Olfactory groove meningioma case reports

A report highlights a case in which a 74-year-old Nigerian male presented with clinical features of anosmia and headache as well as pertinent CT and MRI findings that typically occur in female patients. The study reviews the importance of imaging as a means of achieving a timely diagnosis and accurately measuring the size and magnitude of the disease as it serves as a guide to surgeons when planning for intervention ¹⁾.

A 48-year-old woman with a 2-month history of progressively worsening headaches were referred after a new-onset generalized seizure. On examination, she was found to have diminished olfaction with no additional findings, including no visual or cognitive deficits. Preoperative imaging revealed a large anterior fossa mass originating at the left olfactory groove with leftward extension and prominent anterior and posterior ethmoidal arterial feeders. A left-sided transorbital approach was planned to address the tumor. The lesion was resected without incident using a pure transorbital endoscopic technique. The microscope was brought into the field at the end of the procedure to aid with the hemostasis of the surgical bed. The patient recovered without surgical complications. Histopathology revealed a World Health Organization grade I olfactory groove meningioma. Postoperative imaging confirmed gross total tumor resection without evidence of recurrence. This case highlights the application of the transorbital endoscopic approach in the management of anterior cranial base tumors. Advantages of this approach include minimal invasive access, avoidance of brain retraction, and ease of early tumor revascularization ²⁾

A 52-year-old male with a history of new-onset seizures presented with status epilepticus. Computed tomography and magnetic resonance imaging demonstrated an olfactory groove mass. A keyhole supraorbital-eyebrow approach assisted with a micro inspection tool was performed for tumor resection. A Simpson grade 2 tumor resection was achieved, and histopathology revealed a World Health Organization grade I olfactory groove meningioma. The Postoperative and follow-up courses have been unremarkable, with early postoperative imaging demonstrating no residual tumoral mass. The operative video highlights the advantages of using the micro inspection tool for the visualization of deep lesions ³⁾.

A rare cause of olfactory impairment is olfactory groove meningiomas with insidious onset of non-specific symptoms like headache, olfactory dysfunction, psychiatric symptoms such as depression, personality changes, declining cognitive function, visual disturbances, or seizures. A common complication of surgery is loss of olfactory function. Still, the preservation of olfactory function should be attempted as olfactory loss often has a severe negative impact on quality of life. This report describes a woman with an olfactory groove meningioma and a 10-year history of olfactory impairment. It includes preoperatively and postoperatively extended olfactory testing, a neurosurgical approach to preserve the olfactory function, and postoperative olfactory rehabilitation. After rehabilitation, the patient regained normal olfactory function, even though the right-sided olfactory nerve could not be preserved during surgery. The case demonstrates the importance of performing neuroimaging in selected patients with olfactory loss and a method for preserving and potentially improving postoperative olfactory function ⁴⁾.

A 42-year-old female presented with an olfactory groove meningioma causing progressive vision loss and anosmia. Given the size of the tumor, we opted for a 2-stage surgery: endoscopic endonasal approach (EEA) followed by a craniotomy. Stage I surgery was a transcribriform transplanum EEA using a binostril 4-hand/2 surgeons (ENT and neuro) technique, with the patient positioned supine with the head slightly turned to the right side and tilted to the left, fixed in a 3-pin head clamp, under imaging guidance, in which we drilled out all the affected skull base bone, de-vascularized and debulked the tumor. Stage II surgery was done through a right frontotemporal craniotomy 2 mo later. The surgery and postoperative period were uneventful with no complications and no need for further reconstruction of the skull base. The patient's vision was normalized. Postoperative magnetic resonance imaging (MRI) confirmed a Simpson Grade 1 resection. The rationale behind this staged approach is that we have found when using a transcranial 1-stage approach the brain edema and necessary retraction required for resection lead to brain injury, oftentimes readily identified in the diffusion-weighted imaging MRI which are associated with different degrees of cognitive impairment. The skull base bone involved is usually not removed via transcranial approaches. Despite requiring a second surgery, this staged approach allows a true total resection (including the affected bone) and in the transcranial stage the brain is more relaxed, with less edema, reducing the need for retraction, which may lead to a better outcome ⁵⁾.

A novel case of a World Health Organization grade 3 anaplastic meningioma arising from the olfactory groove in an 83-year-old woman. Molecular and methylation profiling confirm this lesion to be an NF2 subtype, methylation class intermediate type B meningioma. As most meningiomas in this location are indolent SMO subtype lesions, the report suggests that even though rare, aggressive NF2 subtype meningiomas can also occur along the midline anterior skull base ⁶⁾.

Patrikelis et al., present the case of a patient who lost the ability to enjoy humour after the surgical removal of a olfactory groove meningioma, although he was still able to detect it, while at the same time was diagnosed with organic alexithymia. The results indicate that problems in the affective appreciation of humour and in emotionalizing (alexithymic symptoms) may be the result of damage to the ventral-rostral portions of the ACG/mPFC, which prevent the patient from assessing the salience of emotion and motivational information, and generating emotional reactions; as a result he has trouble experiencing emotions, knowing how he and others feel, and enjoy humour ⁷⁾.

A 60-year-old woman was admitted after suffering a subarachnoid hemorrhage (SAH). Neuroimaging data demonstrated an olfactory groove meningioma surrounded by slight edema, but there was no evidence of SAH, although the results of the lumbar puncture demonstrated xanthochromic cerebrospinal fluid. Angiography confirmed the diagnosis of meningioma, but the results of magnetic resonance imaging led the authors to suspect a cavernoma within the meningioma. This diagnosis was established by pathological examination of the resected lesion. The patient did well and was discharged soon after surgery. This very rare association and the propensity of each of these lesions to be revealed by hemorrhage are discussed ⁸⁾

A patient presented with anosmia whose evaluation revealed a large olfactory groove meningioma. She underwent a bifrontal approach for microsurgical gross bilateral excision of the tumor. At her 6-month follow-up examination, her olfaction, as measured by formal testing, had recovered ⁹⁾.

A case of a patient with olfactory groove meningioma associated with multiple aneurysms. The association between intracranial aneurysms and meningiomas is infrequent and perhaps it is due to chance alone; many theories have been formulated to explain it. In the cases with both lesions, meningiomas are more frequently located at the level of the convexity while aneurysms are more often located at the level of the anterior cerebral-anterior communicating artery complex or at the level of the middle cerebral artery ¹⁰⁾