Acute Presentation of Vestibular Schwannoma Secondary to Intratumoral Hemorrhage: A Case Report and Literature Review

Intratumoral Hemorrhage in Vestibular Schwannomas After Stereotactic Radiosurgery: Multi-Institutional Study

BACKGROUND AND OBJECTIVES

Intratumoral hemorrhage (ITH) in vestibular schwannoma (VS) after stereotactic radiosurgery (SRS) is exceedingly rare. The aim of this study was to define its incidence and describe its management and outcomes in this subset of patients.

METHODS

A retrospective multi-institutional study was conducted, screening 9565 patients with VS managed with SRS at 10 centers affiliated with the International Radiosurgery Research Foundation.

RESULTS

A total of 25 patients developed ITH (cumulative incidence of 0.26%) after SRS management, with a median ITH size of 1.2 cm 3 . Most of the patients had Koos grade II-IV VS, and the median age was 62 years. After ITH development, 21 patients were observed, 2 had urgent surgical intervention, and 2 were initially observed and had late resection because of delayed hemorrhagic expansion and/or clinical deterioration. The histopathology of the resected tumors showed typical, benign VS histology without sclerosis, along with chronic inflammatory cells and multiple fragments of hemorrhage. At the last follow-up, 17 patients improved and 8 remained clinically stable.

CONCLUSION

ITH after SRS for VS is extremely rare but has various clinical manifestations and severity. The management paradigm should be individualized based on patient-specific factors, rapidity of clinical and/or radiographic progression, ITH expansion, and overall patient condition.

Intratumoral hemorrhage in vestibular schwannomas after stereotactic radiosurgery

OBJECTIVE

Vestibular schwannomas (VSs) are benign tumors of the cerebellopontine angle that are typically managed with stereotactic radiosurgery (SRS). Intratumoral hemorrhage (ITH) of VSs is a rare occurrence that results in worsening vestibular and new cranial nerve deficits. Few reports have described the management and outcomes of this entity after SRS. To further delineate the incidence and impact of this event, the authors performed a retrospective review of their VS SRS patients at a single center.

METHODS

Between 1987 and 2022, 2058 patients with VSs underwent Gamma Knife radiosurgery (GKRS) at the University of Pittsburgh Medical Center. The authors performed a review of the prospectively maintained VS database at their center to identify patients with ITH. The presentation, management, and clinical and imaging outcomes of the patients are reported.

RESULTS

A total of 1902 VS patients had sufficient clinical and imaging follow-up data. Five Koos grade III (n = 1) and IV (n = 4) VS patients developed ITH after GKRS, resulting in a cumulative incidence rate of 0.26%. The age at presentation ranged from 62 to 79 years, and 3 patients were male. The time from VS diagnosis to GKRS ranged from 1 to 13 months, and the time from GKRS to ITH ranged from 2 to 130 months. Three patients had bleeding risk factors. One patient required urgent surgical intervention due to the ITH volume, while the other 4 patients were initially observed. Three patients remained stable and required no delayed intervention; 1 patient required delayed resection because of symptom progression and hemorrhagic expansion. Histopathological analysis revealed multiple fragments of S-100-positive cells, hemorrhage, and hemosiderin-laden macrophages. At last follow-up, 4 patients had clinically improved and 1 patient remained stable.

CONCLUSIONS

ITH after VS radiosurgery is a rare phenomenon with a cumulative incidence rate of 0.26% in this series. Patient-tailored management in the form of observation or resection is based on patient presentation, acuity, and ITH size.

Hemorrhagic schwannoma of the trochlear nerve: Case report and a review of the literature

Background

Schwannomas of the trochlear nerve with the absence of systemic neurofibromatosis are considerably uncommon, especially complicated by intra-tumoral hemorrhage. Due to the lack of typical clinical manifestations and imaging findings, a definite diagnosis of trochlear schwannomas before surgery is particularly difficult.

Case presentation

We report the case of a 64-year-old female patient who presented with a unilaterally intermittent headache of 2-month duration and without a remarkable neurological deficit at admission. Imaging studies revealed a well-demarcated cystic-solid lesion with mixed signals beside the brainstem and suprasellar cisterna. The patient underwent a surgical operation with total resection of the tumor by a subtemporal surgical approach. The tumor was intraoperatively found to originate from the trochlear nerve and was pathologically confirmed as a hemorrhagic schwannoma with cystic degeneration.

Conclusions

We describe this case in detail and conduct a concomitant survey of the literature, summarizing the clinical presentations, radiological features, surgical treatment, and the possible mechanisms of hemorrhage in relevance to trochlear nerve schwannoma.

Hemorrhagic vestibular schwannoma: a case example of vestibular apoplexy syndrome. Illustrative case

BACKGROUND

Acute intratumoral hemorrhage within a vestibular schwannoma, or vestibular apoplexy, is a rare condition. Unlike the typical insidious vestibulopathy typically caused by vestibular schwannoma growth, patients with vestibular apoplexy have an acute and severe presentation with nausea and emesis in addition to severe vertigo and hearing loss. Here, the authors present an illustrative case demonstrating this rare clinical condition and an operative video detailing the surgical management.

OBSERVATIONS

A 76-year-old man presented to the emergency department with acute-onset dizziness, left-ear fullness, double vision, gait ataxia, emesis, and facial numbness. Imaging revealed a 2.8-cm hemorrhagic left cerebellopontine angle lesion extending into the left internal auditory canal, consistent with hemorrhagic vestibular schwannoma. The patient subsequently underwent a retrosigmoid craniotomy for resection of the hemorrhagic mass, and by 1 month after surgery, all his presenting symptoms had resolved, allowing his return to daily activities.

LESSONS

Vestibular schwannomas typically present with decreased hearing and chronic vestibulopathy. Acute presentation should raise the suspicion for an apoplectic event, and surgical debulking may lead to improvement in most vestibular symptoms.

Intratumoral hemorrhage in jugular foramen schwannoma after stereotactic radiosurgery: A case report

Background:

Clinically significant intratumoral hemorrhage is a rare complication of stereotactic radiosurgery (SRS) for benign tumors.

Case Description:

Here, we present the case of a 64-year-old man who underwent SRS for a relatively large dumbbell-shaped left jugular foramen schwannoma (JFS) and thereafter developed intratumoral hemorrhage. On post-SRS day 3, he developed lower cranial nerve palsies with radiographically evident tumor expansion. His neurological conditions had gradually improved thereafter; however, he suddenly developed headache, dizziness, and mild hearing deterioration at 7 months due to intratumoral hemorrhage. We managed the patient conservatively, and eventually, his symptoms improved except for slight ataxia and hearing deterioration. Follow-up images at 4 years from SRS demonstrated significant tumor shrinkage. This is the first report describing intratumoral hemorrhage after SRS for JFS.

Conclusion:

Transient expansion of the tumor and subsequent venous stasis around the tumor may have played a role in the hemorrhage. Intratumoral hemorrhage should be considered as a rare, but potential complication of SRS for JFSs.

Oculomotor Nerve Palsy Due to Unusual Causes

BACKGROUND

An isolated oculomotor nerve (CN III) palsy is a diagnostic concern because of the potential for serious morbidity or life-threatening causes. We present 5 unusual causes of oculomotor nerve palsy that escaped initial diagnosis in order to raise awareness of their associated features that will facilitate correct diagnosis.

METHODS

This study consisted of a retrospective analysis of clinical features and imaging of 5 patients who were referred for neuro-ophthalmologic evaluation with presumed diagnosis of oculomotor nerve palsy of unknown reasons.

RESULTS

A complete CN III palsy and an inferior division CN III palsy were diagnosed with a schwannoma in the cavernous sinus and orbital apex portion, respectively; a middle-aged woman with aberrant regeneration was found to have a small meningioma; an adult man with ptosis was diagnosed with cyclic oculomotor paresis with spasms; and a patient after radiation was diagnosed with neuromyotonia.

CONCLUSIONS

Localizing the lesion of oculomotor nerve palsy and careful examination of the imaging is crucial. Aberrant regeneration, cyclic pupil changes, and past medical history of amblyopia, strabismus, or radiation are also very helpful for diagnosis.

Vestibular neuronitis in a vestibular schwannoma patient

This is a unique presentation of an acute vestibular syndrome (AVS) caused by vestibular neuronitis (VN) of a vestibular nerve (CNVIII) already affected by vestibular schwannoma (VS). A 48-year-old patient, formerly diagnosed with an intracanalicular VS, presented with AVS. The patient underwent clinical and neurotological examination including video Head Impulse Test and a 4-hour delayed-enhanced 3D-FLAIR MRI using intravenous gadolinium. Clinical and neurotological findings were consistent with VN of the CNVIII formerly diagnosed with VS. A 4-hour delayed-enhanced 3D-FLAIR MRI showed significant enhancement of the labyrinth also indicating VN of the same nerve affected by VS. Pragmatic corticosteroid therapy and vestibular exercises were applied resulting in satisfactory recovery of the patient. As vestibular symptoms are common in VS patients, investigating another cause of dizziness and vertigo in VS patients can be marginalized. Nevertheless, VS presenting as AVS is very unusual. VN should not be overlooked as a possible cause of acute vertigo in a patient previously diagnosed with VS.

"When the Benign Bleed" Vestibular Schwannomas with Clinically Significant Intratumoral Hemorrhage: A Case Series and Review of the Literature

Vestibular schwannomas (VSs) are slow-growing benign neoplasms commonly located at the cerebellopontine angle. Although clinically significant hemorrhagic VSs are rarely encountered with only 75 patients previously reported, they could be life threatening. We discuss the presentation and outcomes of three patients with hemorrhagic VS as well as review the literature for this phenomenon. Consecutive adult patients with a histologically proven diagnosis of VS over a 9-year period were retrospectively reviewed. Fifty adult patients were identified with three (6%) having clinically significant intratumoral hemorrhage. This was defined as patients having acute to subacute symptoms with frank radiological evidence of hemorrhage. The mean age of diagnosis was 62 ± 9 years and the male-to female ratio was 2:1. The mean duration of symptoms, namely headache, vertigo, and sensorineural hearing impairment, was 26 ± 4 days with one patient presenting with acute coma. Retrosigmoid craniotomy for tumor resection was performed for all patients. Histopathological examination revealed extensive areas of microhemorrhage with considerable macrophage infiltration. All three patients were discharged with no additional neurological deficit and good functional performance. Clinically significant hemorrhagic VSs are rare, and patients may present with acute to subacute (i.e., within a month) symptoms of hearing loss headache, facial, or trigeminal nerve palsy. Macrophage infiltration is frequently encountered in tumor specimens and reflects the pivotal role of chronic inflammation in their pathophysiology. Surgical resection can lead to good outcomes with timely intervention.

Hemorrhagic Vestibular Schwannoma: Case Report and Literature Review of Incidence and Risk Factors

Hemorrhagic vestibular schwannoma (HVS) consisting of acute intratumoral and subarachnoid hemorrhage presents with acute nausea, vomiting, facial numbness, headache, loss of consciousness, and significant functional impairment of the facial and vestibulocochlear nerves. The current case is of a 31-year-old man who was presented with acute left lateral suboccipital headache, vomiting, ataxia, and loss of consciousness. Brain CT revealed a large iso-intense lesion with internal hematoma at the left cerebellopontine angle in association with internal acoustic canal dilation. In addition, MRI confirmed a 32 x 25 x 26 mm vestibular schwannoma (VS) with 20 x 15 x 5 mm intratumoral hematoma. The patient had undergone left lateral suboccipital craniotomy and microscopic tumor resection. Pathological findings revealed that his lesions were VS. The average incidence of HVS is around 2.15 cases per year worldwide. Therefore, HVS incidence in proportion to VS is very low and consequently rare.