RESUMO
A prospective clinical trial comparing adverse postmyelographic effects and myelographic quality of metrizamide and iohexol was conducted. Using a predetermined, randomized assignment, 24 horses exhibiting neurologic signs were administered either metrizamide (180 mgl/ml) or iohexol (180 mgl/ml) via cerebellomedullary puncture. Each horse was evaluated postmyelographically for adverse effects. Myelographic quality was assessed by a numerical scoring method. Adverse effects were observed more frequently with metrizamide (21) compared with iohexol (6) myelography (p < 0.05). Seizures, intensification of preexisting neurologic signs and prolonged anesthetic recovery were the most common complications after myelography. There was no difference in myelographic quality (p > 0.05). We conclude that iohexol is safer than metrizamide for equine myelography and that quality myelograms can be obtained with either contrast medium.
Assuntos
Meios de Contraste , Doenças dos Cavalos/diagnóstico por imagem , Cavalos , Iohexol , Metrizamida , Mielografia/veterinária , Período de Recuperação da Anestesia , Anestesia por Inalação/veterinária , Anestesia Intravenosa/veterinária , Animais , Meios de Contraste/administração & dosagem , Meios de Contraste/efeitos adversos , Método Duplo-Cego , Feminino , Febre/induzido quimicamente , Febre/veterinária , Doenças dos Cavalos/induzido quimicamente , Cavalos/classificação , Iohexol/administração & dosagem , Iohexol/efeitos adversos , Masculino , Metrizamida/administração & dosagem , Metrizamida/efeitos adversos , Mielografia/métodos , Estudos Prospectivos , Punções/veterinária , Intensificação de Imagem Radiográfica , Distribuição Aleatória , Segurança , Convulsões/induzido quimicamente , Convulsões/veterinária , Doenças da Medula Espinal/diagnóstico por imagem , Doenças da Medula Espinal/veterináriaRESUMO
Cerebrospinal fluid samples from 2 groups of clinically normal dogs were compared after iopamidol (n = 9) and metrizamide (n = 8) myelography. Iopamidol (200 mg of I/ml) and metrizamide (170 mg of I/ml) were administered by cerebellomedullary injection at dosage of 0.45 ml/kg of body weight. In dogs of both groups, postmyelographic CSF changes included high specific gravity, Pandy score, protein concentration, and WBC count. The high specific gravity and Pandy score were false-positive effects attributed to nonionic contrast media. Although postmyelographic protein concentration and total WBC count were greater in CSF samples from dogs given metrizamide than in those given iopamidol, differences were not statistically significant. The differential WBC counts were consistent with mild, acute leptomeningitis; these findings were supported by results of histologic examination. Iopamidol and metrizamide should be considered low-grade leptomeningeal irritants in dogs.
Assuntos
Líquido Cefalorraquidiano/efeitos dos fármacos , Cães/líquido cefalorraquidiano , Iopamidol/efeitos adversos , Metrizamida/efeitos adversos , Animais , Contagem de Células/veterinária , Líquido Cefalorraquidiano/química , Líquido Cefalorraquidiano/citologia , Proteínas do Líquido Cefalorraquidiano/análise , Feminino , Contagem de Leucócitos/veterinária , Mielografia/veterinária , Distribuição Aleatória , Gravidade EspecíficaRESUMO
In a double blind prospective study of side effects to cervical myelography 38 patients were evaluated with neurologic examination, electroencephalography (EEG), brainstem evoked response (BER), somatosensory evoked responses (SSER), and continuous reaction times prior to and at 6 h and 24 h after myelography with either metrizamide or iohexol. A difference in the incidence of side effects (for example headache, dizziness, nausea, and neck pain) to the two different contrast media indicated that the inconveniences related to myelography were not only due to the spinal puncture. A contrast medium effect on the central nervous system varying from one agent to another was present. A high frequency of EEG deteriorations among patients with adverse clinical reactions and on only discrete affection upon BER indicated the reaction to be located to the cerebral cortex. Weakened tendon reflexes and reduced strength in the upper extremities were probably caused by blockade in the motor roots as SSER were normal indicating no affection of the sensory pathways. This hypothesis is in agreement with the fact that the patients were in the prone position in the first phase of the investigation causing the highest concentration of contrast medium around the motor roots and the anterior part of the spinal cord. Difference in metabolic effect may explain differences in side effects of metrizamide and iohexol.
Assuntos
Sistema Nervoso Central/efeitos dos fármacos , Mielografia/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Eletroencefalografia/efeitos dos fármacos , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Potenciais Somatossensoriais Evocados/efeitos dos fármacos , Feminino , Humanos , Iohexol/efeitos adversos , Masculino , Metrizamida/efeitos adversos , Pessoa de Meia-Idade , Pescoço , Estudos Prospectivos , Tempo de Reação/efeitos dos fármacosRESUMO
This study reviewed the technical complication of 112 cases of lateral C1-2 puncture myelography for cervical spinal cord disorders. Spinal cord puncture and contrast injection, puncture between the occiput and C1, and blood vessel puncture were the main complications. These principally depended on the positioning of the patient's neck (hyperextension) and misdirection of the x-ray beam. For preventing major arterial puncture, the authors also reviewed 164 vertebral angiograms and determined the pathway of the vertebral arteries and the incidence of anomaly.
Assuntos
Metrizamida/efeitos adversos , Mielografia/efeitos adversos , Punções/efeitos adversos , Convulsões/induzido quimicamente , Traumatismos da Medula Espinal/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agulhas , Doenças da Medula Espinal/diagnóstico por imagem , Artéria Vertebral/lesõesRESUMO
EEG recordings were obtained before and after intrathecal metrizamide injection in 50 consecutive patients who underwent metrizamide myelography or cisternography. EEG tracings were recorded daily until the pattern returned to baseline. One patient (2%) developed seizures. The most frequent EEG abnormality was generalized slowing of various degrees. In 15 patients (30%), the EEG record was normal throughout the study. In 4 patients (8%), EEG disturbances were seen up to the fifth day after the procedure. Patients who had undergone cervical myelography and cisternography had a marginally higher frequency of EEG disturbances than patients who underwent lumbar myelography. The causes inducing these time-related disturbances are discussed, as compared to pharmacokinetics of intrathecally administered metrizamide.
Assuntos
Encefalopatias/fisiopatologia , Eletroencefalografia , Metrizamida/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Encefalopatias/induzido quimicamente , Feminino , Humanos , Injeções Espinhais , Masculino , Metrizamida/administração & dosagem , Pessoa de Meia-Idade , Mielografia/efeitos adversos , Fatores de TempoAssuntos
Hipertermia Maligna/etiologia , Metrizamida/efeitos adversos , Adulto , Diagnóstico Diferencial , Humanos , Injeções Espinhais , Isoflurano/efeitos adversos , Masculino , Mielografia , Complicações Pós-Operatórias , Convulsões/induzido quimicamente , Succinilcolina/efeitos adversos , SíndromeAssuntos
Iohexol , Iopamidol , Mielografia/veterinária , Animais , Gatos , Cães , Cavalos , Iohexol/efeitos adversos , Iopamidol/efeitos adversos , Metrizamida/efeitos adversosRESUMO
Metrizamide, a non-ionic water soluble contrast medium, is used in myelography for detecting spinal cord lesions. Because it is an injection in the subarachnoid space, the effects on the central nervous system following metrizamide myelography should be studied. Electroencephalography can offer a non-invasive and objective method for evaluating the functions of the central nervous system. From September to December 1986, 30 cases which had received cervical or lumbar metrizamide myelography were collected. After myelography, in addition to a history review and neurologic examination, electro-encephalography was carried out within 24 hours. If the EEG record revealed abnormal, a series of EEG follow-ups were conducted until recordings were normal. The incidence of clinical adverse effects following Metrizamide myelography was 53.3% and 66.6% respectively in cervical and lumbar injections. No significant difference was found between the two groups. Secondly, the abnormal rate of the EEG record was 40.0% and 60.0% following cervical and lumbar myelography. The difference was also not significant. Lastly, the relation between clinical adverse effects and an abnormal EEG records was poor in cervical metrizamide myelography but good in lumbar myelography. The conclusions suggested by this research that the clinical adverse effects and the abnormal EEG record after metrizamide myelography are transient and are reversible changes. The mechanism of complications following cervical and lumbar metrizamide are different. Although complications may occur following cervical and lumbar metrizamide myelography, it remains a practical method in detecting spinal cord lesions.
Assuntos
Eletroencefalografia , Metrizamida/efeitos adversos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , MielografiaRESUMO
Correlation between adverse reactions and intracranial contrast media after myelography was studied. Myelography was carried out for 12 cases with metrizamide and 14 with iotrolan. In all patients, cranial CT scans were performed 18 approximately 22 hours after myelography. CT attenuation value of subarachnoid cistern was higher than the gray matter in 12 cases and lower in 14 cases. Six cases suffered from adverse reactions, but only 1 case belongs to the higher group. No correlation between adverse reactions and residual amount of contrast medium on CT was recognized.
Assuntos
Meios de Contraste/efeitos adversos , Iodobenzoatos/efeitos adversos , Metrizamida/efeitos adversos , Mielografia , Ácidos Tri-Iodobenzoicos/efeitos adversos , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Meios de Contraste/farmacocinética , Feminino , Humanos , Masculino , Metrizamida/farmacocinética , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Ácidos Tri-Iodobenzoicos/farmacocinéticaRESUMO
Effects of non-ionic contrast media on the central nervous system were compared in order to clarify any differences due to the side-chain structures among iopamidol, iotrolan, iocibidol, iohexol, iopromide, iosimide and metrizamide. The study included a primary screening test based on Irwin's method, antielectric convulsive tests using mice, measurement of the blood pressure using rats and electroencephalography using rats and rabbits. The general behavior of mice in the primary screening test revealed that tolerance to iopamidol, iotrolan and iocibidol was excellent; that to iopromide and iohexol was moderate; and that to iosimide and metrizamide was poor. Iosimide and iohexol suppressed the transient increase of blood pressure upon intravenous administration in the normal rats but not in the pithed rats. Electric stimulus increased the mortality of mice pretreated with iosimide and iohexol. Abnormal EEG with epileptic seizures, slow wave and/or flattening were observed with the administration of iopromide, iosimide or metrizamide as well as ionic contrast media. From these results, it was concluded that iopromide and metrizamide were not well tolerated in general behavior and EEG; iohexol, in general behavior, electroshock and blood pressure; and iosimide, in all experiments, while iopamidol, iotrolan and iocibidol were well tolerated. Therefore, small differences in their side-chain structures among these contrast media are considered to cause different effects on the central nervous system.
Assuntos
Comportamento Animal/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Meios de Contraste/efeitos adversos , Eletroencefalografia , Animais , Eletrochoque , Iohexol/efeitos adversos , Iopamidol/efeitos adversos , Masculino , Metrizamida/efeitos adversos , Camundongos , Coelhos , Ratos , Ratos EndogâmicosRESUMO
Differences in frequency of postmyelographic adverse reactions were analyzed with respect to sex and age in a prospective study including 1026 patients injected with metrizamide and 739 injected with iohexol. Regardless of the type of contrast medium or myelography, all types of adverse reactions were 1.4-3.8 times as frequent in women as in men. Most of the differences were statistically significant. Headache was more frequent, while vomiting and dizziness were less frequent in both women and men aged 26-50 years compared with those over 50 years of age. Dizziness and increased low back pain were consistently reported spontaneously by the patients less frequently than emerged via formal interview. The large differences between the sexes suggest that further research on contrast media toxicity would be best performed with separation of the data by gender.
Assuntos
Iohexol/efeitos adversos , Metrizamida/efeitos adversos , Mielografia/efeitos adversos , Adolescente , Adulto , Fatores Etários , Estudos de Avaliação como Assunto , Feminino , Humanos , Entrevista Psicológica , Masculino , Pessoa de Meia-Idade , Mielografia/métodos , Estudos Prospectivos , Caracteres SexuaisRESUMO
This report describes a case of metrizamide encephalopathy with persistent disturbance of consciousness and extrapyramidal symptoms. These two conditions have rarely been reported among the various adverse effects of metrizamide. An 11-year-old girl had been in almost good health until she was ten years old, at which time she received a ventriculo-peritoneal shunt operation, suffering from hydrocephalus of unknown etiology. At the age of eleven, she was admitted to our hospital due to hydrocephalus recurrence. She was examined by metrizamide shunt-gram (1200 mg iodide/4 ml). On the next day, she became drowsy. The CT scan disclosed the periventricular penetration of metrizamide into the medial part of the thalamus and the caudate nucleus. Thirteen days later, disturbance of consciousness continued, and extrapyramidal symptoms, that is, rigo-spasticity and postural tremor, were observed. Oral administration of L-threo-DOPS, the direct precursor of noradrenaline, was effective against the persistent disturbance of consciousness and L-DOPA was effective against the extrapyramidal symptoms. She soon recovered almost to normal and no neurological deficit remained. We thus conclude that the CT scan findings and effects of L-threo-DOPS and L-DOPA suggest that metrizamide encephalopathy in this case were respectively due to its periventricular penetration into the medial part of the thalamus and the caudate nucleus, and the resultant deficiency of the ascending noradrenergic reticular activating system and the nigrostriatal dopaminergic system.
Assuntos
Doenças dos Gânglios da Base/induzido quimicamente , Encefalopatias/induzido quimicamente , Transtornos Cognitivos/induzido quimicamente , Transtornos da Consciência/induzido quimicamente , Droxidopa/uso terapêutico , Extravasamento de Materiais Terapêuticos e Diagnósticos , Hidrocefalia/tratamento farmacológico , Levodopa/uso terapêutico , Metrizamida/efeitos adversos , Serina/análogos & derivados , Doenças dos Gânglios da Base/tratamento farmacológico , Encéfalo/diagnóstico por imagem , Encefalopatias/tratamento farmacológico , Encefalopatias/fisiopatologia , Criança , Transtornos da Consciência/tratamento farmacológico , Eletroencefalografia , Feminino , Humanos , Hidrocefalia/fisiopatologia , Tomografia Computadorizada por Raios XRESUMO
Absence status epilepticus following metrizamide myelography was associated with computed tomographic scan evidence of a high concentration of the dye in brain gray matter. We suggest that absence status epilepticus is due to the direct effect of metrizamide on the cortex and that this clinically treatable condition may have escaped diagnosis in previous reports.
Assuntos
Encéfalo/diagnóstico por imagem , Metrizamida/efeitos adversos , Mielografia/efeitos adversos , Estado Epiléptico/induzido quimicamente , Tomografia Computadorizada por Raios X , Adulto , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Eletroencefalografia , Humanos , Masculino , Metrizamida/farmacocinética , Estado Epiléptico/diagnóstico por imagem , Estado Epiléptico/fisiopatologiaRESUMO
In an open investigation on 100 patients, changes in the electroencephalogram following ascending cervical myelography with iopamidol 250 or metrizamide were studied. In the postmyelographic EEG, there were normal findings in 36 patients after iopamidol and 26 after metrizamide. A comparison of the pathological results after iopamidol and metrizamide yielded a relation of 6:2 for mild, 2:5 for moderate, and 0:6 for severe degree of slowing, 4:6 for basal theta wave activation, and 2:5 for increased cerebral excitability. The results were statistically significant on the 5% level according to the chi-square test.
Assuntos
Eletroencefalografia , Iopamidol , Metrizamida , Mielografia/métodos , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Avaliação de Medicamentos , Feminino , Humanos , Iopamidol/efeitos adversos , Masculino , Metrizamida/efeitos adversos , Pessoa de Meia-IdadeRESUMO
A double-blind comparative study of iohexol and metrizamide for use in cervical myelography through lumbar puncture was carried out in a group of 30 patients. No difference was found in the quality of radiographic examinations of the cervical or lumbar regions nor in the postmyelographic computed tomographic examinations of the cervical spine. The overall incidence of side effects was significantly higher in the metrizamide group (93.4%) than in the iohexol group (40%) (p = 0.002). The differences in incidence of nausea (53% in the metrizamide group compared with 13% in the iohexol group) and vomiting (46.6% with metrizamide, 6.6% with iohexol) were also significant (p = 0.02). Pyramidal signs and seizures occurred only after metrizamide myelography.