Arachnoiditis ossifications in the spine / Aracnoidite ossificante na coluna vertebral / Aracnoiditis osificante en la columna vertebral

ABSTRACT Introduction: Arachnoiditis ossificans (AO) in the spine is a rare entity characterized by progressive calcification of the arachnoid and dural sac, with consequent neurological involvement. Objective: Review the causes, clinical manifestations, and complementary studies for their correct diagnosis. Method: Systematic review under PRISMA guidelines, with search in Pubmed, Lilacs, and Embase. Patient demographics (sex and age), history reported as a cause of AO and time elapsed between cause and diagnosis of AO, clinical manifestations, and complementary studies used for diagnosis were collected. Results: 38 articles, of which we collected 46 patients (25 women, 21 men), mean age of 52 years. The most frequent cause was previous spine surgery and myelography with fat-soluble contrast. The most frequent symptoms were insufficient muscle strength (74%) and pain (69%). CT was used in 76%. The most frequent location was thoracic (35%). Conclusion: Its pathogenesis is unclear; described as the final cause of a chronic inflammatory process in the arachnoid with the consequent bone metaplasia. Diagnosis usually precedes a long period of pain and progressive neurological symptoms. The most sensitive and specific complementary study for the diagnosis is the tomography without contrast, which should be requested in case of clinical suspicion. Level of Evidence II; Systematic Review.

Resumo: Introdução: A aracnoidite ossificante (AO) na coluna vertebral é uma entidade rara caracterizada por calcificação progressiva do saco aracnóideo e dural, com consequente envolvimento neurológico. Objetivo: revisar as causas, manifestações clínicas e estudos complementares para o seu correto diagnóstico. Método: Revisão sistemática sob as diretrizes do PRISMA, com busca no Pubmed, Lilacs e Embase. Foram coletados dados demográficos dos pacientes (sexo e idade), história relatada como causa de AO e tempo decorrido entre a causa e o diagnóstico de AO, manifestações clínicas e estudos complementares utilizados para o diagnóstico. Resultados: 38 artigos, dos quais foram coletados 46 pacientes (25 mulheres, 21 homens), com idade média de 52 anos. A causa mais frequente foi cirurgia prévia da coluna vertebral e mielografia com contraste lipossolúvel. Os sintomas mais frequentes foram comprometimento da força muscular (74%) e dor (69%). A TC foi utilizada em 76%. A localização mais frequente foi torácica (35%). Conclusões: Sua patogênese não é clara, é descrita como a causa final de um processo inflamatório crônico na aracnoide com a consequente metaplasia óssea. O diagnóstico é geralmente precedido por um longo período de dor acompanhado por sintomas neurológicos progressivos. O estudo complementar mais sensível e específico para o seu diagnóstico é a tomografia sem contraste, que deve ser solicitada em caso de suspeita clínica. Nível de Evidência II; Revisão sistemática.

Resumen: Introducción: La aracnoiditis osificante (AO) en la columna vertebral es una entidad rara que se caracteriza por la calcificación progresiva de la aracnoides y el saco dural, con la consecuente afectación neurológica. Objetivo: revisar las causas, manifestaciones clínicas y los estudios complementarios para su correcto diagnóstico. Método: Revisión sistemática bajo las directrices PRISMA, con búsqueda en Pubmed, Lilacs y Embase. Se recolectaron los datos demográficos de los pacientes (sexo y edad), el antecedente reportado como causa de AO y el tiempo transcurrido entre causa y el diagnóstico de AO, las manifestaciones clínicas y los estudios complementarios utilizados para el diagnóstico. Resultados: 38 artículos, de los cuales recolectamos 46 pacientes (25 mujeres, 21 hombres), promedio de edad 52 años. La causa más frecuente fue la cirugía previa de columna vertebral y la mielografía con contraste liposoluble Los síntomas más frecuentes fueron la alteración de la fuerza muscular (74%) y dolor (69%). Se utilizó TC en un 76%. La ubicación más frecuente fue torácica (35%). Conclusiones: Su patogenia no es clara, se describe como causa final de un proceso inflamatorio crónico en la aracnoides con la consecuente metaplasia ósea. El diagnóstico generalmente se precede de un largo periodo de dolor acompañado de síntomas neurológicos progresivos. El estudio complementario más sensible y específico para su diagnóstico es la tomografía sin contraste, que debe ser solicitado ante la sospecha clínica. Nivel de Evidencia II; Revisión sistemática.

Spontaneous intracranial hypotension: analysis of 118 patients ' clinical characteristics / 中华神经科杂志

Objective:To summarize the clinical features, radiological characteristics, therapy, and outcome of patients with spontaneous intracranial hypotension (SIH).Methods:The general information, clinical manifestations, auxiliary examinations, treatment, and outcomes in consecutive patients of SIH hospitalized in the Xuanwu Hospital, Capital Medical University from November 2018 to October 2022 were analyzed.Results:A total of 118 patients with a female-to-male ratio of 5∶4 were included and the ages were 17.00-71.00[39.00(34.00,46.75)]years with a preponderance in the age of 30-49 years. Almost all patients had orthostatic headaches (117/118, 99.2%), accompanied by nausea (90/118, 76.3%), vomiting (70/118, 59.3%), neck stiffness (88/118, 74.6%), tinnitus (57/118, 48.3%), and ear fullness (57/118, 48.3%). Brain magnetic resonance imaging (MRI) showed dural enhancement (97/113, 85.8%), enlarged venous sinus (88/113, 77.9%), subdural fluid collection (46/113, 40.7%), decreased suprasellar cistern (86/113, 76.1%), effacement of the prepontine cistern (86/113, 76.1%), diminished mamillopontine distance (80/113, 70.8%). The cerebrospinal fluid (CSF) leaks were detected in 90.7% (107/118) of the patients by magnetic resonance myelography but 54.3% (25/46) and 52.6% (20/38) by CT myelography and magnetic resonance myelography with gadolinium. Lumber puncture found CSF pressure<60 mmH 2O (1 mmH 2O=0.009 8 kPa) in 18.4% (19/103) of patients, increased CSF red blood cell counts in 50.6% (44/87) of patients, CSF pleocytosis in 44.8% (39/87) of patients, increased CSF protein concentrations in 57.5% (50/87) of patients. The headache completely disappeared after conservative treatment in 24.6% (31/118) of patients and after a single targeted epidural blood patch in 89.7% (78/87) of patients. A rebound headache after epidural blood patch treatment occurred in 66.0% (58/87) of patients. Conclusions:The patients with SIH almost manifested with orthostatic headache, and brain MRI and magnetic resonance myelography were suggested in those patients instead of CSF pressure by lumber puncture. Targeted epidural blood patch was effective and safe in SIH patients.

Effects of lumbar myelography on subarachnoid pressure and cardiorespiratory parameters in healthy sheep

ABSTRACT: The purpose of this study was to evaluate the effects of lumbar myelography on subarachnoid pressure, cardiorespiratory parameters and pressure-volume index in sheep. Eight sheep were evaluated. The animals were submitted to puncture of the cisterna magna for monitoring of subarachnoid pressure (SaP). Lumbar myelography was performed through applying Iohexol (0.4mL/kg). ToC, PAS, PAD, MAP, InspISO, FeISO, SaP and CPP were recorded immediately after anesthetic stabilization (M0), during lumbar puncture (M1), and two, four and six minutes after contrast application (M2, M3 and M4, respectively). Blood pressure initially increased, then decreased, returning to basal level, similarly observed for InspISo and FeISo. The SaP rose initially thereafter remaining stable. Despite of the effect on subarachnoid pressure, lumbar myelography can be considered safe in sheep.

RESUMO: O objetivo foi avaliar os efeitos da mielografia lombar na pressão subaracnóidea, parâmetros cardiorrespiratórios e índice pressão-volume em ovinos. Oito ovelhas foram avaliadas. Os animais foram submetidos à punção da cisterna magna para monitoramento da pressão subaracnoidea (SaP). A mielografia lombar foi realizada com a aplicação de Iohexol (0,4mL/kg). Os momentos estudados foram: imediatamente após a estabilização anestésica (M0), durante a punção lombar (M1), dois, quatro e seis minutos após a aplicação do contraste (M2, M3 e M4, respectivamente), para avaliar as seguintes variáveis: ToC, PAS, PAD, MAP, InspISO, FeISO, Sap e CPP. A pressão arterial aumentou inicialmente, depois diminuiu, retornando aos valores iniciais, padrão também observado para o InspISo e o FeISo. O SaP subiu inicialmente, posteriormente, permanecendo estável. A mielografia lombar, apesar de influenciar a pressão subaracnoidea, pode ser considerada segura em ovinos.

Effects of lumbar myelography on subarachnoid pressure and cardiorespiratory parameters in healthy sheep / Efeitos da mielografia lombar na pressão subaracnoidea e nos parâmetros cardiorrespiratórios em ovelhas saudáveis

The purpose of this study was to evaluate the effects of lumbar myelography on subarachnoid pressure, cardiorespiratory parameters and pressure-volume index in sheep. Eight sheep were evaluated. The animals were submitted to puncture of the cisterna magna for monitoring of subarachnoid pressure (SaP). Lumbar myelography was performed through applying Iohexol (0.4mL/kg). ToC, PAS, PAD, MAP, InspISO, FeISO, SaP and CPP were recorded immediately after anesthetic stabilization (M0), during lumbar puncture (M1), and two, four and six minutes after contrast application (M2, M3 and M4, respectively). Blood pressure initially increased, then decreased, returning to basal level, similarly observed for InspISo and FeISo. The SaP rose initially thereafter remaining stable. Despite of the effect on subarachnoid pressure, lumbar myelography can be considered safe in sheep.(AU)

O objetivo foi avaliar os efeitos da mielografia lombar na pressão subaracnóidea, parâmetros cardiorrespiratórios e índice pressão-volume em ovinos. Oito ovelhas foram avaliadas. Os animais foram submetidos à punção da cisterna magna para monitoramento da pressão subaracnoidea (SaP). A mielografia lombar foi realizada com a aplicação de Iohexol (0,4mL/kg). Os momentos estudados foram: imediatamente após a estabilização anestésica (M0), durante a punção lombar (M1), dois, quatro e seis minutos após a aplicação do contraste (M2, M3 e M4, respectivamente), para avaliar as seguintes variáveis: ToC, PAS, PAD, MAP, InspISO, FeISO, Sap e CPP. A pressão arterial aumentou inicialmente, depois diminuiu, retornando aos valores iniciais, padrão também observado para o InspISo e o FeISo. O SaP subiu inicialmente, posteriormente, permanecendo estável. A mielografia lombar, apesar de influenciar a pressão subaracnoidea, pode ser considerada segura em ovinos.(AU)

Proposta de sequenciamento das projeções mielográficas na identificação de compressão da medula espinhal em cães com doença do disco intervertebral cervical / [Sequential proposal in the myelographic views for detection of spinal cord compression in dogs with cervical intervertebral disc disease]

O objetivo deste trabalho foi verificar em quais projeções foi possível identificar compressão da medula espinhal em cães com doença do disco intervertebral (DDIV) cervical e propor um sequenciamento das projeções a ser realizado no exame mielográfico dessa região. Foram avaliadas quatro projeções mielográficas (lateral, ventrodorsal e oblíquas esquerda e direita) de 41 pacientes diagnosticados com DDIV cervical. Em 40 pacientes (97,5%), foi possível identificar compressão da medula espinhal na projeção lateral; em 22 (53,6%), nas oblíquas; e em 11 (26,8%), na ventrodorsal (P<0,05). Havia lateralização da compressão em 22 (53,6%) pacientes; 100% delas (n=22) foram detectadas pelas projeções oblíquas e 50% (n=11) pela ventrodorsal. Em 10 (24,4%) cães, foi observado mais que um local de compressão, tendo as projeções ventrodorsal e oblíquas auxiliado na definição do local de compressão em 50% e 70%, respectivamente. Pode-se concluir que todas as projeções mielográficas estudadas permitem identificar compressão na medula espinhal em cães com DDIV cervical, sendo a incidência lateral a que mais a revelou, seguida das oblíquas e da ventrodorsal, estabelecendo-se, assim, uma proposta de sequenciamento das projeções mielográficas a serem realizadas para essa região.(AU)

The aim of this study was to verify in which of the myelographic views it was possible to identify spinal cord compression in dogs with cervical intervertebral disc disease (IVDD), and to establish a sequence in which myelographic views should be obtained for this region. Four myelographic views (lateral, ventrodorsal, left oblique and right oblique) of 41 patients diagnosed with cervical IVDD were evaluated. In 40 patients (97.5%) it was possible to identify spinal cord compression by lateral view, 22 (53.6%) by the oblique view, and 11 (26.8%) by the ventrodorsal view (P< 0.05). There were lateralized compressions in 22 (53.6%) patients, detected by all oblique views (100%) and by 11 (50%) of the ventrodorsal views. In 10 (24.4%) dogs, more than one compression site was observed, where the ventrodorsal view helped to decide the site in 50% of the cases and oblique in 70%. It can be concluded that all the tested myelographic views allow the identification of spinal cord compressions in dogs with cervical IVDD, the lateral view being the most relevant, followed by the oblique and ventrodorsal view, therefore establishing a sequence of myelographic views should be obtained for this region.(AU)

MRI Spectrum of Symptomatic and Non –Symptomatic Tarlov Cyst: Series of Seven Cases in Orthopaedic Management Point of View

Tarlov cysts are perineural cysts and are usually found in sacral region. The dorsal nerve root is encased in this type of the cyst. These may or may not be with any of the symptomatology. The entity is infrequently found as an incidental finding. These are cerebrospinal fluid (CSF) filled sacs which are diagnosed on cross sectional imaging modalities especially in magnetic resonance imaging (MRI). Tarlov cysts can cause different type of myelopathies as per their location and size. Methods: We present a series of seven cases where these perineural cysts were found during the routine imaging of lumbosacral spine. All these patients had undergone Magnetic Resonance Imaging (MRI) of lumbosacral spine for backache or some other pelvic complaints. In one case Computerized Tomography (CT) Myelography also helped in diagnosis and related bone remodeling.MR myelography adds to the delineation of CSF wrapping around the spinal cord. Results: Three patients were found to be symptomatic and the intensity of complaints corresponded to the size and location of the cysts. In our three cases, the etiopathogenesis also corresponded to the underlying development of these entities. Four patients were asymptomatic as the size of these cysts were small and not contributing to the complaints of the patient. Conclusion: MRI is the best modality to diagnose these perineural cysts which are responsible for different types of myelopathies .T2WI sequences in non contrast MRI studies are the best in delineating the size, shape, outline and location of these cysts. This also further elaborates their extension to the surrounding regions.MR myelography is adjuvant to more morphological features of these cysts.

Myelography and residual contrast in panoramic radiography: case report / Presença de contraste residual de mielografia em radiografia panorãmica: relato de caso

ABSTRACT Myodil or pantopaque is an oil-based contrast solution often used up to 1980 for myelography, cisternography, and ventilography. Oilbased contrasts have a very slow clearance time in the cerebrospinal fluids and may encapsulate for decades and remain in the central nervous system and the interior of the spine. The knowledge of the existence of this rare condition coming from other radiographictests of the past, described in this clinical case, is essential when atypical radiographic images are found.

RESUMO O myodil ou o Pantopaque é uma solução de contraste a base de óleo usada frequentemente até 1980 para mielografia, cisternografia e ventilografia. Os contrastes à base de óleo têm um tempo de liberação muito lento nos fluidos cefalorraquidianos e podem encapsular por décadas e permanecer no sistema nervoso central e no interior da coluna vertebral. O conhecimento da existência dessa condição rara proveniente de outros exames radiográficos do passado, descritos neste caso clínico, é essencial quando são encontradas imagens radiográficas atípicas, principalmente em radiografia panorâmicas.

Application of myelography in diagnosis and therapy of spontaneous intracranial hypotension / 中华神经科杂志

Objective To investigate the application of myelography including digital subtraction angiography myelogram (DSM) and computed tomography myelogram (CTM) in patients with spontaneous intracranial hypotension.Methods The myelography results including DSM and CTM of 10 patients with spontaneous intracranial hypotension form Guangzhou First People's Hospital between January 2013 and June 2018 were retrospectively analyzed.Some patients were treated with targeted epidural blood patch on the basis of myelography.Results Myelography (including DSM and CTM) showed cerebrospinal fluid leakages in all the 10 patients.There were one to 16 leak sites with an average of nine sites (totally 90 leak sites).Forty-two sites (47％) were located in cervical vertebra,19 sites (21％) in thoracic vertebra,22 sites (24％) in lumbar vertebra,and seven sites (8％) in sacral vertebra.On DSM and CTM,cerebrospinal fluid leakage was characterized by the diffusion of contrast agent along one side or the bilateral sides of nerve root,enlargement of the nerve sleeves and paraspinal collections of hyper-demity contrast medium.Two patients whose cerebrospinal fluid leakage occurred in long sections showed more cerebrospinal fluid leakage on CTM than on DSM.Two patients responded well to targeted epidural blood patch on the basis of myelography.The cerebrospinal fluid leakage was completely settled on myelography after the treatment of epidural blood patches.Conclusions Myelography has been shown to assist the diagnosis of spontaneous intracranial hypotension and accurately define the location and extent of cerebrospinal fluid leakages.Myelography can be used to guide targeted epidural blood patch and applied in the reexamination of cerebrospinal fluid leakages after treatment.More cerebrospinal fluid leakages are detected by CTM than by DSM.

Idiopathic Spinal Cord Herniation­Case Report

Idiopathic spinal cord herniation is a rare cause of progressivemyelopathy, especially in the absence of a history of spinal or surgical trauma. The radiological diagnosis ismade through a myelography or an MRI exam. The spinal cord is pushed anteriorly, buffering the dural defect and leading inmost cases to Brown-Séquard syndrome. The present study describes the case of a male patient with a clinical picture of progressive thoracicmyelopathy. In the clinical and radiological investigation, an idiopathic spinal cord herniation on the chest level was identified. During the surgery, the spinal cord was reduced to the natural site, taking its usual elliptical shape, and the dural defect was repaired with a dural substitute. The numbness of the patient improved, and the shocks in the lower limbs disappeared. A postoperative MRI confirmed the surgical reduction of the herniation and the restoration of the anterior cerebrospinal fluid (CSF) column to the spinal cord. The authors describe the clinical, radiological, intraoperative, and postoperative evolution.

Myelography in the Assessment of Degenerative Lumbar Scoliosis and Its Influence on Surgical Management

OBJECTIVE: Myelography has been shown to highlight foraminal and lateral recess stenosis more readily than computed tomography (CT) or magnetic resonance imaging (MRI). It also has the advantage of providing dynamic assessment of stenosis in the loaded spine. The advent of weight-bearing MRI may go some way towards improving assessment of the loaded spine and is less invasive, however availability remains limited. This study evaluates the potential role of myelography and its impact upon surgical decision making. METHODS: Of 270 patients undergoing myelography during 2006–2009, a period representing peak utilisation of this imaging modality in our unit, we identified 21 patients with degenerative scoliosis who fulfilled our inclusion criteria. An operative plan was formulated by our senior author based initially on interpretation of an MRI scan. Subsequent myelogram and CT myelogram investigations were scrutinised, with any additional abnormalities noted and whether these impacted upon the operative plan. RESULTS: From our 21 patients, 18 (85.7%) had myelographic findings not identified on MRI. Of note, in 4 patients, supine CT myelography yielded additional information when compared to supine MRI in the same patients. The management of 7 patients (33%) changed as a result of myelographic investigation. There were no complications of myelography of the total 270 analysed. CONCLUSION: MRI scan alone understates the degree of central and lateral recess stenosis. In addition to the additional stenosis displayed by dynamic myelography in the loaded spine, we have also shown that static myelography and CT myelography are also invaluable tools with regards to surgical planning in these patients.

Using Magnetic Resonance Myelography to Improve Interobserver Agreement in the Evaluation of Lumbar Spinal Canal Stenosis and Root Compression

STUDY DESIGN: Cross-sectional retrospective study designed to assess interobserver agreement. PURPOSE: To investigate if interobserver agreement using magnetic resonance imaging (MRI) in the evaluation of lumbar spinal canal stenosis and root compression can be improved upon combination with magnetic resonance myelography (MRM). OVERVIEW OF LITERATURE: The interpretation of lumbar spinal MRI, which is the imaging modality of choice, often has a significant influence on the diagnosis and treatment of low back pain. However, using MRI alone, substantial interobserver variability has been reported in the evaluation of lumbar spinal canal stenosis and nerve root compression. METHODS: Hardcopies of 30 lumbar spinal MRI (containing a total of 150 disk levels) as well as MRM films were separately reviewed by two radiologists and a neurosurgeon. At each intervertebral disk, the observers were asked to evaluate the thecal sac for the presence and degree of spinal stenoses (mild, moderate, or severe) and presence of root canal compression. Interobserver agreement was measured using weighted kappa statistics. RESULTS: Regarding lumbar spinal canal stenosis, interobserver agreement between the two radiologists was moderate (kappa, 0.4) for MRI and good (kappa, 0.6) for combination with MRM. However, the agreement between the radiologist and neurosurgeon remained fair for MRI alone or in combination with MRM (kappa, 0.38 and 033, respectively). In the evaluation of nerve root compression, interobserver agreement between the radiologists improved from moderate (kappa, 0.57) for MRI to good (kappa, 0.73) after combination with MRM; moderate agreement between the radiologist and neurosurgeon was noted for both MRI alone and after combination with MRM (kappa, 0.58 and 0.56, respectively). CONCLUSIONS: Interobserver agreement in the evaluation of lumbar spinal canal stenosis and root compression between the radiologists improved when MRM was combined with MRI, relative to MRI alone.

Comparison of Root Images between Post-Myelographic Computed Tomography and Magnetic Resonance Imaging in Patients with Lumbar Radiculopathy

OBJECTIVE: To evaluate the diagnostic value of computed tomography-myelography (CTM) compared to that of magnetic resonance imaging (MRI) in patients with lumbar radiculopathy. METHODS: The study included 91 patients presenting with radicular leg pain caused by herniated nucleus pulposus or lateral recess stenosis in the lumbar spine. The degree of nerve root compression on MRI and CTM was classified into four grades. The results of each imaging modality as assessed by two different observers were compared. Visual analog scale score for pain and electromyography result were the clinical parameters used to evaluate the relationships between clinical features and nerve root compression grades on both MRI and CTM. These relationships were quantified by calculating the receiver-operating characteristic curves, and the degree of relationship was compared between MRI and CTM. RESULTS: McNemar's test revealed that the two diagnostic modalities did not show diagnostic concurrence (p<0.0001). Electromyography results did not correlate with grades on either MRI or CTM. The visual analog pain scale score results were correlated better with changes of the grades on CTM than those on MRI (p=0.0007). CONCLUSION: The present study demonstrates that CTM could better define the pathology of degenerative lumbar spine diseases with radiculopathy than MRI. CTM can be considered as a useful confirmative diagnostic tool when the exact cause of radicular pain in a patient with lumbar radiculopathy cannot be identified by using MRI. However, the invasiveness and potential complications of CTM are still considered to be pending questions to settle.

Digital Subtraction Cystography for Detection of Communicating Holes of Spinal Extradural Arachnoid Cysts

OBJECTIVE: The purpose of this study was to demonstrate the usefulness of digital subtraction cystography to identify communicating holes between a spinal extradural arachnoid cyst (SEAC) and the subarachnoid space prior to cyst removal and hole closure. MATERIALS AND METHODS: Six patients with SEAC were enrolled in this retrospective study. Digital subtraction cystography and subsequent CT myelography were performed for every patient. The presence and location of the communicating holes on cystography were documented. We evaluated the MRI characteristics of the cysts, including location, size, and associated spinal cord compression; furthermore, we reviewed cystographic images, CT myelograms, procedural reports, and medical records for analysis. If surgery was performed after cystography, intraoperative findings were compared with preoperative cystography. RESULTS: The location of the communicating hole between the arachnoid cyst and the subarachnoid space was identified by digital subtraction cystography in all cases (n = 6). Surgical resection of SEAC was performed in 4 patients, and intraoperative location of the communicating hole exactly corresponded to the preoperative identification. CONCLUSION: Fluoroscopic-guided cystography for SEAC accurately demonstrates the presence and location of dural defects. Preoperative digital subtraction cystography is useful for detection of a communicating hole between a cyst and the subarachnoid space.

Comparison of spinal MR myelography and Gadolinium MR myelography in localizing spinal cerebrospinal fluid leaks in patients with spontaneous intracranial hypotension / 中华放射学杂志

Objective To compare the diagnostic value between spinal MR myelography (MRM) and intrathecal Gadolinium MR myelography (GdM) in detecting spinal cerebrospinal fluid (CSF) leaks of spontaneous intracranial hypotension (SIH). Methods Retrospective analysis of imaging findings in 158 cases with SIH was performed. Both MRM and GdM were available in 24 cases, and MRM was performed first, followed by GdM within one week. Morphological abnormalities of nerve root, CSF leaks along the nerve roots, and abnormal CSF collections were observed and compared between the two methods by using McNemar statistics and Kappa test statistics. Results Morphological abnormalities of nerve root were detected in 176 lesions on GdM and 163 lesions on MRM, respectively, and GdM was more sensitive in the detection of morphological abnormalities of nerve root (χ2=6.26,P=0.011). CSF leaks along nerve roots were identified in 15 patients on both GdM and MRM while in 5 cases on neither GdM nor MRM, and identified in 4 patients on GdM but not on MRM. CSF leaks along the nerve roots were detected in 67 lesions on GdM and 55 lesions on MRM, respectively, and GdM was more sensitive in the detection of CSF leaks along nerve (χ2=6.05,P=0.012). MRM and GdM showed good consistency(Kappa =0.837,P=0.001)in detecting CSF leaks for patients with SIH. Six and 14 lesions of abnormal CSF collections in bony rims of spines were respectively detected by GdM and MRM, 12 and 28 lesions of abnormal CSF collections in bony rims of the ribs were respectively detected by GdM and MRM. MRM was more sensitive in the detection of abnormal CSF collections in bony rims of the spines and the ribs(χ2=6.13 ,14.06 ,P=0.008 ,0.001). Eleven and 10 lesions of CSF collections in epidural space were respectively detected by GdM and MRM, 1 and 3 lesions of CSF collections of C1—2 retrospinal space were respectively detected by GdM and MRM. No statistically significant differences existed between MRM and GdM in detecting CSF collections of epidural space and C1—2 retrospinal space (χ2=0.01,0.50,P=1.000,0.500). Conclusions MRM and GdM have their respective advantages in detecting spinal CSF leaks along the nerve roots, morphological abnormalities of nerve root and abnormal CSF collections. MRM combined with GdM can provide more information in localizing spinal CSF leaks for patients with SIH.

Imaging Features of Unsuccessful CT Myelography and Gadolinium-enhanced MR Myelography in Spontaneous Intracranial Hypotension / 中国医学影像学杂志

PurposeCT myelography (CTM) and gadolinium-enhanced MR myelography (Gd-MRM) are essential methods used for localizing spinal cerebrospinal fluid leaks in patients with spontaneous intracranial hypotension (SIH) and are significant for diagnosis and guided epidural blood patches. This paper analyzes the rate and imaging features of unsuccessful myelography due to misinjection of contrast into epidural space to guide prompt and correct clinical judgment of unsuccessful myelography.Materials and Methods Myelography from 121 patients with SIH was retrospectively reviewed and the image features of the unsuccessful myelography were analyzed.Results A total of 128 myelography examinations were done. Contrast media was accidently injected into the epidural space in 33 examinations. The failure rate was 25.8%. In all 33 failed exams, bilateral spinal nerve roots on both sides of the dural sac passing through contrast media was observed without visualization of anterior and posterior nerve roots. Cauda equina was not seen within contrast media in 29 cases (87.9%); non-diffusion of contrast media into cisterns and ventricles in 26 cases (78.8%). Contrast was not continuous in spinal canal in 16 cases (48.5%), heterogeneous in 10 cases (30.3%). In 4 cases (12.1%) the inner contour of contrast was not smooth.Conclusion The unsuccessful rate of myelography is relatively high in SIH patients. A prompt and correct decision could be made based on the knowledge of contrast misinjection imaging features.

Outpatient Myelography: A Prospective Trial Comparing Complications after Myelography between Outpatients and Inpatients in Japan

STUDY DESIGN: Prospective comparative study. PURPOSE: To compare the incidence and severity of adverse reactions associated with myelography performed in outpatients vs. in inpatients and report the safety and usefulness of outpatient myelography in Japanese patients. OVERVIEW OF LITERATURE: Myelography is normally performed as an inpatient procedure in most hospitals in Japan. No studies have reported the usefulness and adverse effects of outpatient myelography in Japanese patients. METHODS: We performed 221 myelography procedures. Eighty-five of the 221 patients underwent outpatient myelography using our new protocol. The incidence and severity of adverse reactions were compared with the other 136 patients, who underwent conventional inpatient myelography. We further compared the cost of outpatient and inpatient myelography. RESULTS: The overall rate of adverse effects was 9.4% in outpatients, as compared with 7.4% in inpatients. Overall, 1.2% of outpatients and 0.74% inpatients experienced "severe" adverse effects (requiring hospitalization). There were no significant differences between the 2 groups in either the overall rate of adverse effects or the rate of "severe" adverse effects. Moreover, the average outpatient procedure cost was only one-third to one-half that of the inpatient procedure. CONCLUSIONS: This was the first study to address the safety and usefulness of outpatient myelography in Japanese patients. If selected according to proper inclusion criteria for outpatient procedure, no significant differences were observed in the adverse effects between inpatients and outpatients. The outpatient procedure is more economical and has the added benefit of being more convenient and time-efficient for the patient.

Cardiovascular and respiratory alterations in dogs during cervical myelography using ioversol / Alterações cardiovasculares e respiratórias durante a mielografia cervical com ioversol em cães

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.

Os efeitos adversos provocados pela infusão subaracnoidea de meios de contraste e da mielografia cervical podem desencorajar sua aplicação como alternativa para o diagnóstico radiológico de doenças da medula espinhal. Assim, avaliaram-se os efeitos cardiovascular e respiratório dos procedimentos técnicos necessários à mielografia cervical e da infusão subaracnoidea do ioversol - 320mgI/mL - em cães anestesiados com isofluorano. Foi realizada infusão do líquido cefalorraquidiano autólogo mantido a 38°C - grupo-controle (GC); infusão do ioversol 0,3mL/kg a 25°C (GI25); e infusão do ioversol 0,3mL/kg aquecido a 38°C (GI38). Estudaram-se: pressões arteriais sistólica (PAS) e diastólica (PAD), frequências cardíaca (FC) e respiratória (FR), saturação de oxi-hemoglobina (SaO2) e medidas eletrocardiográficas (intervalos PR e QT). Não houve influência significativa do posicionamento, da punção ou da infusão subaracnoidea do ioversol sobre FC, FR, SaO2, ritmo e condução cardíaca, entretanto o isofluorano aumentou significativamente os intervalos PR e QT. Concluiu-se que a mielografia cervical com ioversol 320mgI/mL, nas temperaturas de 25ºC e 38ºC e na dose de 0,3mL/kg, não causa arritmias cardíacas nem alterações cardiovasculares e respiratórias relevantes, exceto elevação da pressão arterial após a injeção do contraste.

Detection of Surgery-related Spinal Cerebrospinal Fluid Leakage Using Magnetic Resonance Myelography

Detection of cerebrospinal fluid leakage or exact localization of leakage site after spinal surgery is difficult on conventional imaging studies. We report two patients with surgery-related spinal CSF leakage detected on magnetic resonance (MR) myelography. They presented with severe headache after spinal surgeries, lumbar discectomy and excision of spinal meningioma, respectively. The sites of spinal CSF leakage in the patients were detected accurately on MR myelography, and the patients recovered from the postoperative CSF leakage after being treated with an epidural blood patch or reoperation. MR myelography may be effective in demonstrating the exact site of surgery-related spinal CSF leakage.

New Diagnostic Tool for Far Lateral Lumbar Disc Herniation : The Clinical Usefulness of 3-Tesla Magnetic Resonance Myelography Comparing with the Discography CT

OBJECTIVE: To prospectively assess the diagnostic and clinical value of a new technique (3-tesla magnetic resonance myelography, 3T MRM) as compared to computed tomographic discography (disco-CT) in patients with far lateral disc herniation. METHODS: We evaluated 3T MRM and disco-CT of 25 patients, whom we suspected of suffering from far lateral disc herniation. Using an assessment scale, 4 observers examined independently both 3T MRM and disco-CT images. We analyzed observer agreement and the accentuation of each image. RESULTS: We found complete matching, and observer agreement, between high resolution images of 3T MRM and disco-CT for diagnosing far lateral disc herniation. CONCLUSION: We think noninvasive 3T MRM is an appropriate diagnostic tool for far lateral disc herniation as compared to disco-CT.

Intracranial variables in propofol or sevoflurane-anesthestized dogs subjected to subarachnoid administration of iohexol / Variáveis intracranianas em cães anestesiados com propofol ou sevofluorano e submetidos à administração subaracnóidea de iohexol

The effects of subarachnoid administration of iohexol on intracranial hemodynamic in dogs anesthetized with propofol or sevoflurane were evaluated. Thirty adult animals (10.9±2.9kg) were distributed into two groups: PG, where propofol was used for induction (10±0.5mg/kg), followed by a continuous rate infusion at 0.55±0.15mg/kg/hour, and SG, where sevoflurane was administered for induction (2.5 MAC) and for anesthetic maintenance (1.5 MAC). A fiberoptic catheter was implanted on the right superficial cerebral cortex to monitor intracranial pressure (ICP). After 30 minutes, cerebrospinal fluid (CSF) was collected at the cisterna magna and iohexol was injected. The measurements were performed before CSF collection (TA), after the iohexol injection (T0), and at 10-minute intervals (T10 to T60). Intracranial pressure decreased at T0 in SG. Cerebral perfusion pressure at T0 was higher than at TA, T50 and T60 in PG, but in SG, the mean value at T0 was higher than the ones from T20 to T60. Mean arterial pressure at T0 was higher than at TA in PG, while in SG, the values from T20 to T60 were lower than at T0. The heart rate at T60 was lower than at T0 in PG. Cardiac output at TA was lower than at T60 in SG. The cerebrospinal fluid collection and administration of iohexol promoted decrease in intracranial pressure in sevolflurane-anesthetized dogs and increase in cerebral perfusion pressure in propofol-anesthetized dogs.

Avaliaram-se os efeitos da administração subaracnóidea de iohexol sobre a hemodinâmica intracraniana em cães anestesiados com propofol ou sevofluorano. Trinta e dois animais (10,9±2,9kg) foram distribuídos em dois grupos: no GP, o propofol foi usado para indução, 10±0.5mg/kg, seguido por infusão contínua, 0,55±0,15mg/kg/min; no GS, o sevofluorano foi administrado para indução, 2,5 CAM, e manutenção, 1,5 CAM, da anestesia. O cateter de fibra óptica foi implantado na superfície direita do córtex cerebral para monitorar a pressão intracraniana (PIC). Após 30 minutos, o fluido cerebroespinhal (FCS) foi coletado da cisterna magna e o iohexol injetado. As mensurações ocorreram antes da coleta do FCS (TA), depois da injeção de iohexol (T0) e em intervalos de 10 minutos (T10 a T60). A pressão intracraniana diminuiu em T0 no GS. A pressão de perfusão cerebral em T0 foi maior que em TA, T50 e T60 no GP, mas no GS, a média em T0 foi maior que as de T20 a T60. A pressão arterial média em T0 foi maior que em TA no GP, enquanto no GS, de T20 a T60, as médias foram menores que em T0. A frequência cardíaca em T60 foi menor que em T0 no GP. O débito cardíaco em TA foi menor que em T60 no GS. A coleta do fluido cerebroespinhal e a administração do iohexol promoveram a diminuição da pressão intracranina em cães anestesiados com sevofluorano e aumento da pressão de perfusão cerebral em cães anestesiados com propofol.