Kunal S. Patel

Case-specific protocol to reduce cerebrospinal fluid leakage after endonasal endoscopic surgery

OBJECTnEndoscopic transsphenoidal surgery is expanding in acceptance, yet postoperative CSF leak rates remain a concern. This study presents the Cornell closure protocol, which has yielded significantly lower postoperative CSF leak rates compared with prior reports, as an algorithm that can be used by centers having difficulty with CSF leak.nnnMETHODSnA single closure algorithm for endoscopic surgery has been used since January 2010 at Weill Cornell Medical College. A prospective database noting intraoperative CSF leak, closure technique, and postoperative CSF leak was reviewed. The authors used a MEDLINE search to identify similar studies and compared CSF leak rates to those of patients treated using the Cornell algorithm.nnnRESULTSnThe retrospective study of a prospectively acquired database included 209 consecutive patients. In 84 patients (40%) there was no intraoperative CSF leak and no postoperative CSF leak. In the 125 patients (60%) with an intraoperative CSF leak, 35 of them with high-flow leaks, there were 0 (0%) postoperative CSF leaks.nnnCONCLUSIONSnIt is possible to achieve a CSF leak rate of 0% by using this closure protocol. With proper experience, endoscopic skull base surgery should not be considered to have a higher CSF leak rate than open transcranial or microscopic transsphenoidal surgery.

Surgical outcomes using a medial-to-lateral endonasal endoscopic approach to pituitary adenomas invading the cavernous sinus

OBJECTnThis study details the extent of resection and complications associated with endonasal endoscopic surgery for pituitary tumors invading the cavernous sinus (CS) using a moderately aggressive approach to maximize extent of resection through the medial CS wall while minimizing the risk of cranial neuropathy and blood loss. Tumor in the medial CS was aggressively pursued while tumor in the lateral CS was debulked in preparation for radiosurgery.nnnMETHODSnA prospective surgical database of consecutive endonasal pituitary surgeries with verified CS invasion on intraoperative visual inspection was reviewed. The extent of resection as a whole and within the CS was assessed by an independent neuroradiologist using pre- and postoperative Knosp-Steiner (KS) categorization and volumetrics of the respective MR images. The extent of resection and clinical outcomes were compared for medial (KS 1-2) and lateral (KS 3-4) lesions.nnnRESULTSnThirty-six consecutive patients with pituitary adenomas involving the CS who had surgery via an endonasal endoscopic approach were identified. The extent of resection was 84.6% for KS 1-2 and 66.6% for KS 3-4 (p = 0.04). The rate of gross-total resection was 53.8% for KS 1-2 and 8.7% for KS 3-4 (p = 0.0006). Six patients (16.7%) had preoperative cranial neuropathies, and all 6 had subjective improvement after surgery. Surgical complications included 2 transient postoperative cranial neuropathies (5.6%), 1 postoperative CSF leak (2.8%), 1 reoperation for mucocele (2.8%), and 1 infection (2.8%).nnnCONCLUSIONSnThe endoscopic endonasal medial-to-lateral approach permits safe debulking of tumors in the medial and lateral CS. Although rates of gross-total resection are moderate, particularly in the lateral CS, the risk of permanent cranial neuropathy is extremely low and there is a high chance of improvement of preexisting deficits. This approach can also facilitate targeting for postoperative radiosurgery.

Sensitivity and specificity of intrathecal fluorescein and white light excitation for detecting intraoperative cerebrospinal fluid leak in endoscopic skull base surgery: a prospective study.

OBJECTIVEnThe intraoperative detection of CSF leaks during endonasal endoscopic skull base surgery is critical to preventing postoperative CSF leaks. Intrathecal fluorescein (ITF) has been used at varying doses to aid in the detection of intraoperative CSF leaks. However, the sensitivity and specificity of ITF at certain dosages is unknown.nnnMETHODSnA prospective database of all endoscopic endonasal procedures was reviewed. All patients received 25 mg ITF diluted in 10 ml CSF and were pretreated with dexamethasone and Benadryl. Immediately after surgery, the operating surgeon prospectively noted if there was an intraoperative CSF leak and fluorescein was identified. The sensitivity, specificity, and positive and negative predictive power of ITF for detecting intraoperative CSF leak were calculated. Factors correlating with postoperative CSF leak were determined.nnnRESULTSnOf 419 patients, 35.8% of patients did not show a CSF leak. Fluorescein-tinted CSF (true positive) was noted in 59.7% of patients and 0 false positives were encountered. CSF without fluorescein staining (false negative) was noted in 4.5% of patients. The sensitivity and specificity of ITF were 92.9% and 100%, respectively. The negative and positive predictive values were 88.8% and 100%, respectively. Postoperative CSF leaks only occurred in true positives at a rate of 2.8%.nnnCONCLUSIONSnITF is extremely specific and very sensitive for detecting intraoperative CSF leaks. Although false negatives can occur, these patients do not appear to be at risk for postoperative CSF leak. The use of ITF may help surgeons prevent postoperative CSF leaks by intraoperatively detecting and confirming a watertight repair.

Long-term quality of life after endonasal endoscopic resection of adult craniopharyngiomas

OBJECTnCraniopharyngiomas are benign parasellar tumors for which surgical removal, although potentially curative, often leads to morbidity with resulting decreases in quality of life (QOL). The endonasal endoscopic approach is a minimal-access technique for removing these tumors and may reduce postoperative morbidity. The QOL following this method for resection of craniopharyngiomas has not been documented.nnnMETHODSnThe authors reviewed a database of consecutive endonasal endoscopic surgeries done at Weill Cornell Medical College. Adult patients with histologically proven craniopharyngiomas were included who had completed either only postoperative (> 9 months) or both pre- and postoperative QOL forms, the Anterior Skull Base Quality of Life (ASBQ) questionnaire, and the 22-Item Sinonasal Outcome Test (SNOT-22). Rates of gross-total resection (GTR), complications, and visual and endocrine function were collected. Retrospective independence (Wen score) was also assigned. A contemporaneous group of patients undergoing endonasal endoscopic pituitary macroadenoma resection was used as a control.nnnRESULTSnThis study included 33 procedures performed in 31 patients. The average postoperative ASBQ score was 3.35 and the SNOT-22 score was 19.6. Better QOL was associated with GTR and postoperative radiation. Worse QOL was associated with persistent visual defects, hypopituitarism, tumor recurrence, increase in body mass index, and worsening Wen score. In a subset of 10 patients, both pre- and postoperative (> 9 months) QOL scores were obtained. Both ASBQ and SNOT-22 scores showed stability and a trend toward improvement, from 2.93 ± 0.51 to 2.96 ± 0.47 (ASBQ) and 23.7 ± 10.8 to 18.4 ± 11.6 (SNOT-22). Compared with 62 patients undergoing endoscopic pituitary macroadenoma resection, patients with craniopharyngiomas had worse postoperative QOL on the ASBQ (3.35 vs 3.80; p = 0.023) and SNOT-22 (19.6 vs 13.4; p = 0.12).nnnCONCLUSIONSnThis report of validated site-specific QOL following endoscopic surgery for craniopharyngiomas shows an overall maintenance of postoperative compared with preoperative QOL. Better QOL could be seen in patients with GTR and radiation therapy, and worse QOL was found in patients with visual or endocrine deficits. Nevertheless, patients with craniopharyngiomas still had worse QOL than those undergoing similar surgery for pituitary macroadenomas, confirming the worse prognosis of craniopharyngiomas even when removed via a minimally invasive approach. These measures should serve as benchmarks for comparison with open transcranial approaches to similar tumors.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guideline on Posttreatment Follow-up Evaluation of Patients With Nonfunctioning Pituitary Adenomas.

BACKGROUNDnNonfunctioning pituitary adenomas (NFPAs) are among the most common pituitary lesions and may present with hypopituitarism and/or hyperprolactinemia.nnnOBJECTIVEnTo review the existing literature as it pertains to preoperative endocrine assessment in the workup for NFPAs.nnnMETHODSnA systematic review methodology was utilized to identify and screen articles assessing the role and results of preoperative laboratory assessment in patients with NFPAs. The prevalence of individual pituitary hormonal axis deficiencies was reviewed.nnnRESULTSnTwenty-nine studies met inclusion criteria for analysis. No class I evidence was available, and all studies met criteria for class II evidence. Baseline serum laboratory assessment showed a prevalence of overall hypopituitarism in 37% to 85% of patients. The most common hormonal axis deficiency was growth hormone deficiency, prevalent in 61% to 100% of patients. The next most common deficit was hypogonadism, seen in 36% to 95% of patients. Adrenal insufficiency was diagnosed in 17% to 62% of patients. Finally, hypothyroidism was seen in 8% to 81% of patients. Hyperprolactinemia was seen in 25% to 65% of patients, with a mean level of 39 ng/mL and with a minority of patients exceeding a serum prolactin level of 200 ng/mL. No evidence supporting routine biomarker testing (eg, α-subunit or chromogranin A) or genetic testing in patients with sporadic NFPAs was available.nnnCONCLUSIONnDespite a paucity of class I evidence, multiple retrospective studies have demonstrated a high prevalence of hypopituitarism in patients with NFPAs. Routine endocrine analysis of all anterior pituitary axes to assess for hypopituitarism is recommended, with prolactin and insulin-like growth factor 1 evaluation also valuable to assess for hypersecretion states that might not be clinically suspected. The full guidelines document for this chapter can be located at https://www.cns.org/guidelines/guidelines-management-patients-non-functioning-pituitary-adenomas/Chapter_3.nnnABBREVIATIONSnGH, growth hormoneIGF-1, insulin-like growth factor 1NFPA, nonfunctioning pituitary adenoma.

Iterative Probabilistic Voxel Labeling: Automated Segmentation for Analysis of The Cancer Imaging Archive Glioblastoma Images

BACKGROUND AND PURPOSE: Robust, automated segmentation algorithms are required for quantitative analysis of large imaging datasets. We developed an automated method that identifies and labels brain tumor–associated pathology by using an iterative probabilistic voxel labeling using k-nearest neighbor and Gaussian mixture model classification. Our purpose was to develop a segmentation method which could be applied to a variety of imaging from The Cancer Imaging Archive. MATERIALS AND METHODS: Images from 2 sets of 15 randomly selected subjects with glioblastoma from The Cancer Imaging Archive were processed by using the automated algorithm. The algorithm-defined tumor volumes were compared with those segmented by trained operators by using the Dice similarity coefficient. RESULTS: Compared with operator volumes, algorithm-generated segmentations yielded mean Dice similarities of 0.92 ± 0.03 for contrast-enhancing volumes and 0.84 ± 0.09 for FLAIR hyperintensity volumes. These values compared favorably with the means of Dice similarity coefficients between the operator-defined segmentations: 0.92 ± 0.03 for contrast-enhancing volumes and 0.92 ± 0.05 for FLAIR hyperintensity volumes. Robust segmentations can be achieved when only postcontrast T1WI and FLAIR images are available. CONCLUSIONS: Iterative probabilistic voxel labeling defined tumor volumes that were highly consistent with operator-defined volumes. Application of this algorithm could facilitate quantitative assessment of neuroimaging from patients with glioblastoma for both research and clinical indications.

Combined Cranionasal Surgery for Spheno-Orbital Meningiomas Invading the Paranasal Sinuses, Pterygopalatine, and Infratemporal Fossa

OBJECTIVEnTo evaluate the efficacy of combining an endonasal endoscopic skull-base approach and repair with a transcranial orbitozygomatic approach for spheno-orbital meningiomas (SOMs).nnnMETHODSnThree patients with recurrent SOMs underwent combined orbitozygomatic and endonasal endoscopic surgery. In 2 patients both procedures were done in 1 operation and in 1 patient the endonasal surgery was done 2.5 months after the craniotomy. Extent of resection, complications, morbidity, and mortality were evaluated.nnnRESULTSnGross total resection was achieved in 1 patient and near total resection in the other 2 patients with tumor left in the cavernous sinus and parapharyngeal space. Two patients suffered cranial neuropathy from the transcranial surgery and the other developed a pseudomeningocele. There were no complications from the endonasal surgery. Patients having combined single setting cranionasal surgery were discharged on day 6 and 8, whereas the patient having only the endonasal component on a later date was discharged on day 2.nnnCONCLUSIONSnA combined cranionasal approach involving transcranial orbitozygomatic and endonasal endoscopic approaches is an effective 2-stage surgery for resecting SOMs invading into the sinuses and paranasal compartments. The ability to perform a multilayer closure involving a vascularized nasoseptal flap additionally decreases the risk of postoperative cerebrospinal fluid leak.

Imaging preictal hemodynamic changes in neocortical epilepsy.

OBJECTnThe ability to predict seizure occurrence is extremely important to trigger abortive therapies and to warn patients and their caregivers. Optical imaging of hemodynamic parameters such as blood flow, blood volume, and tissue and hemoglobin oxygenation has already been shown to successfully localize epileptic events with high spatial and temporal resolution. The ability to actually predict seizure occurrence using hemodynamic parameters is less well explored.nnnMETHODSnIn this article, the authors critically review data from the literature on neocortical epilepsy and optical imaging, and they discuss the preictal hemodynamic changes and their application in neurosurgery.nnnRESULTSnRecent optical mapping studies have demonstrated preictal hemodynamic changes in both human and animal neocortex.nnnCONCLUSIONSnOptical measurements of blood flow and oxygenation may become increasingly important for predicting and localizing epileptic events. The ability to successfully predict ictal onsets may be useful to trigger closed-loop abortive therapies.

The Impact of Age on Long-Term Quality of Life after Endonasal Endoscopic Resection of Skull Base Meningiomas

BACKGROUNDnMidline ventral skull base meningiomas may be amenable to an endonasal endoscopic approach, which has theoretical advantages and may help preserve quality of life (QOL) when compared with transcranial approaches.nnnOBJECTIVEnTo investigate the effect of age on QOL following endonasal endoscopic surgery, given the documented impact of age on QOL outcomes following transcranial resection of midline ventral skull base meningiomas.nnnMETHODSnWe reviewed a prospectively acquired database of endonasal endoscopic surgery for meningiomas. Inclusion criteria included patients who had completed long-term postoperative (≥6 months follow-up) QOL questionnaires (Anterior Skull Base Questionnaire [ASBQ] and Sino-Nasal Outcome Test [SNOT-22]). Postoperative QOL scores were also compared with preoperative QOL in a patient subset.nnnRESULTSnLong-term QOL data were available in 34 patients. Average postoperative ASBQ and SNOT-22 scores were 3.39 and 23.0, respectively. Better QOL was statistically associated with age <55 (P = .02). In a subset of patients, preoperative and postoperative ASBQ and SNOT-22 scores were compared. Only SNOT-22 scores significantly increased from 15.9 + 20.8 to 25.9 + 19.5 (P = .04).nnnCONCLUSIONnWe report the first study specifically evaluating long-term QOL after endonasal endoscopic resection of skull base meningiomas. QOL was decreased postoperatively in patients aged ≥55.nnnABBREVIATIONSnASBQ, Anterior Skull Base QuestionnaireGTR, gross total resectionQOL, quality of lifeSNOT-22, 22-item Sino-Nasal Outcome Test.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guideline on Preoperative Imaging Assessment of Patients With Suspected Nonfunctioning Pituitary Adenomas.

BACKGROUNDnThe authors reviewed published articles pertaining to the preoperative imaging evaluation of nonfunctioning pituitary adenomas (NFPAs) and formulated recommendations.nnnOBJECTIVEnTo provide an exhaustive review of published articles pertaining to the preoperative imaging evaluation of nonfunctioning pituitary adenomas.nnnMETHODSnThe MEDLINE database was queried for studies investigating imaging for the preoperative evaluation of pituitary adenomas.nnnRESULTSnFrom an initial search of 5598 articles, 122 articles were evaluated in detail and included in this article. Based on analysis of these articles, the recommendations are as follows: (1) High-resolution magnetic resonance imaging (level II) is recommended as the standard for preoperative assessment of nonfunctioning pituitary adenomas, but may be supplemented with CT (level III) and fluoroscopy (level III). (2) Although there are promising results suggesting the utility of magnetic resonance spectroscopy, magnetic resonance perfusion, positron emission tomography, and single-photon emission computed tomography, there is insufficient evidence to make formal recommendations pertaining to their clinical applications.nnnCONCLUSIONnThe authors identified 122 articles that form the basis of recommendations for preoperative imaging evaluation of nonfunctioning pituitary adenomas. The full guidelines document for this chapter can be located at https://www.cns.org/guidelines/guidelines-management-patients-non-functioning-pituitary-adenomas/Chapter_2.nnnABBREVIATIONSnCT, computed tomographyDWI, diffusion-weighted imagingMRI, magnetic resonance imagingNFPA, nonfunctioning pituitary adenoma.