2025 Volume 12 Pages 383-388
Meningiomas are benign tumors outside the brain parenchyma that usually progress slowly but occasionally develop suddenly. We report a 40-year-old woman who presented with symptoms of cerebral herniation within a few hours of the onset of a headache. She felt no particular change until going to bed, when she noticed a headache, vomited, and fell into a coma. At the time of admission, she had a large anisocoria on the right side. A computed tomographic scan revealed a tumor of more than 6 cm in the right frontal region, and cerebral angiography showed tumor staining in multiple branches of the anterior cerebral artery. Intracranial perfusion was slow, suggesting severe intracranial hypertension. An emergency craniotomy was performed, and severe brain swelling was found after the dural incision, requiring an additional craniotomy. The tumor was prone to bleeding, which prolonged the operation time; consequently, the tumor was only partially removed and external decompression with duraplasty was required. After the cerebral swelling improved, tumor-feeding vessel embolization was performed, and then the remaining tumor was completely resected. The pathological diagnosis was atypical meningioma. Eleven months after surgery, the patient can walk by herself despite sensory impairment on the left side, and there has been no evidence of tumor recurrence. Emergency surgery may be required for meningiomas and may have to be performed in a situation where preoperative examinations are not sufficient. In such situations, it is desirable to select an appropriate surgical procedure, including two-stage surgery, and to perform prompt treatment.
Brain tumors generally grow gradually, although the rate of growth does vary, and tumors may present with local symptoms due to direct infiltration or compression of surrounding brain tissue, or symptoms of increased intracranial pressure (ICP) such as headaches and nausea.1,2) Meningiomas, one of the most common extraparenchymal brain tumors, are a type that tends to cause symptoms and progress slowly.3-5) In cases where they cause increased ICP, emergency treatment can be required. Here, we report a case of meningioma that presented symptoms of cerebral herniation within a brief period of time without bleeding, making treatment difficult.
A 40-year-old woman had been healthy and had no history of illness. She prepared her usual meals and ate with her family but noticed a headache before going to bed. A few hours later, she began snoring, then vomiting, and finally became unconscious. On admission to our emergency department, her level of consciousness was Japan Coma Scale (JCS) 200, and a large anisocoria was observed on the right. Her breathing was irregular and snoring, and her condition progressed to decerebrate posturing. A computed tomographic scan of the head revealed a solid tumor measuring approximately 6 cm in size in the right frontal region with perifocal edema and unclear visualization of the subarachnoid space around the midbrain (Fig. 1A and B). Diffusion-weighted imaging on magnetic resonance imaging (MRI) showed high signals in the splenium of the corpus callosum, bilateral thalamus, bilateral hippocampi, and dorsal midbrain (Fig. 1C and D), and the apparent diffusion coefficient map showed signs of hyperacute infarction with diffusion restriction. In addition, the right lateral ventricle was narrowed due to compression by the tumor, the left lateral ventricle was enlarged, and the third ventricle to the cerebral aqueduct was also compressed, causing cerebrospinal fluid circulatory disorders (Fig. 1E). However, the T2*-weighted imaging did not reveal any low signal intensity suggestive of intratumoral hemorrhage (Fig. 1F). Magnetic resonance angiography showed poor visualization of some bilateral posterior cerebral arteries in the ambient cisterns, suggesting stenosis due to transtentorial herniation (Fig. 1G and H). After intubation in the emergency department, cerebral angiography was performed under artificial respirator management. Tumor staining was observed from multiple branches of the right anterior cerebral artery, but no clear staining from the external carotid artery system. The inflow of contrast agent into the skull was slow and the perfusion time was long, indicating severe elevation of ICP (Fig. 2A-D). The patient was subsequently transferred to the operating room, where a bilateral frontal craniotomy with greater expansion on the right side was performed; as the brain was severely swollen, an additional craniotomy was performed on the right temporal region. Because the tumor was large, it was impossible to remove as a single mass. Furthermore, tumor feeders were flowing in from deep within the tumor, making it impossible to coagulate them before removing the tumor; accordingly, the tumor was removed little by little using ultrasound echo while performing hemostasis procedures. As a result, the removal was prolonged, with the operation time exceeding 24 hours, and there was more intraoperative blood loss, requiring a blood transfusion. In the end, dura formation was added with some of the tumor remaining, and the wound was closed with external decompression. The intraoperative bleeding comprised 2950 mL; blood was transfused with 20 units of irradiated red blood cells, leukocytes reduced 2, 18 units of fresh frozen plasma 1, and 30 units of irradiated platelet concentrate, leukocytes reduced; and the total operation time was 30 hours and 54 mins.
Non-contrast axial computed tomography scans on admission revealed a large solid tumor with perifocal edema in the right frontal region and unclear visualization of the subarachnoid space around the midbrain (A, B). Diffusion-weighted images showed high signals in the splenium of the corpus callosum, bilateral thalamus, bilateral hippocampi, and dorsal midbrain (C, D), and fluid-attenuated inversion recovery image revealed a compressed ventricular system (E), but T2*-weighted image demonstrated the absence of intratumoral hemorrhage (F). Magnetic resonance angiography showed midline-shifted anterior cerebral arteries (G) and poor visualization (arrows) of the bilateral posterior cerebral arteries in the ambient cistern (H).
Preoperative right common carotid angiograms revealed tumor staining from multiple branches of the right anterior cerebral artery, otherwise poor contrast visualization, and delayed perfusion time (A, C; arterial phase, B, D: venous phase). Coil embolization performed before the second surgery reduced inflow to the tumor (E, F: pre, G, H: post).
After the operation, the patient was managed in the intensive care unit, and a tracheotomy was also required. One and a half months after the brain swelling had subsided, nutrient vascular embolization with coil was performed (Fig. 2E-H), and the remaining tumor was completely removed and cranioplasty performed. Histopathological examination of the resected tumor revealed proliferating tumor tissue with a sheet-like or tangled structure, and a partially spiral structure (Fig. 3A). The tumor cells had a high nuclear/cytoplasmic ratio, mild nuclear enlargement, small nucleoli, and a maximum number of mitotic figures of 4/10 high-power fields (×400) (Fig. 3B). The Ki-67 labeling index was approximately 10%, and the tumor was diagnosed as atypical meningioma.
Histopathological images of hematoxylin and eosin staining revealed tumor tissue proliferating in a sheet-like structure and partially in a spiral structure (A), and tumor cells with mild nuclear enlargement and mitotic figures (B).
The patient then became conscious, was able to eat, the tracheal stoma was closed, and she became able to speak. She was transferred to another hospital with a modified Rankin Scale 3 for continued rehabilitation. She was subsequently discharged home, and as of 11 months after surgery, there has been no recurrence of a tumor on MRI (Fig. 4A-C).
Axial T1-weighted magnetic resonance images with gadolinium at 11 months after the second surgery demonstrated no recurrence of tumor without infarction (A-C).
Meningiomas are a type of brain tumor that progresses chronically,3-5) but in rare cases, associated symptoms begin suddenly and worsen rapidly. The causes of such rapid symptom development include rapid tumor growth,6) worsening peripheral edema,7) bleeding within or around the tumor,8,9) and acute non-communicating hydrocephalus due to cerebrospinal fluid circulatory disorders. Consequently, symptoms such as sudden intracranial hypertension, loss of consciousness, and convulsions occur, and in some cases, emergency surgical treatment to reduce pressure may be necessary.6,7,10-13)
In this case, computed tomography findings at the time of admission suggested that the patient should have been experiencing a headache and the feeling of a heavy head for some time, but she had been working as a housewife on the day the symptoms appeared, had prepared and eaten dinner, and her family did not notice anything abnormal. The patient first complained of a headache only before going to bed, and about 5 hours later, she began snoring and lost consciousness, and was taken to the hospital.
The tumor was suspected a meningioma in the right frontal falx, measuring over 6 cm in long diameter and accompanied by a tentorial herniation, but no tumor-related bleeding was observed. As a potential cause for the rapid deterioration of symptoms, epilepsy was considered; nonetheless, no obvious seizure episodes were observed during the course. It is also noted that preoperative arterial spin labeling imaging, which can detect increased blood flow during seizures, would have been useful for differential diagnosis. Due to the urgent need for decompression surgery, this examination could not be performed. Therefore, although it remains speculative, it is thought that the sudden onset of symptoms may have been caused by the tumor compressing the brain and obstructing cerebrospinal fluid circulation in the cerebral aqueduct and the third ventricle, leading to rapid intracranial hypertension.
Tyagi et al.14) reviewed 44 cases of meningiomas that underwent emergency surgery over a 5-year period but did not report the time from admission to surgery for emergency surgery. The mean preoperative Glasgow Coma Scale (GCS) was 13, and the neurological severity of those cases was considered relatively mild compared to this one. A GCS of <15 and postoperative complications are reportedly associated with poor patient outcomes.14) Our patient had a GCS of 4 at the time of admission, predicting a poor prognosis. Although there have been occasional reports of cases requiring emergency surgery due to intratumoral hemorrhage or acute subdural hematoma around the tumor, there have been no reports of a patient falling into a semi-coma within a short period of time, as in this case, without tumor-related bleeding.
"Oncogenic emergency" is a general term for symptoms that require emergency treatment due to malignant tumors.15,16) Fujita et al.17) reported on oncogenic emergencies related to brain tumors at a single institution, reviewing 23 cases in which emergency surgery was performed within 24 hours of either emergency transport or a scheduled surgery due to a sudden deterioration of neurological symptoms. They found such emergencies to account for 3.8% of all brain tumor surgeries, and to be more common in children under 15 years of age. Of the 15 cases, most were malignant tumors, including 6 gliomas and 6 metastatic brain tumors; none were meningiomas. The authors stated that central nervous system tumors, once they develop, are prone to irreversible neurological sequelae, so it is extremely important to select an appropriate surgical method and treat them promptly.17)
When this patient was admitted, her consciousness level was JCS 200, she was in a semi-coma state, and her respiratory condition subsequently deteriorated, so she underwent endotracheal intubation in the emergency room to manage ICP, and respiratory management was started. Although there was a large anisocoria on the right, the tumor was thought to be a meningioma; accordingly, we considered it necessary to first evaluate the tumor's nutrient vessels and venous system to perform the surgery safely and conducted an angiogram of the common carotid artery on the affected side only before performing emergency surgery.
The basic treatment for a meningioma is removal, but this is not always possible in an emergency. It has been reported that external decompression and control of ICP are also useful treatments.18,19) To achieve decompression, a wide craniotomy was performed on both sides, but brain swelling was significant after the craniotomy. To control brain pressure, an osmotic diuretic was administered, the head was elevated, and mild hyperventilation was used to maintain arterial partial pressure of carbon dioxide at a level below 30-35 mmHg. Subsequently, tumor removal was started, but the brain swelling remained severe and bleeding could not be controlled. An additional craniotomy of the right temporal region improved the patient's condition and allowed the surgery to continue.
Although it would have been desirable to remove the entire tumor in one operation, the operation took a long time and required a large amount of transfused blood; consequently, a two-stage operation was performed. In the second operation, preoperative tumor embolization completely removed the tumor without blood transfusion, and the patient was afterward able to return to an independent life. Emergency surgery performed to save a life is different from surgery in normal times and requires a response according to the situation with instantaneous decision-making; as such, the courage to choose a two-stage surgery is also considered important.
ConclusionsWe experienced a case of a meningioma patient who fell into a coma within a short time and was rushed to the hospital. In such cases, it is necessary to select an appropriate surgical method, perform the surgery promptly, and make immediate decisions such as stopping the surgery midway and switching to a two-stage surgery based on intraoperative findings.
Informed consent was obtained from the patient involved in this study.
All authors have no conflict of interest.
