Motion Characteristics of the Functional Spinal Unit During Lumbar Disc Injection (Discography) Including Comparison Between Normal and Degenerative Levels.

OBJECTIVE: While provocation lumbar discography has been used to identify discs responsible for low back pain, the biomechanical effects of disc injection have received little attention. The purpose of this study was to assess the motion of the functional spinal unit including the endplate and facet/pedicle region during disc injection including comparison between normal and degenerative discs. SUBJECTS: Subjects represent 91 consecutive patients referred for discography with chronic low back pain. METHODS: Lateral projection vertebral motion was retrospectively analyzed at 232 levels (normal: 76 [32.8%], degenerative: 156 [67.2%]). Pre- and postinjection fluoroscopic images were size scaled, and lower endplates were superimposed on separate PowerPoint images. Upper endplate and facet/pedicle motion was separately and independently analyzed on toggled PowerPoint images, subjectively graded as prominent, intermediate, questionable/uncertain, or no motion. Disc morphology was graded using the anteroposterior/lateral postinjection disc appearance (Adams criteria). RESULTS: Prominent or intermediate endplate and facet/pedicle motion was identified at most lumbar levels with substantial overall agreement (degenerative: κ = 0.93, 95% confidence intervals [CI] = 0.87-1.00; normal: κ = 0.80, 95% CI = 0.61-1.00). Degenerative levels were strongly associated with a lower degree of endplate and facet/pedicle motion compared with normal: ("prominent" motion grade: endplate: 61% [95/156] vs 89% [68/76], P < 0.001; facet/pedicle: 60% [93/156] vs 88% [67/76], P < 0.001). CONCLUSION: Disc injection expands the disc space inducing endplate motion, pedicle motion, and facet translation in almost all normal and most degenerate levels. Disc injection therefore biomechanically "provokes" the entire functional spinal unit. When provoked pain is encountered during lumbar discography, contribution from the associated facet joint and myotendinous insertions should be considered.

Guideline summary review: an evidence-based clinical guideline for the diagnosis and treatment of low back pain.

BACKGROUND CONTEXT: The North American Spine Society's (NASS) Evidence Based Clinical Guideline for the Diagnosis and Treatment of Low Back Pain features evidence-based recommendations for diagnosing and treating adult patients with nonspecific low back pain. The guideline is intended to reflect contemporary treatment concepts for nonspecific low back pain as reflected in the highest quality clinical literature available on this subject as of February 2016. PURPOSE: The purpose of the guideline is to provide an evidence-based educational tool to assist spine specialists when making clinical decisions for adult patients with nonspecific low back pain. This article provides a brief summary of the evidence-based guideline recommendations for diagnosing and treating patients with this condition. STUDY DESIGN: This is a guideline summary review. METHODS: This guideline is the product of the Low Back Pain Work Group of NASS' Evidence-Based Clinical Guideline Development Committee. The methods used to develop this guideline are detailed in the complete guideline and technical report available on the NASS website. In brief, a multidisciplinary work group of spine care specialists convened to identify clinical questions to address in the guideline. The literature search strategy was developed in consultation with medical librarians. Upon completion of the systematic literature search, evidence relevant to the clinical questions posed in the guideline was reviewed. Work group members utilized NASS evidentiary table templates to summarize study conclusions, identify study strengths and weaknesses, and assign levels of evidence. Work group members participated in webcasts and in-person recommendation meetings to update and formulate evidence-based recommendations and incorporate expert opinion when necessary. The draft guideline was submitted to an internal and external peer review process and ultimately approved by the NASS Board of Directors. RESULTS: Eighty-two clinical questions were addressed, and the answers are summarized in this article. The respective recommendations were graded according to the levels of evidence of the supporting literature. CONCLUSIONS: The evidence-based clinical guideline has been created using techniques of evidence-based medicine and best available evidence to aid practitioners in the diagnosis and treatment of adult patients with nonspecific low back pain. The entire guideline document, including the evidentiary tables, literature search parameters, literature attrition flowchart, suggestions for future research, and all of the references, is available electronically on the NASS website at https://www.spine.org/ResearchClinicalCare/QualityImprovement/ClinicalGuidelines.aspx.

Bevacizumab Therapy for Pilomyxoid Astrocytoma.

Pilomyxoid astrocytoma is a rare tumor of the central nervous system generally found in young children near the hypothalamus. Herein, we report a 19-month-old female infant with a pilomyxoid astrocytoma, who underwent surgery as well as carboplatin and vincristine chemotherapy in an attempt to delay radiation therapy to the brain. Magnetic resonance imaging revealed that the tumor had increased in tumor volume on therapy. Chemotherapy with carboplatin and vincristine was stopped and bevacizumab therapy (10 mg/kg every other week) was initiated. After 15 months of bevacizumab therapy, the patient's tumor was significantly smaller. Bevacizumab therapy was discontinued for 6 months due to stability in tumor size but was resumed after tumor growth was observed. Patient was again placed on bevacizumab therapy with subsequent magnetic resonance imagings revealing a decrease in tumor size.

Vertebral artery position in the setting of cervical degenerative disease: implications for selective cervical transforaminal epidural injections.

Cervical transforaminal epidural injections (C-TfEI) are commonly performed in patients with cervical radiculopathy/pain. C-TfEIs are typically performed without incident but adverse events can occur. Using CT-fluoroscopy-guided C-TfEI, we commonly observe the vertebral artery in proximity to the target injection site. The purpose of this study was to assess the position of the vertebral artery relative to the typical C-TfEI injection point. CT-fluoroscopy-guided C-TfEIs were performed at 70 levels in 68 patients with radiculopathy/neck pain (age range 19-83 yrs, mean 50.6 yrs). Degenerative neural foraminal narrowing at each level was characterized (normal-to-mild, moderate, severe). Vertebral artery position was categorized as: anterior (normal), partially covering neural foramen, complete/near-complete covering the neural foramen. Additional measured variables included angle of needle trajectory, foraminal angle, and whether or not needle trajectory intersected with the vertebral artery. Foraminal vertebral artery covering correlated with severity of foraminal degenerative narrowing (p=0.003). Complete/near-complete covering was seen in: 65% severely narrowed foramina, 30% moderately narrowed foramina and 10% normal/mildly-narrowed foramina. Needle trajectory intersected with the vertebral artery in 30 of 70 injections (46%) by CT-fluoroscopy, frequently associated with shallow (lateral) approaches. Foraminal angle, approximating oblique fluoroscopic technique, suggests needle trajectory intersection with the vertebral artery in 27 of 70 foramina (39%). Vertebral artery position is commonly displaced into the foramen in patients with advanced cervical degenerative disease. Operator awareness of altered vertebral artery position is important for determination of optimal needle trajectory and tip placement prior to injection in patients undergoing C-TfEI.

Posterior reversible encephalopathy syndrome (PRES) with immune system activation, VEGF up-regulation, and cerebral amyloid angiopathy.

The case of a 75-year-old man with a history of lymphoma, recent upper respiratory tract infection, and a protracted course of encephalopathy is presented. Radiologically, findings were consistent with posterior reversible encephalopathy syndrome. A brain biopsy revealed evidence of endothelial activation, T-cell trafficking, and vascular endothelial growth factor expression, suggesting that systemic immune system activation may be involved with triggering posterior reversible encephalopathy syndrome. In addition, underlying cerebral amyloid angiopathy may have contributed to the initial nonclassical edema distribution by compromising autoregulatory blood flow mechanisms.

Posterior reversible encephalopathy syndrome and cerebral vasculopathy associated with influenza A infection: report of a case and review of the literature.

BACKGROUND AND PURPOSE: Influenza A infection can precipitate encephalopathy, encephalitis, or Reye syndrome with the development of cerebral edema in children and is associated with an increased incidence of stroke in adults. The mechanism of these events is poorly understood. Posterior reversible encephalopathy syndrome (PRES) is seen in association with infection/sepsis, and cerebral vasculopathy has been demonstrated in PRES. We describe a case of PRES that develops in association with influenza A. SUMMARY OF CASE: A normotensive 65-year-old woman presented with altered mentation and nausea in the setting of a viral prodromal illness ultimately confirmed as influenza A. Posterior reversible encephalopathy syndrome developed on the second day after admission. Catheter cerebral angiogram documented vasculopathy in PRES-involved regions with areas of focal vessel dilatation and string-of-bead appearance. CONCLUSIONS: The association between influenza A and PRES with documentation of cerebral vasculopathy suggests a common systemic vascular mechanism behind PRES and influenza-related encephalopathic edema and stroke.

Clinical, anatomic, and imaging correlation in spine-related pain: the essential elements.

Successful treatment of a patient's spine-related pain depends on accurate targeting of its location and cause. At a basic level, a focused history and physical examination is essential. Understanding of spine anatomy, in particular, spine innervation, is fundamental. Correlation with preprocedure imaging is important to confirm the suspected location(s) of the pain generator and is helpful in planning the approach for image-guided treatment. Understanding the variations in spine anatomy, subtle imaging features, or correlates of root irritation and factors that can affect the patient's presentation at the time of treatment are also critical to accurate targeting and effective treatment. This section reviews the fundamental elements that play a role in accurate diagnosis of the cause of a patient's spine-related pain. Routine application of these basic principles should aid in the approach to the spine-related pain patient and improve both accurate targeting of a patient's pain generator and the outcomes of image-guided treatment.

Epidural steroid injections and selective nerve root blocks.

Epidural steroid injections and lumbar nerve root block/steroid injection are commonly performed interventional treatments for spine-related pain. These procedures are the foundation of any image-guided spine pain management practice. While more generic and not target-specific, epidural steroid injections are highly effective in a large proportion of patients, including patients with axial pain (neck or low back pain), radiculopathy, or spinal stenosis with neurogenic claudication. When isolated lumbar nerve root irritation is more clearly suspected, transforaminal nerve root blocks can provide useful diagnostic information as well as deliver more specifically targeted steroid treatment. Sustained pain relief can be achieved in a substantial number of patients with both types of procedure. Here we review the clinical indications and technical approach to these fundamental image-guided procedures. Fluoroscopy can be the routine approach to all injections. Computed tomography or computed tomographic fluoroscopy can be used as the primary approach in lumbar epidural or nerve root injections or be used as an alternative technique in unique cases. While the basic technical approach to epidural steroid administration in the cervical, thoracic, and lumbar regions is similar, each region has unique issues that must be addressed.

Treatment of facet and sacroiliac joint arthropathy: steroid injections and radiofrequency ablation.

Facet and sacroiliac joint arthropathy are common, specific causes of low back pain. With a combination of a focused physical examination and image guidance, pain originating from these joints can be accurately targeted and these joints respond well to the direct application of long-acting deposition preparation steroids. When routine steroid treatment of the facet joint is not effective and more advanced treatment is required, denervation of the facet joint through the use of radiofrequency ablation (RFA) is a preferred method. Image guidance is a critical tool in targeting facet joint innervation, performing a central role in the techniques used in both preprocedure testing and the RFA treatment. This article reviews the basic image-guided fluoroscopic and computed tomographic-guided approaches to steroid treatment of the facet and sacroiliac joints and further discusses of the painful facet through RFA.

Interventional assessment of the lumbar disk: provocation lumbar diskography and functional anesthetic diskography.

The diagnosis of diskogenic low back pain (LBP) can be elusive. Physical examination of the lumbar disk is limited and imaging offers few objective clues. While invasive, lumbar diskography is a method available to examine or "provoke" the disk directly and determine if LBP is coming from a disk and which disk(s) is responsible for the pain. Once identified, features of the abnormal disk can be evaluated, including the disk's response to intradiskal local anesthetic and disk architecture as observed on diskography imaging and postdiskogram computed tomography. Response to anesthetic can be correlated with imaging features potentially impacting treatment but can also stand alone as an independent objective marker of diskogenic LBP. Here we review the indications for lumbar diskography and the basic lumbar diskogram procedure. We also review the alternative more advanced technique for studying the anesthetic and mechanical features of the disk, functional anesthetic diskography.

The MR imaging features and clinical correlates in low back pain-related syndromes.

Several distinct clinical syndromes can accompany low back pain in patients with lumbar spine abnormality. Developmental factors and any superimposed degenerative changes determine the size and configuration of the spinal canal, lateral recess, and neural foramen, and can affect the nerve roots. Somatic or referred pain may develop depending on the involved anatomic site and underlying pathology. Many times, but not always, MR imaging findings correlate with the clinical presentation. Combined analysis of the imaging and clinical findings may provide a more accurate and concise approach to the patient with low back pain.

"Recurrent" posterior reversible encephalopathy syndrome: report of 3 cases--PRES can strike twice!

In a retrospective review, 3 (3.8%) of 78 patients developed recurrent posterior reversible encephalopathy syndrome. Underlying clinical conditions included sickle cell disease, antibody-positive autoimmune disease, and allogeneic bone marrow transplantation. Infection (bacterial/viral) was suspected or documented in both episodes in all 3 patients. Evidence of endothelial injury (schistocyte formation and increased lactate dehydrogenase) was documented in all patients, and multiple organ dysfunction syndrome developed during the hospital course of all admissions.

The effect of MR contrast medium dose on pituitary gland enhancement, microlesion enhancement and pituitary gland-to-lesion contrast conspicuity.

INTRODUCTION: The purpose of this study was to compare the differences in gland enhancement, microlesion enhancement and gland-lesion contrast ratio in patient groups in which half-dose (HD), standard-dose (SD) and double-dose (DD) contrast medium was used in pituitary MR imaging. METHODS: Pituitary gland enhancement and microlesion enhancement were measured and gland-lesion contrast ratios were calculated in 18 patients receiving HD (0.05 mmol/kg), 9 receiving SD (0.1 mmol/kg) and 13 receiving DD (0.2 mmol/kg) contrast medium. Gland enhancement and microlesion enhancement over baseline were determined employing DICOM region of interest measurements and compared after normalization to temporal lobe white matter. Contrast ratios and differences were also calculated and compared. RESULTS: Gland enhancement and lesion enhancement were greater with larger contrast medium doses (gland: HD 50%, SD 99%, DD 132%; microlesion: HD 19%, SD 54%, DD 86%). The gland-lesion contrast ratios were similar with the three doses (25.6%), reflecting expected similar fractional contrast medium distributions in spite of different doses. The signal difference between gland and microlesion, therefore, was a fixed percentage of gland enhancement (DeltaS approximately 26%) with greater signal differences with larger contrast medium doses. CONCLUSION: Greater gland-to-lesion signal differences with larger contrast medium doses would likely improve pituitary microlesion visualization and margin characterization aiding in microlesion detection as well as preoperative planning.

Severe thoracic kyphosis in the older patient in the absence of vertebral fracture: association of extreme curve with age.

BACKGROUND AND PURPOSE: Limited data exist on the natural history of thoracic kyphosis in elderly patients. The purpose of this study was to determine the statistical distribution of the thoracic kyphotic angle (TKA) measurement in older patients without vertebral body abnormalities when compared with a young population. METHODS: The TKA was measured by Cobb angle on digital lateral chest radiographs in 90 patients >65 years of age, 60 patients 51-65 years of age, 67 patients 36-50 years of age, and 63 patients 18-35 years of age. Patients with vertebral compression, vertebral body angulation, congenital anomaly, or significant scoliosis were excluded. RESULTS: In patients >65 years of age, average TKA was 41.9 degrees , but the distribution was unexpectedly bimodal, with a low mode at 28.3 degrees and an upper mode at 51.5 degrees (P < .001). Elderly women and men independently demonstrated a bimodal TKA distribution. Two-thirds of elderly women and half of elderly men had a TKA >40 degrees (upper mode). In young patients, average TKA was 26.8 degrees . In middle-aged patients, TKA was intermediate and nonbimodal. CONCLUSION: The TKA distribution in elderly patients (>65 years) without vertebral body abnormality is unexpectedly bimodal (non-normal distribution) with a subpopulation of patients significantly more affected by extreme kyphosis. Extreme thoracic kyphosis therefore occurs independently in a large subset of people, in the absence of vertebral wedge compression. The development of extreme thoracic kyphosis might contribute to excess biomechanical stress in the spine and may identify a population at risk for future vertebral compression fracture in particular at the thoracolumbar junction.

Variable incidence of cyclosporine and FK-506 neurotoxicity in hematopoeitic malignancies and marrow conditions after allogeneic bone marrow transplantation.

INTRODUCTION: This study examines whether malignant disease under treatment influences the incidence of cyclosporine or FK-506 neurotoxicity after myeloablative conditioning and allogeneic bone marrow transplantation (allo-BMT). METHODS: Review of 290 patients who received myeloablative conditioning prior to allo-BMT and cyclosporine/FK-506 identified 21 (7.2%) patients with neurotoxicity confirmed by computed tomography or magnetic resonance. Underlying malignancy necessitating allo-BMT included leukemias (67%), lymphoma (10%), myelodysplastic syndrome (10%), and multiple myeloma (MM). Frequency of neurotoxicity by disease was compared. RESULTS: The highest incidence of neurotoxicity was present with MM (25%), whereas the lowest incidence was present with lymphoma (2.7%). Other diseases demonstrated intermediate incidence, including acute leukemias (10%), myelodysplastic syndrome (6.4%), and chronic myelogenous leukemia (4.9%). CONCLUSION: Cyclosporine/FK-506 neurotoxicity varied according to the underlying malignancy. The variable susceptibility to the development of neurotoxicity in this population may depend on the interaction of host vasculature with disease specific factors. Understanding the cause of neurotoxicity could improve survival after allo-BMT.

Cervical diskography performed with a "prong deflector" for improved access to the cervical disk spaces.

The "prong deflector" tool improves accuracy and ease of access to the cervical disk spaces for use in cervical diskography. The tool allows control, deflection, and stabilization of vital neck structures (carotid artery, thyroid cartilages and pharynx) while allowing fluoroscopic visualization during needle insertion without direct operator radiation exposure. Use of the prong deflector resulted in marked reduction of fluoroscopy per cervical level studied because of more rapid access to disk space.

Incorrect needle position during lumbar epidural steroid administration: inaccuracy of loss of air pressure resistance and requirement of fluoroscopy and epidurography during needle insertion.

Loss of air pressure resistance leads to a high rate (25.7%) of inaccurate needle-tip placement in the posterior soft tissues of the back during lumbar epidural steroid administration employing a 20-gauge Tuohy needle. Imaging and epidurogram are essential for confident identification of the lumbar epidural space to enable accurate location of steroid administration. Studies assessing efficacy of lumbar epidural steroid injection and individual patient treatments should ensure location of administration with epidurogram to enhance the validity of results.

Pretransplantation conditioning influence on the occurrence of cyclosporine or FK-506 neurotoxicity in allogeneic bone marrow transplantation.

BACKGROUND AND PURPOSE: Transplantation conditioning regimens have been shown to affect the brain imaging appearance in patients with cyclosporine or FK-506 neurotoxicity. We assessed whether the occurrence of neurotoxicity was affected by the choice of conditioning regimen used before allogeneic bone marrow transplantation (allo-BMT). METHODS: An allo-BMT was performed in 290 patients conditioned before transplantation with myeloablative therapy. Neurotoxicity from cyclosporine or FK-506 developed in 21 (7.2%) of these patients, as confirmed with CT or MR imaging. Two hundred seventy-four (94%) of these 290 patients were conditioned with minor variations of one of five fundamental regimens: cyclophosphamide (Cy)/busulfan (n = 97), Cy/total body irradiation (TBI) (n = 122), Cy/thiotepa/TBI (n = 40), bischloroethylnitrosourea/etoposide/cytarabine/melphalan, or BEAM (n = 10), and Cy/thiotepa/busulfan (n = 5). The remaining 16 patients were prepared with variable regimens. The rates of occurrence of cyclosporine or FK-506 neurotoxicity relative to these conditioning regimens were compared. RESULTS: The lowest rate of cyclosporine or FK-506 neurotoxicity was found in those patients conditioned with Cy (2 days)/busulfan (4 days) (5.1%) or Cy (2 days)/TBI (4 days) (5.9%). Rate of neurotoxicity increased with lengthier conditioning regimens. A high rate of neurotoxicity was present in those patients conditioned with Cy (4 days)/TBI (4 days) (13.7%), and this was statistically significant (P <.05) when compared with Cy (2 days)/busulfan (4 days). CONCLUSION: The rate of occurrence of cyclosporine or FK-506 neurotoxicity varies with the conditioning regimen used, with lengthier regimens associated with a higher rate of neurotoxicity. As the length of the conditioning regimen equates to the total dose of chemotherapy administered, it suggests that the intensity of the regimen is correlated to the predisposition to neurotoxicity from cyclosporine or FK-506.