Safety and efficacy of the direct endonasal transsphenoidal approach for challenging sellar tumors

Territorial and Extraterritorial Trigeminocardiac Reflex: A Review for the Neurosurgeon and a Type IV Reflex Vignette

The trigeminocardiac reflex (TCR) is a complex and, sometimes, fatal event triggered by overstimulation of the trigeminal nerve (TN) and its territorial and spinal cord branches. We reviewed and compiled for the neurosurgeon key aspects of the TCR that include a novel and straightforward classification, as well as morphophysiology, pathophysiology, neuromonitoring and neuromodulation features. Further, we present intraoperative data from a patient who developed extraterritorial, or type IV, TCR while undergoing a cervical surgery. TCR complexity, severity and unwanted outcomes indicate that this event should not be underestimated or overlooked in the surgical room. Timely TCR recognition in surgical settings is valuable for applying effective intraoperative management to prevent catastrophic outcomes.

Management of Giant Pituitary Adenomas: Role and Outcome of the Endoscopic Endonasal Surgical Approach

Giant adenomas represent a significant surgical challenge. Although traditionally several transcranial and transsphenoidal microscopic approaches have had a central role in their management, in the last 2 decades here have been increasing reports of the endoscopic endonasal approach for giant adenomas, citing its improved resection rates and lower complication profile. However, its role as the preferred approach has not been fully established and there is currently a paucity of evidence-based recommendations available in the literature. This article reviews the current literature and attempts to define the role and outcomes of the endoscopic endonasal surgical approach for giant pituitary adenomas.

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.

How to deal with giant pituitary adenomas: transsphenoidal or transcranial, simultaneous or two-staged?

Giant pituitary adenomas (diameter >4 cm) are a challenge to treat, and there is no consensus on the optimal surgical strategy. We report here our experience in surgical management of these lesions. Adult patients with giant pituitary adenomas (n = 62; 54 non-functioning and eight hormone-secreting adenomas) who underwent surgical resection at our hospital from 2009 to 2015 were retrospectively reviewed. Surgical and clinical outcomes were analyzed. Single transsphenoidal and transcranial approaches were used in 43 (69.4%) and four (6.5%) patients, respectively. A combined transsphenoidal and transcranial approach was used in 13 patients (20.9%) and in two patients (3.2%), a transcranial procedure was followed 3 months later by a transsphenoidal approach. Greater than 90% resection was achieved in 47 cases (75.8%). During a mean follow-up period of 46.9 months, 49 patients (79%) showed improved visual impairment scores, while none experienced visual deterioration. There was no post-operative hemorrhage or mortality. A total of 27 patients (43.5%) received adjuvant medical and/or radiation therapy. At last follow-up, eight patients (12.9%) had recurrence. For giant pituitary adenoma, the transsphenoidal and transcranial approaches should be combined flexibly based on the characteristics of the tumor. In certain cases, a simultaneous combined approach can maximize tumor extirpation and lower the risk of swelling and bleeding of the residual tumor.

Use of Tissue Glues in Endoscopic Pituitary Surgery: A Cost Comparison

Background:

Post-operative cerebrospinal fluid (CSF) leaks are a common complication of endoscopic pituitary surgery and account for a significant proportion of hospital costs associated with this procedure. Tisseel® is a tissue glue commonly used as an adjunct in dural repair but is not optimal for this purpose. DuraSeal® has several properties advantageous for dural repair but is not widely accepted in Canada partly due to its increased cost.

Objective:

A cost analysis of DuraSeal® versus Tisseel® in endoscopic pituitary surgery.

Methods:

A cost analysis was performed based on typical endoscopic pituitary surgery cases performed at our tertiary care institution. Operating room, hospital admission, and surgical sealant costs were obtained directly while estimates of patient recovery time and post-operative CSF leak rates were based on consensus values reported in the literature. Outcomes were reported for various possible clinical scenarios of sealant use.

Results:

In a model where surgical sealant is employed only in high-risk cases, use of DuraSeal® allows for a yearly cost savings of at least $4486.72. If surgical sealant is used in all cases, regular use of DuraSeal® versus Tisseel® either marginally reduces yearly costs or increases them by a maximum of $7619.25, depending on the case volume and estimated post-operative CSF leak rate.

Conclusion:

In most clinical scenarios, use of DuraSeal® in endoscopic pituitary surgery may reduce overall yearly hospital costs compared to Tisseel®.

Severe hyperthermia, hypernatremia, and early postoperative death after transethmoidal cavitron ultrasonic surgical aspirator (CUSA)-assisted diencephalic mass removal in 4 dogs and 2 cats

OBJECTIVE

To report clinical findings including severe hyperthermia and hypernatremia after transethmoidal Cavitron ultrasonic surgical aspirator (CUSA)-assisted diencephalic mass removal.

STUDY DESIGN

Retrospective case series.

ANIMALS

Dogs (n = 4) and 2 cats.

METHODS

Medical records (1997-2003) of dogs and cats that had transethmoidal CUSA-assisted diencephalic mass removal were reviewed. Retrieved data were: history, signalment, blood work, neurologic examination findings, MRI results, histopathology, postoperative complications, pre- and postoperative medical therapy, and outcome.

RESULTS

Tumor types included: meningioma (n = 3), choroid plexus papilloma (1), astrocytoma (1), and pituitary macroadenoma (1). Median onset of hyperthermia was 3.5 hours (range: 1-6 hours) after extubation; median high temperature at onset was 40.3°C, (range: 39.6-41.7°C). Median onset of hypernatremia (median, 172 mmol/L; range: 168-196 mmol/L) was 4.5 hours (range: 1-9 hours) after extubation. Median time of death after hyperthermia was 10.5 hours (range: 6-13 hours) and after extubation was 13.5 hours (range: 11-15 hours).

CONCLUSIONS

Transethmoidal CUSA-assisted diencephalic mass removal is associated with early postoperative hyperthermia, hypernatremia, and death, and cannot be recommended.

Surgical approaches to central skull base and postsurgical imaging

The close proximity to or intricate involvement of critical neurovascular structures in the central skull base region or both present unique surgical challenges. Varied surgical approaches may be used to remove tumors in this region, including open craniotomies and minimally invasive transnasal or transfacial endoscopic approaches. The ideal surgical technique is chosen based on multiple factors including the aggressiveness, histopathology, and location of the tumor with respect to regional neurovascular elements. Postsurgical image analysis of the central skull base requires an intimate understanding of preoperative and expected postoperative appearance in relation to the nature of the excision and surgical materials used.

Frontobasal interhemispheric approach for large superasellar craniopharyngiomas: do the benefits outweigh the risks?

OBJECTIVE

Large suprasellar craniopharyngiomas are surgically challenging. The aim of our study was to explore the therapeutic efficacy of the frontobasal interhemispheric approach for these lesions.

METHODS

Twenty-nine consecutive adult patients with large suprasellar craniopharyngiomas (diameter >4 cm) who underwent the frontobasal interhemispheric approach were retrospectively evaluated. Surgical and clinical outcomes were analyzed.

RESULTS

Gross total removal was achieved in 23 cases (79.3%) and subtotal removal in 6 cases (20.7%). The mean follow-up period was 76.5 ± 33.2 months (range, 12-132 months). Twenty-four patients (82.7%) had improvement of the visual impairment score (VIS) after surgery. VIS was unchanged in five patients (17.3%), and no patients experienced visual deterioration. Among 23 patients who had preoperative hypopituitarism, 8 (34.8%) had an improvement. Postoperative new or aggravated hypopituitarism was observed in four patients (13.8%). Permanent diabetes insipidus was observed in ten patients (34.4%). Postoperative anosmia occurred in two earlier cases (6.9%). There was no intracranial infection or cerebrospinal fluid fistula. At last follow-up, >9% BMI gain was observed in 34.5% of patients, and 65.5% of patients returned to work. Four patients (13.8%) suffered recurrence.

CONCLUSION

Although the frontobasal interhemispheric approach has some disadvantages, it provides ideal access to the suprasellar region and the third ventricle with limited brain retraction. The surgically visible angle is adequate; thus, vital structures can be better protected. For large suprasellar craniopharyngiomas, the benefits of this approach can outweigh its potential risks.

Barrier-limited multimodality closure for reconstruction of wide sellar openings

BACKGROUND

Obtaining a watertight reconstruction with a fat graft with wide sellar exposures can be challenging, including the risk of reinstating mass effect with the fat graft. The alternative, a vascularized pedicle nasoseptal flap, may require several days to heal and still has a > 5% cerebrospinal fluid (CSF) leak rate.

OBJECTIVE

To assess the efficacy of a barrier-limited multimodality (BLMM) closure, consisting of an autograft fat-based watertight seal and limited by a membrane barrier, together with the vascularized nasoseptal flap.

METHODS

This is a retrospective review of 27 consecutive patients undergoing endonasal cranial base surgery limited to the sellar-parasellar region at the UCLA Medical Center who experienced an intraoperative CSF leak that was repaired with the BLMM technique. The results of 43 prior case-controlled reconstructions using a nasoseptal flap, without the full BLMM technique, were analyzed as a comparison group.

RESULTS

There were no postoperative CSF leaks in the patients reconstructed with the BLMM closure technique. The CSF leak rate for the comparison group receiving nasoseptal flaps was 19%.

CONCLUSION

A BLMM closure may further decrease the incidence of postoperative CSF leaks compared with predominant reliance on a nasoseptal flap. The novel membrane barrier allows a watertight inner closure by preventing herniation of the fat autograft into the resection cavity. An outer-layer nasoseptal flap provides a living barrier for optimal long-term defense.

An endoscopic modification of the simultaneous 'above and below' approach to large pituitary adenomas

Surgical resections of large-to-giant pituitary adenomas (PA) are technically challenging procedures. Tumors with a fibrous consistency or 'hour-glass' configurations are particularly difficult to remove completely and safely through the transsphenoidal route alone. Although the transcranial approach can facilitate the removal of a large suprasellar mass, it may be associated with significant bleeding within the intradural space. A simultaneous microscopic transcranial and transsphenoidal approach has been described as an alternative surgical strategy. We have further modified this 'above and below' approach by adopting endoscopic techniques for the transsphenoidal part of the procedure. This modified approach has the advantages of requiring only one operating microscope, and permitting freer maneuvers and easier orientation for both surgical teams. We present two patients successfully treated with this approach. Complete tumor removal was achieved and both patients achieved satisfactory functional recovery.

Rathke cleft cysts in pediatric patients: presentation, surgical management, and postoperative outcomes

OBJECT

Rathke cleft cysts (RCC) are benign sellar lesions most often found in adults, and more infrequently in children. They are generally asymptomatic but sometimes require surgical treatment through a transsphenoidal corridor. The purpose of this study was to compare adult versus pediatric cases of RCC.

METHODS

The authors retrospectively reviewed presenting symptoms, MR imaging findings, laboratory study results, and pathological findings in 147 adult and 14 pediatric patients who underwent surgery for treatment of RCCs at the University of Californial at San Francisco between 1996 and 2008.

RESULTS

In both the adult and pediatric groups, most patients were female (78% of adults, 79% of pediatric patients, p = 0.9). Headache was the most common symptom in both groups (reported by 50% of pediatric patients and 33% of adults, p = 0.2). Preoperative hypopituitarism occurred in 41% of adults and 45% of pediatric patients (p = 0.8). Growth delay, a uniquely pediatric finding, was a presenting sign in 29% of pediatric patients. Visual complaints were a presenting symptom in 16% of adult and 7% of pediatric patients (p = 0.4). There was no difference between median cyst size in adults versus pediatric patients (1.2 cm in both, p = 0.7). Temporary or permanent postoperative diabetes insipidus occurred in 12% of adults and 21% of pediatric patients (p = 0.4). Kaplan-Meier analysis revealed an 8% RCC recurrence rate at 2 years for each group (p = 0.5).

CONCLUSIONS

The incidence of RCCs is much lower in the pediatric population; however, symptoms, imaging findings, and outcomes are similar, suggesting that pediatric RCCs arise from growth of remnants of the embryonic Rathke pouch earlier in life than adult RCCs but do not differ in any other way. It is important to consider RCCs in the differential diagnosis when pediatric patients present with visual impairment, unexplained headache, or hypopituitarism including growth delay. Although the average RCC size was similar in our pediatric and adult patient groups, the smaller size of the pituitary gland in pediatric patients suggests an increased relative RCC size.

Combined simultaneous transcranial and transsphenoidal resection of large-to-giant pituitary adenomas

Background

While large-to-giant pituitary adenomas (PAs) may be safely removed by experienced surgeons through a single route, the procedure is technically challenging. We present the outcome of a simultaneous combined transcranial and transsphenoidal approach and discuss its applications.

Methods

A retrospective review was conducted on 12 consecutive patients. Surgical complications, visual and endocrinological functions, and tumour control were reviewed.

Results

There were four men and eight women, with a mean age of 47.6 years. All but one patient had non-functioning PAs. The mean tumour height was 4.1 cm (range: 2.3–5.5). The predominant presenting symptoms were visual field loss in eight patients, headache in three patients and mental confusion in one patient. There was no operative mortality. Post-operative cerebrospinal fluid leakage occurred in one patient. Five of the eight patients who presented with visual field loss achieved full recovery, and three had partial improvement. Two patients developed permanent diabetes insipidus after surgery. Panhypopituitarism occurred in one patient. Gross total removal (GTR) was achieved in five, and subtotal removal (STR) in seven patients. Seven patients received post-operative external irradiation. All patients who had GTR remained tumour-free and all those with STR had stable diseases after a mean follow-up period of 53.1 months (range: 14.1–92.1).

Conclusion

The simultaneous ‘above and below’ approach is a safe and effective surgical strategy for large-to-giant PAs, particularly when expertise in endoscopic transsphenoidal surgery is unavailable. Its use, however, should be limited to a carefully selected group of patients, and tailored to individual user’s expertise and experience.

A technical note on endonasal combined microscopic endoscopic with free head navigation technique of removal of pituitary adenomas

Pituitary surgery exemplifies the continuous refinement of surgical techniques. The transsphenoidal approach is the approach of choice to treat most pituitary adenomas. We report here, as a technical note, an operative nuance that represents an encompassment of various technical steps that we utilize in our current surgery, including the corroboration of navigation system on a free head with combined use of endoscope and microscope techniques.