Diagnosis Of Spinal Cord Diseases Research Articles

Multi-Channel SQUID Magnetospinogram System With Closed-Cycle Helium Recondensing

We developed a magnetospinogram (MSG) system equipped with a closed-cycle helium recondensing unit. The MSG system detects weak magnetic fields evoked by neural activity of spinal cords using superconducting quantum interference devices (SQUIDs) and provides functional images effective for the diagnosis of spinal cord diseases. Thus far, the cost of liquid helium (LHe) required to maintain the superconductivity of the SQUID magnetometers has prevented the MSG from being used widely. Here, we combine an LHe recycling system using a pulse tube cryocooler and a low-loss transfer tube for transporting LHe to the system. This allows the superconducting state of SQUIDs to be maintained for half a year without refilling the LHe. The frequency band of noise from the recondensing system was different from that of the MSG signals. Therefore, the MSG signals were obtained at a sufficient signal-to-noise ratio even when the recondensing system, which is located just beside the magnetically shielded room, was in operation. In this paper, the details of the developed MSG system and the results from preliminary measurements using the system are reported.

Morphometric Analysis of Human Second Cervical Vertebrae (Axis)

Possessing an odontoid process and unique superior articular facets, the axis vertebra morphometry significantly differs from morphometry of other cervical vertebrae. The fractures of axis, especially its dens, are very common and surgeries highly risky. Knowledge of the axis dimensions is essential not only for preclinical studies, diagnosis of spinal cord diseases, planning of the surgeries but also for correct selection and insertion of surgical instruments or vertebral implants design. Many quantitative studies of the second cervical vertebra have been performed, yet still lacking the area parameters determination and precision of three-dimension in vivo measurement. Vertebral dimensions are reported to vary among populations, although there are very little studies examining Caucasian specimen. This study aims to provide three-dimensional in vivo morphometric analysis of the axis vertebra as well as comparison to the previous studies. The clinically relevant vertebral dimensions were measured on the threedimensional model reconstruction of CT scans providing high accuracy. Five human second cervical vertebrae were investigated (Caucasian males) and linear, area and angular dimensions were measured. The data on vertebral body dimensions were best fitting Doherty and Naderi measurement. The vertebra body anterior height was established to be 26.2 mm and the posterior height 21.4 mm. The dens parameters were similar to those presented by Doherty. Doherty also reported large variation in the dens sagittal angle which was observed in the present study as well. The dens height was determined to be 17.8 mm which is significantly greater compared to the previous studies. The smallest height among specimens was reported to be 17.0 mm. The smallest anteroposterior or transverse diameter of the dens measured was the upper depth, 9.4 mm. The smallest and biggest areas of dens were measured to be 79.0 mm2 and 121.6 mm2. The superior articular facet area with mean value 211.2 mm2 was observed to be significantly bigger than the inferior area, 141.2 mm2. The mean sagittal angle of the inferior facet area was assessed to be 42.1° and the mean frontal angle of the superior articular facet 69.3°. The parameters of articular facets measured by Xu correspond to the present study. Due to the vertebral body enlargement in the inferior part of vertebra, the spinal canal superior depth,18.0 mm, was observed to be bigger than its inferior depth, 16.2 mm. In case of the spinal canal depth, Sengul measured values considerably greater than other studies. However, Singla, Gosavi and Xu presented the parameters very similar to the present study. Spinal canal width was measured to be 24.4 mm supporting the measurement done by Sengul which is 24.7 mm. The measured vertebral dimensions can be used either for development of instrumentation, preclinical planning of surgeries, implant design or as the reference values for evaluation and diagnosis of various clinical conditions.

Myelopathy: chameleons and mimics

The diagnosis of spinal cord disease may be delayed or missed if the presentation does not conform to the expected pattern of a symmetrical spastic paraparesis with sphincter dysfunction and...

Cardiovascular and respiratory alterations in dogs during cervical myelography using ioversol

Subarachnoid infusion of most contrast mediums and the steps involved in performing a cervical myelography have adverse affects that can discourage its use in the radiographic diagnosis of spinal cord diseases. Thus, the cardiovascular and respiratory alterations associated with neck flexion, subarachnoid puncture, and cerebrospinal fluid drainage during subarachnoid infusion of ioversol (320mgI/mL) in dogs under general anesthesia using isoflurane were evaluated. The dogs received subarachnoid infusion of autologous cerebrospinal fluid kept at 38°C - control group (GC); ioversol 0.3mL/kg at 25°C (GI25) and ioversol 0.3mL/kg heated to 38°C (GI38). Each dog had its heart rate (HR), systolic arterial pressure (SAP), diastolic arterial pressure (DAP), respiratory rate (RR), oxyhemoglobin saturation (SaO2) and electrocardiography readings (PR and QT intervals) recorded. Group comparisons showed no statistical difference regarding neck positioning, subarachnoid puncture, and subarachnoid infusion of contrast medium on HR, RR and SaO2, cardiac rhythm or conduction. However, isoflurane significantly increased PR and QT intervals. Based on these findings, it is concluded that the steps involved in cervical myelography and the use of ioversol 320mgI/mL at 0.3mL/kg (25ºC and 38ºC) during cervical myelography did not result in relevant cardiovascular and respiratory alterations, except for an elevation in arterial pressure after injection of ioversol.

Spinal Cord Disease in Patients With Cancer

Spinal cord disease is not uncommon in patients with systemic cancer. Most cases are due to epidural tumor metastases with resulting cord compression, although intramedullary spinal cord metastases, radiation myelopathy, and myelopathic complications of chemotherapy must be considered. Techniques for surgical decompression of the spinal cord in patients with epidural tumor have improved significantly over the past decade. Several studies have demonstrated improved neurologic outcome in a subset of patients with epidural spinal cord compression treated surgically. This article outlines the clinical features, radiographic findings, and differential diagnosis of spinal cord disease in patients with cancer and describes the therapeutic approach to these patients. Early identification and treatment of patients with epidural spinal cord compression is critical to maintaining neurologic function and preserving quality of life.

Screening of occult spinal dysraphism by ultrasonography

Ultrasonography for diagnosis of spinal cord diseases has been used since the eighties. There are different fields for its use: traumatic spine lesions, intra-operative use in trauma and spine tumors surgery, pre-operative and follow up study for spinal dysraphism, occult spinal dysraphism of the newborn. Patients with suspected occult spinal dysraphism are the most important indication for the method. Ultrasonography was performed in 292 patients of Hospital das Clínicas, Universidade Federal de Minas Gerais. Lesions such as conus medullaris lipomas, low level of conus medullaris, filum terminale tethering, cauda equina cysts and dermal sinuses can be well demonstrated. There is no difficulty in interpreting the image. The exam does not need sedation; it is safe, fast and cheap. Ideally it should be performed by the neurosurgeon as it may provide many information during the examination. The ultrasonography does not replace magnetic resonance imaging but it is an excellent method for screening.

Feasibility of a Diffusion Sequence to Investigate the Spinal Cord

Diffusion weighted imaging (DWI) may represent a valuable tool in the early diagnosis of spinal cord diseases. The purpose of this paper was to test the feasibility of a single shot fast spin echo (SSFSE) DWI in normal and abnormal spinal cord, and to evaluate its use in routine clinical imaging. We used a SSFSE sensitive to diffusion (b = 600 s/mm2) with multi-slice or single slice technique to study normal (32 cases) or abnormal (39 cases) spinal cords. Apparent diffusion coefficient (ADC) maps were calculated. Single slice sequences were significantly more reliable than multi-slice sequences for measurement of ADC. In normal subjects, mean ADC values were remarkably similar at both cervical and thoracic levels. Increased ADC values were detected in patients with cord trauma, myelitis, dural malformation, glioma, syringomyelia or metastasis, whereas decreased ADC values were detected in a patient with cervical intraspinal metastasis. This is the first report of the feasibility of a single slice SSFSE diffusion sequence for routine spinal cord imaging. The measurement of ADC may be of diagnostic value for the insight it offers on the pathophysiology of parenchymal damage.

MRI diagnosis of spinal cord diseases

MRI diagnosis of spinal cord diseases

Vascular neoplasms and malformations, ischemia, and hemorrhage affecting the spinal cord: MR imaging findings.

This essay illustrates the imaging spectrum of vascular neoplasms and malformations, ischemia, and hemorrhage affecting the spinal cord. Most of these abnormalities occur far more frequently in the brain. The goal of this essay is to provide a sound anatomic and radiologic basis for the evaluation of these diseases. Knowledge of the unique cross-sectional anatomy, blood supply, and venous drainage of the spinal cord is essential in understanding the radiographic appearance of certain vascular lesions. The superior spatial resolution of fast spin-echo pulse sequences and improvements in MR angiography have expanded the role of MR imaging in the diagnosis of spinal cord diseases. These techniques are emphasized in this essay, and potential diagnostic pitfalls are highlighted. The diseases illustrated are grouped in the categories of enlarged vessels, ischemia, and hemorrhage.

Magnetic Resonance Imaging of Spinal Cord Disease of Childhood

Correct diagnosis of spinal cord disease in childhood is often delayed, resulting in irreversible neurologic deficits. A major reason for this delay is the lack of a reliable means to noninvasively visualize the spinal cord. Magnetic resonance imaging (MRI) should be useful in the evaluation of diseases of the spinal cord. A 1.5 Tesla MRI unit with a surface coil was used to study 41 children, including eight patients with intrinsic spinal cord lesions, eight patients with masses compressing the cord, 12 patients with congenital anomalies of the cord or surrounding bony structures, three patients with syrinxes, and three patients with vertebral body abnormalities. Intrinsic lesions of the cord were well seen in all cases as intrinsic irregularly widened, abnormally intense cord regions. MRI was helpful in following the course of disease in patients with primary spinal cord tumors. Areas of tumor were separable from syrinx cavities. Extrinsic lesions compressing the cord and vertebral body disease were also well visualized. Congenital anomalies of the spinal cord, including tethering and lipomatous tissue, were better seen on MRI than by any other radiographic technique. MRI is an excellent noninvasive "screening" technique for children with suspected spinal cord disease and may be the only study needed in many patients with congenital spinal cord anomalies. It is also an excellent means to diagnose and follow patients with other forms of intra- and extraspinal pathology.

Magnetic resonance imaging in the diagnosis of spinal cord diseases.

Experience with magnetic resonance imaging in 22 patients with diseases of the spinal cord is reported. Important additional diagnostic information as compared to conventional neuroradiological techniques (myelography, spinal CT) was gained especially in cases of hydrosyringomyelia, intraspinal tumour and multiple sclerosis. It is suggested that magnetic resonance imaging may become the method of choice in the diagnosis of structural spinal cord diseases.

Diagnosis of spinal cord disease

Diagnosis of spinal cord disease