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Nihat Egemen

U ltrasonic energy can be used to fragment and emulsify tissue. With the combination of devices to perform suction and irrigation into one hand-held, self-contained unit, it is possible to excise and evacuate tumor tissue simultaneously. The primary advantages involved with the use of ultrasonic emulsification and aspiration are: 1) the lack of mechanical manipulation of normal tissue; 2) the preservation of tissue planes; and 3) the absence of thermal effects. Clinical experience with the ultrasonic aspirator has led neurosurgeons to conclude that it is a

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Jørgen Kvist Kristensen, Mogens Eiken and Fritz von Wowern

series of patients suspected of having carotid artery disease. 10 We now report and discuss the use of the method in 325 patients. Method When an ultrasonic beam is directed toward an artery, the echoes corresponding to the artery are seen to move synchronously with the arterial pulse ( Fig. 1 ). The difference in the intraarterial pressure gives the varying diameters of the artery as well as records of small changes in the position of the artery, which are represented by a horizontal displacement of the echoes. The amount of ultrasound reflected varies with

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Hiroshi Nakagawa, Sang-Don Kim, Junichi Mizuno, Yukoh Ohara and Kiyoshi Ito

W hen the ultrasonic aspirator was introduced in the late 1970s, its clinical applications quickly spread in the neurosurgical field and was used in the removal of meningioma and vestibular schwannoma. The high-speed drill has been one of the instruments of choice for removing osseous spinal lesions, but there remain many complications such as direct or heat injury to nerve, blood vessels, and normal tissue caused by the spinning drill bit. The bit may also catch hold of cotton pledgets, so-called grabbing, necessitating interruption of surgery for frequent

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Joachim Oertel, Joachim Kurt Krauss and Michael Robert Gaab

I ntracranial endoscopy is a valuable technique for various indications in neurosurgery. However, its application in intraventricular lesions is often limited to biopsy and cerebrospinal fluid pathway restoration because lesion removal is considered to be rather time consuming. 8 Ultrasonic aspiration, on the other hand, represents a well-established technique for fast and effective tissue removal in certain neurosurgical applications. 3 , 10 , 12 , 13 , 16 Therefore, the goal of the present study was to develop and investigate an ultrasonic aspirator

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Han Soo Chang, Masahiro Joko, Joon Suk Song, Kiyoshi Ito, Tatsushi Inoue and Hiroshi Nakagawa

anterior clinoidectomy, 1 , 3 , 6 , 10 , 16 which is also our preferred technique. Drilling of the optic canal, however, has its own risks. It may injure the already compromised optic nerve either directly by mechanical compression or indirectly by the heat produced by the drilling. Therefore, this procedure must be undertaken with extreme care, and it requires a certain degree of expertise. An ultrasonic bone curette ( Fig. 1 ) is a device with an oscillating metal tip developed for resection of osseous tissues. Use of this device for anterior clinoidectomy and

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Marcel Afschrift, Philippe Jeannin, Claudine de Praeter, Harko van Egmond and Dirk Voet

. Ultrasonic sector-transducer fitted with the adapter. The needle crosses the ultrasound field obliquely. The needle is introduced through the needle guide. During its penetration into the tissues, the needle is easily visualized on the screen as bright linear echoes ( Fig. 2 ). It is possible to monitor the remainder of the procedure without changing the position of the transducer. If the coronal suture is still open, the transducer can be discarded from the needle, and the position of the needle monitored from the side of the head. This last method has already been

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Martin Strowitzki, Michael Kiefer and Wolf-Ingo Steudel

, 19, 22, 24, 25 Ultrasonic control may serve as a real-time imaging tool to guide endoscopes 6 and there has been a report of ultrasonic guidance of a minicaliber endoscope via a 20-mm burr hole. 29 Furthermore, small catheter-like UPs have been introduced through the working channel of the endoscope for intraventricular orientation. 21 We present a new device that allows ultrasonic guidance and control of neuroendoscopic procedures by using rigid endoscopes as a real-time imaging modality. Materials and Methods The method originated in a recently

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Taylor J. Abel, Timothy Walch and Matthew A. Howard III

advances are now and will continue to be key procedures in the future of functional neurosurgery. What is little remembered, however, is that both procedures (i.e., extrapyramidal intervention for movement disorders and focused ultrasonic lesions of subcortical brain structures) have their origins in the pioneering work of one American neurosurgeon: Russell Meyers ( Fig. 1 ). FIG. 1. Portrait of Russell Meyers during his time as chairman of the Division of Neurosurgery at the SUI. Used with permission of the Department of Neurosurgery Archives, University of Iowa

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Jonathan M. Rubin and George J. Dohrmann

the face of the scanhead. The cross on the image was for another measurement and does not relate directly to the biopsy. Right: Scan of a biopsy of the same area as left using the modified cannula and the same parameters. The tip of the probe is clearly seen. Comment It is known that roughening or notching the surfaces of objects will improve their ultrasonic visualization. 6–8 We have produced a similar result by etching the end of a cannula with six shallow parallel rings. This procedure greatly enhances the ultrasonic images of the cannula tip

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Joachim Oertel, Michael Robert Gaab, Dirk-Thomas Pillich, Henry W. S. Schroeder, Rolf Warzok and Jürgen Piek

, waterjet dissection leads to a reduction in blood loss and parenchymal trauma compared with ultrasonic aspiration or blunt dissection. 1, 16, 21 In neurosurgery, a reduction in the amount of trauma that is produced during surgery combined with vessel preservation is of particular interest. It could contribute to a decrease in the number of operative complications, leading to a significant reduction in rates of surgical morbidity and death. Previously, several cadaver studies have shown that the waterjet method allows the accurate dissection of brain parenchyma with