Clinical trial of iohexol for lumbar myelography

Iohexol containing 180 mg I/ml was used in 80 patients for myelography by lumbar injection. By using an adequate volume, between 10 and 20 ml, satisfactory films were obtained in all cases. Minor adverse effects occurred in 12 patients (15%) and were more frequent in women than men; they were headache (5), nausea (3), vomiting (2), back or limb pain (5), and skin rash (1) and were of minor degree in 10 cases, moderate in the other two and lasted more than 24 h in only one case. There was no change in vital signs or neurological examination related to the studies. No patient suffered difficulty with concentration, personality change or seizures. Electroencephalograms performed on 21 patients before and during the 24 h after iohexol showed no seizure or focal activity or any significant change. Repeat lumbar punctures were performed on ten patients during the 24 h following myelography. One of these, a patient with symptoms due to disc prolapse, whose CSF was abnormal prior to the myelogram, showed a slightly increased cellular response. There was no significant change in any other case. Iohexol is a very satisfactory contrast medium for myelography and compares favourably with other non-ionic contrast media.     

Iohexol in paediatric myelography

Summary Iohexol was introduced by lumbar puncture in a series of 148 consecutive children aged between 5 days and 16 years referred for myelography; no patient was excluded. Initially, iohexol 180 mgI/ml was used in dosage proportional to body weight varying between 5 ml and 15 ml. During the later part of the trial concentration of iodine was increased to 240 mg/ml for cases in which the dorsal region was of particular interest (69 patients) and to 300 mg/ml for 8 cervical studies. The total dose ranged up to 4.8 g and varied between 0.03 g and 0.51 gI/kg body weight. In all patients, neurological examinations were performed before and at 24 h and observations for adverse reactions continued over a period of 48 h. The contrast medium was run up to the foramen magnum or basal cisterns in 128 patients and to the upper dorsal region in the other 20. In the first 62 patients vital studies were performed over the period of the myelogram and for 24 h following, and an additional limited neurological examination was made at 6 h, and in the first 26 cases of the series EEG's were done before and at 24 h after the myelogram. Minor variations in pulse rate and blood pressure were observed but these were not of sufficient magnitude to be of clinical significance. In 7 patients there was minor, generally slow wave abnormality on the EEG taken after the procedure, but no spike or epileptogenic activity was obserse reactions. Focal increase in neurological signs, associated with backache and probably related to the mechaniccs of lumbar puncture and myelography, occurred in 3 tumour patients; otherwise no change in neurological condition was observed in any case. Minor reactions were observed in 24 other patients (16.2%); vomiting 14 (9.5%), headache 8 (5.7%), backache 6 (4.1%), stomache ache 2 (1.5%), mild pyrexia 3 (2.0%). The incidence and severity of these reactions was considerably less than with metrizamide myelography and all resolved within 2 days of the iohexol injection. In conclusion, iohexol has significant advantages over previously used non-ionic contrast media and is suitable for paediatric myelography.     

A double-blind, prospective, randomized, multicenter group comparison study of iopromide 240 vs iohexol 240 in myelography

The aim of this study was to evaluate the safety and efficacy of iopromide 240 mgI/ml in comparison with iohexol 240 mgI/ml in myelography. A total of 421 patients in seven centers and four countries received an average of 11.9 ml of either iopromide 240 (278 patients) or iohexol 240 (143 patients) for X-ray and/or CT myelography in a randomized (2:1), prospective, double-blind study. All patients were followed up 3–4 h after the procedure, and 327 patients remained hospitalized for 24 h. In 82 patients an EEG was recorded prior to as well as 3–4 h and 24 h after myelography. Physical examinations, including measurement of vital signs, were performed in all patients at these time points. The results were subject to statistical analysis with the primary variable being the incidence of adverse events. Both contrast media (CM) were equally effective in terms of opacification. The rating for opacity was “good” or “excellent” in 88 % for both CM. Four patients (iopromide group: n = 3; iohexol group: n = 1) had transient EEG changes but did not show clinical symptomatology. The overall rate of patients experiencing any adverse event (AE) was 16.9 % for iopromide 240 and 14.0 % for iohexol 240. Equivalence testing was inconclusive; however, the results indicated equivalence. The rate for AEs considered as study-drug related was slightly lower with iopromide 240 than with iohexol 240 (7.2 vs 7.7 %, respectively). Neither unknown nor unexpected AEs known for myelographic X-ray CM nor serious adverse events were observed. Iopromide 240 and iohexol 240 are equally safe and effective and can be recommended for myelography. Received: 19 August 1998; Revision received: 26 November 1998; Accepted: 4 February 1999     

First clinical trial with iohexol in myelography

This is a report of the first clinical trial with iohexol in lumbar myelography. The investigation was carried out as an open, non-comparative study in 30 patients and was part of a multicentre trial. Iohexol doses of 10 to 15 ml (180 mg I/ml) were used and clinical and laboratory tests were performed before and during 48 h after myelography. Spinal repuncture 6 or 24 h after myelography was done in all patients. Only minor side effects of temporary duration were recorded in 8 patients. No seizures or spikes on EEG were seen. There was no significant increase in CSF parameters such as white cell counts, protein or IgG.     

Conventional and CT metrizamide myelography in Arnold-Chiari I malformation and syringomyelia

Four normal controls and 26 cases of Arnold-Chiari I malformations and/or syringomyelia were reviewed. The pathologic cases included five isolated Arnold-Chiari I malformations, nine communicating syringomyelia, five idiopathic syringomyelia, four posttraumatic syringomyelia, one syringomyelia with hemangioblastoma, and two postshunt syringomyelia. The objectives of this study were to compare the accuracy of conventional metrizamide myelography with CT metrizamide myelography and to study indirectly the hydrodynamics of CSF flow in syringomyelia by comparing the sequential enhancement patterns of the spinal cords and cord cavities in the different groups of patients. Twenty-five patients underwent conventional metrizamide myelography immediately before CT metrizamide myelography, and one patient underwent CT metrizamide myelography only. Scans were obtained 1-2 hr, 4-8 hr, and 12-24 hr after injection of metrizamide, but not all patients were scanned during all three intervals. CT metrizamide myelography was found to be more sensitive than conventional metrizamide myelography in the diagnosis of both Arnold-Chiari I malformation and syringomyelia. Performing just an immediate and a delayed scan was found to be more cost-effective than doing all three scans. Contrary to previous reports, it was found that delayed (12-24 hr) scans demonstrated more syrinx cavities than intermediate ones. In studying the sequential enhancement patterns of the spinal cords and cord cavities, some interesting trends were observed that tend to support the theories of Aboulker and of Ball and Dayan of transneural passage of CSF into cord cavities in syringomyelia.     

Reduction of the gastrointestinal side effects of metrizamide myelography with oral dexamethasone

A prospective, double-blind study was undertaken to assess the effectiveness of oral dexamethasone premedication in reducing a variety of side effects associated with metrizamide myelography. We also examined the relationship between side effects and needle size, total metrizamide dose, radiographic findings, and personality. Patients were randomly assigned to either a placebo group (44 patients) or a dexamethasone group (38 patients). All patients completed a 24-item symptom checklist before and 24 hr after lumbar myelography. In addition, all patients completed the Minnesota Multiphasic Personality Inventory prior to myelography. Analysis of variance demonstrated a statistically significant decrease in the frequency of gastrointestinal side effects (loss of appetite, nausea, vomiting) in the dexamethasone group. There were no significant differences between the two groups for the other 21 symptoms examined. We concluded that premedication with oral dexamethasone significantly reduces the gastrointestinal side effects associated with metrizamide myelography. This reduction was especially important in older patients.     

Iotrol versus metrizamide in lumbar myelography: a double-blind study

In a prospective, randomized, double-blind study, 49 patients underwent lumbar myelography using iotrol (24 patients) or metrizamide (25 patients). The diagnostic imaging adequacy of iotrol was comparable with that of metrizamide. After iotrol myelography, adverse reactions were fewer, less severe, and of shorter duration than were those following metrizamide myelography. Thirteen of 24 patients (54%) receiving iotrol reported some adverse reactions compared with 24 of 25 patients (96%) receiving metrizamide. Five moderate and one severe adverse reaction occurred in the group receiving iotrol. Fourteen moderate and eight severe adverse reactions occurred in the group receiving metrizamide. Thirty-eight patients underwent electroencephalography both before and after myelography (19 iotrol and 19 metrizamide). None of the EEGs obtained after iotrol myelography changed from baseline, while seven of the EEGs obtained after metrizamide myelography showed changes from baseline. Iotrol was judged superior to metrizamide as a contrast medium in this patient population.     

Pharmacokinetics and tolerability of iopromide 240 after lumbar myelography.

OBJECTIVE: To evaluate the pharmacokinetics and tolerability of iopromide 240 mg iodine/mL after intrathecal administration. METHODS: Eleven patients with an indication for lumbar myelography received 10 mL iopromide 240 in an open, prospective, single-center study. All patients were followed 72 hours after the procedure and remained in the hospital. Urine was sampled from before the myelography up to 72 hours after the procedure in stages (range, 0-6, 6-12, 12-24, 24-48, and 48-72 hours). Iodine plasma levels were determined before and 30 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 9 hours, 12 hours, and 24 hours after the administration of iopromide 240. Vital signs were measured at baseline, before, and 1 and 24 hours after the procedure. Physical and neurologic examinations were performed in all patients at baseline and at the end of the study period; all adverse events were recorded. The results were subject to pharmacokinetic analysis using compartment model-independent and -dependent methods. RESULTS: Ten of 11 patients had measurable iodine plasma levels. After a lag time of approximately 0.6 hours (mean value), maximum iodine concentrations of 45% of the administered dose per total plasma volume were observed after 3.8 hours. Plasma half-lives ranged from 3.0 to 60.5 hours (model-independent methods) with a mean of 14.9 hours and a standard deviation of 17.0 hours. Using curve fitting with an open one-compartment model revealed good agreement with the model-independent methods (half-life 17.3 hours). The recovery of iodine in urine in the 72-hour period was 78%+/-15% (range, 53%-94%) as a result of an undeterminable loss of urine in some patients and prolonged half-lives in two patients. Only one patient had adverse events 24 hours after myelography. CONCLUSIONS: After lumbar myelography, iopromide 240 is almost completely excreted renally within 72 hours, with a prolonged half-life as a result of the route of administration. The kinetics of iopromide 240 after intrathecal administration are characterized by a prolonged half-life. The safety of the contrast medium was confirmed.     

Clinical trial of iohexol in lumbar myelography

Iohexol containing 180 mg I/ml was used in 20 patients for lumbar myelography. By using an adequate volume up to a maximum of 15 ml, satisfactory films were obtained in all cases. Minor or moderate adverse effects occurred in 4 patients. There were no changes in vital signs or neurologic examination related to the examinations. No patient had difficulty with concentration, personality changes or seizures. Later encephalographies performed in all patients before and during 24 h after the iohexol injections, showed no seizure or abnormal activity or any significant change. Repeated lumbar puncture was performed in 9 patients 24 h after the injection of iohexol. One of these, a patient with symptoms due to disc prolapse, whose CSF was abnormal before the myelography, had a slightly increased cellular response. There was no significant change in any of the other patients. Iohexol is a very satisfactory contrast medium for myelography and compared favorably with other non-ionic contrast media.     

Iopamidol and metrizamide for myelography: prospective double-blind clinical trial

In a comparative randomized double-blind study, 73 patients underwent myelography using iopamidol (36 patients) or metrizamide (37 patients) as contrast medium. The overall diagnostic adequacy of iopamidol myelography was found to be comparable to that of metrizamide myelography. The incidence of examinations graded as superior (64%) or adequate (36%) with iopamidol was equivalent to that with metrizamide (57% superior, 43% adequate). Adverse reactions after iopamidol myelography were fewer, less severe, and generally of shorter duration than those associated with metrizamide. In the iopamidol group, adverse reactions occurred in nine (25%) patients, all of whom experienced mild or moderate headache, one with nausea, vomiting, and fatigue. In the metrizamide group, adverse reactions occurred in 17 (46%) patients, all of whom experienced mild or moderate headache, six with nausea and vomiting and four with back and leg pain. Of nine individuals who underwent myelography using 300 mg 1/ml metrizamide injected via lateral C1-C2 puncture, three experienced a toxic encephalopathy with confusion, dysphasia, headache, nausea, and vomiting, and a fourth individual suffered severe nausea, vomiting, fever, and irregular pulse. Encephalopathy was not observed in any of the 11 patients in whom myelography was performed via lateral C1-C2 puncture with a similar concentration of iopamidol. No seizures were encountered, and no clinically significant changes in laboratory studies were observed with either contrast medium.     

Lumbar myelography with iohexol in outpatients: prospective multicenter evaluation of safety

A multicenter open, noncomparative evaluation of the safety of iohexol was prospectively conducted in 81 adult outpatients undergoing screen-film lumbar myelography. Iohexol (180 milligrams of iodine per milliliter) was administered via a lumbar route at a dose of 8-17 mL. Computed tomography (CT) was performed after myelography. The safety of iohexol was assessed by monitoring adverse reactions and neurologic status and by measuring vital signs and serum laboratory values. The most frequent adverse reaction was headache (16 of 81 patients [19.7%]). Twelve patients complained of a headache on the day of the myelographic procedure, and four patients reported a headache 24 hours after the procedure. Nausea or vomiting occurred in four of 81 patients (4.9%) only on the day myelography was performed. No other neurologic abnormalities were found. Iohexol produced myelographic and CT studies of good to excellent quality in all patients. This study indicates that iohexol can be employed safely in lumbar myelography of adult outpatients.     

Detection of cerebrospinal fluid metastasis: CT myelography or MR?

PURPOSETo determine the sensitivity of contrast MR versus myelography followed by CT in the detection of cerebrospinal fluid metastases in children with primary central nervous system tumors.METHODSThirty-three patients who had primary central nervous system malignancies had spinal MR with gadolinium within 2 weeks of a myelogram followed by CT. MR technique included T1-weighted image sequences of the entire spine with and without gadolinium. CT scans were routinely performed at T-12 to L-2, L-4 to S-1, and foramen magnum to C-2. All studies were reviewed blindly; the number, character, and location of all metastases was recorded and the results of the two studies compared. Cerebrospinal fluid cytologic findings were recorded for each patient, and compared with the results of the imaging studies.RESULTSSeven of the 33 patients had metastases detected; metastases were seen on both MR and myelography followed by CT. However, MR showed 24 lesions and myelography followed by CT showed only 15. When a lesion was seen on both MR and myelography followed by CT, the MR was usually more convincing. Superficial lesions seen on MR sometimes would be missed on myelography followed by CT. Both MR and myelography followed by CT were quite sensitive in the detection of small lesions (2 to 3 mm) when present on spinal nerve roots. Whereas MR showed multiple lesions not seen on myelography followed by CT, CT failed to show any metastases not seen on MR. Imaging studies showed metastases in 3 patients who had normal cytologic findings.CONCLUSIONSMR shows significantly more cerebrospinal fluid metastases than myelography followed by CT.     

Computed tomographic myelography in the investigation of childhood scoliosis and spinal dysraphism

The combined investigations of positive contrast myelography and computed tomographic (CT) myelography were performed on 53 consecutive children. Thirty-eight (72%) of these investigations were performed as a routine pre-operative procedure to identify occult spinal dysraphism in patients with childhood scoliosis; the remainder were because of the "orthopaedic syndrome", cervical radiculopathy, back pain and patients with clinical findings to suggest spinal dysraphism. In the 20 patients (38%) with idiopathic scoliosis, there was no case of spinal dysraphism and CT myelography provided no additional information to the myelogram. In the seven patients with spinal dysraphism the plain radiographic abnormalities identified were lumbar vertebral abnormalities (five), thoracic vertebral abnormalities (one), and sacral agenesis (one). Diastematomyelia was found in four patients, a low tethered cord and lipoma in two patients and a large lipoma in one patient. In all of these cases the myelogram indicated the intraspinal abnormalities; however, CT myelography provided more precise anatomical detail. We conclude that CT myelography is not indicated in the initial preoperative assessment of idiopathic scoliosis but should be reserved for patients with congenital or complicated scoliosis where the association with dysraphism is well recognised.     

Iohexol in lumbar myelography: preliminary results from an open, noncomparative multicenter clinical study

This is a preliminary report of the first clinical trials using iohexol as a contrast agent in lumbar myelography. The study was noncomparative and involved 82 adult patients in four centers. Iohexol doses of 10-15 ml (180 mg I/ml) were administered and clinical and laboratory tests were performed before and at intervals during 48 hr after myelography. Side effects were noted in 29 (35%) of 82 patients. Spinal repuncture 6 or 24 hr after myelography was performed in 51 patients. No significant increases in cerebrospinal fluid parameters were seen. No seizures or spikes on electroencephalography were seen.     

Detection of cerebrospinal fluid leakage: initial experience with three-dimensional fast spin-echo magnetic resonance myelography

Background: The pathogenesis of cerebrospinal fluid (CSF) hypovolemia is supposed to be caused by CSF leakage through small dural defects.

Purpose: To compare source three-dimensional (3D) fast spin-echo (FSE) images of magnetic resonance (MR) myelography with radionuclide cisternography findings, and to evaluate the feasibility of MR myelography in the detection of CSF leakage.

Material and Methods: A total of 67 patients who were clinically suspected of CSF hypovolemia underwent indium-111 radionuclide cisternography, and 27 of those who had direct findings of CSF leakage were selected for evaluation. MR myelography with 3D FSE sequences (TR/TE 6000/203 ms) was performed at the lumbar spine for all patients. We evaluated source images and maximum intensity projection (MIP) images of MR myelography, and the findings were correlated with radionuclide cisternography findings. MR myelography of five healthy volunteers was used as a reference. The MR visibility of the CSF leakage was graded as definite (leakage clearly visible), possible (leakage poorly seen), or absent (not shown).

Results: CSF leakage was identified with source 3D FSE images in 22 (81.5%) of 27 patients. Of the 22 patients, 16 were graded as definite and six were graded as possible. For the definite cases, 3D FSE images clearly showed the extent of the leaked CSF in the paraspinal structures. In the remaining five patients with absent findings, radionuclide cisternography showed only slight radionuclide activity out of the arachnoid space.

Conclusion: Source 3D FSE images of MR myelography seem useful in the detection of CSF leakage. Invasive radionuclide cisternography may be reserved for equivocal cases only.     

Ambulatory myelography using iohexol (Omnipaque): methods and results

Outpatient myelography with iohexol (Omnipaque) was performed in 150 patients. Side effects were noted in 28 patients (19%), with only 3 (2%) major complaints. It concerned 2 patients with severe and prolonged headache and one patient with seizures. Side effects were not more frequent in outpatient myelography than in reported series of hospitalized patients. The frequency of side effects was significantly lower with the use of iohexol than in comparable studies with metrizamide. Headache was the most frequent side effect, followed by an increase or exacerbation of ischiatiform pain, nausea and vomiting. Side effects were slightly more frequent in cervical myelography than in lumbar myelography and were not related to underlying pathology. It is concluded that outpatient myelography is feasable for as far as iohexol is used and patient surveillance is carefully organized.     

Thoracic disk herniation: MR imaging

The authors undertook a retrospective study to assess the role of magnetic resonance (MR) imaging in thoracic disk herniation. The initial MR images were interpreted independently of other findings. These interpretations were compared with the findings of plain and computed tomography (CT) myelography and surgery, when available. Sixteen thoracic disk herniations were confirmed with plain and CT myelography and/or surgery. Plain myelography was performed on 14 patients and showed focal ventral filling defects in nine. Results of CT myelography were equivalent to those of MR imaging with three pulse sequences (sagittal T1 and T2 weighted, axial T1 weighted) in the identification of all the abnormal levels. In two patients, the signal from the herniated disk was so low on all sequences that thoracic disk herniation had to be inferred from the mass effect on the spinal cord. Precise location of the abnormal level with body coil MR images was achieved in six of 13 patients.     

MR Myelography for Identification of Spinal CSF Leak in Spontaneous Intracranial Hypotension

BACKGROUND AND PURPOSE:CT myelography has historically been the test of choice for localization of CSF fistula in patients with spontaneous intracranial hypotension. This study evaluates the additional benefits of intrathecal gadolinium MR myelography in the detection of CSF leak.MATERIALS AND METHODS:We performed a retrospective review of patients with spontaneous intracranial hypotension who underwent CT myelography followed by intrathecal gadolinium MR myelography. All patients received intrathecal iodine and off-label gadolinium-based contrast followed by immediate CT myelography and subsequent intrathecal gadolinium MR myelography with multiplanar T1 fat-suppressed sequences. CT myelography and intrathecal gadolinium MR myelography images were reviewed by an experienced neuroradiologist to determine the presence of CSF leak. Patient records were reviewed for demographic data and adverse events following the procedure.RESULTS:Twenty-four patients met both imaging and clinical criteria for spontaneous intracranial hypotension and underwent CT myelography followed by intrathecal gadolinium MR myelography. In 3/24 patients (13%), a CSF leak was demonstrated on both CT myelography and intrathecal gadolinium MR myelography, and in 9/24 patients (38%), a CSF leak was seen on intrathecal gadolinium MR myelography (P = .011). Four of 6 leaks identified independently by intrathecal gadolinium MR myelography related to meningeal diverticula. CT myelography did not identify any leaks independently. There were no reported adverse events.CONCLUSIONS:Present data demonstrate a higher rate of leak detection with intrathecal gadolinium MR myelography when investigating CSF leaks in our cohort of patients with spontaneous intracranial hypotension. Although intrathecal gadolinium is an FDA off-label use, all patients tolerated the medication without evidence of complications. Our data suggest that intrathecal gadolinium MR myelography is a well-tolerated examination with significant benefit in the evaluation of CSF leak, particularly for patients with leak related to meningeal diverticula.

Spontaneous intracranial hypotension (SIH) is a debilitating condition with protean symptoms, which is often misdiagnosed at initial presentation.^1,2 The most common cause of SIH is a spinal CSF leak. Patients often have an underlying connective tissue disorders, though underproduction or increased absorption of CSF, dural elasticity, and minor trauma, including disk herniation, may all be contributing factors.^3,4 A reduction in CSF volume leads to compensatory dilation of venous structures in the brain, which may result in headache and subdural collections via meningeal traction.^5,6 Severe untreated cases of SIH can lead to coma and stroke.⁷CT myelography (CTM) has historically been considered the study of choice for the detection and localization of CSF leak, though a criterion standard test is difficult to establish, given the varied etiologies for SIH.⁸ Recent literature has questioned whether CTM is the most sensitive technique for the detection and localization of CSF leaks.^9,10 More recent techniques have been described, including dynamic CTM, digital subtraction myelography, heavily T2-weighted spinal MR imaging, and intrathecal gadolinium MR myelography (MRM). Both dynamic CT and digital subtraction myelography have been advocated in cases with significant spinal extra-arachnoid fluid collections on preprocedural spinal MR imaging.¹¹ MRM with intrathecal gadolinium has been shown to have a high rate of leak detection and appears safe in small doses used for myelography.¹²The mainstay of treatment for SIH is autologous epidural blood patch, initially effective in about one-third of patients.¹³ Directed epidural blood patch at the site of CSF fistula with CT guidance has been shown to be effective.¹⁴ Targeted therapy may improve clinical outcomes with evidence of benefit when the blood patch is performed as close as possible to the site of CSF fistula.¹³ Therefore, diagnostic techniques that precisely localize a CSF leak are important for guiding therapy, particularly for treatments such as fibrin glue injection and surgical repair.²Our study evaluates the relative benefit of intrathecal gadolinium MRM compared with CTM in detecting and localizing CSF leaks in patients with previously confounding diagnostic work-up to guide treatment in patients with SIH.     

Three-dimensional MR myelography of traumatic injuries of the brachial plexus.

PURPOSETo determine the diagnostic accuracy of three-dimensional MR myelography in the evaluation of traumatic injuries of the brachial plexus.METHODSTwenty patients with clinical and electromyographic evidence of traumatic brachial plexopathy were examined with three-dimensional MR myelography, conventional cervical myelography, and CT myelography 1 to 9 months after trauma. Three-dimensional MR myelography was performed on a 1.5-T MR unit with a constructive interference in steady state (CISS) technique. For each patient, maximum intensity myelographic projections and multiplanar reconstruction reformatted 1-mm axial sections were obtained from the same 3-D data set. Three-dimensional MR myelographic findings were compared with findings at cervical myelography and CT myelography. Surgical findings were available for comparison in 13 patients.RESULTSThree-dimensional MR myelography enabled detection of meningoceles with avulsed or intact nerve roots, partial or complete radicular avulsions without disruption of the thecal sac, dural sleeve abnormalities, and dural scars. Assuming cervical myelography and CT myelography as the standards of reference, 3-D MR myelography showed 89% sensitivity, 95% specificity, and 92% diagnostic accuracy in the evaluation of nerve root integrity.CONCLUSIONThree-dimensional MR myelography can show the majority of traumatic lesions that involve the proximal portion of the brachial plexus in a single rapid examination. On the basis of our findings, we propose this technique as a screening examination for patients with traumatic brachial plexus palsy.     

Comparison of MR and CT myelography in imaging the cervical and thoracic spine

MR imaging and CT myelography were compared in a retrospective study of 38 patients with suspected lesions of the cervical and thoracic spinal canal and cord. Twenty-eight abnormal cases were found, including spondylosis (9), tumors (8), intramedullary cavities (3), arachnoiditis (3), disk-space-centered infection or osteomyelitis (2), nonneoplastic cord swelling (2), and CSF-borne metastasis (1). MR was equal or superior to CT myelography in depicting cases of cord enlargement, cord compression, and cord atrophy, providing better tissue characterization, no shoulder artifact, and no limitation caused by CSF block. CT myelography was superior to MR in depicting cases of spondylosis and arachnoiditis. It showed superior spatial resolution, which was most pronounced when comparing axial images and hence particularly superior in detecting the lateral extent of disk herniation. Use of surface coils and thin imaging sections is essential for accurate and complete MR evaluation of the cervical and thoracic spine.