Contemporary neurosurgical techniques for pituitary tumor resection

Clinical study on the selection of endoscopes and microscopes for transsphenoidal surgery of non-aggressive pituitary macroadenoma and microadenoma and the influencing factors of hyposmia after endoscopic transsphenoidal surgery

Background and objective

Transsphenoidal surgery, including endoscopic and microscopic resection, is the first choice of treatment for pituitary tumors. With the widespread application of neuroendoscopy in recent decades, there has been a trend to replace microscopes. In clinical practice, we have found that in transsphenoidal surgery for non-invasive microadenomas and macroadenomas, microscopy can achieve a higher total resection rate, shorter operation time, lower incidence of postoperative complications, and faster recovery of olfaction. This study aimed to explore the selection of endoscopes and microscopes for non-aggressive transsphenoidal surgery for pituitary adenomas and the factors affecting olfactory recovery.

Methods

From August 2019 to October 2022, 93 patients with non-aggressive microadenomas and macroadenomas via the transsphenoidal approach were selected from the First Affiliated Hospital of Harbin Medical University and treated with rich experience in pituitary tumor subspecialty microscopy and endoscopic surgery. Different surgical methods were used to divide the patients into microscopic (n = 35) and endoscopic (n = 58) groups. The total tumor removal rate, intraoperative blood loss, operation time and cost, postoperative hospital stay, recovery of visual function, postoperative changes in hormone levels, complication rate, and recovery from complications 3 months after the operation were compared between the two groups.

Results

There were no significant differences in the tumor removal rate, postoperative visual acuity, and visual field recovery between the two groups (p > 0.05). There was a significant difference in the recovery rate of olfactory function between the two groups 3 months after the operation (p < 0.05), and there was no significant difference in the incidence of other complications (p > 0.05); Compared with the two groups, the microscope group had shorter operation time, longer postoperative hospital stay, less average operation cost and less blood loss, and the difference was statistically significant (p < 0.05). The position of the nasal septum mucosal flap incision was a risk factor for hyposmia 3 months after the operation.

Conclusion

Microsurgery and endoscopic surgery are suitable surgical treatments for nonaggressive microadenomas and macroadenomas. The total tumor removal and postoperative hormone remission rates of the two surgical methods were approximately the same. However, the microsurgery group had a shorter operation time, less intraoperative blood loss, faster olfactory function recovery, and a lower average operation cost. The position of the nasal septal mucosal flap incision was a risk factor for hyposmia at 3 months postoperatively. Hyposmia is less likely to occur when the superior edge of the nasal septal mucosal flap incision is not higher than the lower edge of the ipsilateral superior turbinate.

Improved nasal recovery and intact olfactory function after a transseptal approach for endoscopic endonasal transsphenoidal adenomectomy: A retrospective analysis

Objectives

Endoscopic endonasal transsphenoidal adenomectomy (TSA) is the most frequently performed skull base surgery, and researchers have recently focused on preserving nasal function. The endoscopic transseptal approach is a promising procedure due to its reduced injury to the nasal mucosa; however, there are no studies comparing rhinological and neurosurgical outcomes concurrently with the standard endoscopic transnasal approach. Therefore, we conducted this study to investigate whether the transseptal approach could reduce nasal morbidities with comparable neurosurgical outcomes.

Methods

We retrospectively reviewed 25 patients who underwent endoscopic endonasal transseptal TSA for pituitary adenoma without encasement of internal carotid artery from January 2019 to December 2020. Another 25 patients who received transnasal approach from January 2017 to December 2018 were selected as controls. Patients with diseases affecting the nasal cavity/olfaction or usage of a nasoseptal flap were excluded for a better comparison of the two procedures. We collected data from radiological studies, endocrine studies, endoscopic evaluations, 22-item sinonasal outcome tests (SNOT-22) and Top International Biotech Smell Identification Test (TIBSIT) for comparison.

Results

Lower postoperative SNOT-22 and Lund-Kennedy endoscopic scores were observed in the transseptal group. The effect size of differences were classified as large effect (The absolute value of Cohen's d > 0.8). Nevertheless, the TIBSIT scores were not significantly different. The rates of gross total resection, recovery of hormonal abnormalities, and complications were not significantly different. After controlling possible confounding factors using multivariate analysis, the endoscopic transseptal approach remained an independent factor for lower SNOT-22 scores and Lund-Kennedy endoscopic scores.

Conclusions

The endoscopic transseptal approach provides improved recovery of nasal mucosa and intact olfaction without compromising neurosurgical outcomes.

Level of Evidence

2b.

Treatment of hyperprolactinemia: A single-institute experience

BACKGROUND

Dopamine agonists such as bromocriptine and cabergoline have been found to be an effective treatment for hyperprolactinemia, not only inducing adenoma shrinkage but also lowering serum prolactin levels. Among known dopamine agonists, cabergoline is the drug of choice due to its enhanced tolerability compared with bromocriptine. This study aimed to evaluate cabergoline's effectiveness, along with transsphenoidal surgery, in the treatment of hyperprolactinemia.

METHODS

We retrieved all patients with a diagnosis of prolactinoma who were treated in our hospital during 2000-2018. A total of 208 patients were enrolled in the analysis after applying exclusion criteria. Patients were divided into four groups according to the treatments received. The demographic data, dosage and duration of cabergoline, and serum prolactin levels at different time points were collected for analysis.

RESULTS

Normalization was achieved in 59 patients (83.10%) within a short median duration of 2.80 months among those treated with cabergoline only. Although cabergoline alone was effective and well-tolerated, our data showed that long-term remission rates were more favorable when surgery was involved. The long-term remission rate of all patients enrolled was 53.8% (112 patients among 208 patients). The long-term remission rates for the different treatment groups were 17.8% (8 of 45 patients) in Group 1 (Operation→Drug), 83.3% (5 of 6 patients) in Group 2 (Drug→Operation), 79.0% (68 of 86 patients) in Group 3 (Operation only), and 43.7% (31 of 71 patients) in Group 4 (Drug only).

CONCLUSION

Cabergoline has been demonstrated to be effective and should be considered as a first-line treatment for hyperprolactinemia. In our study, transsphenoidal surgery was also demonstrated to achieve good results compared with medical treatment. Surgical intervention may resurface as an alternative first-line treatment. When used in combination with cabergoline, surgery offers a higher disease remission rate than either drug or operation alone.

Improvement in the Quality of Early Postoperative Course After Endoscopic Transsphenoidal Pituitary Surgery: Description of Surgical Technique and Outcome

Objective: The endoscopic transsphenoidal pituitary surgery has gained popularity and has shown excellent results with a more comfortable postoperative course. However, the quality of the early postoperative course is not well-established in endoscopic transsphenoidal pituitary surgery. We hypothesized that the quality of the early postoperative course would be improved when an enhanced recovery after surgery (ERAS) protocol and minimally invasive endoscopic transsphenoidal pituitary surgery is implemented.

Methods: We implemented a perioperative management ERAS protocol for endoscopic transsphenoidal pituitary surgery by an experienced surgeon (Yuehui Ma) in our department from January 2018. From then the endoscopic transsphenoidal pituitary surgery was implemented with a minimally invasive technique, such as bony sella reconstruction and partial nasal packing. We compared the results of 78 endoscopic transsphenoidal pituitary surgery cases during the initiation of the ERAS protocol and minimally invasive technique implementation: 37 cases in the control group and 41 cases in the ERAS group. Outcomes assessed included the effectiveness and security of surgery, postoperative hospital length of stay (LOS), and postoperative status on postoperative day 1 (POD1).

Results: Postoperative status on POD1, such as nasal ventilation, out of bed, headache score, and liquid supplement, had significant improvement (P < 0.05). The median postoperative LOS decreased from 8 days in the control group to 3 days in the ERAS group (P < 0.05). The ERAS group had better economic benefit with fewer hospital charges (P < 0.05). There was no difference in the early postoperative diabetes insipidus and 30-day readmission for epistaxis, hyponatremia, or other complications between the two groups.

Conclusion: The quality of the early postoperative course was improved when a neurosurgical ERAS protocol and minimally invasive endoscopic transsphenoidal pituitary surgery with partially nasal packing were implemented. Endoscopic transsphenoidal pituitary day surgery could be recommended in some classes of patients though further evaluation in large case studies is warranted.

Folate Receptor Near-Infrared Optical Imaging Provides Sensitive and Specific Intraoperative Visualization of Nonfunctional Pituitary Adenomas

BACKGROUND

Surgical resection is the primary treatment for nonfunctional (NF) pituitary adenomas, but gross-total resection is difficult to achieve in all cases. NF adenomas overexpress folate receptor alpha (FRα).

OBJECTIVE

To test the hypothesis that we could target FRα for highly sensitive and specific intraoperative detection of NF adenomas using near-infrared (NIR) imaging.

METHODS

Fourteen patients with NF pituitary adenoma were infused with the folate analog NIR dye OTL38 preoperatively. NIR fluorescence signal-to-background ratio (SBR) was recorded for each tumor during resection of the adenomas. Extent of surgery was not modified based on the presence or absence of fluorescence. Immunohistochemistry was performed to assess FRα expression in all specimens. Magnetic resonance imaging (MRI) was performed postoperatively to assess residual neoplasm.

RESULTS

Nine adenomas overexpressed FRα and fluoresced with a NIR SBR of 3.2 ± 0.52, whereas the 5 non-FRα-overexpressing adenomas fluoresced with an SBR of 1.5 ± 0.21. Linear regression demonstrated a significant correlation between intraoperative SBR and the FRα expression (P-value < .001). Analysis of 14 margin samples revealed that the surgeon's impression of the tissue had 83% sensitivity, 100% specificity, 100% positive predictive value, and 89% negative predictive value, while NIR fluorescence had 100% for all values. NIR fluorescence accurately predicted postoperative MRI results in 78% of FRα-overexpressing patients.

CONCLUSION

Preoperative injection of folate-tagged NIR dye provides strong signal and visualization of NF pituitary adenomas. It is 100% sensitive and specific for detecting margin neoplasm and can predict postoperative MRI findings. Our results suggest that NIR fluorescence may be superior to white-light visualization alone and may improve resection rates in NF pituitary adenomas.

Indocyanine-Green for Fluorescence-Guided Surgery of Brain Tumors: Evidence, Techniques, and Practical Experience

The primary treatment for brain tumors often involves surgical resection for diagnosis, relief of mass effect, and prolonged survival. In neurosurgery, it is of utmost importance to achieve maximal safe resection while minimizing iatrogenic neurologic deficit. Thus, neurosurgeons often rely on extra tools in the operating room, such as neuronavigation, intraoperative magnetic resonance imaging, and/or intraoperative rapid pathology. However, these tools can be expensive, not readily available, time-consuming, and/or inaccurate. Recently, fluorescence-guided surgery has emerged as a cost-effective method to accurately visualize neoplastic areas in real-time to guide resection. Currently, 5-aminolevulinic-acid (5-ALA) remains the only fluorophore that has been approved specifically for fluorescence-guided tumor resection. Its use has demonstrated improved resection rates and prolonged progression-free survival. However, protoporphyrin-IX, the metabolic product of 5-ALA that accumulates in neoplastic cells, fluoresces in the visible-light range, which suffers from limited tissue penetration and significant auto-fluorescence. Near-infrared fluorescence, on the other hand, overcomes these problems with ease. Since 2012, researchers at our institution have developed a novel technique using indocyanine-green, which is a well-known near-infrared fluorophore used traditionally for angiography. This Second-Window-ICG (SWIG) technique takes advantage of the increased endothelial permeability in peritumoral tissue, which allows indocyanine-green to accumulate in these areas for intraoperative visualization of the tumor. SWIG has demonstrated utility in gliomas, meningiomas, metastases, pituitary adenomas, chordomas, and craniopharyngiomas. The main benefits of SWIG stem from its highly sensitive detection of neoplastic tissue in a wide variety of intracranial pathologies in real-time, which can help neurosurgeons both during surgical resections and in stereotactic biopsies. In this review of this novel technique, we summarize the development and mechanism of action of SWIG, provide evidence for its benefits, and discuss its limitations. Finally, for those interested in near-infrared fluorescence-guided surgery, we provide suggestions for maximizing the benefits while minimizing the limitations of SWIG based on our own experience thus far.

A small 3D-printing model of macroadenomas for endoscopic endonasal surgery

PURPOSE

This paper examines the application of 3D printing technology in the endoscopic endonasal approach for the treatment of macroadenomas.

METHODS

We have retrospectively analysed 20 patients who diagnosed with macroadenoma underwent endoscopic transsphenoidal surgery in Wuhan Union hospital from January 2017 to May 2017. Among the 20 patients, 10 patients received the service of 3D printing technology preoperatively. The data of 3D processing and clinical result were recorded for further evaluation.

RESULTS

The 10 patients who received the service had a successful 3D printed model of their tumors, it shows the anatomy of sphenoid sinus, tumor location which were in good agreement with our intraoperative observations. The 10 patients who received the service had a less operation time (127.0 ± 15.53 vs. 143.40 ± 17.89), blood loss (159.90 ± 12.31 vs. 170.00 ± 29.06) and less postoperative complication rate (20% vs. 40%). the design time of the 3D images varies 2 h 10 min to 4 h 32 min. the printing time of the 3D models varies 10 h 12 min to 22 h 34 min.

CONCLUSIONS

The use of 3D printing technology has unquestionable potential applications to endoscopic endonasal approach for macroadenomas, in particular reflecting the complicated anatomy of sphenoid sinus and tumor location. Owing to the advantages of 3D printing technology, it may help the patients get a good prognosis.

Intraoperative near-infrared imaging with receptor-specific versus passive delivery of fluorescent agents in pituitary adenomas

OBJECTIVE

Intraoperative molecular imaging with tumor-targeted fluorescent dyes can enhance resection rates. In contrast to visible-light fluorophores (e.g., 5-aminolevulinic-acid), near-infrared (NIR) fluorophores have increased photon tissue penetration and less contamination from tissue autofluorescence. The second-window ICG (SWIG) technique relies on passive accumulation of indocyanine green (ICG) in neoplastic tissues. OTL38, conversely, targets folate receptor overexpression in nonfunctioning pituitary adenomas. In this study, we compare the properties of these 2 modalities for NIR imaging of pituitary adenomas to better understand the potential for NIR imaging in neurosurgery.

METHODS

A total of 39 patients with pituitary adenomas were enrolled between June 2015 and January 2018 in 2, sequential, IRB-approved studies. Sixteen patients received systemic ICG infusions 24 hours prior to surgery, and another 23 patients received OTL38 infusions 2-3 hours prior to surgery. NIR fluorescence signal-to-background ratio (SBR) was recorded during and after resection. Immunohistochemistry was performed on the 23 adenomas resected from patients who received OTL38 to assess expression of folate receptor-alpha (FRα).

RESULTS

All 16 adenomas operated on after ICG administration demonstrated strong NIR fluorescence (mean SBR 4.1 ± 0.69 [SD]). There was no statistically significant difference between the 9 functioning and 7 nonfunctioning adenomas (p = 0.9). After administration of OTL38, the mean SBR was 1.7 ± 0.47 for functioning adenomas, 2.6 ± 0.91 for all nonfunctioning adenomas, and 3.2 ± 0.53 for the subset of FRα-overexpressing adenomas. Tissue identification with white light alone for all adenomas demonstrated 88% sensitivity and 90% specificity. SWIG demonstrated 100% sensitivity but only 29% specificity for both functioning and nonfunctioning adenomas. OTL38 was 75% sensitive and 100% specific for all nonfunctioning adenomas, but when assessment was limited to the 9 FRα-overexpressing adenomas, the sensitivity and specificity of OTL38 were both 100%.

CONCLUSIONS

Intraoperative imaging with NIR fluorophores demonstrates highly sensitive detection of pituitary adenomas. OTL38, a folate-receptor-targeted fluorophore, is highly specific for nonfunctioning adenomas but has no utility in functioning adenomas. SWIG, which relies on passive diffusion into neoplastic tissue, is applicable to both functioning and nonfunctioning pituitary adenomas, but it is less specific than targeted fluorophores. Thus, targeted and nontargeted NIR fluorophores play important, yet distinct, roles in intraoperative imaging. Selectively and intelligently using either agent has the potential to greatly improve resection rates and outcomes for patients with intracranial tumors.

Folate receptor overexpression can be visualized in real time during pituitary adenoma endoscopic transsphenoidal surgery with near-infrared imaging

OBJECTIVE Pituitary adenomas account for approximately 10% of intracranial tumors and have an estimated prevalence of 15%-20% in the general US population. Resection is the primary treatment for pituitary adenomas, and the transsphenoidal approach remains the most common. The greatest challenge with pituitary adenomas is that 20% of patients develop tumor recurrence. Current approaches to reduce recurrence, such as intraoperative MRI, are costly, associated with high false-positive rates, and not recommended. Pituitary adenomas are known to overexpress folate receptor alpha (FRα), and it was hypothesized that OTL38, a folate analog conjugated to a near-infrared (NIR) fluorescent dye, could provide real-time intraoperative visual contrast of the tumor versus the surrounding nonneoplastic tissues. The preliminary results of this novel clinical trial are presented. METHODS Nineteen adult patients who presented with pituitary adenoma were enrolled. Patients were infused with OTL38 2-4 hours prior to surgery. A 4-mm endoscope with both visible and NIR light capabilities was used to visualize the pituitary adenoma and its margins in real time during surgery. The signal-to-background ratio (SBR) was recorded for each tumor and surrounding tissues at various endoscope-to-sella distances. Immunohistochemical analysis was performed to assess the FRα expression levels in all specimens and classify patients as having either high or low FRα expression. RESULTS Data from 15 patients (4 with null cell adenomas, 1 clinically silent gonadotroph, 1 totally silent somatotroph, 5 with a corticotroph, 3 with somatotrophs, and 1 somatocorticotroph) were analyzed in this preliminary analysis. Four patients were excluded for technical considerations. Intraoperative NIR imaging delineated the main tumors in all 15 patients with an average SBR of 1.9 ± 0.70. The FRα expression level of the adenomas and endoscope-to-sella distance had statistically significant impacts on the fluorescent SBRs. Additional considerations included adenoma functional status and time from OTL38 injection. SBRs were 3.0 ± 0.29 for tumors with high FRα expression (n = 3) and 1.6 ± 0.43 for tumors with low FRα expression (n = 12; p < 0.05). In 3 patients with immunohistochemistry-confirmed FRα overexpression (2 patients with null cell adenoma and 1 patient with clinically silent gonadotroph), intraoperative NIR imaging demonstrated perfect classification of the tumor margins with 100% sensitivity and 100% specificity. In addition, for these 3 patients, intraoperative residual fluorescence predicted postoperative MRI results with perfect concordance. CONCLUSIONS Pituitary adenomas and their margins can be intraoperatively visualized with the preoperative injection of OTL38, a folate analog conjugated to NIR dye. Tumor-to-background contrast is most pronounced in adenomas that overexpress FRα. Intraoperative SBR at the appropriate endoscope-to-sella distance can predict adenoma FRα expression status in real time. This work suggests that for adenomas with high FRα expression, it may be possible to identify margins and to predict postoperative MRI findings.

Transsphenoidal Surgery for Elderly Patients with Acromegaly and Its Outcomes: Comparison with Younger Patients

BACKGROUND

Elderly patients with acromegaly who have comorbidities may increasingly encounter perioperative complications; however, little data are available on the risks and outcomes of surgical treatment in these patients. We aimed to analyze and compare the results of transnasal transsphenoidal surgery (TTS) in elderly and younger patients.

METHODS

Eighty-seven consecutive patients with acromegaly who underwent TTS were included. We divided the patients into elderly (≥65 years) and younger (<65 years) groups and compared clinical characteristics, anesthesia risk, and surgical outcomes in these 2 groups.

RESULTS

The 87 patients included 24 (27.6%) in the elderly group and 63 (73.4%) in the younger group. Preoperative endocrinologic and radiologic assessments showed no significant differences between the 2 groups. Although a grade 3 American Society of Anesthesiologists Physical Status classification was more common in the elderly group (75% vs. 3%; P = 0.00001) owing to the severity of associated diseases, no significant between-group difference in perioperative complications was seen (17% vs. 6%; P = 0.142). Sixteen elderly patients and 45 younger patients achieved endocrinologic remission following surgery (67% vs. 71%; P = 0.426). The incidence rate of postoperative new pituitary deficit was similar in the elderly and younger groups (4% vs. 3%; P = 0.625). Approximately one-third of the elderly patients with diagnosed hypertension or diabetes mellitus tapered their medication after successful tumor removal.

CONCLUSIONS

TTS can be considered a safe treatment for both younger and elderly patients with acromegaly. Successful tumor removal provided a significant improvement in comorbidities even in elderly patients with acromegaly.

Identification and repair of intraoperative cerebrospinal fluid leaks in endonasal transsphenoidal pituitary surgery: surgical experience in a series of 1002 patients

OBJECTIVE Cerebrospinal fluid (CSF) rhinorrhea is among the most common complications following transsphenoidal surgery for sellar region lesions. The aim of this study was to review the authors' institutional experience in identifying, repairing, and treating CSF leaks associated with direct endonasal transsphenoidal operations. METHODS The authors performed a retrospective review of cases involving surgical treatment of pituitary adenomas and other sellar lesions at the University of Southern California between December 1995 and March 2016. Inclusion criteria included all pathology of the sellar region approached via a direct microscopic or endoscopic endonasal transsphenoidal approach. Demographics, pathology, intraoperative and postoperative CSF leak rates, and other complications were recorded and analyzed. A literature review of the incidence of CSF leaks associated with the direct endonasal transsphenoidal approach to pituitary lesions was conducted. RESULTS A total of 1002 patients met the inclusion criteria and their cases were subsequently analyzed. Preoperative diagnoses included pituitary adenomas in 855 cases (85.4%), Rathke's cleft cyst in 94 (9.4%), and other sellar lesions in 53 (5.2%). Lesions with a diameter ≥ 1 cm made up 49% of the series. Intraoperative repair of an identified CSF leak was performed in 375 cases (37.4%) using autologous fat, fascia, or both. An additional 92 patients (9.2%) underwent empirical sellar reconstruction without evidence of an intraoperative CSF leak. Postoperative CSF leaks developed in 26 patients (2.6%), including 13 (1.3% of the overall group) in whom no intraoperative leak was identified. Among the 26 patients who developed a postoperative CSF leak, 13 were noted to have intraoperative leak and underwent sellar repair while the remaining 13 did not have an intraoperative leak or sellar repair. No patients who underwent empirical sellar repair without an intraoperative leak developed a postoperative leak. Eight patients underwent additional surgery (0.8% reoperation rate) for CSF leak repair, and 18 were successfully treated with lumbar drainage or lumbar puncture alone. The incidence of postoperative CSF rhinorrhea in this series was compared with that in 11 other reported series that met inclusion criteria, with incidence rates ranging between 0.6% and 12.1%. CONCLUSIONS In this large series, half of the patients who developed postoperative CSF rhinorrhea had no evidence of intraoperative CSF leakage. Unidentified intraoperative CSF leaks and/or delayed development of CSF fistulas are equally important sources of postoperative CSF rhinorrhea as the lack of employing effective CSF leak repair methods. Empirical sellar reconstruction in the absence of an intraoperative CSF leak may be of benefit following resection of large tumors, especially if the arachnoid is thinned out and herniates into the sella.

Comparative Cost Analysis of Endoscopic versus Microscopic Endonasal Transsphenoidal Surgery for Pituitary Adenomas

Objective  This study presents a comparative analysis of cost efficacy between the microscopic and endoscopic transsphenoidal approaches, evaluating neurological outcome, extent of resection (EOR), and inpatient hospital costs. Design  This study was a retrospective chart review. Setting  This study was conducted at a tertiary care center. Participants  The study group consisted of 68 patients with transsphenoidal surgeries between January 2007 and January 2014. Main Outcome Measures  Two-sample t -tests and Pearson's chi-square test evaluated inpatient costs, quality-adjusted life years (QALYs), volumetric EOR, and neurological outcomes. Results  Total inpatient costs per patient was $22,853 in the microscopic group and less ($19,736) in the endoscopic group ( p  = 0.049). Operating room costs were $5,974 in the microscopic group and lower in the endoscopic group ($5,045; p  = 0.038). Operative time was 203.6 minutes in the microscopic group and 166.3 minutes in the endoscopic group ( p  = 0.032). The QALY score, length of hospital stay, and postoperative outcomes were found to be similar between the two cohorts. Multivariate linear regression modeling suggested that length of stay ( p  < 0.001) and operative time ( p  = 0.008) were important factors that influenced total inpatient costs following transsphenoidal surgery. Conclusion  This study shows that transsphenoidal surgery is more cost effective with the endoscopic approach than with the microscopic approach and depends on efficiency in the operating room as well as reduction in the length of hospitalization.

Clinical characteristics of acromegalic patients with empty sella and their outcomes following transsphenoidal surgery

PURPOSE

To analyze the clinical characteristics of acromegalic patients with empty sella (ES, herniation of the subarachnoid space within the sella turcica) and the impact of ES on transsphenoidal surgery in such patients.

METHODS

Seventy-eight patients, newly diagnosed with acromegaly who underwent transsphenoidal surgery were included. ES was defined as the pituitary gland and adenoma occupying less than 50% of the sella turcica on midsagittal magnetic resonance (MR) imaging.

RESULTS

Twelve patients (15.4%), predominantly female (10 women, p = .047), had ES in preoperative MR imaging. ES patients had smaller mean tumor diameter (6.3 mm) than non-ES patients (11.2 mm, p = .001). In preoperative MR imaging, occult adenoma was found in three (25%) ES and three (4.5%) non-ES patients (p = .044). Intraoperative cerebrospinal fluid (CSF) leakage was more frequent in the ES patients than in the non-ES patients (58.3 vs. 25.8%, p = .024). This led to an increased rate of sellar floor reconstruction using abdominal fat and/or postoperative lumber drainage in the ES patients (ES: 41.7 vs. non-ES: 16.7%, p = .063). Endocrinological remission after surgery was more frequent in the non-ES patients (72.7%) than in the ES patients (58.3%) (p = .248).

CONCLUSIONS

Co-existence of acromegaly with ES is not rare, and is associated with occult adenoma, intra/postoperative CSF leakage, and a worse endocrinological outcome after transsphenoidal surgery; although, the underlying mechanism remains unclear.

Risk Factors and Management of Intraoperative Cerebrospinal Fluid Leaks in Endoscopic Treatment of Pituitary Adenoma: Analysis of 492 Patients

OBJECTIVES

To determine risk factors and management of intraoperative cerebrospinal fluid (CSF) leakage in endoscopic endonasal transsphenoidal pituitary adenoma surgery.

METHODS

We conducted a retrospective review of 492 patients who, between April 2012 and August 2015, underwent endoscopic endonasal transsphenoidal surgeries for resection of pituitary adenoma. A multivariate statistical analysis was performed to investigate the association of some risk factors with intraoperative CSF leakage. Intraoperative CSF leaks were classified as grade 0, no leak observed; grade 1, small leak without obvious diaphragmatic defect; grade 2, moderate leak; or grade 3, large diaphragmatic defect. Repair methods were based on the CSF leak grade.

RESULTS

Intraoperative CSF leakage occurred in 86 cases (17.5%). On univariate analysis, there were 3 factors associated with an increased intraoperative CSF leak rate: 1) repeat surgery (repeat 30.0% vs. primary 16.4%; P = 0.033), 2) consistency of the adenoma (tenacious, 27.3% vs. soft, 13.5%; P = 0.000), and 3) tumor size (22.0 ± 9.7mm vs. 25.4 ± 11.5 mm; P = 0.007). However, on multivariate analysis, only tumor consistency (P = 0.001; odds ratio, 2.379) and tumor size (P = 0.026; odds ratio, 1.032) were independently associated with intraoperative CSF leaks. In the 86 cases with intraoperative CSF leaks, the degree of intraoperative CSF leakage was categorized grade 1 in 30 cases, grade 2 in 25 cases, and grade 3 in 31 cases. Postoperative CSF leak repair failures occurred in 6 cases (1.2%).

CONCLUSIONS

Intraoperative CSF leaks have a propensity to occur in cases with fibrous or large tumors. Once an intraoperative leak is identified, our graded cranial base repair method is safe and reliable.

Complications Related to the Endoscopic Endonasal Transsphenoidal Approach for Nonfunctioning Pituitary Macroadenomas in 300 Consecutive Patients

OBJECTIVE

To analyze complications of endoscopic transsphenoidal surgery (ETS) for nonfunctioning pituitary macroadenomas (NFPAs).

METHODS

A retrospective study of 300 NFPAs was performed. Complications and factors that could influence these complications were analyzed.

RESULTS

Visual and pituitary functions worsened in 2.4% and 13.7% of cases, respectively. Postoperative diabetes insipidus was permanent in 6.2% of cases. Postoperative meningitis occurred in 3.3% of patients. Meningitis was strongly associated with intraoperative cerebrospinal fluid (CSF) leaks (P = 0.01), postoperative CSF leaks (P = 0.0001), and operation times longer than 1 hour (P = 0.023). Detection of Staphylococcus aureus and preoperative treatment with mupirocin in the nostrils did not impact the occurrence of meningitis. Two patients with meningitis died (unique causes of death). Postoperative CSF leaks occurred in 2.7% of cases and were associated with intraoperative CSF leaks (P = 0.007) and permanent diabetes insipidus (P = 0.028). The rate of CSF leak decreased from 4% to 0.8% (P = 0.048) after we moved from a soft to hard reconstruction of the sella. The rate of postoperative epistaxis decreased from 6.7% to 1.25% after we stopped using monopolar coagulation (P = 0.013).

CONCLUSIONS

ETS permits a wide view, allowing good conditions for a satisfactory resection in the majority of NFPAs. Some pitfalls of endoscopy can lead to complications that improve with modification of the operative technique (i.e., CSF leak and postoperative epistaxis). This study confirms an acceptable rate of complications associated with ETS.

Time to Revive the Value of the Pseudocapsule in Endoscopic Endonasal Transsphenoidal Surgery for Growth Hormone Adenomas

OBJECTIVE

To investigate the role of endoscopic endonasal transsphenoidal surgery and the pseudocapsule in the treatment of growth hormone adenomas.

METHODS

The study included 43 patients (age range, 21-64 years) with growth hormone adenomas treated with an endoscopic endonasal approach. We compared the tumor characteristics and surgical outcomes of cases with (group A, 21 cases, from November 2013 to January 2015) and without (group B, 22 cases, from October 2011 to October 2013) extra-pseudocapsule resection.

RESULTS

The preoperative demographics, tumor characteristics, and surgical complications were not significantly different between groups A and B. Postoperative remission without adjuvant therapy was achieved in 18 of 21 cases (85.7%) in group A, which was significantly greater than that observed in group B (12 of 22 cases [54.4%]). In group A, the pseudocapsules were verified by endoscopy and histopathology. The pseudocapsule was removed en bloc with the whole adenoma in only 5 cases (23.8%). For the remaining 16 patients (76.2%), following extra-pseudocapsule dissection, incomplete pseudocapsule removals with intracapsule procedures were achieved.

CONCLUSIONS

The combination of extra-pseudocapsule resection and endoscopy led to a high rate of gross total tumor resection and endocrinologicl remission in acromegalic patients compared with the group with intracapsular resection. Extra-pseudocapsule resection resulted in no additional postoperative complications.

Endoscopic endonasal transsellar approach for laterally extended pituitary adenomas: volumetric analysis of cavernous sinus invasion

PURPOSE

The authors conducted a statistical analysis of surgical results of the endoscopic endonasal transsellar approach to provide quantitative indices for selection of the approach in the treatment of laterally extended pituitary adenomas.

METHODS

Surgical results of 25 patients with laterally extended pituitary adenomas of Knosp grade 3 or 4 were retrospectively analyzed. The removal rate was evaluated by the volumetric change of the lateral tumor compartment.

RESULTS

The transsellar approach was used exclusively in all cases. Gross total removal of the lateral tumor compartment was achieved in 14 (56.0%). Factors affecting the tumor removal through the transsellar approach were lateral tumor volume (p = 0.006), maximal distance to the cavernous sinus outer wall (p = 0.004) and history of previous surgery (p = 0.017). The cut-off values for the lateral tumor volume and maximal distance to the cavernous sinus outer wall predicting the gross total removal were 0.479 ml and 8.1 mm, respectively. The surgical complications of the transsellar approach included each case of anterior lobe function insufficiency and liquorrhea.

CONCLUSIONS

The transsellar approach is adequate for removal of lateral tumor compartment in the majority of cases with laterally extended pituitary adenomas. The tumor compartments dorsal and ventral to the horizontal portion of the intracavernous carotid artery are amenable to the removal. But for removal of the tumor compartment lateral to the carotid siphon requires additional use of the parasellar approach.