China
Africa
Explore chapters and articles related to this topic
Uro-Angiographic Contrast Agents—The Holy Grail
Published in Christoph de Haën, X-Ray Contrast Agent Technology, 2019
Metrizamide formally opened the era of water-soluble, nonionic contrast agents. Almén’s objective had been to achieve major improvements in the safety of generally usable uro-angiographic contrast agents. Measured against this objective, metrizamide failed to deliver. While it did reflect the chemical and physical design principles propagated by Almén (1969a,b), its costs of production were exorbitant and its phamaceutical presentation too cumbersome for general use. Instead, it found niche application in myelography, where to a large degree it displaced older products. With this “creative destruction” metrizamide for myelography did meet the Schumpeterian criteria for a technological innovation, an improvement innovation as it is called here. This does not apply to metrizamide for angiography. Hence, considering metrizamide as a prototype for a new generation of nonionic uro-angiographic products, on a par with what uroselectan sodium or methiodal sodium has been for first-generation products, is problematic. But metrizamide certainly was an extremely important stepping stone for finding compounds that would match expectations more fully. Metrizamide strengthened the trust in the feasibility of the targeted technology improvement in a way comparable to what PYELOGNOST had done for technology genesis.
Nausea and Vomiting in the Clinical Practices of Radiology and Anesthesia
Published in John Kucharczyk, David J. Stewart, Alan D. Miller, Nausea and Vomiting: Recent Research and Clinical Advances, 2017
M. Riding, D. S. Litz, A. Gerber
The differences in nausea and vomiting noted after i.v. administration of the ionic and nonionic low osmolality contrast media, Iohexol and Hexabrix, are not seen during intraarterial injection. Metrizamide was used briefly for cerebral angiography, but it was expensive and consequently was superseded by the newer nonionic contrast media. No significant incidence of nausea and vomiting was seen with Metrizamide, even following vertebral injection. In a comparative study of Iohexol and Metrizamide for cerebral angiography, Holtas et al.49 observed no nausea and vomiting in either group of 30 patients. The incidence of nausea and vomiting with different angiographic agents is summarized in Table 5.
Diagnosis in orthopaedics
Published in Ashley W. Blom, David Warwick, Michael R. Whitehouse, Apley and Solomon’s System of Orthopaedics and Trauma, 2017
Louis Solomon, Charles Wakeley
Metrizamide has low neurotoxicity and at working concentrations it is more or less isotonic with cere-brospinal fluid. It can therefore be used throughout the length of the spinal canal; the nerve roots are also well delineated (radiculography). A bulging disc, an intrathecal tumour or narrowing of the bony canal will produce characteristic distortions of the opaque column in the myelogram.
Pathogenesis, management strategies, and outcome of non-communicating extradural spinal arachnoid cyst (NEAC): a systematic review
Published in British Journal of Neurosurgery, 2023
Mohammad Shahidul Islam Khan, Nazmin Ahmed, Kanak Kanti Barua, Bipin Chaurasia, Atul Vats, Atul Goel
MRI is the diagnostic modalities of choice because it clearly defines the type and extent of the cyst as well as relationship with surrounding neurovascular structures. The imaging characteristics of arachnoid cysts are similar to those of CSF signal intensity (Figures 3, 4). Epidural fat capping of the lesion at its superior and inferior poles suggests its extradural location.17,37,40 The presence of vertebral body scalloping and expansion of the neural foramina from osseous remodelling suggests longstanding mass effect from the lesion. However, MR imaging may not demonstrate a communication between the cyst and subarachnoid space. The diagnostic study of choice for demonstrating the communication with the subarachnoid space is CT myelography.37 After injecting metrizamide, sometimes a communication may be visible in delayed CT scanning.35 Recently, Ying et al. described a case where they detected the position of the fistula simultaneously performing a myelography and a digital subtraction cystography. If no communication detected preoperatively, it is recommended to check per operative CSF leakage by giving repeated Valsalva manoeuver after excision of the cyst.49