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The clue is in the kidneys: greater renal contrast medium accumulation on ipsilateral side down CT myelogram after lateral decubitus digital subtraction myelogram as a predictor of laterality of cerebrospinal fluid leak

Spontaneous spinal CSF leaks typically cause orthostatic headache, but their detection may require specialized and invasive spinal imaging. We undertook a study to determine the value of simple optic nerve sheath MR imaging measurements in predicting the likelihood of finding a CSF-venous fistula, a type of leak that cannot be detected with routine spine MR imaging or CT myelography, among patients with orthostatic headache and normal conventional brain and spine imaging findings. This cohort study included a consecutive group of patients with orthostatic headache and normal conventional brain and spine imaging findings who underwent digital subtraction myelography under general anesthesia to look for spinal CSF-venous fistulas. The study group consisted of 93 patients (71 women and 22 men; mean age, 47.5 years; range, 17-84 years). Digital subtraction myelography demonstrated a CSF-venous fistula in 15 patients. The mean age of these 8 women and 7 men was 56 years (range, 23-83 years). The mean optic nerve sheath diameter was 4.0 mm, and the mean perioptic subarachnoid space was 0.5 mm in patients with a CSF-venous fistula compared with 4.9 and 1.2 mm, respectively, in patients without a fistula (P < .001). Optimal cutoff values were found at 4.4 mm for optic nerve sheath diameter and 1.0 mm for the perioptic subarachnoid space. Fistulas were detected in about 50% of patients with optic nerve sheath diameter or perioptic subarachnoid space measurements below these cutoff values compared with <2% of patients with optic nerve sheath diameter or perioptic subarachnoid space measurements above these cutoff values. Following surgical ligation of the fistula, optic nerve sheath diameter increased from 4.0 to 5.3 mm and the perioptic subarachnoid space increased from 0.5 to 1.2 mm (P < .001). Concerns about a spinal CSF leak should not be dismissed in patients with orthostatic headache when conventional imaging findings are normal, and simple optic nerve sheath MR imaging measurements can help decide if more imaging needs to be performed in this patient population.

BACKGROUNDCSF leaks can cause resistant subdural hematomas (SDHs). Spinal CSF-venous fistulas (CVFs) are a rare cause of this problem. A better understanding of this phenomenon would guide decision-making when planning treatment and follow-up. The authors reviewed a case of a recurrent right-sided SDH secondary to a previously unknown CVF. In addition, a systematic review was conducted in accordance with PRISMA guidelines for previously documented cases.OBSERVATIONSSeven cases were found in the literature, with ours representing the eighth case of recurrent SDH due to a CVF-induced CSF leak. The mean age was 60 years, and 75% of patients were male. Common initial presentations included headache (100%), tinnitus (75%), and nausea/vomiting (50%). All patients were treated with Onyx embolization, with 62.5% also receiving middle meningeal artery (MMA) embolization. All patients experienced improvement of SDH size after treatment, with 62.5% demonstrating complete resolution.LESSONSSpinal CVFs are a rare but serious cause of CSF leaks and recurrent SDHs. Cases typically occur in men around 60 years of age, and common symptoms include headache, tinnitus, and nausea/vomiting. Treatment with CVF embolization results in improvement or resolution of SDH burden, while the role of MMA embolization in the treatment of these SDHs remains unclear.https://thejns.org/doi/10.3171/CASE25338

Percutaneous Treatment and Post-treatment Management of CSF Leaks and CSF-Venous Fistulas in Spontaneous Intracranial Hypotension.

OBJECTIVE Post-dural puncture headaches are common, and the treatment of such headaches can be complex when they become chronic. Among patients with spontaneous spinal CSF leaks, digital subtraction myelography (DSM) can localize the exact site of the leak when an extradural CSF collection is present, and it can also demonstrate CSF-venous fistulas in those without an extradural CSF collection. The authors now report on the use of DSM in the management of patients with chronic post-dural puncture headaches. METHODS The patient population consisted of a consecutive group of 27 patients with recalcitrant post-dural puncture headache that had lasted from 2 to 150 months (mean 26 months). RESULTS The mean age of the 17 women and 10 men was 39.1 years (range 18-77 years). An extensive extradural CSF collection was present in 5 of the 27 patients, and DSM was able to localize the exact site of the dural defect in all 5 patients. Among the 22 patients who did not have an extradural CSF collection, DSM showed a CSF-venous fistula in 1 patient (5%). Three other patients had a small pseudomeningocele at the level of the dural puncture. Percutaneous glue injection or microsurgical repair resulted in resolution of symptoms in 8 of the 9 patients in whom an abnormality had been identified on imaging. CONCLUSIONS Digital subtraction myelography is able to precisely localize the dural puncture site in patients with a post-dural puncture headache and an extensive extradural CSF collection, and it may rarely detect a CSF-venous fistula in such patients without an extradural CSF collection.

BackgroundThe majority of patients with spontaneous intracranial hypotension (SIH) are symptomatic. Some patients are discovered incidentally. The proportion of asymptomatic SIH has never been defined. This article reports our institution’s...

This chapter evaluates spontaneous intracranial hypotension (SIH), which is a well-recognized syndrome that is characterized by orthostatic headaches in association with a variety of other symptoms. It results from an occult leakage of cerebrospinal fluid (CSF) through weakness of the dura from nerve root sleeves, dural rents caused by herniated discs or osteophytic microspurs, or by CSF-venous fistulas. In the majority of cases, the cause of SIH is unclear, but possible precipitants include a history of trivial trauma and weakness of the dural sac. The characteristic clinical feature of SIH is headache, which is usually throbbing, bilateral, and worsened by Valsalva maneuvers. The diagnosis of SIH may be established in several ways, but there is not a single modality that consistently reveals the answer. Treatment of SIH includes conservative measures such as bed rest and hydration and caffeine administration (by mouth or intravenously). Epidural blood patching may provide relief.

(N Engl J Med. 2021;385:2173–2178) Spontaneous intracranial hypotension presents as below-normal cerebrospinal fluid (CSF) due to CSF leakage from an unknown cause. While spontaneous intracranial hypotension is treatable, it is difficult to diagnose. Imaging has identified 3 types of spontaneous spinal CSF leaks: linear tear in the dura posterolateral or ventral to the spinal cord; diffuse dilatations of the dural sac or leakage at the simple meningeal diverticula; or the space between the CSF-venous fistulas and proximal veins. It is estimated that spontaneous intracranial hypotension occurs in 4 to 5 cases per 100,000 population.

Cerebrospinal fluid (CSF) leak is a well-known complication of skull or sinus surgery. Radionuclide cisternography has high sensitivity for detection of CSF leak, commonly performed in conjunction with radioactivity assay of nasal pledgets. Our objective was to highlight the usefulness of single photon emission tomography/computed tomography (SPET/CT) in radionuclide cisternography by presenting a case of a 41 years old man with right sided rhinorrhea following craniotomies and sinus surgery, who was subjected to radioactivity assay of nasal pledgets and radionuclide cisternography for suspected CSF leak. Although no CSF leak was detected by radioactivity assay of pledgets placed in the nasal cavity, asymmetric radiotracer activity was noted on cisternographic images in the left temporal region, which was found to correspond to an enlarged CSF space in the left middle cranial fossa, not CSF leak, on SPET/CT images. SPET/CT was useful in the differentiation of asymmetric CSF radiotracer activity caused by a normal variant or post surgical changes of anatomic structures from abnormal radiotracer activity secondary to CSF leakage on radionuclide cisternography.

Background: Endoscopic repair of cerebrospinal fluid (CSF) leaks has been well described in the literature as an effective method for the treatment of sinonasal skull base defects. However, despite the ongoing evolution of the endoscopic techniques for repair, site localization is a diagnostic challenge. The limitations and morbidity associated with diagnostic imaging studies such as high-resolution computer tomography (HRCT), magnetic resonance imaging (MRI), and computed tomography (CT) cisternography in detecting CSF leaks has created a need for more accurate and less invasive radiographic imaging modalities. In our study, we evaluate a novel technique of fusing HRCT and MRI imaging for the detection of CSF leaks, as well as its ability to aid in intraoperative localization of skull base defects through computer-assisted image guidance.

BACKGROUND AND OBJECTIVES:Spinal cerebrospinal fluid (CSF) leaks may cause a myriad of clinical symptoms, the most common being orthostatic headache. Lateral leaks (Type II) and direct CSF-venous fistulas (Type III) are a subgroup of spinal CSF leaks, representing about 1/3 of spinal CSF leaks. This study aimed to analyze the risk and efficacy of nerve root clipping in patients with Type II and Type III CSF leaks.METHODS:All consecutive patients with Type II and Type III CSF fistulas treated with nerve root clipping at our institution from May 2018 to December 2022 were included. Patients were evaluated for postoperative sensory motor deficits and neuropathic pain using the “Douleur Neuropathique 4” questionnaire, and the outcome was evaluated using the “Patient Global Impression of Change” and the return-to-work rate.RESULTS:A total of 40 patients were included, and the mean follow-up time was 22 months. According to the Patient Global Impression of Change, significant symptoms improvement was reported in 85% of patients. Over 87% of patients returned to work fully or partially. One patient experienced a low-grade motor deficit after T1-nerve root clipping. 2.5% of patients developed postoperative neuropathic pain requiring medical treatment under which they fully improved. Over 80% of patients developed dermatomal hypoesthesia, with no reported effect on quality of life.CONCLUSION:The surgical strategy of noneloquent nerve root clipping shows favorable outcomes and return-to-work rates. There are instances of neuropathic pain and dermatomal hypoesthesia with no significant morbidity. Despite the favorable outcome and low recurrence rate, nerve root-sparing surgical techniques should be further explored.

Spontaneous intracranial hypotension is an increasingly recognized syndrome caused by a spinal CSF leak, with most reported cases occurring in adults. The use of specialized or advanced myelography to localize spinal CSF leaks has evolved substantially in recent years, particularly since the initial description of CSF-venous fistulas in 2014. To our knowledge, no prior series have evaluated the use of specialized myelographic techniques to localize CSF leaks in children with spontaneous intracranial hypotension, likely because the disease is rare in this patient population. This issue may be compounded by a hesitation to perform invasive procedures in children. In this clinical report, we conducted a multi-institutional review of pediatric patients with spontaneous spinal CSF leaks localized using advanced myelographic techniques, such as prone and decubitus digital subtraction and CT myelography, as well as dynamic CT myelography. We report the clinical features of these patients, as well as imaging findings, types of leaks discovered, and method of treatment. We found that the primary types of spontaneous spinal CSF leaks that occur in adults, including dural tears and CSF fistulas, can be seen in children, too. Furthermore, we show that specialized myelographic techniques can successfully localize these leaks and facilitate effective targeted treatment.

A 19-year-old woman was hospitalized for a head injury resulting from an automobile accident. The radiographic computed tomographic (CT) scan showed a skull fracture, and magnetic resonance imaging (MRI) revealed a soft tissue signal intensity mass in her right temporal region, suggesting the possibility of cerebrospinal fluid (CSF) leak. For this reason, In-111 cisternography was performed to clarify the presence of the CSF leak. In addition, dual-isotope SPECT with In-111 DTPA and Tc-99m HMDP was performed. These images clearly located a CSF leak at the patient's right mastoid. Dual-isotope SPECT with In-111 DTPA and Tc-99m HMDP was useful for detecting and locating the CSF leak.

Tc 99m macroaggregated albumin cisternography for the detection of persistent cerebrospinal fluid (CSF) leak in an animal model

A CSF leak can be difficult to locate in patients who present with spontaneous intracranial hypotension (SIH). The purpose of this case series was to describe the authors' experience with intrathecal preservative-free normal saline challenge coupled with contrast-enhanced MR myelography (CEMRM), which was used to provoke and detect a CSF leakage site in patients with SIH. The authors performed a retrospective review of the records of patients who underwent preservative-free normal saline challenge followed by intrathecal gadolinium (Gd) contrast infusion and MR myelography from 2010 to 2012. The records survey identified 5 patients who underwent 6 procedures. Intrathecal preservative-free normal saline challenge followed by CEMRM identified a CSF leak during 5 of the 6 procedures. Previous CT myelograms were available from 4 patients, which did not reveal a leakage site. A CT myelogram of 1 patient showed a single leak, but the authors' saline challenge-CEMRM technique identified multiple additional leakage sites. Three patients exhibited transient postprocedural symptoms related to the saline infusion, but no long-term or permanent adverse effects related to the procedure were observed. Instillation of preservative-free normal saline into the thecal sac followed by intrathecal Gd infusion is a safe technique that may increase the detection of a CSF leak on MR myelography images in patients with SIH.