Clinical implications of acute cerebrospinal fluid changes following iophendylate myelography.
Clinical features and serial cerebrospinal fluid (CSF) samples of 50 patients who underwent myelography with iophendylate were studied. Forty two patients (84%) developed one or more features suggestive of meningism lasting for 2-4 days. There was significant rise in the average (mean) CSF counts from 9.81 in the premyelogram sample to 532.6 at the end of 24 hours (p less than 0.001). Both neutrophil and lymphocyte (p less than 000) count increased. At the end of one week, there was significant decrease of total cells in the CSF to 204 (p less than 0.001). Both, neutrophils and lymphocytes decreased. There was significant rise in total proteins in the 24 hours sample, but the fall at one week was not significant statistically. The sugar and chloride values did not change significantly. All CSF samples were negative for bacterial cultures. In conclusion, a significant proportion of the patients undergoing iophendylate myelography develop clinical features suggestive of meningeal irritation and change in the CSF fractions suggestive of meningitis: however these changes are transient and do not warrant institution of chemotherapy or steroids. (+info)
Prolongation of spinal anesthesia. Differential action of a lipid drug carrier on tetracaine, lidocaine, and procaine.
This study evaluates prolongation of spinal anesthesia by incorporating local anesthetics in lipid formulation. The duration and intensity of local anesthetic effect produced by different concentrations of procaine (1%, 2%, 4%), lidocaine (1%, 2%, 4%), or tetracaine (0.5%, 1%, 2%) dissolved in normal saline were compared to those produced by the same concentration of drugs in lipid (iophendylate) solution. Fifty rabbits with chronic indwelling subarachnoid catheters were divided into ten equal groups. Three days after the operation the catheters were injected with aqueous solutions of the anesthetics, and 24 h later each animal received an equivalent dose of the corresponding drug in free-base form dissolved in iophendylate. The duration and intensity of motor blockade were assessed using a modified Bromage scale. A separate group of animals received plain normal saline and, 24 h later, iophendylate alone. The Kruskal-Wallis test followed by the Tukey-type test for nonparametric multiple comparisons and the Mann-Whitney and Friedman tests were used for statistical analysis at P less than 0.05. Normal saline or iophendylate alone did not produce any motor blockade. Our data show that iophendylate preparations of local anesthetics produce prolonged but less intense motor blockade than the aqueous solutions, except for tetracaine 0.5% in iophendylate, which produced shorter duration of motor blockade. The reduced intensity of motor blockade may be explained by decreased availability of local anesthetic at the nerve tissue due to storage of drug in the lipid depot. The increased duration of blockade signifies a sustained release of drug from the depot. (+info)
Thoracic arachnoiditis, arachnoid cyst and syrinx formation secondary to myelography with Myodil, 30 years previously.
Spinal arachnoiditis can rarely occur following irritation from foreign body substances, including certain oil based contrast agents used for myelography. We describe a patient with thoracic arachnoiditis, arachnoid cyst and syringomyelia, 30 years following a myelogram with Myodil. A 62-year-old female presented with chronic thoraco-lumbar back pain, a spastic paraparesis and sphincter disturbance. She had undergone a myelogram with Myodil, 30 years previously for investigation of back pain. A MRI scan revealed evidence of arachnoiditis, thoracic syringomyelia (T6-T8) and an anteriorly placed, extramedullary, arachnoid cyst at T10-T12, compressing the cord. At surgery, T7-T10 thoracic laminectomies were carried out and syringo- and cysto-subarachnoid shunts were inserted. At 12 months follow-up, the sphincter disturbance, lower limb weakness and mobility problems had almost resolved. Although, the use of oil based contrast agents such as Myodil has been discontinued, the present case illustrates some of the rare sequelae of its use, manifesting decades later. Aggressive surgical intervention produced symptomatic benefit. (+info)
Iodine-based liquid radiographic contrast agents were placed in normal and tumor-bearing (Greene strain) rabbit eyes to evaluate their ability to block iodine-125 radiation. This experiment required the procedures of tumor implantation, vitrectomy, air-fluid exchange, and 125I plaque and thermoluminescent dosimetry (TLD) chip implantation. The authors quantified the amount of radiation attenuation provided by intraocularly placed contrast agents with in vivo dosimetry. After intraocular insertion of a blocking agent or sham blocker (saline) insertion, episcleral 125I plaques were placed across the eye from episcleral TLD dosimeters. This showed that radiation attenuation occurred after blocker insertion compared with the saline controls. Then computed tomographic imaging techniques were used to describe the relatively rapid transit time of the aqueous-based iohexol compared with the slow transit time of the oil-like iophendylate. Lastly, seven nontumor-bearing eyes were primarily examined for blocking agent-related ocular toxicity. Although it was noted that iophendylate induced intraocular inflammation and retinal degeneration, all iohexol-treated eyes were similar to the control eyes at 7 and 31 days of follow-up. Although our study suggests that intraocular radiopaque materials can be used to shield normal ocular structures during 125I plaque irradiation, a mechanism to keep these materials from exiting the eye must be devised before clinical application. (+info)
Magnetic resonance imaging findings of remnants of an intradural oil-based contrast agent: report of a case.