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At least 289 records · Page 16Linked to original sources
PubMed2005

Arthroscopic-assisted revision of telescopic rods in osteogenesis imperfecta.

Bailey-Dubow extensible nails are intramedullary stabilization devices designed to prevent deformities and recurrent long bone fractures in patients with osteogenesis imperfecta. The rods consist of a hollow outer sleeve and a solid inner obturator, allowing for telescoping of the rods and expansion of the device with longitudinal growth of the bone. Migration of the nail into the joint is a known complication of this procedure, which can lead to pain and loss of motion. This is a case report of the use of an arthroscopic approach to manipulate femoral and tibial Bailey-Dubow rods that migrated into the knee joint.

Arthroscopy↗
PubMed2004

Intraocular telescopic lens evaluation in patients with age-related macular degeneration.

PURPOSE: To evaluate the improvement of distance and near visual acuity after removal of cataract and implantation of an 3.0x intraocular miniaturized telescope (IMT) in patients with stable atrophic type age-related macular degeneration (ARMD). SETTINGS: Instituto Oftalmológico de Alicante and a multicenter group. METHODS: In this prospective noncomparative multinational consecutive study, 40 eyes of 40 patients with dry-type ARMD were implanted with IMTs at multiple centers. Standard phacoemulsification procedure followed by enlargement of the incision to 10 mm and implantation in the capsular bag of an 3.0x IMT was carried out in all the cases. Patients were followed for 12 months. Evaluation included the differences between preoperative and postoperative uncorrected and best corrected visual acuity for far and near, position of the IMT, intraocular pressure, and occurrence of any postoperative complications. RESULTS: Mean preoperative uncorrected distance visual acuity (UCDVA) in the operated eye was 0.9 logMAR (0.125 +/- 0.01, range 0.1 to 0.3 in decimal values); at 1 year postoperatively, mean UCDVA in the operated eye was 0.6 logMAR (0.25 +/- 0.14, range 0.1 to 0.5 in decimal values). Mean preoperative uncorrected near visual acuity (UCNVA) in the operated eye was 0.8 logMAR (0.16 +/- 0.13, range 0.1 to 0.5 in decimal values); at 1 year postoperatively, mean UCNVA in the operated eye was 0.4 logMAR (0.4 +/- 0.26, range 0.1 to 1.0 in decimal values). The differences between pre- and postoperative distance and near visual acuities were statistically significant. Six cases were explanted, and 14 developed adverse effects, 7 of which were persistent. The corneal endothelium tolerated the procedure well. CONCLUSION: Implantation of IMT is feasible and plays an effective role in improving far and near visual acuity in patients with stable dry-type ARMD.

Aged↗
PubMed2006

Implantable miniature telescope for the treatment of visual acuity loss resulting from end-stage age-related macular degeneration: 1-year results.

PURPOSE: To evaluate the safety and efficacy of an implantable visual prosthetic device (IMT; VisionCare Ophthalmic Technologies, Saratoga, CA) in patients with bilateral, end-stage age-related macular degeneration (AMD). DESIGN: Prospective, open-label, multicenter clinical trial with fellow eye controls. PARTICIPANTS: A total of 217 patients (mean age, 76 years) with AMD and moderate to profound bilateral central visual acuity loss (20/80-20/800) resulting from bilateral untreatable geographic atrophy, disciform scars, or both were enrolled. METHODS: A visual prosthetic device (implantable telescope), designed to enlarge retinal images of the central visual field, was implanted monocularly in the capsular bag after lens extraction. Fellow eyes were not implanted to provide peripheral vision and served as controls. Study patients participated in 6 visual rehabilitation visits after surgery. MAIN OUTCOME MEASURES: Best-corrected distance visual acuity (BCDVA) and best-corrected near visual acuity (BCNVA), quality-of-life scores from the National Eye Institute 25-item Visual Function Questionnaire (NEI VFQ-25) and the Activities of Daily Life scale, endothelial cell density (ECD), and incidence of complications and adverse events. RESULTS: At 1 year, 67% of implanted eyes achieved a 3-line or more improvement in BCDVA versus 13% of fellow eye controls (P<0.0001). Fifty-three percent of implanted eyes achieved a 3-line or more improvement in both BCDVA and BCNVA versus 10% of fellow eyes (P<0.0001). Mean BCDVA and BCNVA improved 3.5 lines and 3.2 lines, respectively, in implanted eyes versus 0.8 lines and 1.8 lines, respectively, in fellow eyes (P<0.0001). Change in visual acuity was not related to lesion type. Mean NEI VFQ-25 scores improved by more than 7 points from baseline (P<0.01) on 7 of 8 relevant subscales. Eleven eyes did not receive the device because of an aborted procedure. Endothelial cell density was reduced by 20% at 3 months and 25% at 1 year. The decrease in ECD was correlated with postsurgical edema (P<0.0001), and there was no evidence that endothelial cell loss is accelerated by ongoing endothelial trauma after implantation. CONCLUSIONS: This implantable visual prosthesis can improve visual acuity and quality of life in patients with moderate to profound visual impairment caused by bilateral, end-stage AMD.

Activities of Daily Living↗
PubMed1999

A telescopic inverted-pendulum model of the musculo-skeletal system and its use for the analysis of the sit-to-stand motor task.

For field applicability of biomechanical methodologies aiming at assessing motor ability in disabled, or at risk of disablement (e.g. elderly), subjects, measurements must be carried out using a least perceivable to the subject and essential experimental apparatus. Since data thus obtained do not necessarily lend themselves to straightforward interpretation, they should be fed to a model of the portion of the musculo-skeletal system involved that already embodies the invariant aspects of both the modelled system and the motor task. Through such a minimum measured-input model, richer, physiology-related, and thus easier to interpret, information may be expected. In this framework, the present study investigated the sit-to-stand motor task using information obtained only from a force plate located under seat and subject's feet, a seat uniaxial load-cell and basic anthropometric parameters. Data were collected in a sample of 12 able-bodied subjects while executing the motor task at different speeds. The musculo-skeletal system was modelled as a telescopic inverted pendulum (TIP) that could vary its length (shortening or elongation) by effect of a force actuator and its orientation in space by effect of two couple actuators that were looked upon as muscle equivalent effectors. The TIP model output consisted in the kinematics and dynamics of these actuators. It allowed the identification of four functional phases in which the seat-to-stand motor task could be divided, and a detailed description of the relevant mechanics in terms of balance control and centre of mass elevation. Motor strategy modifications associated with speed variation could also be identified. For a global evaluation of the motor act it showed to be no less informative than more demanding multi-segment models. Although it is true that specific musculo-articular functions can only be inferred, the more compact information yielded by the TIP model is expected to facilitate subject and/or disability classification.

Adult↗
PubMed1997

In vivo color stability of resin-veneered telescopic dentures: a double blind pilot study.

STATEMENT OF PROBLEM: Discoloration is a major disadvantage of resin veneers on telescopic dentures. In vitro color measurements with large and flat samples of resin veneer composites have been published, but no in vivo data are available. PURPOSE: This study describes the discoloration of resin veneers in vivo by use of spectrophotometry and the L*a*b* system of the Commission Internationale de L'Eclairage (CIE). METHODS: In a clinical evaluation of this technique, two composite veneer materials were compared in 18 patients. RESULTS: Both brands discolored significantly after 1 year. While L* and a* were not changed significantly, b* and the total color difference delta E increased by approximately 2 units each year. No statistically significant differences were found between the materials.

Color↗
PubMed1996

Long-term results of vein grafts interposed in arterial defects using the telescoping anastomotic technique and fibrin glue.

Fibrin glue has been applied in the anastomosis of vein grafts placed in rat femoral arteries using the telescoping technique at both ends of the graft. 34 out of 35 grafts which were patent 1 to 3 weeks post-operatively were kept for 3 months to assess the long-term patency, and the effect of the glue on the diameters of the graft and femoral artery. All 34 grafts were patent 3 months post-operatively. Excessive enlargement of the graft diameter was alleviated by the fibrin glue without affecting the diameter of the femoral artery. The diameter at the proximal anastomosis was 66% and that at the distal anastomosis was 87% of the diameter of the femoral artery.

Anastomosis, Surgical↗
PubMed2002

[Diagnosis of ventilator-associated pneumonia: a prospective comparison of the telescoping plugged catheter with the endotracheal aspirate].

OBJECTIVE: Quantitative culture of endotracheal aspirates (EA) is widely accepted for the diagnosis of ventilator-associated pneumonia (VAP). The aim of the study was to compare the diagnostic accuracy of the EA with the blinded plugged telescoping catheter (PTC) in patients suspected of VAP. STUDY DESIGN: Prospective non-randomised observational study. PATIENTS AND METHODS: 31 patients suspected of having VAP underwent 46 bronchial samplings. An EA and a blinded PTC were performed successively in each case; the PTC result was taken as the reference standard. The EA and PTC cultures were defined positive if the result of bacterial cultures yielding were > or = 10(5) cfu.mL-1 and > or = 10(3) cfu.mL-1 respectively. RESULTS: The diagnosis of VAP could be established in 19 cases when PTC was taking as gold test. The overall agreement between the two techniques was 76%. EA had a sensitivity of 89.5%, a specificity of 66.7%, a negative predictive value of 90% and a positive predictive value of 65.4%. CONCLUSION: EA is a good diagnostic test when a non-invasive test has been chosen. The diagnosis of VAP could be excluded in 90% of cases when the EA cultures yielding were < 10(5) cfu.mL-1. His low specificity could drive in an over treatment of bronchopulmonar bacterial colonization. The accuracy of the EA compares well with that of the TPC for the diagnostic of VAP.

Adolescent↗
PubMed2001

Medium-term results of implantable miniaturized telescopes in eyes with age-related macular degeneration.

PURPOSE: To evaluate the efficacy of an implantable miniaturized telescope, the IMT, in patients with age-related macular degeneration (ARMD). SETTING: Ege University Faculty of Medicine, Ophthalmology Department, Izmir, Turkey. METHODS: Among 15 patients meeting the inclusion criteria for IMT implantation, 3 were willing to participate in this prospective clinical trial and had cataract extraction with IMT implantation. The effect of the IMT on visual outcome and daily activities was assessed over 18 months. RESULTS: All patients had some improvement in distance and near vision. However, this did not lead to significant improvements in the ability to perform daily activities. One patient had 2 attacks of mild iritis that were controlled with topical medications. In another patient, bubbles that were noted inside the IMT soon after implantation were still present at 1 year. In this patient, the IMT was replaced with a conventional poly(methyl methacrylate) intraocular lens. CONCLUSIONS: Implantation of an IMT may positively affect the visual outcome and daily activities in some ARMD patients. However, proper patient selection and fully informed patient consent and understanding are mandatory.

Aged↗
PubMed2003

Feasibility and safety of laser treatments in eyes with an intraocular implantable miniature telescope.

PURPOSE: To evaluate the feasibility and safety of laser treatments in rabbit eyes fitted with an implantable miniature telescope (IMT). SETTING: The Goldschleger Eye Research Institute, Tel-Aviv University, Sheba Medical Center, Tel-Hashomer, Israel. METHODS: In this study, IMTs were implanted in the capsular bag in 19 eyes of 19 pigmented rabbits. After the rabbits recovered from surgery, neodymium:YAG (Nd:YAG) laser iridectomy (4 eyes), Nd:YAG laser capsulotomy (8 eyes), or argon laser photocoagulation of the retina (6 eyes) was performed. One day after the laser treatment, the rabbits were killed. An observer blinded to the treatment received by individual rabbits examined the enucleated eyes histopathologically to evaluate the laser lesions and their effect on ocular tissues. RESULTS: Laser iridectomy and laser posterior capsulotomy were carried out without difficulty. Laser photocoagulation of the posterior pole and the retinal periphery could be accomplished only when the laser beam was aimed around the optic of the IMT. It was not possible to carry out effective laser treatment of the retina through the IMT's optic. Treatment was difficult when adhesions between the pupil margin and the IMT optic were encountered. CONCLUSIONS: Standard laser treatments in eyes with an IMT in the capsular bag were feasible in pigmented rabbits, whose eyes are a good model for the eyes of human patients. Laser treatment of the retina was difficult to perform when adhesions between the pupil margin and the IMT were present.

Animals↗
PubMed2000

Development of substance abuse problems among drug-involved offenders. Evidence for the telescoping effect.

PURPOSE: The present study was designed to evaluate gender differences in the development of substance abuse disorders among drug-involved offenders and to determine whether women in this population exhibit a telescoping effect (i.e., acceleration in the progression from substance use to substance abuse), which has been observed in other setting. METHOD: Participants consisted of 160 polysubstance-abusing individuals (118 men, 42 women) who were admitted to two Florida drug court programs. Data were obtained from the Addiction Severity Index, intake interviews, and archival court records. RESULTS: Female and male offenders differed significantly in the developmental trajectory of their addiction. Women offenders initiated alcohol and marijuana use significantly later in life than their male cohorts but began using cocaine earlier in the course of their addiction. Women also reported more problems related to cocaine use and significantly more prior treatment episodes. Women were found to have a shorter latency from first use of cocaine to cocaine abuse. Findings are consistent with those of previous studies examining gender differences among individuals referred for substance abuse treatment. Future directions for research and implications for treatment planning are discussed.

Analysis of Variance↗
PubMed2003

Use of surgical telescopes by senior dental students: a survey.

This survey examined the use of surgical telescopes (STs) in a large senior dental student class. The percentage of students who purchased STs, factors that influenced those purchases, frequency/patterns of use, and purchase satisfaction were investigated. The survey return rate was 85.3% (128 of 150). Among the respondents, 86% had purchased STs and 14% had not. The most frequent motive for ST purchase was advice received from others (43%); ergonomic reasons were cited by 21% of users. Fixed-lens designs were selected more frequently (70%) than flip-down systems (30%). Nearly all ST purchases were made during the first year of dental school (95%), and low-power magnification (x 2-2.5) was chosen by 88% of purchasers. STs were used more often for operative dentistry, fixed prosthodontics, endodontics, and pediatric dentistry than for practice in other disciplines. ST users expressed a high level of satisfaction with their purchases (84%). The most common reason given for not purchasing STs was being able to see well enough without them (9 of 18; 50%).

Attitude↗
PubMed1997

A telescopic stent-graft for aortoiliac implantation.

OBJECTIVES: To test a new delivery system for a telescopic stent-graft. MATERIALS: Variable overlap between the components of this stent-graft combination allows length adjustment. This device differs from other multi-component stent-grafts in that both components are contained within a single delivery system. METHODS: The stent-graft was implanted in the distal thoracic to suprarenal aorta of five pigs (35-50 kg), where the arterial diameter falls by almost 50%. The proximal and distal components of the stent-graft were targeted to bony landmarks in the vertebral column. RESULTS: Inspection of completion angiograms showed both proximal and distal stent-grafts to be within 1 mm of their target locations in all five experiments. Overall combined stent-graft length varied from 13.5 cm to 16.1 cm depending on the location of the bony landmark chosen as the distal target, and on the size of the pig. CONCLUSIONS: This system may be useful for the repair of abdominal aortic aneurysm whenever preoperative sizing is difficult due to aortic tortuosity, or precluded due to the urgency of the procedure.

Animals↗
PubMed2002

Dosimetry inside MIR station using a silicon detector telescope (DOSTEL).

The dosimetry telescope (DOSTEL) was flown on the MIR orbital station during October 1997-January 1998. The mission average contributions to the absorbed dose rates (in water) were 126 +/- 4 microGy/d and 121 +/- 13 microGy/d for the GCR and the SAA component, respectively. The mean quality factors (ICRP60) deduced from the LET-spectra are 3.5 +/- 0.2 (GCR) and 1.3 +/- 0.1 (SAA). Separate LET spectra and temporal variations of the absorbed dose rates and of the mean quality factors are presented for these two radiation components as well as for solar energetic particles of the November 6, 1997 event.

Alpha Particles↗
PubMed2005

Connecting rigidities of various precision attachments compared with the conical crown retained telescope.

The purpose of this investigation was to observe the connecting rigidity of various precision attachments and to compare their connecting rigidities with the conical crown retained telescope (CCT). The connecting rigidity of a retainer was assessed using the flexibility test to measure the mesial and distal end displacements. Four precision attachments were analyzed: the dovetail slide attachment beyeler, cylindrical slide attachment, Spang Stabilex and Mini SG. The CCT was used as the control. Although there were many statistically significant differences between the displacements with the various attachments, displacements when vertically loaded were very small: all mesial end displacements were within 3 microm and distal end displacements were 21.4 microm. The largest of the mesial end displacements when horizontally loaded was as large as 44.5 microm (dovetail slide beyeler), while the others were all below 16.5 microm. The same phenomena occurred with the distal end displacements when horizontally loaded: the largest was seen with the dovetail slide beyeler, followed sequentially by the Spang Stabilex, CCT, cylindrical slide, and the Mini SG. The distal displacement with the dovetail slide beyeler was as large as 75.2 microm; those with the others were all below 31.2 microm, with numerous statistically significant differences between the displacements with the various attachments. Thus, connecting rigidities of rigid precision attachments are very similar to CCT, and only the dovetail slide beyeler attachment is too weak to resist horizontal displacement force.

Adaptation, Physiological↗
PubMed2006

Efficient and green telescoped process to 2-methoxy-3-methyl-[1,4]benzoquinone.

A telescoped process for the preparation of 2-methoxy-3-methyl-[1,4]benzoquinone is disclosed. When this novel process is compared to the prevailing method that utilizes Na2Cr2O7 as the oxidant, the novel process represents a high yielding (95%), green, and environmentally benign alternative with H2O2 and HNO3 as the oxidants and CH3COOH as the reaction medium.

Acetic Acid↗
PubMed2003

Telescoping vascularized fibular graft: a new method.

The authors describe a case of congenital pseudarthrosis of the tibia treated with a telescoping vascularized fibular graft. The advantages of this new method are that bone union and leg-length discrepancy may be corrected simultaneously.

Bone Transplantation↗
PubMed2000

In-Flight Determination of the Plate Scale of the Extreme-Ultraviolet Imaging Telescope.

Using simultaneous observations of the Michelson Doppler Imager and Extreme-Ultraviolet Imaging Telescope (EIT) on board the Solar and Heliospheric Observatory spacecraft, we determined in flight the plate scale of the EIT. We found a value of 2&farcs;629+/-0&farcs;001 pixel-1, in fair agreement with the 2&farcs;627+/-0&farcs;001 pixel-1 value deduced from recent laboratory measurements of the focal length and much higher by 7 sigma than the 2&farcs;622 pixel-1 value of the preflight calibrations. The plate scale is found to be constant across the field of view, confirming the negligible distortion level predicted by the theoretical models of the EIT. Furthermore, the 2 sigma difference between our results and the latest laboratory measurements, although statistically small, may confirm a recent work suggesting that the solar photospheric radius may be 0.5 Mm lower than the classically adopted value of 695.99 Mm.

Journal Article↗
PubMed2000

eta Carinae: Testing a Binary Orbit Model with the Hubble Space Telescope/Space Telescope Imaging Spectrograph.

Ground-based spectroscopy of eta Car shows periodic changes in some emission-line wavelengths. These variations have been cited as strong evidence that this object is a 5.5 yr binary system and have been used to produce specific orbit models. High spatial resolution data obtained with the Hubble Space Telescope/Space Telescope Imaging Spectrograph, however, do not confirm the predicted velocity behavior; therefore, the published orbit models are almost certainly invalid. Wavelength fluctuations seen at ground-based spatial resolution most likely result from other effects, which we describe. If this object is a binary system (which has not been proven), then the parameters of the secondary star and of the orbit remain largely unknown.

Journal Article↗