Endoscopic endonasal transsphenoidal approach to sellar lesions: a detailed account of our mononostril technique

Sellar metastasis: A rare intraoperative finding - surgical treatment, strategies and outcome

OBJECTIVE

The sellar region, though uncommon for metastatic spread, may become more prevalent due to longer survival of patients with metastatic malignancies. Compression of adjacent vital anatomy can cause disabling symptoms and endocrine disturbances, leading to significant morbidity METHODS: This study analyzed sellar pathologies treated via endonasal approach from January 2011 to December 2021 to assess the incidence of sellar metastases. Patient demographics, presenting symptoms, radiological and histological findings, management, and outcomes were evaluated RESULTS: Among 334 patients treated during the study period, eight (2.3 %) had metastases confirmed histopathologically, with one having a known malignant tumor history. Preoperative imaging suspected malignancy or metastasis in two cases. Diagnosis was unexpectedly confirmed in 57 % of cases. Subtotal resection was achieved in three cases, near-total resection in one. Mean follow-up was 2.4 years, with 71 % mortality CONCLUSIONS: The sellar region can manifest metastatic disease, with sellar symptoms potentially indicating neoplastic disease onset. Rapid hormonal dysfunction or ophthalmoplegia suggests metastasis, even without a known primary. Further meta analysis of reported cases is necessary to determine the incidence and optimal treatment of these rare metastases.

Application of binasal speculum in endoscopic endonasal surgery for lesions in sellar region

Objective

This study aims to access the efficacy of the binasal speculum in endoscopic endonasal surgery by evaluating clinical outcomes and examining its utility through process-based performance measures in both surgeons and assistants.

Methods

A total of 59 patients with lesions in sellar region who underwent endoscopic endonasal surgery with the binasal speculum between September 2020 and March 2023 were included in this study. We assessed the extent of resection and documented postoperative nasal condition. Both surgeons and assistants completed post-use surveys to exam the utility of the binasal speculum and provide an overall grading.

Results

Gross total resection (GTR) was successfully achieved in 94.9% (56/59) of patients, with subtotal resection (STR) observed in 5.1% (4/59) of patients. Intraoperative cerebrospinal fluid (CSF) leakage occurred in 23.7% (14/59) of cases, and nasoseptal flap (NSF) reconstruction was required in 55.9% (33/59) of cases. The nasal airway patency rapidly recovered within 14 days in a significant majority of patients (94.9%, 56/59). Moreover, olfactory function was regained within three months postoperatively by 91.5% (54/59) of patients. The overall post-use survey mean score was 26.4. Specifically, surgeons had a mean score of 26.5, while assistants had a slightly lower mean score of 26.2. The mean overall grading for the binasal speculum was 3. Both surgeons and assistants provided a mean overall grading of 3.

Conclusion

The binasal speculum provides nasal mucosa protection and reduces the risk of an endoscopic lens clouded by mucosa or blood. It plays a crucial role in accurate guidance and facilitates the swift delivery of surgical instruments, particularly in left-blinded nasal cavities. The binasal speculum reduces the learning curve, especially for endoscopic surgeons with limited experience, while enhancing collaboration and coordination between surgeons and assistants during surgery. Both surgeons and assistants rated the overall utility of the binasal speculum as "excellent."

Comparison of the Novel Two-Hand Technique Using the Saraj Endocath with the Traditional Three-Hand Technique in Transnasal Endoscopic Pituitary Surgery: An Innovation for the Future

BACKGROUND

Endoscopic surgery has become the preferred treatment of sellar lesions because of its minimally invasive nature. Visualization is frequently obscured as a result of the frequent contact of the lens with blood and tissue debris. We seek to alleviate these problems and increase the efficiency and safety of neuroendoscopic surgery by introducing a new device (Saraj Endocath) combining the major function of suction with the endoscope.

METHODS

A total of 75 patients with pituitary macroadenoma who were eligible for transnasal transsphenoidal endoscopic excision were included in the study between January 2020 and January 2023. Forty-one patients were operated on by the traditional 3-hand technique and 34 patients were operated on using the Saraj Endocath. The duration of surgery, in-out frequency of the endoscope, number of wipes needed to clean the endoscopic lens, and outcomes were assessed. A questionnaire regarding assistance, ergonomics, and instrument handling compared the Saraj Endocath procedure with the traditional technique.

RESULTS

The 3-hand technique was converted into the 2-hand technique. The mean operative time using the novel technique with the Saraj Endocath was reduced significantly compared with the traditional technique. The mean number of in-out movements of the endoscope and the number of wipes per hour decreased significantly using the Saraj Endocath. There was no dependency on the assistant's expertise and skills.

CONCLUSIONS

The use of the Saraj Endocath can effectively reduce the mean operative time by decreasing the frequency of in-out movement and wiping off the lens of the endoscope. It reduces fatigue, avoids clustering of instruments and hands, and minimizes the dependency on assistants.

One-and-a-half nostril versus binostril endoscopic transsphenoidal approach to the pituitary adenomas: A prospective randomized controlled trial

Background

Binostril endoscopic transsphenoidal approach (BETA) is the most used approach for sellar lesions nowadays, while its damage to the nasal structures may cause nasal discomfort and affect nasal functions including respiration and olfaction. With the purpose to improve the post-operative sinonasal quality of life (QoL), we introduced the one-and-a-half nostril endoscopic transsphenoidal approach (OETA) in 2016 which preserved more natural structures and registered a prospective randomized controlled trial (ChiCTR-IOR-16008222) to compare the two approaches regarding the surgical outcomes and complications.

Methods

Sixty patients with pituitary adenomas were recruited and randomly assigned to the OETA group and the BETA group between April 2016 and May 2017 in Jinling Hospital. The tumor resection rate, endocrinal and visual outcomes, and surgical complications between the OETA and BETA groups were analyzed. Besides, the questionnaire Anterior Skull Base Nasal Inventory-12 (ASK Nasal-12) was used to evaluate patients’ sinonasal QoL at seven time points (pre-operative; 2-weeks, 1-month, 3-months, 6-months, 12-months, and long-term post-operatively). The Sniffin’ Sticks were used to assess patients’ olfactory function objectively in a long term. Each patient was followed for at least 12 months post-operatively.

Results

There was no significant difference in tumor resection rate, hormonal and visual outcomes, and surgical complications between the two groups. Regarding the ASK Nasal-12, patients in the OETA group complained less about dried nasal material at 2 weeks after surgery (P = 0.017). One month after surgery, the OETA group had better olfaction function (P = 0.019) compared with the BETA group. However, there was no significant difference in early and long-term postoperative sinonasal QoL between the two approaches according to the entire ASK Nasal-12 metric. The results of the Sniffin’ Sticks showed that the two groups had a similar olfactory performance at long-time follow-up.

Conclusion

In this single tertiary center trial, the results showed that the OETA achieved the same surgical outcomes and post-operative sinonasal QoL as the BETA.

Clinical Trial Registration

http://www.chictr.org.cn/showproj.aspx?proj=13852, identifier: ChiCTR-IOR-16008222

Endoscopic technology and repair techniques

In this chapter, we describe advances in endoscopic endonasal surgery that have impacted skull base meningioma surgery. After reviewing the technical innovations in endoscopy, we describe the advances as they relate to each surgical step. We discuss preoperative planning and approach and the utility of neuronavigation and neuromonitoring. We then discuss endoscopic instrumentation, technology for tumor debulking (ultrasonic aspirators, radiofrequency ablators, suction debriders), and hemostatic agents as they relate to tumor resection and hemostasis. In the end, we discuss techniques of skull base reconstruction and closure (nasoseptal flap, gasket seal and bilayer button).

A case series and review of the mononostril endoscopic transnasal transsphenoidal approach: Safe and effective in a low resource setting

BACKGROUND

A transnasal transsphenoidal (TNTS) approach can be performed through a binostril or mononostril technique. The binostril technique is generally preferred, however the mononostril may be an underutilized approach with significant benefits.

METHODS

All (n = 521) pituitary adenoma transsphenoidal surgeries performed from March 2008 until July 2017 at a university hospital in Indonesia were isolated. The majority (n = 512) were performed through a mononostril approach with no nasal speculum by a single experienced neurosurgeon. A PubMed literature review researching the differences in indications, techniques, and outcomes for both approaches supplements the case series. The mononostril surgical technique is described in detail.

RESULTS

The average mononostril operating time was 105 min. The most prevalent surgical complications were CSF leak (4.1 %), diabetes insipidus (3.7 %) and cacosmia (2.1 %). Visual field deficits noted in 85 %, 89 % improved. Length of stay was less than 2 days for 90 %, with 13 ICU admissions (average one day). Recurrence rate was 8.2 % at follow up (1-10 years).

CONCLUSIONS

Based on a literature review, binostril TNTS surgeries have longer operative time and a higher risk of epistaxis. According to our experience, post-operative patient comfort and satisfaction are higher with the monostril approach. Furthermore, this technique is easier to teach, ENT assistance unnecessary, and thus especially advantageous in low resource settings. Our CSF leak and tumor recurrence rates were lower than reported binostril rates in the literature. The mononostril technique is both safe and effective and should be strongly considered for an appropriately pre-selected subset of pituitary adenomas.

The use of intraoperative computed tomography navigation in pituitary surgery promises a better intraoperative orientation in special cases

OBJECTIVE

The safety of endoscopic skull base surgery can be enhanced by accurate navigation in preoperative computed tomography (CT) and magnetic resonance imaging (MRI). Here, we report our initial experience of real-time intraoperative CT-guided navigation surgery for pituitary tumors in childhood.

MATERIALS AND METHODS

We report the case of a 15-year-old girl with a huge growth hormone-secreting pituitary adenoma with supra- and perisellar extension. Furthermore, the skull base was infiltrated. In this case, we performed an endonasal transsphenoidal approach for debulking the adenoma and for chiasma decompression. We used an MRI neuronavigation (Medtronic Stealth Air System) which was registered via intraoperative CT scan (Siemens CT Somatom). Preexisting MRI studies (navigation protocol) were fused with the intraoperative CT scans to enable three-dimensional navigation based on MR and CT imaging data. Intraoperatively, we did a further CT scan for resection control.

RESULTS

The intraoperative accuracy of the neuronavigation was excellent. There was an adjustment of <1 mm. The navigation was very helpful for orientation on the destroyed skull base in the sphenoid sinus. After opening the sellar region and tumor debulking, we did a CT scan for resection control because the extent of resection was not credible evaluable in this huge infiltrating adenoma. Thereby, we were able to demonstrate a sufficient decompression of the chiasma and complete resection of the medial part of the adenoma in the intraoperative CT images.

CONCLUSIONS

The use of intraoperative CT/MRI-guided neuronavigation for transsphenoidal surgery is a time-effective, safe, and technically beneficial technique for special cases.

The extended endoscopic approach to perisellar and skull base lesions: is one nostril enough?

The extended endonasal endoscopic approach to the skull base is still under investigation. The main advantage of using this technique is to approach lesions in a minimally invasive manner resulting without brain retraction. Here, the authors present the results of extended endonasal endoscopic surgery via one nostril. All skull base procedures performed via an endonasal approach at the author's Department between January 2011 and May 2017 were analysed prospectively. Special attention was paid to complications, radicality, advantages and disadvantages of the endoscopic technique. Additionally, the application of various telescopes and the technique of dural closure were analysed. Sixty-two patients were operated on various pathologies of the skull base via an extended endonasal approach. Seven pathologies were resected via binostril technique. All other pathologies could be exposed by the mononostril technique. In 2 of 62 cases, the authors had to switch to binostril technique. MRI revealed radical gross total resection in 93% of all cases when intended. Overall complication rate was 16% (9/55) in the mononostril and 57% (4/7) in the binostril cohort. Seven patients in the mononostril cohort (13%) versus three patients in the binostril cohort (43%) complained of postoperative nasal congestion. This clinical report shows that many extended skull base lesions can be treated by a mononostril endonasal approach. In selected cases, this technique might represent an alternative to the binostril approach. Nevertheless, the binostril technique offers a better range of manipulation and exposure and should be preferred in difficult and very extended cases.

Visualization and Identification of the Pituitary Gland Tissue in Endonasal Pituitary Surgery: Is There a Difference Between High-Definition Endoscopy and Microscopy?

OBJECTIVE

Neurosurgical techniques for the treatment of sellar pathologies have been evolving continuously over recent decades. In addition to the innovation of approaches and surgical techniques, this progress yielded to the application of modern operative technologies. The introduction of high-definition (HD) cameras for endoscopic systems has shown good results in endonasal pituitary surgery. The aim of this study was to assess endoscopic HD image quality in comparison with microscopic visualization.

METHODS

All pituitary surgeries were performed via an endonasal approach in the endoscopic technique. For each comparison, pituitary gland tissue was predefined intraoperatively. A resident was randomly required to identify this tissue either using HD endoscopic or microscopic visualization through the endonasal approach. Subjective image quality was requested with a questionnaire. Furthermore, the illuminance level of the endoscope and microscope was measured in the sellar region in an experimental setup.

RESULTS

Thirty-five procedures were performed and included in this comparison. Of the 35 procedures, 74% of gland tissue cases were identified correctly under endoscopic visualization, whereas it was identified correctly under microscopic visualization in 8% (P < 0.05). There was no significant correlation of experience and intraoperative results in cases of the microscopic (r = -0.15) or endoscopic visualization (r = 0.22). The identification of tissue in the depth of the surgical field via endoscopic HD visualization was thought to be superior to the microscope in 86.8%. Both modalities were assessed equal in 10.4%. Microscopic visualization was rated superior in 2.8% of all cases. There was a significant superiority of endoscopic visualization (P < 0.05). The mean lux level for endoscopic visualization of the sellar region was 221,000. The mean lux level decreased significantly by 66% to 241,000 lx with 350-mm distance and by 60% to 141,000 lx with 450-mm distance because of the positioning of the microscope in front of the head form to visualize the surgical field at the sellar region.

CONCLUSIONS

HD endoscopic visualization accounted for significantly more reliable identifications of pituitary gland tissue in comparison with the microscope in the presented setting. The subjective impression of image quality is better with HD endoscopes. The goal of further studies should be to identify if these findings would also result in improved surgical outcome in short-term and long-term follow-up.

Sinonasal outcome after endoscopic mononostril transsphenoidal surgery: A single center cohort study

OBJECTIVE

The endoscopic endonasal approach has been well established for skull base surgery. However, there are only few studies pointing out nasal complaints after surgery. In this study, the authors evaluated postoperative nasal complaints and complications after mononostril endoscopic procedures.

METHODS

All patients operated on parasellar and sellar pathologies at our department via an endoscopic mononostril transnasal transsphenoidal approach from January 2011 to May 2015 were analyzed. To assess specific postoperative nasal pathological conditions and complaints, a questionnaire was established. Applicable data of 79 patients with additional ENT follow-up could be included. Endpoints were the quantitative evaluation of complications and correlation of these data.

RESULTS

There was no vascular injury or worsening of visual function. Two patients had persisting CSF fistula and one of them meningitis. There was a significant decrease of nasal complaints during follow up after 2 years (p < 0.001). Further surgical treatment by ENT physician was necessary in 11.4%. Resurgery significantly increased the risk of postsurgical complaints (p < 0.005). The use of a tamponade significantly reduced the risk of postsurgical reduced nasal airflow (p = 0.026) and sinusitis (p = 0.002).

CONCLUSIONS

Endoscopic endonasal procedures to skull base lesions achieve high radicality with low complication rates. However, they induce temporary and permanent nasal complaints and complications. Thereby, resurgeries increase the risk of nasal complaints and the use of nasal tamponades might increase the sinonasal outcome. Further prospective studies are necessary to objectify the evaluation of postsurgical nasal complications.

The endoscopic surgical resection of intrasellar lesions conserves the hormonal function: a negative correlation to the microsurgical technique

BACKGROUND

The endonasal endoscopic approach is still currently under investigation for sellar tumor surgery: a higher resection rate is to be expected and complications should be minimized. The authors report their surgical results of endonasal endoscopic neurosurgery with special focus on postoperative hypopituitarism in comparison to microsurgical procedures.

METHODS

Sixty patients received endoscopic endonasal transsphenoidal procedures for sellar pathologies. All patients were followed up prospectively. A second group of 60 patients received microsurgical transsphenoidal procedures for sellar pathologies in our neurosurgical department before and were prospectively followed until now. Special attention was paid to hormonal insufficiency and medical substitution.

RESULTS

Sixty-eight percent (41 of 60) of the patients who underwent microsurgical procedures showed a new persisting pituitary insufficiency postoperatively. Twenty-three patients (55.5%) were substituted with thyroxine, hydrocortisone and sexual hormones and one patient (2.5%) also with ADH cause of global pituitary insufficiency. In 19 cases without any hormonal insufficiency after microsurgical procedures nine patients (47%) showed remnant tumor in follow-up MRI. The patients who underwent endoscopic procedures for pituitary adenomas revealed significant (P<0.01) less new persistent hormonal insufficiency with 13% of all cases (8/60). Five patients (62.5%) were substituted with thyroxine and hydrocortisone, two patients (25%) substituted with thyroxine, hydrocortisone and sexual hormones and one patient also with ADH because of global pituitary insufficiency. Thereby, in follow-up MRI and hormonal testing, radical tumor resection was detected in 92% in the endoscopic group.

CONCLUSIONS

This study seems to indicate that a better intraoperative identification and preservation of pituitary gland is possible in endoscopic transsphenoidal surgery with consecutive lower postoperative hypopituitarism rate.

Reaching the sellar region endonasally - One or both nostrils? A pilot study in body donors

INTRODUCTION

The purpose of this study was to evaluate the effect of posterior septectomy size on surgical exposure and surgical freedom during the endoscopic transsphenoidal approach to the sellar and parasellar region.

METHODS

A mononostril and binostril approach to the sellar region was performed on 4 formalin-fixed cadaveric heads. Predefined anatomical structures were identified. Additionally, a millimeter gauge was introduced into the surgical site and the extent of dorsal septectomy was analyzed for both approaches. Surgical freedom was defined as the distance between the ipsilateral and contralateral limit of opening of the sphenoid sinus.

RESULTS

The mean extent of dorsal septectomy was 15.7±5.7mm using a binostril approach to achieve adequate visualization of all relevant anatomical structures. Superior results were obtained via binostril technique with respect to the ability to identify the contralateral internal carotid artery or opticocarotid recessus. No such advantage was found for all other landmarks. Surgical freedom between the ipsilateral and contralateral limit of exposure of the sphenoid sinus was measured with 15±0.8mm in the mononostril and 19.2±0.9mm in the binostril group.

CONCLUSIONS

The surgical exposure increased significantly with progressively larger posterior septectomy in binostril approaches until a 20-mm posterior septectomy. Bilateral lateral opticocarotid recesses were accessible with a mean of 15mm for posterior septectomy. In the mononostril group no dorsal septectomy was necessary. Thus, the nasal mucosa is more preserved by this technique. However, the lateral exposure is partially limited and the use of angled endoscopes is recommended when adopting a mononostril approach to the sellar region.

Preservation of hormonal function by identifying pituitary gland at endoscopic surgery

OBJECTIVE

The endonasal endoscopic approach has been established for perisellar tumor surgery with a higher resection rate and reduced complications. We analyzed the potential to identify the pituitary gland under endoscopic view, at surgery and see its relation to postoperative hormonal insufficiency in endonasal endoscopic procedures.

METHODS

Between January 2011 and January 2014, 70 cases of pituitary adenomas with preoperative intact pituitary function underwent endoscopic endonasal transsphenoidal procedures for intrasellar pathologies. Endocrinologists and neurosurgeons followed these patients prospectively. Special attention was paid to intraoperative identification of gland tissue, surgical complications, degree of resection and postoperative hormonal insufficiency.

RESULTS

The pituitary gland was identified in 57 out of 70 procedures (81.4%). Eleven percent (8 of 70 patients) had persistent pituitary insufficiency. Two of these 8 patients belonged to the group with pituitary gland identification (2 out of 57); thus, when the pituitary gland was identified during the procedure postoperative hormonal insufficiency was seen in 3.5% of cases. Failure of pituitary gland identification presented with hormonal insufficiency of 46.2%. In analysis with Fisher's exact test, there was a high significant correlation between the identification of the pituitary gland intraoperatively and normal pituitary function postoperatively (p<0.005). On follow up radical tumor resection was seen in 88% (62 of 70 patients).

CONCLUSIONS

This study indicates that identification and preservation of pituitary gland tissue and function is possible in endoscopic transsphenoidal surgery. This preservation of gland tissue is a positive predictor of postoperative normal pituitary function.

Endoscopic Assisted Supraorbital Keyhole Approach or Endoscopic Endonasal Approach in Cases of Tuberculum Sellae Meningioma: Which Surgical Route Should Be Favored?

OBJECTIVE

Keyhole approaches are under investigation for skull base tumor surgery. They are expected to have a low complication rate with the same successful resection rate compared with endoscopic endonasal procedures. In this study, we compare our current series of tuberculum sellae meningiomas resected via an endoscopic endonasal or microsurgical supraorbital keyhole approach.

METHODS

Between 2011 and 2016, 16 patients were treated using the supraorbital keyhole procedure and 6 patients received an endoscopic endonasal procedure. Both surgical techniques were analyzed and compared concerning complications, surgical radicality, endocrinologic, and ophthalmologic outcome and recurrences in patients' follow-up.

RESULTS

The 2 different approaches yielded similar rates of gross total resection (endonasal 83% [5 of 6] vs. supraorbital 87% [14 of 16]), near total resection (17% [1 of 6] vs. 13% [2 of 16]), and visual recovery (endonasal 66% [2 of 3] vs. supraorbital 60% [3 of 5]). An extension lateral to the internal carotid artery was noted in 81% (13 of 16) of the supraorbital cases and in none of the endonasal cases. Tumor volume was 14.9 cm³ (±8.2 cm³) for supraorbital tumors versus 2.1 cm³ (±0.8 cm³) for the endonasal approach.

CONCLUSIONS

Both approaches provide minimally invasive surgical routes accessing meningiomas of the sellar region. The ideal approach should be tailored to the individual patient considering the tumor anatomy, lateral extension, and the experience of the surgeon with both surgical approaches. We suggest using the supraorbital approach for larger meningiomas of sellar region with far lateral extension or broad vascular encasement.

Binostril versus mononostril approaches in endoscopic transsphenoidal pituitary surgery: clinical evaluation and cadaver study

OBJECTIVE Over the past 2 decades, endoscopy has become an integral part of the surgical repertoire for skull base procedures. The present clinical evaluation and cadaver study compare binostril and mononostril endoscopic transnasal approaches and the surgical techniques involved. METHODS Forty patients with pituitary adenomas were treated with either binostril or mononostril endoscopic surgery. Neurosurgical, endocrinological, ophthalmological, and neuroradiological examinations were performed. Ten cadaver specimens were prepared, and surgical aspects of the preparation and neuroradiological examination were documented. RESULTS In the clinical evaluation, 0° optics were optimal in the nasal and sphenoidal phase of surgery for both techniques. For detection of tumor remnants, 30° optics were superior. The binostril approach was significantly more time consuming than the mononostril technique. The nasal retractor limited maneuverability of instruments during mononostril approaches in 5 of 20 patients. Endocrinological pituitary function, control of excessive hormone secretion, ophthalmological outcome, residual tumor, and rates of adverse events, such as CSF leaks and diabetes insipidus, were similar in both groups. In the cadaver study, there was no significant difference in the time required for dissection via the binostril or mononostril technique. The panoramic view was superior in the binostril group; this was due to the possibility of wider opening of the sella in the craniocaudal and horizontal directions, but the need for removal of more of the nasal septum was disadvantageous. CONCLUSIONS Because of maneuverability of instruments and a wider view in the sphenoid sinus, the binostril technique is superior for resection of large tumors with parasellar and suprasellar expansion and tumors requiring extended approaches. The mononostril technique is preferable for tumors with limited extension in the intra- and suprasellar area.

A practical 3D printed simulator for endoscopic endonasal transsphenoidal surgery to improve basic operational skills

PURPOSE

We aimed to present a practical three-dimensional (3D) printed simulator to comprehensively and effectively accelerate the learning curve of endoscopic endonasal transsphenoidal surgery (EETS).

METHODS

The 3D printed simulator consists of three parts: (1) skull frame, (2) the nasal passage and the nasal alar of the face, and (3) a modified sella turcica. We aimed to improve three basic operational skills of surgeons: drilling, curetting, and aspirating. Eighteen neurosurgeons and five post-graduates were recruited and consented for the training.

RESULTS

For trainees, (1) as the training progressed, the scores increased gradually, (2) a significant increase in the average scores was observed in the tenth training compared to the first training, and (3) there is a significant decrease in trainee variability in the shortening of the gap. The 18 neurosurgeons were divided into three groups: experts, assistants, and observers. For all three basic operations, (1) the average score of experts was obviously higher than that of the assistants, observers, and trainees' tenth training and (2) the average scores of assistants and observers were obviously higher than that of trainees' first training. A significant high in the average score between the assistants and the observers was seen for aspirating, but not for drilling or curetting. For curetting and aspirating, the tenth training average score of trainees was obviously higher than that of assistants and observers.

CONCLUSION

This 3D printed simulator allows different endoscopic basic operations to be simulated and improves the EETS techniques of surgeons. We believed it to be a practical, simple, and low-cost simulator.

Mononostril versus Binostril Endoscopic Transsphenoidal Approach for Pituitary Adenomas: A Systematic Review and Meta-Analysis

Background

Over the past several decades, the endoscopic endonasal transsphenoidal approach (EETA) has gradually become a preferred option of pituitary adenomas surgery because of its minimal invasiveness and high efficiency. However, some EETA operations were performed through one nostril (mononostril), while other EETA operations were performed through both nostrils (binostril). Therefore, we conducted this study to compare the pros and cons of these two methods in an attempted to confirm which method is more effective.

Methods

We executed a systematic literature search of PubMed, the Cochrane Library, and the Web of Science and Medline (1992–2015). The language is limited to English and all studies should meet the inclusion criteria. Comparisons were made for postoperative outcomes, complications, and other relevant parameters between the mononostril and the binostril group. Statistical analyses of categorical variables were undertaken by the use of Stata 12.0 and SPASS 19.0.

Results

Thirty studies, involving 4805 patients, were included. The two groups had similar results in GTR rate (included GTR rate of macroadenomas), hormonal remission rate, improvement in visual function, postoperative CSF leak, permanent diabetes insipidus, meningitis, and sinusitis. The binostril group had less temporary diabetes insipidus (2.9% vs. 5.3%, p = 0.022), less anterior pituitary insufficiency (2.3% vs. 6.4%, p = 0.000) and few hospitalization days (3.2 days vs. 4.4 days, p<0.05) than the mononostril group. However, the mononostril group had less rate of epistaxis (0.4% vs. 1.5%, p = 0.008) than the binostril group. For invasive macroadenomas, the binostril group seem to demonstrate a tendency towards better outcomes though there was no subgroup analysis between the two groups.

Conclusion

The binostril approach had less temporary diabetes insipidus, anterior pituitary insufficiency, and a shorter length of hospital stay, although they demonstrated a higher rate of epistaxis than the mononstril group. Additionally, the binostril group seemed to suggest a tendency towards better outcomes for invasive macroadenomas.

Endoscopic Modified Transseptal Transsphenoidal Approach for Maximal Preservation of Sinonasal Quality of Life and Olfaction

OBJECTIVE

Patients experience significant postoperative sinonasal symptoms for the first few months after endoscopic transnasal transsphenoidal approach (ETN-TSA) surgery. We modified this technique by bypassing the nasal mucosa and approaching through the septum bilaterally. In this study, we analyze whether these technical modifications, which we have termed the endoscopic modified transseptal transsphenoidal approach (EMTS-TSA), decrease postoperative sinonasal morbidity after endoscopic TSA.

METHODS

We retrospectively reviewed a prospectively collected database. Patients who underwent endoscopic TSA from December 2012 to June 2014 were included. Thirty patients underwent ETN-TSA, and 51 underwent EMTS-TSA. Sino-Nasal Outcome Test-20, anterior skull base nasal inventory, and visual analog scale (VAS) for subjective olfaction were evaluated before and 1 and 3 months after surgery. Cross Cultural Smell Identification Test also was measured before and 3 months after surgery.

RESULTS

There was a significant difference between the preoperative and 3-month VAS for olfaction in the ETN-TSA group (from 92.5 to 81.3; P = 0.002) but not the EMTS-TSA group (from 90.6 to 88.8; P = 0.403). There was no statistical difference in Sino-Nasal Outcome Test-20 or Cross-Cultural Smell Identification Test scores between 2 groups during follow-up. The EMTS-TSA group scored better than the ETN-TSA group in the anterior skull base nasal inventory subdomain ("nasal discharge," "urge to blow," and "trouble breading") 1 month postoperatively.

CONCLUSIONS

EMTS-TSA could preserve almost all nasal mucosa, including the septum and turbinates. EMTS-TSA may be useful for preserving early postoperative olfactory function and some sinonasal quality of life. We believe that EMTS-TSA is a good endoscopic pituitary surgery option.

Anatomic Study of Posterior Communicating Artery in Computed Tomographic Image

PURPOSE

This study aims to provide an anatomic data of posterior communicating artery (PComA) and its anatomic relationship to the adjacent structures, so as to guide surgeons in the surgery of internal carotid artery-posterior communicating artery aneurysm clipping and sellar tumors resection without injuring the PComA.

METHODS

Computer topographic angiography images of 123 individuals were reviewed, and the measurements were done on coronal, sagittal, axial, and other user-defined planes after multiplanar reconstruction. Posterior communicating artery was classified in the reconstructed three-dimensional image, measured in proper planes, and located by the structures such as anterior clinoid process (ACP), posterior clinoid process (PCP), and sagittal midline.

RESULTS

Six types of PComA were identified in this study based on its existence and origin. The initial part of PComA can be located by ACP, PCP, and sagittal midline based on some particular angles and distances.

CONCLUSIONS

Posterior communicating artery varies in different individuals, and the radiologic study of it is an optimal way to analyze the variances. The anatomic relations between PComA and basic skull structures such as the ACP and PCP are especially important for neurosurgeons.

Endoscopic Endonasal Transclival Resection of a Brainstem Cavernoma: A Detailed Account of Our Technique and Comparison with the Literature

OBJECTIVE

To report a technique of endoscopic transclival resection of a hemorrhagic brainstem cavernous malformation manifesting in the ventral pons.

METHODS

A 29-year-old woman presented with numbness and tingling of the right arm and leg and loss of fine motor control. Magnetic resonance imaging revealed a cavernoma in the ventromedial brainstem on the ventral surface. A purely endoscopic, endonasal, transclival approach was used to resect this cavernoma. Computed tomography/magnetic resonance imaging merged navigation (StealthStation, Medtronic) was used.

RESULTS

The patient had no neurologic deficits postoperatively. The motor control loss and tingling disappeared. She did not experience any complications. Cerebrospinal fluid leakage appeared to result from using the very small opening of the skull base and dura mater and was the reason for the use of a lumbar drain for several days. At the 6-week follow-up examination, the patient was in excellent condition with no neurologic deficits and had returned to her full-time job.

CONCLUSIONS

Successful endoscopic, endonasal, transclival resection of a brainstem cavernous malformation was described. This patient experienced improvement in neurologic symptoms after surgery without morbidity. Technologic advances in endoscopic skull base approaches provide access to lesions of the brainstem that previously required more invasive approaches. The endonasal transclival approach provides the most direct route to ventral pontine lesions. Early intervention in brainstem cavernous malformation is indicated and should be performed with an individualized approach taking into consideration the possible complications.