VENTRICULOGRAPHY AND MYELOGRAPHY AND ABSORBABLE RADIOPAQUE MEDIUM

The Role and Contribution of Lumbar Myelography in the Diagnosis and Treatment of Patients With Lumbar Degenerative Disorders: Clinical and Statistical Evaluation of Post-Myelography Treatment of 63 Patients

Introduction

Myelography is a radiological examination method that has been used for the diagnosis of spinal canal pathologies for a long time. More than 90 years of experience has been improved by the development of increasingly less toxic contrast agents. Nowadays, although there are many advanced diagnostic tools, lumbar myelography is a direct imaging technique and so it is a powerful diagnostic method for patients whose treatment has not been decided. The aim of our study is to evaluate the effect of lumbar myelography as a diagnostic method and its contribution to treatment.

Materials and methods

Between January 2016 and April 2018, 63 patients who were admitted to our neurosurgery clinic due to lumbar degenerative disorders and underwent myelography were included in our study. Patients over 30 years of age with lumbar disc disease, narrow spinal canal, and spinal instability, but for whom a surgical decision could not be made, were included in this study.

Results

After lumbar myelography, 55 of 63 patients underwent a surgical procedure and 8 were directed to non-surgical treatment options. The results of the patients were evaluated by Roland-Morris Low Back Pain and Disability Questionnaire (RMQ). Results showed that the contribution of selected treatment protocols to the recovery after myelography was statistically significant.

Conclusion

Nowadays, myelography is not the first choice for the diagnosis of lumbar degenerative disorders. However, according to the results of our study, lumbar myelography is an effective diagnostic tool for specific purposes.

Reflections on a career in neurosurgery

Robert Heimburger recounts his career in neurosurgery, including some of the early years of modern neurosurgery and some of the contributions he made, particularly in the areas of early repair of myelomeningocele and spinal cord tethering, high-intensity focused ultrasound for the brain, stereotactic surgery, washing hair and scalps instead of shaving for cranial surgery, and neurosurgical consultation in Asian countries. Now aged 96, he continues to have a keen mind and thorough commitment to the profession that offered him a lifetime of inspiration and service.

Neuroradiology back to the future: spine imaging

Although radiography of the spine began shortly after Roentgen's discovery in 1895, there was little written in the medical literature about spine imaging until nearly 25 years later with the development of myelography, first by using air and then a variety of positive contrast agents. The history of spine imaging before CT and MR imaging is, in large part, a history of the development of contrast agents for intrathecal use. The advent of CT and, more important, MR imaging revolutionized spine imaging. The spinal cord and its surrounding structures could now be noninvasively visualized in great detail. In situations in which myelography is still necessary, advances in contrast agents have made the procedure less painful with fewer side effects. In this historical review, we will trace the evolution of spine imaging that has led to less invasive techniques for the evaluation of the spine and its contents and has resulted in more rapid, more specific diagnosis, therapy, and improved outcomes.

Neuroradiology back to the future: brain imaging

The beginning of neuroradiology can be traced to the early 1900s with the use of skull radiographs. Ventriculography and pneumoencephalography were introduced in 1918 and 1919, respectively, and carotid angiography, in 1927. Technical advances were made in these procedures during the next 40 years that lead to improved diagnosis of intracranial pathology. Yet, they remained invasive procedures that were often uncomfortable and associated with significant morbidity. The introduction of CT in 1971 revolutionized neuroradiology. Ventriculography and pneumoencephalography were rendered obsolete. The imaging revolution continued with the advent of MR imaging in the early 1980s. Noninvasive angiographic techniques have curtailed the use of conventional angiography, and physiologic imaging gives us a window into the function of the brain. In this historical review, we will trace the origin and evolution of the advances that have led to the quicker, less invasive diagnosis and resulted in more rapid therapy and improved outcomes.

Role of weight-bearing flexion and extension myelography in evaluating the intervertebral disc

Magnetic resonance imaging has many advantages compared with myelography and/or computed tomography in evaluating the lumbar spine for herniated nucleus pulposus. The authors have included a series of three patients whose histories and physical examinations were clinically suggestive of herniated nucleus pulposus but whose magnetic resonance imaging scans were interpreted by a radiologist as a disc bulge without nerve root compression. Because all patients had not responded to a conservative care treatment program and surgical intervention was to be considered, subsequent testing with lumbar myelography with weight-bearing flexion and extension views demonstrated more clearly the presence of herniated nucleus pulposus along with compression of the nerve root; it also revealed that a positional change in the disc occurred with flexion and extension.

Fatal ascending tonic-clonic seizure syndrome

A fatal case of ascending tonic-clonic seizure (ATCS) syndrome resulted from the inadvertent, unrecognized use of a hyperosmolar ionic contrast agent during myelography. The patient presented with lower-extremity myoclonic jerking, agitation, hyperthermia, rhabdomyolysis, and disseminated intravascular coagulation. Emergency physicians must be cognizant of this unique toxidrome to initiate early, aggressive care.

Magnetic resonance myelography (MRM) as a spinal examination technique

PURPOSE

Conventional myelography involves side effects and complications due to puncture of CSF space and injection of contrast medium. On the other hand, MR-myelography (MRM) is a new noninvasive method requiring neither puncture nor contrast medium and causing no side effects. The diagnostic value and accuracy of MRM was evaluated in comparison with conventional myelography.

MATERIALS AND METHODS

In this prospective comparative study, 41 patients (17 male, 24 female, mean age 42 years) with radicular symptoms underwent conventional lumbar myelography and were also submitted to MRM. Evaluation was performed in a blind manner by two independent examiners.

RESULTS

The specificity and sensitivity of the methods are identical. MRM shows 35 cases of thecal indentation with amputation of a nerve root sheath and 6 cases of spinal stenosis. The results of conventional myelography and MRM were surgically confirmed in 38 patients.

CONCLUSIONS

Both methods have the same diagnostic accuracy, but MRM requires neither puncture nor contrast medium nor x-rays.

Inadvertent intraoperative myelography with Hypaque: case report and discussion

BACKGROUND

Myelography is routinely performed safely using nonionic water-soluble radiographic contrast media. However, inadvertent introduction of ionic contrast media into the thecal space can result in a syndrome of spasms and convulsions, which can lead to death if not recognized and dealt with in a timely manner.

METHODS

We report a case of inadvertent use of the ionic diatrizoate meglumine, an ionic contrast agent, instead of a nonionic contrast agent during intraoperative myelography.

RESULTS

The patient developed a sterotypical syndrome of ascending myoclonic spasms, resulting in rhabdomyolysis. Treatment included elevation of the head, removal of cerebrospinal fluid, administration of anticonvulsants, diuresis and sedation, and neuromuscular blockade. The patient recovered well, and there were no long-term sequelae.

CONCLUSIONS

Intrathecal introduction of ionic contrast media and the resultant syndrome must be recognized promptly and treated with aggressive medical management to address rhabdomyolysis and seizures. Ionic contrast media should be stored and marked in such a way as to avoid inadvertent use in myelography.

Very poor prognosis in cases with extravasation of the contrast medium during angiography

BACKGROUND

The rebleeding of a ruptured intracranial aneurysm in the acute stage has been thought to indicate a very poor prognosis. In our experience, the outcome of patients with extravasation of the contrast medium is worse than that of patients with rerupture under circumstances other than angiography. We demonstrated the poorer outcome of the patients with extravasation, compared to that of the patients developing rerupture under circumstances other than angiography, and examined the factors that contributed to the poorer outcome of the patients with extravasation.

METHODS

Among the 641 cases of ruptured intracranial aneurysm, we have handled over the past 10 years, 36 (5.6%) patients have rebled before surgery was performed. Thirteen patients rebled during angiography (Group I), and the remaining 23 patients rebled in other circumstances (Group II). We compared the outcome of both groups.

RESULTS

The rebleeding occurred within 6 hours of the initial rupture in 29 (80%) patients. The outcome of Group I was significantly poorer than that of Group II (p < 0.05). In Group I, SD was achieved in only 1 patient and the remaining 12 patients died, while in Group II, 8 patients were in GR or MD, 2 were in SD, and the remaining 13 patients died.

CONCLUSION

Because rebleeding during angiography most often occurs in the acute stage and because the outcome of patients with extravasation is very poor, we recommend that the performance of angiography be delayed at least between 3 and 6 hours after the initial rupture.

Serious or fatal complications after inadvertent administration of ionic water-soluble contrast media in myelography

The consequences of the inadvertent administration, by the intrathecal route, of ionic contrast media instead of iopamidol in seven subjects are reported. The ionic compounds were diatrizoate, iodamide and ioxitalamate. The outcome was fatal in three out of seven subjects, and it depended on the type and the dose of the administered contrast agent. The serious or fatal reactions observed are a tragic confirmation of the predictive power of neurotoxicity data obtained in animal studies with various iodinated water-soluble compounds. The margin of safety, represented by the ratio of LD50 i.ce. in mice to clinical dose in humans, both normalized to bodyweight, appears to reliably reflect the risk of toxic reactions after intrathecal administration of iodinated contrast agents.

Fatal complications after myelography with meglumine diatrizoate

A case of inadvertent intrathecal injection of diatrizoate meglumine is presented. After myelography with 10 ml i.e. 6.5 g Angiografin, a 76-year-old man rapidly developed myoclonus, drowsiness and excessive metabolic acidosis. He died only a few hours later. Postmortem showed non-specific brain edema. RP-HPL-Chromatography confirmed high concentration of the contrast medium in CSF (6 mg/ml) which must have induced refractory central nervous dysregulation. The lethal effects of the misapplication of this agent on the nervous system are discussed.

CT-ventriculography to control the passage of cerebrospinal fluid. Technical note

In conventional ventriculography used to confirm free passage of cerebrospinal fluid (CSF), bony overprojections often makes it difficult to visualize the contrast medium in the cranio-spinal subarachnoid spaces. CT-ventriculography offers an alternative. Because of the high density resolution, even small amounts of contrast material can be seen in the subarachnoid spaces of the cranio-cervical region. Its usefulness is demonstrated in a series of 15 cases.

Neurotoxicity of radiological contrast agents

The most important complications of intravascular administration of contrast agents include idiosyncratic (anaphylactoid) reactions, shock, congestive heart failure, cardiac arrhythmias, acute renal failure, and neurotoxic effects. The incidence of serious neurotoxic effects is low. Entry of contrast agents into the central nervous system normally is limited but may be increased by osmotic opening of the blood-brain barrier with cerebral arteriography or arch aortography. Most neurotoxic effects are thought to represent direct effects of the contrast agent on brain or spinal cord. Adverse effects with arteriography include seizures, transient cortical blindness, brain edema, and spinal cord injury. Most cases of focal brain deficit (other than cortical blindness) are attributed to embolism secondary to the catheter. Seizures may occur with intravenous administration, especially in patients with brain tumors or other processes disrupting the blood-brain barrier. The most important adverse effects observed with myelographic agents include acute and chronic meningeal reactions with iophendylate, and seizures and transient encephalopathy with metrizamide.

Metrizamide lumbar epidurography with Seldinger Technique through the sacral notch and selective nerve root injection

Lumbar epidurography serves as an important radiographic procedure in the evaluation of patients with equivocal myelography and confusing or non-diagnostic physical findings. It is particularly valuable in patients with a wide ventral epidural space secondary to previous surgery, arachnoiditis or on a congenital basis. Several techniques and various contrast agents have been employed for the procedure. A pure Seldinger technique with a caudal approach through the sacral hiatus and injection of metrizamide gives excellent visualization of the epidural space and nerve root sleeves. The proper concentration of metrizamide is crucial for optimal results. Lateral, AP, and AP oblique radiographs, occasionally combined with lateral, complex motion tomography, clearly demonstrate the root sleeves and ventral epidural space. CT scanning, with present technology, does not provide the necessary detail for evaluating the epidural space.

Gross deformity of the spine; a lumbar myelographic risk with Conray and Dimer X

Convulsions and fracture of the neck of the femur following myelography with Conray and Dimer X are reported in two patients with a gross post-tuberculous gibbus deformity of the thoracic spine. The possible causes of the increased risk associated with myelography of the patients with gibbus are discussed.

Use of pneumoencephalography to increase stereotaxic accuracy in rhesus monkeys

A radiographic method for visualizing intracranial structures for stereotaxic surgery is described. The procedure circumvents the problems associated with the use of radiopaque dyes, and it does not require modification of standard stereotaxic equipment. Anatomical data derived from the use of the method are presented, as well as an example of its application for accurately placing cannulae in the midbrain.

Experimental evaluation of watersoluble contrast media for myelography

An experimental method for testing contrast media for myelography was developed and used to compare three watersoluble contrast media, iocarmate meglumine, iothalamate meglumine and metrizamide after suboccipital myelography in 120 rabbits. A further 71 rabbits served as controls. Iocarmate and iothalamate caused vigorous convulsions; metrizamide did not. Examination of the CSF revealed an acute pleocytosis after installation of the contrast media and after cisternal puncture with injection of hypertonic saline. Histological examination of the spinal cord, nerve roots and meninges revealed pathological changes in 1 or 32 unoperatec controls (3%). Leucocyte infiltrations were found in the meninges, nerve roots and spinal cord of about 20% of the animals after myelography, after cisternal puncture without injection or with injection of hypertonic saline. There were no significant quantitative differences between the experimental groups. Degenerative changes were seen only after myelography. No meningeal fibrosis was demonstrated. An abnormal leucocyte count in the primary CSF influenced the incidence of histological changes, indicating that only rabbits with CSF cell counts within normal limits should be used in future experiments.

Intracisternal dimer X: toxicity and prophylaxis

Although Dimer X is said to be a low toxic water soluble contrast medium, epileptic seizures sometimes occur during or after Dimer X ventriculography. The toxicity of this dye was examined in rats and possible prophylactic measures were evaluated. From the results of our experiment it was concluded that Dimer X of low concentration should be used with premedication of Valium and Decadron.

Experiments with a new contrast medium in myelography

A new dimeric contrast medium, Ph DZ 59B, was injected into the subarachnoid space in experimental animals. Excellent films were invariably obtained. Ph DZ 59B was well tolerated by dogs and cats and relatively well by monkeys.

[Diagnostic possibilities of positive contrast ventriculography (author's transl)]

A comparison has been made of the relative merits of air, Conray 60, and Dimer X ventriculography in 100 cases. The great virtue of positive contrast ventriculography is its superior ability to demonstrate abnormalities in the midline and in the posterior cranial fossa. Tomoventriculography using a multiple layer cassette permits exact localization of intraventricular lesions without causing additional discomfort to the patient. The subtraction technique confers additional benefits. Positive contrast ventriculography has its limitations when there are large extraventricular masses.

Metrizamide in radiography of the central nervous system. A preliminary report

Metrizamide seems to be a suitable contrast medium for ventriculography and myelography. This contrast medium is less toxic and far less epileptogenic and spasmogenic than the other water-soluble contrast media in current use. No serious complications were noted in the present series. Transient changes in EEG were recorded, mainly with cervical myelographies. However, it is too early to evaluate the long-term side effects.

Filling patterns in contrast ventriculography

The filling patterns of a negative contrast material (air), a positive contrast water soluble material (Conray), and a positive contrast water insoluble material (Myodil) were examined in 60 normal ventriculograms. Using a scoring system developed for this study, Conray was found effective for outlining the ipsilateral (injected) lateral ventricle, the third ventricle, the aqueduct of Sylvius, and the fourth ventricle. Air was the most effective for the noninjected lateral ventricle, while Myodil was best for A-P demonstration of the aqueduct. The clinical implications of these findings are discussed.

Cisternal myelography using Conray

Conray-280 (meglumine iothalamate) can be injected safely into the cisterna magna in the human. In this series of 46 patients no complications were encountered attributable to the irritant effects of Conray. Satisfactory radiographic visualization was obtained in 87% of cases using 5 ml. 50% solution of Conray-280 enabling clear delineation of the anterior and posterior borders of the spinal cord to be made.

Lumbosacral myelography with Dimer-X. Report of 100 cases

✓ The authors report the use of the water-soluble spinal contrast medium Dimer-X in 100 cases of suspected lumbar disc disease. It was particularly valuable in delineating small laterally-placed protrusions causing root compression, which are often difficult to demonstrate with oily contrast media. Side effects were mild and transient, and no serious complications were encountered.