Spinal Sonography Research Articles

Application of intraoperative spinal ultrasonography in cervical laminoplasty

To investigate the clinical value of intraoperative ultrasonography in cervical laminoplasty. Thirty patients underwent cervical laminoplasty for cervical compressive myelopathy in our hospital from April 2010 to April 2012. Spinal cord compression ratio was calculated in preoperative MRI axial images for every patient. The spinal cord decompression status was evaluated by intraoperative ultrasonography during cervical laminoplasty. The pre- and post-operative Japanese Orthopaedic Association Scoring System (JOA) score was recorded, and the recovery ratios of surgery were graded using the Hirabayashi equation. The relationship between the parameters and neural recovery was explored. The intraoperative ultrasonography was used to evaluate the ventral compression of the spinal cord. The ultrasonographic dynamic viewings were classified into three types based on the spinal cord contact with ventral structures after decompression: Type 1, non-contact (n=2); Type 2, contact and apart (n=16); and Type 3, contact (n=12). The patients were divided into two groups: group A, showing Type 1 or 2 findings, representing satisfied decompression; and group B, showing Type 3 findings with insufficient decompression. The recovery ratio was (73.3±21.0)%(31.3%-100.0%) in group A, but decreased to (43.2±33.1)%(0-83.3%) in group B(t=3.05,p=0.005). Pearson analysis showed that the patient age(r=-0.294,p=0.122), preoperative JOA score(r=0.059,p=0.759), and spinal compression ratio(r=0.269,p=0.151) was not correlated with Hirabayashi recovery ratio. Intraoperative ultrasonography during laminoplasty is a feasible and promising method for evaluating spinal cord decompression status and predicting the prognosis following surgery.

Spine Ultrasonography: Interventions and Diagnostics

SUMMARYUltrasound-guided procedures are well established and utilized in the regional anesthesia and radiology practice. Conversely, there have been considerable difficulties in implementation of ultrasound in pain medicine. Ultrasonography has to compete with the more established modalities such as fluoroscopy and computed tomography; however, ultrasound has the advantage of radiation safety and point-of care imaging. It also allows direct visualization of tissue planes, blood vessels and nerves. Ultrasound-guided spine interventions are technically feasible and reasonably accurate when validated with conventional radiological modalities. Epidural, zygapophysial joint and caudal injection techniques have been published. The main pitfall of the ultrasound-guided spinal procedures lies in the inability to diagnose intravascular injections. Future technological improvements will help to solve this problem. Diagnostic spinal sonography may also contribute to the practice of medicine helping in the clinical workup of scoliosis and paraspinal pathology.

Application of intraoperative spinal ultrasonography in thoracic spinal decompressive operations

To investigate the feasibility and clinical value of intraoperative ultrasonography (IOUS) in thoracic spinal decompression surgery. Ten patients with confirmed thoracic spinal stenosis underwent thoracic spinal decompression in our center from August 2009 to December 2010. The appearance of the compressed section of spinal cord was observed with IOUS. Before and after the decompression operation, the diameters of dural sac and the spinal cord were recorded respectively. The location and nature of the compression-causing mass were confirmed. IOUS clearly showed the shape of the normal and the compressed sections of dural sac and spinal cord. In the 14 thoracic spinal cord sections of these 10 patients, the anteroposterior diameter, horizontal diameter, and their ratio were bigger than those before decompression. The values of anteroposterior diameter and anteroposterior/horizontal diameter ratio showed significant differences(the P value of dural sac anteroposterior diameter comparison was 0.008, which of spinal cord was 0.007; the P values of these two structures ratio comparison were both 0.002 before and after decompression), while the horizontal diameter presented no significant differences (the P values of both structures were 0.270 and 0.195 respectively before and after decompression). IOUS can clearly show the morphological changes of the dural sac and spinal cord before and after the decompression. In addition, it helps surgeons to locate and specify the nature of the compression-causing mass on the ventral side of dural sac. Furthermore, IOUS can suggest whether the decompression is sufficient in a real-time manner.

Assessment of a single-operator real-time ultrasound-guided epidural technique in a porcine phantom

To the Editor, Recent correspondence in the Journal highlighted the usefulness of a porcine carcass phantom for teaching and learning ultrasound-guided paravertebral techniques because of the notable similarity of spinal and paravertebral structures in pigs and humans. We have previously described a method of deodorizing and curing a porcine model for lumbar sonoanatomy. We have now used the porcine model to assess the feasibility of a singleoperator ultrasound-guided epidural technique. The phantom was a T12-L5 section of pork spine with associated musculature cured in 66% alcoholic gel (Aqium Gel, Ego Pharmaceuticals Pty Ltd, Australia). The Sir Charles Gairdner Group Human Research Ethics Committee approved the project (No. 2010-179), and all participants gave written informed consent. Ten anesthesiologists were recruited who were experienced in ultrasound-guided regional anesthesia but were non-expert in spinal sonography. They were shown a technique of paramedian epidural insertion using ultrasound assistance (Sonosite M-Turbo, 13-8 MHz linear array, Bothel, WA, USA) with a 17G echogenic Tuohy needle (Pajunk TuohySono, Geisingen, Germany) and an Epidrum device (Exmoor Innovations, UK) that provides visual confirmation of loss of resistance (LOR) when the air-filled diaphragm deflates. The Tuohy-Epidrum-syringe assembly was introduced in-plane from the caudal end of the transducer, and the needle was advanced until the tip approached the ligamentum flavum. At this point, the Epidrum device was inflated (Figure). Deflation occurred as the needle tip entered the epidural space, and the Epidrum and syringe were removed. The primary endpoint was successful threading of the catheter and appearance in the epidural space at the cephalad end of the phantom. Each anesthesiologist performed the task twice. Their attempts were recorded and timed by one of the authors (S.B.). Participants made a subjective assessment of the technique using a structured questionnaire. Secondary endpoints included time taken from needle first on view to visual LOR and percentage of time the needle was in view. The catheter was threaded successfully in 19 out of 20 attempts. One failure occurred due to premature Epidrum deflation prior to the needle entering the epidural space. This was clearly imaged but protocol dictated an attempt at catheter insertion. Mean (standard deviation) time to LOR was 51 (27) sec. The needle was visible 90 (10)% of the time corresponding with 90% of participants assessing visibility as excellent on a three-point rating scale. The task was evaluated as easy or intermediate by 60% of participants. While the other 40% of participants performed equally well, they expressed their natural caution over a new technique that others have labelled as ‘‘advanced’’. All participants would consider performing the technique on a patient, which suggests that phantom practice allowed participants to gain confidence that could result in changes to clinical practice. The echogenic TuohySono overcame the needle visibility difficulties at steep insertion angles that have previously been highlighted. Stiffness of the Tuohy allowed the needle rather than the transducer to be manipulated to preserve an in-plane view. The stationary transducer maintained an optimal image of the target at all times. The Epidrum made a single-operator Parts of the data have been presented as a poster at the Australian New Zealand College of Anaesthetists Annual Scientific Meeting in Hong Kong, May 2011.

Gelatin-Agar Lumbosacral Spine Phantom

This report describes the preparation of a gelatin-agar spine phantom that was used for spinal sonography and to practice the hand-eye coordination skills required to perform sonographically guided central neuraxial blocks. The phantom was prepared by embedding a lumbosacral spine model into a mixture of gelatin and agar in a plastic box. Cellulose powder and chlorhexidine were also added to the mixture, after which it was allowed to solidify. Sonography of the osseous elements of the lumbosacral spine in the phantom was then performed, and their sonographic appearances were compared to those in volunteers. Simulated real-time sonographically guided paramedian spinal needle insertions were also performed in the phantom. The texture and echogenicity of the phantom were subjectively comparable to those of tissue in vivo. The osseous elements of the spine in the phantom were clearly delineated, and their sonographic appearances were comparable to those seen in vivo in the volunteers. During the simulated sonographically guided spinal injections, the needle could be clearly visualized, but the phantom provided little tactile feedback. In conclusion, the gelatin-agar spine phantom is a simple and inexpensive sonographic spine model that has a tissuelike texture and echogenicity. It can be used to study the osseous anatomy of the lumbar spine and practice the skills required to perform sonographically guided central neuraxial blocks.

Sonographic Findings in a Neonate With Diastematomyelia and a Tethered Spinal Cord

Congenital midline cutaneous paraspinal lesions, mostly located in the lumbosacral areas, are widely recognized as markers of occult spinal dysraphism. Diastematomyelia, or a split spinal cord, is an unusual congenital spinal abnormality in which the spinal cord is divided into 2 columns by a fibrous, cartilaginous, or bony septum. In most cases, lesions are located on the lower thoracic and upper lumbar parts of the spine. It often manifests in the neonatal period with midline paraspinal lesions. Sonography is a reliable tool for the study of the most severe spinal dysraphism. Diastematomyelia has been reported in neonates; however, to the best of our knowledge, the sonographic findings of diastematomyelia have rarely been described. We report a case of diastematomyelia and a tethered spinal cord in a neonate with lower back hemangioma at birth that was diagnosed via spinal sonography and was confirmed by spinal magnetic resonance imaging (MRI).

Spinal dysraphism with anorectal malformation: lumbosacral magnetic resonance imaging evaluation of 120 patients

Purpose We evaluated the prevalence of spinal dysraphism (SD) in patients with anorectal malformation (ARM) by magnetic resonance imaging (MRI). Methods From January 2002 to March 2009, 120 patients with ARM who underwent anorectal reconstruction were evaluated for SD with sacral plain film, spinal ultrasonography (US), and lumbosacral MRI. We adopted Krickenbeck international classification of ARM. Results Spinal dysraphism was present in 41 (34.2%) of 120 patients with ARM, 3 (13.0%) of 23 patients with perineal fistula, 7 (29.2%) of 24 patients with vestibular fistula, 4 (36.4%) of 11 patients with rectovesical fistula, 18 (40.9%) of 44 patients with rectourethral fistula, and 9 (60.0%) of 15 patients with cloacal anomaly ( P = .04). Among 41 patients having SD detected by MR, 26 patients (26/41; 63.4%) underwent detethering surgery for tethered spinal cord. The mean sacral ratio (SR) in patients who underwent detethering surgery (0.54 ± 0.19) was significantly lower than in patients who did not undergo detethering surgery (0.69 ± 0.13; P < .001). The optimal cutoff for the SR value predicting SD requiring detethering surgery was 0.605, with sensitivity of 65.4% and specificity of 77.7%. Conclusions Spinal dysraphism is common in patients with ARM, and its prevalence is higher in patients with complex ARM. Spinal anomalies can occur even with benign types of ARM and, therefore, that all patients should be screened. Magnetic resonance imaging is useful in detecting occult SD that may be missed by conventional radiologic evaluation, physical examination, and spinal US. We further recommend a lumbosacral MRI examination in those whose SR is lower than 0.6.

Lower Lumbosacral Cutaneous Lesion in a Newborn

A term newborn has a cutaneous lesion in the lower lumbosacral region. ### Prenatal History ### Birth History ### Physical Examination ### Imaging ### Cutaneous lesion in lower lumbosacral region ### Occult Spinal Dysraphism On postnatal day 2, magnetic resonance imaging (MRI) of the spine was performed, but results were limited due to motion artifact. A tethered cord was suspected. Repeat MRI on postnatal day 4 confirmed a tethered cord that progressed into a terminal lipoma. An associated sacrococcygeal deformity also was noted. Know the indications …

Spinal sonography in term neonates with cutaneous markers of occult spinal dysraphism: Results of our experience

Occult spinal dysraphism (OSD) refers to skin-covered lesions, characterized by incomplete fusion of the midline mesenchymal, bony or neural elements of the spine. 3–8% of the infants with cutaneous markers in the lumbo-sacral region have an underlying OSD. We report the occurrence of OSD in neonates with congenital midline lumbosacral cutaneous markers. Over a 3 year period, 240 neonates (125 m/115 f) were scanned between the first day of life and the ninth week (m: 54 days) with a high resolution linear transducer (7.5 MHz). Data collected included: indication for ultrasound examination (US), date of birth, date of US, age at US, findings of antenatal US and other findings where relevant. Abnormalities had already been detected antenatally in two cases. In 10/240 examined neonates (4.1%) we observed: spinal lipoma (n° 3) lipomyelomeningocele (n° 2), lipomyelocele (n° 1), meningocele (n° 1) lumbar dermoid cyst (n° 2), and hydromelia (n° 1). In 6/10 newborns (60%) with OSD there was a combination of two or more different skin lesions. In all infants, it was confirmed by MRI imaging. Surgical correction was performed at the end of the first year of life (m: 5 m). MRI is the gold standard of screening for OSD, but it is time consuming, costly and invasive. US revealed an effective, non invasive, inexpensive screening method, useful to detect OSD as long as the vertebral arch region is not completely ossified. A combination of 2 or more congenital midline skin lesions constitutes the strongest marker of OSD.

Surgery of Spinal Tumors

J. Klekamp and M. Samii, eds. Springer; 2007, 526 pages, 1862 illustrations, $389.00. Neuroradiologists infrequently observe the intraoperative findings of patients whose imaging studies they have interpreted unless they are actively involved with intraoperative spinal sonography (which comprises

The "Water-based Spine Phantom"? - A Small Step Towards Learning the Basics of Spinal Sonography

The "Water-based Spine Phantom"? - A Small Step Towards Learning the Basics of Spinal Sonography

Intraoperative Spinal Sonography

Intraoperative Spinal Sonography

Ultrasonography of the spine in infancy

Based on a standardized technic and reliable attachment of the presented structures the suitability of spinal sonography as a screening-method in newborns and infants should be estimated. Enabled by the comparison of sonographic transverse and sagittal plains with identical anatomic sections of an infant corpse the anatomic structures of an healthy spine were associated, which was verified in the clinical use later on. Exemplary photographs of a collective of 50 newborns and infants reproduce the presentation of the spine found in the preparation of the corpse. The technical practicability of such an examination in clinical use was confirmed herein and it became clear that the application of this method is limited from the 6.-8. months of living on because of the increasing ossification which involves a reduction of the image quality. The deviations from the spine presentation in normal relations were shown by some ultrasound examples of malformed spines (spinal dysraphism, hemivertebrae). Reproducible attachment of the structures obviously seen with ultrasound and the clear demarcation of deformations as well as the simply practicable examination make evident the suitability of spinal sonography in newborns and infants as a noninvasive screening for the exclusion of spine malformations.

Intraoperative Ultrasonography of the Spinal Cord in Acute Spinal Cord Injury

Objective. To analyze application of intraoperative ultrasonography and Doppler ultrasonography in patients with acute spinal cord injury. Material and Methods. A complex of intraoperative ultrasonography examinations was performed in 10 patients before and after spinal cord decompression to study pathological structural and hemodynamic lesions. Dura mater, subdural space, liquor, spinal cord, roots of the spinal cord and cauda equina were studied. Color Doppler mapping and ultrasonic duplex scanning were used to identify the arterial and venous vessels of the spinal cord, their anatomic features, linear and volume velocities of the blood flow, resistive and pulsate indices. Doppler ultrasonography of spinal cord vessels included assessment of Doppler spectrum shape, velocity and resistive parameters of the blood flow in the spinal artery. Results. Complex ultrasonic visualization examinations reliably detected spinal cord compressions, cysts, hematoma, contusion foci and subdural hemorrhages. A vascular mode revealed spinal artery occlusion and stenosis, hyper- and hypoperfusion of spinal vessels, reduced blood flow and venous dyscirculation. Conclusion. Thus, methods of complex intraoperative spinal cord ultrasonography are found to be very effective for evaluation of local structural and hemodynamic disturbances caused by spinal cord injury. These ultrasonic techniques are simple in use, highly informative, and comparable with MRI data. These ultrasonic techniques may be recommended for wide application in acute spinal cord injury diagnostics.

Spinal Sonography in Infants with Cutaneous birth Markers in the Lumbo-Sacral Region – an Important Sign of Occult Spinal Dysrhaphism and Tethered Cord

Cutaneous markers in the lumbo-sacral region are indicators of occult spinal dysrhaphism and tethered cord. By means of spinal sonography, anatomical abnormalities of the spinal cord can be shown in the neonatal period. We report on 6 infants with lumbo-sacral cutaneous abnormalities who were investigated with a high resolution linear transducer (> 7.5 MHz) and a computer sonographic unit (Sequoia, Acuson). The investigations were performed between the first day of life and the ninth week (m: 26 days). The following cutaneous markers could be found: Asymmetrical gluteal crease (4); dermal sinus (2), hairy tuft (1); pigmented naevus (1); cutaneous appendage (1); haemangioma (1); unilateral peroneal paralysis with hypotrophic correspondic leg (1). Sonographic evaluation showed the following abnormalities: Tethered cord (6); diastematomyelia (2); tight filum terminale (2); spinal lipoma (3); lipomyelomeningocele (2), myelocystocele and hydromyelia (1). In all infants, sonographic diagnosis could be confirmed by MR imaging and intraoperatively. Surgical correction was performed at the age of 2 to 12 months (m: 7.7 months). All infants with cutaneous markers in the lumbo-sacral region should be investigated by spinal sonography as long as the vertebral arches are not completely ossified. Sonography of the spinal cord may detect occult spinal dysrhaphism and tethered cord and prevent neurological damage by early surgical correction at the end of the first year of life.

Spinal Sonography in Newborns and Infants - Part II: Spinal Dysraphism and Tethered Cord

Patients with cutaneous markers in the lumbo-sacral region as well as infants with bladder and bowel dysfunction, orthopedic anomalies and progressive neurological dysfunction are at risk for spinal dysraphism and tethered cord. Three types of spinal dysraphism can be distinguished: Type I - open spinal dysraphisms with a non-skin covered back mass; type II - closed spinal dysraphisms with a skin covered back mass; type III - occult spinal dysraphisms without a back mass. All spinal dysraphisms can be associated with a tethered cord, characterized by a low position of the conus medullaris below L3. Type I dysraphisms are meningomyeloceles and myeloceles, which are associated with CHIARI-II malformations characterized by the low position of the cerebellar vermis within the foramen magnum. Type II dysraphisms are lipomyeloceles, lipomyelomeningoceles, posterior meningoceles and myelocystoceles. Lipomeningoceles and lipomyelomeningoceles are characterized by a subcutaneous echogenic mass which communicates with the spinal canal and may cause tethered cord. Posterior meningoceles are, dorsal cystic space occupying lesions without internal neural tissue. Myelocystoceles are characterized by a cystic dorsal mass which communicates with a dilated central canal characteristic of syringo-hydromyelia. Type III dysraphisms without a back mass are frequently associated with cutaneous markers in the lumbo-sacral region. Sonographically dermal sinus tracts, diastematomyelia, tight filum and lipoma of the filum terminale and the caudal regression syndrome have to be distinguished. Dermal sinuses are characterized by an echogenic tract from the skin to the spinal canal, often associated with a spinal dermoid. Diastematomyelia is characterized by a complete or partial duplication of the spinal cord which can only be shown on axial images. Tight filum terminale or lipoma of the filum terminale is characterized by a thick echogenic filum with a diameter of more than 2 mm, and a conus below L3. All different forms of spinal dysraphisms and tethered cord can be diagnosed sonographically in the neonatal period as long as the spinal arches are not completely ossified.

Spinal Sonography in Newborns and Infants - Part I: Method, Normal Anatomy and Indications

Spinal sonography can be performed in newborns and young infants as long as the vertebral arches are not completely ossified. With high resolution linear transducers (>10 MHz), excellent detailed images of the spine may be obtained from the base of the skull to the caudal end of the thecal sac. Sagittal and axial sections are performed routinely. Beside the spinal cord, the dorsal and ventral nerve roots and the cauda equina can be shown. The medullary conus normally ends above the level of L2/L3. Lower positions are suspective of tethered cord. M-mode sonographic examinations reveal oscillations of the cord due to respiration and the pulse cycle. Colour Doppler sonography displays the epidural venous plexus as well as the central branches of the anterior spinal artery. Normal variants are transient widening of the central canal, terminal ventricle and asymmetric nerve roots. Indications for spinal sonography are midline cutaneous markers in the lumbosacral region, subcutaneous masses, foot abnormalities, anorectal and genitourinary malformations and neurological abnormalities of the lower extremities. All these clinical symptoms are suspicious of spina bifida occulta and tethered cord which should be ruled out by spinal sonography.

Extensive Perineal Infantile Hemangioma with Associated Congenital Anomalies: An Example of the PELVIS Syndrome

Extensive Perineal Infantile Hemangioma with Associated Congenital Anomalies: An Example of the PELVIS Syndrome

Neuroimaging in Traumatic Spinal Cord Injury: An Evidence-based Review for Clinical Practice and Research

Objective: To perform an evidence-based review of the literature on neuroimaging techniques utilized in spinal cord injury clinical practice and research.Methods: A search of the medical literature for articles on specific neuroimaging techniques used in SCI resulted in 2,302 published reports. Review at the abstract and full report level yielded 99 clinical and pre- clinical articles that were evaluated in detail. Sixty nine were clinical research studies subjected to quality of evidence grading. Twenty-three articles were drawn from the pre-clinical animal model literature and used for supportive evidence. Seven review articles were included to add an element of previous syntheses of current thinking on neuroimaging topics to the committee process (the review articles were not graded for quality of evidence). A list of clinical and research questions that might be answered on a variety of neuroimaging topics was created for use in article review. Recommendations on the use of neuroimaging in spinal cord injury treatment and research were made based on the quality of evidence.Results: Of the 69 original clinical research articles covering a range of neuroimaging questions, only one was judged to provide Class I evidence, 22 provided Class II evidence, 17 Class III evidence, and 29 Class IV evidence.Recommendations: MRI should be used as the imaging modality of choice for evaluation of the spinal cord after injury. CT and plain radiography should be used to assess the bony anatomy of the spine in patients with SCI. MRI may be used to identify the location of spinal cord injury. MRI may be used to demonstrate the degree of spinal cord compression after SCI. MRI findings of parenchymal hemorrhage/ contusion, edema, and spinal cord disruption in acute and subacute SCI may contribute to the understanding of severity of injury and prognosis for neurological improvement. MRI-Diffuslon Weighted Imaging may be useful in quantifying the extent of axonal loss after spinal cord injury. Functional MRI may be useful in measuring the anatomic functional/metabolic correlates of sensory-motor activities in persons with SCI. MR Spectroscopy may be used to measure the biochemical characteristics of the brain and spinal cord following SCI. Intraoperative Spinal Sonography may be used to identify spinal and spinal cord anatomy and gross pathology during surgical procedures. Further research in these areas is warranted to improve the strength of evidence supporting the use of neuroimaging modalities. Positron Emission Tomography may be used to assess metabolic activity of CNS tissue (brain and spinal cord) in patients with SCI.

Imaging of congenital anomalies and variations of the caudal spine and back in neonates and small infants

Spinal dysraphisms are categorized in open dysraphisms with prominent abnormal nervous tissue above the skinlevel and closed dysraphisms with a skin covered malformation. Especially the occult dysraphisms are marked by suspect skin masses and other dermal anomalies. The purpose of this review is to demonstrate the indications and spectrum of spinal sonography in neonates and infants. In comparison typical dysraphisms are demonstrated in sonography and MR Imaging. We demonstrate the value of ultrasound in comparison to MRI and describe a usefull handling of the methods in neonates and infants. The differentiation between the potentially dangerous dimples associated with dermal sinus, which can lead to meningitis and the harmless coccygeal dimple in the cranial gluteal cleft is presented. An inconspicious examination does not need a further imaging, but suspicious results of sonography need an MR imaging dependent of clinical conditions. Neurologically conspicious infants need MR imaging completed by sonography. Great advantages of sonography are the real time examination and the potential to show oscillations of the conus, filum and cauda equina in M-mode-imaging.