Papilledema in a Patient With Intracranial Hypotension

We describe a young woman who developed intracranial hypotension with large subdural hematomas after epidural analgesia used during labor and delivery. She was then found to have bilateral optic nerve head swelling presumed to be due to papilledema. We described possible mechanisms for the development of papilledema in this clinical context.

Clinical Correspondence Section Editors: Robert Avery, DO Karl C. Golnik, MD Caroline Froment, MD, PhD An-Guor Wang, MD Papilledema in a Patient With Intracranial Hypotension Jason M. Kwok, MD, Daniel M. Mandell, MD, PhD, Edward A. Margolin, MD W e describe a young woman who developed intracranial hypotension with large subdural hematomas after epidural analgesia used during labor and delivery. She was then found to have bilateral optic nerve head swelling presumed to be due to papilledema. We described possible mechanisms for the development of papilledema in this clinical context. A 36 year-old previously healthy woman underwent emergency Cesarean section for fetal heart rate decelerations. Epidural anesthesia was used for pain control during the labor and subsequent Cesarean section. Since the delivery, the patient experienced constant, severe, pounding occipital headaches that worsened with standing up. She saw her obstetrician and given her recent history of epidural anesthesia, and the postural nature of the headache was diagnosed with a cerebral spinal fluid (CSF) leak and referred to anesthesia for an epidural blood patch (EBP) placement. This was performed with partial improvement of headaches and complete resolution of its postural component. Around the same time patient noticed slightly blurry vision in each eye and saw her optometrist who observed bilateral optic nerve head edema and referred her for a neuro-ophthalmology evaluation. During the consultation, she still complained of headaches, although stated that they have improved after the epidural patch placement and admitted to experiencing intermittent pulsatile tinnitus. She denied transient visual obscurations and diplopia. She was overweight with body mass index of 32. She gained 20 lbs during pregnancy but already lost this weight after delivery. She did not use any medications or over-the-counter supplements other than acetaminophen as needed. Visual acuity was 20/20 in each eye. There was no relative afferent pupillary defect. There was bilateral optic disc edema with peripapillary hemorrhages on funduscopy (Fig. 1). Humphrey visual field testing demonstrated enlarged blind spots in each eye. Urgent MRI of the brain was performed and showed bilateral subacute subdural hematomas around the cerebral convexities. These were moderate in size on the left side and small on the right side (Fig. 2A–C). A computed tomography venogram showed no venous sinus thrombosis, but there was extrinsic narrowing of the transverse–sigmoid venous sinus junction bilaterally, an indirect sign of increased CSF pressure (Fig. 2D, E). There were no signs of intracranial hypotension such as dural sinus distension or dural enhancement. MRI of the spine was normal. There was no evidence of coagulopathy on hemostasis testing, and complete blood count was normal. Given the improvement in symptoms, the patient was discharged home with the diagnosis of subrual hematoma (SDH) secondary to CSF leak following epidural anesthesia. Two weeks later, the headaches improved significantly, and there was complete resolution in the optic disc edema when she was seen in follow-up 1 month later. SDH is a rare but serious complication of CSF leaks and intracranial hypotension (ICH). It has been reported in settings of primary spontaneous CSF leaks and secondarily in cases of neuraxial anesthesia and diagnostic lumbar puncture (1–3). The leakage of CSF is postulated to cause caudal shift of intracranial contents with resultant traction and tearing of the bridging veins. Clinical symptoms of SDH vary widely from mild headaches to seizures and decreased level of consciousness (2). In the postpartum setting, the development of SDH is primarily seen after neuraxial anesthesia, including spinal anesthesia or epidural anesthesia with inadvertent dural puncture (2,3). Diagnosis of SDH can be difficult in the obstetric population as postpartum headaches are common, and Departments of Ophthalmology and Vision Sciences (JMK, EAM), and Medical Imaging (DMM), University of Toronto, Toronto, Canada; and Division of Neurology (EAM), Department of Medicine, University of Toronto, Toronto, Canada. The authors report no conflicts of interest. All authors contributed equally to manuscript preparation, writing and approval of the final draft. Address correspondence to Edward A. Margolin, MD, Department of Ophthalmology and Vision Sciences, University of Toronto Faculty of Medicine, 801 Eglinton Avenue West Suite 301, Toronto, ON M5N 1E3, Canada; E-mail: [e-mail] e708 FIG. 1. Optic disc photographs of the right and left eye demonstrating moderate optic disc edema with blurred optic disc margins, hyperemia of the optic nerve, and peripapillary hemorrhages. Kwok et al: J Neuro-Ophthalmol 2021; 41: e708-e710 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited. Clinical Correspondence FIG. 2. Brain MRI and axial T2-weighted fluid-attenuated inversion recovery image images (A and B) show bilateral cerebral convexities subdural hematomas (arrows), moderate in size on the left side and small on the right side. Sagittal T1-weighted images (C) show hyperintensity in the hematoma consistent with subacute blood. Computed tomographic venogram, sagittal reformats through the right (D) and left (E) transverse venous sinuses show that the sinuses are very narrow and extrinsically compressed. although most are secondary to tension headaches, serious intracranial pathology such as dural venous thrombosis can rarely be the culprit (4). Our patient presented with unrelenting headache that improved after an EBP was performed 1 month later, confirming iatrogenic CSF leak as the most likely cause of postpartum headache. The most common neuro-ophthalmic consequence of ICH is sixth nerve palsy presumably due to its stretching in the subarachnoid portion, where it is anchored to the pons on one side and Dorello canal on the other, after the downward sinking of the brain (5). Nonspecific visual field defects have also been reported, possibly secondary to the chiasmal or optic tract by the distended third ventricle. Papilledema has not been reported as a direct consequence of ICH in the literature (5). We believe that in our patient, SDHs have developed as a result of continuous CSF leak. When the CSF circulating space has been closed after the placement of EBP, the volume occupied by large bilateral SDHs has caused increased ICP, which in turn resulted in papilledema. It is also possible that rebound intracranial hypertension ensued after the placement of EBP as during the period of CSF leak, CSF was produced in greater quantity and/or resorption of CSF was slower due to CSF volume depletion (6). This should have been a transient phenomenon, though, because the CSF dynamic has normalized after the ongoing CSF leak was sealed and papilledema was present 1 month after that, making this an unlikely explanation. Finally, there is a remote possibility that there was preexisting idiopathic intracranial hypertension (IIH) and the CSF leak after the epidural anesthesia has Kwok et al: J Neuro-Ophthalmol 2021; 41: e708-e710 caused lowering of the ICP with subsequent increase in ICP after the placement of the EBP. Spontaneous CSF leaks in patients with IIH with rebound papilledema after the repair of the leak have been well described (7). However, given that headaches started immediately after the epidural anesthesia and improved after the placement of EBP, this is unlikely. In summary, we present a unique case of patient who developed increased ICP as a direct result of ICH: rupture of the bridging veins in subdural space caused formation of large SDHs, which resulted in increased ICP and papilledema. Eventual resolution of papilledema as SDHs continued to decrease in size and CSF dynamics was restored confirms our hypothesis. STATEMENT OF AUTHORSHIP Category 1: a. Conception and design: E. A. Margolin, and J. M. Kwok; b. Acquisition of data: E. A. Margolin, and J. M. Kwok; c. Analysis and interpretation of data: E. A. Margolin, and J. M. Kwok. Category 2: a. Drafting the manuscript: E. A. Margolin, and J. M. Kwok; b. Revising it for intellectual content: E. A. Margolin, and J. M. Kwok. Category 3: a. Final approval of the completed manuscript: E. A. Margolin, and J. M. Kwok. REFERENCES 1. Schievink WI, Maya MM, Moser FG, Tourje J. Spectrum of subdural fluid collections in spontaneous intracranial hypotension. J Neurorg. 2005;103:608–613. 2. Cuypers V, Van de Velde M, Devroe S. Intracranial subdural haematoma following neuraxial anaesthesia in the obstetric population: a literature review with analysis of 56 reported cases. Int J Obstet Anesth. 2016;25:58–65. e709 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited. Clinical Correspondence 3. Lim G, Zorn JM, Dong YJ, DeRenzo JS, Waters JH. 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