The Rare Presentation of Traumatic Intracranial Hypotension: A Case Report

Abstract

Cerebrospinal fluid (CSF) provides buoyant support to the brain and spinal cord. According to the Monroe-Kellie doctrine, confined space in the cranium causes any change in CSF volume contributing to significant intracranial pressure changes, which cause a variety of pathologies and symptoms. We, hereby, present a case of a 33-year-old gentleman who after a motorcycle road traffic accident came to us complaining of persistent headache and neck pain with subdural hematoma (SDH) like presentation, clinically and radiologically, but was reevaluated and diagnosed as traumatic intracranial hypotension and successfully managed surgically after that. Hygromas are believed to be compensatory enlargement of the subdural space due to the loss of CSF volume. The true mechanism of the development of SDH or hygroma due to intracranial hypotension is yet to be hypothesized but provisionally described by a rupture of the bridging veins by being pulled away from the dura because of the low intracranial pressure (ICP) and brain descent. Many prior cases in the literature are shown to have treated the patient with immediate burr hole and decompression of SDH, but this paradoxically worsens the patient due to further lowering of ICP. The causes of prolonged postconcussion headaches are often unidentified, of which intracranial hypotension caused by a CSF leak is potentially under-recognized. In such cases, bilateral SDH with mass effect must be ruled out of any CSF leak before attempting the lifesaving decompressive surgery, as it may paradoxically lead to further morbidity and mortality of the patient.

Keywords

cerebral contusion - headache - hygroma - intracranial hypotension - SDH - traumatic IH

Introduction

Cerebrospinal fluid (CSF) provides buoyant support to the brain and the spinal cord. According to the Monroe–Kellie doctrine, confined space in the cranium causes any change in CSF volume contributing to significant intracranial pressure (ICP) changes, which cause a variety of pathologies and symptoms.[1] [2]

The symptoms of the patient in both conditions, that is, elevated or reduced ICP, are the same including postural headache, neck retraction symptoms, and bradycardia; the incidence of increased intracranial tension following brain surgeries is significantly higher compared with the occurrence of intracranial hypotension (IH).[3] However, once recognized, IH is relatively easier and faster to treat compared with intracranial hypertension with complete resolution.

We, hereby, present a case of motorcycle road traffic accident (RTA) with subdural hematoma (SDH) like presentation, clinically and radiologically but re-evaluated and diagnosed as traumatic IH and successfully surgically managed, thereafter.

Case Report

A 33-year-old gentleman presented to us with a history of persistent holocranial headache for the past 1 month along with neck pain. A history of falls from a motorcycle in an RTA was reported 1 month before the onset of symptoms. There was no loss of consciousness, seizures, or any significant symptoms during 72 to 96 hours of trauma, after which the above-mentioned complaints emerged. The headache was holocranial, mild to moderate in intensity, dull aching, continuous, not relieved with medication with the severity of pain gradually increasing, more in the occipital region, aggravated by sitting and standing, and improved by lying down and taking rest. It was not associated with any nausea, vomiting, or vision abnormalities. The patient also complained of simultaneous complaint of neck pain, which was continuous and nonradiating, with no aggravating factors, partly relieved with medication (for which an X-ray of the skull and cervical spine was done, which was normal).

Upon examination, the patient was drowsy and disoriented and did not respond to medications. His Glasgow Coma Scale (GCS) score was 08/15 and his vital signs were stable. His fundus was normal with no signs of papilledema. His bilateral pupils were normal in size and normally reactive to light. The extraocular movements in both eyes were full. No motor or sensory deficit was elicited. There were no signs of meningeal irritation.

Admission MRI of the brain and cervical spine was reported as bilateral SDH with mass effect ([Fig. 1]) showing tonsillar herniation approximately 9.2 mm below McRae's line and mild brainstem herniation. The patient was planned for burr hole and drainage. But upon re-reading the MRI films, along with bilateral extra-axial subdural collections, a droopy penis sign ([Fig. 2]; splenium of the corpus callosum sagging downward) was seen. Hence, a repeat cranial MRI was performed and diffuse pachymeningeal enhancement of the dura with engorged dural venous sinuses was noted ([Fig. 3]), along with previous findings. MRI of the cervical spine was screened again and a focal CSF collection between the posterior elements of C1 and C2 with a focal discontinuity in the cortical outline of lamina was seen, which suggested a dural tear ([Figs. 4] and [5]).

Fig. 1 Bilateral extra-axial subdural collections with mass effect.

Fig. 2 Droopy penis sign seen on T2-weighted sagittal MRI of the brain.

Fig. 3 Diffuse pachymeningeal enhancement of the dura with engorged dural venous sinuses in T2-weighted sagittal section of MRI of the brain.

Fig. 4 Focal cerebrospinal fluid (CSF) collection between the posterior elements of C1 and C2 with a focal discontinuity in the cortical outline of lamina suggestive of dural tear.

Fig. 5 T2 axial section at the C2 level showing dural tear.

So, the International Classification of Headache Disorders, 3rd edition (ICHD-3), was referred to and the diagnostic criteria for headache and MRI findings attributed the diagnosis to spontaneous IH. The patient was then kept on continuous intravenous (IV) fluids, oral theophylline, oral caffeine, and oral nonsteroidal anti-inflammatory drugs (NSAIDs). But the headache did not improve. Hence, surgical intervention was planned. Owing to the immediate unavailability of an epidural blood patch, laminectomy followed by duraplasty was done. Twenty-four hours after surgery, the patient's symptoms had significantly improved, even in the supine and standing posture. Hence, it was diagnosed as a case of traumatic IH.

Discussion

IH was described for the first time in 1953 as “hypotension of the cerebral fluid” by the German neurologist Georges Schaltenbrand.[4] The cardinal symptom of IH is described as postural headache usually aggravating in the upright position and improving in the supine or Trendelenburg position.[3]

There are well-defined diagnostic criteria for spontaneous IH based on clinical and radiological signs.[5] The three main sources for CSF leak are a tear of the spinal dural membrane, rupture of a meningeal diverticulum, and development of a CSF venous fistula. Brain MRI with gadolinium is the most sensitive test for identifying spontaneous IH. Generally, it is difficult to detect the causative CSF leakage. The location of CSF leaks associated with spontaneous IH is almost exclusively spinal, mostly occurring at the thoracic or cervicothoracic junction, in the form of epidural fluid collections, collapse of the dural sac, engorgement of the epidural venous plexus, and meningeal diverticula. Additional neuroimaging when initial studies are nondiagnostic are noninvasive MR myelography and radioisotope cisternography.[6] Common CSF abnormalities in patients with spontaneous IH include a low CSF opening pressure, moderate lymphocytic pleocytosis (up to 50 cells/mm³), the presence of red blood cells, and elevated protein (commonly up to 100 mg/dL). The CSF pleocytosis likely reflects a reactive phenomenon secondary to hydrostatic pressure changes.

Hygromas are believed to be compensatory enlargement of the subdural space due to the loss of CSF volume. The true mechanism of the development of SDH or hygroma due to IH is yet to be hypothesized. However, it has been provisionally described, first, by a rupture of the bridging veins by being pulled away from the dura because of the low ICP and brain descent or, second, by bleeding from the enlarged veins in the subdural zone, which may explain the development of an SDH8. Many prior cases in the literature are shown to have treated the patient with immediate burr hole and decompression of SDH, but this paradoxically worsens the patient due to further lowering ICP. A similar outcome would have happened in our case if the dural tear had not been identified and the patient had been taken up for SDH management.[7] [8]

Typical treatment in the context of spontaneous IH is a noninvasive conservative approach including bed rest in the Trendelenburg position, steroids, hydration, and abdominal binder. Additionally, IV or oral caffeine due to the vasoconstrictive effect and stimulation of the CSF production may be beneficial. As an alternative, an intervention is recommended, consisting of epidural blood patches or surgical repair of the leakage as in our case.

Conclusion

The causes of prolonged postconcussion headaches are often unidentified, of which IH caused by a CSF leak is potentially under-recognized and, more so, under-reported. It should be a differential diagnosis for a case of mild or moderate trauma in association with prolonged postural or permanent headache who is displaying symptoms similar to raised intracranial pressure and a history of significant cervical torsion should be considered for traumatic IH and MRI should be considered relatively early. In such cases, bilateral SDH with mass effect must be ruled out of any CSF leak before attempting the lifesaving decompressive surgery as it may paradoxically lead to further morbidity and mortality of the patient.

Conflict of Interest

None declared.

Authors' Contributions

A.A. is the main author of the case report. S.P. was responsible for data analysis and discussion. R.K.M. was responsible for compilation of images. S.B.S. was responsible for literature review. The manuscript has been read and approved by all the authors and the requirements for authorship has been met and each author believes that the manuscript represents honest work.

Patients' Consent

The authors certify that they have obtained all appropriate patient consent forms. The patients understand that their names and initials will not be published, and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

• References

• 1 Sakka L, Coll G, Chazal J. Anatomy and physiology of cerebrospinal fluid. Eur Ann Otorhinolaryngol Head Neck Dis 2011; 128 (06) 309-316
• 2 Mokri B. The Monro-Kellie hypothesis: applications in CSF volume depletion. Neurology 2001; 56 (12) 1746-1748
• 3 Spears RC. Low-pressure/spinal fluid leak headache. Curr Pain Headache Rep 2014; 18 (06) 425
• 4 Chorobski J. Posioperative intracranial hypotension. J Neurol Neurosurg Psychiatry 1950; 13 (04) 280-287
• 5 Headache Classification Committee of the International Headache Society (IHS) The International Classification of Headache Disorders. 3rd edition. Cephalalgia 2018; 38 (01) 1-211
• 6 Schievink WI. Spontaneous spinal cerebrospinal fluid leaks and intracranial hypotension. JAMA 2006; 295 (19) 2286-2296
• 7 Pettyjohn EW, Donlan RM, Breck J, Clugston JR. Intracranial hypotension in the setting of post-concussion headache: a case series. Cureus 2020; 12 (09) e10526
• 8 Sarrafzadeh AS, Hopf SA, Gautschi OP, Narata AP, Schaller K. Intracranial hypotension after trauma. Springerplus 2014; 3: 153

Publikationsverlauf

Artikel online veröffentlicht:
18. März 2025