Transcranial surgery for pituitary adenomas

The open sella technique for surgical treatment of pituitary macroadenomas: Safety and efficacy in a large clinical series

PURPOSE

To analyse the efficacy and safety of the transsphenoidal microsurgical approach with open sella technique (OST) for the treatment of pituitary adenoma (PA) with suprasellar extension.

METHODS

We retrospectively reviewed 2305 consecutive patients with PA who underwent their first surgery through the transsphenoidal microsurgical approach at our department between 1990 and 2018. Focusing on tumours with suprasellar extension, in particular, grade B, C and D adenomas according to Wilson-Hardy's classification, 376 patients who received the OST surgery were identified. Outcomes and complications were evaluated and compared with those obtained in patients who underwent a standard transsphenoidal approach (TSM).

RESULTS

Two-hundred and sixty-four of 376 patients (70.2%) were found to be suffering from a non-functioning pituitary adenoma, whereas 112 of 376 patients (29.8%) from a hormone-secreting PA. The mean craniocaudal diameter of the tumor was 30.6 ± 0.3 mm (range, 21-75 mm) and 151 patients (40.1%) had a cavernous sinus invasion too. An overall surgical remission rate of 50.3% was achieved in the OST group, whereas the recurrence rate was 10.5%. Patients were followed for a mean period of 68 ± 1.4 months (range, 6-96 months). Less postoperative intrasellar haemorrhages have been recorded in the OST group than the TSM one (1.1% vs. 4.6%, p = 0.02).

CONCLUSIONS

In experienced hands, OST represents an effective and safe treatment strategy for PA with suprasellar extension.

Endoscopic Endonasal Transplanum-Transtuberculum Approach for Pituitary Adenomas/PitNET: 25 Years of Experience

The role of the endoscopic transplanum-transtuberculum approach (ETTA) in the treatment of pituitary adenomas/PitNETs (PAs) is sparsely analyzed in the literature, and its use is still debated in the current practice. The aim of this study was to report our experience with this approach. Our institutional registry was retrospectively reviewed, and patients who underwent ETTA for a PA from 1998 to 2022 were included. Fifty-seven cases were enrolled over a time span of 25 years, corresponding to 2.4% of our entire PA caseload. Radical resection was achieved in 57.9% of cases, with re-do surgery (p = 0.033) and vessel encasement/engulfment (p < 0.001) as predictors of partial resection. CSF leak incidence stood at 8.8%, with higher BMI (p = 0.038) as its only significant predictor. Partial or full improvement of the visual field deficits was achieved in 73.5% of cases. No surgical mortality was observed. According to our results, ETTA for the treatment of PAs is characterized by a satisfactory surgical outcome but with greater morbidity than the conventional endoscopic approach. Therefore, it should be reserved for the few selected cases otherwise unsuitable for the endoscopic trans-sphenoidal route, representing a valid alternative and an effective complementary route for the transcranial approach for these challenging PAs.

Magnetic resonance imaging grading of pituitary macroadenoma – SIPAP classification revisited

Background

Magnetic resonance imaging (MRI) is regarded as the modality of choice in diagnosis of pituitary macroadenomas. Since surgery is the first line therapy for all pituitary adenomas, simple and reproducible MRI classification based on major directions of tumour growth is an essential tool. SIPAP MRI classification for pituitary adenoma describes tumor extension in parasellar, suprasellar, infrasellar, anterior and posterior directions. We, therefore, evaluated reproducibility of SIPAP classification in reporting of pituitary adenomas.

Methods

Forty-nine patients with biopsy-proven pituitary macroadenoma were graded according to SIPAP classification. Data was analyzed using Stata version 15. Interobserver variability was calculated using Cohen’s Kappa. Comparison between grading before and after treatment was performed by Chi-square test. P values < 0.05 were considered statistically significant.

Results

Individual tumour extensions according to SIPAP for pre- and post-operative grading showed significant difference (p-value <0.001), except for anterior extension. For suprasellar extension, 67.3 % patients had pre-operative grade-3 and 63.3 % had post-operative grade-0. For infrasellar extension, 51.0 % had pre-operative grade-2 and 71.4 % had post-operative grade-0. Anterior, posterior and parasellar extensions showed increased frequency in grade-0 in post-operative stage compared to pre-operative. Substantial inter-observer agreement was achieved for Superior, Inferior, Anterior and Posterior extent with all Kappa statistics values above 0.7 (p-value <0.001).

Conclusion

We propose incorporating simple and objective SIPAP classification in routine MR reporting for ideal pituitary tumour delineation, relationship to juxtasellar structures and tumour size, hence facilitating greater success rate in surgical and subsequent clinical management.

Staged surgery for irregular giant pituitary adenomas: A report of two cases

The resection of giant pituitary adenomas is one of the most challenging brain surgeries, especially when the giant pituitary adenomas have an irregular shape or irregular growth position. The purpose of the present study is to propose staged surgery for irregular giant pituitary adenomas through a retrospective analysis of two cases. The cases of two patients with irregular giant pituitary adenomas who underwent staged surgery are retrospectively analyzed. In one case, a 51-year-old male was hospitalized after 2 months of memory loss. Brain MRI showed that the pituitary adenoma was paginated and located in the sellar and right suprasellar regions, with a size of ~6.15×6.11×5.69 cm. In the second case, a 60-year-old male had a history of intermittent vertigo for 10 years and paroxysmal amaurosis for 1 year. Brain MRI showed that the pituitary adenoma grew laterally and eccentrically, and was located in the sellar region, with a size of ~4.35×3.96×3.07 cm. Both patients underwent staged surgery; more specifically, the tumors were totally removed through two-stage surgery. In the first-stage operation, most of the tumor was removed by the microscopic transcranial approach, while in the second-stage operation, the residual tumor was removed by the endoscopic transsphenoidal approach. Both patients recovered well without obvious postoperative complications after staged surgery. There was no recurrence during the follow-up. Staged surgery is characterized by only treating tumors in the visual field and achieving a total tumor resection, which has the advantages of a high tumor resection rate, high safety and fewer postoperative complications. Staged surgery is especially suitable for irregular giant pituitary adenomas with an irregular shape or irregular growth position.

Large Pituitary Adenoma: Strategies to Maximize Volumetric Resection Using Endoscopic Endonasal Approaches and an Analysis of Factors Limiting Resection

BACKGROUND

Large pituitary adenomas (LPAs), which constitute ∼5%-14% of all pituitary adenomas, are considered challenging tumors owing to their locally aggressive behavior, low gross total resection rate, and high prevalence of visual deficits and hypopituitarism. We evaluated the utility of various extended endoscopic endonasal approaches in maximizing the resection of LPAs and studied the factors affecting the extent of surgical resection.

METHODS

A retrospective study of all LPAs (defined as a minimum diameter >3 cm and tumor volume >10 cm3) treated via an endoscopic endonasal approach between January 2015 and December 2020 was performed. The volumetric extent of resection (3-dimensional volumetric analysis software) was correlated with various demographic, tumor-related, pathologic, and immunohistochemical factors and its effects on the clinical outcomes studied.

RESULTS

The present study included 106 patients with LPAs. The mean extent of the resection volume was 79.18 ± 21.75 cm3. The factors that affected the extent of resection included the preoperative tumor volume (P = 0.03) and Knosp grade (P = 0.03). The percentage increase in the extent of resection with the use of 2 endonasal corridors was 10.6% and with 3 corridors was 14%. Visual improvement occurred in 82% of patients, and new-onset persistent hormonal insufficiency occurred in 2.9% of patients. Mortality directly related to surgery occurred in 1.8% of cases.

CONCLUSIONS

Extended endoscopic endonasal approaches can safely and effectively be used for gross total resection of LPAs. However, we found that the preoperative tumor volume and Knosp grade were significant factors affecting the extent of tumor resection. The use of multiple endoscopic endonasal corridors can increase the volumetric extent of resection for LPAs.

Application of “mosiac sign” on T2-WI in predicting the consistency of pituitary neuroendocrine tumors

Purpose

Tumor consistency is important for pituitary neuroendocrine tumors (PitNETs) resection to improve surgical outcomes. In this study, we evaluated the T2-WI of PitNETs and defined a specific T2-WI signaling manifestation, the “Mosaic sign,” to predict tumor consistency and resection of PitNETs.

Design

A retrospective review of MRI and tumor histology of 137 consecutive patients who underwent endoscopic endonasal resection for PitNETs was performed.

Methods

The “Mosaic sign” was defined by the ratio of the tumor itself T2-WI signals, and characterized by multiple intratumor hyperintense dots. The degree of tumor resection was an assessment by postoperative MRI examination. The presence of the “Mosaic sign” was compared with patients' basic information, tumor consistency, tumor pathological staining, and surgical result. To determine whether the presence or absence of “Mosaic sign” could predict tumor consistency and guide surgical resection of tumors.

Results

Statistical analysis showed that the consistency of the tumor and the degree of resection were correlated with the “Mosaic sign”. In the 137 cases of T2-WI, 43 had “Mosaic sign”, 39 cases had soft tumor consistency, and 4 were classified as fibrous, of which 42 were completely resected and 1 was subtotal resected. Of the 94 patients without “Mosaic sign”, the consistency of tumor of 54 cases were classified as soft, the remaining 40 cases were fibrous, 80 cases were completely resected, and 14 cases were subtotal resected. Postoperative cerebrospinal fluid leakage occurred in 1 patient. The number of corticotroph adenomas in the group of “Mosaic sign” was higher, with the statistical difference between the two groups (P = 0.0343).

Conclusions

The presence of the “Mosaic sign” in T2-WI may provide preoperative information for pituitary adenomas consistency and effectively guide surgical approaches.

Transcranial approaches for pituitary adenomas: current indications and clinical and radiological outcomes

Background

The indications of transcranial approaches for pituitary adenomas have declined in the last decades with the widespread performance of endoscopic transsphenoidal approaches.

The aim of the study was to review the current indications of transcranial approaches for pituitary adenomas and to evaluate the clinical and radiological outcome following these approaches.

Patients and methods

This study included 16 patients with fresh, residual, or recurrent pituitary adenomas operated upon by transcranial approaches alone or in combination with transsphenoidal approaches. The indication to perform a transcranial approach was reviewed for each patient. Postoperative clinical outcome and the extent of tumor resection were assessed.

Results

The indications of transcranial approaches were significant parasellar and/or anterior fossa extensions in 6 patients, failed previous transsphenoidal surgery in 3 patients, giant adenoma extending into the third ventricle in 3 patients, dumbbell-shaped adenoma in 2 patients, and doubtful diagnosis in 2 patients. Two patients with invasive giant adenomas were operated upon by a combined approach. There was a single mortality. Permanent complications included visual loss in one patient, third nerve palsy in one patient, hypopituitarism in two patients, and permanent diabetes insipidus in two patients. Gross total resection was achieved in one patient, subtotal resection in seven patients, and partial resection in eight patients.

Conclusion

Transcranial approaches are still needed for some complex pituitary adenomas particularly giant tumors with significant lateral, anterior, or superior extensions, tumors with fibrous consistency particularly after failure of transsphenoidal approach, and dumbbell-shaped tumors with severe constriction at the diaphragm.

Primary Endoscopic Endonasal Management of Giant Pituitary Adenomas: Outcome and Pitfalls from a Large Prospective Multicenter Experience

Simple Summary

Giant pituitary adenomas are highly invasive tumors whose treatment is challenging. Surgery is their management mainstay. However, there is no consensus about the type of approach. Open transcranial, microscopic, and endoscopic trans-sphenoidal approaches have all been employed, alone or in combination. Extended endoscopic endonasal techniques may represent a versatile and safe one-stage approach. Our research aimed at evaluating prospectively their applicability, effectiveness, and safety in a multicenter series, to acquire further evidence toward its use in the treatment of those challenging lesions. Ninety-six patients were recruited and followed-up for 52.4 months on average. Most of them (81.2%) presented with visual deficits and >50% had various degrees of adenohypophysis insufficiency. Resection of at least 75% of initial volume was achieved in all cases, with 98.7% visual improvement, >50% endocrine deficit recovery and a permanent complication rate of 4.2%, indicating extended endoscopic endonasal approaches as a valuable treatment option.

Abstract

Purpose: To evaluate factors influencing clinical and radiological outcome of extended endoscopic endonasal transtuberculum/transplanum approach (EEA-TTP) for giant pituitary adenomas (GPAs). Methods: We recruited prospectively all consecutive GPAs patients undergoing EEA-TTP between 2015 and 2019 in 5 neurosurgical centers. Preoperative clinical and radiologic features, visual and hormonal outcomes, extent of resection (EoR), complications and recurrence rates were recorded and analyzed. Results: Of 1169 patients treated for pituitary adenoma, 96 (8.2%) had GPAs. Seventy-eight (81.2%) patients had visual impairment, 12 (12.5%) had headaches, 3 (3.1%) had drowsiness due to hydrocephalus, and 53 (55.2%) had anterior pituitary insufficiency. EoR was gross or near-total in 46 (47.9%) and subtotal in 50 (52.1%) patients. Incomplete resection was associated with lateral suprasellar, intraventricular and/or cavernous sinus extension and with firm/fibrous consistence. At the last follow-up, all but one patient (77, 98.7%) with visual deficits improved. Headache improved in 8 (88.9%) and anterior pituitary function recovered in 27 (50.9%) patients. Recurrence rate was 16.7%, with 32 months mean recurrence-free survival. Conclusions: EEA-TTP is a valid option for GPAs and seems to provide better outcomes, lower rate of complications and higher EoR compared to one- or multi-stage microscopic, non-extended endoscopic transsphenoidal, and transcranial resections.

Photoacoustic-guided surgery from head to toe [Invited]

Photoacoustic imaging-the combination of optics and acoustics to visualize differences in optical absorption - has recently demonstrated strong viability as a promising method to provide critical guidance of multiple surgeries and procedures. Benefits include its potential to assist with tumor resection, identify hemorrhaged and ablated tissue, visualize metal implants (e.g., needle tips, tool tips, brachytherapy seeds), track catheter tips, and avoid accidental injury to critical subsurface anatomy (e.g., major vessels and nerves hidden by tissue during surgery). These benefits are significant because they reduce surgical error, associated surgery-related complications (e.g., cancer recurrence, paralysis, excessive bleeding), and accidental patient death in the operating room. This invited review covers multiple aspects of the use of photoacoustic imaging to guide both surgical and related non-surgical interventions. Applicable organ systems span structures within the head to contents of the toes, with an eye toward surgical and interventional translation for the benefit of patients and for use in operating rooms and interventional suites worldwide. We additionally include a critical discussion of complete systems and tools needed to maximize the success of surgical and interventional applications of photoacoustic-based technology, spanning light delivery, acoustic detection, and robotic methods. Multiple enabling hardware and software integration components are also discussed, concluding with a summary and future outlook based on the current state of technological developments, recent achievements, and possible new directions.

Transcranial approach as surgical treatment for giant pituitary adenoma during COVID 19 pandemic - What can we learn?: A case report

Introduction

In the COVID 19 pandemic, pituitary surgery is one of challenging surgical treatment, especially the involving transsphenoid approach. It was reported that the aerosolisation and mucosal involvement increase the risk of viral transmission during operation. Therefore, transcranial is a safer surgical approach during COVID-19 pandemic. This study aimed to reported transcranial approach to treat giant pituitary adenoma with aggressive visual disturbance which require urgent surgical management.

Case presentation

We reported a 21-year old male, who required urgent surgery because of progressive visual disturbance due to giant pituitary adenoma. On brain MRI with contrast, it was revealed an extraaxial tumor extending anteriorly over plannum sphenoidal with the greatest diameter was 5.34 cm. Transcranial approach was chosen to resect the tumor. Near total removal of the tumor was achieved without damaging vital neurovascular structure. The visual acuity was improved and no significant postoperative complication. Pathology examination revealed pituitary adenoma.

Conclusion

Transcranial surgery for pituitary adenoma is still an armamentarium in neurosurgical practice, especially in the COVID 19 pandemic to provide safer surgical approach.

Endoscopic Endonasal Approach to Giant Pituitary Adenomas: Surgical Outcomes and Review of the Literature

OBJECTIVE

To present the outcomes of endoscopic endonasal surgery for giant pituitary adenomas and discuss the extent of resection to minimize morbidity and mortality.

METHODS

We retrospectively reviewed medical records of 44 patients with giant pituitary adenomas who underwent endoscopic endonasal surgery. Clinical presentation, laboratory results, imaging studies, clinical outcomes, extent of resection, and complications were collected and analyzed. Factors affecting long-term outcome according to surgical technique were identified and analyzed.

RESULTS

Radical resection (RR) was defined as either gross total resection or near-total resection (90%-100% of the tumor). There were 28 patients (63.6%) who underwent RR, 10 patients (22.7%) who underwent subtotal resection, and 6 patients (13.6%) who underwent partial resection. Visual improvement was achieved in 27 patients (81.8%). Thirteen patients (72.2%) with pituitary dysfunction had improvement in at least 1 preoperative endocrinological dysfunction. RR rates for dumbbell and multilobular tumors were 44.4% and 28.6%, respectively. Surgical complications were observed in 14 (31.8%) patients. Major vascular injury occurred in 3 patients (6.8%). Mean follow-up period was 38.5 months (range, 1-70 months). No patients with RR had recurrence or residual tumor progression. Ten patients (22.7%) received adjuvant radiation therapy after resection. Two patients were reoperated on for tumor regrowth, and 3 patients (including the 2 patients with tumor regrowth) were lost to follow-up.

CONCLUSIONS

Long-term follow-up results and low recurrence rate of tumors indicate that RR is effective to decrease morbidity and mortality.

Transcranial approach for pituitary adenomas - An evaluation of surgical approaches over two decades and factors influencing peri-operative morbidity

PURPOSE

Transcranial surgery(TCS) for pituitary adenoma(PA) is mostly reserved for lesions with widespread extensions. We sought to analyse the intraoperative challenges, morbidity and the factors associated with morbidity of transcranial approaches, in a large series from a tertiary neurosurgical institute.

METHODS

We retrospectively evaluated 137 patients who underwent TCS for PA in our institute. The details of their clinical features, imaging, operative and peri-operative events and complications were collected and analysed. The factors associated with morbidity were evaluated.

RESULTS

The mean age of the cohort was 40.86 ± 13.35 years. 21 (15.3%) patients developed significant post-operative hematoma, out of which 7 patients (5.1%) required re-exploration. Post-operative diabetes insipidus was noted in 45 patients (32.84%), while SIADH was noted in 10 patients (7.35%). Other complications were cranial nerve palsy in 14 patients (10.2%), visual deterioration in 7 patients (5.1%). Neither tumour characteristics nor the choice of approach was associated with occurrence of post op hematoma. SIADH was significantly associated with patients with tumours involving cavernous sinus (p = 0.019) and subfrontal extension (p = 0.031). Patients with post-operative hematoma had significantly higher incidence of post-op DI (57.1% vs 28.7%; p = 0.021), while similar correlation was not noticed with SIADH (4.7 vs 7.8%).

CONCLUSION

TCS plays a distinct, albeit a small role in surgical management of pituitary adenoma. Tumour related or approach related factors are not significantly associated with the incidence of hematoma. Post-operative hematoma significantly influences the incidence of DI. A proper and judicious selection of approach and meticulous surgical technique should result in a reduction in associated morbidity and mortality.

Extended endonasal approaches for pituitary adenomas

Pituitary adenomas with significant extension beyond the sellar boundary, large size, asymmetrical shape and subarachnoid space invasion, although rare, represent a therapeutic challenge. The invasiveness of the tumor itself often limits the potential for complete tumor resection and increases the likelihood of intraoperative or postoperative complications, regardless of the approach. The extended endoscopic endonasal approach has been proposed as a valid alternative to the transcranial route for the treatment of certain pituitary adenomas not suitable to the standard transsphenoidal approach. Thanks to the wide and close up view provided by the endoscope via the appropriate expanded bone removal at the skull base, this technique offers, in an adequate working space, a safe exposure of the tumor and surrounding anatomical structures, at the supra-, para-, and retro-sellar areas. It stands clear that the primary goal of this approach remains the maximum allowed resection with preservation of neurological and endocrine functions. Herein, we debate the extended endoscopic endonasal technique for the treatment of pituitary adenomas, with the aim of underlying its indications, pitfalls, advantages, and limitations.

Simulations and human cadaver head studies to identify optimal acoustic receiver locations for minimally invasive photoacoustic-guided neurosurgery

Real-time intraoperative guidance during minimally invasive neurosurgical procedures (e.g., endonasal transsphenoidal surgery) is often limited to endoscopy and CT-guided image navigation, which can be suboptimal at locating underlying blood vessels and nerves. Accidental damage to these critical structures can have severe surgical complications, including patient blindness and death. Photoacoustic image guidance was previously proposed as a method to prevent accidental injury. While the proposed technique remains promising, the original light delivery and sound reception components of this technology require alterations to make the technique suitable for patient use. This paper presents simulation and experimental studies performed with both an intact human skull (which was cleaned from tissue attachments) and a complete human cadaver head (with contents and surrounding tissue intact) in order to investigate optimal locations for ultrasound probe placement during photoacoustic imaging and to test the feasibility of a modified light delivery design. Volumetric x-ray CT images of the human skull were used to create k-Wave simulations of acoustic wave propagation within this cranial environment. Photoacoustic imaging of the internal carotid artery (ICA) was performed with this same skull. Optical fibers emitting 750 nm light were inserted into the nasal cavity for ICA illumination. The ultrasound probe was placed on three optimal regions identified by simulations: (1) nasal cavity, (2) ocular region, and (3) 1 mm-thick temporal bone (which received 9.2%, 4.7%, and 3.8% of the initial photoacoustic pressure, respectively, in simulations). For these three probe locations, the contrast of the ICA in comparative experimental photoacoustic images was 27 dB, 19 dB, and 12 dB, respectively, with delay-and-sum (DAS) beamforming and laser pulse energies of 3 mJ, 5 mJ, and 4.2 mJ, respectively. Short-lag spatial coherence (SLSC) beamforming improved the contrast of these DAS images by up to 15 dB, enabled visualization of multiple cross-sectional ICA views in a single image, and enabled the use of lower laser energies. Combined simulation and experimental results with the emptied skull and >1 mm-thick temporal bone indicated that the ocular and nasal regions were more optimal probe locations than the temporal ultrasound probe location. Results from both the same skull filled with ovine brains and eyes and the human cadaver head validate the ocular region as an optimal acoustic window for our current system setup, producing high-contrast (i.e., up to 35 dB) DAS and SLSC photoacoustic images within the laser safety limits of a novel, compact light delivery system design that is independent of surgical tools (i.e., a fiber bundle with 6.8 mm outer diameter, 2 mm-diameter optical aperture, and an air gap spacing between the sphenoid bone and fiber tips). These results are promising toward identifying, quantifying, and overcoming major system design barriers to proceed with future patient testing.

Surgical treatment of aggressive pituitary adenomas and pituitary carcinomas

Surgery of aggressive pituitary adenomas and pituitary carcinomas is part of the interdisciplinary management of these difficult to treat tumors. Invasion, giant size and unusual, asymmetric extent of these tumors frequently require modifications or extensions of the standard approaches for transsphenoidal and transcranial surgery. Frequently, only debulking procedures can be performed. In aggressive and hormone secreting adenomas, the remission rates achieved by surgery alone are relatively poor and adjuvant medical treatments or irradiation are needed. Safe resection of as much tumor as possible and symptomatic control is aimed at, rather than remission. Many procedures are required for rapid progression of lesions or recurrences, in order to extend the survival of the patients. Metastases of pituitary carcinomas within the cranial cavity or spine can be attacked. Since they can occur anywhere in the brain or spinal canal they require the entire battery of neurosurgical approaches. Unfortunately, in this group of pituitary tumors, the complication rates are higher than in primary operations of enclosed adenomas. The respective techniques with their facilities and limitations are reviewed in this article.

Surgical Outcomes and Predictors of Visual Function Alterations After Transcranial Surgery for Large-to-Giant Pituitary Adenomas

BACKGROUND

Factors associated with visual outcomes after transcranial surgery for large-to-giant pituitary adenomas have not been fully elucidated.

METHODS

We recruited 37 patients with large-to-giant pituitary adenomas between January 2014 and December 2016 and assessed their tumor characteristics and surgical outcomes. Visual acuity and visual field were evaluated by visual impairment score before and 3-6 months after transcranial surgery. Multivariable logistic regression analysis was applied to show the factors associated with visual outcomes after surgery.

RESULTS

The severity levels of visual impairment before surgery were mild, moderate, severe, and complete in 24.3% (9/37), 24.3% (9/37), 35.1% (13/37), and 16.2% (6/37), respectively. After surgery, the visual function was improved, stabilized, and worsened in 43.2% (16/37), 43.2% (16/37), and 13.5% (5/37) of patients, respectively. Multivariable logistic regression analysis showed that subarachnoid space invasion was the only independent prognostic factor adversely influencing the postoperative visual outcomes. Patients with subarachnoid space invasion had a higher possibility of visual deterioration (36.4% vs. 3.8%; P = 0.021) after transcranial surgery, compared with those without subarachnoid space invasion.

CONCLUSIONS

Visual compromise is still an unignorable complication during transcranial surgery for large-to-giant pituitary adenomas. Subarachnoid space invasion indicated by preoperative magnetic resonance imaging was an independent negative predictor for visual outcomes after surgery.

Aggressive Pituitary Tumor with Crooke's Cells and Invasion of the Posterior Fossa

BACKGROUND

Pituitary adenomas are mostly benign in character and are managed via a transsphenoidal approach in most cases. Crooke's cell adenoma (CCA) is a particular variant accounting for less than 1% of the pituitary adenomas. They have a distinctive histopathologic pattern and behavior.

CASE DESCRIPTION

We present a case of a 56-year-old man with recurrent pituitary adenoma and complicated neurosurgical history. Imaging follow-up showed a suprasellar mass with progressive growth into the posterior fossa. Surgical management via retrosigmoid craniectomy was performed, and histopathology elucidated Crooke's cells.

CONCLUSIONS

CCA is recognized by its local aggressiveness and high recurrence rates. They tend to be locally invasive; however, posterior fossa invasion has not been reported to date. We aim to contribute to the arsenal of differential diagnosis of similar pituitary tumor cases.

Pediatric pituitary adenomas

BACKGROUND

Pediatric pituitary adenomas are a rare medical entity that makes up a small portion of intracranial tumors in children and adolescents. Although benign, the majority of these lesions are secreting functional tumors with the potential for physiological sequela that can profoundly affect a child's development.

FOCUS OF REVIEW

In this review, we discuss the medical and surgical management of these tumors with a focus on clinical presentation, diagnostic identification, surgical approach, and associated adjuvant therapies. We will also discuss our current treatment paradigm using endoscopic, open, and combined approaches to treat these tumors. The management of pituitary tumors requires a multidisciplinary team of surgeons, endocrinologists, and neuroanesthesiologists as well as neurocritical care specialists to deliver comprehensive care.

The optimal surgical techniques for pituitary tumors

In this paper, the currently used and well evaluated techniques for the surgery of pituitary tumors will be reviewed. Since the first surgical approaches to pituitary tumors more than 100 years have elapsed. Various surgical techniques have been developed, refined and standardized. Most of these tumors are to date treated via transsphenoidal approaches. Many pituitary adenomas, particularly, smaller, enclosed ones, can be completely excised and a selective adenomectomy is usually attempted. It leads to remission of hormonal oversecretion and also to recovery of pituitary function in many patients. The resection of pseudocapsule around the adenoma seems to improve the operative results further. Transcranial approaches, employing craniotomies, are still needed in some patients with pituitary adenomas and in many of those harbouring craniopharyngiomas. The operative techniques will be described and briefly commented. Moreover, the application and usefulness of several technical developments will be reviewed, such as the use of the endoscope, magnetic resonance imaging, fluorenscent dyes and neuronavigation. The use of the intraoperative Doppler probe, ultrasound and the value of intraoperative hormonal measurements will be briefly discussed. There is sufficient evidence that the best and optimal outcome in terms of tumor resection and correction of hormonal oversecretion as well as the lowest rate of complications are obtained in centers of excellence with sufficiently experienced, specialized surgeons and a high patient load.

Pediatric Pituitary Adenoma: Case Series, Review of the Literature, and a Skull Base Treatment Paradigm

Background  Pediatric pituitary adenoma is a rare skull base neoplasm, accounting for 3% of all intracranial neoplasms in children and 5% of pituitary adenomas. Compared with pituitary tumors in adults, secreting tumors predominate and longer disease trajectories are expected due to the patient age resulting in a natural history and treatment paradigm that is complex and controversial. Objectives  The aims of this study were to describe a large, single-institution series of pediatric pituitary adenomas with extensive long-term follow-up and to conduct a systematic review examining outcomes after pituitary adenoma surgery in the pediatric population. Methods  The study cohort was compiled by searching institutional pathology and operative reports using diagnosis and site codes for pituitary and sellar pathology, from 1956 to 2016. Systematic review of the English language literature since 1970 was conducted using PubMed, MEDLINE, Embase, and Google Scholar. Results  Thirty-nine surgically managed pediatric pituitary adenomas were identified, including 15 prolactinomas, 14 corticotrophs, 7 somatotrophs, and 4 non-secreting adenomas. All patients underwent transsphenoidal resection (TSR) as the initial surgical treatment. Surgical cure was achieved in 18 (46%); 21 experienced recurrent/persistent disease, with secondary treatments including repeat surgery in 10, radiation in 14, adjuvant pharmacotherapy in 11, and bilateral adrenalectomy in 3. At the last follow-up (median 87 months, range 3-581), nine remained with recurrent/persistent disease (23%). Thirty-seven publications reporting surgical series of pediatric pituitary adenomas were included, containing 1,284 patients. Adrenocorticotropic hormone (ACTH)-secreting tumors were most prevalent (43%), followed by prolactin (PRL)-secreting (37%), growth hormone (GH)-secreting (12%), and nonsecreting (7%). Surgical cure was reported in 65%. Complications included pituitary insufficiency (23%), permanent visual dysfunction (6%), chronic diabetes insipidus (DI) (3%), and postoperative cerebrospinal fluid (CSF) leak (4%). Mean follow-up was 63 months (range 0-240), with recurrent/persistent disease reported in 18% at the time of last follow-up. Conclusion  Pediatric pituitary adenomas are diverse and challenging tumors with complexities far beyond those encountered in the management of routine adult pituitary disease, including nuanced decision-making, a technically demanding operative environment, high propensity for recurrence, and the potentially serious consequences of hypopituitarism with respect to fertility and growth potential in a pediatric population. Optimal treatment requires a high degree of individualization, and patients are most likely to benefit from consolidated, multidisciplinary care in highly experienced centers.

Microscopic surgery for pituitary adenomas to preserve the pituitary gland and stalk

Surgery is the primary treatment of choice for all symptomatic pituitary adenomas except prolactinomas. Common postoperative complications include endocrinopathies, vision impairment and cerebrospinal fluid leak. The present study assessed 153 continuous microscopic surgeries for pituitary adenomas performed by an author of the present study between 2010 to 2014. Patients underwent either transphenoidal or transcranial surgery depending on their individual tumor characteristics. Five typical cases are presented in the present study and intraoperative identification and preservation of the gland and stalk were discussed. Postoperative complications were analyzed and compared with the literature. In the present analysis, 90.2% patients received transphenoidal surgery, and the rest underwent transcranial operation. Gross total resection was achieved in 81.2% patients in the transphenoidal group and 46.7% patients in the transcranial group. No new hypopituitarism or worsening of the pre-existing pituitary dysfunctions was detected. The most common postoperative endocrinopathy was diabetes insipidus (transphenoidal group, 4.3%; transcranial group, 26.7%). All patients were fully recovered prior to discharge. The findings indicated the importance of pituitary gland and stalk preservation during the microscopic surgery to minimize postoperative morbidity and mortality, without compromising the extent of tumor resection. Based on preoperative imaging characteristics and intraoperative observations, surgeons should try all possible means to preserve the pituitary stalk and gland during surgery in order to minimize postoperative endocrinopathies and improve quality of life.

Clinical Predictors of Diabetes Insipidus After Transcranial Surgery for Pituitary Adenoma

OBJECTIVE

Diabetes insipidus (DI) is a well-known complication of transsphenoidal pituitary adenoma surgery. However, the risk factors for DI after transcranial surgery have not been clarified. In this study, the clinical parameters for predicting DI after transcranial surgery were investigated.

METHODS

The perioperative records of 90 patients who underwent transcranial (TC) surgery at the authors' institution between November 2011 and March 2013 were chosen from 1657 patients with pituitary adenoma and retrospectively analyzed. The degree of deformation of the third ventricle and hypothalamus were assessed by preoperative magnetic resonance imaging.

RESULTS

Immediate postoperative DI was found in 30 patients (33.3%). Persistent DI was noted in 11 patients (12.6%). Compared with patients in the nonpostoperative DI group, those with postoperative DI had a higher degree of deformation of the third ventricle and hypothalamus (P < 0.001). In a binary logistic regression analysis, the degree of deformation of the third ventricle and hypothalamus (odds ratio [OR], 3.079; 95% confidence interval [CI], 1.600-5.925; P = 0.001) had a significant positive correlation with immediate postoperative DI, as well as postoperative hemorrhage (OR, 6.235, 95% CI, 1.457-26.689; P = 0.014). Postoperative hemorrhage (OR, 4.363; 95% CI, 1.021-18.647; P = 0.047) showed a positive correlation with permanent DI, as well as the degree of deformation of the third ventricle and hypothalamus (OR, 2.336; 95% CI, 1.005-5.427; P = 0.049).

CONCLUSIONS

The degree of deformation of the third ventricle and hypothalamus assessed by preoperative magnetic resonance imaging may help to predict postoperative DI. Postoperative hemorrhage might increase the incidence of postoperative DI, whether it is immediate postoperative DI or permanent DI.

A review on the diagnosis and treatment of patients with clinically nonfunctioning pituitary adenoma by the Neuroendocrinology Department of the Brazilian Society of Endocrinology and Metabolism

Clinically nonfunctioning pituitary adenomas (NFPA) are the most common pituitary tumors after prolactinomas. The absence of clinical symptoms of hormonal hypersecretion can contribute to the late diagnosis of the disease. Thus, the majority of patients seek medical attention for signs and symptoms resulting from mass effect, such as neuro-ophthalmologic symptoms and hypopituitarism. Other presentations include pituitary apoplexy or an incidental finding on imaging studies. Mass effect and hypopituitarism impose high morbidity and mortality. However, early diagnosis and effective treatment minimizes morbidity and mortality. In this publication, the goal of the Neuroendocrinology Department of the Brazilian Society of Endocrinology and Metabolism is to provide a review of the diagnosis and treatment of patients with NFPA, emphasizing that the treatment should be performed in reference centers. This review is based on data published in the literature and the authors' experience. Arch Endocrinol Metab. 2016;60(4):374-90.

Combined surgical and medical treatment of giant prolactinoma: case report

The operative management of giant pituitary prolactinoma represents a significant challenge for neurosurgeons, due to the degree of local tumor infiltration into adjacent structures such as cavernous sinus. The degree of parasellar tumor extension can be classified according to the Knosp grading system’ while suprasellar extension is qualified in accordance with the modified Hardys classification system. This report describes the case of a male patient with a giant pituitary prolactinoma in which a partial tumor resection via a subfrontal approach was achieved. Typically, resection rates of less than 50% have been reported following surgery on giant pituitary adenomas. Prolactin levels were very high, consistent with invasive giant prolactinoma. Our patient was treated with Cabergoline which eventually normalized the prolactin level and significantly reduced the size of the residual tumor. This case serves to illustrate that in the presence of significant suprasellar and parasellar extension, multi-modal treatment strategies with surgery and dopamine agonist, is the gold standard in the management of locally aggressive pituitary prolactinomas.

Vascular Complications of Intercavernous Sinuses during Transsphenoidal Surgery: An Anatomical Analysis Based on Autopsy and Magnetic Resonance Venography

Purpose

Vascular complications induced by intercavernous sinus injury during dural opening in the transsphenoidal surgery may contribute to incomplete tumour resections. Preoperative neuro-imaging is of crucial importance in planning surgical approach. The aim of this study is to correlate the microanatomy of intercavernous sinuses with its contrast-enhanced magnetic resonance venography (CE-MRV).

Methods

Eighteen human adult cadavers and 24 patients were examined based on autopsy and CE-MRV. Through dissection of the cadavers and CE-MRV, the location, shape, number, diameter and type of intercavernous sinuses were measured and compared.

Results

Different intercavernous sinuses were identified by their location and shape in all the cadavers and CE-MRV. Compared to the cadavers, CE-MRV revealed 37% of the anterior intercavernous sinus, 48% of the inferior intercavernous sinus, 30% of the posterior intercavernous sinus, 30% of the dorsum sellae sinus and 100% of the basilar sinus. The smaller intercavernous sinuses were not seen in the neuro-images. According to the presence of the anterior and inferior intercavernous sinus, four types of the intercavernous sinuses were identified in cadavers and CE-MRV, and the corresponding operative space in the transsphenoidal surgical approach was implemented.

Conclusion

The morphology and classification of the cavernous sinus can be identified by CE-MRV, especially for the larger vessels, which cause bleeding more easily. Therefore, CE-MRV provides a reliable measure for individualized preoperative planning during transsphenoidal surgery.

A Purely Endoscopic and Simultaneous Transsphenoidal and Transcranial Keyhole Approach for Giant Pituitary Adenoma Resection: A Technical Case Report

A combined transsphenoidal-transcranial approach for the resection of pituitary adenomas has previously been reported. While this approach is useful for specific types of pituitary adenomas, it is an invasive technique. To reduce the invasiveness of this approach, we adopted the keyhole concept for pituitary adenoma resection. A 23-year-old man presented at a local hospital with a 6-month history of bilateral hemianopia. Magnetic resonance imaging revealed a large pituitary adenoma extending from the sella turcica toward the right frontal lobe. Endoscopic transsphenoidal surgery was planned at a local hospital; however, the operation was abandoned at the start of the resection because of the firm and fibrous nature of the tumor. The patient was subsequently referred to our hospital for additional surgery. The tumor was removed purely endoscopically via a transsphenoidal and transcranial route. Keyhole craniotomy, 3 cm in diameter, was performed, and a tubular retractor was used to achieve a wider surgical corridor; this enabled better visualization and dissection from the surrounding brain and provided enough room for the use of surgical instruments under endoscopic view. The tumor was successfully removed without complication. This is the first case report to describe the resection of a giant pituitary adenoma using a purely endoscopic and simultaneous transsphenoidal and transcranial keyhole approach.

The current role of transcranial surgery in the management of pituitary adenomas

The aim of this study was to determine the factors influencing the use of a transcranial (TC) approach in pituitary adenomas and suggest a decision-making tree for the surgical strategy. The data for 23 (4.6%) patients who underwent TC surgery from amongst 494 pituitary adenomas were retrospectively analyzed. Eight factors on magnetic resonance imaging (MRI) that could predict a difficult transsphenoidal (TS) surgery were noted. Adverse findings at TS surgery leading to a 2nd stage TC surgery were documented. Eighteen of the 23 cases were giant adenomas. Thirteen patients underwent TC surgery alone or as an initial approach when combined with TS while 10 underwent 2nd stage TC surgery following a TS approach. Most cases in the first group had 3 or more radiological factors in combination with a small sella. The 2nd group had higher sellar tumor volumes and fewer unfavourable radiological factors that led to the initial use of the TS approach. A hard, fibrous consistency or a significant residue obscured from the surgeon's view, and difficulty in hemostasis were additional factors prompting the use of a TC approach. Tumor excision ≥90% could be achieved in 13 cases (56.5%). Post-operative RT was administered in 12 patients. There were 2 deaths (8.7%) and the major morbidity rate was 43 %. Despite advances in endoscopic surgery the TC approach may be required in 5% of cases. A study of the preoperative MRI for factors that predict difficulty with the TS approach might encourage the surgeon to consider a TC surgery either as an initial approach or combined with a TS surgery.

Pituitary disease mortality: is it fiction?

During the last 20 years a tremendous improvement in the care of patients with pituitary tumors and of hypopituitarism has been achieved. If we resolve most of the possible causes of the increased cardiovascular disease and stroke mortality a normal survival is expected in these patients. Recently, a large population based study showed a decline in the risk of non-fatal stroke and of non-fatal cardiac events in GH deficient patients. This improvement was achieved by complete hormone replacement, including long term GH replacement, together with prescription of cardio protective drugs. If we follow the latest achievements in pituitary imaging, surgery techniques, hormone substitutions, cardio protective medications, we would expect a normal longevity in these patients. This review will focus on; (1) pituitary insufficiencies and hormone substitutions, (2) modes of cranial radiotherapy, and (3) new techniques in the surgery of a pituitary adenoma.

Endoscopic endonasal surgery for giant pituitary adenomas: advantages and limitations

OBJECT

Giant pituitary adenomas (> 4 cm in maximum diameter) represent a significant surgical challenge. Endoscopic endonasal surgery (EES) has recently been introduced as a treatment option for these tumors. The authors present the results of EES for giant adenomas and analyze the advantages and limitations of this technique.

METHODS

The authors retrospectively reviewed the medical files and imaging studies of 54 patients with giant pituitary adenomas who underwent EES and studied the factors affecting surgical outcome.

RESULTS

Preoperative visual impairment was present in 45 patients (83%) and partial or complete pituitary deficiency in 28 cases (52%), and 7 patients (13%) presented with apoplexy. Near-total resection (> 90%) was achieved in 36 patients (66.7%). Vision was improved or normalized in 36 cases (80%) and worsened in 2 cases due to apoplexy of residual tumor. Significant factors that limited the degree of resection were a multilobular configuration of the adenoma (p = 0.002) and extension to the middle fossa (p = 0.045). Cavernous sinus invasion, tumor size, and intraventricular or posterior fossa extension did not influence the surgical outcome. Complications included apoplexy of residual adenoma (3.7%), permanent diabetes insipidus (9.6%), new pituitary insufficiency (16.7%), and CSF leak (16.7%, which was reduced to 7.4% in recent years). Fourteen patients underwent radiation therapy after EES for residual mass or, in a later stage, for recurrence, and 10 with functional pituitary adenomas received medical treatment. During a mean follow-up of 37.9 months (range 1-114 months), 7 patients were reoperated on for tumor recurrence. Three patients were lost to follow-up.

CONCLUSIONS

Endoscopic endonasal surgery provides effective initial management of giant pituitary adenomas with favorable results compared with traditional microscopic transsphenoidal and transcranial approaches.

Extended endoscopic transplanum-transtuberculum approach for pituitary adenomas

Few pituitary adenomas require removal through a transcranial route. This may be associated with more significant morbidity and mortality, compared to the transsphenoidal approach. An endoscopic, extended, transplanum-transtuberculum approach (ETTA) in selected pituitary adenomas may offer an alternative to the transcranial route. We describe our technique and experience of ETTA in pituitary adenomas over 10 years. Between 2000 and 2010, we performed 700 endoscopic endonasal procedures for pituitary adenomas. Nineteen patients (13 men; mean age, 48 years; range, 22-76 years) underwent 22 ETTAs. Thirteen patients had non-functioning adenomas. Three tumor groups were identified: (1) tumors developing in or around the pituitary stalk; (2) tumours with sub- frontal extension and (3) tumours with a major extrasellar component. Mean follow-up was 37 months (range 6-72 months). Gross total resection was achieved in 11 procedures (no recurrences), with partial tumour resection in 11 procedures. Of the 12 patients with visual symptoms, ten improved. Of eight patients with hormonal hypersecretion four were cured. Complications included CSF leak (14%), haemorrhage (9%), hemiplegia (5%). There were no mortalities. Experience using the ETTA for pituitary adenomas is limited because it is indicated in highly selected cases (3.1% of our series). An absolute indication is represented by ectopic secreting pituitary stalk/peri-stalk adenomas. ETTA is a useful option in midline frontal adenomas and adenomas with a major extrasellar component, but has a higher morbidity than that seen in the standard transsphenoidal approach. A study comparing ETTA versus transcranial resection is highly desirable.

Meningiomas, nerve sheath tumors, and pituitary tumors: diagnosis and treatment

This article gives an overview of meningiomas, pituitary tumors, and intracranial nerve sheath tumors as regards epidemiology, diagnosis, and treatment. Discussion includes the definition of these tumors and their symptomatology, diagnostic procedures, treatment options, surgical techniques, and outcomes.

Surgery and radiosurgery for acromegaly: a review of indications, operative techniques, outcomes, and complications

Among multimodality treatments for acromegaly, the goals of surgical intervention are to balance maximal tumor resection while preserving normal pituitary function and maintaining patient safety. The resection of growth hormone-(GH-) secreting pituitary adenomas in the hands of experienced surgeons results in hormonal remission in 50-70% of patients. Acromegalic patients often have medical comorbidities and anatomical variations complicating anesthesia and surgical management. Despite these challenges, complications such as CSF leak or new hypopituitarism following surgery remain uncommon. Over the past decade, endoscopic approaches to pituitary tumors have improved visualization and facilitated identification of additional tumor using angled telescopes. Patients with persistent acromegaly following surgery require continued medical and/or radiation-based interventions. The adjunctive use of stereotactic radiosurgery offers hormonal remission in 40-50% of patients. In this article, the current preoperative evaluation, indications for surgery, surgical approaches, role of radiosurgery, complications, and remission criteria following operative resection of GH adenomas are reviewed.

The role of outcomes data for assessing the expertise of a pituitary surgeon

PURPOSE OF REVIEW

Over the past four decades, advances in surgical technique, instrumentation, and anatomical knowledge have fueled the evolution and sophistication of transsphenoidal pituitary surgery. Paralleling these advances have been major improvements in endocrinological and overall clinical outcomes in patients with pituitary adenomas and other parasellar lesions such as Rathke's cleft cysts and craniopharyngiomas. In this review, we assess the impact of neurosurgeon expertise as a determinant of outcome in pituitary surgery.

RECENT FINDINGS

Published data since the 1980s indicate that remission rates, overall clinical outcomes and surgical complication rates in pituitary and parasellar surgery are related to neurosurgeon practice volume and cumulative clinical experience. More recently, pituitary surgery has been increasingly performed using an endonasal endoscopic approach. Reports over the last decade suggest when an experienced pituitary neurosurgeon performs a fully endoscopic or endoscope-assisted tumor removal; outcomes are similar if not better than when performed by a traditional microscopic transsphenoidal approach.

SUMMARY

A focused clinical practice and large transsphenoidal surgical volume appear to be important outcome determinants for patients with pituitary and parasellar tumors. Strategies that may further improve patient outcomes include establishing guidelines for pituitary tumor centers of excellence and more focused residency and fellowship training in endonasal endoscopic transsphenoidal surgery. Encouraging regionalization of care to higher volume pituitary tumor centers of excellence and promoting patient education on the importance of surgical expertise may further enhance pituitary patient outcomes.

Endonasal transsphenoidal surgery and multimodality treatment for giant pituitary adenomas

OBJECTIVE

Giant pituitary adenomas (> or =40 mm) pose a major management challenge. We describe the experience of a single surgeon and a dedicated neuro-endocrine team with multimodality treatment of these tumours in three specialized institutions.

DESIGN

Retrospective data set analyses.

PATIENTS

Fifty-one consecutive patients with a giant adenoma (39 endocrine-inactive, 12 endocrine-active; mean tumour diameter 45 mm) treated over 10 years by an endonasal transsphenoidal approach were included. All patients had surgical resection followed by radiotherapy and/or medical therapy as judged necessary.

MEASUREMENTS

Hormonal and visual status, extent of resection, tumour control rates, complications and use of medical and radiotherapy were evaluated.

RESULTS

Surgery resulted in gross total, near total and subtotal removal in21 (41%), 10 (20%) and 20 (39%) patients respectively. Complete tumour removal was associated with absence of cavernous sinus invasion (P < 0.001). Long-term endocrine function improved in 49% of patients and new endocrinopathy occurred in 14.6%; 76% required long-term hormone replacement therapy. Vision improved in 81.5% of the patients and there was no visual worsening. At the last follow up (median 30 months), tumour control was achieved in 96% of patients: 59% with surgery alone, 20% with surgery plus focussed radiotherapy, 18% with surgery and medical therapy and two with all three modalities.

CONCLUSIONS

Endonasal surgery provides effective initial treatment for patients with giant adenomas. Multimodality therapy was needed in almost 50% of patients and this rate will likely increase with longer follow up. Close collaboration of neurosurgeons with endocrinologists and radiation oncologists is essential for optimal treatment of patients with these challenging tumours.

Surgical treatment of pituitary tumours

The surgical treatment of pituitary tumours underwent considerable evolution during the past centennial. Since Schloffer's first description, excellent surgeons refined the surgical techniques, utilised hormonal measurements and imaging investigations at different times to define surgical success or failure. To date, transsphenoidal surgery is the approach of choice for over 90% of pituitary tumours, but still transcranial operations are needed even in experienced hands when asymmetrical and large pituitary tumours with minor intrasellar components present. When the indication for surgery stands, the complication rate to date is relatively low, particularly if the surgeon and his or her centre have sufficient experience in the field. In microadenomas, the success rate reported from expert authors approaches 90%. Generally speaking, patients with non-functioning pituitary adenomas, acromegaly, thyrotropinomas and Cushing's disease are excellent candidates for primary surgical treatment. Re-operations are generally associated with less favourable outcomes. In prolactinomas, the primary therapy is medical; however, when dopamine agonists are not well tolerated or inefficient, an operative treatment should be considered. Although alternative medical treatments exist in acromegaly and thyrotropinomas, surgical treatment is relatively cheap. The implementation of endoscope-assisted, entirely endoscopic, image-guided surgery and intra-operative magnetic resonance (MR) imaging, particularly in combination with utilisation of the established microsurgical techniques, extends the surgical spectrum. Lesions become surgically accessible, which one did not dare to touch even a century ago. Moreover, it seems that the patient's safety has increased and more patients have their tumours completely resected, which is equivalent to a higher remission rate in hormonally active tumours.