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At least 199 records · Page 11Linked to original sources

Dynamics of telescoping Inovirus: a mechanism for assembly at membrane adhesions.

Telescoping of Inovirus (filamentous bacteriophage) into short hollow tubes by organic solvents suggests a molecular mechanism both for infection and for maturation of the virion at adhesions between the inner and outer bacterial membranes. The symmetry of alpha-helix subunit arrangement in the virion is related to the symmetry of leaf arrangement in plants (phyllotaxis) and is conserved in a molecular rearrangement model of the telescope.

Bacteriophages↗

Treatment of choroidal neovascularization through the implantable miniature telescope.

PURPOSE: To report a case of thermal laser photocoagulation of a choroidal neovasacular membrane through the implantable miniature telescope (IMT). DESIGN: Interventional case report. METHODS: Focal thermal laser photocoagulation was performed. Complete ablation of the neovascular lesion, visual acuity, and integrity of the IMT were assessed. RESULTS: An 81-year-old woman with a history of IMT implantation for advanced geographic atrophy related to age-related macular degeneration developed an extrafoveal choroidal neovascular lesion. The patient underwent focal laser photocoagulation through the telescope without complication. Three months after treatment, no evidence of recurrence was noted, and visual acuity remained at 20/200. The IMT was not altered by the treatment. CONCLUSIONS: Focal thermal laser photocoagulation through an IMT can successfully treat choroidal neovascularization without damaging the device.

Aged, 80 and over↗

The evaluation of benign glottic lesions: rigid telescopic stroboscopy versus suspension microlaryngoscopy.

Rigid telescopic strobo-video-laryngoscopy (RTS) is a primary clinical assessment methodology in the office evaluation of benign glottic lesions. However, diagnostic observations can be made only at the time of suspension microlaryngoscopy (SML). The records of 100 consecutive patients undergoing microlaryngoscopy for benign glottic lesions were retrospectively reviewed. Nine of 100 patients were found to have additional glottic lesions during SML. Sixteen additional lesions were noted in these nine patients. Fifteen of 16 lesions were sulci and/or mucosal bridges. Forty-five percent (4/9) of the patients with additional lesions underwent a management change intraoperatively. Three patients underwent additional surgical dissection, and one underwent less dissection than was planned. The discrepancy in diagnosis between rigid telescopic strobo-video-laryngoscopy and suspension microlaryngoscopy highlights certain key points: (1) During office endoscopy, tangential views of the medial surface of the glottis limit the diagnostic sensitivity. (2) Sulci and mucosal bridges are most subject to this limitation. (3) Informed consent should address the potential need for a change in intraoperative management. It is advisable to discuss the possibility for dissection in both vocal folds, even if a unilateral lesion is observed in the office. (4) Microlaryngoscopy is the final diagnostic step in the evaluation of glottic pathology. Meticulous inspection and palpation of the glottis are recommended during SML.

Adult↗

Removal of fish bones in the oropharynx and hypopharynx under video laryngeal telescopic guidance.

OBJECTIVE: The study goal was to present the technique and results of removal of fish bones in the oropharynx and hypopharynx under video laryngeal telescopic guidance. Study design and set From January 2001 to December 2002, a total of 27 patients with fish bones lodged in the oropharynx and hypopharynx were studied at the ENT Department of Taipei Medical University Hospital. RESULTS: All fish bones were removed smoothly without necessitating further procedures at the time of the initial clinical examination and had an uneventful clinical course. CONCLUSION: Removal of fish bones lodged at the tongue base, vallecula, and hypopharynx under video laryngeal telescopic guidance has the advantages of good illumination, clear visualization, and precise extraction.The technique has also proven to be efficient, safe, well tolerated, and with low morbidity. SIGNIFICANCE: Removal of the fish bones from difficult areas in oropharynx and hypopharynx with this technique can reduce the use of direct laryngoscope under general anesthesia.

Adult↗

Telescope anastomosis in bronchial sleeve resections with high-caliber mismatch.

BACKGROUND: The efficacy of bronchial telescope anastomosis was evaluated retrospectively in patients undergoing sleeve resections with high-caliber mismatch. METHODS: The hospital charts of patients undergoing upper and lower sleeve bilobectomy and lower lobe lobectomy with replantation of the middle lobe or upper lobe into the mainstem bronchus were retrospectively reviewed. Age, sex, side, TNM stage, preoperative forced expiratory volume in 1 second (FEV1 [%]), preoperative risk factors, postoperative course, survival (months), and causes of death were recorded. RESULTS: Fifteen patients suffering from bronchial carcinoma were operated on. In 6 cases FEV1 was less than 2 L (FEV1 49% to 80%, mean 64.3, median 61). Three patients were 70 years and older. There were 7 high-risk cases presenting with coronary heart disease (n = 3), chronic alcoholism (n = 3), cerebrovascular disease (n = 1), and active tuberculosis (n = 1). Local radicality was achieved in all patients but 1, in whom pneumonectomy was contraindicated. There was no postoperative mortality. Early complications consisted of 1 anastomotic dehiscence successfully closed with an intercostal flap and 1 patient with bilateral pneumonia requiring mechanical ventilation for 5 days. One parenchymal fistula led to prolonged drainage; in 1 patient pneumothorax after removal of the chest tube required redrainage. There were no late complications, and no anastomotic stenosis developed. Survival ranged from 12 to 56 months (median 29.8, mean 30, SD 15.7). Seven patients died between 3.9 and 14 months postoperatively (mean 8.5, median 6.9) of intrabronchial local recurrence (n = 1), distant recurrence (n = 3), intrathoracic recurrence (n = 1), and nontumor-related causes (n = 2). CONCLUSIONS: Telescope anastomosis is a safe and efficient technique of bronchial sleeve resection.

Adult↗

Boron concentrations in brain during boron neutron capture therapy: in vivo measurements from the phase I trial EORTC 11961 using a gamma-ray telescope.

PURPOSE: Gamma-ray spectroscopic scans to measure boron concentrations in the irradiated volume were performed during treatment of 5 patients suffering from brain tumors with boron neutron capture therapy (BNCT). In BNCT, the dose that is meant to be targeted primarily to the tumor is the dose coming from the reaction 10B(n,alpha)7Li, which is determined by the boron concentration in tissue and the thermal neutron fluence rate. The boron distribution throughout the head of the patient during the treatment is therefore of major interest. The detection of the boron distribution during the irradiation was until now not possible. METHODS AND MATERIALS: Five patients suffering from glioblastoma multiforme and treated with BNCT in a dose escalation study were administered the boron compound, boron sulfhydryl (BSH; Na(2)B(12)H(11)SH). Boron concentrations were reconstructed from measurements performed with the gamma-ray telescope which detects locally the specific gamma rays produced by neutron capture in 10B and 1H. RESULTS: For all patients, at a 10B concentration in blood of 30 ppm, the boron concentration in nonoperated areas of the brain was very low, between 1 and 2.5 ppm. In the target volume, which included the area where the tumor had been removed and where remaining tumor cells have to be assumed, much higher boron concentrations were measured with large variations from one patient to another. Superficial tissue contained a higher concentration of 10B than the nonoperated areas of the brain, ranging between 8 and 15 ppm. CONCLUSIONS: The measured results correspond with previous tissue uptake studies, confirming that normal brain tissue hardly absorbs the boron compound BSH. Gamma-ray telescope measurements seem to be a promising method to provide information on the biodistribution of boron during therapy. Furthermore, it also opens the possibility of in vivo dosimetry.

Boron↗

The evaluation of the removal forces on the conus crowned telescopic prostheses with the finite element analysis (FEA).

The removable partial dentures supported by the telescopic crowns are an alternative for directly retained removable partial dentures. The stress distribution on the retainers and the surrounding tissues created by the telescopic and conus crowns of different sizes (4, 5, 6 mm) and taper (0 degrees, 2 degrees, 4 degrees, 6 degrees ) was investigated with the finite element analysis (FEA) method. The stress values obtained were evaluated either as strain or tensional forces. The loosening force of the secondary crown being determined as 5 N, the increase in tension of the dentine, metal structure, alveolar bone, periodontal ligament and the pulp were determined by the increasing height and taper. The reason for the increase in tensional forces with increasing taper was the result of the constant loosening force of 5 N applied in all experimental models. The strain was more effective than the tension with the highest stress being in the cervical region of the metal structure. The aim of this study was to determine the force exerted on the teeth and surrounding tissues by the loosened secondary crown.

Crowns↗

[Super-selective cerebral angiography. III. Diagnostic use and therapeutic possibilities of the telescopic catheterization technic in the circulation area of the external carotid artery in man].

The diagnostic value and technical versatility of the previously described telescopic catheter system was demonstrated in 15 patients by super-selective angiography of the external carotid artery. It was possible in all patients to catheterise the individual branches with the F-catheter; the polyethylene-S-catheter could then be passed 3 to 5 cm, beyond the tip of the F-catheter. In almost half the patients, spasm of the injected artery was observed, particularly of the superficial temporal and external occipital arteries; this was reversed by intravenous papaverine and did not interfere with detailed diagnosis. It was usually possible to obtain filling of peripheral vessels, thereby demonstrating the territory of the middle meningeal artery, the scalp, sub-mandibular gland and the pinna. There were no complications as a result of the catheterisation. The usefulness and advantages of the telescopic catheter system for therapeutic neuro-radiological procedures, with embolisation of external branches in man, are discussed.

Adult↗

Laparoscopic telescope with alpha port and aesop to view open surgical procedures.

Laparoscopy has advanced surgery by allowing the surgeon to operate within a patient's abdominal and pelvic cavity with minimal trauma and scarring. The coupling of a video camera to the laparoscopic telescope has had the secondary effect of allowing others to view the surgical field either on color video monitors or by watching the video feed over the Internet at a remote location. These advancements have allowed better teaching and mentoring of operations. Open procedures can benefit from this technology as well but have suffered in the past from inadequate methods to depict the open surgical field. We used the Alpha Port and Aesop robot to position a sterile laparoscopic telescope near the surgical field to view open cholecystectomies performed on five pigs and to send the video feed over the Internet to remote physicians. Viewing the video on the monitor, the surgeons performed the operation in a comfortable ergonomic upright position. Both the surgeons and the remote physicians found the quality of the video to be excellent, and the remote physicians felt comfortable learning and mentoring surgical procedures using this technique.

Animals↗

Airway obstruction by vascular anomalies. Importance of telescopic bronchoscopy.

This review of 28 cases of airway obstruction by vascular anomalies in the past 6 years emphasizes the importance of these anomalies as causes of obstruction, stridor, and apnea in infants as well as the important contribution of telescopic bronchoscopy to the recognition of these lesions, especially compression of the trachea by the innominate artery. There were 20 patients with compression by the innominate artery; four were surgically corrected. Seven vascular ring anomalies were all corrected by operation as was an enlarged left atrium and malformed mitral valve in one patient. Vascular anomalies caused 26% of the obstructive airway lesions in a series of infants who had bronchoscopy for obstruction, stridor, or apnea. Failure to diagnose and treat these entities may result in progressive respiratory embarrassment and even death. Barium esophagogram and aortic arch arteriogram, the traditional modalities for diagnosing vascular rings, may fail to identify tracheal compression by enlarged cardiac chambers or the more common "anomalous" innominate artery. Telescopic bronchoscopy will identify tracheal compression by the innominate artery; furthermore, it will identify the area of compression by the vascular ring. Observation of the compressed area during corrective surgery ensures that the operative manipulations are appropriate and successful in relieving the obstruction. This observation can be facilitated by televised monitoring and videotaping.

Airway Obstruction↗

Indirect laryngeal photography using rigid telescopes.

A technique for indirect laryngeal color photography for the office or clinic using rigid rod-lens angled telescopes is outlined. The photographic equipment can be used for documentation at both direct and indirect laryngoscopy except that the latter requires purpose-designed 70 degrees or 90 degrees telescopes. The method, which requires practice and patience, and the equipment are described in detail, and the difficulties and frustrations that are encountered are discussed.

Female↗

Reading with a 10X telescope.

A 10-yr-old partially sighted, one-eyed patient with 10/200 distance acuity and no experience in using an optical aid was able to read successfully by using a 10 x Selsi telescope with a + 3.50 D reading cap, an easel to hold in material upright and free his hands to hold the telescope and write, and a high-intensity desk lamp to provide adequate retinal illiumination through a congenital cataract.

Cataract↗

Reverse Galilean telescopic spectacles in unilateral aphakia.

Minimizing aniseikonia in unilateral aphakia is often a difficult task. A case is presented in which a patient preferred a reverse Galilean telescopic spectacle of his own design to a contact lens. The design of the spectacles and the patient's visual performance with them are described. A reverse Galilean telescopic spectacle should not be excluded from the therapeutic alternatives in unilateral aphakia.

Aphakia, Postcataract↗

Magnification limitations of a contact lens telescope.

A contact lens telescope (CLTS) may have some applications as a low vision aid. In certain circumstances, it offers the possibility of a larger field of view and may simplify the optical alignment difficulties of the user who has a central scotoma. Such devices in the past have usually been limited to magnifications of 2X or less. I examined the magnification potential of these devices by using an unusually high contact lens power and measuring the actual visual acuity improvement (functional magnification) achievable by young, normally sighted subjects. The results show the functional magnification to be significantly reduced compared with the theoretical magnification calculated by the afocal telescope magnification formula. This degradation of functional magnification would be expected to be even greater when used by the visually impaired.

Accommodation, Ocular↗

An instrument for measuring the modulation transfer functions of low power telescopes and telemicroscopes.

An instrument using an electro-optical Fourier method for measuring the modulation transfer function (MTF) of low power telescopes and telemicroscopes is described. Because these devices are afocal, or nearly so, relay optics are needed to form real images at the detection section of the apparatus. The system is capable of measuring the MTF in monochromatic and white light, at any target azimuth, across the field of view, and through focus. The target system contains 14 square-wave gratings with spatial frequencies that range from 2.5 to 156 cpd. Images of these gratings are scanned across a slit. The output data are fed to a first-order recursive digital Butterworth bandpass filter for MTF analysis. The apparatus is diffraction limited at f/31.4. Therefore, it negligibly affects the measurement of the MTF of telescopes and telemicroscopes tested with exit pupils of up to 6.4 mm.

Equipment Design↗

Unexpectedly large enhancement of a severely constricted field with reversed Galilean telescopes.

A 25-year-old female presented with severely constricted visual fields secondary to stroke associated with mitral valve prolapse. Repeatably measured central fields of less than 4 degrees diameter showed an unexpected enlargement up to 20 to 40 degrees diameter, when fitted with reversed full field 1.3x and 1.7x Galilean telescopes. Although initial tests indicated no psychogenic component, fields of approximately 20 degrees diameter were eventually obtained through an imitation telescope made with 2 plano lenses. This technique may be useful in determining whether there is a psychogenic component to inexplicable field results in other patients.

Adult↗