bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recanalization of Obstructed Cerebrospinal Fluid Ventricular Catheters Using Ultrasonic Cavitation
Authors: Ginsberg Howard J. , Drake James M. , Peterson Thomas M. , Cobbold Richard S.C. 
Published: October 2006

Abstract

OBJECTIVE:
Fifty percent of implanted cerebrospinal fluid (CSF) shunts fail within 2 years, primarily because of obstruction of the proximal catheter. Percutaneous techniques to reduce the morbidity of shunt revision are being developed. The authors describe the development of a device that uses ultrasonic cavitation to unblock ventricular catheters.

METHODS:
In collaboration with Cybersonics, Inc. (Erie, PA), we designed, built, and tested a system that produces low-frequency ultrasound (20–28 kHz). Extensional ultrasonic waves are transmitted along a tapered wire (final diameter, approximately 0.8 mm) to the tip, where cavitation is produced in a highly localized region. An in vitro model of sheep choroid plexus occluding typical ventricular catheters was developed. The device was safety tested in vivo in rat and pig brains by introducing the device into shunt catheters inserted during simulated shunt surgery. A clinical safety trial using the device to attempt to remove blocked and adherent ventricular catheters has commenced. RESULTS: In the sheep choroid plexus model, at least 90% of the occluded holes were unblocked in a few minutes, restoring normal flow. There was no adverse effect of the device within shunt catheters inserted into live animal brains. Four patients have undergone treatment with the device at open CSF shunt surgery without adverse effect, and the device seems effective at unblocking and freeing the occluded catheters.

CONCLUSION:
Ultrasonic cavitation produced at the end of a fine wire that is introduced percutaneously into a CSF shunt promises to be a useful technique for minimally invasive proximal ventricular CSF shunt catheter revision.
Treatment of Giant and Large Internal Carotid Artery Aneurysms With a High-Flow Replacement Bypass Using the Excimer Laser-Assisted Nonocclusive Anastomosis Technique
Authors: van Doormaal Tristan P.C. , Zwan Albert van der , Verweij Bon H. , Langer David J. , Tulleken Cornelis A.F. 
Published: October 2006

Abstract

OBJECTIVE:
To define the clinical value of the high-flow replacement bypass using the excimer laser-assisted nonocclusive anastomosis technique in the treatment of patients with a noncoilable, nonclippable giant or large intracranial aneurysm of the internal carotid artery (ICA).

METHODS:
We studied 34 patients with a giant intracranial aneurysm of the ICA proximal to its bifurcation who were treated with an extracranial-intercranial high-flow replacement bypass in our hospital between 1999 and 2004. We retrospectively collected data for patient characteristics, operative aspects, complications, and functional health scores using the modified Rankin scale. Long-term data were updated by questionnaire and telephone survey. Mean long-term follow-up period was 3.3 years (range, 0.6-5.6 yr).

RESULTS:
We were able to construct a patent bypass in 33 out of 34 patients (97%). In six patients (17%), we needed two bypass attempts. In one patient (3%), the bypass was technically impossible. After bypass construction, we occluded the ICA during or after surgery in 32 patients (94%), causing aneurysm thrombosis in all of these patients. A fatal complication occurred in two patients (6%) before we could occlude the ICA. A nonfatal complication occurred in seven patients (21%). In the long term, 25 patients (74%) had a favorable outcome and 27 patients (79%) were independent (modified Rankin scale, &lt;3).

CONCLUSION:
This study shows that the excimer laser-assisted nonocclusive anastomosis high-flow replacement bypass, which provides maximum brain protection because of its nonocclusive character, is a reliable and effective method to treat these otherwise untreatable patients.
Therapy of Brain Arteriovenous Malformations: Multimodality Treatment from a Balanced Standpoint
Authors: Richling Bernd , Killer Monika , Al-Schameri Abdul R. , Ritter Lutz , Agic Rada , Krenn Michael 
Published: October 2006

Abstract
THE THREE THERAPEUTIC modalities for arteriovenous malformation (AVM) treatment (surgery, embolization, and radiotherapy) developed in the past years with specific tools, each tool with its own qualities. Soon after the implementation of embolization for treatment of AVMs, this technique was used in combination with microsurgery; since the development of radiosurgery, treatment algorithms combining embolization with surgery and eventual subsequent radiosurgery, embolization with radiosurgery, or surgery with subsequent radiosurgery have been reported. These different combinations have been in use under the term multimodality treatment for many years, but the algorithms regarding the combination of tools, which tool has priority, and how the risk levels of each tool are assessed shows great variability among institutions. Centers with a surgical background see embolization as a technique to increase surgical feasibility and radiosurgery as a tool to complete subtotal AVM excision. Institutions with an endovascular background embolize AVMs with the aim of maximal occlusion rates and view surgery or radiosurgery as a technique to be used if the goal of total endovascular occlusion cannot be achieved. Radiosurgeons receive patients after incomplete embolization or surgical extirpation or a combination of both.
Stickleback sperm saved by salt in ovarian fluid
Authors: Elofsson Helena , Van Look Katrien J. W. , Sundell Kristina , Sundh Henrik , Borg Bertil 
Published: October 2006

SUMMARYSperm of the three-spined stickleback Gasterosteus aculeatusdisplay a prolonged motility in the presence of ovarian fluid. The ovarian fluid prolongs sperm motility in freshwater from approximately 1 min to several hours, a trait that possibly gives the stickleback its unusual ability to spawn in waters of all salinities. The aim of the study was to look for factor(s) within the ovarian fluid responsible for prolonging sperm motility as well as to investigate the possible biological importance of the ovarian fluid under natural conditions. To that end, we measured the ionic content(Na+, Cl-, Ca2+ and K+) of the ovarian fluid and prepared ionic artificial ovarian fluids. We also prepared a mannitol solution with the same osmolality as the ovarian fluid in order to distinguish between the ionic and osmotic effect. We found that the ionic artificial fluids were equally effective as the natural ovarian fluid in prolonging sperm motility and survival over a range of concentrations, whereas the mannitol solution was far less effective. By insertion of natural ovarian fluid or ovarian fluid from which macromolecules had been removed by ultra filtration in nests it was found that macromolecules help by retaining ions. We also found that ovarian fluid in water, at concentrations as low as 0.75 and 1.56%, prolonged sperm motility and that the concentration of ions(Na+) present in the nest 15 min after spawning corresponded to at least 3% ovarian fluid. Previous fertilisation experiments have shown that it takes at least 15 min for stickleback sperm to fertilise all eggs in a batch. This indicates that the role of ovarian fluid in prolonging the sperm motility is biologically relevant and that the effect is exerted by the fluid's ionic content.
A `bright zone' in male hoverfly (Eristalis tenax) eyes and associated faster motion detection and increased contrast sensitivity
Authors: Straw Andrew D. , Warrant Eric J. , O'Carroll David C. 
Published: October 2006

SUMMARY
Eyes of the hoverfly Eristalis tenax are sexually dimorphic such that males have a fronto-dorsal region of large facets. In contrast to other large flies in which large facets are associated with a decreased interommatidial angle to form a dorsal `acute zone' of increased spatial resolution, we show that a dorsal region of large facets in males appears to form a `bright zone' of increased light capture without substantially increased spatial resolution. Theoretically, more light allows for increased performance in tasks such as motion detection. To determine the effect of the bright zone on motion detection, local properties of wide field motion detecting neurons were investigated using localized sinusoidal gratings. The pattern of local preferred directions of one class of these cells, the HS cells, in Eristalis is similar to that reported for the blowfly Calliphora. The bright zone seems to contribute to local contrast sensitivity; high contrast sensitivity exists in portions of the receptive field served by large diameter facet lenses of males and is not observed in females. Finally, temporal frequency tuning is also significantly faster in this frontal portion of the world, particularly in males, where it overcompensates for the higher spatial-frequency tuning and shifts the predicted local velocity optimum to higher speeds. These results indicate that increased retinal illuminance due to the bright zone of males is used to enhance contrast sensitivity and speed motion detector responses. Additionally, local neural properties vary across the visual world in a way not expected if HS cells serve purely as matched filters to measure yaw-induced visual motion.
Effect of speed on stride parameters in racehorses at gallop in field conditions
Authors: Witte T. H. , Hirst C. V. , Wilson A. M. 
Published: October 2006

SUMMARYStride duration, stance duration and protraction duration are key variables when describing the gaits of terrestrial animals. Together, they determine the duty factor (the fraction of the stride for which the limb maintains contact with the ground surface), from which the peak vertical force can be estimated. When an animal changes speed, these variables change at different proportions. Limited measurements of these variables and predictions of peak limb force have been undertaken for large mammals performing high-speed over-ground exercise. This study set out to make such measurements, employing a previously validated system consisting of limb-mounted accelerometers and a Global Positioning System data logger. Measurements were made on nine elite Thoroughbred racehorses during gallop locomotion over a range of speeds from 9 to 17 m s-1. No statistically significant differences were seen in any variables between the lead and non-lead limbs for either the fore or hind pairs of limbs. Mean stance durations of 131 and 77 ms in the forelimbs and 143 and 94 ms in the hindlimbs were recorded at speeds of 9 and 17 ms-1, respectively. Equivalent values for protraction duration were 364 and 342 (fore) and 355 and 326 ms (hind). Peak limb forces (from duty factor) at 17 ms-1 were 24.7 N kg-1 body weight (range 22.6 to 26.0 N kg-1 body weight) for the forelimbs and 15.3 N kg-1 (range 13.7-16.2 N kg-1 body weight) for the hindlimbs. The duration of the aerial phase of the stride (when no limbs are in contact with the ground) was independent of speed. Overlap time (when more than one leg is on the ground) dropped with speed and approached zero at maximum speed.
Contribution of the diaphragmaticus muscle to vital capacity in fasting and post-prandial American alligators (Alligator mississippiensis)
Authors: Uriona T. J. , Farmer C. G. 
Published: October 2006

SUMMARY
The importance of the diaphragmaticus muscle to vital capacity was investigated in juvenile American alligators by transection of this muscle. In both fasting and post-prandial animals a pneumotach was used to study vital capacity that was stimulated by either a hypercapnic-anoxic gas mixture or a hypercapnic-normoxic gas mixture in two types of control groups of animals (a shamoperated group and a group receiving no treatment) and in the experimental(transected) group. Transection did not significantly reduce vital capacity or affect time of inspiration or expiration in fasted animals. For both the experimental and control groups vital capacity was greatly reduced in post-prandial animals compared to the fasting state. Furthermore, alligators with a transected diaphragmaticus muscle showed a 16-18% greater drop in vital capacity in the post-prandial state than did alligators with an intact diaphragmaticus muscle. The post-prandial decrease in vital capacity for alligators with a transected diaphragmaticus occurred concomitantly with a significant increase in time to inspire and a decrease in maximum rate of inspiration when compared to control animals. The results from this study suggest that the diaphragmaticus muscle plays an important role in enabling large volumes of oxygen to be taken into the lungs in the post-prandial state.
The role of target elevation in prey selection by tiger beetles(Carabidae:Cicindelaspp.)
Authors: Layne John E. , Chen P. W. , Gilbert Cole 
Published: October 2006

SUMMARYThe elevation of objects in the visual field has long been recognized as a potential distance cue, but it has been demonstrated to a reasonable extent in only four species: humans, frogs, fiddler crabs and backswimmers. Many tiger beetles hunt in flat, sandy areas, and their eyes show `flat-world'adaptations, such as an extended visual streak of higher acuity that corresponds to the horizon. They are therefore possible candidates for the use of elevation as a cue for distance. We tested this empirically and with simulation. In a behavioral prey selection paradigm, in which starved beetles were presented moving prey-targets having different size, speed and elevation,the beetles showed a strong preference for large targets when these were low in the visual field and a weaker preference for small targets when these were near the horizon. Striking of targets above the horizon was reduced compared to sub-horizontal targets, and lacked the size-elevation interaction. We simulated these empirical results with a model that converted elevation to distance, and used distance to estimate the absolute size of the targets. Simulated strike probability was then determined by the similarity between this absolute size and an independently confirmed preferred prey size. The results of the simulation model matched the empirical data as well as the best statistical model of the behavioral results. While some aspects of the model,and the beetles' behavior, differ from the strict geometry of the `elevation hypothesis', our results nevertheless indicate that tiger beetles use elevation to estimate distance to prey, and that it is therefore one of the determinants of prey selection.
Tracheo‐innominate artery fistula
Authors: Weissman Bruce W. 
Published: October 2006

AbstractOne of the most dramatic complications of tracheostomy is a fistula between the trachea and the innominate artery. Our study has shown that patients at highest risk are those requiring ventilatory assistance with a cuffed tracheostomy tube placed below the level of the fourth tracheal ring.Median sternotomy has been the initial surgical procedure reported for the control of the attendant massive hemorrhage. We have found that immediate control of bleeding can be rapidly and safely accomplished by making a small suprasternal incision and compressing the innominate artery between the surgeon's finger and the undersurface of the sternum. This previously unreported use of the mediastinoscopy approach is also applicable in traumatic wounds of the lower neck, trachea and great vessels.
The effect of diazepam on vestibular compensation
Authors: Bernstein Philip , Mccabe Brian F. , Ryu Jai H. 
Published: October 2006

AbstractThe effect of diazepam (Valium) on vestibular compensation was studied in the cat. Twelve hemilabyrinthectomized cats were given diazepam (0.4 mg/kg/day — physiological dose; 1.6 mg/kg/day — toxic dose) chronically during the compensation period. Thirteen additional hemilabyrinthectomized animals were used as controls. The neural activity of the medial vestibular nucleus was monitored as well as the observations made on nystagmus and postural co‐ordination. The results indicate that diazepam does not delay vestibular compensation in the cat.
Long‐term consequences of vestibular ablation by laser in a monkey
Authors: Wilpizeski Chester , Sataloff Joseph 
Published: October 2006

AbstractA squirrel monkey having argon laser lesions of the horizontal and posterior semicircular canals showed initial suppression of nystagmus soon after irradiation. Prior to his death 417 days following surgery, the duration and frequency of caloric and rotation‐induced nystagmus was within normal limits. At no time was a significant hearing loss measured following irradiation. Histological examination of the irradiated ear showed laser craters perforating the bony canals with resultant fibrous tissue constricting the endolymphatic duct to a narrow but patent lumen. The appearance of the lesions was virtually identical to that seen in other irradiated monkeys sacrificed within several weeks after surgery. No osteogenesis or repair processes other than scar tissue in the vicinity of the laser perforations was evident. Although perhaps not useful for arresting vestibular function permanently, this laser seems to have created no deleterious side effects and may yet prove promising for other otologic microsurgical procedures requiring cutting or drilling.
The tympano‐frontal shunt: A procedure for the treatment of chronic eustachian tube insufficiency.
Authors: Goode Richard L. , Glasscock Michael 
Published: October 2006

AbstractEight ears with complications due to chronic eustachian tube insufficiency had insertion of a silicone rubber tympano‐frontal shunt tube between the mastoid antrum and the ipsilateral frontal sinus. A one‐way valve designed to open at‐10 mm H2O was placed on the tympanic end of the tube to minimize tube obstruction by ear secretions.Follow‐up an average of 20 months post insertion showed six of the eight ears to have an aerated middle ear without fluid or tympanic membrane retraction or perforation.
Drugs and the otolaryngologist
Authors: Lucente Frank E. 
Published: October 2006

AbstractNumerous clinical problems arise as a result of our use of pharmaceuticals. They include untoward pharmacologic effects, socio‐economic problems (excessive cost, abuse), improper administration and various medicolegal difficulties. Two areas of direct concern to the otolaryngologist are drug interactions and drug‐induced diseases, problems which precipitate and prolong hospitalization and which introduce a new clinical entity, “diseases of medical progress.” Otolaryngologic examples of these diseases are abundant; some are considered here in a brief explication of an area of growing concern.
The proof of the pudding
Authors: Bryce Douglas P. 
Published: October 2006

AbstractThe Centennial Conference on Laryngeal Cancer held in Toronto in May, 1974, was a success by all measurable standards.The Conference identified a great number of areas requiring continuing effort and the development of new knowledge. A standard reporting form for laryngeal cancer must be adopted throughout the world. Research in the field of laryngeal malignancy and its early diagnosis are to be emphasized. The radiological definition of the primary lesion must be improved, and the education of the public and the medical profession in the field of laryngeal diseases should be stressed.Improvement in the results of our therapy for patients with laryngeal cancer requires an intelligent international co‐operative effort.
Guest of honor's address workmen's compensation hearing loss claims
Authors: Fox Meyer S. 
Published: October 2006

AbstractThis presentation deals with the evaluation of occupational hearing loss claims, the tests used over the years to determine the hearing status of the claimants, and the various methods used to convert the results of the audiometric tests in terms of percentage of hearing impairment. A significant modification of the 1961 American Medical Association formula has recently been adopted by the Board of Directors of both the American Academy of Otolaryngology and the American Council of Otolaryngology. The modified formula has been published: “Guide for the Evaluation of Hearing Handicap,” JAMA, 241, (19): May 11, 1979.The reasons for this modification and its application in the evaluation of occupational hearing loss claims are discussed. Otolaryngologists are urged to become acquainted with the modified AAO formula and to apply it in the evaluation of hearing loss claims.
Complications of heroin injections of the neck
Authors: Espiritu Marcelo B. , Medina Jesus E. 
Published: October 2006

AbstractThe purpose of this paper is to emphasize the importance of heroin injections in the neck as an etiology of superficial and deep neck infections and to familiarize the otolaryngologist with the problems in the diagnosis and management of such infections. This study represents the first series to be reported in the world literature of patients with neck infections secondary to heroin injections.Fifty‐seven patients with neck infections related to injection of heroin in the neck (main‐lining) were studied. These patients were admitted to Detroit General Hospital during the three‐year period between January 1974 and December 1976.The clinical signs and symptoms, location of the abscesses, soft tissue radiographs of the neck, arteriograms and ultrasound examinations of the neck are discussed.The diagnostic evaluation and the treatment of the heroin addict who presents with an inflammatory neck mass are outlined, emphasizing the difficulty and the importance of differentiating between cellulitis, abscess, and pseudoaneurysms of the carotid and subclavian arteries.
Anatomical studies of the posterior petrous apex with regard to hearing preservation in acoustic neuroma removal
Authors: Domb George H. , Chole Richard A. 
Published: October 2006

AbstractSome surgeons have shown that tumors of the internal auditory canal and cerebello‐pontine angle may be removed with preservation of hearing through the suboccipital approach. If hearing is to be conserved, the cochlear division of the VIIIth cranial nerve and blood supply of the labyrinth must be preserved. In addition, surgical entry into the labyrinth, upon removal of the posterior wall of the internal auditory canal, must be avoided since it is likely to result in permanent sensorineural hearing loss.Careful anatomic dissection of 20 human temporal bones has shown that exposure of the lateral‐most recess of the internal auditory canal from a suboccipital approach is impossible without injury to the endolymphatic duct, common crus, vestibule or ampulla of the posterior semicircular canal. Previous authors have suggested that exposure of the horizontal crest may be used as a safe landmark in avoiding labyrinthine injury. However, our study has shown that exposure of the horizontal crest usually leads to labyrinthine injury. In 19 out of 20 cases, the labyrinth would have been entered had the horizontal crest been used as a landmark for the lateral limit of bone removal. The application of the anatomical relationships quantified in this study may improve our ability to avoid labyrinthine injury in the suboccipital removal of acoustic neuromas.