Contrast-enhanced MRI of intrasellar arachnoid cysts: relationship between the pituitary gland and cyst

A Rare Case of an Intrasellar Arachnoid Cyst With Middle Cranial Fossa Extension

Intrasellar arachnoid cysts represent around 1% of all selar lesions. Generally, patients are asymptomatic and when they exhibit visual and/or hormonal disturbances, the indication for surgery is prompted. A 51-year-old woman with a known purely intrasellar arachnoid cyst diagnosed 23 years prior to presentation, evolved with gradual campimetric evaluation. Magnetic resonance imaging showed significant growth of the lesion, now extending into the left middle fossa through the cavernous sinus. The patient underwent cyst fenestration via the transsphenoidal approach. This is the first case in the literature of a patient with an intrasellar arachnoid cyst extending into the middle cranial fossa.

Endoscopic transnasal transsphenoidal management of sellar/suprasellar arachnoid cyst: A case report and literature review

Background

Arachnoid cysts (ACs) are collections of cerebrospinal fluids (CSFs) that develop within the arachnoid layer of the meninges. Sellar ACs are comparatively rare. In general, ACs account for approximately 1% of all intracranial mass lesions, and sellar ACs are 3% of all intracranial ACs. An endoscopic transnasal transsphenoidal approach for the treatment of ACs by fenestrating the cyst's wall and connecting with the subarachnoid space is the most optimal option.

Case Description

A 74-year-old woman whose sellar AC was diagnosed on magnetic resonance imaging a year ago was admitted to our hospital with complaints of bitemporal hemianopia and diminished visual acuity in the past 2 months. Sellar AC was diagnosed based on the clinical history and presentation, as well as neurologic, endocrinologic, and ophthalmologic examinations, including visual acuity and visual field examination, and additional imaging findings. The patient with a sellar/suprasellar AC was treated by an endoscopic transnasal transsphenoidal approach with cyst drainage and perforation of the lamina terminalis. Postoperatively, the visual disturbances improved markedly. No surgery-related complications occurred.

Conclusion

The endoscopic transnasal transsphenoidal approach remains a minimally invasive and preferred approach for the treatment of sellar/suprasellar ACs. Hermetically reconstructing the sellar floor is an effective method to prevent CSF leakage.

Approach to the Patient: Differential Diagnosis of Cystic Sellar Lesions

Cystic lesions arising in the sellar region are not uncommon and encompass cystic pituitary adenomas, Rathke cleft cysts, craniopharyngiomas, and arachnoid cysts. Their clinical presentation may be similar, including headache, visual field defects, and anterior pituitary hormone deficits, which makes differential diagnosis challenging. On the other hand, imaging features may indicate certain pathologies. In this approach to the patient, we describe the case of a patient who presented with right temporal hemianopsia and a sellar/suprasellar cystic lesion, which was determined to be Rathke cleft cyst. We discuss the imaging characteristics that may suggest a particular diagnosis between Rathke cleft cyst, cystic pituitary adenoma, craniopharyngioma, and arachnoid cyst and propose a flowchart for aiding in the imaging differential diagnosis.

Endoscopic treatment of sellar arachnoid cysts via a simple cyst-opening technique: Long-term outcomes from a single center

BACKGROUND

Sellar arachnoid cysts (SACs) are rare lesions that require treatment only if symptomatic. The endoscopic endonasal approach has been widely utilized. Despite their simple cystic appearance and the straight-forward surgical intervention there are important associated risks, with CSF leak being the prevalent one.

METHODS

A retrospective analysis of patients with pathologically confirmed SAC between January 2006 and December 2019 was conducted. A homogeneous simple cyst-opening technique and skull base reconstruction utilizing nasoseptal flaps was used.

RESULTS

Ten patients were identified (7 female and 3 male, median age was 54.5 years, range 20-77); 8 had newly diagnosed SACs whereas 2 recurrences from a previously microsurgically fenestrated SAC. Eight patients presented with visual symptoms (VS), 1 with VS and fatigue, and 1 with headaches. Neuro-ophthalmological and endocrinological assessments revealed visual field (VF) deficits in 6, visual acuity (VA) decline in 5 and hypopituitarism in 2 patients. Median calculated volume was 1.71 ml (range 0.27 - 2.54 ml). Postoperatively, no CSF leak and no further surgical complications were noted. VF improved in 4/6 while VA improved in 4/5 patients. Anterior pituitary function improved in 1, worsened in 1 and remained stable in 8 patients. One patient suffered diabetes insipidus. One recurrence was recorded 54 months postoperatively.

CONCLUSION

SACs can be effectively treated with a simple cyst-opening technique. The routine use of nasoseptal flaps significantly reduces the risk of CSF leak without compromising nasal quality of life in the long-term or mandating additional incisions. A long-term follow-up is important to monitor for late recurrences.

Endoscopic management of an intrasellar arachnoid cyst through the tuber cinereum in an adult: a case report

The transventricular endoscopic approach is an effective less invasive method for the management of symptomatic intrasellar arachnoid cysts in adults. The open area of the brain tissue defect in the infundibular recess caused by the upward compression of the cyst is a common target site for fenestration from the third ventricle. This report highlighted an alternative approach through the tuber cinereum (denoted as "trans-tuberal"), which enabled the treatment of symptomatic cases with a small opening for cyst fenestration in the infundibular recess.

[Update on intrasellar arachnoid cyst: a case study]

Les kystes arachnoïdiens intrasellaires sont des malformations bénignes. La localisation intrasellaire est extrêmement rare de l’ordre de 3%. Leur physiopathologie est encore mal élucidée. Nous rapportons un cas de kyste arachnoïdien intrasellaire à expansion suprasellaire dont la prise en charge avait consisté en une fenestration endoscopique par voie transsphénoïdale. Les aspects épidémiologiques, cliniques, physiopathologiques, radiologiques, thérapeutiques et évolutifs ont été analysés. Les procédures neuroendoscopiques sont de plus en plus utilisées pour la prise en charge chirurgicale. Leur pronostic est bon, et la récidive fréquente même après plusieurs années d’évolution.

Pituitary abscess following endoscopic endonasal drainage of a suprasellar arachnoid cyst: Case report and review of the literature

BACKGROUND

Arachnoid cysts are uncommon lesions of the sellar region, and only rarely require decompressive surgery to treat symptoms. Pituitary abscesses are another rare lesion, and are an uncommon complication of pituitary surgery. A previously healthy 45 year old woman presented with a new finding of bitemporal hemianopsia. Magnetic resonance imaging (MRI) showed a cystic sellar lesion with suprasellar extension and compression of the optic chiasm. Endoscopic transphenoidal surgery was performed and the lesion was found to be an arachnoid cyst. She was well immediately after the operation, but 1 week later presented with headaches, fever and worsening visual acuity. MRI showed a homogenous collection in the sellar region that was compressing the chiasm. The patient was treated with antibiotics, and a second transphenoidal operation was performed, with frank pus found in the pituitary fossa. Cultures of the fluid found during the operation grew Escherichia coli and Staphylococcus lugdunensis. Her symptoms resolved after the second operation, and formal visual fields and a pituitary hormone panel were normal at this time. We report on a rare case of a pituitary abscess complicating surgery for a sellar arachnoid cyst, and discuss management of these conditions.

Sellar Lesions/Pathology

The sellar region is a tiny anatomic compartment in which many lesions and developmental diseases can be found. If pituitary adenomas represent most of the sellar mass, it is important to recognize other pathologic conditions before any surgical procedure, because the optimal treatment may differ considerably from one lesion to another. A careful clinical evaluation followed by neuroimaging studies and an endocrinologic and ophtalmologic workup will lead, in most cases, to a diagnosis with near certainty. This article provides an overview of sellar diseases with emphasis on their most useful characteristics for clinical practice.

Intrasellar arachnoid cyst: A case report and review of the literature

INTRODUCTION

Arachnoid cysts (ACs) are frequently found on intracranial imaging studies but intrasellar arachnoid cysts are rarely encountered.

PRESENTATION OF CASE

We present a 49-year old patient who had headaches for 6 months and cystic sellar mass was found in his cranial imaging. We operated him by transnasal transsphenoidal route. Our intraoperative diagnosis was an arachnoid cyst and pathologic studies verified our observation. He did well postoperatively and after a 1year follow-up he was left free from future follow-ups.

DISCUSSION

As common cystic lesions occupying the sellar region can simulate ACs both clinically and radiologically, neurosurgeon can fail to include ACs in making the initial diagnosis preoperatively.

CONCLUSION

Although a rare entity, arachnoid cysts should be considered in the differential diagnosis of sellar region.

[Intra and suprasellar arachnoid cyst: contribution of MRI]

Les kystes arachnoïdiens intrasellaires sont rares et souvent étendus en suprasellaire. Leur diagnostic doit être évoqué devant toute formation de nature kystique dont le signal est identique à celui du liquide cérébro-spinal. Nous rapportons le cas d'un kyste arachnoïdien de siège intra et suprasellaire révélé par une baisse de l'acuité visuelle et une hémianopsie bitemporale dont l'exploration par l'IRM cérébrale retrouve la formation kystique de signal liquidien identique à celui du LCS, avec une prise de contraste localisée de la paroi postéro-latérale gauche du kyste qui correspond à la glande hypophysaire déplacée et étalée. Un abord chirurgical par voie trans-sphénoïdale a permis d’évacuer le contenu kystique et de décomprimer les voies optiques. L’évolution a été marquée par une amélioration immédiate des perturbations visuelles.

Pediatric intracranial arachnoid cysts: comparative effectiveness of surgical treatment options

PURPOSE

A variety of surgical approaches for the treatment of pediatric intracranial arachnoid cysts exist. In an effort to identify the optimal surgical treatment for this disorder, we developed a decision analytic model to evaluate outcomes of four surgical approaches in children. These included open craniotomy for cyst excision, open craniotomy for cyst fenestration, endoscopic cyst fenestration, and cystoperitoneal shunting.

METHODS

Pooled data were used to create evidence tables, from which we calculated incidence, relative risks, and summary outcomes in quality-adjusted life years (QALYs) for the four surgical treatments. Our study incorporated data up to 5 years postsurgery.

RESULTS

We analyzed 1,324 cases from 36 case series. There were no significant differences in outcome among the four surgical strategies. The QALYs (maximum of 5) for surgical approaches resulted in a range from 4.79 (for open craniotomy and excision) to 4.92 (for endoscopic fenestration).

CONCLUSIONS

Overall quality of life is comparable between patients undergoing open craniotomy for cyst excision or fenestration, endoscopic fenestration, and cystoperitoneal shunting up to 5 years after surgery. While each approach offers unique advantages and disadvantages, an individualized treatment strategy should be employed in the setting of surgical outcome equipoise.

Transsphenoidal cyst cisternostomy with a keyhole dural opening for sellar arachnoid cysts: technical note

A less invasive transsphenoidal approach with a keyhole dural opening for intrasellar arachnoid cysts is described. This approach was used to address seven sellar cystic lesions with suprasellar extension; they were six intrasellar arachnoid cysts (IACs) and one Rathke's cleft cyst (RCC). In all cases, preoperative MRI revealed cerebrospinal fluid (CSF) intensity on both T1- and T2-weighted images. On preoperative contrast-enhanced MRI, five of the six IACs manifested posterior displacement of the flattened pituitary gland toward the dorsum sellae; one of the six IACs and the RCC exhibited a flattened pituitary gland on the anterior surface of the cyst. Wide cyst cisternostomy through a keyhole dural opening was carried out safely using a microscope with the support of a thin angled endoscope (30° and/or 70°, diameter 2.7 mm). As we aimed to avoid iatrogenic injury of the pituitary function, we found it difficult to obtain a sufficiently wide and precise opening of the cyst wall when the pituitary gland was located on the anterior surface of the cyst wall. Our approach facilitates safe cyst cisternostomy as wide as that obtainable by transcranial manipulation. In addition, CSF leakage is prevented by dural plasty using the fascia lata and stitching with 6-0 monofilament sutures. This technique can be adapted to address various sellar cystic lesions. However, as the posterior or anterior displacement of the normal pituitary gland in the presence of IACs or RCCs, respectively, affects the width of the cyst opening, our technique is more suitable for IACs than RCCs.

[Intrasellar arachnoid cysts. Two case reports and literature review]

Intrasellar arachnoid cysts are an uncommon pathology, with only a few cases reported in scientific literature. Their physiopathology is still unknown, with different hypothesis about their development. Differential diagnosis with other cystic sellar lesions is difficult. We report two cases of two intrasellar arachnoid cysts that were treated surgically using transsphenoidal approach and present a review of the literature.

Transventricular endoscopic fenestration of intrasellar arachnoid cyst

BACKGROUND

To manage arachnoid cysts, incorporation with the normal circulation is the single most important determinant of success. Although the postoperative cerebrospinal fluid leakage rate is 3.9% for all cases of transsphenoidal surgery, it is 21.4% for intrasellar arachnoid cysts.

OBJECTIVE

To present a safe, relatively easy, and effective treatment option for very rare intrasellar arachnoid cysts.

METHODS

We performed a prospective study of intrasellar cystic lesions without a solid portion. Endoscopic exploration and fenestration were performed for all lesions under neuronavigational guidance. We analyzed presenting symptoms, endocrinological status, and magnetic resonance images.

RESULTS

There were 2 male and 4 female patients with a mean age of 45 years (range, 27-67 years). All patients presented with the visual disturbance of bitemporal hemianopsia. Four patients had endocrinological symptoms including galactorrhea, dysmenorrhea, and diabetes insipidus. Endoscopic fenestration of the cyst was successfully performed in all patients. All patients were confirmed to have a pure cystic lesion, namely an arachnoid cyst. The follow-up period was 10 months on average (range, 6-12 months). Visual disturbance improved in 5 patients. Endocrinological problems persisted in all patients for 3 months and then normalized, with the exception of the patient with diabetes insipidus. There was no evidence of recurrence in any of the 6 patients in the 12-month postoperative imaging studies (median follow-up of 10 months). Two patients showed syndrome of inappropriate antidiuretic hormone at 2 and 4 weeks after the operation, but antidiuretic hormones recovered to normal levels after this time point.

CONCLUSION

Endoscopic fenestration of an intrasellar arachnoid cyst is a safe and simple procedure without serious complications.

Endonasal management of sellar arachnoid cysts: simple cyst obliteration technique

Object

Symptomatic sellar arachnoid cysts (ACs) have typically been treated via the transsphenoidal route. After sellar cyst wall fenestration, some authors have advocated cyst wall resection and increasing communication between the AC and suprasellar subarachnoid space (SAS). This study is a report of the authors' experience using a simplified approach to reinforce a defective diaphragma sellae or unseen arachnoid diverticulum by deliberately not enlarging the AC-SAS communication and obliterating the cyst cavity with adipose tissue followed by skull base reconstruction.

Methods

A retrospective analysis was conducted of patients who underwent an endonasal transsphenoidal obliteration of symptomatic ACs with a fat graft and skull base repair.

Results

Between July 1998 and September 2010, 8 patients with a sellar AC were identified (6 women and 2 men, mean age 57 years). Clinical presentation included headache, pituitary dysfunction, and visual dysfunction (4 patients each group). Maximal cyst diameter averaged 22 mm (range 15–32 mm). In all cases the sellar communication to the SAS was deliberately not enlarged. The endoscope was used for visualization in 8 of 9 procedures. Postoperatively, headache improved in all 4 patients, vision in all 4 patients, and partial resolution of endocrine dysfunction (hyperprolactinemia and/or recurrent hyponatremia) occurred in 3 (75%) of 4 patients. No new endocrinopathy, CSF leak, meningitis, or neurological deficits occurred. Two patients experienced cyst reaccumulation: 1 symptomatic recurrence was treated with reoperation at 43 months postsurgery, and 1 asymptomatic partial recurrence continued to be monitored at 29 months postsurgery.

Conclusions

Sellar ACs can be effectively treated using endonasal fenestration and obliteration with fat with resultant reversal of presenting symptoms in the majority of patients. This simplified technique of AC cavity obliteration without enlarging communication to the SAS has a low risk of CSF leakage, and in most cases appears to effectively disrupt cyst progression, although longer follow-up is required to monitor for cyst recurrence.

INTRASELLAR ARACHNOID CYSTS

OBJECTIVE

To evaluate the clinical, endocrinological, and radiological presentation of nine cases of surgically verified intrasellar arachnoid cysts and to discuss the physiopathological mechanisms of formation of these cysts.

METHODS

Among 1540 patients presenting with pituitary lesions, nine presented with an intrasellar arachnoid cyst. Their charts were retrospectively reviewed.

RESULTS

Presenting symptoms included headache (n = 2), visual symptoms (n = 3), menstrual irregularities (n = 2), rapid weight gain (n = 1), vertigo (n = 1), and/or confusion (n = 1). Two cysts were discovered incidentally. T1-weighted magnetic resonance imaging scans showed an intrasellar cystic lesion in all cases, with a huge suprasellar extension in six cases. The cyst was of the same intensity as the cerebrospinal fluid (CSF) in only two patients. A transsphenoidal approach allowed the transdural aspiration of fluid and injection of a water-soluble contrast agent under mild pressure. In three patients, the contrast infiltrated along the pituitary stalk toward the subarachnoid spaces; in the other patients, it remained in the intrasellar compartment. Cyst membranes were removed as completely as possible with fenestration toward the subarachnoid spaces in communicating cysts. In spite of tight packing of the sella and sphenoid sinus, CSF fistulae requiring reoperation developed in two patients.

CONCLUSION

The clinical picture of an intrasellar arachnoid cyst resembles that of a nonfunctional pituitary adenoma. Magnetic resonance imaging scans typically show a cystic intrasellar lesion with suprasellar extension, containing isointense or, more often, hyperintense fluid on T1-weighted sequences. In spite of the risk of CSF fistulae, the preferred surgical approach is transsphenoidal. A physiopathological mechanism is proposed according to anatomic variations of the sellar diaphragma allowing penetration of subarachnoid spaces into the sellar compartment and their enlargement by a ball-valve mechanism.

Imaging of sellar and parasellar lesions

The sellar and parasellar region is an anatomically complex area where a number of neoplastic, infectious, inflammatory, developmental and vascular pathologies can occur. Differentiation among various etiologies may not always be easy, since many of these lesions may mimic the clinical, endocrinologic and radiologic presentations of pituitary adenomas. The diagnosis of sellar lesions involves a multidisciplinary effort, and detailed endocrinologic, ophthalmologic and neurologic testing are essential. CT and, mainly, MRI are the imaging modalities to study and characterise normal anatomy and the majority of pathologic processes in this region. We here provide an overview of the most relevant MRI and CT characteristics together with clinical findings of pituitary tumors, vascular, inflammatory and infectious lesions found in the sellar/parasellar region in order to propose an appropriate differential diagnosis.

Giant Intrasellar Arachnoid Cyst Manifesting as Adrenal Insufficiency Due to Hypothalamic Dysfunction-Case Report-

A 67-year-old man first noticed loss of pubic and axillary hair in 1992 and then a visual field defect in 2001. He experienced loss of consciousness attributed to hyponatremia in April 2002. Magnetic resonance imaging showed a giant intrasellar cystic mass, 40 mm in diameter, that had compressed the optic chiasm. The patient complained of chronic headache, and neurological examination revealed bitemporal hemianopsia. Preoperative endocrinological examination indicated adrenal insufficiency, and hypothyroidism due to hypothalamic dysfunction. The patient underwent endonasal transsphenoidal surgery. The cyst membrane was opened and serous fluid was drained. Histological examination identified the excised cyst membrane as arachnoid membrane. The patient's headaches resolved postoperatively, but the bitemporal hemianopsia and endocrinological function were unchanged. This arachnoid cyst associated with hypothalamic dysfunction might have been caused by an inflammatory episode in the suprasellar region.

MRI in the differential diagnosis of a sellar mass

Whilst pituitary adenomas are the commonest cause of a sellar mass, there are a number of other neoplastic, infectious, inflammatory, developmental and vascular aetiologies that should be considered by the radiologist. We discuss and illustrate these lesions and indicate the various magnetic resonance imaging features that are helpful in formulating an appropriate differential diagnosis.

Imaging of sella and parasellar disease

The sella and parasellar region may be affected by a variety of disease states. Diseases of this region often result in visual disturbances because of the proximity of the sella to the optic pathways and cranial nerves. Knowledge of the pathological conditions affecting the sella and surrounding structures is important for the orbital imager.