Diabetes Insipidus After Endoscopic Transsphenoidal Surgery.

BACKGROUND: Diabetes insipidus (DI) is a recognized transient or permanent complication following transsphenoidal surgery (TSS) for pituitary tumors. OBJECTIVE: To describe significant experience with the incidence of DI after TSS, identifying predictive characteristics and describing our diagnosis and management of postoperative DI. METHODS: A retrospective analysis was performed of 700 patients who underwent endoscopic TSS for resection of pituitary adenoma (PA), Rathke cleft cyst (RCC), or craniopharyngioma. Inclusion criteria included at least 1 wk of follow-up for diagnosis of postoperative DI. Permanent DI was defined as DI symptoms and/or need for desmopressin more than 1 yr postoperatively. All patients with at least 1 yr of follow-up (n = 345) were included in analyses of permanent DI. Multivariable logistic regression models were constructed to identify predictors of transient or permanent postoperative DI. RESULTS: The overall rate of any postoperative DI was 14.7% (103/700). Permanent DI developed in 4.6% (16/345). The median follow-up was 10.7 mo (range: 0.2-136.6). Compared to patients with PA, patients with RCC (odds ratio [OR] = 2.2, 95% CI: 1.2-3.9; P = .009) and craniopharyngioma (OR = 7.0, 95% CI: 2.9-16.9; P ≤ .001) were more likely to develop postoperative DI. Furthermore, patients with RCC (OR = 6.1, 95% CI: 1.8-20.6; P = .004) or craniopharyngioma (OR = 18.8, 95% CI: 4.9-72.6; P ≤ .001) were more likely to develop permanent DI compared to those with PA. CONCLUSION: Although transient DI is a relatively common complication of endoscopic and microscopic TSS, permanent DI is much less frequent. The underlying pathology is an important predictor of both occurrence and permanency of postoperative DI.

Prolactinomas and nonfunctioning adenomas: preoperative diagnosis of tumor type using serum prolactin and tumor size.

OBJECTIVE: Prolactinoma and nonfunctioning adenoma (NFA) are the most common sellar pathologies, and both can present with hyperprolactinemia. There are no definitive studies analyzing the relationship between the sizes of prolactinomas and NFAs and the serum prolactin level. Current guidelines for serum prolactin level cutoffs to distinguish between pathologies are suboptimal because they fail to consider the adenoma volume. In this study, the authors attempted to describe the relationship between serum prolactin level and prolactinoma volume. They also examined the predictive value that can be gained by considering tumor volume in differentiating prolactinoma from NFA and provide cutoff values based on a large sample of patients. METHODS: A retrospective analysis of consecutive patients with prolactinomas (n = 76) and NFAs (n = 217) was performed. Patients were divided into groups based on adenoma volume, and the two pathologies were compared. RESULTS: A strong correlation was found between prolactinoma volume and serum prolactin level (r = 0.831, p < 0.001). However, there was no significant correlation between NFA volume and serum prolactin level (r = -0.020, p = 0.773). Receiver operating characteristic curve analysis of three different adenoma volume groups was performed and resulted in different serum prolactin level cutoffs for each group. For group 1 (≤ 0.5 cm3), the most accurate cutoff was 43.65 µg/L (area under the curve [AUC] = 0.951); for group 2 (> 0.5 to 4 cm3), 60.05 µg/L (AUC = 0.949); and for group 3 (> 4 cm3), 248.15 µg/L (AUC = 1.0). CONCLUSIONS: Prolactinoma volume has a significant impact on serum prolactin level, whereas NFA volume does not. This finding indicates that the amount of prolactin-producing tissue is a more important factor regarding serum prolactin level than absolute adenoma volume. Hence, volume should be a determining factor to distinguish between prolactinoma and NFA prior to surgery. Current serum prolactin threshold level guidelines are suboptimal and cannot be generalized across all adenoma volumes.

Outcomes After Repeat Transsphenoidal Surgery for Recurrent Cushing Disease: Updated.

BACKGROUND: Transspheniodal surgery (TSS) for Cushing disease (CD) is considered the first-line treatment; however, reported recurrence rates are high. OBJECTIVE: To systemically review indications and outcomes for repeat TSS in recurrent CD. METHODS: Retrospective review of patients undergoing TSS from 2008 to 2018 was performed. Patients undergoing repeat TSS for clinical and/or biochemically recurrent CD with follow-up at least 12 mo postoperatively were included. These data were analyzed in our "current cohort" and combined with our previously published data in a "combined cohort." RESULTS: The current cohort of patients undergoing operations from 2008 to 2018 with repeat surgery following a prior operation included 15 patients. Pathology at the time of first operation was positive for adrenocortiotrophic hormone (ACTH) adenoma in 13/15 (86.7%) and 9/15 (60%) had evidence of recurrence after a previous surgical procedure on preoperative magnetic resonance imaging (MRI). Remission was achieved immediately postoperatively in 13/15 (86.7%). Over an average follow-up of 34.7 mo (range: 12-116), 11/15 (68.8%) achieved persistent remission. When combined with the historical cohort that underwent an operation during 1992-2006, 44/51 (86.3%) patients had a prior operation demonstrating ACTH adenoma and 35/51 (68.6%) had evidence of recurrent disease on preoperative MRI. Thirty-five (68.6%) patients went into remission immediately postoperatively. Thirty one (60.8%) had continued remission at most recent reported follow-up. CONCLUSION: Recurrent CD can be a therapeutic challenge; however, these data demonstrate that in many patients repeat surgery can be an effective and safe next step prior to radiation or medical therapy.

Abdominal Fat Graft for Sellar Reconstruction: Retrospective Outcomes Review and Technical Note.

BACKGROUND: The transsphenoidal approach is the standard of care for the treatment of pituitary adenomas and is increasingly employed for many anterior skull base tumors. Persistent postoperative cerebrospinal fluid (CSF) leaks can result in significant complications. OBJECTIVE: To analyze our series of patients undergoing abdominal fat graft repair of the sellar floor defect following transsphenoidal surgery, describe and investigate our current, routine technique, and review contemporary and past methods of skull base repair. METHODS: A recent consecutive series (2008-2017) of 865 patients who underwent 948 endonasal procedures for lesions of the sella and anterior skull base was retrospectively reviewed. Three hundred eighty patients underwent reconstruction of the sellar defect with an abdominal fat graft. RESULTS: The diagnoses of the 380 patients receiving fat grafts were the following: 275 pituitary adenomas (72.4%), 50 Rathke cleft cysts (13.2%), 12 craniopharyngiomas (3.2%), and a variety of other sellar lesions. Fourteen patients had persistent postoperative CSF leak requiring reoperation and included: 5 pituitary adenomas (1.3%), 4 craniopharyngiomas (1.1%), 2 arachnoid cysts (0.53%), 2 prior CSF leaks (0.53%), and 1 Rathke cleft cyst (0.26%). Four patients (1.1%) developed minor abdominal donor site complications requiring reoperation: 1 hematoma, 2 wound complications, and 1 keloid formation resulting in secondary periumbilical infection. CONCLUSION: Minimizing postoperative CSF leaks following endonasal anterior skull base surgery is important to decrease morbidity and to avoid a prolonged hospital stay. We present an evolved technique of abdominal fat grafting that is effective and safe and includes minimal morbidity and expense.

Acute Heart Failure at the Time of Transcatheter Aortic Valve Replacement Does Not Increase Mortality.

OBJECTIVE: Patients presenting for transcatheter aortic valve replacement are often in acute on chronic heart failure, as indicated by elevated N-terminal pro-B-type natriuretic peptide. Many believe that elevated N-terminal pro-B-type natriuretic peptide is an indication to treat medically, reserving surgery until the patient is medically optimized. METHODS: A single-center transcatheter aortic valve replacement database was queried from December 2015 to November 2016 to identify patients undergoing transcatheter aortic valve replacement. Patients were divided into two cohorts based on preoperative N-terminal pro-B-type natriuretic peptide level. An analysis was then completed to assess outcomes such as length of intensive care unit stay, total length of stay, discharge to home, major complications, and mortality at 30 days. RESULTS: There were 142 patients (median age = 80 years, 44% female) with preoperative N-terminal pro-B-type natriuretic peptide data included (range = 106-73,500 pg/mL). The mean Society of Thoracic Surgeons predicative risk of mortality was 8%, and 46 patients (32%) had N-terminal pro-B-type natriuretic peptide of greater than 3000 pg/mL. N-terminal pro-B-type natriuretic peptide of greater than 3000 pg/mL was associated only with increased intensive care unit length of stay of greater than 24 hours (35% vs 9%, P = 0.0001). There was no statistical difference between cohorts with regard to total length of stay of greater than 3 days (24% vs 15%, P = 0.2), discharge to home (74% vs 83%, P = 0.3), major complication, or mortality at 30 days. CONCLUSIONS: Transcatheter aortic valve replacement is an appropriate and effective treatment for patients with aortic stenosis presenting with high N-terminal pro-B-type natriuretic peptide and acute on chronic heart failure.

Management of non-functioning pituitary adenomas: surgery.

Non-functional pituitary adenomas (NFPAs) are benign tumors of the pituitary gland that do not over-secrete hormonal products, therefore, they are generally detected through symptoms of mass effect, including headache, vision loss, or hypopituitarism. There are multiple pathological subtypes of NFPAs, such as null cell adenomas, silent gonadotrophs, silent somatotrophs, silent corticotrophs, and silent subtype 3, all of which can be classified based on immunohistochemical studies and electron microscopy. Despite these numerous pathological subtypes, surgical resection remains the first-line treatment for NFPAs. Diagnosis is best made using high resolution MRI brain with and without gadolinium contrast, which is also helpful in determining the extent of invasion of the tumor and recognizing necessary sinonasal anatomy prior to surgery. Additional pre-operative work-up should include full laboratory endocrine evaluation with replacement of hormone deficiencies, and ideally, full neuro-ophthalmologic exam. Although transcranial surgical approaches to the pituitary gland can be performed, the most common approach used is the transnasal transsphenoidal approach with endoscopic or microscopic visualization. This approach avoids retraction of the brain and cranial nerves during tumor removal. Surgery for symptoms caused by mass effect, including headaches and visual loss, are successfully treated with surgical resection, resulting in improvement in pre-operative symptoms as high as 90% in some reports. Although the risk of complications is low, major and minor events, such as permanent hypopituitarism, persistent CSF leak, and carotid artery injury can occur at rates ranging from zero to about 9%.

A practical method for prevention of readmission for symptomatic hyponatremia following transsphenoidal surgery.

INTRODUCTION: Patients undergoing transsphenoidal pituitary surgery (TSS) are at risk for several serious complications, including the syndrome of inappropriate antidiuretic hormone and subsequent hyponatremia. OBJECTIVE: In this study, we examined the effect of 1 week of post-discharge fluid restriction to 1.0 L daily on rates of post-operative readmission for hyponatremia. METHODS: We retrospectively analyzed all patients undergoing TSS from 2008 to 2014 and prospectively recorded patient data from 2015 to 2017. Patients were divided into a control cohort (2008-2014), who were discharged with instructions to drink to thirst; and an intervention cohort (2015-2017) who were instructed to drink less than 1.0 L daily for 1 week post-operatively. RESULTS: This study included 788 patients; 585 (74.2%) in the control cohort and 203 (25.8%) in the intervention cohort. Overall, 436 (55.3%) were women, the median age was 47 (range 15-89), and average BMI was 29.4 kg/m2 (range 17.7-101.7). Patients were relatively well matched. Of patients in the intervention group, none was readmitted for hyponatremia (0/203), compared to 3.41% (20/585) in the control group (p = 0.003). Patients in the intervention group also had significantly higher post-operative week one sodium levels (140.1 vs 137.5 mEq/L; p = 0.002). No fluid balance complications occurred in patients who followed this protocol. CONCLUSION: Hyponatremia can be a life-threatening complication of TSS, and prevention of readmission for hyponatremia can help improve patient safety and decrease costs. Mandatory post-discharge fluid restriction is a simple and inexpensive intervention associated with decreased rates of readmission for hyponatremia and normal post-operative sodium levels.

Safety of remifentanil in transsphenoidal surgery: A single-center analysis of 540 patients.

Although some studies have examined the efficacy and safety of remifentanil in patients undergoing neurosurgical procedures, none has examined its safety in transsphenoidal operations specifically. In this study, all transsphenoidal operations performed by a single author from 2008 to 2015 were retrospectively reviewed to evaluate the safety of remifentanil in a consecutive series of patients. During the study period, 540 transsphenoidal operations were identified. Of these, 443 (82.0%) patients received remifentanil intra-operatively; 97 (18.0%) did not. The two groups were well-matched with regard to demographic categories, comorbidities, and pre-operative medications (p>0.05), except pre-operative tobacco use (p=0.021). Patients were also well-matched with regard to radiographic features and surgical techniques. Patients who received remifentanil were more likely to harbor a macroadenoma (78.1% vs. 67.0%, p=0.025), and had slightly longer anesthesia time on average (269.2minvs. 239.4min, p=0.024). All pathologic diagnoses were well-matched between the two groups, except that patients receiving remifentanil were more likely to harbor a non-functioning adenoma (46.5% vs. 26.8%, p<0.001). Analysis of post-operative complications showed no significant difference between patients who received remifentanil and those who did not, and length of stay and prevalence of ICU stay did not differ between the two groups. In a well-matched series of 540 patients undergoing transsphenoidal surgery, remifentanil was found to be a safe anesthetic adjunct. There were no significant differences in post-operative hospital course or complications in patients who did and did not receive intra-operative remifentanil.

Time Course of Resolution of Hyperprolactinemia After Transsphenoidal Surgery Among Patients Presenting with Pituitary Stalk Compression.

BACKGROUND: Primary lactotroph disinhibition, or stalk effect, occurs when mechanical compression of the pituitary stalk disrupts the tonic inhibition by dopamine released by the hypothalamus. The resolution of pituitary stalk effect-related hyperprolactinemia postoperatively has not been studied in a large cohort of patients. We performed a retrospective review to investigate the time course of recovery of lactotroph disinhibition after transsphenoidal surgery. METHODS: Medical records were retrospectively reviewed for all patients undergoing transsphenoidal surgery with the senior author from April 2008 to November 2014. RESULTS: Of 556 pituitary adenomas, 289 (52.0%) were eliminated: 77 (13.9%) had an immunohistochemically confirmed prolactinoma, 119 (21.4%) patients had previous surgery, 93 (16.7%) had incomplete medical records, leaving 267 patients (48.0%) for final analysis. Of these patients, 72 (27.0%) had increased serum prolactin levels (≥23.3 ng/mL), suggestive of pituitary stalk effect (maximum prolactin level = 148.0 ng/mL). Patients with stalk effect were more likely than those with normal serum prolactin levels to present with menstrual dysfunction (29.7% vs. 19.4%; P < 0.01) and galactorrhea (11.1% vs. 2.1%; P < 0.01). Patients with lactotroph disinhibition were more likely to harbor macroadenomas than were patients who did not show lactotroph disinhibition (81.9% vs. 70.2%; P = 0.06). Among patients with increased preoperative prolactin, 77.8% experienced normalization of serum prolactin postoperatively, galactorrhea improved in 100%, sexual dysfunction resolved in 66.6%, and menstrual dysfunction among premenopausal females normalized in 73.3% at last follow-up (mean, 5.35 years; range, 0.1-10 years). CONCLUSIONS: Transsphenoidal surgery can provide durable normalization of serum prolactin levels and related symptoms caused by pituitary stalk compression-related lactotroph disinhibition.

Time Course of Symptomatic Recovery After Endoscopic Transsphenoidal Surgery for Pituitary Adenoma Apoplexy in the Modern Era.

BACKGROUND: Pituitary tumor apoplexy can result from either hemorrhagic or infarctive expansion of pituitary adenomas, and the related mass effect can result in compression of critical neurovascular structures. The time course of recovery of visual field deficits, headaches, ophthalmoparesis, and pituitary dysfunction after endoscopic transsphenoidal surgery has not been well established. METHODS: Medical records were retrospectively reviewed for all patients who underwent endoscopic transsphenoidal surgery for pituitary tumor apoplexy from April 2008 to November 2014. RESULTS: Of 578 patients who underwent transsphenoidal surgery, pituitary tumor apoplexy was identified in 44 patients (7.6%). Two patients had prior surgery, leaving 42 patients for final analysis. These included infarction-related apoplexy in 7 (14.4%) patients, and hemorrhagic apoplexy in 35 (85.6%) patients. Hemorrhagic adenomas had a larger axial tumor diameter than patients with infarctive adenomas (4.4 ± 4.1 cm vs. 1.8 ± 0.8 cm; P < 0.01), but were otherwise equivalent. At an average last follow-up of 2.52 years (range, 0.1-6.7 years), resolution of ophthalmoparesis as a result of pituitary tumor apoplexy demonstrated the longest recovery course (range, 2.4 ± 2.2 months) compared with visual field deficits (range, 8.0 ± 9.9 days), headaches (range, 1.9 ± 3.0 days), or pituitary dysfunction (range, 2.0 ± 1.8 weeks; P < 0.01). All patients who presented with headaches (n = 37) and/or visual disturbances (n = 22) had complete resolution of symptoms at last follow-up, whereas 83.3% of patients who presented with ophthalmoplegia experienced resolution. Endocrinologic dysfunction remained relatively consistent after surgery. CONCLUSIONS: Endoscopic transsphenoidal surgery can provide durable resolution of symptoms for patients presenting with pituitary tumor apoplexy. Recovery from headaches, visual, and pituitary dysfunction may be more rapid compared with ophthalmoparesis.

Risk factors for post-operative respiratory failure among 94,621 neurosurgical patients from 2006 to 2013: a NSQIP analysis.

INTRODUCTION: Post-operative respiratory failure can occur after neurosurgical operations. Identification of risk factors for respiratory failure after neurosurgery may help guide clinical decision-making, decrease length of stay, improve patient outcomes, and lower costs. METHODS: We performed a search of the ACS-NSQIP database for all patients undergoing operations with a neurosurgeon from 2006 to 2013. We analyzed demographics, past medical history, and post-operative respiratory failure, defined as unplanned intubation and/or ventilator dependence for more than 48 h post-operatively. RESULTS: Of 94,621 NSQIP-reported neurosurgical patients from 2006 to 2013, 2325 (2.5 %) developed post-operative respiratory failure. Of these patients, 1270 (54.6 %) were male, with an overall mean age of 60.59 years; 571 (24.56 %) were current smokers and 756 (32.52 %) were ventilator-dependent. Past medical history included dyspnea in 204 patients (8.8 %), COPD in 198 (8.5 %), and congestive heart failure in 66 (2.8 %). The rate of post-operative respiratory failure decreased from 4.1 % in 2006 to 2.1 % in 2013 (p < 0.001). Of the 2325 patients with respiratory failure, 1061 (45.6 %) underwent unplanned intubation post-operatively and 1900 (81.7 %) were ventilator-dependent for more than 48 h. The rate of both unplanned intubation (p < 0.001) and ventilator dependence (p < 0.001) decreased significantly from 2006 to 2013. Multivariate analysis demonstrated that significant risk factors for respiratory failure included inpatient status (p < 0.001, OR = 0.165), age (p < 0.001, OR = 1.014), diabetes (p = 0.001, OR = 1.489), functional dependence prior to surgery (p < 0.001, OR = 2.081), ventilator dependence (p < 0.001, OR = 10.304), hypertension requiring medication (p = 0.005, OR = 1.287), impaired sensorium (p < 0.001, OR = 2.054), CVA/stroke with or without neurological deficit (p < 0.001, OR = 2.662; p = 0.002, OR = 1.816), systemic sepsis (p < 0.001, OR = 1.916), prior operation within 30 days (p = 0.026, OR = 1.439), and operation type (cranial relative to spine, p < 0.001, OR = 4.344, Table 4). CONCLUSIONS: Based on the NSQIP database, risk factors for respiratory failure after neurosurgery include pre-operative ventilator dependence, alcohol use, functional dependence prior to surgery, stroke, and recent operation. The overall rate of respiratory failure decreased from 4.1 % in 2006 to 2.1 % in 2013 according to these data.

United States neurosurgery annual case type and complication trends between 2006 and 2013: An American College of Surgeons National Surgical Quality Improvement Program analysis.

We aimed to identify trends in the neurosurgical practice environment in the United States from 2006 to 2013 using the American College of Surgeons-National Surgical Quality Improvement Program (NSQIP) database, and to determine the complication rate for spinal and cranial procedures and identify risk factors for post-operative complications across this time period. We performed a search of the American College of Surgeons-NSQIP database for all patients undergoing an operation with a surgeon whose primary specialty was neurological surgery from 2006 to 2013. Analysis of patient demographics and pre-operative co-morbidities was performed, and multivariate analysis was used to determine predictors of surgical complications. From 2006 to 2013, the percentage of spinal operations performed by neurosurgeons relative to cranial and peripheral nerve cases increased from 68.0% to 76.8% (p<0.001) according to the NSQIP database. The proportion of cranial cases during the same time period decreased from 29.7% to 21.6% (p<0.001). The overall 30-day complication rate among all 94,621 NSQIP reported patients undergoing operations with a neurosurgeon over this time period was 8.2% (5.6% for spinal operations, 16.1% for cranial operations). The overall rate decreased from 11.0% in 2006 to 7.5% in 2013 (p<0.001). Several predictors of post-operative complication were identified on multivariate analysis.