Multiple epidermoid cysts located in the pineal and extracranial regions treated by neuroendoscopy

Shear wave elastography for intracranial epidermoid tumors

BACKGROUND

Ultrasound elastography (USE) is a novel technique that assesses the mechanical properties of body tissues in real time. Based on elasticity measurements, USE enables the differentiation of tumor tissue from surrounding normal tissue.

OBJECTIVES

We aimed to evaluate an intraoperative SWE technique for differentiating tumor tissue (epidermoid cyst) from the surrounding normal brain tissue based on elastic properties.

METHODS

We prospectively report the intraoperative elasticity assessments of four patients diagnosed with epidermoid cysts. Along with standard ultrasonography, intraoperative shear wave elastography (SWE) was used to identify tumor tissue and assess the elasticity of each tumor and the surrounding normal brain.

RESULTS

USE enabled the differentiation between epidermoid cysts and the surrounding normal brain tissue in real time intraoperatively; visual data (SWE elasticity map) and quantitative data (elasticity measurements in kilopascals) were utilized to identify the epidermoid cyst based on its elastic properties. The area representing the epidermoid cyst had an increased elasticity on SWE view and high mean elasticity values (193.7 ± 70.9 kPa in case 1, 168 ± 24.5 kPa in case 2, 205.1 ± 6.7 kPa in case 3, and 101.3 ± 12.6 kPa in case 4). The area representing the adjacent normal brain tissue on SWE view had lower mean elasticity values (14.9 ± 1.9 kPa in case 1, 22.6 ± 8.3 kPa in case 2, and 23.8 ± 1.4 kPa in case 4).

CONCLUSION

This study demonstrates the feasibility and promising value of SWE as an intraoperative tool during epidermoid cyst resection. Epidermoid tissue remnants that are hidden from the microscopic view can be detected using SWE.

Surgical Resection of Pineal Epidermoid Cyst Contributed to Relieving Schizophrenia Symptoms

BACKGROUND

The pineal gland has been demonstrated to be involved in the development of mood and psychotic disorders. However, few studies have looked at the relationship between pineal region tumors and psychiatric disorders. Intracranial epidermoid cysts usually arise in the cerebellopontine angle area and are extremely rare in the pineal region. The case of pineal epidermoid cyst presenting as schizophrenia has never been reported before.

CASE PRESENTATION

We described the case of a 23-year-old man who presented to the hospital with symptoms suggestive of schizophrenia. During work-up, he was found to have a pineal lesion on brain magnetic resonance imaging. Total resection of the tumor was subsequently performed, and pathology confirmed an epidermoid cyst. One month after surgery, the patient's psychotic symptoms significantly improved free of drug and fully returned to work 3 months postoperatively.

CONCLUSIONS

This case highlights the importance of including mass lesions of the pineal region in the differential diagnosis of psychotic disorders. It also provides further support that the pineal region may play a role in the pathophysiology of psychiatric diseases, although more studies will be needed to elucidate this interesting connection.

Primary Intracranial Epidermoid Carcinoma with Diffuse Leptomeningeal Carcinomatosis: Report of Two Cases

BACKGROUND

Malignant degeneration of epidermoid cyst (EC) with accompanying leptomeningeal carcinomatosis (LC) at presentation is extremely rare. We add two cases to the literature, including the first case of primary brainstem involvement with simultaneous diffuse LC, and discuss clinical and radiological cues to differentiate benign and malignant epidermoid tumors for early diagnosis.

CASE DESCRIPTION

The first patient in this report was a 54-year-old woman with recurrent aseptic meningitis and hydrocephalus. Imaging revealed a prepontine and parapontine extra-axial EC with an intra-axial brainstem ring-enhancing cystic lesion, diffuse leptomeningeal enhancement, and intradural extramedullary nodular deposits throughout the spine. Surgical decompression of the cysts confirmed the diagnosis of invasive primary squamous cell carcinoma of the brainstem and benign epidermoid tumor of the cerebellopontine cistern. The second patient was a 37-year-old woman with extensive left-sided cranial neuropathies. Imaging revealed prepontine and parapontine enhancing and nonenhancing deposits along multiple cranial nerves and diffuse leptomeningeal nodular enhancement in the thoracolumbar spine. A biopsy confirmed the diagnosis of infiltrative, poorly differentiated carcinoma adjacent to a benign EC. Both patients underwent systemic screening to rule out metastatic disease.

CONCLUSIONS

These cases illustrate that a high index of clinical suspicion is necessary for early diagnosis of disseminated disease in cases of recurrent episodes of aseptic meningitis. In cases of primary benign EC, aggressive resection should be attempted to reduce the risk of malignant degeneration. A separate biopsy specimen from the enhancing portion of the tumor is used to rule out an underlying coexisting malignancy. Multimodal management carries the best prognosis for primary intracranial squamous cell carcinoma with LC.

Atypical intracranial epidermoid cysts: rare anomalies with unique radiological features

Epidermoid cysts are benign slow growing extra-axial tumours that insinuate between brain structures, while their occurrences in intra-axial or intradiploic locations are exceptionally rare. We present the clinical, imaging, and pathological findings in two patients with atypical epidermoid cysts. CT and MRI findings for the first case revealed an intraparenchymal epidermoid cyst that demonstrated no restricted diffusion. The second case demonstrated an aggressive epidermoid cyst that invaded into the intradiploic spaces, transverse sinus, and the calvarium. The timing of ectodermal tissue sequestration during fetal development may account for the occurrence of atypical epidermoid cysts.

An analysis of intracranial epidermoid tumors with malignant transformation: treatment and outcomes

OBJECTIVE

While typically benign, epidermoid tumors upon rare occasion can undergo malignant transformation, which carries a poor prognosis. Here, we reviewed treatment strategies and analyzed outcomes for every case of malignant epidermoid tumor reported since its original description in 1912.

METHODS

A comprehensive literature review identified all reported cases of malignant transformation of intracranial epidermoid tumor. Treatments were categorized as follows: palliative management, stereotactic radiosurgery (SRS), chemotherapy, and surgery plus multiple (2+) adjuvant therapies. Survival data of these groups were compared to treatment outcomes for patients receiving only surgical resection, as reported in our previous study.

RESULTS

We identified 58 cases of intracranial epidermoid tumor with malignant degeneration. Average survival regardless of therapy was 11.8 months. Mean survival outcomes for groups treated with palliative management, chemotherapy, SRS, and multiple postoperative adjuvant therapies were 5.3 months, 25.7 months, 29.2 months, and 36.3 months, respectively. Outcomes for the groups including SRS, chemotherapy, and multiple post-operative adjuvant therapies were statistically significant compared to surgical resection alone.

CONCLUSION

While there remains a lack of consensus regarding the best approach to the management of patients with malignant epidermoid tumors, our systematic analysis characterizes and confirms the added benefit of SRS, chemotherapy, and multimodal adjuvant therapies.

Clinical characteristics and diagnostic imaging of epidermoid tumors

Epidermoid tumors are rare, benign congenital lesions which typically present between the third and fifth decades of life. They are thought to originate from ectodermal cells misplaced during neural tube formation and separation. While epidermoids may present anywhere in the cranial vault, they are characteristically located intradurally and in a paramedian position within the cerebellopontine angle and parasellar regions. Although imaging results may vary depending upon cystic content, CT scanning generally reveals a well-circumscribed, nonenhancing, lobulated, hypodense mass. They are hypointense on T1-weighted MRI, and hyperintense on T2-weighted MRI, diffusion-weighted imaging and fluid-attenuated inversion recovery sequences. The use of appropriate neuroimaging should be utilized to differentiate epidermoids from other intracranial lesions. While gross total resection of these tumors is the definitive treatment to prevent recurrence and aseptic meningitis, a subtotal resection may be necessary to preserve neurological function.

A Review of Neuroendoscopy and Potential Applications in Veterinary Medicine

The endoscope was first developed over 200 yr ago. Endoscopy has since been applied to many disciplines of medicine. Its application to the nervous system was initially slow and not widely accepted and mainly involved the biopsy of tumors and the treatment of hydrocephalus. Several reasons for neuroendoscopy's limited use include inadequate endoscope technology, high skill level required, the advent of the surgical microscope, and the development of other treatments such as ventricular shunting. Over the past 50 yr, improvements in optical glass lenses, fiber optics, and electrical circuitry has led to better equipment and a revival of neuroendoscopy. Neuroendoscopy is now used in many diseases in human medicine including hydrocephalus, neoplasia, and intracranial cysts. This review presents the history of neuroendoscopy, the equipment and technology used, and the possible translation of techniques currently used in human medicine to veterinary medicine.

Endoscopic supracerebellar infratentorial approach for pineal cyst resection: technical case report

OBJECTIVE

Accepted surgical strategies to address symptomatic pineal cysts include transventricular flexible or rigid endoscopy and supracerebellar infratentorial or occipital transtentorial microsurgical approaches. We report the first application of the endoscopic supracerebellar infratentorial approach for the complete resection of a pineal cyst. Unlike transventricular endoscopy, this technique poses no risk to the fornices and can be applied independent of ventricular size.

CLINICAL PRESENTATION

A 37-year-old woman sought treatment for intractable headaches. A thorough evaluation revealed only a pineal cyst exerting mass effect on the tectum but causing no hydrocephalus. A period of nonoperative management was unsuccessful, and the patient was referred for surgery.

TECHNIQUE

The patient was positioned in the semi-sitting position. The supracerebellar infratentorial corridor was accessed through a burr-hole. The pineal cyst was resected completely via the endoscope. Postoperatively, the patient's headaches resolved completely.

CONCLUSION

The endoscopic supracerebellar infratentorial approach involves minimal brain retraction, poses no risk to the fornices, allows visualization and avoidance of the Galenic veins, and can be performed regardless of the size of the ventricle. Consequently, it is an excellent minimally invasive surgical option for resection or fenestration of symptomatic pineal cysts.

Endoscope-Controlled Microneurosurgery to Treat Middle Fossa Epidermoid Cysts: Technical Case Report

Objective:

To present an alternative technique of endoscope-controlled microneurosurgery for the treatment of middle fossa epidermoid cysts.

Methods:

The three operations described were performed through an approximately 2-cm diameter temporal craniotomy after a straight skin incision was made. Resection was then performed under the magnification of a 30-degree rigid endoscope, which mandated the use of exclusively conventional microsurgical instruments.

Results:

Total resection was accomplished in all three patients with large middle fossa epidermoid cysts through a small temporal corticectomy, without damage to neurovascular structures.

Conclusion:

This procedure allowed the association of a smaller craniotomy, better cosmetic results, and minor retraction of the brain to wide resection of the tumor and satisfactory functional outcomes.