Transsphenoidal Surgery For Pituitary Macroadenoma Research Articles

Cerebral vasospasm following subarachnoid hemorrhage: a rare complication after transsphenoidal surgery for pituitary macroadenoma.

Postoperative (PO) complications after transsphenoidal surgery (TSS) are rare when performed in pituitary referral centers. Partial hypopituitarism is more frequent and somewhat expected. Meningitis, cerebrospinal fluid leaks, and visual deficits are unusual. Cerebrovascular complications, including cerebral vasospasm are rare, usually under-appreciated and not mentioned to the patient prior to the surgery. This is a report of a 51-year-old male with a non-functioning pituitary macroadenoma presenting with partial hypopituitarism and visual field loss. The patient was submitted to an uneventful TSS. On the first PO day, he developed a left palpebral ptosis with unequal pupils and impaired consciousness (12 points on Glasgow Coma Scale). CT scan revealed a perimesencephalic subarachnoid hemorrhage (SAH) grade 1 according to the modified Fisher scale. High-dose dexamethasone (16 mg/day) was initiated and the patient became more alert (Glasgow 14). On the fifth PO day, due to progression of the neurological deficits (left III, IV, and VI cranial nerves palsy, ataxia, dysdiadochokinesia, right dysmetria, and dysarthria), a magnetic resonance angiography was obtained and revealed a recent mesencephalic infarct without evident vasospasm. Nevertheless, nimodipine 60 mg 4/4 h was initiated. No improvement was seen after 3 days of treatment. The patient was discharged and put on rehabilitation, returning to normal gait and balance after 7 months. This, therefore, is a case of an unexpected mesencephalic infarct probably due to vasospasm induced by minor SAH. Although exceptionally rare, informing the patient about this event prior to TSS is important due to its significant neurological impact. More data are needed considering preventive treatment with nimodipine as soon as SAH is detected after TSS and whether it would improve neurological outcomes. Whenever neurological deficits arise after transsphenoidal surgery (TSS), systemic infection, meningitis, electrolyte imbalance, and evident hemorrhage must be promptly investigated. Although rare, cerebral vasospasm (CVS) after TSS is associated with high morbidity and high mortality rates. Vigilance for vasospasm is necessary for patients undergoing TSS for pituitary adenoma, especially those with significant suprasellar extension. Informing this event to the patient prior to TSS is essential due to its significant morbidity and mortality. Post-TSS subarachnoid hemorrhage and hemiparesis may be important clues indicating CVS and infarction. There is limited evidence in the literature regarding post-TSS CVS surveillance and treatment strategies which could have an impact on clinical decisions.

Arachnoid Remodeling by Clipping Technique Facilitates Surgical Maneuverability during Transsphenoidal Surgery for Pituitary Macroadenoma.

ObjectivePituitary adenomas frequently extend into the suprasellar space. After a suprasellar tumor is removed, the superiorly extended arachnoid becomes redundant and sinks down into the intrasellar space which often hiders visualization and accessibility to the hidden space behind the evaginated arachnoid. We introduced arachnoid remodeling by clipping technique, and evaluated its usefulness and safety during TSS. MethodsTotal 223 patients who underwent arachnoid remodeling with our new clipping technique were included. Redundant arachnoid was clipped along the dural edge with multiple 2.6-mm titanium clips until the redundant arachnoid membrane no longer blocked the surgical route. To check for possible deterioration of hormonal function by this technique, we assessed anterior pituitary function of 166 patients who underwent arachnoid remodeling by clipping and compared this with those of other 429 control patients. ResultsOur technique greatly enhanced the accessibility and visualization of intrasellar and parasellar spaces, both of which are generally hindered by redundant arachnoid during transsphenoidal surgery (TSS). We found no difference in anterior pituitary function between a clip-assisted arachnoid remodeling group and the control group, implying that this technique does not result in hypopituitarism. ConclusionDuring TSS for pituitary adenomas with suprasellar extension, arachnoid remodeling by clipping technique is very useful and convenient for the management of the redundant arachnoid membrane to enhance visualization and surgical accessibility.

Changes in the peripapillary and subfoveal choroidal vascularity index after transsphenoidal surgery for pituitary macroadenoma.

To investigate the changes in peripapillary and subfoveal choroidal vascular indexes (CVI) before and after pituitary macroadenoma surgery by using a binarization method. In this cross-sectional study, we examined 17 eyes in 9 patients with pituitary macroadenomas who had undergone transsphenoidal pituitary surgery due to chiasmal compression. We also compiled data from 17of in 17 healthy subjects. ImageJ 1.51 software processing (National Institutes of Health, Bethesda, Maryland, USA) was used for binarization of optical coherence tomography scans. The CVI was computed as the ratio of luminal area to total choroidal areal. The CVI, OCT and VF parameters were analyzed in One-Way Repeated Measures ANOVA to determine significant changes in measurements during the postoperative course. The mean peripapillaryinferior and temporal quadrant CVIs weresignificantly lower in the eyes of patients with pituitary macroadenoma compared to controls (46.0 ± 0.03 versus. 42.8 ± 0.04, p = 0.02; 45.8 ± 0.03 Versus. 42.3 ± 0.04, p = 0.02). In repeated measure analysis, there was a significant effect of transsphenoidal microscobic pituitary surgery on peripapillary inferior quadrant CVI and BCVA, F(1.3, 21.5) = 6.62, p = 0.01 and F (1.8, 29.7) = 7.8, p < 0.005, respectively. This study suggests that PMa with chiasmal compression may lead to significant changes in the peripapillary CVI. Pituitary surgery had a favorable significant effect on peripapillary choroidal vascular network and BCVA. Furthermore, optical coherence tomography is a helpful technique for quantifying the alterations of peripapillary CVI during the preoperative and postoperative course.

Assessment of magnetic resonance imaging criteria for the diagnosis of cavernous sinus invasion by pituitary tumors

Cavernous sinus invasion (CSI) by pituitary tumors is associated with subtotal resection and persistent endocrinopathy. The Knosp classification is a magnetic resonance imaging (MRI) tool used to define CSI in the 2017 World Health Organization Classification. However, alternative criteria may have superior diagnostic performance. This study aimed to assess the diagnostic performance of four MRI criteria, using a combination of endoscopy and day 1 MRI as the reference standard for CSI. A cross-sectional study was conducted including patients treated with endoscopic endonasal transsphenoidal surgery for pituitary macroadenomas, recruited from a tertiary pituitary multidisciplinary center in Sydney, Australia between September 2013, and February 2021. The diagnostic performances of four MRI criteria were assessed: the Knosp criteria, percentage encasement of the internal carotid (PEICA), venous compartment obliteration (VCO), and the Fernandez-Miranda classification. Reference CSI was defined using a combination of intraoperative endoscopy and day 1 MRI. A total of 210 cavernous sinuses (105 patients), were analyzed, (51.7 ± 16.3yrs, 43% female), of which 18% had CSI. CSI was best diagnosed by Knosp ≥ 2 (63% sensitivity and 89% specificity), PEICA ≥ 28% (84% sensitivity and 77% specificity) and VCO of ≥ 3 compartments (65% sensitivity and 89% specificity). CSI was unlikely if any of the following signs were present: Knosp < 1, PEICA < 28%, preservation of the medial or superior compartments or sparing of the superior Fernandez-Miranda compartment (negative predictive value 95%, 95%, 94%, 91% and 92% respectively). In conclusion, alternatives to the Knops criteria including PEICA and VCO can aid CSI diagnosis.

Prevention of Intra-Operative Cerebrospinal Fluid Leaks by Lumbar Cerebrospinal Fluid Drainage during Endoscopic Endonasal Trans- Sphenoidal Surgery for Pituitary Macroadenomas

Aim and Objective: Postoperative cerebrospinal fluid leak is a recognized complication of endoscopic endonasal trans- sphenoidal surgery for pituitary macroadenomas. In this study we assess the utility of prophylactic use of lumbar drain in preventing intra-operative cerebrospinal fluid leakage during endscopic endonasal transsphenoidal surgery for pituitary macroadenoma which will ultimately reduce the rate of persistent post-operative cerebrospinal fluid leakage.&#x0D; Materials and Methods: 34 patients who underwent endscopic endonasal transsphenoidal surgery for pituitary macroadenoma were dividedd into two groups by non-probability convenient sampling technique. In one group of which lumbar subarachnoid drain were given just before induction of anesthesia named LD Group and another group went through conventional method without giving lumbar drain named No LD Group. In all patients of LD Group 20-30 ml of CSF was drawn through lumbar drain before giving dural incision. Valsalva maneuver was used in each group to identify intraoperative CSF leaks at the end of definitive surgery before repairing the sellar floor.Zero degree rigid endoscope was used in all cases. Intraoperative CSF leak was categorized as ‘Yes’ or ‘No’ which was decided by surgeon.Lumbar drains were removed within 24 hours of operation in 16 patients of LD Group and in case 1,who developed intraoperative CSF leak, lumbar drain was removed later.&#x0D; Results: Thirty four patients were eligible for inclusion, of which 17 were assigned to the LD Group and 17 to the no LD Group. There were no statistically significant differences in patient demographics, tumor pathology, or radiology between the two groups. In LD Group intraoperative CSF leak occurred in 1(5.9%) patient and leak did not occur in 16(94.1%) patients, in No LD Group intraoperative CSF leak occurred in 14(82.4%) patients and leak did not occur in 3(17.6%) patients. Intraoperative CSF drainage significantly reduced the incidence of intraoperative CSF leaks from 82.4% in the No LD group to 5.9% in the LD group (P &lt; 0.001). There were no catheter related complications.&#x0D; Conclusion: Intraoperative CSF drainage significantly reduces the incidence of intraoperative CSF leakage in patients undergoing endoscopic endonasal transsphenoidal surgery for pituitary macroadenomas.&#x0D; Bang. J Neurosurgery 2020; 10(1): 52-56

Endoscopic Endonasal Transsphenoidal Surgery for Pituitary Macroadenoma as Minimal Invasive Approach: Case Report

Background: pituitary tumor accounted for 15% of benign intracranial tumors. Clinical symptoms found in the form of visual disturbances, and hormonal manifestations, surgery is one of the main managements. Endoscopic endonasal transsphenoidal surgery (EETS) is a minimally invasive approach for this case. The advantages of EETS is better efficacy than traditional technique, and shorter hospital stays, less mean blood loss, and earlier return to daily activities. Case: we reported a rare example of a male patient aged 37 years old with the main clinical features were visual disturbances, sexual malfunction and bitemporal hemianopsia on physical examination. Magnetic resonance imaging (MRI) showed macroadenoma pituitary, the size 2.41 x 2.98 x 3.20 cm. We explained about minimally invasive surgery such as EETS and the patient was agreed to performed EETS. Conclusion: endoscopic endonasal transsphenoidal surgery is a minimally invasive technique for tumor pituitary cases and safe when compared to traditional medicine.

Cabergoline-Induced Pneumocephalus Following Treatment for Giant Invasive Macroprolactinoma Presenting With Spontaneous Cerebrospinal Fluid Rhinorrhea

Cerebrospinal fluid (CSF) rhinorrhea is rarely reported as the first presenting feature of giant invasive macroprolactinomas. Cerebrospinal fluid rhinorrhea is usually reported as a complication of trauma, neurosurgical, and skull-based procedures (such as pituitary surgery or radiations), and less frequently after medical treatment with dopamine agonists (DAs) for macroprolactinomas. This phenomenon results from fistula creation that communicates between the subarachnoid space and the nasal cavity. Meanwhile, pneumocephalus is another well-recognized complication after transsphenoidal surgery for pituitary macroadenomas. This entity may present with nausea, vomiting, headache, dizziness, and more seriously with seizures and/or a decreased level of consciousness if tension pneumocephalus develops. Case reports about the occurrence of spontaneous pneumocephalus after medical treatment with DAs without prior surgical interventions are scarce in the literature. Our index case is a young man who was recently diagnosed with a giant invasive prolactin-secreting pituitary macroadenoma with skull base destruction. A few months before this diagnosis, he presented with spontaneous CSF rhinorrhea with no history of previous medical or surgical treatment. In this case report, we report an uncommon presentation for giant invasive macroprolactinoma with a CSF leak treated with cabergoline that was subsequently complicated by meningitis and pneumocephalus. This is a very rare complication of cabergoline therapy, which occurred approximately 1 month after treatment initiation.

Role of High-Resolution Dynamic Contrast-Enhanced MRI with Golden-Angle Radial Sparse Parallel Reconstruction to Identify the Normal Pituitary Gland in Patients with Macroadenomas.

Preoperative localization of the pituitary gland with imaging in patients with macroadenomas has been inadequately explored. The pituitary gland enhancing more avidly than a macroadenoma has been described in the literature. Taking advantage of this differential enhancement pattern, our aim was to evaluate the role of high-resolution dynamic MR imaging with golden-angle radial sparse parallel reconstruction in localizing the pituitary gland in patients undergoing trans-sphenoidal resection of a macroadenoma. A retrospective study was performed in 17 patients who underwent trans-sphenoidal surgery for pituitary macroadenoma. Radial volumetric interpolated brain examination sequences with golden-angle radial sparse parallel technique were obtained. Using an ROI-based method to obtain signal-time curves and permeability measures, 3 separate readers identified the normal pituitary gland distinct from the macroadenoma. The readers' localizations were then compared with the intraoperative location of the gland. Statistical analyses were performed to assess the interobserver agreement and correlation with operative findings. The normal pituitary gland was found to have steeper enhancement-time curves as well as higher peak enhancement values compared with the macroadenoma (P < .001). Interobserver agreement was almost perfect in all 3 planes (κ = 0.89). In the 14 cases in which the gland was clearly identified intraoperatively, the correlation between the readers' localization and the true location derived from surgery was also nearly perfect (κ = 0.95). This study confirms our ability to consistently and accurately identify the normal pituitary gland in patients with macroadenomas with the golden-angle radial sparse parallel technique with quantitative permeability measurements and enhancement-time curves.

A Benchmark for Preservation of Normal Pituitary Function After Endoscopic Transsphenoidal Surgery for Pituitary Macroadenomas

We report a contemporary consecutive series of 80 patients operated on for benign pituitary macroadenomas, followed endocrinologically for at least 3months postoperatively. These patients were systematically evaluated preoperatively by high-resolution magnetic resonance imaging designed to detect the position of normal gland relative to the lesion. The rate of preservation of normal pituitary was critically analyzed using this strategy combined with endoscopic transsphenoidal resection. This is a retrospective review of 46 women and 34 men with mean postoperative follow-up of 14 months (range, 3-30 months). The lesions encountered consisted of 80 pituitary macroadenomas (55 nonfunctioning, 18 acromegaly, 5 prolactinoma, 1 Cushing, one thyroid-stimulating hormone). Pituitary endocrine status was determined preoperatively and at most recent follow-up, and categorized as normal or impaired, based on laboratory studies showing new hormone deficiency or the need for pituitary hormone replacement therapy. Fifty-three patients (66.3%) had normal endocrine function preoperatively; 3 (5.7%) had loss of function postoperatively (1 transient). Twenty-seven patients (33.8%) had impaired function preoperatively; postoperatively 20 (74.1%) were unchanged, and 5 (18.5%) were worse; 2(7.4%) recovered lost pituitary function. Of 80 patients undergoing resection, 5 (6.3%) had worsened pituitary function postoperatively. Patients with recurrent lesions (n= 5, 6.3%) and those presenting with pituitary tumor apoplexy (n= 5, 6.3%) were more likely to become further impaired. Other endocrine sequelae included 2 patients with permanent postoperative diabetes insipidus and 3 with transient symptomatic syndrome of inappropriate secretion of antidiuretic hormone. The preservation and restoration of hormonal function are essential to assessing the outcome of surgery and to the patient's quality of life. Careful analysis of the anatomy of the pituitary lesions and their effect on the anatomy and physiology of the pituitary gland are crucial to success and allow modern technological advances to provide fewer complications of therapy and improved outcomes for our patients. The benchmarks provided in this article are a stimulus for even better results in the future as we take advantage of technical and conceptual advances and the benefits of multidisciplinary collaboration.

A clinical reaserch of endoscopic endonasal transsphenoidal surgery for pituitary macroadenoma

Objective:To share our exprience with the surgical management of pituitary macroadenoma and giant adenoma excision technique through the endoscopic transsphenoidal approach. Method:A retrospective analysis data of 27 patients with pituitary macroadenoma and giant adenoma surgery methods, postoperative complications and follow-up results. Result:All patients have no postoperative complications happened such as: nasal bleeding, intracranial hemorrhage, cerebrospinal fluid leak, blood sugar increased. Tumors invaded cavernous sinus in 5 cases, surrounded internal carotid artery in 2 cases, compressed optic chiasma in 7 cases and encroached optic nerve in 1 case. Postoperative vision decline occurred in 2 cases: 1 case recovered to the preoperative level after being taken out nasal stuffing and with conservative treatment, 1 case (preoperative visual acuity 0.1) restored light perception after conservative treatment. Postoperative diabetes insipidus occurred in 4 cases, and recovered in next week with corresponding therapy. Conclusion:Endoscopic endonasal transsphenoidal surgery is a safe and effective surgical technique.

The utility of high-resolution intraoperative MRI in endoscopic transsphenoidal surgery for pituitary macroadenomas: early experience in the Advanced Multimodality Image Guided Operating suite

Endoscopic skull base surgery has become increasingly popular among the skull base surgery community, with improved illumination and angled visualization potentially improving tumor resection rates. Intraoperative MRI (iMRI) is used to detect residual disease during the course of the resection. This study is an investigation of the utility of 3-T iMRI in combination with transnasal endoscopy with regard to gross-total resection (GTR) of pituitary macroadenomas. The authors retrospectively reviewed all endoscopic transsphenoidal operations performed in the Advanced Multimodality Image Guided Operating (AMIGO) suite from November 2011 to December 2014. Inclusion criteria were patients harboring presumed pituitary macroadenomas with optic nerve or chiasmal compression and visual loss, operated on by a single surgeon. Of the 27 patients who underwent transsphenoidal resection in the AMIGO suite, 20 patients met the inclusion criteria. The endoscope alone, without the use of iMRI, would have correctly predicted extent of resection in 13 (65%) of 20 cases. Gross-total resection was achieved in 12 patients (60%) prior to MRI. Intraoperative MRI helped convert 1 STR and 4 NTRs to GTRs, increasing the number of GTRs from 12 (60%) to 16 (80%). Despite advances in visualization provided by the endoscope, the incidence of residual disease can potentially place the patient at risk for additional surgery. The authors found that iMRI can be useful in detecting unexpected residual tumor. The cost-effectiveness of this tool is yet to be determined.

The Utility of High Resolution Intraoperative MRI in Endoscopic Transsphenoidal Surgery for Pituitary Macroadenomas: Early Experience in the Advanced Multimodality Image-Guided Operating (AMIGO) Suite

Introduction: Maximal extent of resection for pituitary macroadenomas achieves optimal neural decompression, the best chance at endocrine cure, and lowers the rate of recurrence. Many studies have demonstrated the utility of low resolution intraoperative MRI (iMRI) during microscopic transsphenoidal surgery in uncovering residual tumor. Few studies, however, have investigated the utility of high-resolution iMRI in combination with endoscopy with regard to gross total resection. The Advanced Multimodality Image Guided Operating (AMIGO) suite at the Brigham and Women’s Hospital harnesses the power of a high-resolution 3-T iMRI and integrated neuronavigation. We reviewed the experience of our initial 12 cases of pituitary macroadenomas operated on by an endoscopic transsphenoidal approach in the AMIGO suite.

Fatal rhinocerebral mucormycosis with intracavernous carotid aneurysm and thrombosis: a late complication of transsphenoidal surgery?

Mucormycosis is a rare opportunistic fungal infection. Rhinocerebral form of the disease mainly affects diabetic or immunocompromised patients. Mucormycosis have specific tropism for blood vessels leading to mucorthrombosis and less often to mycotic aneurysms. We report on a patient initially presenting with a severe sphenoid sinusopathy, who progressively evolved to cavernous sinus syndrome, internal carotid aneurysm followed by spontaneous thrombosis, chronic meningitis and ultimately fatal hypertensive hydrocephalus. Necropsy revealed a purulent infiltrate containing thin-walled, aseptate, right-angle branching, hyphae consistent with mucormycosis. His only relevant previous medical history was a transsphenoidal surgery for pituitary macroadenoma 21years before. We hypothesize that post-surgical mucosal changes in the sphenoid sinus have been a favoring factor for delayed and invasive mucor infection.

The Suture-Pull as a Refinement of the Gasket Implant Technique for Reconstruction after Endoscopic Skull Base Surgery

Introduction: Adequate reconstruction of the skull base is the key to avoiding cerebrospinal fluid (CSF) leak following endonasal skull base surgery. The use of an endocranial ”gasket” plug has been reported for this and is used in our institution. We present a simple refinement of the ”gasket” technique using commonly available materials that helps ensure proper size and positioning of the gasket by applying stress on a suture attached on the center of the gasket implant. Materials and Methods: We report a case of massive CSF leak following endonasal transsphenoidal surgery for pituitary macroadenoma. The skull base was reconstructed in a multi-layered fashion with fascia lata and bony buttress reinforced with a vascularized nasoseptal flap. In order to avoid implant slippage from too-small size or malpositioning, we performed a ”stress test” using traction applied to a suture attached to the center of the implant (Medpor®), which allowed us to confirm intraoperatively that the buttress was positioned securely. Results: The patient did well without recurrence of CSF leak. At two-year follow-up, there has been no recurrence of CSF leak or occurrence local complications. We have not verified whether bony regrowth into the implant has occurred. Conclusion: The suture-pull refinement of the gasket implant technique is a simple, inexpensive and low risk method to assure secure endocranial positioning over the skull base defect, and may prevent CSF leak resulting from too-small sizing or buttress malpositioning.

Maximizing the extent of tumor resection during transsphenoidal surgery for pituitary macroadenomas: can endoscopy replace intraoperative magnetic resonance imaging?

Endoscopic approaches to pituitary tumors have become an effective alternative to traditional microscopic transsphenoidal approaches. Despite a proven potential to decrease unexpected residual tumor, intraoperative MR (iMR) imaging is infrequently used even in the few operating environments in which such technology is available. Its use is prohibitive because of its cost, increased complexity, and longer operative times. The authors assessed the potential of intrasellar endoscopy to replace the need for iMR imaging without sacrificing the maximum extent of resection. In this retrospective study, 27 consecutive patients underwent fully endoscopic resection of pituitary macroadenomas. Intrasellar endoscopy was used to determine the presence of residual tumor within the sella turcica and tumor cavity. Intraoperative MR imaging was used to identify rates of unexpected residual tumor and the need for further tumor resection. Intraoperative estimates of the extent of tumor resection were correct in 23 patients (85%). Of 4 patients with unacceptable tumor residuals, 3 underwent further tumor resection. After iMR imaging, the rate of successful completion of the planned extent of resection increased to 26 patients (96%). Rates of both endocrinopathy reversal and postoperative complications were consistent with previously published results for microscopic and endoscopic resection techniques. The findings in this study provided quantitative evidence that intrasellar endoscopy has significant promise for maximizing the extent of tumor resection and is a useful adjunct to surgical approaches to pituitary tumors, particularly when iMR imaging is unavailable. A larger prospective study on the extent of resection following endoscopic transsphenoidal surgery would strengthen these findings.

Intraoperative MRI during transsphenoidal surgery of pituitary macroadenomas

Objective: To report our experiences with MRI during transsphenoidal surgery for pituitary macroadenomas with specific regards to the extent of resection and the relevance for the further management of these patients.

MRI appearances of the sphenoid sinus at the late follow-up of trans-sphenoidal surgery for pituitary macroadenoma.

We aimed to demonstrate the appearances of the sphenoid sinus on MRI performed later than 2 years post- transsphenoidal surgery (TSS). We retrospectively reviewed 47 patients in whom follow-up MRI scans had been performed at least 2 years post-TSS. We specifically reviewed the clinical and imaging of those patients in whom the sphenoid sinus was filled with signal abnormality or masses were present arising from the sinus roof and classified them as tumour or indeterminate abnormalities on imaging criteria. We documented other clinicoradiological details. Twelve of 47 patients demonstrated sphenoid sinus filling or sinus roof masses and in six of 12 patients it was possible to classify them as tumourous using imaging and clinical criteria. The indeterminate and non-tumourous sphenoid sinus abnormalities most frequently had a T1-weighted signal similar to subsellar tumour and displayed rim enhancement and thus could not be reliably distinguished from tumourous abnormality on the basis of signal or enhancement characteristics. The presence of a well-defined surgical defect in the sella floor was associated with resolution of abnormality on MRI follow-up. We concluded MRI findings of sphenoid sinus filling or sinus roof masses are present in approximately 26% of scans performed longer than 2 years post-TSS. Half of these are of indeterminate origin and follow-up is required to discriminate tumour from non- tumour with certainty. A well-defined surgical defect in the sella floor is, however, suggestive of a non-tumourous abnormality.