CT-guided percutaneous cyanoacrylate injection targeting the spinal cerebrospinal fluid leak: a potential therapeutic option for spontaneous intracranial hypotension.

BACKGROUND: We report the first case series of spontaneous intracranial hypotension (SIH) patients who underwent CT-guided percutaneous cyanoacrylate injection targeting the cerebrospinal fluid (CSF) leak. METHODS: A retrospective analysis was performed for all consecutive cases of SIH patients with CSF leak confirmed on CT myelography, treated by CT-guided percutaneous cyanoacrylate injection at our institution from 2016 to 2022. On pretreatment brain and spine MRIs, we analyzed signs of SIH according to the Bern score, and dichotomized cases into positive/negative for spinal longitudinal extradural CSF collection (SLEC-P or SLEC-N). The leaks detected on CT myelography were classified into three types according to Schievink et al. We collected the Headache Impact Test 6 (HIT-6) scores throughout a 6-month follow-up, with a brain CT scan at each visit. RESULTS: 11 patients were included (mean age 48.4 years, six men). Five SLEC-P type 1, three SLEC-P type 2, and three SLEC-N type 3 leaks were identified. All patients had significant signs of SIH on pretreatment brain MRI (mean Bern score 7.8±1.1). Six patients underwent a foraminal puncture, and five patients had a cervical epidural approach. Two patients experienced mild and transient locoregional pain after cervical epidural injection. Mean HIT-6 score at baseline was 66.8±3.2 and at the 6-month follow-up was 38±3.6 (P<0.001). All patients achieved improvement in their symptoms, with 82% of them (9/11) having complete resolution of headaches and SIH findings on CT scans at 6 months. No clinical worsening or recurrence was observed. CONCLUSIONS: CT-guided percutaneous cyanoacrylate injection may be a potential therapeutic option for the different types of CSF leak causing SIH.

Spontaneous absorption of osteophytic calcification associated with chronic dural tear and ventral spinal CSF leak.

Spontaneous intracranial hypotension (SIH) is associated with cerebrospinal fluid (CSF) hypovolemia, often from a traumatic dural tear from a calcified spinal osteophyte. Visualizing osteophytes on CT imaging can guide decision making on candidate leak sites. We report the atypical case of a 41-year-old woman whose ventral CSF leak was associated with an osteophyte that resorbed over an 18-month period. Full workup and treatment were delayed due to unexpected pregnancy and completion of gestational cycle with delivery of a healthy term infant. The patient initially presented with persistent orthostatic headaches with nausea and blurred vision. Initial MRI suggested brain sagging among other findings consistent with SIH. CT myelogram showed an extensive thoracic CSF leak with a prominent ventral T11-T12 osteophyte and multiple small disc herniations. The patient did not respond to epidural blood patches and deferred additional imaging due to her pregnancy. CT myelography performed 5 months post-partum showed an absence of the osteophyte; a follow-up digital subtraction myelogram performed 10 months post-partum showed evidence of source leak at T11-T12 level. T11-T12 laminectomy visualized and repaired a 5 mm ventral dural defect with symptom resolution. This report highlights the potential for a resorbed osteophyte to be the causative agent for long-standing dural tears that do not show visible calcifications on myelography.

A new modified technique of dynamic CT myelography to detect dural tears in spontaneous intracranial hypotension.

We propose a modified dynamic CT-myelography technique for patients with fast CSF leaks caused by ventral dural tears in order to reduce radiation exposure and complications. A fluoroscopy-guided lumbar puncture using an epidural anesthesia kit replaces a CT-guided lumbar puncture, and a smaller volume of less concentrated contrast media is used. This approach has advantages, including speeding up the procedure, reduced radiation exposure, and elimination of the risk of contrast injection into the epidural space.

Postoperative Spinal Cerebrospinal Fluid-Venous Fistulas Associated With Dural Tears in Patients With Intracranial Hypotension or Superficial Siderosis-A Digital Subtraction Myelography Study.

BACKGROUND: Postoperative spinal cerebrospinal fluid (CSF) leaks are common but rarely cause extensive CSF collections that require specialized imaging to detect the site of the dural breach. OBJECTIVE: To investigate the use of digital subtraction myelography (DSM) for patients with extensive extradural CSF collections after spine surgery. METHODS: A retrospective review was performed to identify a consecutive group of patients with extensive postoperative spinal CSF leaks who underwent DSM. RESULTS: Twenty-one patients (9 men and 12 women) were identified. The mean age was 46.7 years (range, 17-75 years). The mean duration of the postoperative CSF leak was 3.3 years (range, 3 months to 21 years). MRI showed superficial siderosis in 6 patients. DSM showed the exact location of the CSF leak in 19 (90%) of the 21 patients. These 19 patients all underwent surgery to repair the CSF leak, and the location of the CSF leak could be confirmed intraoperatively in all 19 patients. In 4 (19%) of the 21 patients, DSM also showed a CSF-venous fistula at the same location as the postoperative dural tear. CONCLUSION: In this study, DSM had a 90% detection rate of visualizing the exact site of the dural breach in patients with extensive postoperative spinal CSF leaks. The coexistence of a CSF-venous fistula in addition to the primary dural tear was present in about one-fifth of patients. The presence of a CSF-venous fistula should be considered if CSF leak symptoms persist in spite of successful repair of a durotomy.

Transvenous Embolization for Cerebrospinal Fluid-Venous Fistula. A Case Series from a Single Community-Academic Center.

BACKGROUND: Transvenous embolization is a new treatment for spinal cerebrospinal fluid (CSF)-venous fistula, with only 1 reported large case series from the center that invented this technique. METHODS: We report the clinical and radiographic data of 5 consecutive patients who were diagnosed with CSF-venous fistula at a single community-academic medical center and were treated with transvenous embolization. All patients provided consent for this report. Institutional review board approval was not required because of the retrospective nature of this study describing standards of care. RESULTS: Five patients, 3 men and 2 women, with a median age of 57 years, were diagnosed between March and December 2021with spontaneous intracranial hypotension (SIH) as a result of CSF-venous fistula. Two patients were originally referred for middle meningeal artery embolization for chronic subdural hematoma. All fistulae were in the thoracic spine at a single level in 3 patients, 2 levels in 1 patient, and multiple levels in 1 patient. Transvenous embolization was technically successful in all cases, with no significant complications. Four patients (80%) had complete or near-complete resolution of clinical symptoms and returned to baseline function and employment status. One patient (20%) has had a remitting relapsing course. Posttreatment brain magnetic resonance imaging showed resolution of spontaneous intracranial hypotension findings in 4 patients (80%) and minimal changes in 1 patient (20%), who had significant clinical improvement. CONCLUSIONS: Transvenous embolization for the treatment of CSF-venous fistula is feasible and seems effective in the short-term. The results reported by the previous case series can be reproduced in other centers with available expertise and adherence to published diagnostic and treatment protocols.

[Spinal CSF-venous fistula: case report and literature review]. / Spinal'naya likvoro-venoznaya fistula kak prichina sindroma spontannoi vnutricherepnoi gipotenzii: sluchai iz praktiki i obzor literatury.

Syndrome of spontaneous intracranial hypotension is increasingly described in the literature as a multifactorial disease with impairment of the quality of life and risk of mortality. CSF-venous fistula as a cause of intracranial hypotension syndrome is extremely rare and requires complex diagnosis and timely surgical treatment. OBJECTIVE: We present a 55-year-old patient with acute spontaneous intracranial hypotension and spinal CSF-venous fistula. Literature data are also analyzed. RESULTS: Algorithm for diagnosis and efficacy of microsurgical resection of CSF-venous fistula is demonstrated. CONCLUSION: Intracranial hypotension following spinal fistula requires careful examination. Accurate understanding of pathophysiological and anatomical features of this disease is necessary to select an effective treatment method.

Ventral Intrameningeal Cyst Treatment and Management: Technical Note.

BACKGROUND: Intrameningeal cysts are rare lesions without definitive etiologies that can involve the dura or arachnoid mater. Spinal arachnoid cysts have been described, and several different etiologies have been hypothesized. This includes one-way valve mechanisms, traumatic herniation of arachnoid through the dura, and abnormal arachnoid membrane proliferation. To the authors' knowledge, no such descriptions exist regarding purely dural-based cystic lesions; however, the authors hypothesize similar mechanisms may be involved. Most notably, a traumatic injury to the dura leading to a one-way valve mechanism may allow for egress of cerebrospinal fluid between the dural layers, splitting them open. This progressive enlargement can lead to displacement of neural elements and subsequent neurological compromise. METHODS: We describe a 17-year-old girl who presented with progressive neck and back pain, left upper-extremity numbness, bilateral lower-extremity weakness, paresthesias, and numbness without obvious etiology despite an extensive neurologic investigation. She had undergone conservative management options including multiple medications, physical and chiropractic therapy, and epidural steroid injections. Computed tomography myelography revealed a cerebrospinal fluid leak into the lumbar epidural space for which surgical exploration was performed. Despite utilizing fluoroscopy and intrathecal fluorescein, no leak source was identified. Fluid collection was found contained within the dural layers rather than the epidural space. RESULTS: An intracystic blood patch was performed with near-complete resolution of the lesion by 6-week follow-up and near-complete return of neurologic function. CONCLUSIONS: Ventral panspinal cysts are an exceedingly rare cause of radiculopathy and myelopathy that can be resolved by an intracystic blood patch.

Targeted epidural blood patch through a catheter in the treatment of spontaneous intracranial hypotension.

OBJECTIVE: Spontaneous intracranial hypotension (SIH) can be effectively treated by epidural blood patch (EBP) following the primary unsuccessful conservative therapy. Nevertheless, multi-site cerebrospinal fluid (CSF) leaks or those originating at the cervical or thoracic spine remain therapeutically challenging. Therefore, this study aimed to present our experience in the treatment of thoracic CSF leaks using epidural catheters for the EBP infusion. METHODS: Three patients presenting with typical orthostatic headaches were qualified for an EBP procedure. Preoperative MRI scans, myelography, and CT myelography were performed. Additionally, delayed CT myelography was repeated after 3 h to identify the CSF leakage site. Patients were followed-up clinically and radiologically for three months. RESULTS: The CT myelography identified CSF leak at the T2-3 (case 1), T5-12 (case 2), and T3-7 level (Case 3). A 0.06" diameter lumbar drainage catheter (Case 1 and 2) or Abbot's spinal cord stimulation (SCS) catheter (Case 3) was inserted epidurally through the lower thoracic/lumbar single-entry point and advanced into the identified thoracic leak site. The average volume of injected blood was 15.7 ml. No procedure-related complications were observed, and all patients improved clinically. CONCLUSIONS: Epidural catheters remain safe and effective in treating thoracic and multi-site CSF leaks. In addition, Abbot's SCS catheter was found superior to the lumbar drainage catheter due to higher rigidity and bigger diameter despite being shorter than the lumbar drainage catheter.

Brain Sagging Dementia-Diagnosis, Treatment, and Outcome: A Review.

Brain sagging dementia (BSD), caused by spontaneous intracranial hypotension (SIH), is a rare syndrome that is only recently recognized, mimicking the clinical findings of behavioral variant frontotemporal dementia (bvFTD). Being aware of its signs and symptoms is essential for early diagnosis and treatment in this potentially reversible form of dementia. Our objective was to identify cases of BSD in the literature and present its clinical characteristics, diagnostic workup, treatment options, and outcome. The review was reported according to PRISMA guidelines and registered with the PROSPERO database (CRD42020150709). MEDLINE, EMBASE, PsychINFO, and Cochrane Library were searched. There was no date restriction. The search was updated in April 2021. A total of 983 articles were screened and assessed for eligibility. Twenty-nine articles (25 case reports and 4 series) and 70 patients were selected for inclusion. No cranial leak cases were identified. BSD diagnosis should be made based on clinical signs and symptoms and radiologic findings. There is a male predominance (F:M ratio 1:4) and a peak incidence in the 6th decade of life. The main clinical manifestation is insidious onset, gradually progressive cognitive and behavioral changes characteristic for bvFTD. Headache is present in the majority of patients (89%). The presence of brain sagging and absence of frontotemporal atrophy is an absolute criterion for the diagnosis. CSF leak is identified with myelography and digital subtraction myelography. The treatment and repair depend on the etiology and extent of the dural defect, although an epidural blood patch is the first-line treatment in most cases. With treatment, 81% experienced partial and 67% complete resolution of their symptoms. This review highlights the most important clinical aspects of BSD. Due to the sparse evidence and lack of BSD awareness, many patients are likely left undiagnosed. Recognizing this condition is essential to provide early treatment to reverse the cognitive and behavioral changes that may otherwise progress and fully impair the patient. Moreover, patients with longstanding SIH must be assessed carefully for cognitive and behavioral changes.

Algorithmic Multimodality Approach to Diagnosis and Treatment of Spinal CSF Leak and Venous Fistula in Patients With Spontaneous Intracranial Hypotension.

Spontaneous intracranial hypotension (SIH) is a disorder of CSF dynamics that causes a complex clinical syndrome and severe disability. SIH is challenging to diagnose because of the variability of its presenting clinical symptoms, the potential for subtle imaging findings to be easily overlooked, and the need for specialized diagnostic testing. Once SIH is suggested by clinical history and/or supported by initial neuroim-aging, many patients may undergo initial nontargeted epidural blood patching with variable and indefinite benefit. However, data suggest that precise localization of the CSF leak or CSF-venous fistula (CVF) can lead to more effective and durable treatment strategies. Leak localization can be achieved using a variety of advanced diagnostic imaging techniques, although these may not be widely performed at nontertiary medical centers, leaving many patients with the potential for inadequate workup or treatment. This review describes imaging techniques including dynamic fluoroscopic and CT myelography as well as delayed MR myelography and treatment options including percutaneous, endovascular, and surgical approaches for SIH. These are summarized by an algorithmic framework for radiologists to approach the workup and treatment of patients with suspected SIH. The importance of a multidisciplinary approach is emphasized.

Clinical and imaging outcomes of cerebrospinal fluid-venous fistula embolization.

BACKGROUND: We report outcomes of spontaneous intracranial hypotension (SIH) patients who underwent transvenous embolization of cerebrospinal fluid-venous fistulas (CSFVFs) confirmed on digital subtraction myelography (DSM) performed at our institution. METHODS: This is a retrospective evaluation of a prospectively collected database of SIH patients who underwent transvenous embolization of CSFVFs. Only patients who had fistulas confirmed on DSM performed at our institution were included. All patients had a baseline MRI and an MRI performed at least 90 days post-embolization, as well as clinical evaluation using the six item Headache Impact Test (HIT-6) and the Patient Global Impression of Change (PGIC) scales. Paired t-test was used to report changes in Bern MRI scores and HIT-6 scores at follow-up. RESULTS: 40 patients were included (29 female, 11 male). Mean age was 57.4±10.3 years. Mean Bern score improved from 5.7±3.0 at baseline to 1.3±2.0 at follow-up (p<0.0001). Mean HIT-6 score at baseline was 67.2±11.1 and at follow-up was 41.5±10.1 (p<0.0001). Median PGIC was 1, with 36 patients (90.0%) reporting at least minimal improvement and 32 patients (82.5%) reporting much or very much improvement. Complications included persistent local site pain in 12 patients (30%), suspected rebound intracranial hypertension requiring medical intervention in 7 patients (17.5%), and asymptomatic tiny Onyx emboli to the lungs in 3 patients (7.5%). CONCLUSIONS: Transvenous embolization of CSFVFs using Onyx is safe and effective, resulting in significant improvement in headache and overall clinical outcomes in nearly 90% of patients, and substantial improvements in brain MRI abnormalities.

Transvenous embolization of a cerebrospinal fluid-venous fistula for the treatment of spontaneous intracranial hypotension.

Cerebrospinal fluid-venous fistula is an increasingly recognized cause of spontaneous intracranial hypotension.1 The site of the leak is between the dural sleeve around a spinal nerve root and the surrounding foraminal veins. In appropriately investigated patients, transvenous embolization of the draining foraminal and paraspinal veins has been shown to be an effective way of treating the disease, with low periprocedural morbidity, improvement in symptoms and radiological appearances.2 Video 1 shows the technique employed in a typical case using Onyx (Medtronic, Minnesota, USA) to embolize a CSF-venous fistula at the right T10 neural foramen. neurintsurg;14/9/948/V1F1V1Video 1Video showing the technique for trans-venous embolization of a right T10 CSF-venous fistula for the treatment of spontaneous intracranial hypotension. The first section covers patient selection and work up, before then focusing on the technical aspects of navigating through the azygos system to the target foramen and completely occluding the pathway for CSF outflow.

The Impact of Anterior Spondylolisthesis and Kyphotic Alignment on Dynamic Changes in Spinal Cord Compression and Neurological Status in Cervical Spondylotic Myelopathy: A Radiological Analysis Involving Kinematic CT Myelography and Multimodal Spinal Cord Evoked Potentials.

STUDY DESIGN: A retrospective study of prospectively collected data. OBJECTIVE: This study aimed to examine how radiological parameters affect dynamic changes in the cross-sectional area of the spinal cord (CSA) in cervical spondylotic myelopathy (CSM) patients and how they correlate with the severity of myelopathy, by evaluating multi-modal spinal cord evoked potentials (SCEPs). SUMMARY OF BACKGROUND DATA: Appropriate assessments of dynamic factors should reveal hidden spinal cord compression and provide useful information for choosing surgical procedures. METHODS: Seventy-nine CSM patients were enrolled. They were examined with kinematic CT myelography (CTM), and the spinal levels responsible for their CSM were determined via SCEP examinations. The C2-7 angle, C2-7 range of motion, and percentage of slip were measured on the midsagittal view during flexion and extension, and the CSA was measured on the axial view in each neck position using kinematic CTM. The patients who exhibited the smallest CSA values during extension and flexion were classified into Groups E and F, respectively. RESULTS: Fifty-two (65.8%) and 27 (34.2%) cases were included in Groups E and F, respectively. The preoperative JOA score did not differ significantly between the groups; however, the preoperative lower-limb JOA score of Group F was significantly lower than that of Group E (2.24 ±â€Š0.82 vs. 2.83 ±â€Š1.09, P = 0.016). In the multiple logistic regression analysis, a small C2-7 angle during extension (ß = 5°, odds ratio: 0.69, 95% confidence interval [CI]: 0.54-0.90) and the slip percentage during flexion (ß = 5%, odds ratio: 1.42, 95% CI: 1.09-1.85) were identified as significant predictors of belonging to Group F. CONCLUSION: Exhibiting more severe spinal cord compression during neck flexion was associated with a small C2-7 angle and anterior spondylolisthesis. The neurological status of the patients in Group F was characterized by severe lower limb dysfunction because of a disturbed blood supply to the anterior column.Level of Evidence: 4.

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)

Intrathecal iodinated contrast-induced transient spinal shock.

Transient spinal shock is a previously unreported complication of intrathecal contrast. A 63-year-old man presented with the chief complaint of worsening back pain. Computed topography of lumbar spine without contrast showed a lytic lesion. After international normalized ratio (INR) correction, patient was sent for CT myelogram. After intrathecal contrast injection, the patient dropped his blood pressure profoundly and developed clinical manifestations of spinal shock. Emergent intravenous bolus fluids were initiated resulting in improvement in blood pressure. Patient's spinal shock resolved within hours. CT myelogram was normal except previously known lytic lesion. It was concluded that the transient shock was most likely due to contrast injection. We believe that this is the first reported case of transient spinal shock following CT myelogram using water-soluble iodinated non-ionic contrast agent administered intrathecally.

Computed tomographic features of gastric and esophageal content in dogs undergoing CT myelography and factors influencing the presence of esophageal fluid.

BACKGROUND: Gastroesophageal reflux (GER) has been reported to be a common finding in dogs under general anesthesia. OBJECTIVES: The aim of this retrospective study was to assess the esophageal and gastric contents in a population of dogs undergoing computed tomographic myelography (myelo-CT) examination and to evaluate the factors influencing the presence of esophageal fluid (gastric content, duration of anesthesia, body position, and intrinsic factors). METHODS: Esophageal and gastric contents of 83 non-brachycephalic dogs were retrospectively assessed based on plain and myelo-CT scans. Age, weight, breed, sex, and the time between the 2 computed tomography [CT] scans were included. RESULTS: Esophageal fluid was present in 19% (16/83) of the animals, and 14% (12/83) and 46% (37/83), respectively, had fluid or food material in their stomachs. The frequency of observing esophageal fluid on myelo-CT scans was significantly increased compared with plain CT scans (p = 0.006). The presence of gastric fluid was significantly associated with an increased frequency of observing esophageal fluid compared to other gastric contents (p = 0.049; odds ratio, 3.1). The presence of esophageal fluid was not correlated with alimentary gastric contents (p = 0.17). Increased body weight and duration of anesthesia were significantly associated with an increased frequency of observing esophageal fluid (p = 0.022, p = 0.021). CONCLUSIONS: Unlike alimentary gastric contents, fluid gastric contents were correlated with the presence of esophageal fluid upon myelo-CT. The observation of fluid in the esophagus may be consistent with GER. This study provides data additional to pH monitoring studies of GER and may support previous studies recommending shorter pre-anesthetic fasting periods in dogs.

Fatality From Status Epilepticus After Myelography.

OBJECTIVE. Myelography is a commonly used procedure to evaluate the spinal canal. However, the procedure is not without risk, chiefly risk of seizure after intrathecal administration of iodinated contrast material. CONCLUSION. The risk of seizure remains an important concern for radiologists, who should strongly consider practice parameter guidelines that address this risk.

Permanent Paraplegia as a Complication of Injection of Contrast Media at L2-L3 Vertebral Level.

BACKGROUND: The lumbar intrathecal (subarachnoid) space is accessed for both therapeutic and diagnostic purposes. Occasionally, the needle may unintentionally enter the intrathecal space during lumbar interlaminar epidural steroid injections (LESIs)-one of the most commonly performed medical procedures in the United States. Ordinarily, this merely constitutes a minor complication or even a desired placement (in the case of some diagnostic procedures). However, some patients have a rare condition wherein the spinal cord terminates below the L2 vertebral level (tethered cord). In such cases, injections administered at the lumbar level may potentially result in spinal cord damage and irreversible paraplegia if the physician performing the intervention does not recognize the intramedullary position of the needle. OBJECTIVE: The aim of this study is to describe and analyze an unintentional L2-L3 injection of contrast medium into a tethered spinal cord. Many physicians may consider lumbar injections "safe" because the spinal cord usually terminates at or above the L2 vertebral level. However, complacency stemming from this false impression of safety contributes to nonadherence to practice guidelines, which may lead to catastrophic neurological complications. Presented here is the first published occurrence of paraplegia that resulted from contrast medium injection into the spinal cord during a myelography study performed below the L2 vertebral level. CONCLUSIONS: Disregard of the procedural guidelines by the physicians performing an elective diagnostic intervention may cause devastating neurological complications. The described casualty occurred because of failure to review previous imaging studies, injection of the contrast medium despite unsuccessful attempts to aspirate cerebrospinal fluid, and an unwillingness to terminate the procedure immediately when the patient reported an unusual sensation in both of his lower extremities. Consequently, we suggest that not only for cervical and thoracic but also for lumbar interlaminar ESIs, previous imaging studies should be reviewed before the injection.

Obstruction of Ventriculoperitoneal Shunt After Myelography-Report of a Unique Case and Its Treatment.

BACKGROUND: Myelography, frequently supplanted by noninvasive, efficient magnetic resonance imaging, remains a useful technique when evaluating the spinal canal in nerve root avulsion, radiation therapy treatment planning, cerebrospinal fluid (CSF) loculation, and CSF leak. Myelography is achieved through a lumbar puncture and instillation of nonionic, water-soluble intrathecal iohexol (Omnipaque, GE Healthcare, Marlborough, Massachusetts, USA) contrast. The aim of the study was to highlight a possible complication of obstruction of a shunt valve due to an increased viscosity of the CSF after intrathecal Omnipaque contrast administration during myelography. CASE DESCRIPTION: The authors report a case of myelography that resulted in obstruction of a ventriculoperitoneal (VP) shunt. A 23-year-old female with significant medical history of neurofibromatosis type I, obstructive hydrocephalus, anterior cervical diskectomy and fusion, and VP shunt placement underwent diagnostic computed tomography after myelography with Omnipaque contrast to assess possible CSF loculation and cord impingement from her cervical instrumentation. The patient experienced somnolence after myelography from obstruction of the VP shunt, with marked ventriculomegaly demonstrated by computed tomography of the head. A shunt tap and shunt pumping regimen resulted in resolution of the obstruction and hydrocephalus, with return to neurologic baseline. CONCLUSIONS: This is a recent case of VP shunt obstruction after myelography, of which previous cases reported are decades old. A shunt pumping regimen may be a nonoperative, effective mean for similar mechanical obstructions of VP shunts for restoration of flow and patency of the shunt system in these patients. We encourage physicians to consider the possibility of shunt obstruction after diagnostic myelography. Caution and close observation should be considered in patients undergoing myelography with a programmable VP shunt.