Diaphragma Sellae Research Articles

Predicting Arachnoid Membrane Descent in the Chiasmatic Cistern in the Treatment of Pituitary Macroadenoma.

ObjectivePreoperative prediction of the arachnoid membrane descent in pituitary surgery is useful for achieving gross total removal and avoiding cerebrospinal fluid leakage resulting from tearing of the arachnoid membrane in the chiasmatic cistern. In this study, we analyzed the patterns of arachnoid membrane descent during or after pituitary tumor surgery and identified the factors related to this descent. MethodsAnalysis was restricted to pituitary macroadenomas not extending into the third ventricle or over the internal carotid artery. To minimize confounding factors, patients who underwent revision surgery, those who had a torn arachnoid during operation or small medial diaphragma sellae (DS) opening, and subtotal resections were excluded. We enrolled 41 consecutive patients in this retrospective analysis. The degree of arachnoid descent was categorized using intraoperative videos. Preoperative magnetic resonance findings, including tumor height, suprasellar extension, and variables including DS area and medial opening size, tumor composition, and displacement of the pituitary stalk and gland were evaluated to determine their correlations with arachnoid membrane descent. ResultsArachnoid membrane descent was significantly correlated with DS area and medial opening size. Based on T2-weighted images (T2WI) magnetic resonance (MR) images, tumor composition was significantly associated with arachnoid membrane descent. Other factors were not significantly correlated with arachnoid membrane descent. ConclusionT2WI of tumor composition and preoperative MR imaging of DS area and medial opening provided valuable information regarding arachnoid membrane descent. These parameters may serve as fundamental measures to facilitate complete resection of pituitary macroadenomas.

Surgery for diaphragma sellae meningioma: how I do it

BackgroundSurgery for diaphragma sellae meningiomas (DSM) remains challenging due to the intimate neurovascular relationships of the tumor. Excision of DSM along with a decompression of the optic apparatus requires a good knowledge of the skull base anatomy and a precise preoperative evaluation of the tumor extensions.MethodWe describe the key steps of transcranial approach for DSM with a video illustration. The surgical anatomy is described along with the advantages and limitations of this approach.ConclusionsThe transcranial approach allows a safe tumor excision with an early and adequate control of the neurovascular structures, while minimizing postoperative CSF rhinorrhea.

Tuberculum Sellae Meningiomas: Outcome of Twenty-eight Cases after Surgery

Objective: To present this series of surgically treated tuberculum sellae meningiomas with particular regard to visual compromises
 Methods: A retrospective analysis was done on 28 patients (21 females) with meningiomas originating from the tuberculum sellae who underwent surgery between 2010 and 2019. The standard surgical approach of pterional craniotomy. Twelve meningiomas extended posteriorly onto the diaphragma sellae, 13 anteriorly to the planum sphenoidale, and 3 to the anterior clinoid process. 21 tumours involved the optic canal, one bilaterally. Follow up ranged from 6 to 12 months.
 Results: Total microscopic resection was achieved in 28 patients. Median tumour size was 3.2 cm. Postoperatively, visual acuity improved in 19 patients and deteriorated 3. Preoperative and postoperative visual acuity worsened with increasing duration of preoperative symptoms and with increasing age. Extension into the intraconal space was a negative predictor. Recurrence occurred in one cases. One patients died from causes unrelated to the tumour.
 Conclusions: In the majority of patients with tuberculum sellae meningiomas, total resection may be achieved through a pterional approach with minimal complications.
 Bang. J Neurosurgery 2020; 10(1): 39-44

Navigating a Carotico-Clinoid Foramen and an Interclinoidal Bridge in the Endonasal Endoscopic Approach: An Anatomical and Technical Note.

Objective The carotico-clinoid foramen and interclinoid bridge are two anatomical variants of the sellar region. If these anatomical variants go unrecognized and are not managed safely by the surgeon during expanded endoscopic endonasal surgery for a posterior clinoidectomy, a carotid artery injury may occur. We summarize a method to safely navigate in the presence of the carotico-clinoid foramen and interclinoid bridge in an endoscopic endonasal approach. Study Design The study involves cadaveric dissection and management of the anatomical variants. Setting The study took place in a cadaveric dissection laboratory. Participants The object of study is one cadaveric head. Main Outcome Measures After discovering the two variants in both cavernous sinuses of a cadaveric head, we established a stepwise coping strategy to avoid carotid artery injury while performing an endoscopic endonasal bilateral interdural pituitary transposition, and we report the final view after endoscopic management. Results Debulking of the middle clinoid process can decrease the obstacle effect, and the pituitary transposition can be performed medial to the ossified carotico-clinoid ligament. Disconnection of the interclinoid bridge is the prerequisite to an effective posterior clinoidectomy, and distinguishing the transition between the sellar diaphragm and the interclinoid bridge is essential. Conclusion In the presence of both the carotico-clinoid foramen and the interclinoid bridge, a bilateral interdural pituitary transposition can still be performed, although preoperative strategic preparation, full inspection, and stepwise disconnections are of paramount importance in such a scenario to avoid cavernous carotid artery injury.

Arachnoid prolapse in endoscopic transsphenoidal surgery of pituitary adenoma, technical note

Purpose An arachnoid prolapse after endoscopic transsphenoidal surgery for a pituitary adenoma is an uncommon, but important, phenomenon which should be managed. We have evaluated the efficacy of a new simple technique to correct the prolapsed arachnoid following endoscopic surgery of pituitary adenomas. Methods A total of 1352 patients with pituitary adenomas, 24–76 years old, who underwent full endoscopic transsphenoidal surgeries between February 2014 and February 2019 in Erfan and Loghman Hakim hospitals. 46 patients with arachnoid prolapse participated in this study and41 patients completed the study. Arachnoid prolapse was repaired by bipolar cauterization with either autologous fat grafts (36 patients) or without autologous fat grafts (5patients). Results Of 41 patients who completed the study, all except one, had large adenomas with significant suprasellar extension and enlarged diaphragma sellae. All patients had arachnoid prolapse at the end of the tumor removal stage and 13 patients had very minor intraoperative CSF leakage. Prolapsed arachnoid was repaired using a bipolar cautery with or without the autologous fat graft. During the postoperative follow-up period, none of the patient experienced early or delayed postoperative CSF leakage, meningitis, visual deterioration, delayed epistaxis, cranial nerve palsy, recurrence, or death. Conclusion Bipolar cauterization is a safe, effective technique to repair a suprasellar arachnoid prolapse during reconstruction of the sellar floor following endoscopic transsphenoidal pituitary surgery.

Surgical Complications of Endoscopic Endonasal Trans-Sphenoidal Approach for Pituitary Tumors

Background: Pituitary macro-adenomas form about 10% of intracranial tumors. Most of them are non-functioning and manifestations are due to space-occupying effects or clinical hypo-pituitarism. Functioning adenomas result in the conditions of Cushing’s disease, galactorrhoea/oligo/amenorrhoea and acromegaly. Non-functioning pituitary tumors may also produce hyper-prolactinaemia due to dis-inhibition of the effects of hypothalamic dopamine on lactotroph cells. Aim of the work: Detection of surgical complications of endoscopic endo-nasal trans-sphenoidal surgery for pituitary tumors and how to avoid and manage them. Material and Methods: This study is conducted upon 40 cases diagnosed to have pituitary tumors, operated upon in department of Neurosurgery at Al-Azhar University Hospitals, and Shibin Al.Kawm teaching hospital from March 2017 to March 2019. prospectively collected and retrospectively analyzed. Results: 11 patients suffered complications, as CSF leak, intra-operative bleeding, and herniation of diaphragm sellae. Conclusions: Endoscopic Trans-sphenoidal approach usually is the method of choice for treating pituitary tumors due to lower risk of complications.

T158. NO ALTERATION OF PITUTARY VOLUME IN PATIENTS WITH FIRST-EPISODE SCHIZPHRENIA BUT A TREND OF ENLARGEMENT IN NON-PSYCHOTIC FIRST-DEGREE RELATIVES

BackgroundThere is growing evidence suggesting that the abnormal pituitary volume (PV) may be an essential deficit in schizophrenia spectrum disorders, and PV may change depending on the stage of the illness. However, previous studies assessing PV in schizophrenia spectrum disorders, especially in ultra-high risk individuals, were confounding. The present study aimed to assess whether there would be alteration of the PV in patients with first-episode schizophrenia and their non-affected first-degree relatives.MethodsThis study recruited 147 subjects, including subjects with 62 first-episode schizophrenia (31 man, 31 female), 25 non-psychotic first-degree relatives (11 male, 14 female), and 60 healthy controls (30 male, 30 female). All of them underwent a T1 weighted image magnetic resonance imaging using 3T MRI Scanner (Siemens, Germany). All volumes were examined with the 3D-Slicer 4.10.1 (Surgical Planning Laboratory, Brigham and Women’s Hospital, USA; http://www. slicer.org/). The PV was traced in all coronal slices with well-defied boundaries (such as diaphragma sellae (superiorly), the sphenoid sinus (inferiorly), the cavernous sinuses(bilaterally)). The infundibular stalk was excluded while the bright posterior pituitary was included. All images were tranced manually by a trained rater who was blind to the participants’ group assignment. In a random subset of 24 cases, both the inter-rater reliability (intraclass correlation coefficient r=0.916, p<0.001) and the intra-rater reliability (intraclass correlation coefficient r=0.924 p<0.001) were high. We conducted MANCOVA with gender, and whole brain volumes (WBV) as covariates to compare the PV among the groups.ResultsWe found no significant differences in gender ratio, age, and WBV (p>0.05) among the three groups, but patients with first-episode schizophrenia showed shorter length of education than healthy controls (p<0.001). As expected, we found that male participants in general (Mean ± SD: 486.85 ± 100.24) exhibited a prominently smaller PV than female participants (Mean ± SD: 562.13 ± 102.90) after controlling for WBV (t=25.087, p<0.001). Findings from MANCOVA analysis showed that although first-episode schizophrenia patients (Mean ± SD: 523.81 ± 116.41) and healthy controls (Mean ± SD: 513.17 ± 103.57) showed no significant difference in PV (F=0.581, p=0.447), there was a trend of statistical significance in their non-psychotic first-degree relatives (Mean ± SD: 557.85 ± 93.58) compared with healthy controls (F=3.334, p=0.072). We also found a negative correlation between the duration of treatment and PV in female schizophrenia patients (r=-0.398, p=0.029), whose mean duration of treatment was 4.71 months (SD=2.18 months). No significant correlation was observed in in male patients.DiscussionOur findings found no alteration of PV in first-episode schizophrenia patients but a trend of enlargement was observed in their non-psychotic first-degree relatives. Moreover, female schizophrenia patients with longer duration of treatment exhibited smaller PV. These findings suggested that the enlarged PV might be an early detection signal for individuals with potentially high risk of developing into schizophrenia, and such an enlargement of PV might be responsive to antipsychotic medications.

The anatomic variations and surgical windows among optic chiasm/nerves and carotid arteries in the sellar region play a role in choosing the best surgical approaches: A Cadaveric study

ObjectiveUnderstanding the relationship between the carotid artery, optic nerve and the anterior clinoid process is the basis of surgical approaches performed in the subchiasmal region. The location of the optic chiasm, the length of the optic nerves, and the distance and angle between the optic nerves determine the route of surgical approaches. We have determined the types of optic chiasm to study the relationship between vascular and neural structures in this region. Materials and methodsThirty autopsy specimens were investigated at the Bursa Forensic Medicine Institute for optic chiasm types and the relationship between the neural and vascular anatomical structures of the sellar–parasellar and subchiasmal region was examined between June 2016 and November 2016. ResultsIn this study, 4 prefix types (13%), 6 postfix types (20%), and 20 central types (67%) of chiasm were defined. Furthermore, we measured this angle between two optic nerves, which indirectly shows the location of chiasm according to the diaphragma sellae, and then detected the mean value of this angle as 87.1±11.6°. The “limit” value to designate a chiasm as prefix was measured in the current study as ≥101.1°. The angle between optic nerves ranged from a mean value of 69.9±3.7° in 6 cases with postfix chiasm, to a mean value of 104.0±2.1° in 4 cases with prefix chiasm and a mean value of 88.8±6.7° in 20 cases with central chiasm. ConclusionIn this study, we showed that the relationship among optic chiasma types, optic nerves and bony and vascular structures around the sellar area was effective at determining the surgical approach to this region.

Clinical study of endoscopic treatment of a sellar pituitary adenomas with sellar diaphragm defect

BackgroundInvasive growth of pituitary macroadenomas to the suprasellar region occurs commonly. Pituitary adenomas show varying growth patterns when the sellar diaphragm is absent, and they are often confused with other common tumors in the sellar region. This article explores the clinical features of suprasellar pituitary adenomas with defects of the sellar diaphragm (SPADSD) and evaluates the efficacy of the endoscopic endonasal approach (EEA) for treatment of such tumors.MethodsWe performed a detailed examination of records from 19 patients collected prior to surgery. After relevant diseases were excluded, the tumor properties were evaluated according to imaging characteristics. Diagnoses were verified using EEA surgery. The concept of SPADSD was put forward. Postoperative recovery was followed to determine whether EEA is suitable for the treatment of such tumors.ResultsIn the 19 patients with SPADSD, we found that the tumors were less stressed on the pituitary, and tumors in the suprasellar region often had irregular shapes. During surgery, we took extended supra-saddle approaches and confirmed that unrestricted growth of the tumor was caused by defects in the diaphragm of the sella turcica to the suprasellar region. Recovery was good after surgery, confirming the efficacy of EEA for treatment of these tumors.ConclusionSPADSD has different clinical features from those of other pituitary tumors and requires careful screening prior to surgery. Endoscopic surgery is the preferred procedure for this type of tumor.

Relationship between craniopharyngioma and the third ventricle floor meninges based on QST classification

Objective To explore the relationship between craniopharyngioma based on QST classification with invovlement of the third ventricle floor and the third ventricle floor meninges and its clinical significance. Methods The clinical data of 17 primary craniopharyngioma patients with involvement of the third ventricle floor (6 cases of Q type, 3 cases of S type and 8 cases of T type) undergoing total tumor resection under neuroendoscopy from January 2018 to October 2019 at Neurosurgery Department of Nanfang Hospital, Southern Medical University were retrospectively analyzed. Tumor tissue samples were taken from all patients during operation. The specimens of the normal sellar region were derived from the fetus (8 cases) of the artificial or spontaneous abortion at Nanfang Hospital of Southern Medical University during the same period. Samples were stained by hematoxylin eosin (HE) and immunofluorescence double staining. The dura was labelled with vimentin antibody, arachnoid with type I collagen antibody, pia with glial fibrillary acidic protein antibody and laminin antibody, adenohypophysis with CK18 antibody and craniopharyngioma with CK5 / 6 antibody. We then observed the meningeal staining of fetal brain tissue and relationship between different QST types of craniopharyngioma tissue and the third ventricle floor meninges. Results The dura mater, arachnoid and pia mater of 8 fetuses were labelled successfully. HE staining and immunofluorescence double staining of craniopharyngioma showed that in type Q tumor (6/6), there were dura mater (diaphragma sellae) between tumor and the third ventricle floor. In type S tumor (3/3), there were arachnoid membrane and pia mater between tumor and the third ventricle floor. There were 3 patterns regarding the relationship between type T tumor and the third ventricle floor: mantle-like relationship, moat-like and mortise-like types. There was pia mater between type T tumor (8/8) and the third ventricle floor, and the pia mater could gradually disappear at the origin point of tumor. Although the tumor could remarkably compress the third ventricle and occupy the space of ventricle, the ependymal layer of the third ventricle remained intact. Conclusions All QST types of craniopharyngioma could involve the third ventricle floor and there are various membrane layers between tumor and the third ventricle floor, which could provide natural interface for safe removal of craniopharyngioma with the third ventricle floor involvement. Key words: Craniopharyngioma; Third ventricle; Sella turcica; Meninges; Pathology

The extended pterional approach for midline anterior skull base meningiomas

Background: Various surgical approaches for the management of midline anterior skull base meningiomas exist in the literature. The main surgeon target is proper selection the appropriate approach that achieves total removal of the lesion without causing morbidity or mortality and facilitates safe effective removal of the tumour.&#x0D; Objectives: To evaluate the role of the extended pterional approach for excision of midline anterior skull base meningiomas as regarding the effectiveness, extent of resection and surgical outcome.&#x0D; Patients and methods: This retrospective study involved 23 cases with midline anterior skull base meningiomas resected through the extended pterional approach. Patients' clinical data, operative notes, imaging studies and clinical follow-up data were analyzed and evaluated.&#x0D; Results: Tumors studied were 9 olfactory groove meningiomas, 8 tuberculum Sellae meningiomas, 4 planum sphenoidale meningiomas and 2 diaphragma sellae meningiomas. Gross total resection tumour excision in 15 cases (64.5%), subtotal excision in 5 cases (21.5%) and partial excision in 3 cases (14%). Complications were diabetes insipidus (2 cases 8.6%), CSF rhinorrhea (3 cases 12.9%) and visual deterioration (3 cases 12.9%). We had two cases of mortality.&#x0D; Conclusion: The extended pterional approach allows safe and effective removal of midline anterior skull base meningiomas. It expands the exposure offered by the classic pterional approach and minimizing the necessity for applying fixed brain retraction with good cosmetic outcome and less approach-related morbidities in comparison with the extensive skull base approaches.

Surgical challenges and outcome of endoscopic endonasal approaches in the management of recurrent pituitary adenomas

Background: Various surgical approaches for the management of midline anterior skull base meningiomas exist in the literature. The main surgeon target is proper selection the appropriate approach that achieves total removal of the lesion without causing morbidity or mortality and facilitates safe effective removal of the tumor.&#x0D; Objectives: To evaluate the role of the extended pterional approach for excision of midline anterior skull base meningiomas as regard the effectiveness, extent of resection and surgical outcome.&#x0D; Patients and methods: This retrospective study involved 23 cases with midline anterior skull base meningiomas resected through the extended pterional approach. Patients' clinical data, operative notes, imaging studies and clinical follow-up data were analyzed and evaluated.&#x0D; Results: Tumors studied were 9 olfactory groove meningiomas, 8 tuberculum Sellae meningiomas, 4 planum sphenoidale meningiomas and 2 diaphragma sellae meningiomas. Gross total resection tumor excision in 15 cases (64.5%), subtotal excision in 5 cases (21.5%) and partial excision in 3 cases (14%). Complications were diabetes insipidus (2 cases 8.6%), CSF rhinorrhea (3 cases 12.9%) and visual deterioration (3 cases 12.9%). We had two cases of mortality.&#x0D; Conclusion: The extended pterional approach allows safe and effective removal of midline anterior skull base meningiomas. It expands the exposure offered by the classic pterional approach and minimizing the necessity for applying fixed brain retraction with good cosmetic outcome and less approach related morbidities in comparison with the extensive skull base approaches.

Bilaminar Chitosan Scaffold for Sellar Floor Repair in Transsphenoidal Surgery.

BackgroundEndoscopic endonasal transsphenoidal surgery (EETS) is a standard technique used to approach sellar tumors. It is relatively safe, minimally invasive and carries a low risk of complications. However, one of the common complications reported with this technique is CSF leakage which causes morbidity, an increase in recovery time and hospital costs. This complication usually occurs from violation of the diaphragma sellae and a defect in the structures of the sellar floor or incomplete repair. In this article we report the first case with the use of a novel bilaminar chitosan scaffold which can be potentially used in the repair of the sellar floor, primarily aiming to the bony part of this structure.Case PresentationAfter a personalized design employing a tissue engineering strategy, we reconstructed the sellar floor in a 65-year-old woman who had undergone EETS for a pituitary adenoma with progressive bilateral visual loss. To repair the bony defect of the sellar floor, we used a novel bilaminar chitosan scaffold. The patient had an unremarkable postoperative course with no evidence of CSF leak. The polymer was well tolerated without toxicity, infection or complications. After 2 years of follow up the patient remains neurologically intact, and in good endocrinological status.ConclusionThis is the first report of the use of this biomaterial and its biocompatibility in a clinical setting for the repair of the sellar floor during EETS. Our experience with chitosan bilaminar scaffold and in several preclinical studies in the literature have demonstrated good biocompatibility and effective bioengineered bone regeneration due to its excellent osteoconductive properties, this study pretends to be one landmark for further clinical research and larger case series with the use of this personalized tissue engineering materials in order to see they real efficacy to increase the surgeon armamentarium.

A Simple Onlay Sellar Reconstruction Does Not Increase the Risk of Postoperative Cerebrospinal Fluid Leak in Well-Selected Patients.

Objective A variety of endonasal sellar repair techniques have been described; many of which are complex, expensive, and carry potential morbidity but are felt to be necessary to prevent postoperative cerebrospinal fluid (CSF) leaks. We propose an effective, technically simple repair for select sellar defects utilizing an onlay of regenerated oxidized cellulose. Design Retrospective review of patients from a single neurosurgeon who underwent endoscopic transsphenoidal surgery for pituitary adenoma and sellar reconstruction with only an onlay of regenerated oxidized cellulose. Patients were selected for this repair technique based on the absence of: (1) intraoperative identification of a CSF leak, (2) patulous diaphragm (expanded diaphragm sella herniating to or through sellar floor defect), and (3) other prohibiting comorbidities. Setting The present study was conducted at a tertiary care center. Participants In this study, pituitary adenoma patients were the participants. Outcome Measures Main outcome measure of the study is postoperative CSF leak. Results A total of 172 patients were identified. Of these, 153 were initial resections of pituitary adenomas. Gross total resection was achieved in 142 (82.6%) cases. Average tumor size was 2.2 ± 1.1 cm. Average tumor volume was 10.4 ± 19.8 cm 3 . No patients had intraoperative CSF leaks. All cases were repaired with only an onlay of regenerated oxidized cellulose. There were two postoperative CSF leaks (1.16%). Pre and postoperative SNOT-22 scores were 12.9 ± 11.9 and 14.3 ± 14.9 ( p = 0.796), respectively. Conclusion The use of an onlay of regenerated oxidized cellulose alone is an effective repair technique for select sellar defects. This technique does not result in increased postoperative CSF leak rates and avoids the higher relative cost and potential morbidity associated with more complex, multilayered closures.

Importance of neuroimaging in normal tension glaucoma.

Primary empty sella syndrome (PESS) is caused by an increase in the cerebrospinal fluid (CSF) pressure or a defect in the diaphragma sellae, where the pituitary gland is absent or present as a thin membrane.[1] Optic nerve examination and visual field analysis show glaucomatous changes with normal intraocular pressures (IOPs). A 51-year-old male weighing 65 kg presented with gradual progressive painless diminution of vision in both eyes for 1 year with no significant medical or other histories. Best-corrected visual acuity (BCVA) oculus dexter (OD) was counting fingers near face and oculus sinister (OS) was 6/18. Intraocular pressures (IOPs) were normal. A relative afferent pupillary defect in the right eye (RE) was found. Color vision was defective. Gonioscopy revealed open angles in both eyes. Pachymetry was in the normal range. Fundus examination OD revealed a 0.7-cup disc ratio and in OS 0.8-cup disc ratio, with both eyes showing bayonetting, baring of circumlinear vessels, and nasalization of blood vessels, with rim pallor more than cupping suggesting neurophthalmic cause [Fig. 1].Figure 1: Fundus photographs showing advanced optic disc changes with rim pallor in RE and LETwo hourly diurnal fluctuations ranged normal. Visual field examination showed severe generalized depression, tubular field and absence of split fixation in the left eye (LE) [Fig. 2].Figure 2: LE visual field on octopus perimetry G program and M programAll systemic investigations were within normal limits. Magnetic resonance imaging revealed an empty sella [Fig. 3] and venography was non-significant.Figure 3: MRI of the brain and both orbitsNormal tension glaucoma (NTG) is a diagnosis made after excluding causes of burnout glaucoma and previous episodes of acute hemodynamic disturbances.[2] In PESS, nerve fibers in optic chiasm are perfused from the posterior communicating arteries, which pass round the infundibulum above the pituitary gland. If any mechanical changes occur near the pituitary or sella turcica, the arachnoid may be drawn inferiorly simultaneously pulling the optic chiasm and perfusion vessels downward with resultant optic nerve ischemic changes.[3] We need to remember this association between empty sella, NTG and resultant visual loss.[4] Hence, it becomes necessary to include neuroimaging as an added diagnostic tool in our armamentarium for NTG to avoid diagnostic delay and prevent visual disability. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

Anatomic and histologic features of diaphragma sellae that effects the suprasellar extension

This study aimed to determine the anatomical and histological features of diaphragma sellae that affect the suprasellar extension of intrasellar tumours. Twenty-four fresh adult cadavers were dissected for the study. Diaphragma sellae and pituitary capsules with sellar structures were resected. The diaphragma sellae was anatomically reviewed in detail. Immunohistochemical staining was performed for collagen types I, II, III, and IV. We examined the suprasellar growth of 13 sellar tumours extending superiorly through the diaphragma sellae by performing a series of 2704 endoscopic transnasal operations to analyse the anatomic and histologic results of the study. The diameter of the foramen of diaphragma sellae varied between specimens. Of 24 specimens, the diaphragma sellae in five (21%) had a tight-type foramen and those in 19 (79%) were more spacious. An increased expression of collagen types I and IV was observed in the pituitary capsule and the diaphragma sellae. In this clinical series, we observed that all types of sellar tumours could expand through the foramen. We observed radiologically and intraoperatively that the diaphragma sellae was displaced laterally and formed a dome in two cases with an adenoma extending to the suprasellar area. Two types of suprasellar extension through the diaphragma sellae are possible: 1) The collagen structure of diaphragma sellae can be destroyed by invasive tumours; 2) The morphology of the foramen of the diaphragma sellae facilitates suprasellar tumoural extension. All sellar tumours, including non-invasive cystic tumours, may invade the suprasellar area by expanding through the foramen of the diaphragma sellae.

Primary sellar melanocytoma: pathological, clinical and treatment review.

Sellar melanocytomas represent a small subgroup of primary melanocytic tumors. They arise from melanocytes located in the meningeal lining of the sellar floor or in the diaphragma sellae and this location is very uncommon. Usually, sellar melanocytomas are benign and slow-growing tumors with a high likelihood of recurrence. To our knowledge, due to the rarity of this condition, there are no guidelines regarding their diagnosis and treatment in the medical literature to date. We have developed a narrative review, analyzing the available studies regarding primary sellar melanocytomas reported in the medical literature. We have found ten papers on this topic and all of them are case reports. In all patients, tumor diagnosis was performed after the occurrence of neurological symptoms, in particular progressive visual loss or endocrinological disorders. The diagnosis is difficult, and it requires several preoperative and postoperative investigations, but histological examination is crucial. Transsphenoidal surgery is the first-choice treatment. In case of tumor's recurrence or regrowth, the role of radiation therapy and chemotherapy is not entirely clear.

The anatomic variations and surgical windows among optic chiasm/nerves and carotid arteries in the sellar region play a role in choosing the best surgical approaches: A Cadaveric study.

Understanding the relationship between the carotid artery, optic nerve and the anterior clinoid process is the basis of surgical approaches performed in the subchiasmal region. The location of the optic chiasm, the length of the optic nerves, and the distance and angle between the optic nerves determine the route of surgical approaches. We have determined the types of optic chiasm to study the relationship between vascular and neural structures in this region. Thirty autopsy specimens were investigated at the Bursa Forensic Medicine Institute for optic chiasm types and the relationship between the neural and vascular anatomical structures of the sellar-parasellar and subchiasmal region was examined between June 2016 and November 2016. In this study, 4 prefix types (13%), 6 postfix types (20%), and 20 central types (67%) of chiasm were defined. Furthermore, we measured this angle between two optic nerves, which indirectly shows the location of chiasm according to the diaphragma sellae, and then detected the mean value of this angle as 87.1±11.6°. The "limit" value to designate a chiasm as prefix was measured in the current study as ≥101.1°. The angle between optic nerves ranged from a mean value of 69.9±3.7° in 6 cases with postfix chiasm, to a mean value of 104.0±2.1° in 4 cases with prefix chiasm and a mean value of 88.8±6.7° in 20 cases with central chiasm. In this study, we showed that the relationship among optic chiasma types, optic nerves and bony and vascular structures around the sellar area was effective at determining the surgical approach to this region.

Tentorium Cerebelli: Muscles, Ligaments, and Dura Mater, Part 1.

The tentorium cerebelli is an integral part of the reciprocal tension membranes that divide some brain areas: the falx cerebri, the falx cerebelli, and the diaphragma sellae. The article is divided into two parts. The first part reviews the anatomy of the tentorium cerebelli, the dura mater, and the ligaments and cervical muscles connected to the tentorium. The tentorial area may be subject to trauma or surgery and knowledge of anatomy and existing relationships is essential to better understand the clinical picture. The second part reviews the systemic relationships of the tentorium cerebelli. The neurological anatomical information, which links the tentorium to the central and peripheral nervous systems, venous brain drainage. The tentorium is not just a body segment, but a systemic communication tool.

Endoscopic reconstruction of large anterior skull base defects with opening of the sellar diaphragm. Experience at a tertiary level university hospital.

The indications for expanded endoscopic transnasal approaches continue to increase, with more complex skull base defects needing to be repaired. This study reviews the management of large anterior skull base defects with opening of the sellar diaphragm. A prospective analysis of endonasal endoscopic surgery carried out at Son Espases University Hospital between January 2013 and December 2018 was performed. The analysis included only the cases with a significative intra-operative cerebrospinal fluid leak. In all cases, reconstruction was performed by combining the gasket seal technique with a pedicled mucosal endonasal flap. Twenty-eight patients were included. The mucoperiosteal nasoseptal flap, the lateral wall flap and the middle turbinate flap were used in 13, 8 and 7 patients, respectively, combined with the gasket seal technique. One case of post-operative cerebrospinal fluid leak was observed (3.57 per cent). The combination of a gasket seal with an endonasal mucosal flap is an excellent technique for repairing large anterior skull base defects.