue properties, but importantly, properties of the motoneuron and muscle fibers within a motor unit are matched. As in other skeletal muscles, diaphragm motor units are recruited in order such that motor units that display greater fatigue resistance are recruited earlier and more often than more fatigable motor units. The properties of the motor unit population are critical determinants of the function of a skeletal muscle across the range of possible motor tasks. Accordingly, fatigue-resistant motor units are sufficient to generate the forces necessary for ventilatory behaviors, whereas more fatigable units are only activated during expulsive behaviors important for airway clearance. Neuromotor control of diaphragm motor units may reflect selective inputs from distinct pattern generators distributed according to the motor unit properties necessary to accomplish these different motor tasks. In contrast, widely distributed inputs to phrenic motoneurons from various pattern generators (e.g., for breathing, coughing, or vocalization) would dictate recruitment order based on intrinsic electrophysiological properties. © 2014 Elsevier B.V. All rights reserved.

Diffusivity measurements in some organic solvents by a gas-liquid diaphragm cell

NARCIS (Netherlands)

Littel, R.J.; Littel, R.J.; Versteeg, Geert; van Swaaij, Willibrordus Petrus Maria

1992-01-01

A diaphragm cell has been developed for the measurement of diffusion coefficients of gases In liquids. The diaphragm cell is operated batchwise with respect to both gas and liquid phases, and the diffusion process Is followed by means of the gas pressure decrease which is recorded by means of a

Diffusivity Measurements in Some Organic Solvents by a Gas-Liquid Diaphragm Cell

NARCIS (Netherlands)

Littel, Rob J.; Versteeg, Geert F.; Swaaij, Wim P.M. van

1992-01-01

A diaphragm cell has been developed for the measurement of diffusion coefficients of gases in liquids. The diaphragm cell is operated batchwise with respect to both gas and liquid phases, and the diffusion process is followed by means of the gas pressure decrease which is recorded by means of a

Associated depression in pseudophakic patients with intraocular lens with and without chromophore

Directory of Open Access Journals (Sweden)

Mendoza-Mendieta ME

2016-03-01

Full Text Available María Elena Mendoza-Mendieta, Ana Aurora Lorenzo-Mejía Association to Prevent Blindness in Mexico (APEC, Hospital “Dr Luis Sánchez Bulnes”, Mexico City, Mexico Background: With aging, the crystalline lens turns yellowish, which increases the absorption of wavelengths in the blue electromagnetic spectrum, reducing their photoreception in the retina. Since these wavelengths are the main stimulus in the regulation of the circadian rhythm, progressive reduction in their transmission is associated with chronic sleep disturbances and depression in elderly patients. Cataract extraction improves circadian photoreception at any age. However, lenses that block blue waves have 27% to 38% less melatonin suppression than lenses that block only ultraviolet (UV rays. Purpose: To assess the depression symptoms in subjects who have had bilateral phacoemulsification and intraocular lens (IOL implants, one group with yellow chromophore IOLs and the other group with transparent IOLs were compared. Setting: Association to Prevent Blindness in Mexico (APEC, Hospital “Dr Luis Sánchez Bulnes”. Design: This was an observational, cross-sectional, and single-center study. Materials and methods: Twenty-six subjects between 60 and 80 years of age, with a history of bilateral phacoemulsification and placement of the same type of IOL in both eyes from 4 to 12 months prior to the study, who attended the follow-up visits and agreed to participate in this study, and provided signed informed consent were included in the study. They were asked to answer the short version of the 15-item Geriatric Depression Scale. Results: The average age of the study participants was 72.5±5.94 years. The group without chromophore included 46.1% (n=12 of the patients and the group with chromophore included 53.9% (n=14 of the patients (P=0.088. Conclusion: In the group of patients with IOLs that block the passage of blue light, the depression rate was 21.4%, a rate similar to that

Diaphragm Muscle Weakness Following Acute Sustained Hypoxic Stress in the Mouse Is Prevented by Pretreatment with N-Acetyl Cysteine

Directory of Open Access Journals (Sweden)

Andrew J. O’Leary

2018-01-01

Full Text Available Oxygen deficit (hypoxia is a major feature of cardiorespiratory diseases characterized by diaphragm dysfunction, yet the putative role of hypoxic stress as a driver of diaphragm dysfunction is understudied. We explored the cellular and functional consequences of sustained hypoxic stress in a mouse model. Adult male mice were exposed to 8 hours of normoxia, or hypoxia (FiO2 = 0.10 with or without antioxidant pretreatment (N-acetyl cysteine, 200 mg/kg i.p.. Ventilation and metabolism were measured. Diaphragm muscle contractile function, myofibre size and distribution, gene expression, protein signalling cascades, and oxidative stress (TBARS were determined. Hypoxia caused pronounced diaphragm muscle weakness, unrelated to increased respiratory muscle work. Hypoxia increased diaphragm HIF-1α protein content and activated MAPK, mTOR, Akt, and FoxO3a signalling pathways, largely favouring protein synthesis. Hypoxia increased diaphragm lipid peroxidation, indicative of oxidative stress. FoxO3 and MuRF-1 gene expression were increased. Diaphragm 20S proteasome activity and muscle fibre size and distribution were unaffected by acute hypoxia. Pretreatment with N-acetyl cysteine substantially enhanced cell survival signalling, prevented hypoxia-induced diaphragm oxidative stress, and prevented hypoxia-induced diaphragm dysfunction. Hypoxia is a potent driver of diaphragm weakness, causing myofibre dysfunction without attendant atrophy. N-acetyl cysteine protects the hypoxic diaphragm and may have application as a potential adjunctive therapy.

Single lens to lens duplication: The missing link

OpenAIRE

Bhatt, Rupal; Jethani, Jitendra; Saluja, Praveen; Bharti, Vinay

2008-01-01

Congenital anomalies of the lens include a wide range from lens coloboma to primary aphakia and doubling of lens. There have been few case reports of double lens; the etiology suggested is metaplastic changes in the surface ectoderm that leads to formation of two lens vesicles and hence resulting in double lens. We report a case with bilobed lens, which raises the possibility of explaining the etiology of double lens.

Improving the Performance of Two-Stage Gas Guns By Adding a Diaphragm in the Pump Tube

Science.gov (United States)

Bogdanoff, D. W.; Miller, Robert J.

1995-01-01

Herein, we study the technique of improving the gun performance by installing a diaphragm in the pump tube of the gun. A CFD study is carried out for the 0.28 in. gun in the Hypervelocity Free Flight Radiation (HFF RAD) range at the NASA Ames Research Center. The normal, full-length pump tube is studied as well as two pump tubes of reduced length (approximately 75% and approximately 33% of the normal length). Significant improvements in performance are calculated to be gained for the reduced length pump tubes upon the addition of the diaphragm. These improvements are identified as reductions in maximum pressures in the pump tube and at the projectile base of approximately 20%, while maintaining the projectile muzzle velocity or as increases in muzzle velocity of approximately 0.5 km/sec while not increasing the maximum pressures in the gun. Also, it is found that both guns with reduced pump tube length (with diaphragms) could maintain the performance of gun with the full length pump tube without diaphragms, whereas the guns with reduced pump tube lengths without diaphragms could not. A five-shot experimental investigation of the pump tube diaphragm technique is carried out for the gun with a pump tube length of 75% normal. The CFD predictions of increased muzzle velocity are borne out by the experimental data. Modest, but useful muzzle velocity increases (2.5 - 6%) are obtained upon the installation of a diaphragm, compared to a benchmark shot without a diaphragm.

Measurement of thermal expansion coefficient of graphene diaphragm using optical fiber Fabry–Perot interference

International Nuclear Information System (INIS)

Li, Cheng; Liu, Qianwen; Peng, Xiaobin; Fan, Shangchun

2016-01-01

Application of the Fabry–Perot (FP) interference method for determining the coefficient of thermal expansion (CTE) of a graphene diaphragm is investigated in this paper. A miniature extrinsic FP interferometric (EFPI) sensor was fabricated by using an approximate 8-layer graphene diaphragm. The extremely thin diaphragm was transferred onto the endface of a ferrule with an inner diameter of 125 μ m, and van der Waals interactions between the graphene diaphragm and its substrate created a low finesse FP interferometer with a cavity length of 36.13 μ m. Double reference FP cavities using two cleaved optical fibers as reflectors were also constructed to differentially cancel the thermal expansion effects of the trapped gas and adhesive material. A temperature test demonstrated an approximate cavity length change of 166.1 nm °C −1 caused by film thermal expansion in the range of 20–60 °C. Then along with the established thermal deformation model of the suspended circular diaphragm, the calculated CTE ranging from  −9.98  ×  10 −6 K −1 to  −2.09  ×  10 −6 K −1 conformed well to the previously measured results. The proposed method would be applicable in other types of elastic materials as the sensitive diaphragm of an EFPI sensor over a wide temperature range. (paper)

DiapHRaGM: A mnemonic to describe the work of breathing in patients with respiratory failure.

Directory of Open Access Journals (Sweden)

Aiman Tulaimat

Full Text Available The assessment of the work of breathing in the definitions of respiratory failure is vague and variable.Identify a parsimonious set of signs to describe the work of breathing in hypoxemic, acutely ill patients.We examined consecutive medical ICU patients receiving oxygen with a mask, non-invasive ventilation, or T-piece. A physician inspected each patient for 10 seconds, rated the level of respiratory distress, and then examined the patient for vital signs and 17 other physical signs. We used the rating of distress as a surrogate for measuring the work of breathing, constructed three multivariate models to identify the one with the smallest number of signs and largest explained variance, and validated it with bootstrap analysis.We performed 402 observations on 240 patients. Respiratory distress was absent in 78, mild in 157, moderate in 107, and severe in 60. Respiratory rate, hypoxia, heart rate, and frequency of most signs increased as distress increased. Respiratory rate and hypoxia explained 43% of the variance in respiratory distress. Diaphoresis, gasping, and contraction of the sternomastoid explained an additional 28%. Heart rate, blood pressure, alertness, agitation, body posture, nasal flaring, audible breathing, cyanosis, tracheal tug, retractions, paradox, scalene or abdominal muscles contraction did not increase the explained variance in respiratory distress.Most of the variance is respiratory distress can be explained by five signs summarized by the mnemonic DiapHRaGM (diaphoresis, hypoxia, respiratory rate, gasping, accessory muscle. This set of signs may allow for efficient, standardized assessments of the work of breathing of hypoxic patients.

Investigation of local spatial spectra of Bessel light beams

CSIR Research Space (South Africa)

Belyi, VN

2009-08-01

Full Text Available plane of lens and illuminated by plane wave. The superposition of plane waves in such scheme is proposed to be generated by point sources distributed within the circular diaphragm. In a case when diaphragm is placed outside of lens focus [2], Bessel... beam can be described as an image in lens of spherical waves superposition formed by some effective circular source in object plane of lens. In the scheme of BLB obtaining based on axicons, the appearance of superposition of plane waves can be studied...

Vitrectorhexis and lens aspiration with posterior chamber intraocular lens implantation in spherophakia.

Science.gov (United States)

Al-Haddad, Christiane; Khatib, Lama

2012-07-01

We describe a technique that uses the vitrector to perform successful lens aspiration and posterior chamber intraocular lens (IOL) implantation in children with spherophakia and anterior lens subluxation. After an anterior chamber maintainer is placed, the ocutome is introduced through a limbal incision to perform a circular vitrectorhexis to avoid excessive manipulation of the unstable lens followed by gentle cortex aspiration. A foldable IOL is injected into the sulcus (3-piece IOL) or bag (1-piece IOL) if the capsule is sufficiently stable. Through a pars plana incision, the ocutome is then used to perform a posterior capsulotomy to prevent late posterior capsule opacification. In our patient, sulcus IOL placement was more stable than in-the-bag placement. Neither author has a financial or proprietary interest in any material or method mentioned. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

D33 mode piezoelectric diaphragm based acoustic transducer with high sensitivity

KAUST Repository

Shen, Zhiyuan; Lu, Jingyu; Tan, Cheewee; Miao, Jianmin; Wang, Zhihong

2013-01-01

This paper presents the design, fabrication, and characterization of an acoustic transducer using a piezoelectric freestanding bulk diaphragm as the sensing element. The diaphragm bearing the spiral electrode operates in d 33 mode, which allows the in-plane deformation of the diaphragm to be converted to the out-of-plane deformation and generates an acoustic wave in the same direction. A finite element code is developed to reorient the material polarization distribution according to the poling field calculated. The first four resonance modes have been simulated and verified by impedance and velocity spectra. The sensitivity and the sound pressure level of the transducer were characterized. The realized sensitivity of 126.21 μV/Pa at 1 kHz is nearly twenty times of the sensitivity of a sandwich d31 mode transducer. © 2012 Elsevier B.V.

Design-based modeling of magnetically actuated soft diaphragm materials

Science.gov (United States)

Jayaneththi, V. R.; Aw, K. C.; McDaid, A. J.

2018-04-01

Magnetic polymer composites (MPC) have shown promise for emerging biomedical applications such as lab-on-a-chip and implantable drug delivery. These soft material actuators are capable of fast response, large deformation and wireless actuation. Existing MPC modeling approaches are computationally expensive and unsuitable for rapid design prototyping and real-time control applications. This paper proposes a macro-scale 1-DOF model capable of predicting force and displacement of an MPC diaphragm actuator. Model validation confirmed both blocked force and displacement can be accurately predicted in a variety of working conditions i.e. different magnetic field strengths, static/dynamic fields, and gap distances. The contribution of this work includes a comprehensive experimental investigation of a macro-scale diaphragm actuator; the derivation and validation of a new phenomenological model to describe MPC actuation; and insights into the proposed model’s design-based functionality i.e. scalability and generalizability in terms of magnetic filler concentration and diaphragm diameter. Due to the lumped element modeling approach, the proposed model can also be adapted to alternative actuator configurations, and thus presents a useful tool for design, control and simulation of novel MPC applications.

Lens subluxation grading system: predictive value for ectopia lentis surgical outcomes

OpenAIRE

Mauro Waiswol; Niro Kasahara

2009-01-01

Objective: To present a classification system to grade ectopia lentis and to assess its usefulness as a predictor for surgical outcomes. Methods: Fifty-one eyes of 28 patients with either simple (19 patients) or Marfan syndrome-associated ectopia lentis (nine patients) with variable degrees of subluxation were operated on. Lens subluxation intensity was graded according to the lens subluxation grading system (LSGS) from grade 1 (lens on the whole pupillary area) up to grade 4 (lens absent fro...

Experimental device for measuring the dynamic properties of diaphragm motors

Science.gov (United States)

Fojtášek, Kamil; Dvořák, Lukáš; Mejzlík, Jan

The subject of this paper is to design and description of the experimental device for the determination dynamic properties of diaphragm pneumatic motors. These motors are structurally quite different from conventional pneumatic linear cylinders. The working fluid is typically compressed air, the piston of motor is replaced by an elastic part and during the working cycle there is a contact of two elastic environments. In the manufacturers catalogs of these motors are not given any working characteristics. Description of the dynamic behavior of diaphragm motor will be used for verification of mathematical models.

Fabry-Perot Diaphragm Fiber Optic Sensor (DFOS for Acoustic Detection

Directory of Open Access Journals (Sweden)

Yan SUN

2007-10-01

Full Text Available A diaphragm fiber optic sensor (DFOS solely based on Fabry-Perot multiple beam interference has been designed and fabricated with micro-electric mechanical system (MEMS technology. The silicon diaphragm with an embossed center was designed with an interference gap width kept accurately. The DFOS was verified to be a truly and purely Fabry-Perot device via a critical test. Parallel testing with a Piezoelectric (PZT sensor showed that the DFOS had high sensitivity. The Fabry-Perot DFOS also demonstrated excellent performance in on-line monitoring of Partial Discharge (PD in power transformers.

Large Epiphrenic Diverticulum with Perforation and Leakage below the Diaphragm

DEFF Research Database (Denmark)

Brønserud, Majken Munk; Brenøe, Anne-Sofie; Eckardt, Jens

2015-01-01

contrast revealed contrast leakage near the minor curvature of the stomach. The following esophagogastroduodenoscopy demonstrated a giant dilatation of the esophagus, as well as a second esophageal lumen originating 25 cm from the incisors. The “false” lumen of the esophagus was located parallel...... to esophagus, ending blindly in a perforation below the diaphragm. The clinical presentation and the patient’s age make it most likely, that it was a long epiphrenic diverticulum of pulsion type. The patient was treated conservatively, discharged after 10 days and has been followed in our outpatient clinic...... for 8 months, until he died of aggressive pulmonary cancer....

DNA damage in lens epithelium of cataract patients in vivo and ex vivo.

Science.gov (United States)

Øsnes-Ringen, Oyvind; Azqueta, Amaia O; Moe, Morten C; Zetterström, Charlotta; Røger, Magnus; Nicolaissen, Bjørn; Collins, Andrew R

2013-11-01

DNA damage has been described in the human cataractous lens epithelium, and oxidative stress generated by UV radiation and endogenous metabolic processes has been suggested to play a significant role in the pathogenesis of cataract. In this study, the aim was to explore the quality and relative quantity of DNA damage in lens epithelium of cataract patients in vivo and after incubation in a cell culture system. Capsulotomy specimens were analysed, before and after 1 week of ex vivo cultivation, using the comet assay to measure DNA strand breaks, oxidized purine and pyrimidine bases and UV-induced cyclobutane pyrimidine dimers. DNA strand breaks were barely detectable, oxidized pyrimidines and pyrimidine dimers were present at low levels, whereas there was a relatively high level of oxidized purines, which further increased after cultivation. The observed levels of oxidized purines in cataractous lens epithelium may support a theory consistent with light damage and oxidative stress as mediators of molecular damage to the human lens epithelium. Damage commonly associated with UV-B irradiation was relatively low. The levels of oxidized purines increased further in a commonly used culture system. This is of interest considering the importance and versatility of ex vivo systems in studies exploring the pathogenesis of cataract. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

One stage resection of spontaneous rupture of hepatocellular carcinoma in the triangular ligament with diaphragm invasion: case report and review of the literature

Directory of Open Access Journals (Sweden)

Park Kwang-Kuk

2012-09-01

Full Text Available Abstract A spontaneous rupture of hepatocellular carcinoma (HCC can lead to extensive hemorrhage and is a rare but life-threatening event. A 58-year-old male patient with no history of trauma presented at our institution with severe epigastric pain and abdominal distension for 6 h. His blood pressure was a 60/40 mmHg, and pulse rate was 132/min. Abdominal contrast enhanced computed tomography (CT imaging revealed a ruptured mass under the left diaphragm and fluid collection in the upper abdomen, flanks and pelvic cavity. Exploratory laparotomy confirmed the presence of an active bleeding tumor in the triangular ligament invading into the diaphragm. The tumor was resected with an appropriate diaphragm margin. The resected tumor was 5 cm in diameter and pathologically identified as hepatocellular carcinoma with a negative surgical margin. This case report shows that ruptured hepatocellular carcinoma should be considered in the differential diagnosis of non-traumatic hemoperitoneum. And it is necessary to set a surgical plan for unpredictable HCC rupture with direct diaphragm invasion.

Distinct functions of Crumbs regulating slit diaphragms and endocytosis in Drosophila nephrocytes.

Science.gov (United States)

Hochapfel, Florian; Denk, Lucia; Mendl, Gudrun; Schulze, Ulf; Maaßen, Christine; Zaytseva, Yulia; Pavenstädt, Hermann; Weide, Thomas; Rachel, Reinhard; Witzgall, Ralph; Krahn, Michael P

2017-12-01

Mammalian podocytes, the key determinants of the kidney's filtration barrier, differentiate from columnar epithelial cells and several key determinants of apical-basal polarity in the conventional epithelia have been shown to regulate podocyte morphogenesis and function. However, little is known about the role of Crumbs, a conserved polarity regulator in many epithelia, for slit-diaphragm formation and podocyte function. In this study, we used Drosophila nephrocytes as model system for mammalian podocytes and identified a conserved function of Crumbs proteins for cellular morphogenesis, nephrocyte diaphragm assembly/maintenance, and endocytosis. Nephrocyte-specific knock-down of Crumbs results in disturbed nephrocyte diaphragm assembly/maintenance and decreased endocytosis, which can be rescued by Drosophila Crumbs as well as human Crumbs2 and Crumbs3, which were both expressed in human podocytes. In contrast to the extracellular domain, which facilitates nephrocyte diaphragm assembly/maintenance, the intracellular FERM-interaction motif of Crumbs is essential for regulating endocytosis. Moreover, Moesin, which binds to the FERM-binding domain of Crumbs, is essential for efficient endocytosis. Thus, we describe here a new mechanism of nephrocyte development and function, which is likely to be conserved in mammalian podocytes.

Aberration design of zoom lens systems using thick lens modules.

Science.gov (United States)

Zhang, Jinkai; Chen, Xiaobo; Xi, Juntong; Wu, Zhuoqi

2014-12-20

A systematic approach for the aberration design of a zoom lens system using a thick lens module is presented. Each component is treated as a thick lens module at the beginning of the design. A thick lens module refers to a thick lens component with a real lens structure, like lens materials, lens curvatures, lens thicknesses, and lens interval distances. All nine third-order aberrations of a thick lens component are considered during the design. The relationship of component aberrations in different zoom positions can be approximated from the aberration shift. After minimizing the aberrations of the zoom lens system, the nine third-order aberrations of every lens component can be determined. Then the thick lens structure of every lens component can be determined after optimization according to their first-order properties and third-order aberration targets. After a third optimization for minimum practical third-order aberrations of a zoom lens system, the aberration design using the thick lens module is complete, which provides a practical zoom lens system with thick lens structures. A double-sided telecentric zoom lens system is designed using the thick lens module in this paper, which shows that this method is practical for zoom lens design.

Percutaneous Radiofrequency Ablation for the Hepatocellular Carcinoma Abutting the Diaphragm: Assessment of Safety and Therapeutic Efficacy

International Nuclear Information System (INIS)

Kang, Tae Wook; Rhim, Hyun Chul; Kim, Eun Young; Kim, Young Sun; Choi, Dong Il; Lee, Won Jae; Lim, Hyo K.

2009-01-01

To assess the safety and therapeutic efficacy of a percutaneous radiofrequency (RF) ablation for the hepatocellular carcinoma (HCC) abutting the diaphragm. We retrospectively assessed 80 patients who underwent a percutaneous RF ablation for a single nodular (< 4 cm) HCC over the last four years. Each patient underwent an ultrasound-guided RF ablation using internally cooled electrodes for the first-line treatment. We divided patients into two subgroups based on whether the index tumor was abutting (less than 5 mm) the diaphragm or not: group A (abutting; n = 31) versus group B (non-abutting; n = 49). We compared the two subgroups for complications and therapeutic efficacy using image and the review of medical records. The statistical assessment included an independent t-test, Fisher's exact test, and chi-square test. The assessment of the diaphragmatic swelling at CT immediately following the procedure was more severe in group A than group B (mean thickness change:1.44 vs. 0.46 mm, p = 0.00). Further, right shoulder pain was more common in group A than B (p = 0.01). Although minor complications (hemothorax 1 case, pleural effusion 1 case) were noted only in group A, no major thoracic complication occurred in either group. The technical success rate was lower in group A than group B (84% vs. 98%, p = 0.03). As well, the primary and secondary technique effectiveness rates in group A and group B were 90% versus 98% (p = 0.29) and 79% versus 91% (p = 0.25), respectively. The local tumor progression rate was higher in group A than in group B (29% vs. 6%, p = 0.02). We found that the percutaneous RF ablation for the HCC abutting the diaphragm is a safe procedure without major complications. However, it is less effective with regard to technical success and local tumor control

Depletion of Pax7+ satellite cells does not affect diaphragm adaptations to running in young or aged mice.

Science.gov (United States)

Murach, Kevin A; Confides, Amy L; Ho, Angel; Jackson, Janna R; Ghazala, Lina S; Peterson, Charlotte A; Dupont-Versteegden, Esther E

2017-10-01

Satellite cell depletion does not affect diaphragm adaptations to voluntary wheel running in young or aged mice. Satellite cell depletion early in life (4 months of age) has minimal effect on diaphragm phenotype by old age (24 months). Prolonged satellite cell depletion in the diaphragm does not result in excessive extracellular matrix accumulation, in contrast to what has been reported in hind limb muscles. Up-regulation of Pax3 mRNA+ cells after satellite cell depletion in young and aged mice suggests that Pax3+ cells may compensate for a loss of Pax7+ satellite cells in the diaphragm. Future investigations should focus on the role of Pax3+ cells in the diaphragm during adaptation to exercise and ageing. Satellite cell contribution to unstressed diaphragm is higher compared to hind limb muscles, which is probably attributable to constant activation of this muscle to drive ventilation. Whether satellite cell depletion negatively impacts diaphragm quantitative and qualitative characteristics under stressed conditions in young and aged mice is unknown. We therefore challenged the diaphragm with prolonged running activity in the presence and absence of Pax7+ satellite cells in young and aged mice using an inducible Pax7 CreER -R26R DTA model. Mice were vehicle (Veh, satellite cell-replete) or tamoxifen (Tam, satellite cell-depleted) treated at 4 months of age and were then allowed to run voluntarily at 6 months (young) and 22 months (aged). Age-matched, cage-dwelling, Veh- and Tam-treated mice without wheel access served as activity controls. Diaphragm muscles were analysed from young (8 months) and aged (24 months) mice. Satellite cell depletion did not alter diaphragm mean fibre cross-sectional area, fibre type distribution or extracellular matrix content in young or aged mice, regardless of running activity. Resting in vivo diaphragm function was also unaffected by satellite cell depletion. Myonuclear density was maintained in young satellite cell

Action of the isolated canine diaphragm on the lower ribs at high lung volumes.

Science.gov (United States)

De Troyer, André; Wilson, Theodore A

2014-10-15

The normal diaphragm has an inspiratory action on the lower ribs, but subjects with chronic obstructive pulmonary disease commonly have an inward displacement of the lateral portions of the lower rib cage during inspiration. This paradoxical displacement, conventionally called 'Hoover's sign', has traditionally been attributed to the direct action of radially oriented diaphragmatic muscle fibres. In the present study, the inspiratory intercostal muscles in all interspaces in anaesthetized dogs were severed so that the diaphragm was the only muscle active during inspiration. The displacements of the lower ribs along the craniocaudal and laterolateral axes and the changes in pleural pressure (∆Ppl) and transdiaphragmatic pressure were measured during occluded breaths and mechanical ventilation at different lung volumes between functional residual capacity (FRC) and total lung capacity. From these data, the separate effects on rib displacement of ∆Ppl and of the force exerted by the diaphragm on the ribs were determined. Isolated spontaneous diaphragm contraction at FRC displaced the lower ribs cranially and outward, but this motion was progressively reversed into a caudal and inward motion as lung volume increased. However, although the force exerted by the diaphragm on the ribs decreased with increasing volume, it continued to displace the ribs cranially and outward. These observations suggest that Hoover's sign is usually caused by the decrease in the zone of apposition and, thus, by the dominant effect of ∆Ppl on the lower ribs, rather than an inward pull from the diaphragm. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.

Effects of acute respiratory and metabolic acidosis on diaphragm muscle obtained from rats.

Science.gov (United States)

Michelet, Pierre; Carreira, Serge; Demoule, Alexandre; Amour, Julien; Langeron, Olivier; Riou, Bruno; Coirault, Catherine

2015-04-01

Acute respiratory acidosis is associated with alterations in diaphragm performance. The authors compared the effects of respiratory acidosis and metabolic acidosis in the rat diaphragm in vitro. Diaphragmatic strips were stimulated in vitro, and mechanical and energetic variables were measured, cross-bridge kinetics calculated, and the effects of fatigue evaluated. An extracellular pH of 7.00 was obtained by increasing carbon dioxide tension (from 25 to 104 mmHg) in the respiratory acidosis group (n = 12) or lowering bicarbonate concentration (from 24.5 to 5.5 mM) in the metabolic acidosis group (n = 12) and the results compared with a control group (n = 12, pH = 7.40) after 20-min exposure. Respiratory acidosis induced a significant decrease in maximum shortening velocity (-33%, P Respiratory acidosis impaired more relaxation than contraction, as shown by impairment in contraction-relaxation coupling under isotonic (-26%, P acidosis group. In rat diaphragm, acute (20 min) respiratory acidosis induced a marked decrease in the diaphragm contractility, which was not observed in metabolic acidosis.

MO-F-CAMPUS-I-04: Patient Eye-Lens Dose Reduction in Routine Brain CT Examinations Using Organ-Based Tube Current Modulation and In-Plane Bismuth Shielding

International Nuclear Information System (INIS)

Tsai, Hui-Yu; Liao, Ying-Lan; Lai, Nan-Ku; Chen, Tou-Rong; Chen, Jun-Rong

2015-01-01

Purpose: The purpose of this study is to assess eye-lens dose for patients who underwent brain CT examinations using two dose reduction Methods: organ-based tube current modulation (OBTCM) and in-plane bismuth shielding method. Methods: This study received institutional review board approval; written informed consent to participate was obtained from all patients. Ninety patients who underwent the routine brain CT examination were randomly assigned to three groups, ie. routine, OBTCM, and bismuth shield. The OBTCM technique reduced the tube current when the X-ray tube rotates in front of patients’ eye-lens region. The patients in the bismuth shield group were covered one-ply bismuth shield in the eyes’ region. Eye-lens doses were measured using TLD-100H chips and the total effective doses were calculated using CT-Expo according to the CT scanning parameters. The surface doses for patients at off-center positions were assessed to evaluate the off-centering effect. Results: Phantom measurements indicates that OBTCM technique could reduced by 26% to 28% of the surface dose to the eye lens, and increased by 25% of the surface dose at the opposed incident direction at the angle of 180°. Patients’ eye-lens doses were reduced 16.9% and 30.5% dose of bismuth shield scan and OBTCM scan, respectively compared to the routine scan. The eye-lens doses were apparently increased when the table position was lower than isocenter. Conclusion: Reducing the dose to the radiosensitive organs, such as eye lens, during routine brain CT examinations could lower the radiation risks. The OBTCM technique and in-plane bismuth shielding could be used to reduce the eye-lens dose. The eye-lens dose could be effectively reduced using OBTCM scan without interfering the diagnostic image quality. Patient position relative the CT gantry also affects the dose level of the eye lens. This study was supported by the grants from the Ministry of Science and Technology of Taiwan (MOST103-2314-B-182

Evaluating the effect of pressure on the diaphragm micro- electro-mechanical thickness and the amount of shift in medical applications

Directory of Open Access Journals (Sweden)

Nazli Zargarpour

2017-04-01

Full Text Available In this paper, the influence of design parameters on the sensitive microphone diaphragm for use in implantable medical applications is presented. The different parameters such as diaphragm shape, size, thickness and different applied pressures on the diaphragm has been considered. The effect of changes in these parameters on the displacement and stress in a variety of shapes of diaphragm is discussed. In order to design the optimal shape of the proposed diaphragm for the considered parameters, it has been simulated and analyzed in software COMSOL. According to the parameters, the diaphragm shapes of square, rectangular and oval with respect to the intended user, average central displacement in human hearing frequency range 20Hz-20KHz are nm 5. 5, nm2. 6, and nm 130 respectively . According to the results of the simulations, the oval-shaped diaphragm that has been studies in this paper, the possibility of implanted medical applications, performance is optimal than other shapes. In addition, the piezoelectric material is PZT which used in the design of the diaphragm.

Repertoire of free-living protozoa in contact lens solutions.

Science.gov (United States)

Bouchoucha, Ibtissem; Aziz, Aurore; Hoffart, Louis; Drancourt, Michel

2016-10-29

The repertoire of free-living protozoa in contact lens solutions is poorly known despite the fact that such protozoa may act as direct pathogens and may harbor intra-cellular pathogens. Between 2009 and 2014, the contact lens solutions collected from patients presenting at our Ophthalmology Department for clinically suspected keratitis, were cultured on non-nutrient agar examined by microscope for the presence of free-living protozoa. All protozoa were identified by 18S rRNA gene sequencing. A total of 20 of 233 (8.6 %) contact lens solution specimens collected from 16 patients were cultured. Acanthamoeba amoeba in 16 solutions (80 %) collected from 12 patients and Colpoda steini, Cercozoa sp., Protostelium sp. and a eukaryotic more closely related to Vermamoeba sp., were each isolated in one solution. Cercozoa sp., Colpoda sp., Protostelium sp. and Vermamoeba sp. are reported for the first time as contaminating contact lens solutions. The repertoire of protozoa in contact lens solutions is larger than previously known.

The influence of tensile forces on the deflection of circular diaphragms in pressure sensors

NARCIS (Netherlands)

Voorthuyzen, J.A.; Bergveld, Piet

1984-01-01

It is known that the deflection of a diaphragm is determined by two mechanisms, bending moments or bending stress and tensile forces or membrane stress. Usually the influence of tensile forces is not taken into account when calculating the mechanical properties of thin diaphragms. Hence the

Documentation of diaphragmal paralysis with digital subtraction techniques

International Nuclear Information System (INIS)

Waggershauser, T.; Muenchen Univ.; Buente, E.; Muenchen Univ.; Kohz, P.; Muenchen Univ.; Fink, U.; Muenchen Univ.

1992-01-01

The causative factors for a paresis of the diaphragm are primarily subsequent to operations on lesions of the phrenic nerve or on such mediastinal tumors as lyphomas which result in compression or infiltration of the nerves. (orig.) [de

CFD Fuel Slosh Modeling of Fluid-Structure Interaction in Spacecraft Propellant Tanks with Diaphragms

Science.gov (United States)

Sances, Dillon J.; Gangadharan, Sathya N.; Sudermann, James E.; Marsell, Brandon

2010-01-01

Liquid sloshing within spacecraft propellant tanks causes rapid energy dissipation at resonant modes, which can result in attitude destabilization of the vehicle. Identifying resonant slosh modes currently requires experimental testing and mechanical pendulum analogs to characterize the slosh dynamics. Computational Fluid Dynamics (CFD) techniques have recently been validated as an effective tool for simulating fuel slosh within free-surface propellant tanks. Propellant tanks often incorporate an internal flexible diaphragm to separate ullage and propellant which increases modeling complexity. A coupled fluid-structure CFD model is required to capture the damping effects of a flexible diaphragm on the propellant. ANSYS multidisciplinary engineering software employs a coupled solver for analyzing two-way Fluid Structure Interaction (FSI) cases such as the diaphragm propellant tank system. Slosh models generated by ANSYS software are validated by experimental lateral slosh test results. Accurate data correlation would produce an innovative technique for modeling fuel slosh within diaphragm tanks and provide an accurate and efficient tool for identifying resonant modes and the slosh dynamic response.

Combined transarterial chemoembolization of the right inferior phrenic artery and radiofrequency ablation for small hepatocellular carcinoma near the diaphragm: its efficacy and safety.

Science.gov (United States)

Hyun, Dongho; Cho, Sung Ki; Shin, Sung Wook; Park, Kwang Bo; Lee, Sang Yub; Park, Hong Suk; Choo, Sung Wook; Do, Young Soo

2018-02-28

The purpose of the study is to report the efficacy and safety of combined transarterial chemoembolization (TACE) of the right inferior phrenic artery (IPA) and radiofrequency ablation (RFA) for small hepatocellular carcinoma (HCC) near the diaphragm supplied by the right IPA. From July 2009 through April 2015, 11 patients with small (≤ 3 cm) HCC near the diaphragm, which was infeasible for ultrasound-guided RFA and supplied by the right IPA, received TACE of the right IPA and subsequent RFA in one session. The safety and therapeutic efficacy, including technique effectiveness and local tumor progression (LTP), were evaluated. Technique effectiveness was achieved in all the 11 patients (100%). During average follow-up period of 39.2 months (range 13-89 months), LTP occurred in none of the 11 patients. There were twelve minor complications in eight patients, including right shoulder pain (n = 4), right pleural effusion (n = 2), diaphragmatic thickening (n = 2), transient lung change (n = 2), subsegmental intrahepatic bile duct stricture (n = 1), and subsegmental hepatic infarction (n = 1). No major complications were encountered CONCLUSION: Combined TACE of the right IPA and RFA can be a safe and effective treatment for small HCC near the diaphragm that is supplied by the right IPA.

Early development of the human pelvic diaphragm

NARCIS (Netherlands)

Koch, Wijnandus Franciscus Robertus Maria

2006-01-01

The last decade an increasing interest in the pelvic floor can be observed in medical sciences. The lack of data on the development of the human pelvic floor is striking. The early development of the human pelvic diaphragm was studied. Materials and methodsUse was made of 38 human embryos and

Displacement and resonance behaviors of a piezoelectric diaphragm driven by a double-sided spiral electrode

KAUST Repository

Shen, Zhiyuan

2012-04-03

This paper presents the design of a lead zirconate titanate (PZT) diaphragm actuated by double-sided patterned electrodes. Au/Cr electrodes were deposited on bulk PZT wafers by sputtering while patterned by a lift-off process. SU-8 thick film was used to form the structural layer. Double-spiral electrode induced in-plane poling and piezoelectric elongation are converted to an out-of-plane displacement due to the confined boundary condition. The influence of different drive configurations and electrode parameters on deflection has been calculated by finite element methods (FEM) using a uniform field model. Impedance and quasi-static displacement spectra of the diaphragm were measured after poling. Adouble-sided patterned electrode diaphragm can be actuated by more drive configurations than a single-sided one. Compared with a single-sided electrode drive, a double-sided out-of-phase drive configuration increases the coupling coefficient of the fundamental resonance from 7.6% to 11.8%. The displacement response of the diaphragm increases from 2.6 to 8.6nmV 1. Configurations including the electric field component perpendicular to the poling direction can stimulate shear modes of the diaphragm. © 2012 IOP Publishing Ltd.

Lens dislocation has a possible relationship with laser iridotomy

Directory of Open Access Journals (Sweden)

Mutoh T

2012-12-01

Full Text Available Tetsuya Mutoh,1,2 Kevin F Barrette,2 Yukihiro Matsumoto,1 Makoto Chikuda11Department of Ophthalmology, Dokkyo Medical University Koshigaya Hospital, Koshigaya City, Saitama, Japan; 2Department of Ophthalmology, Boston University School of Medicine, Boston, MA, USAAbstract: We report our recent experience of four eyes with spontaneous lens dislocation in four patients with no history of trauma or any systemic disease associated with zonular dialysis. Lens dislocation developed with 0.5 to 6 months following laser iridotomy. All patients were male and two eyes were complicated with acute primary angle closure glaucoma preoperatively. Case 1 showed bilateral lens dislocation, while cases 2 and 3 involved unilateral lens dislocation. Cases 2 and 3 showed lenses completely dislocated into the vitreous cavity. All cases needed lens removal and scleral fixation of intraocular lenses. Final visual acuity was 1.2 in all cases. We suspect that laser iridotomy may induce localized zonular dialysis that results in progressive zonular weakness, leading to lens dislocation.Keywords: lens dislocation, laser iridotomy, primary angle closure glaucoma

A new straight accelerator tube with U diaphragm

International Nuclear Information System (INIS)

Liu Jinhong; Lai Weiquan; Deng Yushen; Zhang Jidong

1994-01-01

After calculating the potential distribution and the particle trajectories in electrostatic accelerator tubes, a new straight tube with U diaphragm to suppress secondary particles is proposed. It's properties are demonstrated by the high voltage tests and the γ-rays measurements in the accelerator

Intracapsular lens extraction for the treatment of pupillary block glaucoma associated with anterior subluxation of the crystalline lens.

Science.gov (United States)

Kim, Yong Joon; Ha, Seung Joo

2013-01-01

To report a case of pupillary block glaucoma associated with spontaneous crystalline lens subluxation into the anterior chamber in a 34-year-old man. Dry vitrectomy was performed for securing enough retrolental space, and an intracapsular lens extraction was then performed via a corneolimbal incision. Additional endothelial cell damage was avoided with an injection of viscoelastics and gentle extraction of the crystalline lens. After deepening of the anterior chamber, scleral fixation of the intraocular lens was performed with an ab externo technique. Two months after the operation, a well-fixated intraocular lens was observed and intraocular pressure was stable. The postoperative corneal astigmatism was -3.5 dpt, and the patient had a best-corrected visual acuity of 20/25. Postoperative complications included decreased endothelial cell count and sector iris paralysis near the incision site. An anteriorly subluxated crystalline lens can cause pupillary block glaucoma in healthy young adults. To prevent intraoperative complications, intracapsular lens extraction with dry vitrectomy can be a good surgical option. The endothelial cell density should be closely monitored after surgery.

Process engineering and economic evaluations of diaphragm and membrane chlorine cell technologies. Final report

Energy Technology Data Exchange (ETDEWEB)

1980-12-01

The chlor-alkali manufacturing technologies of (1), diaphragm cells (2), current technology membrane cells (3), catalytic cathode membrane cells (4), oxygen-cathode membrane cells and to a lesser extent several other related emerging processes are studied. Comparisons have been made on the two bases of (1) conventional industrial economics, and (2) energy consumption. The current diaphragm cell may have a small economic advantage over the other technologies at the plant size of 544 metric T/D (600 T/D). The three membrane cells all consume less energy, with the oxygen-cathode cell being the lowest. The oxygen-cathode cell appears promising as a low energy chlor-alkali cell where there is no chemical market for hydrogen. Federal funding of the oxygen-cathode cell has been beneficial to the development of the technology, to electrochemical cell research, and may help maintain the US's position in the international chlor-alkali technology marketplace. Tax law changes inducing the installation of additional cells in existing plants would produce the quickest reduction in power consumption by the chlor-alkali industry. Alternative technologies such as the solid polymer electrolyte cell, the coupling of diaphragm cells with fuel cells and the dynamic gel diaphragm have a strong potential for reducing chloralkali industry power consumption. Adding up all the recent and expected improvements that have become cost-effective, the electrical energy required to produce a unit of chlorine by 1990 should be only 50% to 60% of that used in 1970. In the United States the majority of the market does not demand salt-free caustic. About 75% of the electrolytic caustic is produced in diaphragm cells and only a small part of that is purified. This study indicates that unless membrane cell costs are greatly reduced or a stronger demand develops for salt-free caustic, the diaphragm cells will remain competitive. (WHK)

The role of Sema3–Npn-1 signaling during diaphragm innervation and muscle development

Science.gov (United States)

Huettl, Rosa-Eva; Hanuschick, Philipp; Amend, Anna-Lena; Alberton, Paolo; Aszodi, Attila; Huber, Andrea B.

2016-01-01

ABSTRACT Correct innervation of the main respiratory muscle in mammals, namely the thoracic diaphragm, is a crucial pre-requisite for the functionality of this muscle and the viability of the entire organism. Systemic impairment of Sema3A–Npn-1 (Npn-1 is also known as NRP1) signaling causes excessive branching of phrenic nerves in the diaphragm and into the central tendon region, where the majority of misguided axons innervate ectopic musculature. To elucidate whether these ectopic muscles are a result of misguidance of myoblast precursors due to the loss of Sema3A–Npn-1 signaling, we conditionally ablated Npn-1 in somatic motor neurons, which led to a similar phenotype of phrenic nerve defasciculation and, intriguingly, also formation of innervated ectopic muscles. We therefore hypothesize that ectopic myocyte fusion is caused by additional factors released by misprojecting growth cones. Slit2 and its Robo receptors are expressed by phrenic motor axons and migrating myoblasts, respectively, during innervation of the diaphragm. In vitro analyses revealed a chemoattractant effect of Slit2 on primary diaphragm myoblasts. Thus, we postulate that factors released by motor neuron growth cones have an influence on the migration properties of myoblasts during establishment of the diaphragm. PMID:27466379

Lens stem cells may reside outside the lens capsule: an hypothesis

Directory of Open Access Journals (Sweden)

Meyer Rita A

2007-06-01

Full Text Available Abstract In this paper, we consider the ocular lens in the context of contemporary developments in biological ideas. We attempt to reconcile lens biology with stem cell concepts and a dearth of lens tumors. Historically, the lens has been viewed as a closed system, in which cells at the periphery of the lens epithelium differentiate into fiber cells. Theoretical considerations led us to question whether the intracapsular lens is indeed self-contained. Since stem cells generate tumors and the lens does not naturally develop tumors, we reasoned that lens stem cells may not be present within the capsule. We hypothesize that lens stem cells reside outside the lens capsule, in the nearby ciliary body. Our ideas challenge the existing lens biology paradigm. We begin our discussion with lens background information, in order to describe our lens stem cell hypothesis in the context of published data. Then we present the ciliary body as a possible source for lens stem cells, and conclude by comparing the ocular lens with the corneal epithelium.

Contact lens rehabilitation following repaired corneal perforations

Science.gov (United States)

Titiyal, Jeewan S; Sinha, Rajesh; Sharma, Namrata; Sreenivas, V; Vajpayee, Rasik B

2006-01-01

Background Visual outcome following repair of post-traumatic corneal perforation may not be optimal due to presence of irregular keratometric astigmatism. We performed a study to evaluate and compare rigid gas permeable contact lens and spectacles in visual rehabilitation following perforating corneal injuries. Method Eyes that had undergone repair for corneal perforating injuries with or without lens aspiration were fitted rigid gas permeable contact lenses. The fitting pattern and the improvement in visual acuity by contact lens over spectacle correction were noted. Results Forty eyes of 40 patients that had undergone surgical repair of posttraumatic corneal perforations were fitted rigid gas permeable contact lenses for visual rehabilitation. Twenty-four eyes (60%) required aphakic contact lenses. The best corrected visual acuity (BCVA) of ≥ 6/18 in the snellen's acuity chart was seen in 10 (25%) eyes with spectacle correction and 37 (92.5%) eyes with the use of contact lens (p < 0.001). The best-corrected visual acuity with spectacles was 0.20 ± 0.13 while the same with contact lens was 0.58 ± 0.26. All the patients showed an improvement of ≥ 2 lines over spectacles in the snellen's acuity chart with contact lens. Conclusion Rigid gas permeable contact lenses are better means of rehabilitation in eyes that have an irregular cornea due to scars caused by perforating corneal injuries. PMID:16536877

Miniature all-silica optical fiber pressure sensor with an ultrathin uniform diaphragm.

Science.gov (United States)

Wang, Wenhui; Wu, Nan; Tian, Ye; Niezrecki, Christopher; Wang, Xingwei

2010-04-26

This paper presents an all-silica miniature optical fiber pressure/acoustic sensor based on the Fabry-Perot (FP) interferometric principle. The endface of the etched optical fiber tip and silica thin diaphragm on it form the FP structure. The uniform and thin silica diaphragm was fabricated by etching away the silicon substrate from a commercial silicon wafer that has a thermal oxide layer. The thin film was directly thermally bonded to the endface of the optical fiber thus creating the Fabry-Perot cavity. Thin films with a thickness from 1microm to 3microm have been bonded successfully. The sensor shows good linearity and hysteresis during measurement. A sensor with 0.75 microm-thick diaphragm thinned by post silica etching was demonstrated to have a sensitivity of 11 nm/kPa. The new sensor has great potential to be used as a non-intrusive pressure sensor in a variety of sensing applications.

Automated Diaphragm Loading for the LB/TS (Large Blast/Thermal Simulator).

Science.gov (United States)

1986-02-28

103 87 10 925 Q & T 150 126 132 ill 9 775 Q & T 180 151 163 137 7 575 AISI 4140 ANNEALED 90 76 70 59 15 Q & T 125 105 103 87 10 1025 Q & T 150 126 132...carbon steel diaphragm would be 1.9 inches thick, whereas the heat treated alloy steel diaphragm ( AISI 4130) would be 0.44 inches thick. A normalized...EXPOSURE SPEC TREAT @ RT @ 700 F @ RT @ 700 F PERCENT LIMIT ksi ksi ksi ksi in/in F LOW ALLOY STEELS AISI 4130 ANNEALED 90 76 70 59 15 Q & T 125 105

Diaphragm Effect of Steel Space Roof Systems in Hall Structures

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Mehmet FENKLİ

2015-09-01

Full Text Available Hall structures have been used widely for different purposes. They have are reinforced concrete frames and shear wall with steel space roof systems. Earthquake response of hall structures is different from building type structures. One of the most critical nodes is diaphragm effect of steel space roof on earthquake response of hall structures. Diaphragm effect is depending on lateral stiffness capacity of steel space roof system. Lateral stiffness of steel space roof system is related to modulation geometry, support conditions, selected sections and system geometry. In current paper, three representative models which are commonly used in Turkey were taken in to account for investigation. Results of numerical tests were present comparatively

Computerized videokeratoscopy contact lens software for RGP fitting in a bilateral postkeratoplasty patient: a clinical case report.

Science.gov (United States)

Szczotka, L B; Reinhart, W

1995-01-01

Computerized videokeratoscopy systems now allow interactive rigid gas permeable (RGP) fitting evaluation using fluorescein pattern simulations through updated software programs. We used Computed Anatomy's Topographic Modeling System-1 (TMS-1) Custom Design Contact Lens Program successfully to refit a symptomatic bilateral post-penetrating keratoplasty patient. No trial lenses were used. For each eye the base curve, optic zone size, and edge lift were chosen from the optimal fluorescein pattern designed and titrated on the TMS-1 unit. Lens powers were based on the patient's previous lenses and overrefraction. Dispensed lenses provided a clinically acceptable fit, good comfort, and maximal visual acuity, and no adjustments were necessary. Corneal videokeratoscopy can be successfully employed to titrate an RGP fit, even on irregular corneas.

Altered DNA Methylation and Expression Profiles of 8-Oxoguanine DNA Glycosylase 1 in Lens Tissue from Age-related Cataract Patients.

Science.gov (United States)

Wang, Yong; Li, Fei; Zhang, Guowei; Kang, Lihua; Qin, Bai; Guan, Huaijin

2015-01-01

Oxidative stress and DNA damage contribute to the pathogenesis of age-related cataract (ARC). Most oxidative DNA lesions are repaired via the base excision repair (BER) proteins including 8-oxoguanine DNA glycosylase 1 (OGG1). This study examined DNA methylation of CpG islands upstream of OGG1 and their relation to the gene expression in lens cortex from ARC patients. The clinical case-control study consisted of 15 cortical type of ARC patients and 15 age-matched non-ARC controls who received transparent lens extraction due to vitreoretinal diseases. OGG1 expression in lens cortex was analyzed by qRT-PCR and Western blot. The localization and the proportion of cells positive for OGG1 were determined by immunofluorescence. Bisulfite-sequencing PCR (BSP) was performed to evaluate the methylation status of CpG islands near OGG1 in DNA extracted from lens cortex. To test relationship between the methylation and the expression of the gene of interest, 5-Aza-2'-deoxycytidine (5-Aza-dC) was used to induce demethylation of cultured human lens epithelium B-3 (HLE B-3). To test the role of OGG1 in the repair of cellular damage, HLE B-3 was transfected with OGG1 vector, followed by ultraviolet radiation b (UVB) exposure to induce apoptosis. The mRNA and protein levels of OGG1 were significantly reduced in the lens cortex of ARC. Immunofluorescence showed that the proportion of OGG1-positive cells decreased significantly in ARC cortex in comparison with the control. The CpG island in first exon of OGG1 displayed hypermethylation in the DNA extracted from the lens cortex of ARC. Treatment of HLEB-3 cells with 5-Aza-dC upregulated OGG1 expression. UVB-induced apoptosis was attenuated after transfection with OGG1. A reduced OGG1 expression was correlated with hypermethylation of a CpG island of OGG1 in lens cortex of ARC. The role of epigenetic change in OGG1 gene in the susceptibility to oxidative stress induced cortical ARC is warranted to further study.

Acquired relaxation of the right half of the diaphragm

International Nuclear Information System (INIS)

Tolmachev, V.V.; Romadanov, A.A.

1997-01-01

Case is described of the development of complete relaxation of the right half of diaphragm following inflammatory respiratory disease accompanied by infections neuritis involving right phrenic nerve. Results of biomedical radiography and computerized tomography in dynamics are presented

Contrast sensitivity after refractive lens exchange with a multifocal diffractive aspheric intraocular lens

Directory of Open Access Journals (Sweden)

Teresa Ferrer-Blasco

2013-04-01

Full Text Available PURPOSE: To evaluate distance and near contrast sensitivity (CS under photopic and mesopic conditions before and after refractive lens exchange (RLE and implantation of the aspheric AcrySof®ReSTOR® (SN6AD3 model intraocular lens (IOL. METHODS:Seventy-four eyes of 37 patients after RLE underwent bilateral implantation with the aspheric AcrySof ReSTOR IOL. The patient sample was divided into myopic and hyperopic groups. Monocular uncorrected visual acuity at distance and near (UCVA and UCNVA, respectively and monocular best corrected visual acuity at distance and near (BCVA and BCNVA, respectively were measured before and 6 months postoperatively. Monocular CS function was measured at three different luminance levels (85, 5 and 2.5 cd/m² before and after RLE. Post-implantation results at 6 months were compared with those found before surgery. RESULTS: Our results revealed that patients in both groups obtained good UCVA and BCVA after RLE at distance and near vision in relation to pre-surgery values. No statistically significant differences were found between the values of CS pre and post-RLE at distance and near, at any lighting condition and spatial frequency (p>0.002. CONCLUSIONS: Refractive lens exchange with aspheric AcrySof ReSTOR IOL in myopic and hyperopic population provided good visual function and yield good distance and near CS under photopic and mesopic conditions.

TU-E-201-02: Eye Lens Dosimetry From CT Perfusion Studies

Energy Technology Data Exchange (ETDEWEB)

Zhang, D. [Toshiba America Medical Systems (United States)

2015-06-15

Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bomb survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on

TU-E-201-02: Eye Lens Dosimetry From CT Perfusion Studies

International Nuclear Information System (INIS)

Zhang, D.

2015-01-01

Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bomb survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on

Thermal Stresses Analysis and Optimized TTP Processes to Achieved CNT-Based Diaphragm for Thin Panel Speakers

Directory of Open Access Journals (Sweden)

Feng-Min Lai

2016-01-01

Full Text Available Industrial companies popularly used the powder coating, classing, and thermal transfer printing (TTP technique to avoid oxidation on the metallic surface and stiffened speaker diaphragm. This study developed a TTP technique to fabricate a carbon nanotubes (CNTs stiffened speaker diaphragm for thin panel speaker. The self-developed TTP stiffening technique did not require a high curing temperature that decreased the mechanical property of CNTs. In addition to increasing the stiffness of diaphragm substrate, this technique alleviated the middle and high frequency attenuation associated with the smoothing sound pressure curve of thin panel speaker. The advantage of TTP technique is less harmful to the ecology, but it causes thermal residual stresses and some unstable connections between printed plates. Thus, this study used the numerical analysis software (ANSYS to analyze the stress and thermal of work piece which have not delaminated problems in transfer interface. The Taguchi quality engineering method was applied to identify the optimal manufacturing parameters. Finally, the optimal manufacturing parameters were employed to fabricate a CNT-based diaphragm, which was then assembled onto a speaker. The result indicated that the CNT-based diaphragm improved the sound pressure curve smoothness of the speaker, which produced a minimum high frequency dip difference (ΔdB value.

ASSESSMENT OF LENS THICKNESS IN ANGLE CLOSURE DISEASE

Directory of Open Access Journals (Sweden)

Nishat Sultana Khayoom

2016-08-01

Full Text Available BACKGROUND Anterior chamber depth and lens thickness have been considered as important biometric determinants in primary angle-closure glaucoma. Patients with primary narrow angle may be classified as a primary angle closure suspect (PACS, or as having primary angle closure (PAC or primary angle closure glaucoma (PACG. 23.9% of patients with primary angle closure disease are in India, which highlights the importance of understanding the disease, its natural history, and its underlying pathophysiology, so that we may try to establish effective methods of treatment and preventative measures to delay, or even arrest, disease progression, thereby reducing visual morbidity. AIM To determine the lens thickness using A-scan biometry and its significance in various stages of angle closure disease. MATERIALS AND METHODS Patients attending outpatient department at Minto Ophthalmic Hospital between October 2013 to May 2015 were screened for angle closure disease and subsequently evaluated at glaucoma department. In our study, lens thickness showed a direct correlation with shallowing of the anterior chamber by determining the LT/ ACD ratio. A decrease in anterior chamber depth is proportional to the narrowing of the angle which contributes to the progression of the angle closure disease from just apposition to occlusion enhancing the risk for optic nerve damage and visual field loss. Hence, if the lens thickness values are assessed earlier in the disease process, appropriate intervention can be planned. CONCLUSION Determination of lens changes along with anterior chamber depth and axial length morphometrically can aid in early detection of angle closure. The role of lens extraction for PACG is a subject of increased interest. Lens extraction promotes the benefits of anatomical opening of the angle, IOP reduction and improved vision. This potential intervention may be one among the armamentarium of approaches for PACG. Among the current treatment modalities

Acceptability of an existing, female-controlled contraceptive method that could potentially protect against HIV: a comparison of diaphragm users and other method users.

Science.gov (United States)

Bird, Sheryl Thorburn; Harvey, S Marie; Maher, Julie E; Beckman, Linda J

2004-01-01

The diaphragm, an internal barrier contraceptive device, is a candidate for a female-controlled method for preventing human immunodeficiency virus (HIV) and other sexually transmitted infections (STIs). This study's objective was to examine how women who use the diaphragm differ from women using the pill and/or condoms with respect to factors hypothesized to influence the acceptability of contraceptive methods. Our goal was to increase understanding of who finds the diaphragm acceptable and why. We conducted a cross-sectional telephone survey with selected female members of a managed care organization. For this analysis, we limited the sample to 585 women currently using the diaphragm (n = 196), pill (n = 200), condoms (n = 132), or pill and condoms (n = 57). We conducted bivariate analyses and multinomial logistic regression analyses to assess the associations between selected characteristics and diaphragm use. Diaphragm use was significantly associated with several variables. Of particular interest, placing less importance on hormonal method characteristics was significantly associated with diaphragm use (versus use of the pill, condoms, or both). Placing more importance on barrier method attributes was significantly associated with diaphragm use (versus pill use, alone or with condoms). In addition, lower condom use self-efficacy was significantly associated with diaphragm use (versus condom use, alone or with pill). Lack of motivation to avoid HIV/STIs was significantly associated with using the diaphragm versus condoms (only). These results have important implications for future research, interventions, counseling strategies for providers, and product development. Our findings suggest that if the diaphragm protects against HIV, it could be a desirable option for some women.

Combined 23-gauge transconjunctival vitrectomy and scleral fixation of intraocular lens without conjunctival dissection in managing lens complications.

Science.gov (United States)

Yeung, Ling; Wang, Nan-Kai; Wu, Wei-Chi; Chen, Kuan-Jen

2018-04-23

To evaluate the safety and efficacy of combined 23-gauge transconjunctival pars plana vitrectomy and scleral fixation of intraocular lens (IOL) without conjunctival dissection. A retrospective study in Chang Gung Memorial Hospital, Keelung and Taoyuan, Taiwan. Patients receiving combined 23-gauge transconjunctival pars plana vitrectomy and scleral fixation of IOL without conjunctival dissection were enrolled. The ocular findings, causes of lens complication, surgical procedures, type of IOL used, and complications were documented. We included 40 eyes from 39 patients (27 male, 12 female) with a mean age of 59.5 [standard deviation (±) 14.8] years old. The mean follow-up duration was 6.8 ± 5.4 months. The cause of lens complications was ocular trauma in 24 (60%) eyes, cataract surgery complications in 11 (28%) eyes, and spontaneous subluxation of crystalline lens in 5 (13%) eyes. The overall best corrected visual acuity (BCVA) (logMAR) improved from 1.359 ± 0.735 to 0.514 ± 0.582 (p IOL decentration was found in 3 (8%) eyes and 1 (3%) eye respectively. Combined 23-gauge transconjunctival vitrectomy and scleral fixation of IOL without conjunctival dissection is effective and safe in managing a wide variety of lens complications, with good postoperative comfort and visual recovery. Retrospective study, not applicable.

Hydrogel based sensor arrays (2 × 2) with perforated piezoresistive diaphragms for metabolic monitoring (in vitro).

Science.gov (United States)

Orthner, M P; Lin, G; Avula, M; Buetefisch, S; Magda, J; Rieth, L W; Solzbacher, F

2010-03-19

This report details the first experimental results from novel hydrogel sensor array (2 × 2) which incorporates analyte diffusion pores into a piezoresistive diaphragm for the detection of hydrogel swelling pressures and hence chemical concentrations. The sensor assembly was comprised of three components, the active four sensors, HPMA/DMA/TEGDMA (hydroxypropyl methacrylate (HPMA), N,N-dimethylaminoethyl methacrylate (DMA) and crosslinker tetra-ethyleneglycol dimethacrylate (TEGDMA)) hydrogel, and backing plate. Each of the individual sensors of the array can be used with various hydrogels used to measure the presence of a number of stimuli including pH, ionic strength, and glucose concentrations. Ideally, in the future, these sensors will be used for continuous metabolic monitoring applications and implanted subcutaneously. In this paper and to properly characterize the sensor assembly, hydrogels sensitive to changes ionic strength were synthesized using hydroxypropyl methacrylate (HPMA), N,N-dimethylaminoethyl methacrylate (DMA) and crosslinker tetra-ethyleneglycol dimethacrylate (TEGDMA) and inserted into the sensor assembly. This hydrogel quickly and reversibly swells when placed environments of physiological buffer solutions (PBS) with ionic strengths ranging from 0.025 to 0.15 M, making it ideal for proof-of-concept testing and initial characterization. The assembly was wire bonded to a printed circuit board and coated with 3 ± 0.5 μm of Parylene-C using chemical vapor deposition (CVD) to protect the sensor and electrical connections during ionic strength wet testing. Two versions of sensors were fabricated for comparison, the first incorporated diffusion pores into the diaphragm, and the second used a solid diaphragm with perforated backing plate. This new design (perforated diaphragm) was shown to have slightly higher sensitivity than solid diaphragm sensors with separate diffuse backing plates when coupled with the hydrogel. The sensitivities for the 1 mm

Intravitreal Phacoemulsification Using Torsional Handpiece for Retained Lens Fragments

OpenAIRE

Kumar, Vinod; Takkar, Brijesh

2016-01-01

Purpose: To evaluate the results of intravitreal phacoemulsification with torsional hand piece in eyes with posteriorly dislocated lens fragments. Methods: In this prospective, interventional case series, 15 eyes with retained lens fragments following phacoemulsification were included. All patients underwent standard three-port pars plana vitrectomy and intravitreal phacoemulsification using sleeveless, torsional hand piece (OZiL™, Alcon's Infiniti Vision System). Patients were followed up...

Scattering study at free air ionization chamber diaphragm

International Nuclear Information System (INIS)

Santos, Alexandre Lo Bianco dos

2011-01-01

The maim of this work consisted in the assessment of the correction factor for air kerma, due to scattered radiation in the diaphragm of the free-air ionization chamber model 481. LNMRl measurements were made to acquire x-ray spectra corresponding to the Qualities RQR-M, described in IEC 61627 standards (2005). These spectra were used as input data in the MC simulations. The operational range of energy spectra provide up to 35 keV. This energy range is typically used in diagnostic radiology, although there is not primary standard for air kerma. The determination of this factor is a fundamental process in the primary standardization of the air kerma. These factors were obtained by computer simulation using the Penelope code. The results are k RQR-M1 =0,9946, k RQR -M2 =0,9932, k RQR-M3 =0,9978 and k RQR-M4 =0,9885; with uncertainties of 0,007 and coverage factor equal to 2. lt can be concluded that, with respect to the diaphragm, the chamber can be used in the primary standard of air kerma. (author)

Assessment of Diaphragm and External Intercostals Fatigue from Surface EMG using Cervical Magnetic Stimulation

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Ya-Ju Chang

2008-03-01

Full Text Available This study was designed: (1 to test the reliability of surface electromyography (sEMG recording of the diaphragm and external intercostals contractions response to cervical magnetic stimulation (CMS, (2 to examine the amount and the types of inspiratory muscle fatigue that developed after maximum voluntary ventilation (MVV maneuvers.Ten male college students without physical disability (22.1±2.0 years old participated in the study and each completed a control (quiet breathing trial and a fatigue (MVV maneuvers trial sequentially. In the quiet breathing trial, the subjects maintained quiet breathing for five minutes. The subjects performed five maximal static inspiratory efforts and received five CMS before and after the quiet breathing. In the MVV trial, subjects performed five maximal inspiratory efforts and received five CMS before, immediately after, and ten minutes after two sets of MVV maneuvers performed five minutes apart. Maximal inspiratory pressure (PImax, sEMG of diaphragm and external intercostals during maximal static inspiratory efforts and during CMS were recorded. In the quiet breathing trial, high intraclass correlation coefficients (ICC=0.95-0.99 were observed in all the variables. In the MVV trial, the PImax, the EMG amplitude and the median power frequency during maximal static inspiratory efforts significantly decreased in both the diaphragm and the external intercostals immediately after the MVV maneuvers Sensors 2008, 8 2175 (P 0.05. It is concluded that the sEMG recordings of the diaphragm during maximal static inspiratory efforts and in response to CMS allow reproducible sequential assessment of diaphragm contractility. MVV maneuvers resulted in inspiratory muscles fatigue, possibly central fatigue.

Disposable contact lens use as a risk factor for microbial keratitis

OpenAIRE

Radford, C.; Minassian, D.; Dart, J.

1998-01-01

AIMS—A case-control study was performed to evaluate soft contact lens (SCL) wear modality as a risk factor for microbial keratitis.
METHODS—Contact lens wearers presenting as new patients to Moorfields Eye Hospital accident and emergency department during a 12 month period completed a self administered questionnaire detailing demographic data and contact lens use habits. Cases were patients with a clinical diagnosis of SCL related microbial keratitis. Controls were SCL users attending with di...

Diaphragm remodeling and compensatory respiratory mechanics in a canine model of Duchenne muscular dystrophy.

Science.gov (United States)

Mead, A F; Petrov, M; Malik, A S; Mitchell, M A; Childers, M K; Bogan, J R; Seidner, G; Kornegay, J N; Stedman, H H

2014-04-01

Ventilatory insufficiency remains the leading cause of death and late stage morbidity in Duchenne muscular dystrophy (DMD). To address critical gaps in our knowledge of the pathobiology of respiratory functional decline, we used an integrative approach to study respiratory mechanics in a translational model of DMD. In studies of individual dogs with the Golden Retriever muscular dystrophy (GRMD) mutation, we found evidence of rapidly progressive loss of ventilatory capacity in association with dramatic morphometric remodeling of the diaphragm. Within the first year of life, the mechanics of breathing at rest, and especially during pharmacological stimulation of respiratory control pathways in the carotid bodies, shift such that the primary role of the diaphragm becomes the passive elastic storage of energy transferred from abdominal wall muscles, thereby permitting the expiratory musculature to share in the generation of inspiratory pressure and flow. In the diaphragm, this physiological shift is associated with the loss of sarcomeres in series (∼ 60%) and an increase in muscle stiffness (∼ 900%) compared with those of the nondystrophic diaphragm, as studied during perfusion ex vivo. In addition to providing much needed endpoint measures for assessing the efficacy of therapeutics, we expect these findings to be a starting point for a more precise understanding of respiratory failure in DMD.

Experimental validation of the tuneable diaphragm effect in modern acoustic stethoscopes.

Science.gov (United States)

Nowak, Karolina M; Nowak, Lukasz J

2017-09-01

The force with which the diaphragm chestpiece of a stethoscope is pressed against the body of a patient during an auscultation examination introduces the initial stress and deformation to the diaphragm and the underlying tissues, thus altering the acoustic parameters of the sound transmission path. If the examination is performed by an experienced physician, he will intuitively adjust the amount of the force in order to achieve the optimal sound quality. However, in case of becoming increasingly popular auto-diagnosis and telemedicine auscultation devices with no such feedback mechanisms, the question arises regarding the influence of the possible force mismatch on the parameters of the recorded signal. The present study describes the results of the experimental investigations on the relation between pressure applied to the chestpiece of a stethoscope and parameters of the transmitted bioacoustic signals. The experiments were carried out using various stethoscopes connected to a force measurement system, which allowed to maintain fixed pressure during auscultation examinations. The signals were recorded during examinations of different volunteers, at various auscultation sites. The obtained results reveal strong individual and auscultation-site variability. It is concluded that the underlying tissue deformation is the primary factor that alters the parameters of the recorded signals. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Extra Lobes of Liver and Congenital Anomalies of Diaphragm in Children

Directory of Open Access Journals (Sweden)

I.P. Zhurylo

2014-09-01

Full Text Available The literature data on hepatic congenital anomalies in children are summarized in this article. Three clinical observations of transposition of extra lobe of the liver (ELL into the thoracic cavity in children were analyzed. The true diaphragmatic hernia was found in all cases. Clinical manifestations of this disease depend on the severity of the compression of mediastinum organs. Indications for surgical correction were determined individually. ELL move into the abdominal cavity, excision of the hernia sac and alloplasty of the diaphragmatic defect were performed for one patient. Possible mechanisms for the formation of these complex congenital malformations were discussed based on the comparison of clinical data with the stages of embryogenesis liver, diaphragm and heart.

A Correlation of Thin Lens Approximation to Thick Lens Design by Using Coddington Factors in Lens Design and Manufacturing

OpenAIRE

FARSAKOĞLU, Ö. Faruk

2014-01-01

The effect of Coddington factors on aberration functions has been analysed using thin lens approximation. Minimizing spherical aberrations of singlet lenses using Coddington factors in lens design depending on lens manufacturing is discussed. Notation of lens test plate pairs used in lens manufacturing is also presented in terms of Coddington shape factors.

THE EFFECT OF INNER DIAPHRAGMS AND NON-CONTINUOUS SILL SECTION ON THE STIFFNESS OF AUTOMOTIVE B-PILLAR

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C.F. Tan

2017-11-01

Full Text Available The paper discusses the knowledge on the behaviour of T-frame under specific loading will be obtained by experimental methods in order to investigate the deflection of the vehicle B-pillar or T-frame. In addition, a series of T-frame were designed with inner diaphragm at various location in the sill member in order to investigate the effect of inner diaphragm and noncontinuous closed hat section in the sill member. Lastly, the results from the experimental tests were compared with the finite element analysis results to demonstrate the effectiveness of the inner diaphragm in the automotive B-pillar.

Reinforcement of the pelvic diaphragm using a purse-string suture in dogs: description of technique

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P.C. Moraes

Full Text Available ABSTRACT Recurrence of perineal hernias is frequent, and is associated to poor identification of anatomical structures during surgery, inadequate suture placement, and failure of physical support of the pelvic diaphragm after surgical reconstruction. The objective of this work is to describe a novel surgical technique for reinforcement of the pelvic diaphragm after performing the internal obturator transposition technique in dogs with perineal hernia.

Overexpression of antioxidant enzymes in diaphragm muscle does not alter contraction-induced fatigue or recovery

Science.gov (United States)

McClung, Joseph M.; DeRuisseau, Keith C.; Whidden, Melissa A.; Van Remmen, Holly; Richardson, Arlan; Song, Wook; Vrabas, Ioannis S.; Powers, Scott K.

2010-01-01

Low levels of reactive oxygen species (ROS) production are necessary to optimize muscle force production in unfatigued muscle. In contrast, sustained high levels of ROS production have been linked to impaired muscle force production and contraction-induced skeletal muscle fatigue. Using genetically engineered mice, we tested the hypothesis that the independent transgenic overexpression of catalase (CAT), copper/zinc superoxide dismutase (CuZnSOD; SOD1) or manganese superoxide dismutase (MnSOD; SOD2) antioxidant enzymes would negatively affect force production in unfatigued diaphragm muscle but would delay the development of muscle fatigue and enhance force recovery after fatiguing contractions. Diaphragm muscle from wild-type littermates (WT) and from CAT, SOD1 and SOD2 overexpressing mice were subjected to an in vitro contractile protocol to investigate the force–frequency characteristics, the fatigue properties and the time course of recovery from fatigue. The CAT, SOD1 and SOD2 overexpressors produced less specific force (in N cm−2) at stimulation frequencies of 20–300 Hz and produced lower maximal tetanic force than WT littermates. The relative development of muscle fatigue and recovery from fatigue were not influenced by transgenic overexpression of any antioxidant enzyme. Morphologically, the mean cross-sectional area (in μm2) of diaphragm myofibres expressing myosin heavy chain type IIA was decreased in both CAT and SOD2 transgenic animals, and the percentage of non-contractile tissue increased in diaphragms from all transgenic mice. In conclusion, our results do not support the hypothesis that overexpression of independent antioxidant enzymes protects diaphragm muscle from contraction-induced fatigue or improves recovery from fatigue. Moreover, our data are consistent with the concept that a basal level of ROS is important to optimize muscle force production, since transgenic overexpression of major cellular antioxidants is associated with

Piggyback intraocular lens implantation to correct pseudophakic refractive error after segmental multifocal intraocular lens implantation.

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Venter, Jan A; Oberholster, Andre; Schallhorn, Steven C; Pelouskova, Martina

2014-04-01

To evaluate refractive and visual outcomes of secondary piggyback intraocular lens implantation in patients diagnosed as having residual ametropia following segmental multifocal lens implantation. Data of 80 pseudophakic eyes with ametropia that underwent Sulcoflex aspheric 653L intraocular lens implantation (Rayner Intraocular Lenses Ltd., East Sussex, United Kingdom) to correct residual refractive error were analyzed. All eyes previously had in-the-bag zonal refractive multifocal intraocular lens implantation (Lentis Mplus MF30, models LS-312 and LS-313; Oculentis GmbH, Berlin, Germany) and required residual refractive error correction. Outcome measurements included uncorrected distance visual acuity, corrected distance visual acuity, uncorrected near visual acuity, distance-corrected near visual acuity, manifest refraction, and complications. One-year data are presented in this study. The mean spherical equivalent ranged from -1.75 to +3.25 diopters (D) preoperatively (mean: +0.58 ± 1.15 D) and reduced to -1.25 to +0.50 D (mean: -0.14 ± 0.28 D; P < .01). Postoperatively, 93.8% of eyes were within ±0.50 D and 98.8% were within ±1.00 D of emmetropia. The mean uncorrected distance visual acuity improved significantly from 0.28 ± 0.16 to 0.01 ± 0.10 logMAR and 78.8% of eyes achieved 6/6 (Snellen 20/20) or better postoperatively. The mean uncorrected near visual acuity changed from 0.43 ± 0.28 to 0.19 ± 0.15 logMAR. There was no significant change in corrected distance visual acuity or distance-corrected near visual acuity. No serious intraoperative or postoperative complications requiring secondary intraocular lens removal occurred. Sulcoflex lenses proved to be a predictable and safe option for correcting residual refractive error in patients diagnosed as having pseudophakia. Copyright 2014, SLACK Incorporated.

PO2 cycling reduces diaphragm fatigue by attenuating ROS formation.

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Zuo, Li; Diaz, Philip T; Chien, Michael T; Roberts, William J; Kishek, Juliana; Best, Thomas M; Wagner, Peter D

2014-01-01

Prolonged muscle exposure to low PO2 conditions may cause oxidative stress resulting in severe muscular injuries. We hypothesize that PO2 cycling preconditioning, which involves brief cycles of diaphragmatic muscle exposure to a low oxygen level (40 Torr) followed by a high oxygen level (550 Torr), can reduce intracellular reactive oxygen species (ROS) as well as attenuate muscle fatigue in mouse diaphragm under low PO2. Accordingly, dihydrofluorescein (a fluorescent probe) was used to monitor muscular ROS production in real time with confocal microscopy during a lower PO2 condition. In the control group with no PO2 cycling, intracellular ROS formation did not appear during the first 15 min of the low PO2 period. However, after 20 min of low PO2, ROS levels increased significantly by ∼30% compared to baseline, and this increase continued until the end of the 30 min low PO2 condition. Conversely, muscles treated with PO2 cycling showed a complete absence of enhanced fluorescence emission throughout the entire low PO2 period. Furthermore, PO2 cycling-treated diaphragm exhibited increased fatigue resistance during prolonged low PO2 period compared to control. Thus, our data suggest that PO2 cycling mitigates diaphragm fatigue during prolonged low PO2. Although the exact mechanism for this protection remains to be elucidated, it is likely that through limiting excessive ROS levels, PO2 cycling initiates ROS-related antioxidant defenses.

PO2 cycling reduces diaphragm fatigue by attenuating ROS formation.

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Li Zuo

Full Text Available Prolonged muscle exposure to low PO2 conditions may cause oxidative stress resulting in severe muscular injuries. We hypothesize that PO2 cycling preconditioning, which involves brief cycles of diaphragmatic muscle exposure to a low oxygen level (40 Torr followed by a high oxygen level (550 Torr, can reduce intracellular reactive oxygen species (ROS as well as attenuate muscle fatigue in mouse diaphragm under low PO2. Accordingly, dihydrofluorescein (a fluorescent probe was used to monitor muscular ROS production in real time with confocal microscopy during a lower PO2 condition. In the control group with no PO2 cycling, intracellular ROS formation did not appear during the first 15 min of the low PO2 period. However, after 20 min of low PO2, ROS levels increased significantly by ∼30% compared to baseline, and this increase continued until the end of the 30 min low PO2 condition. Conversely, muscles treated with PO2 cycling showed a complete absence of enhanced fluorescence emission throughout the entire low PO2 period. Furthermore, PO2 cycling-treated diaphragm exhibited increased fatigue resistance during prolonged low PO2 period compared to control. Thus, our data suggest that PO2 cycling mitigates diaphragm fatigue during prolonged low PO2. Although the exact mechanism for this protection remains to be elucidated, it is likely that through limiting excessive ROS levels, PO2 cycling initiates ROS-related antioxidant defenses.

The Effects of Phrenic Nerve Degeneration by Axotomy and Crush on the Electrical Activities of Diaphragm Muscles of Rats.

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Alkiş, Mehmet Eşref; Kavak, Servet; Sayır, Fuat; Him, Aydin

2016-03-01

The aim of this study was to investigate the effect of axotomy and crush-related degeneration on the electrical activities of diaphragm muscle strips of experimental rats. In the present study, twenty-one male Wistar-albino rats were used and divided into three groups. The animals in the first group were not crushed or axotomized and served as controls. Phrenic nerves of the rats in the second and third groups were crushed or axotomized in the diaphragm muscle. Resting membrane potential (RMP) was decreased significantly in both crush and axotomy of diaphragm muscle strips of experimental rats (p phrenic nerves may produce electrical activities in the diaphragm muscle of the rat by depolarization time and half-repolarization time prolonged in crush and axotomy rats.

Immunohistochemical studies of lens crystallins in the dysgenetic lens (dyl) mutant mice

NARCIS (Netherlands)

Brahma, S.K.; Sanyal, S.

1984-01-01

The lens in the dyl mutant mice shows a persistent lens-ectodermal connection as well as degeneration and extrusion of lens materials after the initial differentiation of the fibres. Immunohistochemical investigation of the ontogeny of the lens crystallins in this developing mutant lens has been

Assessing the need for intermediate diaphragms in prestressed concrete bridges.

Science.gov (United States)

2008-03-01

Reinforced concrete intermediate diaphragms (IDs) are currently being used in prestressed concrete (PC) girder bridges in Louisiana. Some of the advantages of providing IDs are disputed in the bridge community; the use of IDs increases the cost and t...

Sharing of secondary electrons by in-lens and out-lens detector in low-voltage scanning electron microscope equipped with immersion lens.

Science.gov (United States)

Kumagai, Kazuhiro; Sekiguchi, Takashi

2009-03-01

To understand secondary electron (SE) image formation with in-lens and out-lens detector in low-voltage scanning electron microscopy (LV-SEM), we have evaluated SE signals of an in-lens and an out-lens detector in LV-SEM. From the energy distribution spectra of SEs with various boosting voltages of the immersion lens system, we revealed that the electrostatic field of the immersion lens mainly collects electrons with energy lower than 40eV, acting as a low-pass filter. This effect is also observed as a contrast change in LV-SEM images taken by in-lens and out-lens detectors.

Degeneration of Phrenic Motor Neurons Induces Long-Term Diaphragm Deficits following Mid-Cervical Spinal Contusion in Mice

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Nicaise, Charles; Putatunda, Rajarshi; Hala, Tamara J.; Regan, Kathleen A.; Frank, David M.; Brion, Jean-Pierre; Leroy, Karelle; Pochet, Roland; Wright, Megan C.

2012-01-01

Abstract A primary cause of morbidity and mortality following cervical spinal cord injury (SCI) is respiratory compromise, regardless of the level of trauma. In particular, SCI at mid-cervical regions targets degeneration of both descending bulbospinal respiratory axons and cell bodies of phrenic motor neurons, resulting in deficits in the function of the diaphragm, the primary muscle of inspiration. Contusion-type trauma to the cervical spinal cord is one of the most common forms of human SCI; however, few studies have evaluated mid-cervical contusion in animal models or characterized consequent histopathological and functional effects of degeneration of phrenic motor neuron–diaphragm circuitry. We have generated a mouse model of cervical contusion SCI that unilaterally targets both C4 and C5 levels, the location of the phrenic motor neuron pool, and have examined histological and functional outcomes for up to 6 weeks post-injury. We report that phrenic motor neuron loss in cervical spinal cord, phrenic nerve axonal degeneration, and denervation at diaphragm neuromuscular junctions (NMJ) resulted in compromised ipsilateral diaphragm function, as demonstrated by persistent reduction in diaphragm compound muscle action potential amplitudes following phrenic nerve stimulation and abnormalities in spontaneous diaphragm electromyography (EMG) recordings. This injury paradigm is reproducible, does not require ventilatory assistance, and provides proof-of-principle that generation of unilateral cervical contusion is a feasible strategy for modeling diaphragmatic/respiratory deficits in mice. This study and its accompanying analyses pave the way for using transgenic mouse technology to explore the function of specific genes in the pathophysiology of phrenic motor neuron degeneration and respiratory dysfunction following cervical SCI. PMID:23176637

Lens subluxation grading system: predictive value for ectopia lentis surgical outcomes

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Mauro Waiswol

2009-03-01

Full Text Available Objective: To present a classification system to grade ectopia lentis and to assess its usefulness as a predictor for surgical outcomes. Methods: Fifty-one eyes of 28 patients with either simple (19 patients or Marfan syndrome-associated ectopia lentis (nine patients with variable degrees of subluxation were operated on. Lens subluxation intensity was graded according to the lens subluxation grading system (LSGS from grade 1 (lens on the whole pupillary area up to grade 4 (lens absent from the pupillary area. Thirty eyes underwent cataract extraction (“dry” aspiration with endocapsular ring and in-the-bag intraocular lens (IOL implantation. Twenty-one eyes underwent cataract extraction (“dry” aspiration with scleral fixation of the IOL. The predictive value of the LSGS was assessed by analyzing the post-operative outcomes, including visual acuity (VA, endothelial cell loss, and complications for each grade on the grading system. Rresults: Patients were classified into grade 1 (19.6%, grade 2 (51% and grade 3 (29.4%. Post-operative VA was lower for eyes with larger degrees of subluxation. The higher the subluxation grade, the higher the endothelial cell loss, as well as, the frequency of vitreous loss and surgical time. Higher subluxation grades prevented optimal surgical outcomes with endocapsular ring and in-the-bag IOL implantation. Cconclusions: The LSGS provides an estimate of the surgical success of ectopia lentis. Adequate standardization of lens subluxation is crucial for understanding studies dealing with the surgical correction of this disorder.

Clinical observation of Artisan iris-clip intraocular lens implantation at stage Ⅰ

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Qing Zhou

2014-09-01

Full Text Available AIM: To observe the clinical efficacy of Artisan iris-clip intraocular lens(IOLimplantation on cataract with a wide range of lens dislocation.METHODS: Twenty-four hospital patients(28 eyesof cataract with lens subluxation by trauma(20 patients, 20 eyesand Marfan's syndrome(4 patients, 8 eyesduring May 2007 to December 2011 were selected. All of them underwent phacoemulsification or an anterior vitrectomy and Artisan iris-clip IOL implantation at stage Ⅰ. Postoperative visual acuity, corneal endothelial cell count, intraocular lens position and postoperative complications were observed. Follow-up time was 6mo.RESULTS:Compared with the preoperative, postoperative best corrected visual acuity improved to varying degrees, visual acuity of 0.1-0.5 was in 20 eyes, 0.5-1.0 in 8 eyes. After followed up 1-6mo, no artificial lens shift, iris inflammation, iris atrophy and corneal decompensation and other complications were observed.CONCLUSION: Cataract surgery with a wide range of lens dislocation is difficult, but as long as surgeons who have a wealth of clinical experience and superb skills, still can carry out phacoemulsification surgery or anterior vitrectomy and Artisan iris-clip IOL implantation and obtain a better outcome.

Surgical treatment of hereditary lens subluxations.

Science.gov (United States)

Ozdek, Sengul; Sari, Ayca; Bilgihan, Kamil; Akata, Fikret; Hasanreisoglu, Berati

2002-01-01

To evaluate the effectiveness and results of pars plana vitreolensectomy approach with transscleral fixation of intraocular lens in hereditary lens subluxations. Fifteen eyes of 9 consecutive patients with a mean age of 12.8+/-6.2 years (6-26 years) with hereditary lens subluxation were operated on and the results were evaluated in a prospective study. Surgery was considered if best spectacle corrected visual acuity (BSCVA) was less than 20/70. All eyes underwent a 2-port pars plana vitreolensectomy and transscleral fixation of an intraocular lens (IOL). The mean follow-up period was 12.6+/-7.5 months (6-22 months). There was no major intraoperative complication. Preoperatively, 8 eyes (53.3%) had a BSCVA of counting fingers (CF) and 7 eyes (46.6%) had a BSCVA of 20/200 to 20/70. Postoperatively, 14 eyes (93.3%) had a BSCVA of 20/50 or better. None of the patients had IOL decentration or intraocular pressure (IOP) increase during the follow-up period. There was a macular hole formation in 1 eye postoperatively. The early results of pars plana vitreolensectomy with IOL implantation using scleral fixation technique had shown that it not only promises a rapid visual rehabilitation but it is also a relatively safe method. More serious complications, however, may occur in the long term.

Scharioth Macula Lens: A new intraocular implant for low-vision patients with stabilized maculopathy- first experience.

Science.gov (United States)

Nekolova, Jana; Rozsival, Pavel; Sin, Martin; Jiraskova, Nada

2017-06-01

To present the initial results of Scharioth Macula Lens (SML) implantation. The SML is a new add-on intraocular lens designed to increase uncorrected near visual acuity (UCVA) in patients with stabilized maculopathy. Eight patients were included in the study. All met the indication criteria before SML implantation. An SML was implanted in the better seeing eye. Near and distance visual acuity were tested. Possible complications and patient complaints were recorded and patients were asked about their quality of vision after SML implantation. The examination was carried out on day 1, 1 week, 1, 3 and 6 months after surgery. Six-month-results are presented. Apart from one, all patients with the SML had good near visual acuity at a recommended reading distance of 15 cm. Preoperatively, the mean (min-max) near UCVA was J13 (J8-J16), mean distance BCVA was 0.27. Postoperatively, the best results were after 1 month - near UCVA was J2.5 (J1-J7), distance BCVA was 0.26. Three months after surgery, this decreased to J4.5 (J1-J8); distance VA remained 0.25. Six months postoperatively - near vision was J4 (J1-J8) and distance VA was unchanged. Patients reported problems with reading speed and reading distance. Daily exercise improved their reading ability. One patient converted to wet AMD 3 months post-implantation. The SML is a new hope for low-vision patients. It acts as a magnifier in the eye. It is a suitable method for increasing near visual acuity in patients with inactive maculopathy.

Severe pigment dispersion after iris-claw phakic intraocular lens implantation.

Science.gov (United States)

Galvis, Virgilio; Carreño, Néstor I; Tello, Alejandro; Laiton, Andrea N

2017-12-01

A 23-year-old female patient presented 3 months after the implantation of an Artisan® phakic intraocular lens with a severe depigmentation of the iris and peripheral anterior synechiae. Explantation of the intraocular lens and goniosynechialysis were performed. Eleven months after the explantation appearance of the iris significantly improved. There was no loss of lines of corrected distance visual acuity. Severe pigment dispersion after the implantation of an Artisan® phakic intraocular lens may happen and may require explantation of the lens. Iris depigmentation may improve with time.

Severe pigment dispersion after iris-claw phakic intraocular lens implantation

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Virgilio Galvis

2017-01-01

Full Text Available A 23-year-old female patient presented 3 months after the implantation of an Artisan® phakic intraocular lens with a severe depigmentation of the iris and peripheral anterior synechiae. Explantation of the intraocular lens and goniosynechialysis were performed. Eleven months after the explantation appearance of the iris significantly improved. There was no loss of lines of corrected distance visual acuity. Severe pigment dispersion after the implantation of an Artisan® phakic intraocular lens may happen and may require explantation of the lens. Iris depigmentation may improve with time.

Eye lens dose correlations with personal dose equivalent and patient exposure in paediatric interventional cardiology performed with a fluoroscopic biplane system.

Science.gov (United States)

Alejo, L; Koren, C; Corredoira, E; Sánchez, F; Bayón, J; Serrada, A; Guibelalde, E

2017-04-01

To analyse the correlations between the eye lens dose estimates performed with dosimeters placed next to the eyes of paediatric interventional cardiologists working with a biplane system, the personal dose equivalent measured on the thorax and the patient dose. The eye lens dose was estimated in terms of H p (0.07) on a monthly basis, placing optically stimulated luminescence dosimeters (OSLDs) on goggles. The H p (0.07) personal dose equivalent was measured over aprons with whole-body OSLDs. Data on patient dose as recorded by the kerma-area product (P KA ) were collected using an automatic dose management system. The 2 paediatric cardiologists working in the facility were involved in the study, and 222 interventions in a 1-year period were evaluated. The ceiling-suspended screen was often disregarded during interventions. The annual eye lens doses estimated on goggles were 4.13±0.93 and 4.98±1.28mSv. Over the aprons, the doses obtained were 10.83±0.99 and 11.97±1.44mSv. The correlation between the goggles and the apron dose was R 2 =0.89, with a ratio of 0.38. The correlation with the patient dose was R 2 =0.40, with a ratio of 1.79μSvGy -1 cm -2 . The dose per procedure obtained over the aprons was 102±16μSv, and on goggles 40±9μSv. The eye lens dose normalized to P KA was 2.21±0.58μSvGy -1 cm -2 . Measurements of personal dose equivalent over the paediatric cardiologist's apron are useful to estimate eye lens dose levels if no radiation protection devices are typically used. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Válvula fonatória brasileira para traqueotomia: padronização de pressão de diafragma Brazilian tracheotomy speech valve: diaphragm pressure standardization

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Ângela Rúbia Oliveira Silveira

2009-02-01

Full Text Available A traqueotomia está indicada em condições com obstrução respiratória alta ou doença pulmonar obstrutiva crônica. As Válvulas Fonatórias (VF melhoram a comunicação, higienização e umidificação das vias aéreas dos pacientes traqueotomizados. OBJETIVO: Demonstrar a VF nacional, de menor custo, e sua utilização na reabilitação fonatória desses pacientes, avaliar resistência de abertura pelo diafragma, o que confere melhor conforto ao paciente. Forma de Estudo: Experimental, coorte contemporâneo. MATERIAL E MÉTODO: A VF foi utilizada em 32 pacientes. A válvula tem diafragma dentro de um corpo em aço inox com encaixes de plástico. Estudou-se grau de conforto respiratório de acordo com a resistência do diafragma da válvula, 40, 50 e 60 shores. RESULTADOS: Obteve-se uso regular da VF acoplada à cânula por todos os pacientes, 26 o fizeram por mais de 12h diárias e destes 14 por 24h diárias. A pressão do diafragma obtida foi de 40 shores para 13 pacientes e 50 shores para 19 pacientes, sem utilização de 60 shores. CONCLUSÃO: A VF metálica permite fonação, sem a oclusão digital da cânula, e respiração sob conforto. Obteve-se resistência padronizada do diafragma. Atualmente todos os pacientes do estudo utilizam estas VF com fonação e 43,75% período integral.Tracheotomy is performed in cases of upper airway obstruction or chronic pulmonary disorders. The Tracheotomy Speech Valves (TSV improve communication and airway hygiene and humidification of tracheotomized patients. AIM: To show the low cost Brazilian TSV and its use in speech rehabilitation of tracheotomized patients, to evaluate diaphragm opening resistance and comfort to the patient. Study Design: Experimental, contemporary cohort. MATERIALS AND METHODS: The TSV was used in 32 patients. The valve has a diaphragm within a stainless steel body with plastic fittings. We studied the level of respiratory comfort according to the degree of valve diaphragm

Diaphragm motion quantification in megavoltage cone-beam CT projection images.

Science.gov (United States)

Chen, Mingqing; Siochi, R Alfredo

2010-05-01

To quantify diaphragm motion in megavoltage (MV) cone-beam computed tomography (CBCT) projections. User identified ipsilateral hemidiaphragm apex (IHDA) positions in two full exhale and inhale frames were used to create bounding rectangles in all other frames of a CBCT scan. The bounding rectangle was enlarged to create a region of interest (ROI). ROI pixels were associated with a cost function: The product of image gradients and a gradient direction matching function for an ideal hemidiaphragm determined from 40 training sets. A dynamic Hough transform (DHT) models a hemidiaphragm as a contour made of two parabola segments with a common vertex (the IHDA). The images within the ROIs are transformed into Hough space where a contour's Hough value is the sum of the cost function over all contour pixels. Dynamic programming finds the optimal trajectory of the common vertex in Hough space subject to motion constraints between frames, and an active contour model further refines the result. Interpolated ray tracing converts the positions to room coordinates. Root-mean-square (RMS) distances between these positions and those resulting from an expert's identification of the IHDA were determined for 21 Siemens MV CBCT scans. Computation time on a 2.66 GHz CPU was 30 s. The average craniocaudal RMS error was 1.38 +/- 0.67 mm. While much larger errors occurred in a few near-sagittal frames on one patient's scans, adjustments to algorithm constraints corrected them. The DHT based algorithm can compute IHDA trajectories immediately prior to radiation therapy on a daily basis using localization MVCBCT projection data. This has potential for calibrating external motion surrogates against diaphragm motion.

Intravitreal Phacoemulsification Using Torsional Handpiece for Retained Lens Fragments.

Science.gov (United States)

Kumar, Vinod; Takkar, Brijesh

2016-01-01

To evaluate the results of intravitreal phacoemulsification with torsional hand piece in eyes with posteriorly dislocated lens fragments. In this prospective, interventional case series, 15 eyes with retained lens fragments following phacoemulsification were included. All patients underwent standard three-port pars plana vitrectomy and intravitreal phacoemulsification using sleeveless, torsional hand piece (OZiL™, Alcon's Infiniti Vision System). Patients were followed up for a minimum of six months to evaluate the visual outcomes and complications. The preoperative best-corrected visual acuity (BCVA) ranged from light perception to 0.3. No complications such as thermal burns of the scleral wound, retinal damage due to flying lens fragments, or difficult lens aspiration occurred during intravitreal phacoemulsification. Mean post-operative BCVA at the final follow-up was 0.5. Two eyes developed cystoid macular edema, which was managed medically. No retinal detachment was noted. Intravitreal phacoemulsification using torsional hand piece is a safe and effective alternative to conventional longitudinal phacofragmentation.

Intravitreal Phacoemulsification Using Torsional Handpiece for Retained Lens Fragments

Science.gov (United States)

Kumar, Vinod; Takkar, Brijesh

2016-01-01

Purpose: To evaluate the results of intravitreal phacoemulsification with torsional hand piece in eyes with posteriorly dislocated lens fragments. Methods: In this prospective, interventional case series, 15 eyes with retained lens fragments following phacoemulsification were included. All patients underwent standard three-port pars plana vitrectomy and intravitreal phacoemulsification using sleeveless, torsional hand piece (OZiL™, Alcon's Infiniti Vision System). Patients were followed up for a minimum of six months to evaluate the visual outcomes and complications. Results: The preoperative best-corrected visual acuity (BCVA) ranged from light perception to 0.3. No complications such as thermal burns of the scleral wound, retinal damage due to flying lens fragments, or difficult lens aspiration occurred during intravitreal phacoemulsification. Mean post-operative BCVA at the final follow-up was 0.5. Two eyes developed cystoid macular edema, which was managed medically. No retinal detachment was noted. Conclusion: Intravitreal phacoemulsification using torsional hand piece is a safe and effective alternative to conventional longitudinal phacofragmentation. PMID:27621783

Changes in the Diaphragm Lipid Content after Administration of Streptozotocin and High-Fat Diet Regime

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Bartlomiej Lukaszuk

2017-01-01

Full Text Available The diaphragm is a dome-shaped skeletal muscle indispensable for breathing. Its activity contributes up to 70% of the total ventilatory function at rest. In comparison to other skeletal muscles, it is distinguished by an oxidative phenotype and uninterrupted cyclic contraction pattern. Surprisingly, the research regarding diaphragm diabetic phenotype particularly in the light of lipid-induced insulin resistance is virtually nonexistent. Male Wistar rats were randomly allocated into 3 groups: control, streptozotocin-induced (STZ type-1 diabetes, and rodents fed with high-fat diet (HFD. Additionally, half of the animals from each group were administered with myriocin, a robust, selective inhibitor of ceramide synthesis and, therefore, a potent agent ameliorating insulin resistance. Diaphragm lipid contents were evaluated using chromatography. Fatty acid transporter expression was determined by Western blot. The STZ and HFD rats had increased concentration of lipids, namely, ceramides (CER and diacylglycerols (DAG. Interestingly, this coincided with an increased concentration of long-chain (C ≥ 16 saturated fatty acid species present in both the aforementioned lipid fractions. The CER/DAG accumulation was accompanied by an elevated fatty acid transporter expression (FATP-1 in HFD and FATP-4 in STZ. Surprisingly, we observed a significantly decreased triacylglycerol content in the diaphragms of STZ-treated rats.

[Phacoemulsification of subluxated lens with capsular tension ring implantation].

Science.gov (United States)

Dorecka, Mariola; Rokicki, Wojciech; Nita, Malgorzata; Krysik, Katarzyna; Nita, Ewa; Sikorska, Aleksandra; Romaniuk, Wanda

2007-01-01

To evaluate long term results of phacoemulsification with PC IOL and capsular tension ring (CTR) implantation in lens subluxation. The study comprised of 134 patients--146 eyes with subluxated lens. In all cases phacoemulsification with PC IOL and CTR implantation was performed. No intaroperative complications has occured. Postoperative complications included: inflammation in the anterior chamber in 3 eyes (2.1%), retinal detachment in 2 eyes (1.4%). In all cases there was no PC IOL decentration. (1) CTR facilitates phacoemulsification with PC IOL implantation in lens subluxation. (2) Phacoemulsification of subluxated lens with PC IOL and CTR implantation seems to be safe and effective procedure.

Pigment dispersion syndrome associated with spontaneous subluxation of crystalline lens

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Vikas Veerwal

2017-01-01

Full Text Available Pigment dispersion syndrome (PDS is an ocular condition characterized by a dispersion of iris pigment throughout the eye. This pigment is deposited in a characteristic manner on the corneal endothelium as Krukenberg's spindle, anterior surface of the iris, in the trabecular meshwork, on the lens and zonule and occasionally on the anterior hyaloid face. Even with deposition of pigment on zonular fibers, no zonular weakness, or zonular dehiscence has been reported in these cases. We report a unique case of PDS with bilateral spontaneous subluxation of crystalline lens. With characteristic findings of pigment distribution in both his eyes, the patient had concave iris configuration with heavily pigmented trabecular meshwork confirming the diagnosis of PDS. The patient had bilateral 180° temporal subluxation of crystalline lens in both his eyes. The usual cause of lens subluxation such as Marfan's Syndrome and Ehler's Danlos Syndrome was ruled out. The patient underwent right eye followed by left eye intracapsular cataract extraction with ab-interno technique with postoperative best-corrected visual acuity (BCVA of 6/9 in both eyes. Spontaneous subluxation of crystalline lens in isolated PDS is not known to occur and has been reported by means of this case. We recommend a thorough assessment of zonular status in all cases of PDS.

Pigment dispersion syndrome associated with spontaneous subluxation of crystalline lens.

Science.gov (United States)

Veerwal, Vikas; Goyal, Jawahar Lal; Jain, Parul; Arora, Ritu

2017-01-01

Pigment dispersion syndrome (PDS) is an ocular condition characterized by a dispersion of iris pigment throughout the eye. This pigment is deposited in a characteristic manner on the corneal endothelium as Krukenberg's spindle, anterior surface of the iris, in the trabecular meshwork, on the lens and zonule and occasionally on the anterior hyaloid face. Even with deposition of pigment on zonular fibers, no zonular weakness, or zonular dehiscence has been reported in these cases. We report a unique case of PDS with bilateral spontaneous subluxation of crystalline lens. With characteristic findings of pigment distribution in both his eyes, the patient had concave iris configuration with heavily pigmented trabecular meshwork confirming the diagnosis of PDS. The patient had bilateral 180° temporal subluxation of crystalline lens in both his eyes. The usual cause of lens subluxation such as Marfan's Syndrome and Ehler's Danlos Syndrome was ruled out. The patient underwent right eye followed by left eye intracapsular cataract extraction with ab-interno technique with postoperative best-corrected visual acuity (BCVA) of 6/9 in both eyes. Spontaneous subluxation of crystalline lens in isolated PDS is not known to occur and has been reported by means of this case. We recommend a thorough assessment of zonular status in all cases of PDS.

Clinical research on high oxygen permeable contact lens used after photorefractive keratectomy surgery

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Hao-Jiang Yang

2013-07-01

Full Text Available AIM: To evaluate the outcome of high oxygen permeable contact lens used after photorefractive keratectomy(PRKsurgery.METHODS: Totally 95 patients(190 eyesafter PRK were included. Patients were randomly assigned to wear high oxygen permeable contact lens in one eye and normal lens in the fellow eye after surgery. The subjective symptoms and corneal epithelial status after PRK were evaluated. Uncorrected visual acuity(UCVAand haze were assessed at 6 months after PRK.RESULTS: Complaints of blurred vision, pain and photophobia were statistically more among the normal lens group than high oxygen permeable contact lens group(PPP=0.35. There was no difference in UCVA and haze 6 months after surgery(P=0.55. CONCLUSION: High oxygen permeable contact lens can significantly produce less the corneal irritated symptoms, reduce the discomfort feeling and promote healing of corneal epithelium after PRK.

Azacitidine-lenalidomide (ViLen) combination yields a high response rate in higher risk myelodysplastic syndromes (MDS)-ViLen-01 protocol.

Science.gov (United States)

Mittelman, Moshe; Filanovsky, Kalman; Ofran, Yishai; Rosenbaum, Hanna; Raanani, Pia; Braester, Andrei; Goldschmidt, Neta; Kirgner, Ilya; Herishanu, Yair; Perri, Chava; Ellis, Martin; Oster, Howard S

2016-10-01

Azacitidine treatment is effective in higher risk MDS (HR-MDS), with less than 50 % response, lasting 2 years. Aza and lenalidomide (Len) have a potential synergistic effect. ViLen-01 phase IIa trial includes 6-month induction (Aza 75 mg/m(2)/day, days 1-5, Len 10 mg/day, days 6-21, every 28 days), 6-month consolidation (Aza 75 mg/m(2)/day, days 1-5, every 28 days), and 12-month maintenance (Len 10 mg/day, days 1-21, every 28 days). Response was evaluated according to IWG criteria. Totally, 25 patients enrolled, with an average of 76.3 years old (60-87), and 88 % with major comorbidities. Thirteen patients completed induction, 7 proceeded for consolidation, and 2 for maintenance. The overall response rate (ORR) was 72 % (18/25), with 6 (24 %) for CR, 3 (12 %) for marrow CR, and 9 (36 %) for hematologic improvement (HI). The 7 non-responding patients were on the study 3 days to 4.1 months. At 6 months, 4 of 6 evaluable patients achieved complete cytogenetic response and 2 with del (5q) at diagnosis. Adverse events (AEs) were as expected in these patients: grades III-IV, mainly hematologic-thrombocytopenia (20 patients) and neutropenia (13 patients). The common non-hematologic AEs were infections (14 patients), nausea (7), vomiting (7), diarrhea (7), and skin reactions (5). The median progression-free survival (PFS) was 12 ± 1.36 months, with median overall survival (OS) of 12 ± 1.7 months. Quality of life (FACT questionnaire) data were available for 12 patients with a tendency towards improved QoL. This trial with elderly HR-MDS patients with an expected poor prognosis demonstrates a high (72 %) response rate and a reasonable expected safety profile but a relatively short PFS and OS.

Surgical effect of traumatic lens dislocation with secondary glaucoma

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Xiao-Dan Zhang

2014-10-01

Full Text Available AIM: To retrospectively evaluate the effect of lens extraction combined with vitrectomy to treat traumatic lens dislocation with secondary glaucoma.METHODS:Thirty-one eyes(31 casesof lens dislocation caused by blunt trauma with secondary glaucoma were treated respectively with cataract extraction combined with anterior vitrectomy, trabeculectomy and intraocular lens implantation. The visual acuity and pressure were observed 1wk, 1 and 3mo after operative. RESULTS:Thirty-one eyes were all complete the operation successfully, and 6 eyes were given combined trabeculectomy, 9 eyes were implanted anterior chamber intraocular lens implantation(IOLand 15 eyes were given posterior chamber suture fixation. Sixteen eyes were implanted in one-stage operation, while 8 eyes were implanted in two-stage operation. All intraocular pressure(IOPwere controlled to the normal level after operation and 23 eyes had visual acuity of more than 0.3.CONCLUSION:Lens extraction combined with vitrectomy is an effective method for treatment of lens dislocation with secondary glaucoma. In order to control the IOP and get well visual function, we should choose IOL implantation or trabeculectomy according to the patient's condition.

Microscopic analysis of an opacified OFT CRYL® hydrophilic acrylic intraocular lens

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Bruna Vieira Ventura

Full Text Available ABSTRACT A 51-year-old patient underwent posterior vitrectomy with perfluoropropane gas injection, phacoemulsification, and implantation of an Oft Cryl® hydrophilic acrylic intraocular lens (IOL because of traumatic retinal detachment and cataract in the right eye. On the first postoperative day, gas was filling the anterior chamber because of patient's non-compliance in terms of head positioning, and was reabsorbed within one week. Eight months later, the patient returned complaining of a significant decrease in vision. IOL opacification was noticed by slit-lamp examination. The lens was explanted to undergo gross and light microscopic analysis. The lens was also stained with the alizarin red method for calcium identification. Light microscopic analysis confirmed the presence of granular deposits, densely distributed in an overall circular pattern in the central part of the lens optic. The granules stained positive for calcium. This is the first case of the opacification of this type of hydrophilic lens. Surgeons should be aware of this potential postoperative complication, and the use of hydrophilic IOLs should be avoided in procedures involving intracameral gas because of the risk of IOL opacification.

Development of diaphragm automatic homing equipment

International Nuclear Information System (INIS)

Kobayashi, Hidetoshi; Yamada, Koji; Moriya, Shinichi; Koike, Jiro; Okabe, Masao; Oyama, Akihiro.

1996-01-01

In steam-turbine overhaul inspection, one of the most important processes is to remove rust and deposited contaminants on the surface of turbine parts, while the turbine is in operation, to recover thermal efficiency and prepare good surface conditions for color penetrant inspection. These processes generally are done by dry honing, but this generates dust. To protect laborers against these conditions, Hitachi, Ltd. has developed automatic honing equipment for the diaphragms of the nuclear steam turbine. This equipment was first used in the first annual inspection and overhaul of Hamaoka Nuclear Power Plant No.4 of Chubu Electric Power Inc. (author)

Three-Dimensional Cataract Crystalline Lens Imaging With Swept-Source Optical Coherence Tomography.

Science.gov (United States)

de Castro, Alberto; Benito, Antonio; Manzanera, Silvestre; Mompeán, Juan; Cañizares, Belén; Martínez, David; Marín, Jose María; Grulkowski, Ireneusz; Artal, Pablo

2018-02-01

To image, describe, and characterize different features visible in the crystalline lens of older adults with and without cataract when imaged three-dimensionally with a swept-source optical coherence tomography (SS-OCT) system. We used a new SS-OCT laboratory prototype designed to enhance the visualization of the crystalline lens and imaged the entire anterior segment of both eyes in two groups of participants: patients scheduled to undergo cataract surgery, n = 17, age range 36 to 91 years old, and volunteers without visual complains, n = 14, age range 20 to 81 years old. Pre-cataract surgery patients were also clinically graded according to the Lens Opacification Classification System III. The three-dimensional location and shape of the visible opacities were compared with the clinical grading. Hypo- and hyperreflective features were visible in the lens of all pre-cataract surgery patients and in some of the older adults in the volunteer group. When the clinical examination revealed cortical or subcapsular cataracts, hyperreflective features were visible either in the cortex parallel to the surfaces of the lens or in the posterior pole. Other type of opacities that appeared as hyporeflective localized features were identified in the cortex of the lens. The OCT signal in the nucleus of the crystalline lens correlated with the nuclear cataract clinical grade. A dedicated OCT is a useful tool to study in vivo the subtle opacities in the cataractous crystalline lens, revealing its position and size three-dimensionally. The use of these images allows obtaining more detailed information on the age-related changes leading to cataract.

Effect of chronic smoking on lens nucleus as assessed by Pentacam HR lens densitometry in young adults.

Science.gov (United States)

Pekel, Gökhan; Cetin, Ebru Nevin; Acer, Semra; Yagci, Ramazan; Altintas, Seher; Ongun, Gülin Tugba

2014-06-01

To evaluate the effects of chronic tobacco smoking on lens nucleus by Pentacam HR lens densitometry (LD) in young adults. Prospective cross-sectional case series. Thirty subjects (23 M, 7 F) who were chronic cigarette smokers (≥10 cigarettes/day for at least 2 years) (group 1) and another 30 subjects (23 M, 7 F) who did not smoke (group 2), were included in this study. The patients were matched for age and sex between the groups. The exclusion criteria were any history of ocular surgery, any systemic disorders and any ocular diseases except for mild refractive disorders. Lens densitometry measurements were done with the Pentacam HR (Oculus, Wetzlar, Germany). The Schirmer test and pachymetry measurements were also performed. Mean age of the patients for both groups was 28.90 ± 8.20 years (range: 18-40 years). Mean lens densitometry (LD) measurements of Group 1 (chronic cigarette smoking group) were higher than those of Group 2 (control group) in all LD techniques; however only mean "peak" LD measurements showed a statistically significant difference between these two groups (Group 1: 8.67 ± 0.61, Group 2: 8.44 ± 0.70, p = 0.04). The mean Schirmer test value was 12.43 ± 5.60 mm in Group 1 and 13.00 ± 4.26 mm in Group 2 (p = 0.55). The mean central corneal thickness (CCT) value was 564.23 ± 34.61 µm in Group 1 and 550.47 ± 32.94 µm in Group 2 (p = 0.03). The Pentacam HR LD seems to be an important option for the evaluation of lens nucleus in young adults, because it gives objective and quantitative data. Although chronic smoking increases lens nucleus density in young adults, the effect is not statistically significant when compared with the control group.

Secondary Angle Closure due to Crystalline Lens Dislocation in a Patient with Atopic Dermatitis and Chronic Eye Rubbing

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Justin Kuiper

2018-03-01

Full Text Available Purpose: To report an unusual case of ectopia lentis and angle closure in a patient with chronic eye rubbing. Methods: A 57-year-old male with a history of poorly controlled atopic dermatitis presented with right eye pain, decreased vision, and an intraocular pressure (IOP of 55 mm Hg. He had no past history of ocular disease and no reported history of trauma. He did report a history of chronic eye rubbing. Results: Best corrected visual acuity was hand motions. The examination revealed severe atopic keratoconjunctivitis in both eyes, microcystic corneal edema of the right eye, and 2+ nuclear sclerosis in both eyes. Gonioscopy showed no visible angle structures OD and an open angle OS. Topical and oral IOP-lowering medications and a laser iridotomy were unsuccessful at lowering IOP. He was taken to the operating room for a lensectomy and was found to have 9 clock hours of zonular dehiscence and a dislocated lens. After lensectomy, the IOP improved to 9 mm Hg on postoperative day 1. A follow-up examination at 2 weeks showed improved acuity to 20/150 with a pinhole and an IOP of 10 mm Hg. A dilated examination OS did not reveal significant phacodonesis, and the patient was referred for a possible sutured sulcus lens or anterior chamber intraocular lens. Conclusions: It is important for the provider to consider ectopia lentis in the differential for patients with pupillary block angle closure. For patients with atopic disease, one should be aware that eye rubbing may be a cause of zonular dehiscence, even in the absence of reported trauma or prior intraocular surgery.

Analysis of phakic before intraocular lens implantation for fundus examination

OpenAIRE

Juan Chen; Zhong-Ping Chen; Rui-Ling Zhu

2014-01-01

AIM:To investigate the findings of the eyes which were examined preoperatively by three mirror contact lens before the implantation of implantable collamer lens(ICL). To analysis the retinal pathological changes and to explore the clinical analysis of early diagnosis and treatment in retinopathy on fundus examination before operation. METHODS:The retrospective case series study included 127 eyes of 64 patients who underwent phakic intraocular lens implantation were received the fundus examina...

Aviation Fuel Gauging Sensor Utilizing Multiple Diaphragm Sensors Incorporating Polymer Optical Fiber Bragg Gratings

DEFF Research Database (Denmark)

Marques, C. A. F.; Pospori, A.; Saez-Rodriguez, D.

2016-01-01

A high-performance fuel gauging sensor is described that uses five diaphragm-based pressure sensors, which are monitored using a linear array of polymer optical fiber Bragg gratings. The sensors were initially characterized using water, revealing a sensitivity of 98 pm/cm for four of the sensors...... of sensors manufactured with a polyurethane-based diaphragm showed no measurable deterioration over a three month period immersed in fuel. These sensors exhibited a sensitivity of 39 pm/cm, which is less than the silicone rubber devices due to the stiffer nature of the polyurethane material used....

Anterior Lens Capsule and Iris Thicknesses in Pseudoexfoliation Syndrome.

Science.gov (United States)

Batur, Muhammed; Seven, Erbil; Tekin, Serek; Yasar, Tekin

2017-11-01

The aim of this study was to evaluate anatomic properties of the lens capsule and iris by anterior segment optical coherence tomography (AS-OCT) in patients with pseudoexfoliation (PEX). This prospective study included 62 eyes of 62 patients with PEX syndrome and 43 eyes of 43 age- and gender-matched controls. All subjects underwent full ophthalmologic examinations including AS-OCT. Pupillary diameter, midperipheral stromal iris thickness, central and temporal lens capsule thicknesses, and peripheral pseudoexfoliation material thickness on the anterior lens capsule surface were measured and recorded. Mean age was 66.8 ± 9.3 years in the PEX group and 65.5 ± 8.9 years in the control group (p = 0.44). The PEX group consisted of 62 patients: 38 men (61.3%) and 24 women (38.7%); the control group included 43 subjects: 25 men (58.1%) and 18 women (41.9%). Pupillary diameter after pharmacologic mydriasis was 21% smaller in the PEX group than controls. Mean midperipheral iris thickness was 36 ± 7.2 μm (7.8%) thinner in the PEX group than that of control group (p = 0.047). The central anterior capsule was a mean of 3.40 ± 0.51 μm (18%) thicker in the PEX group compared to the control group (p = 0.0001). The temporal anterior lens capsule was a mean of 0.17 ± 0.15 μm thicker in the PEX group compared to the control group (p = 0.81). With high-resolution OCT imaging, it has become possible to evaluate the anterior lens capsule without histologic examination and demonstrate that it is thicker than normal in PEX patients.

Potential for Revitalisation of the Diaphragm for Family Planning in ...

African Journals Online (AJOL)

AJRH Managing Editor

diaphragm, into the existing family planning method mix in Uganda. A total of 26 ... expand women's options for contraceptive protection. ... several countries, and the product was approved in ..... younger clients and may not adequately market ... different stages of their life cycle. .... maternal mortality ratio in Uganda: priority.

Acanthamoeba keratitis in Scotland: risk factors for contact lens wearers.

Science.gov (United States)

Seal, D V; Kirkness, C M; Bennett, H G; Peterson, M

1999-01-01

To investigate risk factors for Acanthamoeba keratitis amongst contact lens wearers in Scotland. Patients with Acanthamoeba keratitis in the Scottish study, all of whom wore contact lenses, were compared with 46 healthy asymptomatic contact lens-wearing controls. They were all visited at home for contact lens and environmental microbiological sampling. In addition, all 288 optical practices in the West of Scotland were polled for contact lens types and disinfecting solutions sold in 1995, and a sample, each of whom fitted more than 500 contact lenses per year, were polled for a second time. Independently, a poll was commissioned by the Eyecare Information Service in July/August 1995 to estimate the numbers of contact lens wearers in Scotland and the UK. Industry was polled for numbers of each contact lens disinfecting regimen sold in Scotland in 1995. West of Scotland, UK. All contact lens wearers among the 3 million population of the West of Scotland Health Board Areas. Risk factors for Acanthamoeba infection and recommendations for its prevention. When Acanthamoeba infection occurred, patients' home water systems were frequently (54%) found to be colonised by this amoeba. Patients more frequently washed their storage cases in tap water than controls (Pmethods (chlorine tablets or no disinfection). However further investigation showed that these methods were associated with an increased probability of rinsing the storage case in tap water, so that these two behaviours are confounded in the group studied. Failure to disinfect contact lenses, non-compliant use of chlorine tablets and/or introduction of tap water rinsing of storage cases were associated with increased risk of Acanthamoeba infection. New multipurpose solutions and hydrogen peroxide gave the lowest risk of Acanthamoeba infection, with no statistically significant difference between them. Ionic high-water content (FDA group 4) contact lenses were at increased risk of being associated with Acanthamoeba

Effect of aspherical and yellow tinted intraocular lens on blue-on-yellow perimetry

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Rodrigo França de Espíndola

2012-10-01

Full Text Available PURPOSE: To investigate the possible effect of aspherical or yellow tinted intraocular lens (IOL on contrast sensitivity and blue-on-yellow perimetry. METHODS: This prospective randomized bilateral double-masked clinical study included 52 patients with visually significant bilateral cataracts divided in two groups; 25 patients (50 eyes received aspherical intraocular lens in one eye and spherical intraocular lens in the fellow eye; and 27 patients (54 eyes received ultraviolet and blue light filter (yellow tinted IOL implantation in one eye and acrylic ultraviolet filter IOL in the fellow eye. The primary outcome measures were contrast sensitivity and blue-on-yellow perimetry values (mean deviation [MD] and pattern standard deviation [PSD] investigated two years after surgery. The results were compared intra-individually. RESULTS: There was a statistically significant between-group (aspherical and spherical intraocular lens difference in contrast sensitivity under photopic conditions at 12 cycles per degree and under mesopic conditions at all spatial frequencies. There were no between-group significant differences (yellow tinted and clear intraocular lens under photopic or mesopic conditions. There was no statistically significant difference between all intraocular lens in MD or PSD. CONCLUSION: Contrast sensitivity was better under mesopic conditions with aspherical intraocular lens. Blue-on-yellow perimetry did not appear to be affected by aspherical or yellow tinted intraocular lens. Further studies with a larger sample should be carried out to confirm or not that hypotheses.

Disinfection capacity of PuriLens contact lens cleaning unit against Acanthamoeba.

Science.gov (United States)

Hwang, Thomas S; Hyon, Joon Young; Song, Jae Kyung; Reviglio, Victor E; Spahr, Harry T; O'Brien, Terrence P

2004-01-01

The PuriLens contact lens system is indicated for cleaning and disinfection of soft (hydrophilic) contact lenses by means of subsonic agitation to remove lens deposits and microorganisms, and ultraviolet irradiation of the storage solution for disinfection. The capacity of the PuriLens system to disinfect storage solutions contaminated with known concentrations of Staphylococcus aureus, Pseudomonas aeruginosa, and Acanthamoeba species was evaluated. An in vitro assessment of the antibacterial and antiparasitic efficacy of the PuriLens system was performed. Separated batches of the storage solution for the cleansing system were contaminated with stock strains of S. aureus and P. aeruginosa. A comparison of the microbiologic content was made between the solution before and after the cycle. The PuriLens system effectively eradicated S. aureus and P. aeruginosa organisms after a 15-minute cycle. However, viable cysts of acanthamoeba were recovered in the solution after the 15-minute cycle. The PuriLens system is highly efficient in protecting against contamination with common bacterial ocular pathogens. Acanthamoeba cysts, however, can survive in the solution or contact lens bath undergoing integrated subsonic debridement and indirect ultraviolet light disinfection. Use of chemical disinfecting solutions that contain agents such as chlorhexidine or other cationic antiseptics may be advisable in conjunction with use of the PuriLens device, especially in high-risk settings.

Can the accuracy of multifocal intraocular lens power calculation be improved to make patients spectacle free?

Science.gov (United States)

Ramji, Hasnain; Moore, Johnny; Moore, C B Tara; Shah, Sunil

2016-04-01

To optimise intraocular lens (IOL) power calculation techniques for a segmental multifocal IOL, LENTIS™ MPlus(®) (Oculentis GmbH, Berlin, Germany) and assess outcomes. A retrospective consecutive non-randomised case series of patients receiving the MPlus(®) IOL following cataract surgery or clear lens extraction was performed at a privately owned ophthalmic hospital, Midland Eye, Solihull, UK. Analysis was undertaken of 116 eyes, with uncomplicated lens replacement surgery using the LENTIS™ MPlus(®) lenses. Pre-operative biometry data were stratified into short (<22.00 mm) and long axial lengths (ALs) (≥22.00 mm). IOL power predictions were calculated with SRK/T, Holladay I, Hoffer Q, Holladay II and Haigis formulae and compared to the final manifest refraction. These were compared with the OKULIX ray tracing method and the stratification technique suggested by the Royal College of Ophthalmologists (RCOphth). Using SRK/T for long eyes and Hoffer Q for short eyes, 64% achieved postoperative subjective refractions of ≤±0.25 D, 83%≤±0.50 D and 93%≤±0.75 D, with a maximum predictive error of 1.25D. No specific calculation method performed best across all ALs; however for ALs under 22 mm Hoffer Q and Holliday I methods performed best. Excellent but equivalent overall refractive results were found between all biometry methods used in this multifocal IOL study. For eyes with ALs under 22 mm Hoffer Q and Holliday I performed best. Current techniques mean that patients are still likely to need top up glasses for certain situations. Copyright © 2015 Elsevier Ltd. All rights reserved.

Refractive lens exchange in younger and older presbyopes: comparison of complication rates, 3 months clinical and patient-reported outcomes

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Schallhorn SC

2017-08-01

Full Text Available Steven C Schallhorn,1–3 Julie M Schallhorn,1 Martina Pelouskova,3 Jan A Venter,3 Keith A Hettinger,3 Stephen J Hannan,3 David Teenan3 1Department of Ophthalmology, University of California, San Francisco, CA, USA; 2Roski Eye Institute, University of Southern California, Los Angeles, CA, USA; 3Optical Express, Glasgow UK Purpose: To compare refractive and visual outcomes, patient satisfaction, and complication rates among different age categories of patients who underwent refractive lens exchange (RLE. Methods: A stratified, simple random sample of patients matched on preoperative sphere and cylinder was selected for four age categories: 45–49 years (group A, 50–54 years (group B, 55–59 years (group C, and 60–65 years (group D. Each group contained 320 patients. All patients underwent RLE with a multifocal intraocular lens at least in one eye. Three months postoperative refractive/visual and patient-reported outcomes are presented. Results: The percentage of patients that achieved binocular uncorrected distance visual acuity 20/20 or better was 91.6% (group A, 93.8% (group B, 91.6% (group C, 88.8% (group D, P=0.16. Binocularly, 80.0% of patients in group A, 84.7% in group B, 78.9% in group C, and 77.8% in group D achieved 20/30 or better uncorrected near visual acuity (P=0.13. The proportion of eyes within 0.50 D of emmetropia was 84.4% in group A, 86.8% in group B, 85.7% in group C, and 85.8% in group D (P=0.67. There was no statistically significant difference in postoperative satisfaction, visual phenomena, dry eye symptoms, distance or near vision activities. Apart from higher rate of iritis in the age group 50–55 years, there was no statistically significant difference in postoperative complication rates. Conclusion: RLE can be safely performed in younger as well as older presbyopes. No significant difference was found in clinical or patient-reported outcomes. Keywords: refractive lens exchange, multifocal IOLs, younger

CONSTRUCTIVE ASPECTS INFLUENCE ON STIFFNESS OF DIAPHRAGM WALLS IN FRAME CONSTRUCTIONS WITH (LIGHT STEEL THIN –WALLED STRUCTURES

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M. V. Savytskyi

2010-10-01

Full Text Available The dependences of influence of structural features of diaphragms of lightweight steel framing braced wall structures on their stiffness are determined. On the basis of dependences the procedure for estimation of stiffness of a diaphragm of any configuration that allows making decisions for maintenance of building stiffness is developed.

Measurement of Crystalline Lens Volume During Accommodation in a Lens Stretcher.

Science.gov (United States)

Marussich, Lauren; Manns, Fabrice; Nankivil, Derek; Maceo Heilman, Bianca; Yao, Yue; Arrieta-Quintero, Esdras; Ho, Arthur; Augusteyn, Robert; Parel, Jean-Marie

2015-07-01

To determine if the lens volume changes during accommodation. The study used data acquired on 36 cynomolgus monkey lenses that were stretched in a stepwise fashion to simulate disaccommodation. At each step, stretching force and dioptric power were measured and a cross-sectional image of the lens was acquired using an optical coherence tomography system. Images were corrected for refractive distortions and lens volume was calculated assuming rotational symmetry. The average change in lens volume was calculated and the relation between volume change and power change, and between volume change and stretching force, were quantified. Linear regressions of volume-power and volume-force plots were calculated. The mean (± SD) volume in the unstretched (accommodated) state was 97 ± 8 mm3. On average, there was a small but statistically significant (P = 0.002) increase in measured lens volume with stretching. The mean change in lens volume was +0.8 ± 1.3 mm3. The mean volume-power and volume-load slopes were -0.018 ± 0.058 mm3/D and +0.16 ± 0.40 mm3/g. Lens volume remains effectively constant during accommodation, with changes that are less than 1% on average. This result supports a hypothesis that the change in lens shape with accommodation is accompanied by a redistribution of tissue within the capsular bag without significant compression of the lens contents or fluid exchange through the capsule.

Mechanical characterization of the mouse diaphragm with optical coherence elastography reveals fibrosis-related change of direction-dependent muscle tissue stiffness

Science.gov (United States)

Wang, Shang; Loehr, James A.; Larina, Irina V.; Rodney, George G.; Larin, Kirill V.

2016-03-01

The diaphragm, composed of skeletal muscle, plays an important role in respiration through its dynamic contraction. Genetic and molecular studies of the biomechanics of mouse diaphragm can provide great insights into an improved understanding and potential treatment of the disorders that lead to diaphragm dysfunction (i.e. muscular dystrophy). However, due to the small tissue size, mechanical assessment of mouse diaphragm tissue under its proper physiological conditions has been challenging. Here, we present the application of noncontact optical coherence elastography (OCE) for quantitative elastic characterization of ex vivo mouse diaphragm. Phase-sensitive optical coherence tomography was combined with a focused air-puff system to capture and measure the elastic wave propagation from tissue surface. Experiments were performed on wildtype and dystrophic mouse diaphragm tissues containing different levels of fibrosis. The OCE measurements of elastic wave propagation were conducted along both the longitudinal and transverse axis of the muscle fibers. Cross-correlation of the temporal displacement profiles from different spatial locations was utilized to obtain the propagation time delay, which was used to calculate the wave group velocity and to further quantify the tissue Young's modulus. Prior to and after OCE assessment, peak tetanic force was measured to monitor viability of the tissue during the elasticity measurements. Our experimental results indicate a positive correlation between fibrosis level and tissue stiffness, suggesting this elastic-wave-based OCE method could be a useful tool to monitor mechanical properties of skeletal muscle under physiological and pathological conditions.

Potential for Revitalisation of the Diaphragm for Family Planning in ...

African Journals Online (AJOL)

This health systems assessment evaluated the feasibility of introducing a new contraceptive device, the SILCS single-size diaphragm, into the existing family planning method mix in Uganda. A total of 26 focus group discussions with 201 female and 77 male potential users and 98 key informant interviews with policymakers ...

Advanced performance of small diaphragm vacuum pumps through the use of mechatronics

Science.gov (United States)

Lachenmann, R.; Dirscherl, J.

Oil-free diaphragm vacuum pumps have proven to be the best way in vacuum generation for the chemical laboratory and they also find increasing use as backing pumps for modern wide-range turbo molecular pumps. The majority of vacuum pumps in practical use pump only a rather small percentage of their lifetime at full gas load. A pump backing a turbo molecular pump does not have to pump a significant gas load when the high-vacuum pump is running at ultimate vacuum pressure. Also, for a vacuum distillation the vacuum pump has to operate at full speed only at the beginning to lower the pressure inside the system to a vacuum level where evaporation starts. In a rather leak-tight system the distillation process continues by evaporating from the hot liquid and condensing at the cold condenser without the need of a mechanical vacuum pump. Rotational speed controlled diaphragm pumps are now available through progress in mechatronics and offer high pumping speed capability for fast pump-down cycles and precise pressure control for distillations. At low gas load the rotational speed can be reduced, improving maintenance intervals, power consumption, noise, vibration and - surprisingly - also ultimate pressure. The different behaviour in pumping speed and ultimate pressure of rotational speed controlled diaphragm pumps in comparison to constant-speed pumps is related to the mechanical properties of the valves and gas dynamics .

High temperature energy harvesters utilizing ALN/3C-SiC composite diaphragms

Science.gov (United States)

Lai, Yun-Ju; Li, Wei-Chang; Felmetsger, Valery V.; Senesky, Debbie G.; Pisano, Albert P.

2014-06-01

Microelectromechanical systems (MEMS) energy harvesting devices aiming at powering wireless sensor systems for structural health monitoring in harsh environments are presented. For harsh environment wireless sensor systems, sensor modules are required to operate at elevated temperatures (> 250°C) with capabilities to resist harsh chemical conditions, thereby the use of battery-based power sources becomes challenging and not economically efficient if considering the required maintenance efforts. To address this issue, energy harvesting technology is proposed to replace batteries and provide a sustainable power source for the sensor systems towards autonomous harsh environment wireless sensor networks. In particular, this work demonstrates a micromachined aluminum nitride/cubic silicon carbide (AlN/3C-SiC) composite diaphragm energy harvester, which enables high temperature energy harvesting from ambient pulsed pressure sources. The fabricated device yields an output power density of 87 μW/cm2 under 1.48-psi pressure pulses at 1 kHz while connected to a 14.6-kΩ load resistor. The effects of pulse profile on output voltage have been studied, showing that the output voltage can be maximized by optimizing the diaphragm resonance frequency based on specific pulse characteristics. In addition, temperature dependence of the diaphragm resonance frequency over the range of 20°C to 600°C has been investigated and the device operation at temperatures as high as 600°C has been verified.

Customer loyalty among daily disposable contact lens wearers.

Science.gov (United States)

Patel, Neelam I; Naroo, Shehzad A; Eperjesi, Frank; Rumney, Nicholas J

2015-02-01

Optometric practices offer contact lenses as cash sale items or as part of monthly payment plans. With the contact lens market becoming increasingly competitive, patients are opting to purchase lenses from supermarkets and Internet suppliers. Monthly payment plans are often implemented to improve loyalty. This study aimed to compare behavioural loyalty between monthly payment plan members and non-members. BBR Optometry Ltd offers a monthly payment plan (Eyelife™) to their contact lens wearers. A retrospective audit of 38 Eyelife™ members (mean±SD: 42.7±15.0 years) and 30 non-members (mean±SD: 40.8±16.7 years) was conducted. Revenue and profits generated, service uptake and product sales between the two groups were compared over a fixed period of 18 months. Eyelife™ members generated significantly higher professional fee revenue (Ployalty among contact lens wearers, particularly service uptake and volume of lens purchases. Additionally the greater professional fees generated, render monthly payment plans an attractive business model and practice builder. Copyright © 2014 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Spectral analysis and comparison of mineral deposits forming in opacified intraocular lens and senile cataractous lens

Science.gov (United States)

Lin, Shan-Yang; Chen, Ko-Hwa; Lin, Chih-Cheng; Cheng, Wen-Ting; Li, Mei-Jane

2010-10-01

This preliminary report was attempted to compare the chemical components of mineral deposits on the surfaces of an opacified intraocular lens (IOL) and a calcified senile cataractous lens (SCL) by vibrational spectral diagnosis. An opacified intraocular lens (IOL) was obtained from a 65-year-old male patient who had a significant decrease in visual acuity 2-years after an ocular IOL implantation. Another SCL with grayish white calcified plaque on the subcapsular cortex was isolated from a 79-year-old male patient with complicated cataract after cataract surgery. Optical light microscope was used to observe both samples and gross pictures were taken. Fourier transform infrared (FT-IR) and Raman microspectroscopic techniques were employed to analyze the calcified deposits. The curve-fitting algorithm using the Gaussian function was also used to quantitatively estimate the chemical components in each deposit. The preliminary results of spectral diagnosis indicate that the opacified IOL mainly consisted of the poorly crystalline, immature non-stoichiometric hydroxyapatite (HA) with higher content of type B carbonated apatites. However, the calcified plaque deposited on the SCL was comprised of a mature crystalline stoichiometric HA having higher contents of type A and type B carbonate apatites. More case studies should be examined in future.

Investigation of geometric design in piezoelectric microelectromechanical systems diaphragms for ultrasonic energy harvesting

Science.gov (United States)

Shi, Qiongfeng; Wang, Tao; Kobayashi, Takeshi; Lee, Chengkuo

2016-05-01

Acoustic energy transfer (AET) has been widely used for contactless energy delivery to implantable devices. However, most of the energy harvesters (ultrasonic receivers) for AET are macro-scale transducers with large volume and limited operation bandwidth. Here, we propose and investigate two microelectromechanical systems diaphragm based piezoelectric ultrasonic energy harvesters (PUEHs) as an alternative for AET. The proposed PUEHs consist of micro-scale diaphragm array with different geometric parameter design. Diaphragms in PUEH-1 have large length to width ratio to achieve broadband property, while its energy harvesting performance is compromised. Diaphragms in PUEH-2 have smaller length to width ratio and thinner thickness to achieve both broadband property and good energy harvesting performance. Both PUEHs have miniaturized size and wide operation bandwidth that are ideally suitable to be integrated as power source for implantable biomedical devices. PUEH-1 has a merged -6 dB bandwidth of 74.5% with a central frequency of 350 kHz. PUEH-2 has two separate -6 dB bandwidth of 73.7%/30.8% with central frequencies of 285 kHz/650 kHz. They can adapt to various ultrasonic sources with different working frequency spectrum. Maximum output power is 34.3 nW and 84.3 nW for PUEH-1 and PUEH-2 at 1 mW/cm2 ultrasound intensity input, respectively. The associated power density is 0.734 μW/cm2 and 4.1 μW/cm2, respectively. Better energy harvesting performance is achieved for PUEH-2 because of the optimized length to width ratio and thickness design. Both PUEHs offer more alignment flexibility with more than 40% power when they are in the range of the ultrasound transmitter.

Resultados topográficos en pacientes portadores de lentes de contacto Topographic results achieved patients wearing contact lens

Directory of Open Access Journals (Sweden)

Tania Aymeé Díaz Martínez

2009-06-01

results achieved in patients wearing contact lens, who were candidates to refractive surgery with Excimer laser at "Carlos J. Finlay" hospital; to determine the behaviour according to age and sex; to find out the type of contact lens used and the length of wear; and to identify the relationship of the induced corneal topographic pattern in contact lens wearers with corneal warpage and ketatoconus. METHODS: A retrospective study of the corneal topography of candidates to refractive surgery in the last 2 years was performed in 80 patients (contact lens wearers. OPTIKON AMF510P and HUMPHREY topographers were the instruments to screen the patients. All of them were performed a complete ophthalmological exam (manifest refraction, biomicroscopy, keratometry, pachymetry and corneal topography. Results and their stability were compared. Also age, sex, type of lenses and length of wear were analyzed. RESULTS: One hundred and fifty eight eyes were treated, 83 of them presented with normal topographic pattern whereas 58 had contact lens-induced corneal warpage and 17 suffered keratoconus. The average age of patients was 27 years. Mean corneal astigmatism in patients with keratoconus was -3.25 D and in patients with corneal warpage -1.12 D. The reading of the most even meridian in patients with keratocomus was 46,75 dioptries and with corneal warpage was 43,25 D. As to keratoconus, the most curved meridian reading was 54,75 dioptres and in corneal warpage was 46 dioptres. CONCLUSIONS: The type of contact lens and the length of wear has an effect on the occurrence of induced corneal warpage and subclinical keratoconus, and both recorded a similar topographic pattern.

Anatomy of pudendal nerve at urogenital diaphragm--new critical site for nerve entrapment.

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Hruby, Stephan; Ebmer, Johannes; Dellon, A Lee; Aszmann, Oskar C

2005-11-01

To investigate the relations of the pudendal nerve in this complex anatomic region and determine possible entrapment sites that are accessible for surgical decompression. Entrapment neuropathies of the pudendal nerve are an uncommon and, therefore, often overlooked or misdiagnosed clinical entity. The detailed relations of this nerve as it exits the pelvis through the urogenital diaphragm and enters the mobile part of the penis have not yet been studied. Detailed anatomic dissections were performed in 10 formalin preserved hemipelves under 3.5x loupe magnification. The pudendal nerve was dissected from the entrance into the Alcock canal to the dorsum of the penis. The branching pattern of the nerve and its topographic relationship were recorded and photographs taken. The anatomic dissections revealed that the pudendal nerve passes through a tight osteofibrotic canal just distal to the urogenital diaphragm at the entrance to the base of the penis. This canal is, in part, formed by the inferior ramus of the pubic bone, the suspensory ligament of the penis, and the ischiocavernous body. In two specimens, a fusiform pseudoneuromatous thickening was found. The pudendal nerve is susceptible to compression at the passage from the Alcock canal to the dorsum of the penis. Individuals exposed to repetitive mechanical irritation in this region are especially endangered. Diabetic patients with peripheral neuropathy can have additional compression neuropathy with decreased penile sensibility and will benefit from decompression of the pudendal nerve.

Comparative analysis of the nuclear lens opalescence by the Lens Opacities Classification System III with nuclear density values provided by Oculus Pentacam: a cross-section study using Pentacam Nucleus Staging software.

Science.gov (United States)

Magalhães, Fernanda Pedreira; Costa, Elaine Fiod; Cariello, Angelino Júlio; Rodrigues, Eduardo Buchele; Hofling-Lima, Ana Luisa

2011-01-01

To compare the clinical classification of cataract using the Lens Opacities Classification System (LOCS) III with the mean values of lens density provided by the Pentacam Scheimpflug System in nuclear cataracts. One hundred and one eyes from 101 patients with age-related nuclear cataract were submitted to clinical examination for lens grading score using LOCS III. According to LOCS III, nuclear opalescence was divided in six groups. Patients were evaluated by the Pentacam Scheimpflug System for the mean lens density using the Pentacam lens densitometry program (PLDP), the Pentacam Nucleus Staging (PNS) mean value and the PNS cataract grading score. A positive correlation between the mean values of lens density and LOCS III classification, considering groups 1 to 5, could be noticed with PLDP and PNS mean value. The mean values between the groups were similar using the PLDP and the PNS mean value. However, when the PNS cataract grading score was evaluated, there was low correspondence with LOCS III classification. Pentacam Scheimpflug device offers an objective measure of the lens nuclear density on nuclear cataracts. PLDP and the PNS mean value were both useful to evaluate age-related nuclear cataract up to LOCS III group 5.

AutoLens: Automated Modeling of a Strong Lens's Light, Mass and Source

Science.gov (United States)

Nightingale, J. W.; Dye, S.; Massey, Richard J.

2018-05-01

This work presents AutoLens, the first entirely automated modeling suite for the analysis of galaxy-scale strong gravitational lenses. AutoLens simultaneously models the lens galaxy's light and mass whilst reconstructing the extended source galaxy on an adaptive pixel-grid. The method's approach to source-plane discretization is amorphous, adapting its clustering and regularization to the intrinsic properties of the lensed source. The lens's light is fitted using a superposition of Sersic functions, allowing AutoLens to cleanly deblend its light from the source. Single component mass models representing the lens's total mass density profile are demonstrated, which in conjunction with light modeling can detect central images using a centrally cored profile. Decomposed mass modeling is also shown, which can fully decouple a lens's light and dark matter and determine whether the two component are geometrically aligned. The complexity of the light and mass models are automatically chosen via Bayesian model comparison. These steps form AutoLens's automated analysis pipeline, such that all results in this work are generated without any user-intervention. This is rigorously tested on a large suite of simulated images, assessing its performance on a broad range of lens profiles, source morphologies and lensing geometries. The method's performance is excellent, with accurate light, mass and source profiles inferred for data sets representative of both existing Hubble imaging and future Euclid wide-field observations.

Visual outcome with the Oculentis Mplus intraocular lens

OpenAIRE

Si-Yuan Liu; Xu Yang

2017-01-01

AIM: To evaluate the visual outcome of Oculentis Mplus intraocular lens(IOL).METHODS: Totally 20 eyes in 20 patients received phacoemulsification and Oculentis Mplus intraocular lens implantation were as test group, and 20 eyes(Aspira-aA IOL)were as control group. The following postoperative examinations were performed after operation for 3mo: uncorrected visual acuity of distance and near, refractive results, UBM examination, the rate of wearing spectacles and the complications. RESULTS: At ...

Analysis of causes of intraocular lens explantations in the material of Department of Ophthalmology, Medical University of Lodz.

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Wilczyński, Michał; Wilczyńska, Olena; Omulecki, Wojciech

2009-01-01

Implantation of intraocular lenses (IOLS) has become a standard practice in cataract surgery, however, similar to any other type of surgery, using IOLs is not complication-free and sometimes explantation of intraocular lenses may be necessary. This study was to gather data and analyze causes of intraocular lens explantations, performed in the Department of Ophthalmology, Medical University of Łódź. The data were gathered from medical documentation of all patients who underwent intraocular lens removal from January 2003 to July 2006. The examined group consisted of 16 patients (16 eyes): 9 women (fraction 0.56), and 7 men (fraction 0.44), at the age from 21 to 82 years (mean age 62.4 years, SD +/- 15.5). In all patients IOL explantation was performed under local, peribulbar anaesthesia. Two groups of patients were distinguished: patients who had an anterior chamber lens explanted (3 patients, fraction 0.19) and patients who underwent posterior chamber lens explantation (13 patients, fraction 0.81). Causes of AC IOL explantations were: vaulting of the IOL (1 eye, fraction 0.06), luxation of the IOL to the vitreous cavity (1 eye, fraction 0.06), and painful eyeball after anterior chamber lens implantation (1 eye, fraction 0.06). Causes of PC IOL explantations were: subluxation of the IOL (6 eyes, fraction 0.38), luxation of the lens to the vitreous cavity (3 eyes, fraction 0.19), luxation of the lens to the anterior chamber (1 eye, fraction 0.06), endophthalmitis (2 eyes, fraction 0.13) and incorrect lens power (1 eye, fraction 0.06). In the majority of eyes (n = 13, fraction 0.81) the removed implant was replaced by another intraocular lens, but 3 eyes (fraction 0.19) were left aphakic. We did not observe serious intra- or early postoperative complications which might influence the final result of the operation.

SU-E-J-11: Measurement of Eye Lens Dose for Varian On-Board Imaging with Different CBCT Acquisition Techniques

International Nuclear Information System (INIS)

Deshpande, S; Dhote, D; Kumar, R; Thakur, K

2015-01-01

Purpose: To measure actual patient eye lens dose for different cone beam computed tomography (CBCT) acquisition protocol of Varian’s On Board Imagining (OBI) system using Optically Stimulated Luminescence (OSL) dosimeter and study the eye lens dose with patient geometry and distance of isocenter to the eye lens Methods: OSL dosimeter was used to measure eye lens dose of patient. OSL dosimeter was placed on patient forehead center during CBCT image acquisition to measure eye lens dose. For three different cone beam acquisition protocol (standard dose head, low dose head and high quality head) of Varian On-Board Imaging, eye lens doses were measured. Measured doses were correlated with patient geometry and distance between isocenter to eye lens. Results: Measured eye lens dose for standard dose head was in the range of 1.8 mGy to 3.2 mGy, for high quality head protocol dose was in range of 4.5mGy to 9.9 mGy whereas for low dose head was in the range of 0.3mGy to 0.7mGy. Dose to eye lens is depends upon position of isocenter. For posterioraly located tumor eye lens dose is less. Conclusion: From measured doses it can be concluded that by proper selection of imagining protocol and frequency of imaging, it is possible to restrict the eye lens dose below the new limit set by ICRP. However, undoubted advantages of imaging system should be counter balanced by careful consideration of imaging protocol especially for very intense imaging sequences for Adoptive Radiotherapy or IMRT

Optical integration of Pancharatnam-Berry phase lens and dynamical phase lens

International Nuclear Information System (INIS)

Ke, Yougang; Liu, Yachao; Zhou, Junxiao; Liu, Yuanyuan; Luo, Hailu; Wen, Shuangchun

2016-01-01

In the optical system, most elements such as lens, prism, and optical fiber are made of silica glass. Therefore, integrating Pancharatnam-Berry phase elements into silica glass has potential applications in the optical system. In this paper, we take a lens, for example, which integrates a Pancharatnam-Berry phase lens into a conventional plano-convex lens. The spin states and positions of focal points can be modulated by controlling the polarization states of the incident beam. The proposed lens has a high transmission efficiency, and thereby acts as a simple and powerful tool to manipulate spin photons. Furthermore, the method can be conveniently extended to the optical fiber and laser cavity, and may provide a route to the design of the spin-photonic devices.

The effect of contact lens usage on corneal biomechanical parameters in myopic patients.

Science.gov (United States)

Cankaya, Ali B; Beyazyildiz, Emrullah; Ileri, Dilek; Ozturk, Faruk

2012-07-01

To determine and compare the corneal biomechanical properties in myopic patients who use contact lenses and those who do not use contact lenses. The study consisted of 56 myopic patients who used contact lenses (study group) and 123 myopic patients who did not use contact lenses (control group). Intraocular pressure (IOP) was measured with an ocular response analyzer (ORA) and a Goldmann applanation tonometer. Central corneal thickness was measured with an ultrasonic pachymeter. Axial length and anterior chamber depth measurements were acquired with contact ultrasound A-scan biometry. The differences in ORA parameters between study and control group participants were analyzed. The mean corneal hysteresis in study and control groups was 10.1 ± 1.6 mm Hg (6.5-15.9 mm Hg) and 9.7 ± 1.5 mm Hg (6.3-14.2 mm Hg), respectively (P = 0.16). The mean corneal resistance factor was 10.4 ± 1.9 mm Hg (4.6-15.5 mm Hg) in the study group compared with 9.6 ± 1.9 mm Hg (5.1-15.0 mm Hg) in the control group. The difference for corneal resistance factor was statistically significant (P = 0.014). There was no significant difference in corneal-compensated IOP (P = 0.24). Mean Goldmann-correlated IOP was significantly higher in the study group than in control subjects (15.8 ± 3.2 vs. 14.7 ± 3.7 mm Hg) (P = 0.044). None of the corneal biomechanical parameters was significantly correlated to duration of contact lens usage in the study group. Our results suggest that ORA-generated parameters may be different in subjects with and without contact lens usage. Further longitudinal studies need to be performed to establish the relevance of our results.

Converging or Diverging Lens?

Science.gov (United States)

Branca, Mario

2013-01-01

Why does a lens magnify? Why does it shrink objects? Why does this happen? The activities that we propose here are useful in helping us to understand how lenses work, and they show that the same lens can have different magnification capabilities. A converging lens can also act as a diverging lens. (Contains 4 figures.)

Laparoscopic repair of penetrating injury of the diaphragm: an experience from a district hospital

Directory of Open Access Journals (Sweden)

Ali Yahya

2008-01-01

Full Text Available In this study we review our experience in using laparoscopy as a diagnostic and therapeutic tool in dealing with penetrating diaphragmatic injuries due to stab wounds and look at the feasibility of using this procedure in other similar institutions.Thirty patients, all of whom were males 20-30 years of age, presented to the surgical emergency unit of our hospital with upper abdominal and lower chest wall stab wounds between 01-05-1998 and 30-11-2006. Diagnosis of the diaphragm injury was either obvious with omentum herniating through the chest wall, or occult with confirmation of the injury at laparoscopy.All patients underwent diagnostic laparoscopy, which resulted in identification and efficient treatment of eight patients with diaphragmatic injury, and thereby laparotomy was avoided. The procedure converted to open surgery in one patient because of a small left-sided colonic tear. Laparoscopy is an efficient tool for the diagnosis and management of diaphragmatic injuries. It should be used routinely instead of exploratory laparotomy in haemodynamically stable patients with penetrating lower chest injuries.

Experimental Characterization of Piezoelectric Radial Field Diaphragms for Fluidic Control

Science.gov (United States)

Bryant, R. G.; Kavli, S. E.; Thomas, R. A., Jr.; Darji, K. J.; Mossi, K. M.

2004-01-01

NASA has recently developed a new piezoelectric actuator, the Radial Field Diaphragm or RFD. This actuator uses a radially-directed electric field to generate concentric out-of-plane (Z-axis) motion that allows this packaged device to be used as a pump or valve diaphragm. In order to efficiently use this new active device, experimental determination of pressure, flow rate, mechanical work, power consumption and overall efficiency needs to be determined by actually building a pump. However, without an optimized pump design, it is difficult to assess the quality of the data, as these results are inherent to the actual pump. Hence, separate experiments must be conducted in order to generate independent results to help guide the design criteria and pump quality. This paper focuses on the experiments used to generate the RFD's operational parameters and then compares these results to the experimentally determined results of several types of ball pumps. Also discussed are how errors are inherently introduced into the experiments, the pump design, experimental hardware and their effects on the overall system efficiency.

Eye lens dosimetry in interventional cardiology: Results of staff dose measurements and link to patient dose levels

International Nuclear Information System (INIS)

Antic, V.; Ciraj-Bjelac, O.; Rehani, M.; Aleksandric, S.; Arandjic, D.; Ostojic, M.

2013-01-01

Workers involved in interventional cardiology procedures receive high eye lens dose if protection is not used. Currently, there is no suitable method for routine use for the measurement of eye dose. Since most angiography machines are equipped with suitable patient dosemeters, deriving factors linking staff eye doses to the patient doses can be helpful. In this study the patient kerma-area product, cumulative dose at an interventional reference point and eye dose in terms of Hp(3) of the cardiologists, nurses and radiographers for interventional cardiology procedures have been measured. Correlations between the patient dose and the staff eye dose were obtained. The mean eye dose was 121 mSv for the first operator, 33 mSv for the second operator/nurse and 12 mSv for radiographer. Normalised eye lens doses per unit kerma-area product were 0.94 mSv Gy -1 cm -2 for the first operator, 0.33 mSv Gy -1 cm -2 for the second operator/nurse and 0.16 mSv Gy -1 cm -2 for radiographers. Statistical analysis indicated that there is a weak but significant (p < 0.01) correlation between the eye dose and the kerma-area product for all three staff categories. These values are based on a local practice and may provide useful reference for other studies for validation and for wider utilisation in assessing the eye dose using patient dose values. (authors)

Clinical assessment of diclofenac sodium eye drops in toric intraocular lens implantation

Directory of Open Access Journals (Sweden)

Yan Luo

2013-05-01

Full Text Available AIM:To evaluate the application of diclofenac sodium eye drops in toric intraocular lens implantation. METHODS: From January 2011 to February 2012, 38 eyes of 37 patients, who underwent toric intraocular lens implantation in this hospital, were randomly divided into diclofenac sodium eye drops group(trial groupand control group. Patient's degree of cooperation during surgery and inflammation postoperation after 1 day, 3,7, days, 1 month and 3 months were evaluated. RESULTS: Patient's degree of cooperation during surgery in the trial group(1.53±0.62was significantly better than in the control group(2.40±0.88, P<0.05. Inflammation reaction was gentle in the trial group 1 day postoperatively. CONCLUSION: Diclofenac sodium eye drops used during toric intraocular lens implantation can obviously alleviate eye irritation, and increase the cooperation of patients.

Placement of a crystalline lens and intraocular lens: Retinal image quality.

Science.gov (United States)

Siedlecki, Damian; Nowak, Jerzy; Zajac, Marek

2006-01-01

The influence of changes of both crystalline lens and intraocular lens (IOL) misalignment on the retinal image quality was investigated. The optical model of the eye used in investigations was the Liou-Brennan model, which is commonly considered as one of the most anatomically accurate. The original crystalline lens from this model was replaced with an IOL, made of rigid polymethylmethacrylate, in a way that recommend obligatory procedures. The modifications that were made both for crystalline lens and IOL were the longitudinal, the transversal, and the angular displacement.

Early lens extraction with intraocular lens implantation for the treatment of primary angle closure glaucoma: an economic evaluation based on data from the EAGLE trial

Science.gov (United States)

Javanbakht, Mehdi; Azuara-Blanco, Augusto; Burr, Jennifer M; Ramsay, Craig; Cooper, David; Cochran, Claire; Norrie, John; Scotland, Graham

2017-01-01

Objective To investigate the cost-effectiveness of early lens extraction with intraocular lens implantation for the treatment of primary angle closure glaucoma (PACG) compared to standard care. Design Cost-effectiveness analysis alongside a multicentre pragmatic two-arm randomised controlled trial. Patients were followed-up for 36 months, and data on health service usage and health state utility were collected and analysed within the trial time horizon. A Markov model was developed to extrapolate the results over a 5-year and 10-year time horizon. Setting 22 hospital eye services in the UK. Population Males and females aged 50 years or over with newly diagnosed PACG or primary angle closure (PAC). Interventions Lens extraction compared to standard care (ie, laser iridotomy followed by medical therapy and glaucoma surgery). Outcome measures Costs of primary and secondary healthcare usage (UK NHS perspective), quality-adjusted life years (QALYs) and the incremental cost-effectiveness ratio (ICER) for lens extraction versus standard care. Results The mean age of participants was 67.5 (8.42), 57.5% were women, 44.6% had both eyes eligible, 1.4% were of Asian ethnicity and 35.4% had PAC. The mean health service costs were higher in patients randomised to lens extraction: £2467 vs £1486. The mean adjusted QALYs were also higher with early lens extraction: 2.602 vs 2.533. The ICER for lens extraction versus standard care was £14 284 per QALY gained at three years. Modelling suggests that the ICER may drop to £7090 per QALY gained by 5 years and that lens extraction may be cost saving by 10 years. Our results are generally robust to changes in the key input parameters and assumptions. Conclusions We find that lens extraction has a 67–89% chance of being cost-effective at 3 years and that it may be cost saving by 10 years. Trial registration number ISRCTN44464607; Results. PMID:28087548

Emphysema quantification from CT scans using novel application of diaphragm curvature estimation: comparison with standard quantification methods and pulmonary function data

Science.gov (United States)

Keller, Brad M.; Reeves, Anthony P.; Yankelevitz, David F.; Henschke, Claudia I.; Barr, R. Graham

2009-02-01

Emphysema is a disease of the lungs that destroys the alveolar air sacs and induces long-term respiratory dysfunction. CT scans allow for the imaging of the anatomical basis of emphysema and quantification of the underlying disease state. Several measures have been introduced for the quantification emphysema directly from CT data; most,however, are based on the analysis of density information provided by the CT scans, which vary by scanner and can be hard to standardize across sites and time. Given that one of the anatomical variations associated with the progression of emphysema is the flatting of the diaphragm due to the loss of elasticity in the lung parenchyma, curvature analysis of the diaphragm would provide information about emphysema from CT. Therefore, we propose a new, non-density based measure of the curvature of the diaphragm that would allow for further quantification methods in a robust manner. To evaluate the new method, 24 whole-lung scans were analyzed using the ratios of the lung height and diaphragm width to diaphragm height as curvature estimates as well as using the emphysema index as comparison. Pearson correlation coefficients showed a strong trend of several of the proposed diaphragm curvature measures to have higher correlations, of up to r=0.57, with DLCO% and VA than did the emphysema index. Furthermore, we found emphysema index to have only a 0.27 correlation to the proposed measures, indicating that the proposed measures evaluate different aspects of the disease.

First contact diagnosis and management of contact lens-related complications.

Science.gov (United States)

Fagan, Xavier J; Jhanji, Vishal; Constantinou, Marios; Amirul Islam, F M; Taylor, Hugh R; Vajpayee, Rasik B

2012-08-01

To describe the spectrum of contact lens-related problems in cases presenting to a tertiary referral eye hospital. A retrospective case record analysis of 111 eyes of 97 consecutive patients was undertaken over a period of five months at the Royal Victorian Eye and Ear Hospital, Melbourne, Australia. Contact lens-related complications (CLRC) were classified into microbial keratitis, sterile corneal infiltrates, corneal epitheliopathy and contact lens-related red eye (CLARE). Main parameters examined were nature of the first contact, clinical diagnosis, and management pattern. Forty-two percent of the initial presentations were to health care practitioners (HCPs) other than ophthalmologists. Mean duration from the onset of symptoms to presentation was 6.3 ± 10.9 days. Forty-nine percent (n = 54) of patients had an associated risk factor, most commonly overnight use of contact lenses (n = 14, 13 %). Most common diagnosis at presentation was corneal epitheliopathy (68 %) followed by sterile infiltrates (10 %), CLARE (8 %) and microbial keratitis (6 %). No significant differences were found in the pattern of treatment modalities administered by ophthalmologists and other HCPs. HCPs other than ophthalmologists are the first contact for contact lens-related problems in a significant proportion of patients. These HCPs manage the majority of CLRC by direct treatment or immediate referral.

Refractive neutron lens

International Nuclear Information System (INIS)

Petrov, P.V.; Kolchevsky, N.N.

2013-01-01

Model of the refractive neutron lens is proposed. System of N lenses acts as one thin lens with a complex refraction index n*. The maximum number N max of individual lenses for 'thick' neutron lens is calculated. Refractive neutron lens properties (resolution, focal depth) as function of resolution factor F 0 =ρbc/μ and depth of field factor dF 0 =λF 0 =λρbc/μ are calculated. It is shown that micro resolution of the refractive neutron optics is far from the wavelength in size and its open possibilities for progress in refractive neutron optics. (authors)

Rupture traumatique du diaphragme au CHU Gabriel Touré de ...

African Journals Online (AJOL)

Rupture traumatique du diaphragme au CHU Gabriel Touré de Bamako, Mali. B T Dembélé, A Togo, A Traoré, Y Sidibé, M Konaté, A A Traoré, A Bah, T Koné, I Tounkara, L Kanté, I Diakité, B Karembé, A Koné, M.I Mangane, G Diallo ...

Hand hygiene prior to contact lens handling is problematical.

Science.gov (United States)

McMonnies, Charles W

2012-04-01

To establish guidelines for contact lens wearers' hand hygiene practices which achieve a balance between minimising risk of infection and reasonable expectations on the ability of patients to follow them. Evidence has been obtained from publications via PubMed, Advanced Medline Search, Cochrane Reviews, Google Scholar and using the key words hand hygiene, washing and contact lens. Guidelines for effective hand washing and the bother involved vary according to the level of hygiene required. High levels of non-compliance with hand hygiene practices, even among healthcare workers, gives an indication of how important the level of bother involved when following guidelines can be in contributing to non-compliance. Better patient education to improve hand washing techniques as well as patient attitudes toward hand hygiene are needed to reduce high non-compliance levels. Better hand hygiene techniques and higher frequency of their application give the prospect of reduced risk of infection and of any discomfort that arises from increased lens and ocular bioburden. In order that adoption rates might be maximised, the guidelines which have been distilled from this review attempt to strike a balance between technique redundancy and the associated higher levels of hygiene achieved and the possibility that the perception of too much bother involved could reduce participation rates. The guidelines have been expanded by the inclusion of suggested explanatory information in the expectation that helping patients to understand why the recommendations are made will have the effect of increasing their adoption. Copyright © 2011 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Mycobacterium avium subsp. avium in lymph nodes and diaphragms of pigs from one infected herd in the Czech Republic.

Science.gov (United States)

Kriz, Petr; Kaevska, Marija; Slana, Iva; Bartejsova, Iva; Pavlik, Ivo

2014-01-01

This study was performed on 40 finished pigs from one herd naturally infected with Mycobacterium avium subsp. avium. The aim was to investigate the presence and amount of M. a. avium in samples of lymph nodes and diaphragm tissues collected during routine postmortem inspection using the triplex quantitative real time PCR (qPCR) method. We collected, in total, 107 samples: various lymph nodes affected by gross tuberculosis (TB)-like lesions from 17 pig carcasses, as well as samples of head and mesenteric lymph nodes from 23 carcasses without TB-like lesions. Samples of diaphragm tissues were collected from all carcasses. M. a. avium was detected in one or more tissue samples collected from half of the slaughtered pigs tested. Samples of diaphragm tissues of three pigs with detected TB-like lesions contained M. a. avium (10(2) to 10(3) cells per g of sample); the organism was not detected in diaphragm tissues from pigs without TB-like lesions. The qPCR method may be useful for quantification of M. a. avium in pigs for the purposes of foodborne risk assessment.

Radiation Dose to the Lens of the Eye from Computed Tomography Scans of the Head

Science.gov (United States)

Januzis, Natalie Ann

While it is well known that exposure to radiation can result in cataract formation, questions still remain about the presence of a dose threshold in radiation cataractogenesis. Since the exposure history from diagnostic CT exams is well documented in a patient's medical record, the population of patients chronically exposed to radiation from head CT exams may be an interesting area to explore for further research in this area. However, there are some challenges in estimating lens dose from head CT exams. An accurate lens dosimetry model would have to account for differences in imaging protocols, differences in head size, and the use of any dose reduction methods. The overall objective of this dissertation was to develop a comprehensive method to estimate radiation dose to the lens of the eye for patients receiving CT scans of the head. This research is comprised of a physics component, in which a lens dosimetry model was derived for head CT, and a clinical component, which involved the application of that dosimetry model to patient data. The physics component includes experiments related to the physical measurement of the radiation dose to the lens by various types of dosimeters placed within anthropomorphic phantoms. These dosimeters include high-sensitivity MOSFETs, TLDs, and radiochromic film. The six anthropomorphic phantoms used in these experiments range in age from newborn to adult. First, the lens dose from five clinically relevant head CT protocols was measured in the anthropomorphic phantoms with MOSFET dosimeters on two state-of-the-art CT scanners. The volume CT dose index (CTDIvol), which is a standard CT output index, was compared to the measured lens doses. Phantom age-specific CTDIvol-to-lens dose conversion factors were derived using linear regression analysis. Since head size can vary among individuals of the same age, a method was derived to estimate the CTDIvol-to-lens dose conversion factor using the effective head diameter. These conversion

Lens densitometry after corneal cross-linking in patients with keratoconus using a Scheimpflug camera

Directory of Open Access Journals (Sweden)

Alireza Baradaran-Rafii

2015-01-01

Conclusion: In this short term study with six months' follow-up, we observed no significant impact on lens density following exposure of the crystalline lens to ultraviolet A and riboflavin free radicals in the CXL procedure.

Ultrastructural effects of silicone oil on the clear crystalline lens of the human eye.

Science.gov (United States)

Soliman, Wael; Sharaf, Mohamed; Abdelazeem, Khaled; El-Gamal, Dalia; Nafady, Allam

2018-03-01

To evaluate light and electron microscopic changes of the anterior capsule and its epithelium after clear lens extraction of vitrectomized myopic eyes with silicone oil tamponade. This prospective, controlled, non-randomized, interventional study included 20 anterior lens capsular specimens that were excised during combined clear lens extraction and silicone oil removal from previously vitrectomized highly myopic patients with silicone oil tamponade for previous retinal detachment surgeries. The specimens were examined via light microscopy and electron microscopy and compared with 20 anterior capsule specimens removed during clear lens extraction of non-vitrectomized highly myopic eyes. Light microscopic examination of clear lens anterior capsule specimens of vitrectomized myopic eyes filled with silicone oil showed relatively more flat cells with irregular outline of lens' epithelial cells with wide intercellular spaces, deeply stained nuclei, and multiple intracytoplasmic vacuoles. Scanning electron microscopy revealed collagenous surfaces filled with multiple pits, depressions, and abnormal deposits. Transmission electron microscopy revealed lens epithelial cells with apoptotic changes, many cytoplasmic vacuoles, and filopodia-like protrusions between lens epithelial cells and the capsule. Epithelial proliferation and multilayering were also observed. silicone oil may play a role in the development of apoptotic and histopathological changes in clear lens epithelial cells. Clarity of the lens at the time of silicone oil removal does not indicate an absence of cataractous changes. We found justification of combined clear lens extraction and silicone oil removal or combined phacovitrectomy when silicone oil injection is planned, but further long-term studies with larger patient groups are required.

Radiation dose to the eye lens

DEFF Research Database (Denmark)

Baun, Christina; Falch Braas, Kirsten; D. Nielsen, Kamilla

2015-01-01

Radiation Dose to the Eye Lens: Does Positioning Really Matter? C. Baun1, K. Falch1, K.D. Nielsen2, S. Shanmuganathan1, O. Gerke1, P.F. Høilund-Carlsen1 1Department of Nuclear Medicine, Odense University Hospital, Odense C, Denmark. 2University College Lillebaelt, Odense, Denmark. Aim: The scan...... field in oncology patients undergoing eyes-to-thighs PET/CT must always include the base of the scull according to department guidelines. The eye lens is sensitive to radiation exposure and if possible it should be avoided to scan the eye. If the patient’s head is kipped backwards during the scan one...... might avoid including the eye in the CT scan without losing sufficient visualization of the scull base. The aim of this study was to evaluate the possibility of decreasing the radiation dose to the eye lens, simply by changing the head position, when doing the PET/CT scan from the base of the scull...

Exchange of tears under a contact lens is driven by distortions of the contact lens.

Science.gov (United States)

Maki, Kara L; Ross, David S

2014-12-01

We studied the flow of the post-lens tear film under a soft contact lens to understand how the design parameters of contact lenses can affect ocular health. When a soft contact lens is inserted, the blinking eyelid causes the lens to stretch in order to conform to the shape of the eye. The deformed contact lens acts to assume its un-deformed shape and thus generates a suction pressure in the post-lens tear film. In consequence, the post-lens tear fluid moves; it responds to the suction pressure. The suction pressure may draw in fresh fluid from the edge of the lens, or it may eject fluid there, as the lens reassumes its un-deformed shape. In this article, we develop a mathematical model of the flow of the post-lens tear fluid in response to the mechanical suction pressure of a deformed contact lens. We predict the amount of exchange of fluid exchange under a contact lens and we explore the influence of the eye's shape on the rate of exchange of fluid. © The Author 2014. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Peripheral Defocus of the Monkey Crystalline Lens With Accommodation in a Lens Stretcher

Science.gov (United States)

Maceo Heilman, Bianca; Manns, Fabrice; Ruggeri, Marco; Ho, Arthur; Gonzalez, Alex; Rowaan, Cor; Bernal, Andres; Arrieta, Esdras; Parel, Jean-Marie

2018-01-01

Purpose To characterize the peripheral defocus of the monkey crystalline lens and its changes with accommodation. Methods Experiments were performed on 15 lenses from 11 cynomolgus monkey eyes (age: 3.8–12.4 years, postmortem time: 33.5 ± 15.3 hours). The tissue was mounted in a motorized lens stretcher to allow for measurements of the lens in the accommodated (unstretched) and unaccommodated (stretched) states. A custom-built combined laser ray tracing and optical coherence tomography system was used to measure the paraxial on-axis and off-axis lens power for delivery angles ranging from −20° to +20° (in air). For each delivery angle, peripheral defocus was quantified as the difference between paraxial off-axis and on-axis power. The peripheral defocus of the lens was compared in the unstretched and stretched states. Results On average, the paraxial on-axis lens power was 52.0 ± 3.4 D in the unstretched state and 32.5 ± 5.1 D in the stretched state. In both states, the lens power increased with increasing delivery angle. From 0° to +20°, the relative peripheral lens power increased by 10.7 ± 1.4 D in the unstretched state and 7.5 ± 1.6 D in the stretched state. The change in field curvature with accommodation was statistically significant (P lens has greater curvature or relative peripheral power. Conclusions The cynomolgus monkey lens has significant accommodation-dependent curvature of field, which suggests that the lens asserts a significant contribution to the peripheral optical performance of the eye that also varies with the state of accommodation.

[Comparative analysis of visual function and the quality of life index with eyeglasses or a progressive contact lens].

Science.gov (United States)

Sant'Anna, Neusa Vidal; Schor, Paulo; Lipener, César; Uras, Ricardo

2006-01-01

To compare the visual function and the answers to a questionnaire of quality of life of patients wearing a progressive contact lens or eyeglasses. The Focus Progressive contact lens had been fitted in 35 patients with far visual acuity with progressive-addition eyeglasses equal to zero (log MAR) and near J1 (Jaeger). The far and near visual acuities and the measurement of contrast sensitivity were compared when the patients were wearing the eyeglasses or the contact lens and the patients' results of the scores of the quality of life questionnaire (NEI VFQ-25) were analyzed statistically considering the type of ametropy and the age. The far and near visual acuities and the contrast sensitivity measurement were worse with the contact lens than with eyeglasses. The answers to the questionnaire did not differ when were comparing the same patients wearing eyeglasses or contact lens, no matter the type of ametropy. The myopic and the hyperopic subgroups had worse answers to the quality of life questionnaire when corrected with the contact lens than with eyeglasses, both with age equal to or less than their median. The visual function was worse with the contact lens. The type of ametropy did not influence the answers to the quality of life questionnaire considering the optical correction, but age did.

Method of production of a diaphragm for instruments in particle optics and diaphragm fabricated by this method

International Nuclear Information System (INIS)

Sandrik, J.; Krohne, P.

1975-01-01

The production method of, e.g., a circular diaphragm for an electron microscope is based on copper plate as supporting material. A light-sensitive, electrically insulating layer is coated on this. After exposing and freeing the positions of this layer, e.g., the circular interior as well as the cross-piece to the exterior of the diaghragm, a galvanic building-up of a noble metal layer follows, e.g. gold, on these now free positions. After freeing the remaining non-exposed material, an etching-protective lacquer is coated on the positions of the supporting material which are to be maintained. The remaining parts of the supporting material are then removed by positive etching. (DG/LH) [de

Comparative analysis of the nuclear lens opalescence by the Lens Opacities Classification System III with nuclear density values provided by Oculus Pentacam: a cross-section study using Pentacam Nucleus Staging software

Directory of Open Access Journals (Sweden)

Fernanda Pedreira Magalhães

2011-04-01

Full Text Available PURPOSE: To compare the clinical classification of cataract using the Lens Opacities Classification System (LOCS III with the mean values of lens density provided by the Pentacam Scheimpflug System in nuclear cataracts. METHODS: One hundred and one eyes from 101 patients with age-related nuclear cataract were submitted to clinical examination for lens grading score using LOCS III. According to LOCS III, nuclear opalescence was divided in six groups. Patients were evaluated by the Pentacam Scheimpflug System for the mean lens density using the Pentacam lens densitometry program (PLDP, the Pentacam Nucleus Staging (PNS mean value and the PNS cataract grading score. RESULTS: A positive correlation between the mean values of lens density and LOCS III classification, considering groups 1 to 5, could be noticed with PLDP and PNS mean value. The mean values between the groups were similar using the PLDP and the PNS mean value. However, when the PNS cataract grading score was evaluated, there was low correspondence with LOCS III classification. CONCLUSION: Pentacam Scheimpflug device offers an objective measure of the lens nuclear density on nuclear cataracts. PLDP and the PNS mean value were both useful to evaluate age-related nuclear cataract up to LOCS III group 5.

Hydrophil diaphragms on the basis of perfluorated copolymers FEP and polyacryl nitrile: Manufacture by radiation- initiated grafting and their use for pervaporation

International Nuclear Information System (INIS)

Scholz, H.

1986-01-01

The radiation-initiated grafting copolymerisation of hydrophil monomers to FEP, a copolymer of tetrafluorethene and hexafluorpropene and to polyacryl nitrile (PAN) was examined in this dissertation. The grafted products were used as diaphragms for the separation of water-ethanol mixtures by pervaporation. Water was separated through the diaphragm from the mixture in the pervaporation experiments. It was shown how the mechanical properties of the basic polymer affect the interaction between basic polymer and grafted polymer and how the grafting conditions affect the diaphragm properties. By grafting acrylic acid on to the basic polymers FEP and PAN, very good results were achieved for the water-ethanol separation, if the diaphragms were used in the K form. The selectivity of PAN-g-acrylic acid-K for water reached values of α > 1000. (orig./RB) [de

Changes in lens stiffness due to capsular opacification in accommodative lens refilling

NARCIS (Netherlands)

Nibourg, Lisanne M.; Sharma, Prashant K.; van Kooten, Theo G.; Koopmans, Steven A.

Accommodation may be restored to presbyopic lenses by refilling the lens capsular bag with a soft polymer. After this accommodative lens refilling prevention of capsular opacification is a requirement, since capsular opacification leads to a decreased clarity of the refilled lens. It has been

Bending-induced electromechanical coupling and large piezoelectric response in a micromachined diaphragm

KAUST Repository

Wang, Zhihong; Yao, Yingbang; Wang, Xianbin; Yue, Weisheng; Chen, Longqing; Zhang, Xixiang

2013-01-01

We investigated the dependence of electromechanical coupling and the piezoelectric response of a micromachined Pb(Zr 0.52 Ti 0.48)O 3 (PZT) diaphragm on its curvature by observing the impedance spectrum and central deflection responses to a small AC

Evaluation of bubbler/diaphragm techniques to measure surface level in the waste storage tanks

International Nuclear Information System (INIS)

Peters, T.J.; Hickman, B.J.; Colson, J.B.

1993-10-01

This report describes the results of tests conducted at the Pacific Northwest Laboratory (PNL) to determine if a bubbler technique can be used to determine the surface level in the waste tanks. Two techniques were evaluated. The first technique is a standard bubbler system in which a tube is placed below the surface of the liquid to be measured and air pressure inside a tube is increased until bubbles begin to become emitted from the tube. The air pressure then is a function of the pressure at the bottom of the tube. The second technique involves a system similar to the standard bubbler technique, but instead of bubbles being released into the material to be gauged, air pressure is increased against a diaphragm until enough pressure is applied to overcome the pressure of the liquid at the given depth, at which time the air then flows in a return loop back to a vent. The advantage of the diaphragm system is that it is a sealed system; thus no air is released into the waste tank materials, and it is not possible for the waste tank materials to get into the air flow. Based on the results of the tests conducted in this program, it appears that the bubbler and diaphragm systems that were tested could not be used for accurate measurements of the level in the waste tanks. Both exhibited deposits of simulated waste tank material at the end of the devices which affected the ability of the gauge to accurately determine changes in the surface level even though the measured value of the level was inaccurate. Further investigations into the cause of this inaccuracy may be warranted. Alternate diaphragm materials may improve the performance of this gauge

Contribution of oxidative stress to pathology in diaphragm and limb muscles with Duchenne muscular dystrophy.

Science.gov (United States)

Kim, Jong-Hee; Kwak, Hyo-Bum; Thompson, LaDora V; Lawler, John M

2013-02-01

Duchenne muscular dystrophy (DMD) is a degenerative skeletal muscle disease that makes walking and breathing difficult. DMD is caused by an X-linked (Xp21) mutation in the dystrophin gene. Dystrophin is a scaffolding protein located in the sarcolemmal cytoskeleton, important in maintaining structural integrity and regulating muscle cell (muscle fiber) growth and repair. Dystrophin deficiency in mouse models (e.g., mdx mouse) destabilizes the interface between muscle fibers and the extracellular matrix, resulting in profound damage, inflammation, and weakness in diaphragm and limb muscles. While the link between dystrophin deficiency with inflammation and pathology is multi-factorial, elevated oxidative stress has been proposed as a central mediator. Unfortunately, the use of non-specific antioxidant scavengers in mouse and human studies has led to inconsistent results, obscuring our understanding of the importance of redox signaling in pathology of muscular dystrophy. However, recent studies with more mechanistic approaches in mdx mice suggest that NAD(P)H oxidase and nuclear factor-kappaB are important in amplifying dystrophin-deficient muscle pathology. Therefore, more targeted antioxidant therapeutics may ameliorate damage and weakness in human population, thus promoting better muscle function and quality of life. This review will focus upon the pathobiology of dystrophin deficiency in diaphragm and limb muscle primarily in mouse models, with a rationale for development of targeted therapeutic antioxidants in DMD patients.

Oral omega-6 essential fatty acid treatment in contact lens associated dry eye.

Science.gov (United States)

Kokke, Karolien H; Morris, Judith A; Lawrenson, John G

2008-06-01

Symptoms of dry eye are commonly reported in contact lens wearers and are a frequent cause of non-tolerance. The purpose of the present study is to evaluate the effects of oral treatment with particular omega-6 fatty acids in the form of evening primrose oil (EPO) on subjective symptoms, ocular surface signs and tear film characteristic in patients with contact lens associated dry eye. The study design was randomised, double-masked and placebo controlled. 76 female soft contact lens wearers were treated for 6 months with either EPO or placebo (olive oil). Subjects underwent three examinations (baseline, 3 and 6 months). At each examination subjects were given a questionnaire relating to lens comfort and dry eye symptoms and underwent a series of tests of tear film characteristics (tear meniscus height, break-up time), meibomian gland function (lipid layer thickness and quality) and ocular surface parameters (hyperaemia and staining). The EPO group showed a significant improvement in the specific symptom of 'dryness' at 3 and 6 months (porally administered omega-6 fatty acids in alleviating dry eye symptoms and improving overall lens comfort in patients suffering from contact lens associated dry eye.

Contact Lens-Related Eye Infections

Science.gov (United States)

... Español Eye Health / Eye Health A-Z Contact Lens-Related Eye Infections Sections Contact Lens-Related Eye ... Six Steps to Avoid Contact Lens Infections Contact Lens-Related Eye Infections Leer en Español: Infecciones relacionadas ...

ECTOPIC LENS EXTRACTION IN CHILDREN

Directory of Open Access Journals (Sweden)

Vladimir Pfeifer

2002-12-01

Full Text Available Background. Ectopia lentis continues to be a therapeutic challenge for ophthalmologists. It can occur as an isolated condition, after ocular trauma, in association with other ocular disorders, as part of a systemic mesodermal disease or a complication of general metabolic disorders. Minimal subluxation of the lens may cause no visual symptoms, but in more advanced cases serious optical disturbances arise. The most important is amblyopia. Surgical treatment options include iris manipulation, lens discission, aspiration, intracapsular or extracapsular extraction, and pars plana lensectomy. The choice of surgical technique remains controversial, in part because of the historically poor visual results and high rate of perioperative complications, including vitreous loss and retinal detachment.Methods. We describe a surgical technique based on the use of the Cionni endocapsular tension ring, dry irrigation aspiration of lens material, centration of the capsular bag and foldable intraocular lens implantation into the bag. With mentioned surgical technique 8 patients were operated; 4 boys and 4 girls, together 11 eyes.Results. The final BCVA after follow up period improved in 9 eyes and it remained the same as before operation in one eye. Statistical comparison of preoperative and postoperative visual acuities showed significant improvement. On the other hand there was no correlation between preoperative and postoperative visual acuity.Conclusions. This surgical procedure is an alternative approach in solving this challenging cases of ectopia lentis with good postoperative visual rehabilitation.

Eye lens dosimetry for interventional procedures – Relation between the absorbed dose to the lens and dose at measurement positions

International Nuclear Information System (INIS)

Geber, Therese; Gunnarsson, Mikael; Mattsson, Sören

2011-01-01

This study investigated the relationship between the absorbed dose to the lens of the eye and the absorbed dose at different measurement positions near the eye of interventional radiologists. It also visualised the dose distribution inside the head, both when protective eyewear were used and without such protection. The best position for an eye lens dosimeter was found to be at the side of the head nearest to the radiation source, close to the eye. Positioning the dosimeter at the eyebrow could lead to an underestimation of the lens dose of as much as 45%. The measured dose distribution showed that the absorbed dose to the eye lenses was high compared to the other parts of the head, which stresses the importance of wearing protective eyewear. However, many models of eyewear were found to be deficient as the radiation could slip through at several places, e.g. at the cheek. The relationship between the absorbed dose to the lens and the kerma-area-product (P KA ) delivered to the patient was also studied.

Cx43, ZO-1, alpha-catenin and beta-catenin in cataractous lens

Indian Academy of Sciences (India)

Specimens of the anterior lens capsule with an attached monolayer of lens epithelial cells (LECs) were obtained from patients (=52) undergoing cataract surgery. Specimens were divided into three groups based on the type of cataract: nuclear cataract, cortical cataract and posterior subcapsular cataract (PSC).

[Clinical applications of ultrasound biomicroscopy in diagnosis and treatment of lens subluxation].

Science.gov (United States)

Liu, Yi-Zhi; Liu, Yu-Hua; Wu, Ming-Xing; Luo, Li-Xia; Zhang, Xin-Yu; Cai, Xiao-Yu; Chen, Xiu-Qi

2004-03-01

To evaluate the clinical value in diagnosis and treatment of lens subluxation using ultrasound biomicroscopy (UBM). This study comprised 29 patients (32 eyes) that had cataract with subluxated lenses due to different causes admitted into our hospital between November 2000 and January 2002. All eyes received UBM examination preoperatively and postoperatively. Capsular tension ring (CTR) implantations were performed using different technique according to UBM examination. Then all patients received phacoemulsification and intraocular lens (IOL) implantation. The location of IOL and CTR and complications were evaluated postoperatively. Different kinds of subluxated lens shown different manifestations in UBM. The degree of zonular defect can be evaluated with UBM preoperatively. With UBM examination preoperatively, extent of lens subluxation less than 1/2 quadrant in 19 eyes while more than 1/2 quadrant in other 13 eyes were observed. Postoperative UBM examination in this series shown that CTRs were holding in place except one attached to the iris root. IOLs in 29 eyes were in proper position while IOLs in 3 patients were slightly tilted. The degree and extent of lens subluxation can be evaluated using UBM examinations preoperatively, which is necessary in the selection of surgical protocol. With postoperative UBM examinations, a precise observation on the actual location of CTR and IOL can be achieved to produce an objective evaluation of the surgical outcomes.

Vortex gas lens

Science.gov (United States)

Bogdanoff, David W.; Berschauer, Andrew; Parker, Timothy W.; Vickers, Jesse E.

1989-01-01

A vortex gas lens concept is presented. Such a lens has a potential power density capability of 10 to the 9th - 10 to the 10th w/sq cm. An experimental prototype was constructed, and the divergence half angle of the exiting beam was measured as a function of the lens operating parameters. Reasonably good agreement is found between the experimental results and theoretical calculations. The expanded beam was observed to be steady, and no strong, potentially beam-degrading jets were found to issue from the ends of the lens. Estimates of random beam deflection angles to be expected due to boundary layer noise are presented; these angles are very small.

Intraocular lens dislocation after whole-body vibration.

Science.gov (United States)

Vela, José I; Andreu, David; Díaz-Cascajosa, Jesús; Buil, José A

2010-10-01

We present 2 cases of intraocular lens (IOL) dislocation that appeared shortly after the patients exercised on a vibration platform. The first patient was a 71-year-old woman who presented with lens subluxation in her right eye and a complete posterior IOL dislocation in her left eye. The second case was a 62-year-old woman who presented with unilateral IOL dislocation within the capsular bag in her right eye. Timing from IOL implantation to dislocation was approximately 6 years and 4 years, respectively. Pars plana vitrectomy with removal of the dislocated IOL was performed in both patients. Whole-body vibration training has become increasingly popular as a form of exercise training. It reportedly may provide benefits in physical function and in some diseases, especially in older people. However, evidence-based protocols ensuring safety and efficacy in this population are lacking. We discuss vibration as a cause of late IOL dislocation. Copyright © 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Primary anterior chamber intraocular lens for the treatment of severe crystalline lens subluxation.

Science.gov (United States)

Hoffman, Richard S; Fine, I Howard; Packer, Mark

2009-10-01

Subluxated cataractous and clear lenses are commonly treated by limbal or pars plana lensectomy followed by primary or secondary intraocular lens (IOL) implantation. Adjunctive capsular prosthetic devices have facilitated lens removal and IOL centration in these challenging cases but have also added complexity and potential complications to the procedure. Although crystalline lens extraction may be required to clear the visual axis in mild to moderate lens subluxations, we propose insertion of a primary anterior chamber IOL without lens extraction in severe subluxations when the eye is optically aphakic or can be made functionally aphakic following neodymium:YAG laser zonulysis. Two cases demonstrating this approach are presented.

Protection of the eye lens

International Nuclear Information System (INIS)

2015-01-01

The limit of radiation exposure for eye lens is going to decrease dramatically from 150 to 20 mSv as a transposition into the French law of a CIPR (International Commission for Radiation Protection) directive. Sanitary studies have shown that radiologists are more likely by a factor of 3.8 to get eye lens opacities than the rest of the population. The wearing of protective glasses is recommended and in order to get a better monitoring of the radiation dose new dosimeters have been designed, they can be worn on the glass frame of directly stuck on the skin near the eyes. A study has shown that veterinary surgeons that are accustomed to stay near animals to keep them quiet during radiological exams are prone to receive high doses as well as physicians that use hypnosis to decrease the level of anxiety of their patients during radiological exams. Radiation exposure of radiologists can be mitigated through: the use of protective shields and equipment and the optimization of the dose delivered to the patient. (A.C.)

[Hyperopic Laser-in-situ-Keratomileusis after trifocal intraocular lens implantation : Aberration-free femto-Laser-in-situ-Keratomileusis treatment after implantation of a diffractive, multifocal, toric intraocular lens-case analysis].

Science.gov (United States)

Hemkeppler, E; Böhm, M; Kohnen, T

2018-05-29

A 52-year-old highly myopic female patient was implanted with a multifocal, diffractive, toric intraocular lens because of the wish to be independent of eyeglasses. Despite high-quality, extensive preoperative examinations, a hyperopic refractive error remained postoperatively, which led to the patient's dissatisfaction. This error was treated with Laser-in-situ-Keratomileusis (LASIK). After corneal LASIK treatment and implantation of a diffractive toric multifocal intraocular lens the patient showed a good postoperative visual result without optical phenomena.

Developmental plasticity of phrenic motoneuron and diaphragm properties with the inception of inspiratory drive transmission in utero.

Science.gov (United States)

Greer, John J; Martin-Caraballo, Miguel

2017-01-01

The review outlines data consistent with the hypothesis that inspiratory drive transmission that generates fetal breathing movements (FBMs) is essential for the developmental plasticity of phrenic motoneurons (PMNs) and diaphragm musculature prior to birth. A systematic examination during the perinatal period demonstrated a very marked transformation of PMN and diaphragm properties coinciding with the onset and strengthening of inspiratory drive and FBMs in utero. This included studies of age-dependent changes of: i) morphology, neuronal coupling, passive and electrophysiological properties of PMNs; ii) rhythmic inspiratory activity in vitro; iii) FBMs generated in vivo detected by ultrasonography; iv) contractile and end-plate potential properties of diaphragm musculature. We also propose how the hypothesis can be further evaluated with studies of perinatal hypoglossal motoneuron-tongue musculature and the use of Dbx1 null mice that provide an experimental model lacking descending inspiratory drive transmission in utero. Copyright © 2016 Elsevier Inc. All rights reserved.

Treatment of contact lens related dry eye with antibacterial honey.

Science.gov (United States)

Wong, Daniel; Albietz, Julie M; Tran, Huan; Du Toit, Cimonette; Li, Anita Hui; Yun, Tina; Han, Jee; Schmid, Katrina L

2017-12-01

Contact lens induced dry eye affects approximately 50% of contact lens wearers. The aim was to assess the effects of Manuka (Leptospermum sp.) honey eye drops (Optimel, Melcare, Australia) on dry eye in contact lens wearers. The safety of the honey eye drops in contact lens wear and contact lens wearers' compliance were also evaluated. Prospective, randomised, cross over study, examiner masked, pilot treatment trial. Twenty-four participants aged 20 to 55 years with contact lens related dry eye were recruited and randomised to two treatment groups; 20 completed the study. One group used Optimel eye drops twice a day for two weeks followed by conventional lubricant (Systane Ultra, Alcon) therapy for two weeks; the other group completed the treatments in the reverse order. Before and after each treatment dry eye symptomology, ocular surface inflammation, and tear quantity and quality were assessed. Participants completed a daily log detailing their usage of treatments and any issues. Dry eye symptoms improved significantly after Optimel treatment. Patients with more severe symptoms at baseline showed a greater improvement in symptoms. No significant differences were observed in the objective signs of dry eye; presumably because of the short treatment duration. Seventy-five% of contact lens wearers reported good adherence to Optimel treatment and 95% reported no issues using this product. Optimel Eye Drops reduce the symptoms of dry eye in contact lens wearers and are safe to use. A longer treatment period to assess the effect on clinical signs of dry eye is required. Copyright © 2017 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Development of a Hemispherical Metal Diaphragm for Single-Cycle Liquid-Metal Positive Expulsion Systems

National Research Council Canada - National Science Library

Gorland, Sol

1965-01-01

This report presents experimental results pertaining to the design and development of a metallic expulsion diaphragm for single-cycle positive expulsion of high-temperature liquid in an agravity condition...

The safety and efficacy of contact lens wear in the industrial and chemical workplace.

Science.gov (United States)

Tyhurst, Keith; McNett, Ryan; Bennett, Edward

2007-11-01

The use and safety of contact lenses in the industrial and chemical workplace has often been questioned since the 1960s because of many unconfirmed reports of ocular injury resulting from contact lens wear. Because of these urban legends, contact lens wear has been banned or wearers have been required to wear additional personal protective equipment (PPE) not required of non-contact lens wearers. Literature review via Medline and Google search. Research has shown that contact lenses typically provide protective benefits that decrease the severity of ocular injury and improve worker performance. While contact lens wear contraindications do exist, in most cases, and with proper precautions, contact lens wear is still possible. Industrial and chemical companies need to establish written contact lens use policies based on current studies that have shown the safety of workplace contact lens wear when combined with the same PPE required of non-contact lens wearers. Practitioners need to discuss, with their contact lens patients, the additional responsibilities required to maintain proper lens hygiene and proper PPE in the workplace.

Capsular 'pits' in the human lens.

OpenAIRE

Harris, M. L.; Brown, N. A.; Shun-Shin, G. A.; Smith, G. T.

1992-01-01

The lens capsule is an atypical basement membrane surrounding the lens epithelial cells and lens fibres which make up the remainder of the human lens. A seemingly unreported morphological change visible in the lens capsule with the biomicroscope is described.

Recovery of muscle function after deep neuromuscular block by means of diaphragm ultrasonography and adductor of pollicis acceleromyography with comparison of neostigmine vs. sugammadex as reversal drugs: study protocol for a randomized controlled trial.

Science.gov (United States)

Cappellini, Iacopo; Picciafuochi, Fabio; Ostento, Daniele; Danti, Ginevra; De Gaudio, Angelo Raffaele; Adembri, Chiara

2018-02-21

The extensive use of neuromuscular blocking agents (NMBAs) during surgical procedures still leads to potential residual paralyzing effects in the postoperative period. Indeed, neuromuscular monitoring in an intra-operative setting is strongly advocated. Acetylcholinesterase inhibitors can reverse muscle block, but their short half-life may lead to residual curarization in the ward, especially when intermediate or long-acting NMBAs have been administered. Sugammadex is the first selective reversal drug for steroidal NMBAs; it has been shown to give full and rapid recovery of muscle strength, thus minimizing the occurrence of residual curarization. Acceleromyography of the adductor pollicis is the gold standard for detecting residual curarization, but it cannot be carried out on conscious patients. Ultrasonography of diaphragm thickness may reveal residual effects of NMBAs in conscious patients. This prospective, double-blind, single-center randomized controlled study will enroll patients (of American Society of Anesthesiologists physical status I-II, aged 18-80 years) who will be scheduled to undergo deep neuromuscular block with rocuronium for ear, nose, or throat surgery. The study's primary objective will be to compare the effects of neostigmine and sugammadex on postoperative residual curarization using two different tools: diaphragm ultrasonography and acceleromyography of the adductor pollicis. Patients will be extubated when the train-of-four ratio is > 0.9. Diaphragm ultrasonography will be used to evaluate the thickening fraction, which is the difference between the end expiratory thickness and the end inspiratory thickness, normalized to the end expiratory thickness. Ultrasonography will be performed before the initiation of general anesthesia, before extubation, and 10 and 30 min after discharging patients from the operating room. The secondary objective will be to compare the incidence of postoperative complications due to residual neuromuscular

Oxidative damage induced by cigarette smoke exposure in mice: impact on lung tissue and diaphragm muscle,

Directory of Open Access Journals (Sweden)

Samanta Portão de Carlos

2014-08-01

Full Text Available OBJECTIVE: To evaluate oxidative damage (lipid oxidation, protein oxidation, thiobarbituric acid-reactive substances [TBARS], and carbonylation and inflammation (expression of phosphorylated AMP-activated protein kinase and mammalian target of rapamycin [p-AMPK and p-mTOR, respectively] in the lung parenchyma and diaphragm muscles of male C57BL-6 mice exposed to cigarette smoke (CS for 7, 15, 30, 45, or 60 days. METHODS: Thirty-six male C57BL-6 mice were divided into six groups (n = 6/group: a control group; and five groups exposed to CS for 7, 15, 30, 45, and 60 days, respectively. RESULTS: Compared with control mice, CS-exposed mice presented lower body weights at 30 days. In CS-exposed mice (compared with control mice, the greatest differences (increases in TBARS levels were observed on day 7 in diaphragm-muscle, compared with day 45 in lung tissue; the greatest differences (increases in carbonyl levels were observed on day 7 in both tissue types; and sulfhydryl levels were lower, in both tissue types, at all time points. In lung tissue and diaphragm muscle, p-AMPK expression exhibited behavior similar to that of TBARS. Expression of p-mTOR was higher than the control value on days 7 and 15 in lung tissue, as it was on day 45 in diaphragm muscle. CONCLUSION: Our data demonstrate that CS exposure produces oxidative damage, not only in lung tissue but also (primarily in muscle tissue, having an additional effect on respiratory muscle, as is frequently observed in smokers with COPD.

Method of producing the arched surfaces of diaphragm rings for large containers, especially for prestressed-concrete pressure vessels of nuclear reactors

International Nuclear Information System (INIS)

Kumpf, H.

1976-01-01

In producing arched surfaces of diaphragm rings for large containers, especially for prestressed-concrete pressure vessels for nuclear power plants, it is of advantage to manufacture these directly on the construction site. According to the invention the, at first level, diaphragm ring is put on the predetermined place, sectionally pressed against and shaped by a shaping tool - with a profiled supporting ring as a counter-acting tool - and afterwards welded together with the annular wall sections of the large container along the shaped parts. The manufacture of single and double configurations of diaphragm rings is described. It is of advantage if shaping and mounting position coincide. (UWI) [de

Opaque iris claw lens in a phakic eye to correct acquired diplopia

NARCIS (Netherlands)

Landesz, M; Worst, JGF; Rij, GV; Houtman, WA

1997-01-01

A 25-year-old man had diplopia caused by abducens nerve paresis on both sides after cranial injury. Because of the patient's reports of persistent diplopia after surgical correction, a specially manufactured, tinted iris claw lens was implanted in the left eye, with the crystalline lens in situ.

Clinical and patient-reported outcomes of bilateral implantation of a +2.5 diopter multifocal intraocular lens.

Science.gov (United States)

Maxwell, Andrew; Holland, Edward; Cibik, Lisa; Fakadej, Anna; Foster, Gary; Grosinger, Les; Moyes, Andrew; Nielsen, Stephen; Silverstein, Steven; Toyos, Melissa; Weinstein, Arthur; Hartzell, Scott

2017-01-01

To assess the effectiveness and safety of a multifocal intraocular lens (IOL) with +2.5 diopter (D) additional power compared with a monofocal IOL. Fifteen sites in the United States. Prospective randomized patient- and observer-masked clinical trial. Randomized patients received multifocal or monofocal IOLs bilaterally. Visual acuity (33 cm, 40 cm, 53 cm, 60 cm, 4 m) was measured; safety was assessed through adverse event rates. Patient-reported visual outcomes were evaluated using the Visual Tasks questionnaire. The frequency and severity of visual disturbances were evaluated using the Assessment of Photic Phenomena and Lens EffectS questionnaire. The multifocal IOL (n = 155) provided better corrected distance visual acuity at 53 cm than the monofocal IOL (n = 165) (0.322 versus 0.512 logMAR; between-group difference, -0.190 logMAR; P < .0001) and 40 cm but not at 4 m. Ocular adverse event rates were less than 3.84% in both groups. Serious adverse event rates were comparable between the 2 IOL types. Patients with multifocal IOLs reported less difficulty with near tasks (with and without correction) and intermediate tasks (without correction). Difficulty with extended-intermediate and distance tasks was similar between groups. The most frequently reported self-rated severe phenomena were halos, starbursts, and glare. Most patients (monofocal ≥72%; multifocal ≥73%) reported never experiencing blurred, distorted, or double vision. The +2.5 D multifocal IOL provided better vision at 40 cm and 53 cm and similar vision at 4 m compared with the monofocal IOL. Safety profiles and visual phenomena were comparable between groups. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

A high excitation magnetic quadrupole lens quadruplet incorporating a single octupole lens for a low spherical aberration probe forming lens system

Science.gov (United States)

Dou, Yanxin; Jamieson, David N.; Liu, Jianli; Li, Liyi

2018-03-01

This paper describes the design of a new probe forming lens system consisting of a high excitation magnetic quadrupole lens quadruplet that incorporates a single magnetic octupole lens. This system achieves both a high demagnification and a low spherical aberration compared to conventional high excitation systems and is intended for deployment for the Harbin 300 MeV proton microprobe for applications in space science and ion beam therapy. This relative simplicity of the ion optical design to include a single octupole lens minimizes the risks associated with the constructional and operational precision usually needed for the probe forming lens system and this system could also be deployed in microprobe systems that operate with less magnetically rigid ions. The design of the new system is validated with reference to two independent ion optical computer codes.

Acanthamoeba keratitis in a non-contact lens wearer with human immunodeficiency virus

DEFF Research Database (Denmark)

Hansen, Birgitte Rønde; Kronborg, Gitte

2003-01-01

, and was treated with various topical antibiotics and steroids. 13 months after symptom onset the eye was removed owing to serious scarring of cornea and unbearable pain. Microbiological and histopathological examination of the cornea showed Acanthamoeba. In non-contact lens wearers suffering from Acanthamoeba......Acanthamoeba keratitis is potentially blinding and often associated with contact lens wearing. A human immunodeficiency virus (HIV)-positive patient, a non-contact lens wearer, presented with keratitis. She experienced a protracted course of disease, characterized by exacerbations and remissions...

Concrete Flow in Diaphragm Wall Panels : A Full-Scale In-Situ Test

NARCIS (Netherlands)

Van Dalen, J.H.; Bosch, J.W.; Broere, W.

2015-01-01

Flow processes, taking place during the concreting of diaphragm wall panels (D-wall panels), are of great importance for the quality of the wall. During this phase, the bentonite, present in the excavated trench, should be completely replaced by concrete in a controlled way. In literature several

Objective lens

Science.gov (United States)

Olczak, Eugene G. (Inventor)

2011-01-01

An objective lens and a method for using same. The objective lens has a first end, a second end, and a plurality of optical elements. The optical elements are positioned between the first end and the second end and are at least substantially symmetric about a plane centered between the first end and the second end.

Radiation exposure to the lens of the eye in temporal bone radiography

International Nuclear Information System (INIS)

Paix, D.

1980-01-01

Both the sensitivity of the eye to radiation cataract and the doses delivered to it in petrous bone examination are ill-defined. However, the following guidelines are suggested: (1) radiation cataract is unlikely to be a contraindication in patients over 50; (2) lens exposure per film when using an AP projection should be about 5m Gy; this may be reduced tenfold when tomographic movements permit the use of eye shields containing 1mm of lead; (3) projections which do not include the eyes in the direct beam should entail lens doses of 0.2m Gy or less; (4) steps should be taken to prevent the accumulated dose to the patient's lens from reaching 300m Gy per year or 15 Gy in all

Percutaneous radiofrequency ablation of hepatocellular carcinoma abutting the diaphragm and gastrointestinal tracts with the use of artificial ascites: safety and technical efficacy in 143 patients

International Nuclear Information System (INIS)

Song, Inyoung; Rhim, Hyunchul; Lim, Hyo K.; Kim, Young-sun; Choi, Dongil

2009-01-01

The purpose of this study was to assess the feasibility, safety and efficacy of radiofrequency ablation (RFA) with the use of artificial ascites for hepatocellular carcinoma (HCC) adjacent to the diaphragm and gastrointestinal tract. One hundred forty-three patients with 181 HCCs who underwent US-guided percutaneous RFA with the use of artificial ascites were retrospectively reviewed. Among the 181 HCCs, 148 HCCs were defined as problematic nodules for two major reasons: poor sonic window or possible thermal injury. We artificially induced ascites before performing RFA by dripping 5% dextrose in a water solution. We assessed the technical success of introducing artificial ascites, technical feasibility of the use of artificial ascites and complications. The technical success rate, as well as the primary and secondary technique success rate, was assessed by regular follow-up CT examinations. RFA with artificial ascites was successfully achieved in 130 of 143 patients. The primary technique effectiveness was 85.3%. During follow-up (mean, 20.4 months), remote intrahepatic recurrence occurred in 49 patients and local tumor progression occurred in 15 patients. Three (2.1%) of the 143 patients experienced major complications (hemoperitoneum, lobar infarction and biloma) related to the RFA procedure. The use of artificial ascites is a simple and useful technique to minimize collateral thermal injury and to improve the sonic window. (orig.)

Contact Lens Care

Science.gov (United States)

... Consumers Consumer Information by Audience For Women Contact Lens Care Share Tweet Linkedin Pin it More sharing ... www.fda.gov/medwatch Learn More about Contact Lens Care Other Tips on Contact Lenses Decorative Contact ...

Intraocular pressure measurement over soft contact lens by rebound tonometer: a comparative study.

Science.gov (United States)

Nacaroglu, Senay Asik; Un, Emine Seker; Ersoz, Mehmet Giray; Tasci, Yelda

2015-01-01

To evaluate the intraocular pressure (IOP) measurements by Icare rebound tonometer over a contact lens in comparison with Goldmann applanation tonometry (GAT). Fifty patients using contact lens were included in this study. One of the eyes of the patients was selected randomly and their IOP were measured by rebound tonometer with and without contact lens (RTCL, RT respectively) and by GAT, as well as their central corneal thickness (CCT) by optical pachymeter. The results of both methods were compared by correlation analysis, general linear method repeated measure and Bland-Altman analysis. Mean IOP values measured by RTCL, RT and GAT were 15.68±3.7, 14.50±3.4 and 14.16±2.8 (Pcontact lens by rebound tonometer was found to be higher than what was measured by GAT. Although this difference is statistically significant, it may be clinically negligible in the normal population.

Late in-the-bag intraocular lens dislocation in patients with uveitis.

Science.gov (United States)

Steeples, Laura R; Jones, Nicholas P

2015-09-01

Late in-the-bag intraocular lens (IOL) dislocation is an unusual complication of cataract surgery, being strongly associated with pseudoexfoliation, less so with previous vitreoretinal surgery, myopia and uveitis. We present the clinical features, management and outcomes of late spontaneous IOL dislocation in a series of patients with uveitis. A retrospective case series of IOL dislocation affecting patients in the Manchester Uveitis Clinic, UK. The uveitis diagnosis, IOL type, presentation and management are discussed. Six patients from out of 1056 undergoing cataract surgery (0.57%) were affected. Uveitis was the only identified risk factor for IOL dislocation, which occurred a mean 10.3 years following uncomplicated cataract surgery by phakoemulsification with endocapsular IOL implantation. The dislocation was in-the-bag in all six cases. Two patients presented with the IOL in the anterior chamber, and required removal of the IOL-bag complex, and are using aphakic refractive correction. Two patients with inferior IOL subluxation have been managed conservatively. Two patients underwent pars plana vitrectomy with sutureless scleral fixation of the existing IOL in one case, and IOL exchange with a scleral sutured IOL in the other. IOL dislocation is an uncommon late complication in patients with uveitis. Conservative management is appropriate in patients with tolerable symptoms, or in those with difficult uveitis. Otherwise, fixation of the existing IOL, or removal and implantation of a secondary IOL, may be necessary. Angle-supported, or iris-enclaved IOLs, are not of proven safety in this patient group; scleral-fixated posterior chamber IOLs are the favoured approach in our service. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Delayed diagnosis of homocystinuria presenting as bilateral congenital lens subluxation

Directory of Open Access Journals (Sweden)

Jelić-Vuković Marija

2017-01-01

Full Text Available Introduction. Homocystinuria is an autosomal recessively inherited defect leading to hyperhomocysteinemia and associated with ocular manifestations, mainly myopia and ectopia lentis. Case outline. A 26-year-old male with secondary glaucoma due to bilateral lens subluxation was admitted to the Department of vitreoretinal surgery. Horizontal nystagmus, bilateral lens subluxation, and bilateral amblyopia were first discovered at the age of three years. Preoperative laboratory workup revealed elevated levels of homocysteine. Bilateral pars plana lensectomy and vitrectomy followed by a sulcus fixation of the intraocular lens (ALCON MA60 Acrysof IOL were performed. The patient was prescribed folic acid, methionine, and pyridoxine, and was urged to maintain a methionine-low diet. After a bilateral lensectomy and sulcus fixation of the intraocular lens and a methionine restriction therapy combined with vitamin B6, B9, and B12 supplementation, his condition improved greatly. Conclusion. In this report of a rare case we emphasize the importance of examining differential diagnoses of lens subluxation, since early intervention can prevent serious complications.

Design recommendations for the optimized continuity diaphragm for prestressed concrete bulb-T beams.

Science.gov (United States)

2008-01-01

This research focused on prestressed concrete bulb-T (PCBT) beams made composite with a cast-in-place concrete deck and continuous over several spans through the use of continuity diaphragms. The current design procedure in AASHTO states that a conti...

Changes in blood pressure and sleep duration in patients with blue light-blocking/yellow-tinted intraocular lens (CHUKYO study).

Science.gov (United States)

Ichikawa, Kazuo

2014-07-01

Blood pressure and sleep duration may be influenced by retinal light exposure. Cataracts may exert such an influence by decreasing the transparency of the crystalline lens. A large-scale clinical study was conducted to examine changes in blood pressure and sleep duration after intraocular lens (IOL) implantation during cataract surgery and to investigate how different types of IOL influence the degree of these effects. Using a questionnaire, we collected information, including blood pressure measurement and sleep duration, from 1367 patients (1367 eyes) before IOL implantation, 1 week after IOL implantation and 1 month after IOL implantation. Systolic and diastolic blood pressures were significantly decreased in the total patient group after implantation. The decrease in systolic blood pressure 1 month after implantation was significantly more in patients who received a yellow-tinted IOL than it was in those who received an ultraviolet (UV) light-filtering IOL. The post-implantation sleep duration, including naps, became shorter in patients who had slept too much and became longer in those who had slept too little before IOL implantation. Our observations suggest that a yellow-tinted IOL is better for patients with high blood pressure than a UV light-filtering IOL. Furthermore, the yellow-tinted IOL is as good as the UV light-filtering IOL for improving sleep duration. A pale yellow-tinted IOL is likely to be superior to a moderate yellow-tinted IOL in terms of allowing patients to discriminate different colors. Thus, the pale yellow-tinted IOL appears to be better for patients than the UV light-filtering IOL and the moderate yellow-tinted IOL.

Oxygen transport through soft contact lens and cornea: Lens characterization and metabolic modeling

Science.gov (United States)

Chhabra, Mahendra

The human cornea requires oxygen to sustain metabolic processes critical for its normal functioning. Any restriction to corneal oxygen supply from the external environment (e.g., by wearing a low oxygen-permeability contact lens) can lead to hypoxia, which may cause corneal edema (swelling), limbal hyperemia, neovascularization, and corneal acidosis. The need for adequate oxygen to the cornea is a major driving force for research and development of hypertransmissible soft contact lenses (SCLs). Currently, there is no standard technique for measuring oxygen permeability (Dk) of hypertransmissible silicone-hydrogel SCLs. In this work, an electrochemistry-based polarographic apparatus was designed, built, and operated to measure oxygen permeability in hypertransmissible SCLs. Unlike conventional methods where a range of lens thickness is needed for determining oxygen permeabilities of SCLs, this apparatus requires only a single lens thickness. The single-lens permeameter provides a reliable, efficient, and economic tool for measuring oxygen permeabilities of commercial hypertransmissible SCLs. The single-lens permeameter measures not only the product Dk, but, following modification, it measures separately diffusivity, D, and solubility, k, of oxygen in hypertransmissible SCLs. These properties are critical for designing better lens materials that ensure sufficient oxygen supply to the cornea. Metabolism of oxygen in the cornea is influenced by contact-lens-induced hypoxia, diseases such as diabetes, surgery, and drug treatment, Thus, estimation of the in-vivo corneal oxygen consumption rate is essential for gauging adequate oxygen supply to the cornea. Therefore, we have developed an unsteady-state reactive-diffusion model for the cornea-contact-lens system to determine in-vivo human corneal oxygen-consumption rate. Finally, a metabolic model was developed to determine the relation between contact-lens oxygen transmissibility (Dk/L) and corneal oxygen deficiency. A

Effects of Processing Parameters on the Forming Quality of C-Shaped Thermosetting Composite Laminates in Hot Diaphragm Forming Process

Science.gov (United States)

Bian, X. X.; Gu, Y. Z.; Sun, J.; Li, M.; Liu, W. P.; Zhang, Z. G.

2013-10-01

In this study, the effects of processing temperature and vacuum applying rate on the forming quality of C-shaped carbon fiber reinforced epoxy resin matrix composite laminates during hot diaphragm forming process were investigated. C-shaped prepreg preforms were produced using a home-made hot diaphragm forming equipment. The thickness variations of the preforms and the manufacturing defects after diaphragm forming process, including fiber wrinkling and voids, were evaluated to understand the forming mechanism. Furthermore, both interlaminar slipping friction and compaction behavior of the prepreg stacks were experimentally analyzed for showing the importance of the processing parameters. In addition, autoclave processing was used to cure the C-shaped preforms to investigate the changes of the defects before and after cure process. The results show that the C-shaped prepreg preforms with good forming quality can be achieved through increasing processing temperature and reducing vacuum applying rate, which obviously promote prepreg interlaminar slipping process. The process temperature and forming rate in hot diaphragm forming process strongly influence prepreg interply frictional force, and the maximum interlaminar frictional force can be taken as a key parameter for processing parameter optimization. Autoclave process is effective in eliminating voids in the preforms and can alleviate fiber wrinkles to a certain extent.

Refractive lens exchange in younger and older presbyopes: comparison of complication rates, 3 months clinical and patient-reported outcomes.

Science.gov (United States)

Schallhorn, Steven C; Schallhorn, Julie M; Pelouskova, Martina; Venter, Jan A; Hettinger, Keith A; Hannan, Stephen J; Teenan, David

2017-01-01

To compare refractive and visual outcomes, patient satisfaction, and complication rates among different age categories of patients who underwent refractive lens exchange (RLE). A stratified, simple random sample of patients matched on preoperative sphere and cylinder was selected for four age categories: 45-49 years (group A), 50-54 years (group B), 55-59 years (group C), and 60-65 years (group D). Each group contained 320 patients. All patients underwent RLE with a multifocal intraocular lens at least in one eye. Three months postoperative refractive/visual and patient-reported outcomes are presented. The percentage of patients that achieved binocular uncorrected distance visual acuity 20/20 or better was 91.6% (group A), 93.8% (group B), 91.6% (group C), 88.8% (group D), P =0.16. Binocularly, 80.0% of patients in group A, 84.7% in group B, 78.9% in group C, and 77.8% in group D achieved 20/30 or better uncorrected near visual acuity ( P =0.13). The proportion of eyes within 0.50 D of emmetropia was 84.4% in group A, 86.8% in group B, 85.7% in group C, and 85.8% in group D ( P =0.67). There was no statistically significant difference in postoperative satisfaction, visual phenomena, dry eye symptoms, distance or near vision activities. Apart from higher rate of iritis in the age group 50-55 years, there was no statistically significant difference in postoperative complication rates. RLE can be safely performed in younger as well as older presbyopes. No significant difference was found in clinical or patient-reported outcomes.

Crystalline lens power and refractive error.

Science.gov (United States)

Iribarren, Rafael; Morgan, Ian G; Nangia, Vinay; Jonas, Jost B

2012-02-01

To study the relationships between the refractive power of the crystalline lens, overall refractive error of the eye, and degree of nuclear cataract. All phakic participants of the population-based Central India Eye and Medical Study with an age of 50+ years were included. Calculation of the refractive lens power was based on distance noncycloplegic refractive error, corneal refractive power, anterior chamber depth, lens thickness, and axial length according to Bennett's formula. The study included 1885 subjects. Mean refractive lens power was 25.5 ± 3.0 D (range, 13.9-36.6). After adjustment for age and sex, the standardized correlation coefficients (β) of the association with the ocular refractive error were highest for crystalline lens power (β = -0.41; P lens opacity grade (β = -0.42; P lens power (β = -0.95), lower corneal refractive power (β = -0.76), higher lens thickness (β = 0.30), deeper anterior chamber (β = 0.28), and less marked nuclear lens opacity (β = -0.05). Lens thickness was significantly lower in eyes with greater nuclear opacity. Variations in refractive error in adults aged 50+ years were mostly influenced by variations in axial length and in crystalline lens refractive power, followed by variations in corneal refractive power, and, to a minor degree, by variations in lens thickness and anterior chamber depth.

Comparative morphology of the diaphragm of white tufted-ear marmoset and the white-fronted marmoset

Directory of Open Access Journals (Sweden)

Thais Borges Lessa

2012-03-01

Full Text Available The marmosets of the Callithrix genus have a great importance in the research field, not only for its occurrence in the ecosystems of South America and Central America, but also because of its small size and easy management. This study aimed to characterize the ultrastructure of the diaphragm of four adult animals of the C. jacchus species and four animals of the C. geoffroyi species that died from natural causes. Diaphragms were collected, dissected, and fixed in 10% formaldehyde and analyzed through scanning electron microscopy. It was observed the presence of an external membrane of connective tissue, with cylindrical muscle fibers arranged in rows perpendicular to the longitudinal axis and grouped into fascicles. In C. jacchus it was observed a discontinuous and linear fibers’ architecture, resulting in a score of 7 and 8 fascicles for male and female, respectively. In C. geoffroyi the fiber had a continuous shape, but also linear, yielding a total of 9 and 6 fascicles for male and female, respectively. The architecture of muscle fibers and the count of fascicles of the coastal face of the diaphragm suggest differences between the species C. geoffroyi and C. jacchus and between males and females, intra- and interspecies.

Acute gastric volvulus secondary to eventration of the diaphragm in a child

Directory of Open Access Journals (Sweden)

Singal A

2006-01-01

Full Text Available We report an 18-month-old boy who presented with acute organoaxial volvulus of stomach secondary to eventration of diaphragm. Clinically, the child exhibited classical triad of epigastric distension, unproductive retching and inability to pass a nasogastric tube. Successful operative management is presented and relevant literature is discussed.

Diaphragm pacing and noninvasive respiratory management of amyotrophic lateral sclerosis/motor neuron disease.

Science.gov (United States)

Mahajan, Kedar R; Bach, John Robert; Saporito, Lou; Perez, Nick

2012-12-01

Although it is known that continuous noninvasive ventilation (CNIV) can prolong life in amyotrophic lateral sclerosis/motor neuron disease (ALS/MND), in this study we explore similar claims for diaphragm pacing (DP). NIV and DP users' vital capacities (VCs) over time and duration of NIV and CNIV dependence were analyzed for 354 non-DP and 8 DP ALS/MND patients. Patients had a higher rate of monthly VC decline before NIV use (5.1 ± 7.6%) than during NIV use (2.5 ± 3.6%) (P NIV for 19.9 ± 27.6 months until tracheostomy/death, whereas 113 others used it for 10.9 ± 10.5 months until CNIV dependence for another 12.8 ± 16.2 months. After placement, 7 DP users were CNIV dependent in 8.0 ± 7.0 months, whereas 6 underwent tracheostomy/died in 18.2 ± 13.7 months. CNIV prolonged the survival of 113 of the 354 non-DP and 6 DP ALS/MND patients by 12.8 and 10.2 months, respectively. DP provided no benefit on VC or mechanical ventilation-free survival. Copyright © 2012 Wiley Periodicals, Inc.

Electrical activity of the diaphragm during nCPAP and high flow nasal cannula

NARCIS (Netherlands)

de Waal, C. G.; Hutten, G. J.; Kraaijenga, J. V.; de Jongh, F. H.; van Kaam, A. H.

2017-01-01

Objective To determine if the electrical activity of the diaphragm, as measure of neural respiratory drive and breathing effort, changes over time in preterm infants transitioned from nasal continuous positive airway pressure (nCPAP) to high flow nasal cannula (HFNC). Design Prospective

Advanced pigment dispersion glaucoma secondary to phakic intraocular collamer lens implant

Directory of Open Access Journals (Sweden)

Clara Ye

2018-06-01

Full Text Available Purpose: We report a case of pigment dispersion glaucoma secondary to uncomplicated phakic intraocular collamer lens (ICL (Visian ICL™, Staar Inc., Monrovia, CA implant that resulted in advanced visual field loss. Observations: A 50-year-old man presented for routine follow-up status post bilateral phakic intraocular collamer lens (ICL placement 8 years earlier. He was incidentally found to have a decline in visual acuity from an anterior subcapsular cataract and elevated intraocular pressure (IOP in the left eye. There were signs of pigment dispersion and no evidence of angle closure. Diffuse optic nerve thinning was consistent with advanced glaucomatous visual field defects. Pigment dispersion was also present in the patient's right eye, but without elevated IOP or visual field defects. The patient was treated with topical glaucoma medications and the phakic ICL in the left eye was removed concurrently with cataract surgery to prevent further visual field loss. Conclusions and importance: Pigment dispersion glaucoma is a serious adverse outcome after phakic ICL implantation and regular post-operative monitoring may prevent advanced visual field loss. Keywords: Phakic intraocular lens, Intraocular collamer lens, Pigment dispersion, Glaucoma

Structure of diaphragm floor of reactor container, construction module and construction method thereof

International Nuclear Information System (INIS)

Hasegawa, Hiroshi; Oikawa, Tadaaki; Ushiroda, Koichi; Matsuura, Tadashi; Komaru, Toshimi; Nemoto, Yoichi; Makita, Tatsuo; Maezawa, Sumito.

1998-01-01

A diaphragm floor of a reactor container has a structure comprising iron beams buried in concretes and connection members connecting the iron beams and liners, in which the liners are supported by the iron beams, and the load of the iron reinforced concretes when formed on the liner is supported by the iron beams thereby enabling to construct a diaphragm floor with no or reduced amount of temporary support members. As a result, the construction operation can be promoted by reducing the amount of the temporary support members or making the removing operation of the temporary support members unnecessary. The concrete layer comprises at least two upper and lower layers of a firstly formed concrete layer and a subsequently formed concrete layer, and the iron beams have such a strength capable of enduring the load applied when the firstly formed concrete is placed. (N.H.)

Characteristics of the thick, compound refractive lens

International Nuclear Information System (INIS)

Pantell, Richard H.; Feinstein, Joseph; Beguiristain, H. Raul; Piestrup, Melvin A.; Gary, Charles K.; Cremer, Jay T.

2003-01-01

A compound refractive lens (CRL), consisting of a series of N closely spaced lens elements each of which contributes a small fraction of the total focusing, can be used to focus x rays or neutrons. The thickness of a CRL can be comparable to its focal length, whereupon a thick-lens analysis must be performed. In contrast with the conventional optical lens, where the ray inside the lens follows a straight line, the ray inside the CRL is continually changing direction because of the multiple refracting surfaces. Thus the matrix representation for the thick CRL is quite different from that for the thick optical lens. Principal planes can be defined such that the thick-lens matrix can be converted to that of a thin lens. For a thick lens the focal length is greater than for a thin lens with the same lens curvature, but this lengthening effect is less for the CRL than for the conventional optical lens

Developing a new ultrasonic method to assess diaphragm movement and comparing the accuracy with existing methods

DEFF Research Database (Denmark)

Helbo Skaarup, Søren; Løkke, Anders; Laursen, Christian

2017-01-01

Introduction: Diaphragm is the most important respiratory muscle. Movement can be evaluated with ultrasound. Currently two different methods are used, M-mode and B-mode. However, diaphragm movement is complex.Aim: We hypothesized that the two existing methods are imprecise as they only measure...... film clips independently to assess inter-rater variability.Results: We found a linear correlation between FVC and diaphragmatic movement. M-mode had Pearson r=0.84 (95%CI 0.76-0.89), B-mode had r=0.68 (95%CI 0.55-0.79) and Area-measurement had r=0.84 (95%CI 0.77-0.90). Inter-rater agreement was r=0...

Comparison on the visual quality after different multifocal lens implantation in cataract patients

Directory of Open Access Journals (Sweden)

Si-Meng Qu

2018-02-01

Full Text Available AIM: To compare the visual quality after different multifocal lens(MIOLimplantation in cataract patients. METHODS:Totally 78 cases(78 eyesof cataract patients who receiving phacoemulsification and implantation of different MIOL were enrolled from February 2016 to June 2017 in our hospital. According to the different type of implanted MIOL, the 78 cases(78 eyeswere divided Group A, B and C, each group was 26 cases(26 eyes. Patients in the Group A were implanted regional refraction MIOL SBL-3; patients in the Group B implanted step progressive diffraction MIOL SN6AD1; patients in the Group C implanted all-optical plane diffraction MIOL Tecnis ZMB00. The visual acuity, contrast sensitivity, defocus testing, contrast visual acuity and satisfaction of visual quality were compared in 3 groups at postoperative 3mo. RESULTS: There was no statistically significant difference in postoperative adverse reactions between the three groups(P>0.05. There was statistical difference in uncorrected intermediate visual acuity, uncorrected near visual acuity, distance-corrected intermediate visual acuity and distance-corrected near visual acuity in 3 groups(PPPPPPPPPCONCLUSION:The region refraction MIOL SBL-3 not only could provide better distant, intermediate and near visual acuity, but also could provide better contrast sensitivity and contrast visual acuity, thereby greatly increase visual quality satisfaction.

DISSECTING THE GRAVITATIONAL LENS B1608+656. I. LENS POTENTIAL RECONSTRUCTION

NARCIS (Netherlands)

Suyu, S. H.; Marshall, P. J.; Blandford, R. D.; Fassnacht, C. D.; Koopmans, L. V. E.; McKean, J. P.; Treu, T.

2009-01-01

Strong gravitational lensing is a powerful technique for probing galaxy mass distributions and for measuring cosmological parameters. Lens systems with extended source-intensity distributions are particularly useful for this purpose since they provide additional constraints on the lens potential (

Accidental injections of dexamethasone intravitreal implant (Ozurdex) into the crystalline lens.

Science.gov (United States)

Coca-Robinot, Javier; Casco-Silva, Bruno; Armadá-Maresca, Felix; García-Martínez, Jesús

2014-01-01

To describe the side effects and management after inadvertent injection of a dexamethasone implant (Ozurdex) into the crystalline lens. Two case reports. Two patients with macular edema due to unilateral retinal vein occlusion were scheduled for an intravitreal injection of Ozurdex. During the procedure, the implant was accidentally injected into the crystalline lens. Both patients developed cataracts during the course of several weeks and in both there was an intraocular pressure (IOP) increase, which required treatment with topical hypotensives. Macular edema improved only slightly. Cataract surgery with uneventful removal of the implant was performed 3 (case 1) and 6 months (case 2) after the injection. After inadvertent injection of Ozurdex into the crystalline lens, cataract surgery with removal of the implant should be performed as soon as possible in order to avoid IOP increase and so that the underlying condition may be treated adequately.

Intraocular lens fabrication

Energy Technology Data Exchange (ETDEWEB)

Salazar, Mike A. (Albuquerque, NM); Foreman, Larry R. (Los Alamos, NM)

1997-01-01

This invention describes a method for fabricating an intraocular lens made rom clear Teflon.TM., Mylar.TM., or other thermoplastic material having a thickness of about 0.025 millimeters. These plastic materials are thermoformable and biocompatable with the human eye. The two shaped lenses are bonded together with a variety of procedures which may include thermosetting and solvent based adhesives, laser and impulse welding, and ultrasonic bonding. The fill tube, which is used to inject a refractive filling material is formed with the lens so as not to damage the lens shape. A hypodermic tube may be included inside the fill tube.

Documentation of diaphragmal paralysis with digital subtraction techniques. Dokumentation von Zwerchfellparesen mit digitaler Subtraktionstechnik

Energy Technology Data Exchange (ETDEWEB)

Waggershauser, T. (Muenchen Univ. (Germany). Radiologische Klinik und Poliklinik Muenchen Univ. (Germany). Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenkranke); Buente, E. (Muenchen Univ. (Germany). Radiologische Klinik und Poliklinik Muenchen Univ. (Germany). Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenkranke); Kohz, P. (Muenchen Univ. (Germany). Radiologische Klinik und Poliklinik Muenchen Univ. (Germany). Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenkranke); Fink, U. (Muenchen Univ. (Germany). Radiologische Klinik und Poliklinik Muenchen Univ. (Germany). Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenkranke)

1992-01-01

The causative factors for a paresis of the diaphragm are primarily subsequent to operations on lesions of the phrenic nerve or on such mediastinal tumors as lyphomas which result in compression or infiltration of the nerves. (orig.)

Clinical Presentation and Microbial Analyses of Contact Lens Keratitis; an Epidemiologic Study

Directory of Open Access Journals (Sweden)

Seyed Ahmad Rasoulinejad

2014-09-01

Full Text Available Introduction: Microbial keratitis is an infective process of the cornea with a potentially and serious visual impairments. Contact lenses are a major cause of microbial keratitis in the developed countries especially among young people. Therefore, the purpose of the present study was to evaluate the frequency and microbiological characteristic of CLK in patients referred to the emergency department (ED of teaching hospitals, Babol, Iran. Methods: This is a cross-sectional study of all patients with contact lens induced corneal ulcers admitted to the teaching hospitals of Babol, Iran, from 2011- 2013. An ophthalmologist examined patients with the slit-lamp and clinical features of them were noted (including pain, redness, foreign body sensation, chemosis, epiphora, blurred vision, discomfort, photophobia, discharge, ocular redness and swelling. All suspected infectious corneal ulcers were scraped for microbial culture and two slides were prepared. Data were analyzed using SPSS software, version 18.0. Results: A total of 14 patients (17 eyes were recruited into the study (100% female. The patients’ age ranged from 16-37 years old (mean age 21.58±7.23 years. The most prevalent observed clinical signs were pain and redness. Three samples reported as sterile. The most common isolated causative organism was pseudomonas aeroginosa (78.6%, Staphylococcus aureus 14.3%, and enterobacter 7.1%, respectively. Treatment outcome was excellent in 23.5%, good in 47.1%, and poor in 29.4% of cases. Conclusion: Improper lens wear and care as well as the lack of awareness about the importance of aftercare visits have been identified as potential risk factors for the corneal ulcer among contact lens wearers. Training and increasing the awareness of adequate lens care and disinfection practices, consulting with an ophthalmologist, and frequent replacement of contact lens storage cases would greatly help reducing the risk of microbial keratitis.

Clinical observation of capsular tension ring implantation in congenital lens subluxation treating by phacoemulsification

OpenAIRE

Liang-Nan Sun; Bai-Jun Li; Yuan-Fei Zhu; Xin-Hua Liu

2017-01-01

AIM: To evaluate the clinical results of capsular tension ring(CTR)implantation in phacoemulsification for eyes with congenital lens subluxation. METHODS: This study comprised 18 patients(31 eyes)with congenital ectopia lentis. All patients received phacoemulsification with CTR and intraocular lens(IOL)implantation. Visual acuity before and after surgery were examined. IOL decentration were measured with Image-Pro Plus image processing software. The complications were also recorded preoperati...

Ocular distribution of antioxidant enzyme paraoxonase & its alteration in cataractous lens & diabetic retina

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Subramaniam Rajesh Bharathidevi

2017-01-01

Interpretation & conclusions: Distribution of PON enzyme and its activity in ocular tissues is reported here. The study revealed maximal PON activity in lens and retina, which are prone to higher oxidative stress. Differential activities of PON were observed in the lens and retinal tissues from cataractous and diabetic patients, respectively.

Aphakia correction with retropupillary fixated iris-claw lens (Artisan – long-term results

Directory of Open Access Journals (Sweden)

Schallenberg M

2013-12-01

Full Text Available Maurice Schallenberg,1,2 Dirk Dekowski,1 Angela Hahn,1 Thomas Laube,1,3 Klaus-Peter Steuhl,1 Daniel Meller11Department of Ophthalmology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany; 2HELIOS Klinikum Wuppertal, Wuppertal, Germany; 3Zentrum für Augenheilkunde PD Dr Laube, Düsseldorf, GermanyPurpose: To evaluate the technique, safety, and efficacy of the retropupillary implantation of iris-claw intraocular lenses in a long-term follow-up study.Patients and methods: This retrospective study included 31 eyes of 31 patients who underwent an Artisan aphakic intraocular lens implantation between January 2006 and February 2011 at the University Hospital Essen, Essen, Germany and at the Zentrum für Augenheilkunde PD Dr Laube, Düsseldorf, Germany. Preoperative data collected included demographics, etiology of aphakia, previous surgeries, preoperative eye pathology, intraocular pressure, clinical signs of endothelial cell loss, and best corrected visual acuity. Operative data and postoperative outcomes included the best corrected visual acuity, lens position, intraocular pressure, pigment dispersion, clinical signs of endothelial cell loss, development of macular edema, and other complications.Results: Thirty-one patients were included. The mean follow-up was 25.2 months (range: 4–48 months. The mean best corrected visual acuity postoperatively was 0.64 logarithm of the minimum angle of resolution (logMAR and varied from 0 logMAR to 3 logMAR. Some patients had a low visual acuity preoperatively because of preoperative eye pathologies. In 22 patients the visual acuity improved, in two patients the visual acuity remained unchanged, and seven patients showed a decreased visual acuity. Complications were peaked pupils (n=10 and retinal detachment in one case. Four patients showed an iris atrophy and high intraocular pressure was observed only in one patient. Subluxation of the intraocular lens, endothelial cell loss, and

Straylight Measurements in Contact Lens Wear

NARCIS (Netherlands)

van der Meulen, Ivanka J. E.; Engelbrecht, Leonore A.; van Vliet, Johannes M. J.; Lapid-Gortzak, Ruth; Nieuwendaal, Carla P.; Mourits, Maarten P.; Schlingemann, Reinier O.; van den Berg, Thomas J. T. P.

2010-01-01

Purpose: (1) To quantify the effect of contact lens wear on straylight in rigid and soft contact lens wearers and (2) to relate findings to morphological changes and subjective complaints. Methods: Straylight was measured using the Oculus C-Quant during contact lens wear and after contact lens

Food and Drug Administration study update. One-year results from 671 patients with the 3M multifocal intraocular lens.

Science.gov (United States)

Lindstrom, R L

1993-01-01

The clinical evaluation of the Food and Drug Administration study of the 3M diffractive multifocal intraocular lens (IOL) is presented here to demonstrate the results of 1-year postoperative data accumulated for 671 patients, the first of whom received the implant in 1987. Patients were selected for study if they had absence of preoperative pathology, were at least 60 years of age, and had a reasonable postoperative prognosis. Extensive evaluations took place at 4 to 6 months and 12 to 14 months after surgery, including five different visual acuity measurements and contrast sensitivity. All testing was completed on both eyes. Data from the fellow eye served as a control when implanted with a monofocal IOL. Overall uncorrected distance visual acuity at 1 year after surgery shows 57% patients with 20/40 or better acuity. In this same group, 78% achieved J3 or better near vision, which improved to 82% in the best case group. Uncorrected visual acuity of 20/40 or better and J3 or better was achieved by 50% of best case multifocal IOL patients, compared with 26% of the monofocal best case comparison group. Measurements of contrast sensitivity consistently document a small loss, which is considered clinically insignificant. Statistical analysis of satisfaction ratings shows that predictors of satisfaction include uncorrected distance acuity, final near acuity, and fellow eye spherical equivalent. This multifocal lens appears to work very well for most patients, with more than half having functional uncorrected distance and near vision. The study showed several considerations that are important for optimizing clinical performance and patient satisfaction: patient selection, realistic expectations, accurate biometry, and adequate control of surgical procedures.

Quadrupole magnetic lens

International Nuclear Information System (INIS)

Piskunov, V.A.

1981-01-01

The following connection of windings of electromagnet is suggested for simplification of the design of qUadrupole magnetic lens intended for use in radiotechnical and electron-optical devices. The mentioned windings are connected with each other by a bridge scheme and the variable resistors are switched in its diagonals in the lens containing four electromagnet with windings connected with two variable resistors the mobile contacts of which are connected with a direct current source. Current redistribution between left windings and right windings takes place at shift of mobile contact of variable resistor, and current redistribution between upper and low coils of electromagnets takes place at shifting mobile contact of the other variable resistor. In this case smooth and independent electron-optical misalignment of lens by two mutually perpendicular directions proceeds. Use of the given design of the lens in the oscillograph permits to use printing assembly for alignment plate and to reduce the number of connections at the expense of decreasing the number of resistors

Pseudomonas aeruginosa Survival at Posterior Contact Lens Surfaces after Daily Wear

Science.gov (United States)

Wu, Yvonne T.; Zhu, Lucia S.; Tam, K. P. Connie; Evans, David J.; Fleiszig, Suzanne M. J.

2015-01-01

Purpose Pseudomonas aeruginosa keratitis is a sight-threatening complication of contact lens wear, yet mechanisms by which lenses predispose to infection remain unclear. Here, we tested the hypothesis that tear fluid at the posterior contact lens surface can lose antimicrobial activity over time during lens wear. Methods Daily disposable lenses were worn for 1, 2, 4, 6 or 8 h immediately after removal from their packaging, or after presoaking in sterile saline for 2 days to remove packaging solution. Unworn lenses were also tested, some coated in tears “aged” in vitro for 1 or 8 h. Lenses were placed anterior surface down into tryptic soy agar cradles containing gentamicin (100µg/ml) to kill bacteria already on the lens, and posterior surfaces inoculated with gentamicin-resistant P. aeruginosa for 3 h. Surviving bacteria were enumerated by viable counts of lens homogenates. Results Posterior surfaces of lenses worn by patients for 8 h supported more P. aeruginosa growth than lenses worn for only 1 h, if lenses were presoaked prior to wear (~ 2.4-fold, p = 0.01). This increase was offset if lenses were not presoaked to remove packaging solution (p = 0.04 at 2 h and 4 h). Irrespective of presoaking, lenses worn for 8 h showed more growth on their posterior surface than unworn lenses coated with tear fluid that was “aged” for 8 h vitro (~8.6-fold, presoaked, p = 0.003: ~ 5.4-fold from packaging solution, p = 0.004). Indeed, in vitro incubation did not impact tear antimicrobial activity. Conclusions This study shows that post lens tear fluid can lose antimicrobial activity over time during contact lens wear, supporting the idea that efficient tear exchange under a lens is critical for homeostasis. Additional studies are needed to determine applicability to other lens types, wearing modalities, and relevance to contact lens-related infections. PMID:25955639

Evaluation of Artisan aphakic intraocular lens in cases of pediatric aphakia with insufficient capsular support.

Science.gov (United States)

Gawdat, Ghada I; Taher, Sameh G; Salama, Marwa M; Ali, Adel A

2015-06-01

To evaluate the visual outcomes and complications after Artisan iris-claw lens implantation in aphakic children with insufficient capsular support. In this prospective, interventional noncontrolled study, aphakic eyes of consecutive patients >2 years of age with insufficient capsular support who underwent Artisan intraocular lens (IOL) implantation between June 2011 and December 2012 were followed for 1 year. Patients with anterior chamber depth IOL were included, 18 eyes with subluxated lens and 7 following trauma. The mean preoperative logMAR best-corrected visual acuity for traumatic aphakic patients was 0.95 ± 0.36; for patients with subluxation, 0.7 ± 0.26. Values improved at 1 year to 0.38 ± 0.15 (P IOL implantation for pediatric aphakia achieved a good visual outcome. Copyright © 2015 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

Contact lens surface by electron beam

International Nuclear Information System (INIS)

Shin, Jung Hyuck; Lee, Suk Ju; Hwang, Kwang Ha; Jeon Jin

2011-01-01

Contact lens materials needs good biocompatibility, high refractive index, high optical transparency, high water content etc. Surface treat method by using plasma and radiation can modify the physical and/or chemical properties of the contact lens surface. Radiation technology such as electron beam irradiation can apply to polymerization reaction and enhance the functionality of the polymer.The purpose of this study is to modify of contact lens surface by using Eb irradiation technology. Electron beam was irradiated to the contact lens surface which was synthesized thermal polymerization method and commercial contact lens to modify physical and chemical properties. Ft-IR, XP, UV-vis spectrophotometer, water content, oxygen trans-metastability were used to characterize the surface state, physicochemical, and optical property of the contact lens treated with Eb. The water content and oxygen transmissibility of the contact lens treated with Eb were increased due to increase in the hydrophilic group such as O-C=O and OH group on the contact lens surface which could be produced by possible reaction between carbon and oxygen during the Eb irradiation. All of the lenses showed the high optical transmittance above 90%. In this case of B/Es, TES, Ti contact lens, the optical transmittance decreased about 5% with increasing Eb dose in the wavelength of UV-B region. The contact lens modified by Eb irradiation could improve the physical properties of the contact lens such as water content and oxygen transmissibility

Scleral suspension pars-plana lensectomy for ectopia lentis followed by suture fixation of intraocular lens

Directory of Open Access Journals (Sweden)

Mitra Sandip

2001-01-01

Full Text Available Purpose: To describe a simple technique of scleral suspension-pars plana lensectomy (SS-PPL in acquired and congenital ectopia lentis and scleral fixation of intraocular lens (IOL. Materials and Methods: Twenty eyes of 16 patients (12 unilateral and 4 bilateral cases of "essential familial lens subluxation" aged 10-40 years (mean 25 years underwent SS-PPL with implantation of scleral fixated IOL. Indications for surgery were best-corrected visual acuity <6/18, bisection of pupil by the lens, and lens-induced glaucoma. Prerequisites for SS-PPL were, visibility of part of the lens in the pupillary area and soft lens. Results: Postoperative visual acuity ranged from 6/6 - 6/36. Lens tilt in 3 cases(15% and small decentration in 2 cases(10% were seen; however these did not seriously compromise the visual result. Scant vitreous bleeding on the first postoperative day was seen in 3 cases (15%. Conclusion: The advantages of the scleral suspension of subluxated lens prior to lensectomy include stabilization; it allows proper viewing of the lens, avoids injury to the iris and cliary body during lensectomy and reduces the possibility of dislocation of the lens.

Examination of human diaphragms for trichinosis, Hiroshima and Nagasaki

Energy Technology Data Exchange (ETDEWEB)

Gould, S E; Ozaki, Hiroyuki; Kimura, Kazuo

1961-11-30

Trichinella spiralis has been found in three species of mammals born in Hokkaido so it possibly infects other species in Japan, including man. Although examination of human diaphragms in a small series of 149 autopsies in Hiroshima and 37 autopsies in Nagasaki (by digestion, compression, and microscopic sections) failed to reveal any instance of trichinous infection, it is felt that the existence or absence of human trichinosis inJapan can be determined only by examination covering a larger series of autopsies, and performed in various parts of the country. 6 references.

Enhanced Transmissions Through Three-dimensional Cascade Sharp Waveguide Bends Using C-slit Diaphragms.

Science.gov (United States)

Yang, Rui; Hu, Bowei; Zhang, Aofang; Gao, Dongxing; Wang, Hui; Shi, Ayuan; Lei, Zhenya; Yang, Pei

2017-03-21

Transmission properties through sharp rectangular waveguide bends are investigated to determine the cut-off bending angles of the wave propagation. We show that a simple metallic diaphragm at the bending corner with properly devised sub-wavelength defect apertures of C-slits would be readily to turn on the transmissions with scarce reflections of the propagating modes, while preserving the integrity of the transmitting fields soon after the bends. In particularly, our design also demonstrates the capability of eliminating all the unwanted cavity resonant transmissions that exist in the three-dimensional cascade sharp waveguide bends, and solely let the desired signals travel along the whole passage of the waveguide. The present approach, using C-slit diaphragms to support the sharp bending behaviors of the guided waves with greatly enhanced transmissions, would be especially effective in constructing novel waveguides and pave the way for the development of more compact and miniaturized electromagnetic systems that exploit these waveguide bends.

PO2 Cycling Reduces Diaphragm Fatigue by Attenuating ROS Formation

OpenAIRE

Zuo, Li; Diaz, Philip T.; Chien, Michael T.; Roberts, William J.; Kishek, Juliana; Best, Thomas M.; Wagner, Peter D.

2014-01-01

Prolonged muscle exposure to low PO2 conditions may cause oxidative stress resulting in severe muscular injuries. We hypothesize that PO2 cycling preconditioning, which involves brief cycles of diaphragmatic muscle exposure to a low oxygen level (40 Torr) followed by a high oxygen level (550 Torr), can reduce intracellular reactive oxygen species (ROS) as well as attenuate muscle fatigue in mouse diaphragm under low PO2. Accordingly, dihydrofluorescein (a fluorescent probe) was used to monito...

Properties of the cathode lens combined with a focusing magnetic/immersion-magnetic lens

International Nuclear Information System (INIS)

Konvalina, I.; Muellerova, I.

2011-01-01

The cathode lens is an electron optical element in an emission electron microscope accelerating electrons from the sample, which serves as a source for a beam of electrons. Special application consists in using the cathode lens first for retardation of an illuminating electron beam and then for acceleration of reflected as well as secondary electrons, made in the directly imaging low energy electron microscope or in its scanning version discussed here. In order to form a real image, the cathode lens has to be combined with a focusing magnetic lens or a focusing immersion-magnetic lens, as used for objective lenses of some commercial scanning electron microscopes. These two alternatives are compared with regards to their optical properties, in particular with respect to predicted aberration coefficients and the spot size, as well as the optimum angular aperture of the primary beam. The important role of the final aperture size on the image resolution is also presented.

Investigation of piezoresistive effect in p-channel metal–oxide–semiconductor field-effect transistors fabricated on circular silicon-on-insulator diaphragms using cost-effective minimal-fab process

Science.gov (United States)

Liu, Yongxun; Tanaka, Hiroyuki; Umeyama, Norio; Koga, Kazuhiro; Khumpuang, Sommawan; Nagao, Masayoshi; Matsukawa, Takashi; Hara, Shiro

2018-06-01

P-channel metal–oxide–semiconductor field-effect transistors (PMOSFETs) with the 〈110〉 or 〈100〉 channel direction have been successfully fabricated on circular silicon-on-insulator (SOI) diaphragms using a cost-effective minimal-fab process, and their electrical characteristics have been systematically investigated before and after the SOI diaphragm formation. It was found that almost the same subthreshold slope (S-slope) and threshold voltage (V t) are observed in the fabricated PMOSFETs before and after the SOI diaphragm formation, and they are independent of the channel direction. On the other hand, significant variations in drain current were observed in the fabricated PMOSFETs with the 〈110〉 channel direction after the SOI diaphragm formation owing to the residual mechanical stress-induced piezoresistive effect. It was also confirmed that electrical characteristics of the fabricated PMOSFETs with the 〈100〉 channel direction are almost the same before and after the SOI diaphragm formation, i.e., not sensitive to the mechanical stress. Moreover, the drain current variations at different directions of mechanical stress and current flow were systematically investigated and discussed.

Exercise Prevents Diaphragm Wasting Induced by Cigarette Smoke through Modulation of Antioxidant Genes and Metalloproteinases

Directory of Open Access Journals (Sweden)

Gracielle Vieira Ramos

2018-01-01

Full Text Available Background. The present study aimed to analyze the effects of physical training on an antioxidant canonical pathway and metalloproteinases activity in diaphragm muscle in a model of cigarette smoke-induced chronic obstructive pulmonary disease (COPD. Methods. Male mice were randomized into control, smoke, exercise, and exercise + smoke groups, which were maintained in trial period of 24 weeks. Gene expression of kelch-like ECH-associated protein 1; nuclear factor erythroid-2 like 2; and heme-oxygenase1 by polymerase chain reaction was performed. Metalloproteinases 2 and 9 activities were analyzed by zymography. Exercise capacity was evaluated by treadmill exercise test before and after the protocol. Results. Aerobic training inhibited diaphragm muscle wasting induced by cigarette smoke exposure. This inhibition was associated with improved aerobic capacity in those animals that were submitted to 24 weeks of aerobic training, when compared to the control and smoke groups, which were not submitted to training. The aerobic training also downregulated the increase of matrix metalloproteinases (MMP-2 and MMP-9 and upregulated antioxidant genes, such as nuclear factor erythroid-2 like 2 (NRF2 and heme-oxygenase1 (HMOX1, in exercise + smoke group compared to smoke group. Conclusions. Treadmill aerobic training protects diaphragm muscle wasting induced by cigarette smoke exposure involving upregulation of antioxidant genes and downregulation of matrix metalloproteinases.

Where Did the Water Go?: Boyle's Law and Pressurized Diaphragm Water Tanks

Science.gov (United States)

Brimhall, James; Naga, Sundar

2007-01-01

Many homes use pressurized diaphragm tanks for storage of water pumped from an underground well. These tanks are very carefully constructed to have separate internal chambers for the storage of water and for the air that provides the pressure. One might expect that the amount of water available for use from, for example, a 50-gallon tank would be…

Clinical evaluation of direct and photosensitized ultraviolet radiation damage to the lens

International Nuclear Information System (INIS)

Hockwin, O.; Lerman, S.

1982-01-01

We are reporting a new, objective, and quantitative method for monitoring age-related molecular changes in the human ocular lens in vivo, as expressed by increases in at least two (nontryptophan) fluorescence wavelengths. These fluorescence wavelengths appear to be caused by photochemically induced changes in the lens, and they reflect the ultraviolet (UV) filtering capacity of the patients' ocular lenses. These data correlate with previously reported in vitro lens fluorescence changes that are associated with the aging process. This method will also detect alterations in lenticular fluorescence caused by photosensitized as well as direct UV radiation damage

Intraocular lens fabrication

Energy Technology Data Exchange (ETDEWEB)

Salazar, M.A.; Foreman, L.R.

1997-07-08

This invention describes a method for fabricating an intraocular lens made from clear Teflon{trademark}, Mylar{trademark}, or other thermoplastic material having a thickness of about 0.025 millimeters. These plastic materials are thermoformable and biocompatable with the human eye. The two shaped lenses are bonded together with a variety of procedures which may include thermosetting and solvent based adhesives, laser and impulse welding, and ultrasonic bonding. The fill tube, which is used to inject a refractive filling material is formed with the lens so as not to damage the lens shape. A hypodermic tube may be included inside the fill tube. 13 figs.

21 CFR 886.1375 - Bagolini lens.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Bagolini lens. 886.1375 Section 886.1375 Food and... OPHTHALMIC DEVICES Diagnostic Devices § 886.1375 Bagolini lens. (a) Identification. A Bagolini lens is a device that consists of a plane lens containing almost imperceptible striations that do not obscure...

Application of ultrasound biomicro-scopy in the planning of cataract surgery in anterior megalophthalmos

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Mohammad Ali Zare

2011-01-01

Full Text Available Anterior megalophthalmos, a rare hereditary disorder, is macrocornea (horizontal corneal diameter more than 13 mm in association with enlarged lens-iris diaphragm and ciliary ring. One of the major challenging issues in the cataract surgery of these patients is preventing intraocular lens (IOL malposition, because of probable large capsular bag. Several approaches have been selected by previous surgeons, such as, custom-made anterior chamber IOLs. In this study, we show a normal capsular bag diameter despite ciliary ring enlargement, with application of ultrasound biomicroscopy (UMB. We suggest that in cases of anterior megalophthalmos without phacodonesis, UBM could measure the actual size of the capsular bag and obviate the need for further procedures.

A Conjunctival Mass in the Deep Superior Fornix After a Long Retained Hard Contact Lens in a Patient With Keloids

NARCIS (Netherlands)

Zola, Enrica; van der Meulen, Ivanka J. E.; Lapid-Gortzak, Ruth; van Vliet, J. Mj; Nieuwendaal, Carla P.

2008-01-01

Purpose: To report a case of an upper eyelid mass induced by a rigid contact lens retained for more than 3 years in the eye of a patient with a general history of keloids and to provide a review of the literature on retained contact lenses. Methods: Case report. Results: A 45-year-old woman with an

Radiation exposure of the radiologist's eye lens during CT-guided interventions.

Science.gov (United States)

Heusch, Philipp; Kröpil, Patric; Buchbender, Christian; Aissa, Joel; Lanzman, Rotem S; Heusner, Till A; Ewen, Klaus; Antoch, Gerald; Fürst, Günther

2014-02-01

In the past decade the number of computed tomography (CT)-guided procedures performed by interventional radiologists have increased, leading to a significantly higher radiation exposure of the interventionalist's eye lens. Because of growing concern that there is a stochastic effect for the development of lens opacification, eye lens dose reduction for operators and patients should be of maximal interest. To determine the interventionalist's equivalent eye lens dose during CT-guided interventions and to relate the results to the maximum of the recommended equivalent dose limit. During 89 CT-guided interventions (e.g. biopsies, drainage procedures, etc.) measurements of eye lens' radiation doses were obtained from a dedicated dosimeter system for scattered radiation. The sensor of the personal dosimeter system was clipped onto the side of the lead glasses which was located nearest to the CT gantry. After the procedure, radiation dose (µSv), dose rate (µSv/min) and the total exposure time (s) were recorded. For all 89 interventions, the median total exposure lens dose was 3.3 µSv (range, 0.03-218.9 µSv) for a median exposure time of 26.2 s (range, 1.1-94.0 s). The median dose rate was 13.9 µSv/min (range, 1.1-335.5 µSv/min). Estimating 50-200 CT-guided interventions per year performed by one interventionalist, the median dose of the eye lens of the interventional radiologist does not exceed the maximum of the ICRP-recommended equivalent eye lens dose limit of 20 mSv per year.

The lens and cataracts.

Science.gov (United States)

Matthews, Andrew G

2004-08-01

It is conservatively estimated that some form of lens opacity is present in 5% to 7% of horses with otherwise clinically normal eyes.These opacities can range from small epicapsular remnants of the fetal vasculature to dense and extensive cataract. A cataract is defined technically as any opacity or alteration in the optical homogeneity of the lens involving one or more of the following: anterior epithelium, capsule, cortex, or nucleus. In the horse, cataracts rarely involve the entire lens structure (ie, complete cataracts) and are more usually localized to one anatomic landmark or sector of the lens. Complete cataracts are invariably associated with overt and significant visual disability. Focal or incomplete cataracts alone seldom cause any apparent visual dysfunction in affected horses,however.

Artificial pupil versus contralateral balanced contact lens fit for presbyopia correction

Directory of Open Access Journals (Sweden)

Santiago García-Lázaro

2014-04-01

Full Text Available Purpose: To assess and compare the effects of contact lens-based artificial pupil design and contralateral balanced multifocal contact lens combination (CBMCLC on visual performance. Methods: This randomized crossover study conducted at the University of Valencia, Spain included 38 presbyopic patients using an artificial pupil contact lens in the nondominant eye and a CBMCLC. After a month of lens wear, the binocular distance visual acuity (BDVA, binocular near visual acuity (BNVA, defocus curve, binocular distance, and near contrast sensitivity and near stereoacuity (NSA were measured under photopic conditions (85 cd/m2. Moreover, BDVA and binocular distance contrast sensitivity were examined under mesopic conditions (5 cd/m2. Results: Visual acuity at an intermediate distance and near vision was better with the CBMCLC than with the artificial pupil (p<0.05. Statistically significant differences were found in contrast sensitivity between the two types of correction for distance (under mesopic conditions and for near vision, with the CBMCLC exhibiting better results in both cases (p<0.05. The mean NSA values obtained for the artificial pupil contact lens were significantly worse than those for the CBMCLC (p=0.001. Conclusion: The CBMCLC provided greater visual performance in terms of intermediate and near vision compared with the artificial pupil contact lens.

Visual performance after the implantation of a new trifocal intraocular lens

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Vryghem JC

2013-10-01

Full Text Available Jérôme C Vryghem,1,2 Steven Heireman1,21Brussels Eye Doctors, Brussels, Belgium; 2Clinique Saint-Jean, Brussels, BelgiumPurpose: To evaluate the subjective and objective visual results after the implantation of a new trifocal diffractive intraocular lens.Methods: A new trifocal diffractive intraocular lens was designed combining two superimposed diffractive profiles: one with +1.75 diopters (D addition for intermediate vision and the other with +3.50 D addition for near vision. Fifty eyes of 25 patients that were operated on by one surgeon are included in this study. The uncorrected and best distance-corrected monocular and binocular, near, intermediate, and distance visual acuities, contrast sensitivity, and defocus curves were measured 6 months postoperatively. In addition to the standard clinical follow-up, a questionnaire evaluating individual satisfaction and quality of life was submitted to the patients.Results: The mean age of patients at the time of surgery was 70 ± 10 years. The mean uncorrected and corrected monocular distance visual acuity (VA were LogMAR 0.06 ± 0.10 and LogMAR 0.00 ± 0.08, respectively. The outcomes for the binocular uncorrected distance visual acuity were almost the same (LogMAR −0.04 ± 0.09. LogMAR −010 ± 0.15 and 0.02 ± 0.06 were measured for the binocular uncorrected intermediate and near VA, respectively. The distance-corrected visual acuity was maintained in mesopic conditions. The contrast sensitivity was similar to that obtained after implantation of a bifocal intraocular lens and did not decrease in mesopic conditions. The binocular defocus curve confirms good VA even in the intermediate distance range, with a moderate decrease of less than LogMAR 0.2 at −1.5 D, with respect to the best distance VA at 0 D defocus. Patient satisfaction was high. No discrepancy between the objective and subjective outcomes was evidenced.Conclusion: The introduction of a third focus in diffractive multifocal

Four-year Follow-up of the Changes in Anterior Segment After Phakic Collamer Lens Implantation.

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Lu, Yuanyuan; Yang, Na; Li, Xuedong; Kong, Jun

2017-06-01

To assess the changes and relationship in central vaulting, flare intensity, and crystalline lens thickness during a follow-up period of 4 years after implantable collamer lens (ICL) implantation in eyes with high myopia. Retrospective observational study. Ninety-eight eyes of 50 patients were followed up with routine measurements of central vaulting, crystalline lens thickness, endothelial cell density, and aqueous flare postoperatively. Data were analyzed by repeated-measures analysis of variance. The relationship between the annual change in crystal lens thickness after surgery and age was evaluated by Pearson correlation coefficient and linear regression. There was a continuous reduction in central vaulting and endothelial cell density as well as an increase in crystalline lens thickness in ICL eyes from 1 month onward to 5 years postoperatively (P lens thickness (r = 0.617, P lens thickness are more prominent during the first year after ICL implantation, tending to be relatively stable afterwards. The anterior inflammation during the early postoperative period synchronizes with the sharp progression of crystalline lens changes within the first year. Copyright © 2017 Elsevier Inc. All rights reserved.

Immunoglobulin Concentration in Tears of Contact Lens Wearers

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Maurya, Rajendra P.; Bhushan, Prashant; Singh, Virendra P.; Singh, Mahendra K.; Kumar, Prakash; Bhatia, Ravindra P.S.; Singh, Usha

2014-01-01

Purpose: To evaluate changes in the concentration of tear immunoglobulins in contact lens wearers. Methods: A total of 45 cases including 23 contact lens wearers (43 eyes) and 22 age and sex matched healthy controls having no ocular pathology were studied for immunoglobulins (IgA, IgG, IgM) in their tears by single radial immunodiffusion method. Results: Most of the cases used soft (56.6%) and semi-soft gas permeable (30.4%) contact lenses. Tear IgM was detected in only 17.4% and tear IgG in 43.6% of contact lens wearers, while in controls IgG was detected in 9.1% but none of the controls had IgM. There was a significant rise in total tear IgA (13.17 ± 4.44 mg/dl) in contact lens wearer as compared to controls (8.93 ± 3.79 mg/dl). Rise of tear IgA was more in symptomatic patients (15.38 ± 5.28 mg/dl) and in those wearing hard (19.73 ± 5.43 mg/dl) and semi-soft contact lenses (13.31 ± 5.43 mg/dl). A significant increase in tear IgA was noticed in subjects wearing lenses for >3 years (15.69 ± 5.39 mg/dl). About 43.4% of lens wearers were symptomatic and 80% of their lenses showed deposits and/or haziness. All cases with IgM in tear were symptomatic. Conclusion: The relation of immunoglobulin concentration with increasing duration of wear and material of contact lens shows that tear immunoglobulin rise accrues due to mechanical stimulation, hence contact lenses should not be used for a long period and lenses of hard nature should be discouraged. The maintenance, cleaning and deproteinization of the lenses are of high importance to avoid immunostimulation. PMID:25667732

Differences in daily disposable circle lens performance characteristics

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Schafer JM

2014-04-01

Full Text Available Jeffery M Schafer, William T Reindel, Marjorie J Rah, Osbert Chan, Lening Zhang Bausch & Lomb Incorporated, Rochester, NY, USA Purpose: The purpose of this evaluation was to compare the performance characteristics of two cosmetically tinted contact lenses in the circle lens category that differ in lens design, lens material, and pigment print pattern: etafilcon A (1-Day Acuvue Define; Johnson & Johnson Vision Care and hilafilcon B (Naturelle; Bausch & Lomb Incorporated. Methods: Two hundred Asian subjects (400 eyes were enrolled in this 1-month parallel, bilateral, randomized study at ten investigative sites. Study lenses were dispensed at a screening/dispensing visit, and follow-up visits occurred at 2 weeks and 1 month. Lenses were worn on a daily disposable basis. Fit characteristics were evaluated at each visit, and slit-lamp evaluations were completed at each follow-up visit. Results: Of the 200 patients enrolled, 172 (344 eyes completed the study. The proportion of eyes with fully centered lenses was statistically significantly higher for the hilafilcon B group at the 2-week and 1-month visits, P<0.05. Over all visits, 0.6% of hilafilcon B eyes demonstrated incomplete corneal coverage, whereas for the etafilcon A group, 8.5% of eyes demonstrated incomplete corneal coverage and/or edge lift. The proportion of eyes with adequate lens movement was statistically significantly higher for the hilafilcon B group, P<0.05. Over all visits, none of the hilafilcon B eyes was reported to have excessive movement, whereas for etafilcon A lenses, 10.2% of eyes were reported to have excessive movement. Conclusions: Etafilcon A lenses were significantly less likely to be fully centered and significantly more likely to have incomplete corneal coverage and/or edge lift compared with the hilafilcon B lenses. Keywords: cosmetic contact lens, circle contact lens

A Tribute to Len Barton

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Tomlinson, Sally

2010-01-01

This article constitutes a short personal tribute to Len Barton in honour of his work and our collegial relationship going back over 30 years. It covers how Len saw his intellectual project of providing critical sociological and political perspectives on special education, disability and inclusion, and his own radical political perspectives. Len's…

Pharmacokinetics of Caffeine in the Lens Capsule/Epithelium After Peroral Intake: A Pilot Randomized Controlled Study.

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Kronschläger, Martin; Stimpfl, Thomas; Ruiß, Manuel; Hirnschall, Nino; Leisser, Christoph; Findl, Oliver

2018-04-01

To determine the pharmacokinetics of perorally administered caffeine, a widely consumed and potent dietary antioxidant, in the anterior lens capsule and lens epithelial cells, a crucial cell monolayer for cataract development. Bilateral cataract patients were scheduled for cataract surgery with a caffeine abstinence of 1 week before surgery of each eye. At the day of surgery of the second eye patients were administered no drink (0-mg group) or coffee with 60-, 120-, or 180-mg caffeine. After capsulorhexis the lens capsule including lens epithelial cells was transferred to a test tube for analysis of caffeine concentration by gas chromatography-mass spectrometry (GC-MS/MS). Coffee consumption significantly (P < 0.05) increased caffeine levels of the lens capsule/epithelium in the 60-, 120-, and 180-mg group. Caffeine concentrations (caffeine ng/lens capsule/epithelium) measured as difference between 1st and 2nd eye were -0.52 ± 1.16 (0-mg group, n = 7), 1.88 ± 2.02 (60-mg group, n = 8), 2.09 ± 0.67 (120-mg group, n = 9), and 3.68 ± 1.86 (180-mg group, n = 9). The increase constant of caffeine in a linear regression model was estimated as a 95% CI 0.02 ± 0.0046 (degrees of freedom; 25; r = 0.85). Peroral intake of coffee significantly increased caffeine concentrations in the lens capsule and lens epithelial cells in a dose-dependent manner. This information is important for further investigations on preventing cataract.

Photosensitized oxidation in the ocular lens: evidence for photosensitizers endogenous to the human lens

International Nuclear Information System (INIS)

Zigler, J.S. Jr.; Goosey, J.D.

1981-01-01

Numerous investigators have attempted to associate near UV light exposure with various changes which occur to lens crystallins during aging and cataractogenesis. Recently it was shown that in vitro singlet oxygen mediated oxidation of lens crystallins produces effects very similar to those documented for crystallins from old or cataractous lenses and it was suggested that near UV photodynamic effects may play a major role in vivo in aging in the human lens. It has now been shown that certain oxidation products of tryptophan which have been identified in human lens can act as near UV photosensitizers, producing singlet oxygen. The insoluble protein fraction from human cataracts was shown to have the capacity to act as a photosensitizer. An age-related increase in photosensitizing capacity was also demonstrated in the soluble crystallins from human lens. These findings are discussed with respect to development of pigmented nuclear cataracts. (author)

A course in lens design

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Velzel, Chris

2014-01-01

A Course in Lens Design is an instruction in the design of image-forming optical systems. It teaches how a satisfactory design can be obtained in a straightforward way. Theory is limited to a minimum, and used to support the practical design work. The book introduces geometrical optics, optical instruments and aberrations. It gives a description of the process of lens design and of the strategies used in this process. Half of its content is devoted to the design of sixteen types of lenses, described in detail from beginning to end. This book is different from most other books on lens design because it stresses the importance of the initial phases of the design process: (paraxial) lay-out and (thin-lens) pre-design. The argument for this change of accent is that in these phases much information can be obtained about the properties of the lens to be designed. This information can be used in later phases of the design. This makes A Course in Lens Design a useful self-study book, and a suitable basis for an intro...

Development of Fresnel lens for improvement of rear visibility; Shikai kojo Fresnel lens no kaihatsu

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Iwamoto, K; Sanada, C; Tsukino, M [Nissan Motor Co. Ltd., Tokyo (Japan)

1997-10-01

Fresnel lenses have been widely used to increase the visual field around vehicles for drivers. However, internal reflection in these lenses has been an obstacle in producing dear images. This internal glow is generated by incident light from an unexpected direction reflecting on the non-lens surface or radiating from the non-lens surface of the Fresnel lens. The cause of internal glow has been made dear combining louver film with the lens. The newly developed technology removes obstacles in producing dear images by reducing internal glow. 7 figs.

Ultrasound assessment of diaphragmatic function in patients with amyotrophic lateral sclerosis.

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Fantini, Riccardo; Mandrioli, Jessica; Zona, Stefano; Antenora, Federico; Iattoni, Andrea; Monelli, Marco; Fini, Nicola; Tonelli, Roberto; Clini, Enrico; Marchioni, Alessandro

2016-07-01

Evaluation of diaphragm function in Amyotrophic Lateral Sclerosis (ALS) is critical in determining when to commence non-invasive mechanical ventilation (NIV). Currently, forced vital capacity (FVC) and sniff nasal inspiratory pressure (SNIP) are volitional measures for this evaluation, but require collaboration and are poorly specific. The primary aim of this study was to assess whether diaphragmatic thickness measured by ultrasound (US) correlates with lung function impairment in ALS patients. The secondary aim was then to compare US diaphragm thickness index (ΔTdi) with a new parameter (ΔTmax index). 41 patients with ALS and 30 healthy subjects were enrolled in the study. All subjects underwent spirometry, SNIP and diaphragm US evaluation, while arterial blood gases were measured in some patients only. US assessed diaphragm thickness (Tdi) at tidal volume (Vt) or total lung capacity (TLC), and their ratio (ΔTmax) were recorded. Changes (Δ) in Tdi indices during tidal volume (ΔTdiVt) and maximal inspiration (ΔTdiTLC) were also assessed. ΔTdiTLC (p <0.001) and ΔTmax (p = 0.007), but not ΔTdiVt, differed between patients and controls. Significant correlation (p < 0.05) was found between ΔTdiTLC, ΔTmax and FVC. The ROC curve analysis for comparison of individual testing showed better accuracy with Δtmax than with ΔtdiTLC for FVC (AUC 0.76 and 0.27) and SNIP (AUC 0.71 and 0.25). Diaphragm thickness assessed by ultrasound significantly correlates with global respiratory alterations in patients with ALS. ΔTmax represents a new US index of early diaphragmatic dysfunction, better related with the routinely performed lung function tests. © 2016 Asian Pacific Society of Respirology.

Pentacam Scheimpflug quantitative imaging of the crystalline lens and intraocular lens.

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Rosales, Patricia; Marcos, Susana

2009-05-01

To implement geometrical and optical distortion correction methods for anterior segment Scheimpflug images obtained with a commercially available system (Pentacam, Oculus Optikgeräte GmbH). Ray tracing algorithms were implemented to obtain corrected ocular surface geometry from the original images captured by the Pentacam's CCD camera. As details of the optical layout were not fully provided by the manufacturer, an iterative procedure (based on imaging of calibrated spheres) was developed to estimate the camera lens specifications. The correction procedure was tested on Scheimpflug images of a physical water cell model eye (with polymethylmethacrylate cornea and a commercial IOL of known dimensions) and of a normal human eye previously measured with a corrected optical and geometrical distortion Scheimpflug camera (Topcon SL-45 [Topcon Medical Systems Inc] from the Vrije University, Amsterdam, Holland). Uncorrected Scheimpflug images show flatter surfaces and thinner lenses than in reality. The application of geometrical and optical distortion correction algorithms improves the accuracy of the estimated anterior lens radii of curvature by 30% to 40% and of the estimated posterior lens by 50% to 100%. The average error in the retrieved radii was 0.37 and 0.46 mm for the anterior and posterior lens radii of curvature, respectively, and 0.048 mm for lens thickness. The Pentacam Scheimpflug system can be used to obtain quantitative information on the geometry of the crystalline lens, provided that geometrical and optical distortion correction algorithms are applied, within the accuracy of state-of-the art phakometry and biometry. The techniques could improve with exact knowledge of the technical specifications of the instrument, improved edge detection algorithms, consideration of aspheric and non-rotationally symmetrical surfaces, and introduction of a crystalline gradient index.

Luneburg lens in silicon photonics.

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