Temporal Lobe Epilepsy Caused by Dermoid Cyst

Epilepsy surgery without lipoma removal for temporal lobe epilepsy associated with lipoma in the Sylvian fissure

Epileptic seizure is the common symptom associated with lipomas in the Sylvian fissure (Sylvian lipomas). Removal of these lipomas carries risks of hemorrhage and brain damage. We report a surgical strategy of not removing the lipoma in a case of intractable temporal lobe epilepsy associated with Sylvian lipoma. We performed anterior temporal lobectomy with preservation of the pia mater of the Sylvian fissure and achieved seizure freedom. Focal cortical dysplasia type 1 of the epileptic neocortex adjacent to the Sylvian lipoma was pathologically diagnosed. We recommend our surgical procedure in similar cases to avoid complications and achieve adequate seizure control.

Mature cystic teratoma of the temporal lobe: A rare tumor with an unusual location

Intracranial mature cystic teratoma is rare. The temporal lobe is a very unusual location and can pose a considerable diagnostic challenge. Proper histological diagnosis and long‐term follow‐up are imperative.

A Case of Dermoid Cyst Arising in the Temporal Lobe

Intracranial dermoid cysts are rare congenital lesions that result from abnormal sequestration of ectodermal cells during neural tube formation. These tumors are especially rare in lateral areas such as in the temporal lobe. In this study, we report a case of dermoid cyst located in the right temporal lobe. A 50-year-old man was referred for further treatment of a tumor. CT revealed a low-density mass lesion in the right temporal lobe, with calcification. MRI showed the lesion with high signal intensity on diffusion-weighted imaging, high-low mixed signal intensity on T1-weighted imaging, and iso-high signal mixed intensity on T2-weighted imaging; the capsule was enhanced with gadolinium. Differential diagnosis included dermoid cyst, epidermoid cyst, teratoma, and neurenteric cyst. We decided to perform surgery for the improvement of his symptom, histopathological diagnosis, and radical cure. A right temporal craniotomy was performed, and the tumor was found adherent to the surrounding brain tissue. The tumor was completely removed under subpial dissection. Hair was confirmed in the tumor content. On histopathology, the cyst wall was lined with stratified squamous epithelium, sebaceous glands, small vessel aggregates, and inflammatory infiltrate. Keratinized material and hair were found in the lumen. The patient was discharged 7 days after surgery with no new neurologic deficits. This case was unusual in terms of the effect of gadolinium enhancement on MRI, and the presence of adipose tissue and calcification were useful for diagnosis. It is vital to consider prevention of chemical meningitis due to intrathecal dissemination of the tumor content intraoperatively.

Non-Ruptured Temporal Lobe Dermoid Cyst Concomitant with Focal Cortical Dysplasia Causing Temporal Lobe Epilepsy-A Case Report and Literature Review

Background: Intracranial dermoid cyst is a rare, benign, nonneoplastic tumor-like lesion that could cause seizures, headache, and hydrocephalus. We hypothesized that the temporal lobe dermoid cyst in combination with other factors were causing the epileptic seizure. Methods: We encountered a 17-year-old girl with anti-seizure medication-resistant epilepsy secondary to dermoid cyst located in the temporal region depicted on magnetic resonance imaging (MRI). She showed neither symptoms of meningitis nor rupture of the cyst according to serial MRI. We hypothesized that temporal lobe dermoid cyst in combination with other factors, such as focal cortical dysplasia (FCD), etc., was causing epileptic seizures in this case. She underwent dermoid cyst removal surgery with resection of the tip of the antero-inferior temporal lobe. Results: Histopathological study showed multiple small intramedullary dermoid cysts in the left antero-inferior temporal lobe in addition to MRI lesions and FCD. Conclusion: A patient with medically intractable epilepsy secondary to left temporal lobe dermoid cyst showed multiple intramedullary dermoid cysts and focal cortical dysplasia that might have interacted to create epileptogenicity. To our knowledge, this is the first case report of dermoid cyst concomitant with FCD.

Focal traumatic rupture of a dermoid cyst in a pediatric patient: case report and literature review

BACKGROUND

Dermoid cysts are rare congenital teratomas that can occasionally rupture and cause chemical meningitis, neurological deficit, or hydrocephalus. Rarely, dermoid cysts in the pediatric population can rupture spontaneously and even more rarely rupture due to trauma. To date, there are only five documented cases of traumatic rupture of a dermoid cyst. A 2-year-old male presented with 5 days of left eye ptosis and ophthalmoplegia after suffering a fall and was found to have a ruptured left anterior clinoid dermoid cyst that was surgically resected. The patient had significant improvement postoperatively.

SIGNIFICANCE

To the authors' knowledge, this is the first reported case in the literature of a ruptured dermoid cyst after trauma in a pediatric patient and the first case of a traumatically ruptured dermoid cyst presenting with neurological deficit.

Seizure freedom from temporal lobe epilepsy with mesial temporal lobe tumor by tumor removal alone without hippocampectomy despite remaining abnormal discharges on intraoperative electrocorticography: Report of two pediatric cases and reconsideration of the surgical strategy

Background:

In the surgical treatment of temporal lobe epilepsy with mesial temporal lobe tumor, whether to remove the hippocampus aiming for a better seizure outcome in addition to removing the tumor is a dilemma. Two pediatric cases treated successfully with tumor removal alone are presented.

Case Description:

The first case was an 11-year-old girl with a ganglioglioma in the left uncus, and the second case was a 9-year-old girl with a pleomorphic xanthoastrocytoma in the left parahippocampal gyrus. In both cases, the hippocampus was not invaded, merely compressed by the tumor. Tumor removal was performed under intraoperative electrocorticography (ECoG) monitoring. After tumor removal, abnormal discharges remained at the hippocampus and adjacent temporal cortices, but further surgical interventions were not performed. The seizures disappeared completely in both cases.

Conclusions:

When we must decide whether to remove the hippocampus, the side of the lesion, the severity and chronicity of the seizures, and the presence of invasion to the hippocampus are the factors that should be considered. Abnormal discharges on ECoG at the hippocampus or adjacent cortices are one of the factors related to epileptogenicity, but it is simply a result of interictal irritation, and it is not an absolute indication for additional surgical intervention.

Endoscopic Transnasal Transpterygoid Excision of an Infratemporal Dermoid Cyst

OBJECTIVE

Intracranial dermoid cysts are rare, slow-growing masses of sellar, parasellar regions, and posterior cranial fossa. The symptomatology of these cysts depends on the localization and presence of rupture. The preoperative diagnosis of these cysts by imagining techniques is distinctive as they have characteristic appearances.

PATIENT

Endoscopic transnasal transpterygoid approach to infratemporal fossa for an extradural dermoid cyst of a 24 year-old woman is presented in this clinical report. Headache, dizziness, and retro orbital pain were her main complaints and diagnostic imagining studies designated an intracranial dermoid cyst preoperatively. The cyst was excised uneventfully with no recurrence 6 months after the operation.

CONCLUSION

Surgery of intracranial lesions neighboring critical vital neurovascular structures can be challenging to the surgeon. Alternative minimal invasive approaches should always be considered for averting life-threatening complications.

Insular and Sylvian Fissure Dermoid Cyst with Giant Cell Reactivity: Case Report and Review of Literature

BACKGROUND

Dermoid cysts are rare intracranial tumors that are most commonly found infratentorially and along the midline. Characterized by slow growth and often found incidentally, these lesions can nonetheless have severe complications, notably rupture leading to chemical meningitis. They infrequently present as a supratentorial and lateralized mass. As such, sylvian fissure dermoid cysts are exquisitely rare. We present a rare case of a dermoid cyst with giant cell reactivity suggestive of focal rupture and chronic inflammation.

CASE DESCRIPTION

A 61-year-old female presented with new-onset seizures. Magnetic resonance imaging revealed a right insular mass measuring 4.3 × 4.5 cm with compression of the ipsilateral frontal and temporal lobes. The mass was nonenhancing; however, it was bright on diffusion-weighted imaging, suggesting a dermoid cyst. She underwent craniotomy for tumor resection. Histologic analysis revealed keratinizing squamous epithelium, sebaceous glands, and hair follicles associated with giant cell reaction involving the capsule of the cyst consisted with dermoid cyst. At 2.5 years post operation, she is seizure free and without evidence of recurrence.

CONCLUSION

The dermoid cyst in our patient was not grossly ruptured, but histopathologic analysis revealed giant cell reactivity, which may indicate focal rupture or chronic inflammation. The relationship between rupture of dermoid cysts and inflammation is not well elucidated. It is not known whether symptoms occur immediately after rupture or as an acute manifestation of a chronic process following rupture. As these lesions are quite rare and rupture is even rarer, more diligence on our part regarding details of histopathology for dermoid cysts is necessary.

Long-term outcome and neuroradiologic changes after multiple hippocampal transection combined with multiple subpial transection or lesionectomy for temporal lobe epilepsy

OBJECTIVE

Multiple hippocampal transection (MHT) is a surgical procedure developed to avoid postoperative memory decline. Its efficacy has been documented in only a few small series with relatively short observation periods. We prospectively evaluated the long-term seizure and cognitive outcomes of MHT combined with multiple subpial transection or lesionectomy (MHT + MST/L). Moreover, we quantitatively evaluated the structural and metabolic neuroradiologic changes after the procedure to elucidate the anatomofunctional correlates of memory preservation.

METHODS

Twenty-four patients underwent MHT + MST/L for treatment of drug-resistant mesial temporal lobe epilepsy (mTLE) and were followed for more than 5 years. Indications for the procedure were the following: (1) verbally dominant-sided surgery in patients with a radiologically normal hippocampus or normal/near normal memory, and (2) surgery for patients with concomitant epileptic activity on the contralateral side, that is, when the surgery was considered a high risk for severe postoperative memory decline. Seizure outcome was evaluated using Engel's classification 1, 2, and 3 years after surgery, and at the last visit (LV). Three subgroups were evaluated as well: magnetic resonance imaging (MRI) negative (MN), hippocampal sclerosis (HS), and normal hippocampus with extrahippocampal lesion (NHEL). The long-term cognitive outcome was followed through to LV in patients who underwent verbally dominant-sided surgery. Hippocampal volume (HV), diffusion tensor parameters (DTP), and glucose utilization (GU) were determined from MRI and fluorodeoxyglucose-positron emission tomography (FDG-PET) studies performed before and >6 months after surgery.

RESULTS

Whereas the rate of Engel class I as a whole was 71% at 1 year and 67% at LV, the rates in the MN, HS, and NHEL groups were 60%, 67%, and 100% at 1 year, respectively, and 70%, 56%, and 80% at LV, respectively. Memory indices after verbally dominant-sided surgery transiently declined at 1 month but recovered to and remained at the preoperative level through LV. The HV, DTP of the fornix, and GU of the temporal lobe on the treated side showed pathologic changes even when the transiently declined memory indices had recovered to the preoperative level.

SIGNIFICANCE

The long-term outcome for complex partial seizures after MHT + MST/L was comparable to that seen after anterior temporal lobectomy. The long-term cognitive outcome was favorable, even for patients with a high risk of severe postoperative memory decline. MHT + MST/L may be a treatment option for mTLE in which resective surgery carries a risk of postoperative memory decline, particularly in patients without MRI lesion. A discrepancy between the preserved memory and the pathologic neuroradiologic changes indicates the necessity for further studies including functional MRI.

Giant middle fossa epidermoid presenting as holmes' tremor syndrome

Intracranial dermoids may gradually reach an enormous size before the onset of symptoms. Common clinical presentations of intracranial epidermoid include headache and seizures. We present a case of a 35-year female patient with giant middle fossa epidermoid that presented with Holmes’ tremor syndrome, and we review the relevant literature. To the best of our knowledge, such a presentation has not previously been described in the literature.

Transsylvian hippocampal transection for mesial temporal lobe epilepsy: surgical indications, procedure, and postoperative seizure and memory outcomes

Object

Amygdalohippocampectomy is a well-established, standard surgery for medically intractable mesial temporal lobe epilepsy (MTLE). However, in the case of MTLE without hippocampal atrophy or sclerosis, amygdalohippocampectomy is associated with decreased postoperative memory function. Hippocampal transection (HT) has been developed to overcome this problem. In HT the hippocampus is not removed; rather, the longitudinal hippocampal circuits of epileptic activities are disrupted by transection of the pyramidal layer of the hippocampus. The present study describes a less invasive modification of HT (transsylvian HT) and presents the seizure and memory outcomes for this procedure.

Methods

Thirty-seven patients with MTLE (18 men and 19 women; age range 9–63 years; 19 with surgery on the right side and 18 with surgery on the left side; seizure onset from 3 to 34 years) who were treated with transsylvian HT were retrospectively analyzed. All patients had left-side language dominance, and follow-up periods ranged from 12 to 94 months (median 49 months). Seizure outcomes were evaluated for all patients by using the Engel classification. Memory function was evaluated for 22 patients based on 3 indices (verbal memory, nonverbal memory, and delayed recall), with those scores obtained using the Wechsler Memory Scale–Revised. Patients underwent evaluation of the memory function before and after surgery (6 months–1 year).

Results

Engel Class I (completely seizure free) was achieved in 25 patients (67.6%). Class II and Class III designation was achieved in 10 (27%) and 2 patients (5.4%), respectively. There were differences in memory outcome between the sides of operation. On the right side, verbal memory significantly increased postoperatively (p = 0.003) but nonverbal memory and delayed recall showed no significant change after the operation (p = 0.718 and p = 0.210, respectively). On the left side, all 3 indices (verbal memory, nonverbal memory, and delayed recall) showed no significant change (p = 0.331, p = 0.458, and p = 0.366, respectively).

Conclusions

Favorable seizure outcome and preservation of verbal memory were achieved with transsylvian HT for the treatment of MTLE without hippocampal atrophy or sclerosis.

Mature cystic teratoma (dermoid cyst) in the sylvian fissure: a case report and review of the literature

Mature cystic teratoma (dermoid cyst) inside the Sylvian fissure is rare. A 14-year-old boy presented with 2 episodes of generalized tonic-clonic seizures. Using a fat-suppressed, T1-weighted sequence, magnetic resonance imaging revealed a hypointense nonenhancing mass in the left Sylvian fissure. He underwent left pterional craniotomy for total tumor resection. The pathological diagnosis was mature cystic teratoma (dermoid cyst). Headache and seizures are the leading symptoms. Cyst rupture causes inflammation of cholesterol crystals, and the cyst contents may cause seizure. Surgical resection is the treatment of choice, but radical resection is not advised if critical neurovascular structure can be injured.

Epidermoid cyst involving the medial temporal lobe: surgical pathologic features of the epileptogenic lesion

Epidermoid cysts in the middle fossa are rare and may involve the temporal lobe and lateral ventricle. Affected patients often suffer from seizures, but the pathomechanisms underlying the epileptogenic lesions have remained unclear. Here we report the surgical pathological features of the hippocampus in a 31-year-old woman with mesial temporal lobe epilepsy (mTLE), in whom an epidermoid cyst involving the right basal cistern and inferior horn of the lateral ventricle was evident. The ictal electrocorticogram indicated seizure onset at the parahippocampal gyrus. An anterior temporal lobectomy and amygdalohippocampectomy were performed. Histologically, the hippocampus showed marked atrophy with severe loss of pyramidal neurons in the cornu Ammonis subfields and granule cell loss in the dentate gyrus. At the ventricular surface of the hippocampus, there were small granulomatous lesions with spicularly anchored keratin substance. These features indicated multiple and chronic stab wounds by the cyst contents and consequent local inflammatory responses within the parenchyma. The predisposition to adhesion between the tumor and hippocampus may have caused neurons to develop abnormal irritability to certain chemical mediators present in the cyst. Epileptogenicity involving the atrophic hippocampus and medial temporal lobes nearby may have developed in association with these processes. This case appears to provide information that is useful for surgical planning in patients with mTLE and epidermoid cysts involving the medial temporal lobe.

Sylvian cistern dermoid cyst presenting with dysgeusia

It is rare for a patient with a dermoid cyst (DC) to present with taste dysfunction. A 58-year-old man presented with an altered sense of taste. Magnetic resonance imaging of the brain showed a mass lesion in the right insula with compression effect. The tumour was resected and was found to be a DC. The postoperative course was uneventful, and the patient resumed his usual taste sensation within the early postoperative period. To the best of our knowledge, this is the first report of a sylvian cistern DC that presented with dysgeusia.

Neuropsychological profiling of ischemic deficit secondary to ruptured dermoid cyst: a case report

This report presents a case of a 39-year-old male with a spontaneously ruptured frontotemporal dermoid cyst. Intraoperatively, during surgical resection of the cyst, significant fat spillage occurred associated with a profound anterior circulation vasospasm. The patient underwent serial neuropsychological evaluation over five months, revealing a profile of initial deterioration, followed by delayed recovery of cognitive function. A review of the literature reveals three other case reports describing ischemic deficit after dermoid rupture, but the cognitive impairment associated with this pathology has never been formally profiled before, and it may be possible to draw analogies to the well-established ischemic deficit post-subarachnoid hemorrhage found in the literature. Neuropsychological profiling additionally informs us about the nature and progression of this entity from a cognitive perspective and whether the etiology of deficit caused by dermoid rupture could be localized, or global, secondary to diffuse fatty dissemination in the CSF.