Endoscopic endonasal approach for resection of ventral skull base keratinaceous cysts

Intrasellar Dermoid Cyst: Case Report of a Rare Lesion and Systematic Literature Review Comparing Intrasellar, Suprasellar, and Parasellar Locations

OBJECTIVE

Intracranial dermoid cyst (DC) is a rare benign, slow-growing lesion, most commonly arising along the midline. They can occur in the supratentorial compartment, very rarely involve the sellar region and only exceptionally are intrasellar. The aim of our study is to address the challenges in the diagnosis and management of sellar DCs.

METHODS

We performed a systematic review of sellar DCs, in keeping with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, and described an intrasellar DC in a 32-year-old female who presented with bilateral blurring vision.

RESULTS

The review identified 4 intrasellar, 29 suprasellar, and 28 parasellar cases. Intrasellar DCs more likely present with progressive visual impairment and pituitary hormone dysfunctions during the fifth decade of life. Suprasellar and parasellar DCs are typically diagnosed during the third decade of life because of diplopia, ptosis, trigeminal hypoaesthesia/para-esthesia or cyst's rupture. Sellar DCs are typically hypodense on computed tomography scans and contain calcifications. Magnetic resonance imaging features include T1 hyperintensity, T2 heterogeneous intensity, no restriction on diffusion-weighted images, and no contrast enhancement. Surgery is the treatment of choice. Gross total resection is achieved in 60% of intrasellar and 61.9% of suprasellar and parasellar DCs. Early postoperative complications are reported in 40.0%, 16.7%, and 23.8% of intrasellar, suprasellar, and parasellar DCs, respectively.

CONCLUSIONS

Intrasellar DCs are rare lesions typically diagnosed later than suprasellar and parasellar DCs due to their different clinical presentations. However, they should be considered in the differential diagnosis of cystic lesions of the sella, including epidermoid cysts, craniopharyngiomas, Rathke's cleft cysts, and teratomas.

Endoscopically operated 15 ventral skull-base dermoid and epidermoid cysts: Outcomes of a case series and technical note

BACKGROUND

Epidermoid and dermoid tumors in the sellar region are rare. These cystic lesions are a surgical challenge, as the thin capsule adheres firmly to nearby structures. A case series of 15 patients is presented.

METHODS

The patients were operated on in our clinic between April 2009 and November 2021. The endoscopic transnasal approach (ETA) was used. Lesions were located in the ventral skull base. In addition, the literature was reviewed to compare clinical features and outcomes of ventral skull-base epidermoid/dermoid tumors operated on via ETA.

RESULTS

In our series, removal of cystic contents and tumor capsule (gross total resection: GTR) was achieved in 3 patients (20%). GTR was not possible for the others, because of adhesions to vital structures. Near total resection (NTR) was achieved in 11 patients (73.4%), and subtotal resection (STR) in 1 (6.6%). At a mean follow-up of 55±26.27 months, there were no cases of recurrence requiring surgery.

CONCLUSION

Our series demonstrates that ETA is suitable for resection of epidermoid and dermoid cysts in the ventral skull base. GTR cannot always be the absolute clinical aim, because of inherent risks. In patients with expected long-term survival, the aggressiveness of surgery should be weighed on an individual risk/benefit basis.

The Fate of Fat Graft in Extended Endoscopic Transtuberculum-Transplanum Approaches

OBJECTIVE

To analyze the long-term fate of autologous fat graft in skull base reconstruction after an extended endoscopic transtuberculum-transplanum approach.

METHODS

Data from 98 consecutive patients undergoing a transtuberculum-transplanum approach and skull base reconstruction using the 3F technique between June 2017 and January 2022 were retrospectively analyzed. Fat graft volume was measured on postoperative day 1 computed tomography scan and early (≤15 days), 3-month, and 1-year magnetic resonance imaging scans. Fat graft volumes and resorption rate were calculated in patients with a complete radiological follow-up and correlated to demographic, pathological, and surgical features.

RESULTS

Fat volumes and resorption rate were calculated in 55 patients. Mean volume of fat on postoperative day 1 computed tomography scan was 3.58 ± 1.89 cm3 and on early, 3-month, and 1-year postoperative magnetic resonance imaging scans was 2.45 ± 1.57 cm3, 1.40 ± 0.76 cm3, and 0.92 ± 0.56 cm3, respectively. Resorption rate was 44% after 3 months and 67% after 1 year. Resorption rate did not significantly correlate with demographic, pathological, and surgical features. Cerebrospinal fluid leak requiring redo surgery occurred in 1 patient (1/98, 1.2%). There were 6 cases of visual worsening (6/98, 6.1%); no cases correlated to fat overpacking. No delayed complications at the donor site or at the grafting site were noted.

CONCLUSIONS

Autologous fat graft in skull base reconstruction is observed to shrink significantly over time, reaching 67% in 1 year. Its use is associated with excellent outcomes, making it a favored material for skull base reconstruction.

Endoscopic Endonasal Resection of Meckel's Cave Epidermoid Cysts: Case Discussion and Literature Review

Meckel's cave (MC) epidermoid cysts are relatively uncommon lesions. In cases where surgical excision is indicated, resection is often carried out via a frontosphenotemporal craniotomy from an anterolateral approach or a temporal craniotomy with or without a petrosectomy for a lateral corridor; both of these routes are associated with brain retraction and potential neurovascular injury. The anterior location of MC in the middle cranial fossa makes safe access via posterior fossa-based approaches—such as the retrosigmoid approach—challenging as well. Here, we present the cases of two patients diagnosed with epidermoid cysts in MC who underwent surgical resection via an endoscopic endonasal transpterygoid approach. Near-total resection was achieved in both cases, with only mild transient neurologic disturbances postoperatively. Radiographically, no evidence of residual disease was noted in either patient. We further review the nuances of an extended endoscopic endonasal approach to these lesions.

Intradiploic Epidermoid of the Tegmen Tympani With Cochlear Invasion

Intradiploic epidermoid cysts are benign tumors that account for ∼1% of all intracranial space occupying lesions. Because of the indolent growth, symptoms are usually gradual in onset with a prolonged duration. While they can originate from any part of the skull, temporal bone epidermoids are rare. We describe a case of an unusual presentation of a temporal bone epidermoid cyst. A 64-year-old male presented with sudden right-sided hearing loss and worsening right eyelid ptosis was found to have a nonenhancing lobulated mass above the right tegmen tympani with complex signal and possible communication with the apical turn of the cochlea on magnetic resonance imaging (MRI). He underwent subtemporal craniotomy with excision of the cyst lining and matrix without any complications and was discharged home on postoperative day 1. Complete excision was not possible given that the facial nerve and cochlea were improved. He had subjective improvement in his hearing immediately after surgery. Intradiploic epidermoid cysts are benign tumors that can present anywhere in the skull with variable presentation. While complete excision is the goal, neurovascular involvement may make this challenging. The use of computed tomography scan and MRI can prove to be invaluable in determining accurate diagnosis and size for surgical planning.

Endoscopic endonasal resection of epidermoid cysts involving the ventral cranial base

OBJECTIVE

Epidermoid cysts (ECs) commonly extend to involve the ventral cisterns of the cranial base. When present, symptoms arise due to progressive mass effect on the brainstem and adjacent cranial nerves. Historically, a variety of open microsurgical approaches have been used for resection of ECs in this intricate region. In recent years, the endoscopic endonasal approach (EEA) has been proposed as an alternative corridor that avoids crossing the plane of the cranial nerves. To date, there is a paucity of data in the literature regarding the safety and efficacy of the EEA in the treatment of ECs of the ventral cranial base.

METHODS

The authors reviewed a prospectively acquired database of EEAs for resection of ECs over 8 years at Weill Cornell, NewYork-Presbyterian Hospital. All procedures were performed by the senior authors. Standardized clinical and radiological parameters were assessed before and after surgery. Statistical tests were used to determine the impact of previous surgery and tumor volume on extent of resection and recurrence as well as the method of closure on rate of CSF leak.

RESULTS

Between January 2009 and February 2017, 7 patients (4 males and 3 females; age range 16-70 years) underwent a total of 8 surgeries for EC resection utilizing the EEA. Transplanum and transclival extensions were performed in 3 and 5 patients, respectively. Methods of closure incorporated a gasket seal in 6 of 8 procedures and a nasoseptal flap in 7 of 8 procedures. Gross-total resection (GTR) was achieved in 43% of patients, and near-total resection (> 95%) was obtained in another 43%. Complications included diabetes insipidus (n = 2), postoperative CSF leak (n = 2), transient third cranial nerve palsy (n = 1), and epistaxis (n = 1). With a mean follow-up of 43.5 months, recurrence has been observed in 2 of 7 patients. In 1 case, reoperation for recurrence was required 71 months following the initial surgery. Use of the gasket-seal technique with nasoseptal flap coverage significantly correlated with the absence of postoperative CSF leakage (p = 0.018). GTR was achieved in 25% of the patients who had prior surgeries and in 50% of patients without previous resections. The mean volume of cysts in which GTR was achieved (4.3 ± 1.8 cm3) was smaller than that in which subtotal or near-total resection was achieved (12.2 ± 11 cm3, p = 0.134).

CONCLUSIONS

The EEA for resection of ECs of the ventral cranial base is a safe and effective operative strategy that avoids crossing the plane of the cranial nerves. In the authors' experience, gasket-seal closure with nasoseptal flap coverage has been associated with a decreased risk of postoperative CSF leakage.

Endoscopic endonasal surgery for epidermoid and dermoid cysts: a 10-year experience

OBJECTIVE

Epidermoid and dermoid cysts may be found along the cranial base and are commonly resected via open transcranial approaches. The use of endoscopic endonasal approaches for resection of these tumors has been rarely reported.

METHODS

The authors retrospectively reviewed the medical records of 21 patients who underwent endoscopic endonasal surgery for epidermoid and dermoid cyst resection at the University of Pittsburgh Medical Center between January 2005 and June 2014. Surgical outcomes and variables that might affect the extent of resection and complications were analyzed.

RESULTS

Total resection (total removal of cyst contents and capsule) was achieved in 8 patients (38.1%), near-total resection (total removal of cyst contents, incomplete removal of cyst capsule) in 9 patients (42.9%), and subtotal resection (incomplete removal of cyst contents and capsule) in 4 patients (19%). Larger cyst volume (≥ 3 cm3) and intradural location (15 cysts) were significantly associated with nontotal resection (p = 0.008 and 0.0005, respectively). In the whole series, surgical complications were seen in 6 patients (28.6%). No complications were observed in patients with extradural cysts. Among the 15 patients with intradural cysts, the most common surgical complication was postoperative CSF leak (5 patients, 33.3%), followed by postoperative intracranial infection (4 patients, 26.7%). Larger cysts and postoperative CSF leak were associated with intracranial infection (p = 0.012 and 0.028, respectively). Subtotal resection was marginally associated with intracranial infection when compared with total resection (p = 0.091). All patients with neurological symptoms improved postoperatively with the exception of 1 patient with unchanged abducens nerve palsy.

CONCLUSIONS

Endoscopic endonasal approaches may be effectively used for resection of epidermoid and dermoid cysts in carefully selected cases. These approaches are recommended for cases in which a total or near-total resection is possible in addition to a multilayer cranial base reconstruction with vascularized tissue to minimize the risk of intracranial infection.

Suprasellar keratinous cyst: A case report and review on its radiological features and treatment outcome

BACKGROUND

Keratinous or epidermoid cysts (ECs) are encapsulated lesions lined by squamous cell epithelium. They comprise approximately 1% of intracranial lesions. Contrary to dermoid cysts, they lack dermal elements such as sebaceous or apocrine glands and hair follicles. The sellar region is the second most common intracranial site following the cerebellopontine angle. Here, we report a case of EC in a patient who complained of endocrine disturbances. We also performed a systematic review on previously published cases to analyze clinical and radiological characteristics and report the treatment outcomes of suprasellar ECs.

CASE DESCRIPTION

A 42-year-old woman presented with a one-year history of amenorrhea, weight gain, severe headache, and visual disturbances for 6 months. Work-up identified an elevated prolactin level and a temporal field defect of the right eye. Magnetic resonance imaging (MRI) showed a cystic suprasellar lesion pushing on the optic chiasm. She underwent endoscopic trans-sphenoidal surgery, which confirmed a keratinous cyst on histology. Postoperatively, complete resection was confirmed on imaging. She did well although her hospital stay was prolonged due to diabetes insipidus and hypocortisolism.

CONCLUSION

Chronic endocrine disturbances can be the presenting complaints of a suprasellar EC, whose T1-weighted MRI appearance can be non-specific, mimicking other differential diagnoses, such as a Rathke's cleft cyst. However, the T2-weighted MRI appearances of ECs are generally hyper-intense and lesions show diffusion restriction. Treatment is surgical and yields good outcomes in most cases reported.

Dermoid Cyst of the Prepontine Cistern and Meckel's Cave: Illustrative Case and Systematic Review

Objective  Dermoid cysts are benign, congenital malformations that account for ∼0.5% of intracranial neoplasms. The authors describe a 42-year-old female with a prepontine dermoid cyst who underwent apparent gross total resection (GTR) but experienced cyst recurrence. To date, very few cases of prepontine dermoid cysts have been reported. The prevalent region where these cysts are located can be difficult to determine. In addition, the authors systematically review the literature to characterize the clinical presentation, anatomical distribution, and surgical outcomes of intracranial dermoid cysts. Design  Systematic review. Setting/Participants  PubMed, Web of Science, and Scopus databases. Main Outcome Measures  Extent of resection, symptom improvement, and recurrence rates. Results  A total of 69 patients with intracranial dermoid cysts were identified. Three (4.3%) intracranial dermoid cysts were located in the prepontine cistern. The average age of patients was 33.3 years. The most common presenting symptoms were headache (52.2%) and visual disturbances (33.3%). Intracranial dermoid cysts were distributed similarly throughout the anterior, middle, and posterior cranial fossae (29.0%, 36.2%, and 29.0%, respectively). GTR was achieved in 42.0% of cases. Thirty-four (49.3%) patients experienced symptom resolution. Recurrence rate was 5.8% at a mean follow-up of 2.1 years. Conclusions  Intracranial dermoid cysts most often present as headaches and visual disturbances. Intracranial dermoid cysts were found in the anterior, middle, and posterior cranial fossae at similar frequencies but with clear predilections for the Sylvian fissure, sellar region, and cerebellar vermis. Outcomes following surgical excision of intracranial dermoid cysts are generally favorable despite moderate rates of GTR.

Endoscopic endonasal resection of a giant middle fossa epidermoid cyst

Intracranial epidermoid cysts are rare. We report a case of a 55-year-old man who presented with trigeminal neuralgia and was found, on imaging, to have an epidermoid cyst located in the right middle fossa. He was managed via an entirely endoscopic endonasal approach. Postoperative magnetic resonance imaging confirmed complete removal of the mass, and the patient continued to have complete resolution of symptoms at a 1-year follow-up.

Indocyanine green fluorescence endoscopy at endonasal transsphenoidal surgery for an intracavernous sinus dermoid cyst: case report

The complete resection of intracavernous sinus dermoid cysts is very difficult due to tumor tissue adherence to important anatomical structures such as the internal carotid artery (ICA), cavernous sinus, and cranial nerves. As residual dermoid cyst tissue sometimes induces symptoms and repeat surgery may be required after cyst recurrence, minimal invasiveness is an important consideration when selecting the surgical approach to the lesion. We addressed a recurrent intracavernous sinus dermoid cyst by the endoscopic endonasal transsphenoidal approach assisted by neuronavigation and indocyanine green (ICG) endoscopy to confirm the ICA and patency of the cavernous sinus. The ICG endoscope detected the fluorescence signal from the ICA and cavernous sinus; its intensity changed with the passage of time. The ICG endoscope was very useful for real-time imaging, and its high spatial resolution facilitated the detection of the ICA and the patent cavernous sinus. We found it to be of great value for successful endonasal transsphenoidal surgery.

Smell sparing unilateral intracranial dermoid resection

Intracranial dermoid cysts are congenital ectodermal inclusion cysts that have a propensity to occur in the midline sellar, parasellar, or frontonasal regions. These cysts enlarge by means of glandular secretion and epithelial desquamation. Surgical resection has traditionally included a craniotomy, but endoscopic approaches are now used with increasing regularity. A binostril approach is normally used to access dermoid cysts due to the midline nature of the lesions. In this case report, we describe the successful surgical resection of a dermoid with 1.5-cm of intracranial extension using a unilateral endonasal endoscopic approach with no complications and with no postoperative anosmia. Although the unilateral endoscopic technique is not plausible for all epidermoid or dermoid cysts of the anterior cranial fossa, it should be considered a viable alternative technique when faced with a dermoid limited to one side of the falx cerebri.