Recurrent Cushing's Disease in Adults: Predictors and Long-Term Follow-Up.

Cushing's disease (CD) is characterized by endogenous hypercortisolism that is associated with increased mortality and morbidity. Due to high recurrence rates in CD, the determination of high-risk patients is of paramount importance. In this study, we aimed to determine recurrence rates and clinical, laboratory, and histological predictors of recurrence in a high volume single-center. This retrospective study included 273 CD patients operated in a single pituitary center between 1997 and 2020. The patients with early postoperative remission were further grouped according to recurrence status (recurrent and sustained remission groups). Demographic, radiologic, laboratory, pathologic, and follow-up clinical data of the patients were analyzed and compared between groups. The recurrence rate was 9.6% in the first 5 years; however, the overall recurrence rate was 14.2% in this study. Higher preoperative basal ACTH levels were significantly correlated with CD recurrence even with ACTH levels adjusted for tumor size, Ki-67 levels, and tumoral invasion. Recurrence rates were significantly higher in patients with ACTH levels higher than 55 pg/ml, tumor diameter>9.5 mm, and if adrenal axis recovery was before 6 months. The severity of hypercortisolism, morbidities, and demographic factors except age were not predictive factors of recurrence. Based on our study data, younger age at diagnosis, a diagnosis of osteoporosis, higher preoperative ACTH levels, larger tumor size, invasive behavior, higher Ki 67 index, and early recovery of the adrenal axis during the postoperative period attracted attention as potential predictors of recurrent disease.

Endoscopic transnasal surgery in optic pathway gliomas located in the chiasma-hypothalamic region: case series of ten patients in a single-center experience and endoscopic literature review.

OBJECTIVE: Optic pathway gliomas (OPGs) constitute approximately 3-5% of childhood intracranial tumors. In this study, the authors presented their experience of using the endoscopic endonasal approach to treat patients with OPG located in the chiasma-hypothalamic region and aimed to use the infrachiasmatic corridor in the endoscopic endonasal approach as an alternative to the transcranial approach in the surgical necessity of OPGs. METHODS: We retrospectively analyzed the data of ten patients diagnosed with OPG histopathologically among 3757 cases who underwent endoscopic endonasal surgery between August 1997 and March 2021 at Kocaeli University Faculty of Medicine Pituitary Research Center and Department of Neurosurgery. Mean follow-up period 48.5 months. During the postoperative follow-up period, 3 of these 10 patients underwent reoperation due to tumor recurrence. Combined (endoscopic endonasal approach + transcranial approach) approach was applied to 2 patients in the same session. Surgical and clinical outcomes were evaluated in detail. RESULTS: Ten patients with a mean patient age of 20.6 ± 11.4 were included in this study. The most common complaint was visual impairment. After surgery, improvement in visual impairment was observed in five patients. No increase in postoperative visual impairment was observed in any of the patients. Postoperative panhypopituitarism was not observed in any of the patients. STR resection was performed in 5 patients and NTR resection in 5 patients. No additional treatment was required during follow-up in 4 of 5 patients who underwent NTR. A total of 6 patients received postoperative radiotherapy treatment. CONCLUSIONS: In gliomas located in the chiasma-hypothalamic region, appropriate patient selection and endoscopic endonasal surgical treatment may contribute to the elimination of symptoms due to the mass effect of the tumor. It may also contribute to keeping the disease under control with targeted adjuvant therapies by clarifying the pathological diagnosis of the lesion.

The association of bone mineral density Z-score with the early postoperative remission and characteristics of bone mineral loss in patients with Cushing's disease: a retrospective study.

AIM: To investigate the association of bone mineral density (BMD) Z-scores with early-postoperative remission rate and clinical parameters in patients with Cushing's disease (CD). METHODS: We retrospectively evaluated the records of patients diagnosed with CD. After the exclusion of 230 patients, 87 CD patients were finally enrolled. BMD was determined by dual-energy x-ray absorptiometry (DXA) at the lumbar spine 1-4 (L1-4) and left femur. Early-postoperative remission was defined as a morning cortisol concentration on the first day after surgery of less than 5 µg/dL. The diagnosis of BMD "below the expected range for age" was defined as a Z-score≤-2.00 standard deviations. RESULTS: DXA results were not significantly associated with early postoperative remission. They also did not significantly differ between eugonadal and menopausal groups. Preoperative morning cortisol significantly negatively but weakly correlated with Z-score of the total femur, while preoperative adrenocorticotropic hormone/cortisol ratio positively but weakly correlated with DXA results of L1-4. CONCLUSION: The severity of bone loss was not significantly related to the failure of transsphenoidal surgery for Cushing's disease.

An endoscopic endonasal approach to craniopharyngioma via the infrachiasmatic corridor: a single center experience of 84 patients.

OBJECT: The infrachiasmatic corridor is the most important surgical access route for craniopharyngiomas and was identified and used in clinical series. The aims of this study were to describe the characteristics that assist dissection and resection rates in endoscopic surgery of solid, cystic, and recurrent cases and their importance in the infrachiasmatic corridor in endoscopic surgery. METHODS: One hundred operations on 84 patients with pathologically identified craniopharyngioma were included in the study. The MRI findings were evaluated, and the location of the lesions was classified as (1) infrasellar; (2) sellar; or (3) suprasellar. In the sagittal plane, we measured the longest diameter of cystic and solid components and the height of chiasm-sella. Images were assessed for the extent of resection and were classified as gross total resection. This was deemed as the absence of residual tumor and subtotal resection, which had residual tumor. RESULTS: The infrasellar location was reported in 7/84 (8.3%) patients, the sellar location in 8/84 (9.5%), and the suprasellar location in 69/84 (82.1%) patients. The narrow and high chiasm-sella were observed in 28/69 (40.5%) and 41/69 patients (59.4%), respectively. The mean distance of the chiasm-sella was 9.46± 3.76. Gross total tumor resection was achieved in 60/84 (71.4%) and subtotal tumor resection was performed in 24/84 (28.6%) patients. The results revealed that suprasellar location (OR: 0.068; p = 0.017) and recurrent cases (OR: 0.011; p<0.001) were negative predictive factors on GTR. Increasing the experience (OR: 42,504; p = 0.001) was a positive predictor factor for GTR. CONCLUSION: An EETS approach that uses the infrachiasmatic corridor is required for skull base lesions extending into the suprasellar area. The infrachiasmatic corridor can determine the limitations of endoscopic craniopharyngioma surgery. This corridor is a surgical safety zone for inferior approaches.

Extended endoscopic transsphenoidal approach infrachiasmatic corridor.

An extended endoscopic transsphenoidal approach is required for skull base lesions extending to the suprasellar area. Inferior approach using the infrachiasmatic corridor allows access to the lesions through the tumor growth that is favorable for the extended transsphenoidal approaches. Infrachiasmatic corridor is a safer route for the inferior approaches that is made up by basal arachnoid membrane and Liliequist's membrane with its leaves (diencephalic and mesencephalic leaf). This area extends from the optic canal and tuberculum sella to the corpus mamillare. We performed extended endoscopic approach using the infrachiasmatic corridor in 52 cases, including tuberculum sella meningiomas (n:23), craniopharyngiomas (n:16), suprasellar Rathke's cleft cyst (n:6), pituitary adenoma (n:2), fibrous dysplasia (n:1), infundibular granulosa cell tumor (n:2), and epidermoid tumor (n:2). Total resection was achieved in 17 of 23 (74%) with tuberculum sellae meningioma using infrachiasmatic approach. Twenty patients presented with visual disorders and 14 of them improved. There were two postoperative cerebrospinal fluid (CSF) leakages and one transient diabetes insipidus and one permanent diabetes insipidus. Sixteen patients were operated on by the infrachiasmatic approach for craniopharyngiomas. Improvement was reached in seven of eight patients presented with visual disorders. Complete tumor resection was performed in 10 of 16 cases and cyst aspiration in 4 cases, and there were remnants in two cases. Postoperative CSF leakage was seen in two patients. Infrachiasmatic corridor provides an easier and safer inferior route for the removal of middle midline skull base lesions in selected cases.

Rarely Used Endoscopic Transnasal Transdiaphragmatic Technique in Patients with Suprasellar Extension: A Tertiary Center's Experience with Eleven Patient Cases.

OBJECTIVE: As surgical techniques become less invasive, the use of endoscopy in brain surgery supports this trend. Numerous endoscopic surgical approaches have been defined, especially for skull base diseases. The current study summarizes our experience of using the rarely reported endoscopic transnasal transdiaphragmatic approach through the existing hole in the diaphragma sella to access lesions extending into the suprasellar region. METHODS: Our surgical team performed 4876 endoscopic endonasal surgeries between August 1997 and December 2022 at the Department of Neurosurgery, Pituitary Research Center, Faculty of Medicine, Kocaeli University. The study retrospectively analyzed data from 11 patients who had undergone endoscopic transnasal transdiaphragmatic surgery since January 2020. Preoperative and postoperative magnetic resonance imaging, pituitary function examination, and clinical observation were carried out. RESULTS: The mean age of the patients was 31.1 ± 10.7 years and the female/male ratio was 6:5. Pathologic subtypes observed included breast cancer metastasis (n = 1), adrenocorticotropic hormone-secreting adenoma (n = 4), growth hormone-secreting adenoma (n = 3), craniopharyngioma (n = 2), and Rathke cleft cyst (n = 1). The mean postoperative hospital stay was 4.7 ± 1.1 days and none of the patients showed cerebrospinal fluid leakage during this period. CONCLUSIONS: The endoscopic transnasal transdiaphragmatic approach may be considered an alternative to the conventional extended endoscopic transnasal approach in patients with lesions extending into the suprasellar region. The main strength of this method is that it facilitates suprasellar region access through a small dural incision and bone defect in the base of the skull. As a result, it also reduces the risk of postoperative cerebrospinal fluid leakage and associated complications.

A Novel Fusion of Radiomics and Semantic Features: MRI-Based Machine Learning in Distinguishing Pituitary Cystic Adenomas from Rathke's Cleft Cysts.

Objectives: To evaluate the performances of machine learning using semantic and radiomic features from magnetic resonance imaging data to distinguish cystic pituitary adenomas (CPA) from Rathke's cleft cysts (RCCs). Materials and Methods: The study involved 65 patients diagnosed with either CPA or RCCs. Multiple observers independently assessed the semantic features of the tumors on the magnetic resonance images. Radiomics features were extracted from T2-weighted, T1-weighted, and T1-contrast-enhanced images. Machine learning models, including Support Vector Machines (SVM), Logistic Regression (LR), and Light Gradient Boosting (LGB), were then trained and validated using semantic features only and a combination of semantic and radiomic features. Statistical analyses were carried out to compare the performance of these various models. Results: Machine learning models that combined semantic and radiomic features achieved higher levels of accuracy than models with semantic features only. Models with combined semantic and T2-weighted radiomics features achieved the highest test accuracies (93.8%, 92.3%, and 90.8% for LR, SVM, and LGB, respectively). The SVM model combined semantic features with T2-weighted radiomics features had statistically significantly better performance than semantic features only (p = 0.019). Conclusion: Our study demonstrates the significant potential of machine learning for differentiating CPA from RCCs.

Surgical outcomes and follow-up results of 53 pediatric craniopharyngioma cases: a single-center study.

OBJECTIVE: Craniopharyngiomas are locally invasive neoplasms, and they cause potential lifelong morbidity because of their tendency for local recurrence. Despite advancements in endoscopic techniques, gross-total resection (GTR) of tumors with invasion or adhesion to important surrounding anatomical structures is extremely difficult. The authors present a single-center study that evaluated the impact of the endoscopic endonasal approach (EEA) on the surgical outcomes of pediatric craniopharyngiomas, the factors affecting the resection rate, and recurrence. METHODS: A total of 44 pediatric patients (age ≤ 18 years) who were treated via the EEA for craniopharyngioma from August 1997 to June 2022, as well as their 53 operations, were included in this study. The preoperative radiological configuration and surgical data of these cases were assessed. Also, preoperative and postoperative clinical (endocrinologic, neurological, and ophthalmological), hypothalamic, physical and social development, and neurocognitive assessment data were described. RESULTS: In total, 37 cases (69.8%) had no history of operation beforehand. The most common symptoms at presentation were endocrine disturbances (98.1%), headache without vomiting (84.3%), and visual disturbance (51%). Cases were classified as infrasellar (1.9%), sellar (32.1%), sellar-suprasellar (52.8%), and suprasellar (13.2%) localization. GTR was achieved in 34/53 cases (64.1%). The rate of GTR was higher in infrasellar and sellar tumors compared with sellar-suprasellar and suprasellar tumors (p = 0.003), and preoperative hypothalamic involvement was associated with lower likelihood of GTR (p = 0.024). Moreover, with experience, the rate of GTR increased (p = 0.037). Postoperative complications, other than endocrine impairment, occurred in 10/53 cases (18.9%). The mean duration of follow-up was 53.57 months. At follow-up, 21/53 (39.6%) cases presented with tumor recurrence. The 5-year progression-free survival (PFS) rate was 48.5%. There was a statistically significant difference between the GTR and other-than-GTR groups in terms of PFS (p < 0.001). According to univariate analysis, smaller tumor (p = 0.017), infrasellar and sellar localization (p = 0.031), and GTR (p < 0.001) were significantly associated with decreased rate of recurrence. Also, there was a statistically significant association between the recurrence rate and adhesion strength of the tumor (p < 0.001). CONCLUSIONS: This retrospective cohort study revealed surgical indications for EEA, as well as factors affecting the resection rate, recurrence, and quality of life during the follow-up period of the included cases. The authors believe that GTR should be the goal for craniopharyngioma treatment, but the authors' treatment approach was to provide a balance between radical surgery with maximum safety and adjuvant treatment for long-term disease control.

Operative Nuances of Capsular Dissection Techniques and Capsule Morphology in Pituitary Adenomas: Past 1-Year Case Experiences of a Tertiary Center.

BACKGROUND AND OBJECTIVES: The widespread use of endoscope and increased surgical experiences in pituitary adenomas (PAs) has raised the expectations for higher resection and cure rates. The subject that will meet this expectation in all types of adenomas is the capsule and its dissection. The purpose of this study was to go beyond the commonly mentioned pseudocapsule definition for small-sized adenomas in previous studies and to describe the capsule structure in different morphologies present in pituitary adenomas of all sizes. This includes detailing the nuances of capsular dissection (CD) and presenting postoperative surgical outcomes through the experiences of a high-volume tertiary center. METHODS: In our center, 534 patients underwent endoscopic trans-sphenoidal surgery because of pituitary adenoma in 2022 by the same surgeon. The data of the patients were examined retrospectively. The surgical techniques applied were grouped as adenoma resection only, capsular resection after internal debulking, and direct extracapsular resection. RESULTS: CD was performed in 275 (51.5%) patients. The gross total resection (GTR) rate in nonsecretory adenomas with and without CD was 90.7% (97/107) and 90.7% (97/107), respectively. The remission rate in secretory adenomas with and without CD was 81.0% (136/168) and 44.0% (67/152), respectively. When the patients were examined in 2 groups as those who underwent CD and those who did not, the application of CD had a positive predictive value in terms of GTR/remission (P: .036). Capsule thickness was not found to be statistically significant depending on tumor subtype, size, and aggressiveness, but capsule thickness was statistically significant in terms of total capsular resection (P: .045). CONCLUSION: The morphology of the capsule, tumor size/subtype/consistency, and patient-specific factors are crucial for the selection of the surgical technique to be applied. It is possible to increase the GTR/remission rates in adenomas of all sizes by capsule dissection. Moreover, performing CD does not contribute significantly to the development of potential complications in such cases.

Endoscopic distinction between capsule and pseudocapsule of pituitary adenomas.

BACKGROUND: Pseudocapsules were first identified in pituitary adenoma surgery in 1936. Since then, the distinction between pituitary capsules and pseudocapsules has been unclear, and the definitions of these entities have varied. In this study, pituitary capsules and extracapsular dissection were examined retrospectively, intra- and extrapseudocapsular resection was evaluated, and dissection of the pituitary adenoma and pseudocapsule was examined prospectively. METHODS: Between January 2009 and May 2012, endoscopic transsphenoidal pituitary surgery was performed on 224 patients in the Department of Neurosurgery, Kocaeli University Faculty of Medicine, Turkey. Data for 174 patients were analyzed retrospectively between January 2009 and December 2011, and 50 patients treated between December 2011 and May 2012 were included in a prospective study. RESULTS: In the retrospective phase of the study, capsules were examined in 21 of the 174 patients on whom extracapsular resection had been performed. In the 50 cases treated between December 2011 and May 2012, dissection of the pituitary capsule, adenohypophysis, and pseudocapsule was performed. In 30 patients in the prospective phase of the study, pseudocapsules were identified during intraoperative endoscopic observation. Remission was achieved in 28 of 33 functioning adenomas in the prospective study. The mean follow-up period in this group was 13 months. CONCLUSION: The endoscopic and histopathological evidence provided in this study demonstrates that the pituitary capsule and pseudocapsule are distinct structures. In addition, it is also shown that extracapsular dissection can be performed in functioning adenomas that invade the suprasellar region. Significantly higher rates of total resection and higher remission rates were observed in cases where extra- and intrapseudocapsular dissection was required.

Endoscopic Endonasal Approach Limitations and Evolutions for Tuberculum Sellae Meningiomas: Data from Single-Center Experience of Sixty Patients.

AIM: To determine the limits, to show the effect of tumor consistency on resection rates and to present the sinonasal morbidity rate in patients with tuberculum sellae meningiomas who underwent endoscopic endonasal approach. MATERIAL AND METHODS: We reviewed the medical data, radiological images, and surgical videos of the patients with pathologically confirmed meningiomas originating from the tuberculum sellae and they were operated via endoscopic endonasal approach between August 1997 and December 2020. We used our endoscopic classification based on infrachiasmatic corridor. In this classification, tumors were divided into those within the infrachiasmatic corridor and proximity of the optic nerve, internal carotid artery, and anterior artery complex and those outside the infrachiasmatic corridor. RESULTS: Gross total resection was achieved in 45/60 (75%) patients. We found that tumor consistency was statistically significant on resection rates. Simultaneously, tumor median diameters on the anteroposterior (≤21.15 mm), transverse (≤19.75 mm), and superoinferior (≤15 mm) axes were statistically significant on resection rates. CONCLUSION: In summary, the most important factor in selecting the surgical technique is the tumor size. Infrachiasmatic corridor boundaries are the limitations of endoscopic approach. These limitations can change based on surgeon's experience. Also, tumor consistency is a factor that affecting degree of tumor resection rates.

Endoscopic Transnasal Approach for Microprolactinomas with Experience of 105 Cases in a Single Center: Paradigmal Shift for Conventional Medical Therapy.

OBJECTIVE: The classically recommended first-line therapy for microprolactinomas is medical therapy. In the presence of drug resistance and intolerance after the use of dopamine agonists or when the patients prefer surgery instead of medication, surgical treatment is considered as second-line treatment. The high hormonal remission and low complication rates after surgery for microprolactinomas suggest that the surgical outcome of endoscopic surgeries may be better than medical therapy in well-selected patients. This study reports a large series of patients with microprolactinoma treated by endoscopic transnasal approach and evaluates the efficiency of surgical treatment. METHODS: Our study is a retrospective cohort analysis of patients with microprolactinoma operated on by an endoscopic transnasal approach between August 1997 and February 2022 by an experienced pituitary surgeon in a single tertiary center. Inclusion criteria for microprolactinoma were based on increased prolactin levels, microadenoma (<10 mm in diameter) on pituitary magnetic resonance imaging, and histopathologically verified lactotroph adenoma. RESULTS: The mean follow-up was 74.90 months (range, 6-207). The postoperative day 1 remission rate was 85.7% and the long-term remission rate was 74.3%. The long-term remission rates of the patients in the preference group were significantly higher than those of the patients in the resistant or intolerance group (P = 0.002). Patients who used dopamine agonists for more than 3 years had a lower remission rate compared with patients who used dopamine agonists for a shorter period or who did not use it (P = 0.01). The surgical complication rate was 4.76%. CONCLUSIONS: According to our findings, endoscopic transnasal surgery performed by an experienced neurosurgeon in well-selected patients with microprolactinoma can be offered with cure rates superior to medical therapy and may be an alternative first-line treatment option to dopamine agonists.

Differentiation of pure cystic sellar lesions on magnetic resonance imaging.

BACKGROUND AND PURPOSE: Cystic pituitary adenomas and cystic craniopharyngiomas may mimic Rathke cleft cysts when there is no solid enhancing component on magnetic resonance imaging (MRI). This study aims to investigate the efficiency of MRI findings in differentiating Rathke cleft cysts from pure cystic pituitary adenoma and pure cystic craniopharyngioma. MATERIALS AND METHODS: 109 patients were included in this study (56 Rathke cleft cysts, 38 pituitary adenomas, and 15 craniopharyngiomas). Preoperative magnetic resonance images were evaluated using 9 imaging findings. These findings include intralesional fluid-fluid level, intralesional septations, midline /off-midline location, suprasellar extension, an intracystic nodule, a hypointense rim on T2-weighted images, ≥ 2 mm thickness of contrast-enhancing wall, T1 hyperintensity and T2 hypointensity. p < 0.01 was considered statistically significant. RESULTS: There was a statistically significant difference among groups for these 9 findings. Intracystic nodule and T2 hypointensity were the most specific MRI findings in differentiating Rathke cleft cyst from the others (98.1% and 100%, respectively). Intralesional septation and thick contrast-enhancing wall were the most sensitive MRI findings ruling out Rathke cleft cysts with 100% sensitivity. CONCLUSION: Rathke cleft cysts can be distinguished from pure cystic adenoma and craniopharyngioma with the presence of an intracystic nodule, T2 hypointensity, the absence of the thick contrast-enhancing wall, and absence of intralesional septations.

Retinal vascular and structural recovery analysis by optical coherence tomography angiography after endoscopic decompression in sellar/parasellar tumors.

We assessed the potential retinal microcirculation alterations for postoperative visual recovery in sellar/paraseller tumor patients with Optical Coherence Tomography Angiography (OCT-A). Two hundred ten eyes with sellar/parasellar tumor for which preoperative and postoperative (3 months) MRI Scans, Visual Acuity Test, Optical Coherence Tomography (OCT), OCT-A and, Visual Field Test data were available, besides 92 healthy eyes were evaluated. In the preoperative phase, significant reductions were observed in retinal vascular densities in various regions, including the Superficial Retinal Capillary Plexus (SRCP) (whole: p < 0.001, fovea: p = 0.025, parafovea: p < 0.001), Deep Retinal Capillary Plexus (DRCP) (whole: p < 0.001, fovea: p = 0.003, parafovea: p < 0.001), Peripapillary Vascular Density (PVD) (whole: p = 0.045, peripapillary: p < 0.001, nasal: p < 0.001, inferior: p < 0.001, temporal: p < 0.001), and Retinal Nerve Fiber Layer (RNFL) (nasal: p = 0.024, inferior: p < 0.001, temporal: p < 0.001, superior: p < 0.001) compared to the healthy control group. After surgery, the postoperative data of patients without chiasmal distortion were compared to their preoperative data. In the postoperative evaluation, significant increases were observed in vascular densities in patients without chiasmal distortion in the SRCP (whole: p < 0.001, parafovea: p = 0.045), DRCP (whole: p = 0.007, fovea: p = 0.006, parafovea: p = 0.040), PVD (peripapillary: p = 0.010, inferior: p < 0.001, temporal: p < 0.001, superior: p < 0.001), and RNFL (nasal: p = 0.011, inferior: p = 0.034, temporal: p = 0.046, superior: p = 0.011). Furthermore, significant associations were observed in the ROC analysis between the postoperative Visual Field Mean Deviation (VFMD) and SRCP (whole AUC = 0.793, p < 0.001, cut-off = 51.45, parafovea AUC = 0.820, p < 0.001, cut-off = 53.95), DRCP (whole AUC = 0.818, p < 0.001, cut-off = 55.95, parafovea AUC = 0.820, p < 0.001, cut-off = 59.05), PVD (temporal AUC = 0.692, p < 0.001, cut-off = 55.10), and RNFL (whole AUC = 0.690, p = 0.001, cut-off = 119.5, inferior AUC = 0.712, p < 0.001, cut-off = 144.75). These findings indicate a potential role of pre and post-operative OCT-A measurements in the assessment of surgical timing and postoperative visual recovery in patients with or without optic chiasm distortion.

Investigation of Demyelination and Remyelination Processes of the Compressed Optic Chiasm: An Experimental Model.

AIM: To demonstrated demyelination and remyelination of the optic nerve histologically by electron microscopy in an experimental model similar to the compression of pituitary adenomas on the optic chiasm. MATERIAL AND METHODS: The rats were fixed to a stereotaxic device under deep anesthesia, and a balloon catheter was placed under the optic chiasm through a burr hole which was in front of the bregma in accordance with the brain atlas of rats. The animals were divided into five groups (n=8): control, mild compression demyelination, severe compression demyelination, mild compression remyelination, severe compression remyelination. The fine structures of the tissues obtained were evaluated using electron microscopy. RESULTS: We found a significant difference in the severity of degeneration when comparing group 1 with group 5 (p < 0.001); there was no degeneration in group 1 rats and severe degeneration in all of the group 5 rats. Oligodendrocytes were found in all rats in group 1 and none of the rats in no group 2. The nuclei were preserved in the group 1 rats but damaged in all of the group 5 rats. There were no lymphocytes or erythrocytes in group 1 and all positives in group 5. CONCLUSION: This technique, which induced degeneration without causing damage to the optic nerve with toxic or chemical agents, revealed Wallerian degeneration similar to tumoral compression. After compression relief, the optic nerve remyelination process can be better understood, particularly for sellar lesions. In our opinion, this model may guide future experiments to identify protocols to induce and accelerate remyelination.

Outcomes of Endoscopic Transsphenoidal Approach for More Aggressive Pediatric Pituitary Adenomas: Early- and Late-Term Results from a Single Center Experience.

OBJECTIVE: Pediatric pituitary adenomas are rare lesions and account for approximately 3% of all supratentorial tumors in children. There is a paucity of reports on endoscopic transsphenoidal surgery in children. The aim of this study was to assess the early/late outcomes of endoscopic pediatric pituitary adenoma surgery at a high-volume tertiary center, as well as to characterize the factors associated with aggressive growth, including the histopathological features. METHODS: Between August 1997 and June 2022, a total of 3256 patients underwent endoscopic transsphenoidal surgery for pituitary adenoma at the Department of Neurosurgery and Pituitary Research Center of the Kocaeli University School of Medicine. Of these, 70 (2.1%) pediatric patients (25 males, 45 females) (age ≤18 years) with a pathological diagnosis of pituitary adenoma were retrospectively reviewed. RESULTS: The mean age of patients was 15.5 ± 2.3 years. Among the hormone-secreting adenomas, 19 (34.5%) were adrenocorticotrophic hormone secreting, 13 (23.6%) were growth hormone secreting, 19 (34.5%) were prolactin secreting, and 4 (7.2%) were both growth hormone-prolactin secreting. Gross total resection was achieved in 93.3% of nonfunctional tumors. The early/late surgical remission rates for hormone-secreting adenomas were 61.5%/46.1% (mean follow-up: 63.7 ± 49.3 months) for acromegaly, 78.9%/68.4% (47.8 ± 51.0 months) for Cushing disease, 57.8%/31.5% (72.2 ± 59.5 months) for prolactinoma, and 25%/25% (35.2 ± 31.4 months) for growth hormone-prolactin-secreting adenomas. Five sparsely granulated corticotroph tumors, 5 sparsely granulated somatotroph tumors, and 11 densely granulated lactotroph tumors were classified as aggressive histopathological subtypes. CONCLUSIONS: The unique characteristics of the pediatric population and the aggressiveness of the disease in this population pose considerable therapeutic challenges. To increase treatment success, current adjuvant therapies that are appropriate for the morphological and biological characteristics of the tumor are required in addition to surgical treatment.

Endoscopic approach for giant pituitary adenoma: clinical outcomes of 205 patients and comparison of two proposed classification systems for preoperative prediction of extent of resection.

OBJECTIVE: Giant pituitary adenoma is considered a challenging pathology for surgery owing to its complications and low resection rate. In this study, the authors present their experience of using the endoscopic endonasal approach to treat patients with giant pituitary adenoma, and they aimed to develop a classification system for prediction of extent of resection. METHODS: The institutional medical records of patients diagnosed with giant pituitary adenoma who underwent endoscopic endonasal transsphenoidal surgery between August 1997 and December 2019 were retrospectively reviewed. Surgical and clinical outcomes were evaluated in detail. The effects of tumor characteristics on extent of resection were analyzed. The findings were used to develop two classification systems that could preoperatively predict extent of resection. Morphological score was based on tumor characteristics, and landmark-based classification was defined according to surgical zones based on neurovascular landmarks. The effects of change in surgical strategy, which aimed to maximize tumor resection and capsule dissection, on rates of resection and complications were evaluated before and after 2017. RESULTS: This study included 205 patients, with a mean patient age of 46.95 years and mean preoperative tumor diameter of 46.56 mm. Gross-total resection (GTR) was achieved in 35.12% of patients, near-total resection (NTR) in 39.51%, and subtotal resection (STR) in 25.36%. Extent of resection differed significantly between the grades and zones of the classification systems (p < 0.001 for both). Among patients with grade 3 tumor, 75.75% of patients achieved STR, 21.21% achieved NTR, and 3.03% achieved GTR. Among patients with zone 3 tumor, 65.75% achieved STR, 32.87% achieved NTR, and 1.36% achieved GTR. Both grade 3 and zone 3 indicated limited extent of resection. The mean (range) follow-up duration was 50.16 (9-247) months. Postoperative recovery of at least one hormone axis was seen in 15.24% of patients with pituitary deficiency, and development of new hormonal deficiency was observed in 22.43% of patients. Complications included permanent diabetes insipidus (7.80%), cerebrospinal fluid leakage (3.90%), postoperative apoplexy (3.90%), meningitis (3.41%), and epistaxis (3.41%). The surgical mortality rate was 1.46%. Among 85 patients treated before 2017, 27.05% of patients achieved GTR, 37.64% achieved NTR, and 35.29% achieved STR; among 120 patients treated after 2017, 40.83% achieved GTR, 40.83% achieved NTR, and 18.33% achieved STR. Seven patients in the pre-2017 cohort had postoperative apoplexy versus only 1 patient in the post-2017 cohort. There were no statistically significant differences between the two periods in terms of the incidence rates of other complications. CONCLUSIONS: Capsule dissection and GTR are valuable for preventing serious complications and reducing recurrence of giant adenoma. Treatment of giant pituitary adenoma may be better managed with the help of a classification system that provides information about extent of resection that can be achieved with an endoscopic approach.

May the SAGIT® instrument be used as a preoperative prognostic tool in patients with acromegaly?

BACKGROUND: The SAGIT® instrument has been developed for acromegaly to assist clinicians in staging the disease accurately, assessing the response to therapy, and adjusting the treatment. We aimed to evaluate the preoperative utility of the SAGIT® instrument and to discover a cut-off value for predicting the surgery outcome and long-term prognosis of patients with acromegaly. METHODS: A total of 832 patients with acromegaly were identified from the medical record system. Acromegaly diagnosis was confirmed by elevated IGF-1 levels according to the age-adjusted upper limit of normal, lack of suppression of GH concentration to <0.4 µg/L following a 75 g oral glucose tolerance test, and the existence of a pituitary adenoma demonstrated by MRI. The SAGIT® instrument comprises five key components of acromegaly: signs and symptoms (S), associated comorbidities (A), GH levels (G), IGF-1 levels (I), and the features of the tumor (T). The initial postoperative remission was evaluated 3 months after surgery. RESULTS: A final cohort of 132 patients has been included in our study. Median preoperative SAGIT scores were significantly different (10.00 [9.00 - 11.00] to 11.00 [10.00 - 13.00], [p = 0.002]) between patients who achieved initial remission at 3 months and those who were not in remission. The threshold SAGIT score distinguishing between initial remission and nonremission groups was 10 with an AUC of 0.660 (p < 0.001). CONCLUSIONS: In our retrospective cohort study, the findings suggested that the SAGIT® instrument may be a beneficial preoperative tool to predict the initial remission postoperatively and long-term prognosis of the patients with acromegaly.

The Endoscopic Endonasal Transsphenoidal Approach for Thyrotropin-Secreting Pituitary Adenomas: Single-Center Experience and Clinical Outcomes of 49 Patients.

OBJECTIVE: To analyze surgical outcomes and tumor characteristics of 49 patients with thyrotropin-secreting pituitary adenoma, a rare functional pituitary adenoma subtype with challenging surgery, who underwent endoscopic endonasal transsphenoidal surgery. METHODS: In this single-center study, clinical, radiological, surgical, and endocrinological data of 49 patients diagnosed with thyrotropin-secreting pituitary adenoma were retrospectively reviewed. RESULTS: Mean tumor size was 21.12 mm (6 microadenomas, 41 macroadenomas, 2 giant adenomas). Cavernous sinus invasion was present in 12 (24.48%) patients. Tumor consistency was firm in 23 (46.93%) patients. Plurihormonal secretion characteristics were present in 9 patients (5 growth hormone + thyrotropin and 4 growth hormone + prolactin + thyrotropin). Mean follow-up duration was 51.73 months. Of the cases with firm tumors, 14 patients had a history of antithyroid drug use; there was no statistically significant correlation between the antithyroid medication and the firmness of the tumor. Gross total resection was achieved in 32 (65.30%) cases, near-total resection was achieved in 14 (28.57%) cases, and subtotal resection was achieved in 3 (6.12%) cases. The analysis showed that the negative effect of >2 cm tumor size and cavernous sinus invasion on resection rate was statistically significant (P < 0.001). Although early remission was achieved in 33 (67.34%) patients, 44 (89.79%) patients were in euthyroid state at >3 months' follow-up. Complications were 4 new-onset pituitary deficiencies, 3 cases of permanent diabetes insipidus, 1 thyrotoxic crisis, and 1 cerebrospinal fluid leak. CONCLUSIONS: Endoscopic endonasal transsphenoidal surgery is the first-line treatment in thyrotropin-secreting pituitary adenoma and should be performed in a tertiary center. Gross total resection is the goal, and early diagnosis is essential for surgical success.

Extended endoscopic transphenoidal approach for tuberculum sellae meningiomas.

PURPOSE: Removal of tuberculum sella (TS) meningiomas is traditionally performed through transcranial approaches. Wide use of the endoscope in transphenoidal pituitary surgery is recently accessible through the tuberculum sellae with an endoscope-assisted or purely endoscopic technique. Extended endoscopic approach is an important and alternative route for meningiomas, which are located on the midline originating from the tuberculum sella. However, cerebrospinal fluid (CSF) leakage is an important problem in extended endoscopic approaches. In this report, we discuss surgical limitations and nuances of endoscopic transphenoidal approach from a retrospective analysis of nine patients with TS meningiomas. METHODS: Endoscopic transphenoidal approach was performed for seven women and two men (mean age, 51.1 years; age range, 32-78 years) with TS meningiomas between July 2007 and March 2010 in the Department of Neurosurgery, Kocaeli, Turkey. RESULTS: Total removal was achieved in six of nine patients. An improvement of the preoperative visual deficits was observed in six of the nine patients. Multilayer closure was performed for reconstruction, and lumbar external drainage was used for all patients for 3-5 days. CSF leakage was not seen in any of the patients after the operation and removal of the drainage. CONCLUSION: Endoscopic extended transphenoidal approach is still not a standardized procedure for TS meningiomas, but it may be considered as an alternative procedure in selected cases.