Abstract
Dear Sir I have read with interest the article of M Kueper et al. on ‘Cerebral venous thrombosis after epidural blood patch: coincidence or causal relation? A case report and review of the literature’ (1).
In this article the authors report a case of cortical cerebral venous thrombosis after epidural blood patch was performed for treatment of post-dural puncture headache after epidural analgesia for delivery.
We have observed a 52-year-old woman treated with two epidural injections of a local anaesthetic and steroid because of low back from lumbar stenosis who, after the second injection, started complaining about severe, gravative, occipital headache and nausea. The headache was alleviated when lying down and exacerbated when resuming an upright position. Seven days after the headache onset she exhibited a moderate left hemiparesis and, after 24 h, she had an episode of tonic-clonic seizures. For this reason she was admitted to our hospital. The left hemiparesis recovered progressively after 48 h. Later on, the patient had three mild partial sensitive seizures on her left side (tingling and numbness) and was treated with carbamazepine 800 mg/day with complete control of symptoms. Electroencephalography (EEG) showed epileptiform discharge on right temporal side. Brain computed tomography showed a small right fronto-parietal cortical haemorrhage. Brain magnetic resonance imaging (MRI) with gadolinium contrast showed a small right fronto-parietal cortical haemorrhage with focal oedema and diffuse pachymeningeal enhancement. Brain MRI venography was normal. Cerebral angiography showed no flow signal in a few frontal and parietal cortical veins corresponding to the haemorrhage, a finding suggestive of cortical cerebral venous thrombosis. Laboratory investigation for thrombophilia was unrevealing. A diagnosis of intracranial hypotension, after accidental dural puncture during an epidural injection of steroid, was made. Fifteen days after the headache onset, the patient was treated with an autologous epidural blood patch (EBP) (20 mL). The headache disappeared within a few minutes after the procedure. After 4 months' follow-up the patient was in good health. At that time, her brain MRI was normal, as well as her cerebral angiography, which showed restoration of flow signal in the right fronto-parietal cortical veins. Our case, in whom cortical cerebral venous thrombosis preceded EBP, and another reported in the literature (2), demonstrate that EBP is an effective procedure to treat cortical cerebral venous thrombosis from intracranial hypotension. I think that in the case described by Kueper et al., in whom, conversely, EBP preceded cortical cerebral venous thrombosis, this condition was caused by the several risk factors for cerebral venous thrombosis (puerperal state, heterozygous factor V Leiden and stasis of blood flow via venodilation) presented in the patient, but not by EBP.
As long as such a temporal relationship is not documented in at least one subject without any other risk factor for cerebral venous thrombosis, a pathophysiological link between EBP and cerebral venous thrombosis remains hard to establish.