Parasellar Area Research Articles

Supraorbital Approaches for Anterior Skull Base and Parasellar Lesions: Insights From a Single-Center Experience.

Modern neurosurgery has undergone significant evolution to include minimally invasive procedures, with the supraorbital approach (SOA) being a prime example. In this study, we aim to explore the surgical techniques and outcomes of this approach in the surgical treatment of frontal lobe, anterior skull base, and parasellar lesions. This study included 33 patients aged 36-83 years who underwent surgery using the SOA for lesions in the inferior frontal lobe, anterior skull base, and parasellar area between 2015 and 2024. There were 25 cases of meningioma, 2 cases of brain abscess, 2 cases of glioma, and one case each of craniopharyngioma, hemangioma, metastasis, and Rathke's cleft cyst. The medical data and follow-up results were retrospectively analyzed. The mean size of lesion was 3.38±3.05 cm. The mean follow-up period was 48.8 months. Gross total resection was achieved in 25 patients (75.8%). There were no perioperative deaths, cases of cerebrospinal fluid rhinorrhea, or infections. Two cases of morbidity were reported as complications: one case of delayed intracerebral hemorrhage and one case of infarction due to vascular injury. All patients exhibited satisfactory cosmetic results. In comparison to the conventional pterional approach, the SOA represents a safe and effective keyhole method for the removal of both extra-axial and intra-axial skull base tumors. This is particularly beneficial for lesions in the orbitofrontal region and parasellar area, as it allows for minimal disruption of normal brain parenchyma. Moreover, the SOA promotes a swift recovery and short hospital stay. Additionally, the SOA yields superior cosmetic results, including the prevention of temporalis muscle atrophy.

CP-02. DAYTIME SLEEPINESS AND HEALTH-RELATED QUALITY OF LIFEIN PATIENTS WITH CHILDHOOD-ONSET CRANIOPHARYNGIOMA

Abstract BACKGROUND Adamantinomatous craniopharyngioma (CP) is a rare embryonal malformation originating from remnants of the craniopharyngeal duct and located in the sellar and/or parasellar area. Overall survival rates are high (92%), but frequently quality of life (QoL) is severely impaired in patients with CP involving hypothalamic structures. Tumor- and/or treatment-related hypothalamic lesions result in disturbances of circadian rhythms including increased daytime sleepiness. METHODS After a median follow-up interval of 10 years (range: 1-39 years), 119 patients (63 female/ 56 male) with CP, recruited in KRANIOPHARYNGEOM 2000/2007 and KRANIOPHARYNGEOM Registry 2019 between 2000 and 2022, were analysed for daytime sleepiness by Epworth scale (ES) and for QoL by EORTC QLQ-C30 questionnaire. RESULTS CP patients (n= 85) with pathologically increased ES score (ES score > 12) had worse QoL (p = 0.003), when compared with CP patients with normal ES score (n= 34). Pathologically increased daytime sleepiness (ES score) was negatively correlated with QoL (r= -0.395; p< 0.001). Surgical hypothalamic lesions (71% of patients) were associated with higher ES scores, whereas such impact could not be observed for presurgical hypothalamic involvement of CP (73% of patients). CONCLUSIONS As increased daytime sleepiness plays an important role for QoL in survivors of CP, treatment of disturbances of circadian rhythms with medication such as central stimulating agents is recommended. For prevention of increased daytime sleepiness, hypothalamus-sparing surgical treatment strategies should be considered as state of the art in patients with CP.

P-62 Silent Corticotroph Adenoma or Cyclic Cushing's Syndrome?

Abstract Introduction Silent corticotroph adenomas (pituitary neuroendocrine tumours (PitNET)) are a rare subset of nonfunctioning adenomas. The higher aggressiveness in terms of invasion and recurrence make these tumors dangerous and close follow-up in experienced centers is recommended. Clinical Case A 21-year-old obeseo (Body Mass Index:31.71) male patient unable to lose weight and complaining of headaches was referred to the Department of Neurosurgery for a pituitary macroadenoma. He had previously used liraglutide treatment Many purple striae were also seen on the body of the patient, who stated that his wounds did not heal easily. Visual acuity and visual field were normal. There was no neurodeficiency. Endocrinological evaluation revealed that the tumor was nonfunctioning (Table 1). Magnetic resonance imaging of the pituitary gland showed a mass lesion in the right side of the pituitary gland extending to the suprasellar and parasellar area (Knosp grade II) (Fig.1). The tumor with soft consistency was totally removed by endoscopic binostril transsphenoidal approach. The postoperative cortisol was 11.53 µg/dl (6.02-18.4) and free T4 was 1.32 ng/dL (0.93-1.7). The patient had a transient diabetes insipidus in the postoperative course, and he was discharged on the 4th day after surgery. Pathological examination revealed a pituitary adenoma immunostaining diffusely with ACTH, other hormones were unexpressed. Ki-67 was %2. Histological invasion of the dura was noted. Although the patient was clinically overweight and had purple striae suggestive of Cushing's syndrome (CS), his cortisol and ACTH levels were normal and suppressible with 1 mg dexamethasone suppression test. However, his tumour tissue showed diffuse ACTH expression, which led to the diagnosis of a silent ACTH adenoma. Since the clinical findings were not completely silent, could we assume that he suffered from cyclic CS? Cyclic (intermittent or periodic) CS is a condition characterised by alternating periods of transiently elevated cortisol levels followed by normal to reduced levels. The diagnosis of cyclic CS requires the presence of at least three confirmed episodes of elevated cortisol levels interspersed with two periods of normal cortisol levels. As we know, the cortisol secretion cycle is unpredictable and laboratory tests during the normal cortisol secretion period of the cyclic CS often show negative results as in our patient. Conclusion Postoperative follow-up of a silent corticotroph PitNET and cyclic CS patient, both of whom require close and life-long monitoring.Figure 1.Magnetic resonance imaging of the pituitary gland; coronal sections T1- weighted (a), T2-weighted (b), sagittal (c), and coronal (d) sections with T1 contrast enhancement. The mass lesion on the right side of the pituitary gland extending superiorly to the right internal carotid artery contains a hemorrhagic fluid component with heterogeneous contrast enhancement, is 16*12*9 mm in size, and corresponds to a hemorrhagic pituitary macroadenoma. Table 1.Hormonal values at presentationACTH, adrenocorticotropic hormone; DST, dexamethasone suppression test; fT4, free thyroxine; IGF-1, insulin-like growth factor 1; PRL, prolactin; TSH, thyroid-stimulating hormone.

THU221 Measurements Of Head Circumference During Developmental Monitoring Visits Before Diagnosis Of Pediatric Craniopharyngioma

Abstract Disclosure: J. Beckhaus: None. S. Boekhoff: None. L. Krieger: None. J. Peng: None. C. Friedrich: None. H.L. Muller: None. Craniopharyngiomas (CP) are congenital, benign, embryonic malformations which arise from ectoblastic remnants of Rathke’s pouch and are located in the (supra-)sellar region. Many patients show a reduced growth rate and an increased BMI early before the diagnosis of CP. However, it is unknown whether patients with CP present with increased head circumference before diagnosis. A cohort of 83 patients was screened for medical records of their developmental monitoring visits. We observed, that CP patients with hypothalamic involvement of their tumor tend to have an increased head circumference SDS before CP diagnosis. When comparing head circumference SDS before diagnosis at defined time points between birth and four years of age, all head circumferences were in the upper normal range. However, no statistically noticeable differences were found between hypothalamic involvement and no hypothalamic involvement of the tumor. Congenital embryonic malformations such as CP located in the parasellar area can have impact on cerebrospinal fluid circulation and lead higher head circumferences due to hydrocephalus early before diagnosis. Our results show, that head circumference SDS could be an effective early-indicator for CP. A standardized procedure for head circumference measurements during developmental monitoring visits should be implemented in clinical care. We anticipate that our study is the starting point for prospective studies with larger sample size to assess the potential predictive value of head circumference measurements for an early CP diagnosis. Presentation: Thursday, June 15, 2023

THU100 Case Of A Large Suprasellar-clival Mass: Prolactinoma Vs Paraganglioma

Abstract Disclosure: L.N. Madera Marin: None. Y. Rivera-Nieves: None. M.A. Ortiz-Rivera: None. A. Rosado-Burgos: None. L. El Musa Penna: None. W. Medina-Torres: None. L. Sepulveda-Garcia: None. M. Ramirez: None. L.A. Gonzalez-Rodriguez: None. M. Alvarado: None. N. Canales: None. Introduction Prolactin secreting adenomas comprise 30-40% of all pituitary adenomas. Generally, serum prolactin levels correlate with tumor size. Giant prolactinomas measure >4 cm, most have mass related clinical effects. Even large masses respond to cabergoline. Some may require surgical intervention. We present a case of a large pituitary mass associated with elevated prolactin levels, but with an interesting histopathologic analysis. Patient Description 30 y/o male patient with new onset decreased peripheral vision. Retinologist evaluation showed no abnormalities. Laboratories done by PCP found with altered thyroid function tests, but no treatment offered at the time. Two months later, the patient complained of worsening peripheral vision and was found with a left dilated pupil. A head CT scan was performed that showed a large brain mass. Admitted for urgent neurosurgery evaluation and high dose dexamethasone was initiated. ROS was remarkable for weight gain over the past year, and decreased morning erections, although denied decreased libido or erectile dysfunction. MRI showed an infiltrative skull base tumor extending from the clivus to the parasellar area encasing the left cavernous segment of the internal carotid artery with expansion of the sella obliterating the pituitary gland, and extension into the left optic canal. Pre-operative laboratories: Prolactin >877 ng/ml (2-17ng/ml), Cortisol 1.80 mcg/dL (4-22 mcg/dL), TSH 1.45 uIU/ml (0.4-4.0 uIU/ml), Sodium 142mMol/L (135-145mMol/L). Patient underwent left pterional craniotomy. Initial intra-operative pathology: “Positive for Neoplasia”. Post-operative laboratories: Prolactin >877 ng/ml, TSH 0.229 uIU/ml, FSH <0.30 mIU/ml (1.2-7.8 mIU/ml), and LH 0.16 mIU/ml (1.5-9.3 mIU/ml). Case Outcomes/Discussion Central hypothyroidism and hypogonadism confirmed, secondary hypocortisolism could not be assessed due to emergent corticosteroid infusion upon admission. A presumptive diagnosis of a giant prolactinoma was made for which cabergoline therapy was initiated. Final pathologic diagnosis revealed a paraganglioma. Urine fractionated metanephrines and catecholamines were normal. Immunostaining for prolactin requested. Paragangliomas arise from neuroendocrine cells, from either sympathetic or parasympathetic ganglia and can be solitary or multiple. Skull base and neck paragangliomas are usually benign while ∼20% of abdominal paragangliomas (sympathetic) are malignant. Anterior skull base paragangliomas are predominantly located in the sella and are rare but have been described in the literature. Very rare cases of pheochromocytomas or paragangliomas associated to pituitary adenomas have been reported. It has been named as the three P association, thought to be related to succinate dehydrogenase B and D mutations. Moreover, there are no cases in the literature of paragangliomas secreting prolactin. Presentation: Thursday, June 15, 2023

Recurrent craniopharyngioma

Craniopharyngioma is a rare embryonic malformation tumor in the sellar and parasellar area of low histological grade. Local recurrence is frequent, being of great importance the use of the preoperative visual field as a clinical predictive indicator; and its postoperative outcome. The objective of this report is to recognize a recurrence in the event of small changes in visual acuity or campimetric alterations in patients with a history of this tumor. Clinical case: A 10-year-old girl presents to the clinic with a history of craniopharyngioma operated on a year earlier, with both atrophic optic nerves and decreased visual acuity. Complementary studies and urgent referral to the pediatric neurosurgeon were carried out, who detected intracranial hypertension secondary to recurrence of the craniopharyngioma, leading to its surgical removal. Conclusion: It is important to highlight the requesting of a visual field both for the detection of possible recurrences and for the follow-up of the craniopharyngioma, considering its high recurrence rate.

Endoscopic Endonasal Surgery for Uncommon Pathologies of the Sellar and Parasellar Regions.

Endoscopic skull base surgery has become an integral part of the present neurosurgical armamentarium. The pioneering efforts in which the purely endoscopic transsphenoidal approach was introduced have triggered a growing tide of using the endoscopic endonasal procedures for a large variety of skull base lesions. Because of their anatomical peculiarities, lesions of the sellar and parasellar regions lend themselves very well to the endoscopic endonasal approaches. Apart from the common pathological entities, many other less frequent pathologies are encountered in the sellar and parasellar area. In this chapter, we review the surgical technique of the endoscopic endonasal transsphenoidal approach and its extensions applied to a variety of rare and uncommon pathological entities involving the sella turcica and clivus. An overview of these pathological entities is also presented and exemplified.

ODP362 An Unexpected Finding of Adamantinomatous Type Craniopharyngioma in the Late Seventh Decade of Life: a case report

Abstract Background Craniopharyngioma is a rare solid, mixed solid, and benign cystic neoplasm derived from remnants of Rathke's pouch from the sellar region and its surroundings parasellar area. It mainly has two major histopathological subtypes, Adamantinomatous and Papillary. The adamantinomatous subtype is more common in children, and the papillary subtype is more common in adults. Clinical case: A 66-year-old male with no known endocrinological disorder presented with progressive fatigue, decreased oral intake, lightheadedness, nausea, visual changes, low libido, myalgia, nausea, vomiting, polyurea, headache, visual field defects, and seizure-like activities requiring hospital admission. The endocrinological workup revealed a deranged HPA axis (panhypopituitarism). MRI revealed 3 cm macroadenoma within the pituitary gland. An endonasal transsphenoidal resection of pituitary mass resection with abdominal fat graft was done as definitive treatment along with correction of the multiple endocrinological derangements. The surgical tissue biopsy revealed a rare with adamantinomatous type Craniopharyngioma WHO Grade I. He was discharged on testosterone supplements, hydrocortisone, levothyroxine, and Desmopressin with significant improvement in his symptoms. Conclusion Craniopharyngioma (CP) is a rare benign intracranial mass (incidence 0.5-2/100000) that can present with extensive endocrinological dysfunction. However, due to the lack of patient-level data and reporting of adult-onset craniopharyngiomas, it can be easily missed during the initial presentation. Not considering craniopharyngioma in differential diagnoses may result in delayed diagnosis and adverse outcomes. Although the papillary CP type is more common among adults, occasionally, adamantinomatous type CP may occur in this group of patients. Presentation: No date and time listed

Endoscopic Subtemporal Epidural Key-Hole Approach: Quantitative Anatomic Analysis of Three Surgical Corridors

The endoscope-assisted subtemporal key-hole epidural approach (ESKEA) has been recently described. The aim of this study was to measure working volumes and exposure of key areas of the middle cranial fossa provided by this approach. Four fresh frozen cadaver heads were dissected to analyze 3 modular corridors (1A, 1B, and 2) harvested through ESKEA. A step-by-step dissection was performed, and key anatomic landmarks were recorded. A GTxEyesII-ApproachViewer was used to quantify the working volume and exposure of 4 different regions (sphenoorbital, parasellar, superior petrous apex, and squamopetrous). For each corridor, 3 incremental degrees of temporal dural retraction (5, 10, and 15 mm) were tested. The working volume of all corridors progressively increased with degree of retraction: Corridors 1A, 1B, and 2 showed a gain in working volume of 21%, 27%, and 19% from 5 mm to 10 mm retraction, respectively, and a gain of 40%, 45%, and 44% from 5 mm to 15 mm retraction, respectively. The sphenoorbital area was exposed (27%-45%) through corridor 1A, and exposure significantly increased with the degree of retraction. Corridor 1B provided optimal exposure of parasellar areas (86%-100%) and superior petrous apex (70%-87%) regardless of the degree of retraction. The squamopetrous area was satisfactorily addressed through corridor 2 (88%) only with the highest degree of retraction. ESKEA can be conceived as a modular approach: the 3 surgical corridors have specific working volumes, which are clearly influenced by the degree of temporal lobe retraction, and provide exposure of different middle cranial fossa areas.

Up-To-Date Magnetic Resonance Imaging Findings for the Diagnosis of Hypothalamic and Pituitary Tumors.

Magnetic resonance imaging (MRI) is the preferred imaging technique for the sellar and parasellar regions. In this review article, we report our clinical experience with MRI for hypothalamic and pituitary lesions, such as pituitary adenomas, craniopharyngiomas, Rathke cleft cysts, germinoma, and hypophysitis with reference to the histopathological findings through a review of the literature. Our previous study indicated that three dimensional-spoiled gradient echo sequence is a more suitable sequence for evaluating sellar lesions on postcontrast T1 weighted image (WI). This image demonstrates the defined relationship between the tumor and its surroundings, such as the normal pituitary gland, cavernous sinus, and optic pathway. We demonstrated the characteristic MRI findings of functioning pituitary adenoma. In growth hormone-producing adenoma, signal intensity on T2WI is important to differentiate densely from sparsely granulated somatotroph adenomas. In prolactin-producing pituitary adenomas, distinct hypointense areas in early phase on T2WI, possibly owning to diffuse hemorrhage, indicate pronounced regressions of invasive macroprolactinomas during cabergoline therapy. The two histopathological subtypes, adamantinomatous and squamous papillary craniopharyngioma, differ in genesis. Calcified tumors are mostly adamantinomatous type. On MRI, these lesions have a heterogenous appearance with a solid portion and cystic components. The solid portions and cyst wall enhance heterogeneously. Although cyst fluid of Rathke cleft cysts show variable intensities on MRI, intracystic waxy nodule can be hypointense on T2WI. The enhancing cyst wall may contain the squamous metaplasia. Cystic lesions of the sellar and parasellar areas may be difficult to differentiate on a clinical, imaging, or even histopathological basis.

Clinical Presentation of Patients with Pituitary Tumour and its Correlation to Magnetic Resonance Imaging: An Observational Study

Introduction: Pituitary tumours are common intracranial tumours affecting mainly the 4th to 7th decade of life. A detailed understanding of these pituitary tumour patients, especially regarding their clinical and MRI profile would help in its early detection.It also help in deciding upon further management (medical or surgical or radiation), thus helping in improved outcome. Aim: To find out the common clinical presentations and the MRI findings of pituitary tumour. Materials and Methods: A cross-sectional observational study was carried out among 88 patients admitted with diagnosis of pituitary tumour in a tertiary care center from 1st June 2018 to 30th September 2019. The study involved initial clinical assessment followed by MRI brain of all the patients included in the study. To find out relationship between imaging findings and clinical symptoms statistical analysis was done. Results: The most common clinical presentations were headache in 55 patients (commonly throbbing type in frontal region) and visual field defects in 52 patients (uni/bitemporal hemianopia). A 51 (58%) patients had suprasellar extension and 35 (39.8%) patients had tumour already progressed to parasellar extension stage at time of detection of adenoma. Most of the patients detected with pituitary tumours (i.e., 63.6%) had grade two invasion. Four incidental adenomas were detected and none of them had parasellar extension. Among 35 patients with parasellar extension, 27 (77.1%) patients had visual disturbance. In 45 (51.1%) patients without parasellar extension had no sellar floor involvement. Visual disturbance was significantly associated with the parasellar extension of the tumour. Conclusion: Headache and visual field defects were the most common clinical presentation among pituitary tumour patients. Patients with tumours having parasellar extension are more likely to have visual disturbance than with patients having only suprasellar extension. Radiologically, pituitary tumours tend to expand only into suprasellar area, then it involves the parasellar area, followed by sellar floor which occurred last.

Chapter 6 - Magnetic resonance imaging of the hypothalamo–pituitary region

The diagnosis and management of mass lesions in the sellar and parasellar areas remain challenging. When approaching patients with possible sellar or hypothalamic masses, it is important not only to focus on imaging but also detect possible pituitary hormone deficits or excess, in order to establish an appropriate diagnosis and initiate treatment. The imaging modalities used to characterize hypothalamic and pituitary lesions have significantly evolved over the course of the past several years. Computed tomography (CT) and CT angiography play a major role in detecting various sellar lesions, especially in patients who have contraindications to magnetic resonance imaging (MRI) and can also yield important information for surgical planning. However, MRI has become the gold standard for the detection and characterization of hypothalamic and pituitary tumors, infections, cystic, or vascular lesions. Indeed, the imaging characteristics of hypothalamic and sellar lesions can help narrow down the differential diagnosis preoperatively. In addition, MRI can help establish the relationship of mass lesions to surrounding structures. A pituitary MRI examination should be obtained if there is concern for mass effect (including visual loss, ophthalmoplegia, headache) or if there is clinical suspicion and laboratory evidence of either hypopituitarism or pituitary hormone excess. The information obtained from MRI images also provides us with assistance in planning surgery. Using intraoperative MRI can be very helpful in assessing the adequacy of tumor resection. In addition, MRI images yield reliable data that allow for noninvasive monitoring of patients postoperatively.

Transarterial Embolization of a Parasellar Hypervascular Tumor.

Embolization of hypervascular tumors has been widely performed for over four decades, particularly for preoperative meningioma. Several benefits of preoperative embolization have been reported, including reduced blood loss, surgical time and surgical complications, and improved outcomes. However, the technical details of both embolization and surgical procedures, and lesions widely vary. Thus, the actual benefits of preoperative embolization have not been clarified by prospective randomized studies. Procedure-related complications due to embolization developed in 3%-12% in previous studies. For parasellar lesions, both surgical resection and embolization have a higher risk of complication than for lesions at other locations because of the complicated neurovascular anatomy in the parasellar area. Therefore, close attention should be paid to the detailed vascular anatomy, embolic material, and related information for embolization and resection in individual cases to improve patient outcomes.

Arterial Anatomy of the Parasellar Area.

The arterial anatomy of the parasellar area is complex in that it deals with extracranial-intracranial anastomosis and supply to various cranial nerves in a small area. Pathologies such as hypervascular tumors and shunts are not uncommon and require good knowledge of anatomy in planning the treatment. In this article, the basic anatomy of the arterial supply in this region is discussed, covering the origins, territories, relation to the cranial nerves, and the connections among different systems.

Pituitary Adenomas and Invasiveness from Anatomo-Surgical, Radiological, and Histological Perspectives: A Systematic Literature Review.

Invasiveness in pituitary adenomas has been defined and investigated from multiple perspectives, with varying results when its predictive value is considered. A systematic literature review, following PRISMA guidelines, was performed, searching PubMed and Scopus databases with terms that included molecular markers, histological, radiological, anatomical and surgical data on invasiveness of pituitary adenomas. The results showed that differing views are still present for anatomical aspects of the sellar region that are relevant to the concept of invasiveness; radiological and histological diagnoses are still limited, but might improve in the future, especially if they are related to surgical findings, which have become more accurate thanks to the introduction of the endoscope. The aim is to achieve a correct distinction between truly invasive pituitary adenomas from those that, in contrast, present with extension in the parasellar area through natural pathways. At present, diagnosis of invasiveness should be based on a comprehensive analysis of radiological, intra-operative and histological findings.

Examination of the Topographical Anatomy and Fetal Development of the Tendinous Annulus of Zinn for a Common Origin of the Extraocular Recti.

The aim was to clarify the topographical anatomy of the common tendinous ring for the four rectus muscles in both adults and fetuses. We histologically examined the annular ligament for a common origin of the extraocular rectus muscles using 10 specimens from elderly individuals and 31 embryonic and fetal specimens. At 6 to 8 weeks, each rectus carried an independent long tendon, individually originating from the sphenoid. Notably, we found additional origins from the optic or oculomotor nerve sheath. At 12 to 15 weeks, the lateral, inferior, and medial recti muscles were united to provide a C-shaped musculofibrous mass that was separated from the superior rectus originating from the edge of the optic canal opening. Morphologic features at 31 to 38 weeks were almost the same as those at 12 to 15 weeks, but the long and thick common tendon of the three recti reached the sphenoid body in the parasellar area. In adults, a ring-like arrangement of the rectus muscles ended at a site 8.1 to 12.0 mm anterior to the optic canal opening and independent of the superior rectus origin, the lateral, inferior, and medial recti formed a C-shaped muscle mass. The united origins of the three recti changed to a fibrous band extending along the superomedial wall of the orbital fissure. Consequently, none of the specimens we examined exhibited an annular tendon representing a common origin of the four recti, suggesting that the common tendinous ring includes only medial, lateral, and inferior rectus muscles with the superior rectus taking its origin independently.

Endoscopic Endonasal Transsphenoidal Surgery: History and Evolution

In previous decades, extensive and disfiguring transfacial and/or transcranial approaches were used to reach the sellar and parasellar areas. However, these surgical routes were burdened by severe complications and high mortality rates. Recently, the development of endoscopic endonasal techniques has revolutionized the surgical strategies for approaching the sella and adjacent areas and increased the development of transsphenoidal surgery. With these techniques, surgeons have been able to overcome the visual limitations of the open surgical approaches and access areas previously hidden from view. After the contributions of the Pittsburgh duo, Carrau and Jho, pioneers of pure endoscopic surgery, our school began to implement this technique, introducing technical innovations and variations, describing the anatomical details and defining new routes, and playing a key role in its widespread clinical application.

Cavernous Sinus and Parasellar Region: An Endoscopic Endonasal Anatomic Cadaver Dissection.

The aim of this study was to investigate the neurovascular structures of the cavernous sinus with the endonasal endoscopic transpterygoid approach on fresh human cadavers. Additionally, the course of internal carotid artery (ICA) and relevant anatomy was thoroughly investigated to refine the anatomical landmarks, exposure difficulties, potential complications, and limitations using the endonasal endoscopic technique. This study was carried out at an otolaryngology department of a tertiary medical center between June 2014 and June 2015. The surgical dissection was performed on 10 fresh human cadaver specimens using paranasal sinus and skull base endoscopic instruments. Cavernous sinuses and parasellar area were explored via an endoscopic endonasal transpterygoid approach. Dehiscence was present in 5 (25%) cavernous ICAs. Projection of the cavernous ICA on the whole lateral sphenoid wall was prominent in 6 (%30) sphenoid sinuses. Anterior curve was prominent in 12 (60%) cavernous ICAs, whereas posterior was prominent in 7 (35%). Mean distance between the lateral wall of eustachian tube orifice and petrous ICA was 19.50 ± 1.05 mm (range 18-22 mm). Cranial nerves of the cavernous sinus showed no variation. Control of the ICA is critical during the endonasal endoscopic approach to the cavernous sinus and skull base. The vidian nerve is a reliable and important landmark to the petrous ICA in the transpterygoid approach. Dissection of the eustachian tube and its relation to the ICA has to be kept in mind during nasopharyngeal surgery.

Bilateral oculomotor ocular neuromyotonia: a case report

BackgroundOcular neuromyotonia (ONM) is characterized by episodic diplopia, which is usually triggered by prolonged eccentric gaze of the affected extraocular muscles. The spell is characterized by involuntary, occasionally painful, sustained contraction of one or more extraocular muscles innervated by the oculomotor, trochlear, or abducens nerve. ONM usually occurs as a late consequence of radiotherapy around the parasellar area, although idiopathic cases have been reported. Most cases are unilateral; however, bilateral ONM has occasionally been described.Case presentationA 60-year-old woman presented with a 4-month history of episodic, painful, horizontal binocular diplopia. She underwent external beam radiotherapy to the skull base for treatment of nasopharyngeal carcinoma. The tumor was well controlled. General neurological examination findings were unremarkable. Neuro-ophthalmic examination revealed normal visual acuity, visual fields, pupils, and fundi. Ocular alignment showed orthotropia with normal ocular motility. Myasthenic eyelid signs were absent. However, she developed episodes of involuntary sustained contraction of the medial rectus muscle following prolonged eccentric gaze toward the affected medial rectus muscle, which resulted in esotropia upon returning to the primary position. The esotropic episodes spontaneously resolved after approximately 2 min. These spells affected both medial rectus muscles. Both pupils remained normal throughout the examination. Magnetic resonance imaging revealed neither brain parenchyma/brain stem lesions nor tumor recurrence. Her symptoms were successfully treated with carbamazepine.ConclusionsEpisodic esotropia in the adducting eye following prolonged horizontal eccentric gaze is a significant characteristic of ONM affecting the bilateral medial rectus muscles (i.e., bilateral oculomotor ONM). In spite of its extreme rarity, ONM should be considered as a differential diagnosis of episodic diplopia, especially in patients with a history of radiotherapy around the parasellar area. Careful examination with prolonged eccentric gaze should be performed to achieve a correct diagnosis and avoid an extensive unnecessary workup.

Extradural anterior clinoidectomy in the management of parasellar meningiomas: Analysis of 13 years of experience and literature review

Background and aimThe extradural anterior clinoidectomy (EAC) is a key microsurgical technique that facilitates the resection of tumours located in the parasellar region. There is currently no consensus regarding the execution of the procedure via extradural or intradural nor scientific evidence that supports its routine use. The purpose of this article is to expose our experience in performing EAC as part of the management of the parasellar meningiomas. Materials and methodsA retrospective analysis of the EAC for parasellar meningioma resection performed in our centre between 2003 and 2015 was done. A total of 53 patients were recorded. We analysed our series focusing on visual outcomes, resection rates and complications. Through an extensive bibliographic research, we discussed the advantages and disadvantages of the EAC, technical considerations, comparison with the intradural clinoidectomy and its visual impact. ResultsThe most frequent tumours were anterior clinoidal meningiomas (33.9%). The most common initial symptoms were decreased visual acuity (45.3%) and headache (22.6%). A gross total resection was achieved in 67.9%, being subtotal in the remaining 32.1%. Regarding the visual deficits 67.9% of the patients presented clinical stability, 22.6% improvement and 9.4% worsening. The degree of tumour resection did not significantly influence post-surgical visual outcomes, either visual acuity (p=0.71) or campimetric alterations (p=0.53). 24.5% of the patients experienced III nerve transient paresis and 1.9% permanent. The postoperative cerebrospinal fluid leak rate was 3.8%. Mortality rate was 0%. The mean follow-up was 82.3 months. ConclusionsIn our experience, EAC is a safe technique that facilitates the resection of the meningiomas located in the parasellar area, helps to achieve early tumour devascularisation, reduces the need for retraction of the cerebral parenchyma and could play a positive role in the preservation of visual function and the appearance of tumour recurrences in the anterior clinoid process (ACP).