Meningiomas of Meckel's cave

Dumbbell-shaped meningioma of Meckel's cave mimicking trigeminal schwannoma: A case report

INTRODUCTION AND IMPORTANCE

Several meningioma cases arising through Meckel's cave (MC) at the middle and posterior fossa have been reported. However, few relevant meningiomas have been observed with a dumbbell shape.

PRESENTATION OF CASE

We report a rare case of a 36-year-old woman with a meningioma of MC with a typical dumbbell-shaped, schwannoma-like presentation on magnetic resonance imaging (MRI), resulting in a misleading differential diagnosis.

CLINICAL DISCUSSION

In this case report, we discuss the characteristics of meningioma of MC observed on MRI and our surgical approach to this condition.

CONCLUSION

This tumor was able to mimic a trigeminal schwannoma both clinically and radiographically. This case report has been reported in line with the SCARE 2020 criteria [1].

Dural relationships of Meckel cave and lateral wall of the cavernous sinus

OBJECT

The purpose of this study was to elucidate the anatomy of the trigeminal nerve (cranial nerve [CN] V), Meckel cave (MC), and lateral wall of the cavernous sinus (CS).

METHODS

Ten fresh cadaver heads (20 sides) and 2 middle fossa embalmed specimens were removed, decalcified, sectioned, stained, and studied microscopically.

RESULTS

In the MC, the posterior fossa meningeal dura extended into the middle fossa surrounding CN V. The average medial length of the MC was 16.7 mm and the lateral length was 13.5 mm. The dural roof of MC was thicker than its floor and was covered by a paw-shaped fibrous tissue extending from the tentorium to the ganglion (in 100% of specimens). Between the dural sleeve of the MC and venous space of the CS, a separate fibrous wall could be identified in 45% (9 of 20) extending between the tentorium and the floor of the CS. The mean length of CN V in the MC proximal to the posterior margin of the Gasserian ganglion was 11.8 mm. The mean length of CN V1 was 19.4 mm; V2, 12.3 mm; and V3, 7.4 mm distal to the anterior margin of the ganglion. The periosteal dura followed the bone of the middle fossa and was continuous with the extracranial periosteum. The lateral dural wall of the CS consisted of a medial (membranous) and a lateral wall. The latter was separated into a thin outer layer and a thicker fibrous inner layer that became thinner as it extended posterolaterally.

CONCLUSIONS

The MC is an extension of the posterior fossa dura with intricate relationships with the surrounding dural layers.

Gamma Knife surgery for trigeminal pain caused by benign brain tumors

Object

The authors report the effects of Gamma Knife surgery (GKS) on benign tumor–related trigeminal pain in patients who underwent follow-up for a mean 57.8 months.

Methods

From 1999 to 2004, 21 patients with benign tumor–related trigeminal pain (12 meningiomas and 9 schwannomas) underwent GKS as a primary or repeated treatment. These patients harbored tumors within the radiosurgical target area. For meningiomas, the mean radiosurgical treatment volume was 8.2 ml (range 1.1–21 ml), and the mean radiosurgical tumor margin dose was 12.7 Gy (range 12–15 Gy); for schwannomas, the mean volume was 5.6 ml (range 2–9.2 ml), and the mean marginal dose was 13 Gy (range 11.5–16 Gy). Seven patients underwent retreatment for recurrent or persistent pain; the ipsilateral trigeminal nerve or ganglion was identified and a mean maximal dose of 60.7 Gy (range 40–70 Gy) was delivered to these targets. In 1 patient undergoing retreatment, the margin dose was 12 Gy. The mean age at the time of radiosurgery was 54.5 years (range 18–79 years).

Results

The mean follow-up period was 57.8 months (range 36–94 months). Overall, 12 (57%) of 21 patients experienced pain relief without medication after the first GKS and the mean time to drug discontinuation was 10.5 months (range 2–24 months). Initial pain improvement was noted in 17 patients (81%) with a mean time of 3.7 months (range 1 week–10 months) after GKS. Eight patients underwent repeated GKS for persistent and recurrent pain. Four patients (50%) had complete pain relief. The final results of the first and repeated GKS were excellent in 16 patients (76%), and in only 1 patient did GKS fail, and this patient later underwent open surgery. For all 21 patients (100%), control of tumor growth was documented at a mean of 46 months after GKS. Three of 6 patients with pre-GKS facial numbness reported improvement, but 4 suffered new facial numbness after repeated GKS.

Conclusions

Gamma Knife surgery appears to be an effective tool to treat benign tumor–related trigeminal pain and control tumor growth. Repeated GKS targeting the trigeminal root or ganglion can be considered a tool to enhance the efficacy of pain management if pain persists or recurs, but the optimum treatment dose needs further investigation.

Meningioma arising from the trigeminal nerve: a case report and literature review

We report a 69-year-old woman with a meningioma who presented with a 9-month history of progressive facial numbness in the distribution of the left mandibular nerve and left facial palsy. Magnetic resonance imaging revealed a mass in and around the left Meckel's cave (MC). The tumor was totally resected through a lateral suboccipital and subtemporal combined approach. It appeared to be a schwannoma, because it adhered firmly to the cisternal portion of the trigeminal nerve without dural attachment. Histopathological examination revealed that it was a meningothelial meningioma. We concluded that the tumor originated from the arachnoid cap cells within the trigeminal nerve sheath, not from the dura mater in the MC.

The importance of routine magnetic resonance imaging in trigeminal neuralgia diagnosis

The aim of the study was to determine the frequency of structural lesions diagnosed on magnetic resonance imaging (MRI) in a sample of patients with trigeminal neuralgia (TN) and to compare history and clinical features between the groups with and without structural lesions. Clinical records and MRI findings of 42 consecutive patients diagnosed with TN at the National Dental Centre, Singapore, and who underwent routine MRI examinations at diagnostic workup between April 1997 and March 1999 were retrospectively studied. Of these, 6 (14.3%; 95% confidence interval, 0 to 28.8%) were diagnosed with an associated structural lesion. Mean age of the group with structural lesions was 53.3 years (standard deviation, 10.9 years) at presentation, there was female predominance (M:F = 1:2), and all (100.0%) gave a typical pain history and had unilateral involvement of a single division of the trigeminal nerve. Two patients (33.3%) had other cranial nerve abnormalities. Three patients (50.0%) had complete, 2 patients (33.3%) had partial, and 1 patient (16.7%) had poor response to medical therapy. None of these variables was statistically different from the group without structural lesions (cranial nerve abnormalities were not compared). In conclusion, the frequency of structural lesions associated with TN in our sample was relatively high. It is not possible to reliably identify high risk patients for selective MRI indication on the basis of history and clinical features. It may be prudent to consider routine MRI for all patients with TN to exclude structural lesions.

Long-term outcome after gamma knife surgery for secondary trigeminal neuralgia

OBJECT

This study was directed to evaluate the potential role of gamma knife surgery (GKS) in the treatment of secondary trigeminal neuralgia (TN). The authors have identified three anatomicoclinical types of secondary TN requiring different radiosurgical approaches.

METHODS

Pain control was retrospectively analyzed in a population of patients harboring tumors of the middle or posterior fossa that involved the trigeminal nerve pathway. This series included 53 patients (39 women and 14 men) treated using GKS between July 1992 and June 1997. The median follow-up period was 55 months. Treatment strategies differed according to lesion type, topography, and size, as well as visibility of the fifth cranial nerve in the prepontine cistern. Three different treatment groups were established. When the primary goal was treatment of the lesion (Group IV, 46 patients) we obtained pain cessation in 79.5% of cases. In some patients in whom GKS was not indicated for treatment of the lesion, TN was treated by targeting the fifth nerve directly in the prepontine cistern if visible (Group II, three patients) or in the part of the lesion including this nerve if the nerve root could not be identified (Group III, four patients). No deaths and no radiosurgically induced adverse effects were observed, but in two cases there was slight hypesthesia (Group IV). The neuropathic component of the facial pain appeared to be poorly sensitive to radiosurgery. At the last follow-up examination, six patients (13.3%) exhibited recurrent pain, which was complete in four cases (8.8%) and partial in two (4.4%).

CONCLUSIONS

The results of GKS regarding facial pain control are very similar to those achieved by microsurgery according to series published in the literature. Nevertheless, the low rate of morbidity and the greater comfort afforded the patient render GKS safer and thus more attractive.

Suprameatal extension of the retrosigmoid approach: microsurgical anatomy

OBJECTIVE

This study was conducted to determine whether removing the bony prominence located above the porus of the internal acoustic meatus, called the suprameatal tubercle, and surrounding bone using the retrosigmoid approach would aid in the exposure of tumors that are located predominantly in the cerebellopontine angle but that also extend into the middle cranial fossa in the region of Meckel's cave and thus avoid the need for a supratentorial craniotomy.

METHODS

Thirty cerebellopontine angles from 15 cadaveric heads examined using 3 to 40x magnification provided the material for this study. A retrosigmoid craniotomy was completed and the exposure obtained before and after removing the suprameatal tubercle, and the surrounding bone was examined. In some cases, Meckel's cave and the tentorium lateral to the porus of Meckel's cave was opened to aid in the exposure.

RESULTS

Removing the suprameatal tubercle and surrounding bone increased the exposure an average of 10.3 mm (range, 8.0-13.0 mm) forward of the exposure, which could be obtained without suprameatal drilling. The extent of bone removal was limited on the lateral side by the posterior and superior semicircular canals and their common crus.

CONCLUSION

The suprameatal extension of the retrosigmoid approach will permit removal of some tumors that are located mainly in the posterior fossa but that extend into the middle fossa in the region of Meckel's cave. The exposure can be increased by opening the superior petrosal sinus as it crosses in the upper margin of the porus of Meckel's cave and by opening the tentorium lateral to Meckel's cave.

Juxtaorbital en plaque meningiomas. Report of four cases and review of literature

Juxtaorbital spheroid wing or ridge meningiomas are the most common of the basal meningiomas. These are at times meningiomas en plaque, which in most patients do not have significant intracranial component. This article reviews the literature on en-plaque meningiomas and discusses the role of MR imaging and CT in the diagnosis of en-plaque meningiomas of the paraorbital region. The role of fat-suppression, gadolinium-enhanced, T1-weighted MR imaging is emphasized.

Surgical management of meningiomas originating in Meckel's cave

OBJECTIVE

To define the difference of meningiomas that originate in the area of Meckel's cave (MC) (primary MC meningiomas) in regard to the different surgical approaches and postoperative results.

METHODS

A retrospective analysis of all meningiomas involving the cranial base displayed 21 cases of meningiomas originating in MC (primary MC meningiomas). These cases were classified according to the tumor extension in four different types: Type I, tumors mainly confined to MC; Type II, MC meningiomas with extension into the middle fossa; Type III, MC meningiomas with extension into the posterior fossa; and Type IV, MC meningiomas with extension into both middle and posterior fossae.

RESULTS

Trigeminal neuralgia resolved in all cases in this series, despite tumor type. Trigeminal hypesthesia showed postoperative improvement only in Type III MC meningiomas. In Types I and III, total removal without further morbidity was frequently achieved. Cavernous sinus infiltration, especially in Types II and IV, limited (in some cases) the extent of tumor extirpation.

CONCLUSION

Types I, II, and III MC meningiomas have a good prognosis. In most cases, very good outcomes are achieved. Radical tumor removal can usually be achieved without further morbidity and with postoperative improvement of the preexisting symptoms, especially in Types I and III MC meningiomas. On the contrary, Type IV MC meningiomas are usually only subtotally resected. Surgery in such cases may carry a high risk of additional morbidity, especially with regard to the IIIrd, IVth, and VIth cranial nerves. The postoperative outcome regarding facial pain in cases of all tumor types is usually very good. Trigeminal hypesthesia may persist after tumor removal in the majority of cases.

An extensive cranial base meningioma extending bilaterally into Meckel's cave: case report

OBJECTIVE AND IMPORTANCE

A patient with an extensive cranial base meningioma that included bilateral invasion of Meckel's cave underwent surgical resection and had an unexpected rare complication, malocclusion from bilateral trigeminal dysfunction.

CLINICAL PRESENTATION

A 19-year-old male patient was admitted to our hospital with alternating painful ophthalmoplegia. He had been blind since the age of 10 years. At the time of admission, neurological findings included bilateral visual loss and optic atrophy. Magnetic resonance images showed an extensive tumor located at the planum sphenoidale, tuberculum sellae, and bilaterally at Meckel's cave and the medial tentorial incisura.

INTERVENTION

The patient underwent a two-stage operation. During the first procedure, the masses in the planum sphenoidale, tuberculum sellae, and the left side of Meckel's cave were excised intradurally. At the second operation, the mass in the right side of Meckel's cave was excised extradurally and the tentorial mass was removed intradurally. The patient's postoperative course was complicated by bilateral trigeminal nerve dysfunction, which caused malocclusion.

CONCLUSION

Bilateral dysfunction of the trigeminal nerve may cause a number of problems. Thus, extreme caution must be taken to preserve the function of this nerve.

[Diagnosis and treatment of atypical facial pain-a review.]

Atypical facial pain is a collective term used for otherwise unclassifiable pain syndromes of the face. It describes mostly unilateral lancinating and burning pain, which is constantly present but fluctuating in intensity and may be accompanied by dys-or paraesthesias over a period of several years. Women are more often affected than men. A strikingly large number of invasive investigative procedures are performed before the final diagnosis is established. Psychopathological abnormalities are frequent and do not consist solely in masked depression. To date there is no cure for atypical facial pain. Most frequently tricyclic antidepressants such as amitriptyline and imipramine, MAO inhibitors or anticonvulsives such as carbamazepine and phenytoin are used, which only alleviate the pain. This also holds true for behaviour therapy, which should be the first-line treatment. Any invasive intervention should be avoided. In the differential diagnosis atypical facial pain should be distinguished from cervicogenic or cluster headache, and also from intracranial tumours of the trigeminal nerve or the cerebellar-pontine angle, erosive tumors of the base of the skull, orbitas and nasopharynx.

Trigeminal neuralgia: differentiation between intracranial mass lesions and ordinary vascular compression as causative lesions

We investigated 164 patients who presented with trigeminal neuralgia as their initial symptom at our institute. Twenty-two patients (13.4%) had intracranial causative lesions other than vascular compression. There were 19 tumors (10 epidermoids, 5 meningiomas, and 4 neurinomas) and 3 vascular lesions (2 arteriovenous malformations and 1 aneurysm). Eleven patients (50%) demonstrated only trigeminal neuralgia without any other neurological deficits. Preoperative computed tomography could not identify any causative lesions in 6 of these 22 patients. In 3 of the 6 patients, a causative lesion was clearly detected only by magnetic resonance imaging, while in 1 of the 6 patients an arteriovenous malformation was detected by angiography alone. Intraoperatively tumor was encountered in 3 cases even though preoperative computed tomography could not detect any apparent causative lesions. A higher incidence of hypesthesia in the trigeminal nerve regions as well as a reduced corneal reflex was noted in patients with a mass lesion compared to those with vascular compression. We thus conclude that magnetic resonance imaging should be performed on all patients who complain of trigeminal neuralgia in order to rule out mass lesions, however, angiography is still considered useful for the diagnosis of some vascular lesions.

Meningiomas of the cranial base

Treatment objectives for meningiomas of the cranial base include relief of neurologic disability and prevention of clinical progression or recurrence with the least morbidity. Recent advances in skull base surgical techniques, through an appreciation of skull base anatomy and institutional specialization, have contributed major improvements to the outlook for patients with these tumors, and previously inoperable cases may now often be removed completely with acceptable risk. Since significant morbidity may be incurred during surgical resection of these difficult lesions, especially in terms of cranial nerve dysfunction, the value of aggressive surgical resection must be weighted against the often indolent natural history of these lesions, and must be individualized in each patient. Completeness of resection is the major prognostic factor determining the outcome of patients with typical benign meningiomas in terms of length of survival, risk of recurrence, and neurological disability. Various means of prognosticating the growth potential of a given tumor are being investigated, though none have yet been confirmed for their predictive value in typical, histologically benign meningiomas. The role of external beam radiotherapy has not been subjected to adequately controlled, prospective studies, and there is currently insufficient followup to assess the risks and benefits of stereotactic radiosurgery. Advances in the clinical management of tumors of the skull base has had perhaps the greatest impact for patients with meningiomas who constitute a large portion of tumors seen in these locations. Although the majority have benign histological features, skull base meningiomas can present a formidable challenge due to their proximity to vital structures, surgical inaccessibility, and occasional aggressive features. The combination in recent years of advances in skull base surgical techniques, adjuvant therapy, and rehabilitation methods have dramatically improved the outcome for these tumors.

Atypical facial pain--application of the IHS criteria in a clinical sample

Atypical facial pain is a residual category for otherwise unclassifiable pain syndromes in the facial region. In 35 patients (31F, 4M) with a mean age of 53.2 +/- 14.9 years and a chronic facial pain syndrome we tested the new diagnostic criteria of the International Headache Society (IHS). There was a marked female preponderance, vague description of symptoms and a long history of incorrect diagnoses. A high number of invasive procedures (3.5 +/- 3.0 (1-13)) were performed in this group. In agreement with the IHS criteria, an operation or injury to the face was a suspected cause in 43%. In contrast to the IHS criteria, our patient sample had dysaesthesiae (63%), bilateral occurrence (37%), remission periods (57%), pain attacks (23%) and superficial as well as deep pain. The IHS classification is insufficient to separate atypical facial pain from other primary headache and facial pain syndromes. We suggest a modified version of the IHS criteria for atypical facial pain.

Facial pain and muscle atrophy secondary to an intracranial tumour

Orofacial pain rarely arises from a distant site. It is unusual for orofacial pain to be associated with wasting of the facial musculature and diminished sensation. This case report describes a patient who presented with temporomandibular joint pain dysfunction syndrome which was initially successfully managed with splint therapy. She re-presented later with unilateral wasting of the muscles of mastication, facial pain and diminished sensation ipsilaterally. An intracranial meningioma was diagnosed following an extensive series of investigations.

[Hemangioma of Meckel's cavum: a case report]

A case of haemangioma of Meckel's cave is reported. The rarity of the lesion is focused, as well as its symptomatology and the radiologic changes.

Lesions in Meckel's cave: variable presentation and pathology

A series of 12 patients with mass lesions arising from Meckel's cave is presented. Patients' age on presentation ranged from 13 months to 71 years. Nine of the 12 patients had symptoms referable to the fifth cranial nerve, but only three complained of facial pain. The 12 patients presented eight different pathological entities, including meningioma, lipoma, schwannoma, malignant melanotic schwannoma, arachnoid cyst, neurofibroma, epidermoid tumor, and chordoma. Computerized tomography and magnetic resonance imaging were most useful in localizing the lesion to Meckel's cave. All 12 patients underwent a subtemporal approach to the lesion, and gross total removal was achieved in 11. Postoperative results were excellent with no increased neurological deficits seen 3 months postoperatively. Most patients had resolution of the cranial nerve deficits except for fifth nerve function, which was impaired in nine patients postoperatively. This series demonstrates that lesions in Meckel's cave can have a varied and unusual presentation, as well as an assortment of pathology. Total removal of lesions in this area resulted in relief of symptoms in most patients, with minimum morbidity.

Possibilities and limitations of microsurgery in patients with meningiomas of the sellar region

Problems associated with the operative technique and operative results in 40 patients who underwent surgical removal of a meningioma in the sellar region are analysed. Attention must be paid not only to the possibilities and limitations of microsurgery but also to general aspects such as hypothalamic and pituitary function.

Intracranial tumors in patients with facial pain

Over the past 10 years, 2000 patients with facial pain have been evaluated at the Mayfield Neurologic Institute. Sixteen of these patients were found to harbor intracranial tumors. The presenting features of this group of patients are analyzed, and the literature reviewed. Peripherally placed tumors tend to cause atypical facial pain associated with sensory loss. Middle fossa tumors may present as trigeminal neuralgia, but usually cause severe pain of an atypical nature and a progressive neurological deficit. Posterior fossa tumors are most likely to cause trigeminal neuralgia; these neoplasms are usually accompanied by subtle neurological deficits and are readily detected by current diagnostic studies.

High resolution CT of Meckel's cave

High resolution CT of the parasellar region was carried out in 50 patients studied for suspected pituitary microadenoma, but who showed normal pituitary gland or microadenoma on CT. This control group of patients all showed an ellipsoid low-density area in the posterior parasellar region. Knowledge of the gross anatomy and correlation with metrizamide cisternography suggest that the low density region represents Meckel's cave, rather than just the trigeminal ganglion alone. Though there is considerable variation in the size of Meckel's cave in different patients as well as the two sides of the same patient, the rather constant ellipsoid configuration of the cave in normal subjects will aid in diagnosing small pathological lesions, thereby obviating more invasive cisternography via the transovale or lumbar route. Patients with "idiopathic" tic douloureux do not show a Meckel's cave significantly different from the control group.

Meningiomas of Meckel's cave

Meningiomas of Meckel's cave are unusual. Forty-six cases of this tumor are described in the literature and two others are reported in this paper. Symptomatology frequently begins with typical or atypical trigeminal neuralgia; when no other signs are associated, diagnosis of the tumor is difficult. Total removal of the tumor results in a complete relief of symptoms, and no other therapy for pain is necessary.

Tumours of the fifth cranial nerve

Tumours of the fifth cranial nerve are very rare, comprising only 0.2% of all intracranial neoplasms. The authors critically review the literature, and report on 12 personal cases of trigeminal tumours (nine neurinomas, one meningioma, one epidermoid, one osteochondroma). General pathology, symptoms, and signs are analyzed, and compared with cases from the literature. Because of their insidious onset and slow "illogical" progression of misleading symptoms, trigeminal tumours often prove to be a diagnostic challenge. As a consequence they usually reach a large size before causing sufficient symptoms to lead the patient to a neurosurgical clinic. The diagnosis is therefore likely to be made by radiological investigations. The typical radiological feature (on plain skull films, pneumoencephalography, and angiography) are described, and differential diagnosis is discussed. All the patients in the present series were operated on. Surgical procedures and postoperative results are discussed.