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Kurt R. Lehner and Michael Schulder

Sir Victor Horsley was a pioneering British neurosurgeon known for his numerous neurosurgical, scientific, and sociopolitical contributions. Although word of these surgical and scientific achievements quickly spread throughout Europe and North America in the late 19th century, much of modern neurosurgery’s view of Horsley has been colored by a single anecdote from John Fulton’s biography of Harvey Cushing. In this account, Cushing observes a frenetic Horsley hastily removing a Gasserian ganglion from a patient in the kitchen of a British mansion. Not long after, Cushing left Britain saying that he had little to learn from British neurosurgery. The authors of this paper examined contemporary views of Horsley to assess what his actual reputation was in the US and Canada. The authors conducted a thorough search of references to Horsley using the following sources: American surgical and neurosurgical textbooks; major biographies; diary entries and letters; PubMed; newspaper articles; and surgical and neurosurgical texts. The positive reception of his work is corroborated by invitations for Horsley to speak in America. Research additionally revealed that Horsley had numerous personal and professional relationships with prominent Americans in medicine, including William Osler, John Wheelock Elliot, Ernest Sachs, and (yes) Harvey Cushing. Horsley’s contributions to medicine and science were heavily reported in American newspapers; outside of neurosurgery, his strong opposition to the antivivisectionists and his support for alcohol prohibition were widely reported in popular media. Horsley’s contributions to neurosurgery in America are undeniable. Writings from and about prominent Americans reveal that he was viewed favorably by those who had met him. Frequent publication of his views in the American media suggests that medical professionals and the public in the US valued his contributions on scientific as well as social issues. Horsley died too young, but not without the international recognition that was rightly his.

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Kurt R. Lehner, Erin M. Yeagle, Miklos Argyelan, Zoltán Klimaj, Victor Du, Pierre Megevand, Sean T. Hwang and Ashesh D. Mehta

Objective

Disconnection of the cerebral hemispheres by corpus callosotomy (CC) is an established means to palliate refractory generalized epilepsy. Laser interstitial thermal therapy (LITT) is gaining acceptance as a minimally invasive approach to treating epilepsy, but this method has not been evaluated in clinical series using established methodologies to assess connectivity. The goal in this study was to demonstrate the safety and feasibility of MRI-guided LITT for CC and to assess disconnection by using electrophysiology- and imaging-based methods.

Methods

Retrospective chart and imaging review was performed in 5 patients undergoing LITT callosotomy at a single center. Diffusion tensor imaging and resting functional MRI were performed in all patients to assess anatomical and functional connectivity. In 3 patients undergoing simultaneous intracranial electroencephalography monitoring, corticocortical evoked potentials and resting electrocorticography were used to assess electrophysiological correlates.

Results

All patients had generalized or multifocal seizure onsets. Three patients with preoperative evidence for possible lateralization underwent stereoelectroencephalography depth electrode implantation during the perioperative period. LITT ablation of the anterior corpus callosum was completed in a single procedure in 4 patients. One complication involving misplaced devices required a second procedure. Adequacy of the anterior callosotomy was confirmed using contrast-enhanced MRI and diffusion tensor imaging. Resting functional MRI, corticocortical evoked potentials, and resting electrocorticography demonstrated functional disconnection of the hemispheres. Postcallosotomy monitoring revealed lateralization of the seizures in all 3 patients with preoperatively suspected occult lateralization. Four of 5 patients experienced > 80% reduction in generalized seizure frequency. Two patients undergoing subsequent focal resection are free of clinical seizures at 2 years. One patient developed a 9-mm intraparenchymal hematoma at the site of entry and continued to have seizures after the procedure.

Conclusions

MRI-guided LITT provides an effective minimally invasive alternative method for CC in the treatment of seizures associated with drop attacks, bilaterally synchronous onset, and rapid secondary generalization. The disconnection is confirmed using anatomical and functional neuroimaging and electrophysiological measures.

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Zach Pennington, Jeff Ehresman, Ethan Cottrill, Daniel Lubelski, Kurt Lehner, James Feghali, A. Karim Ahmed, Andrew Schilling and Daniel M. Sciubba

Accurate prediction of patient survival is an essential component of the preoperative evaluation of patients with spinal metastases. Over the past quarter of a century, a number of predictors have been developed, although none have been accurate enough to be instituted as a staple of clinical practice. However, recently more comprehensive survival calculators have been published that make use of larger data sets and machine learning to predict postoperative survival among patients with spine metastases. Given the glut of calculators that have been published, the authors sought to perform a narrative review of the current literature, highlighting existing calculators along with the strengths and weaknesses of each. In doing so, they identify two “generations” of scoring systems—a first generation based on a priori factor weighting and a second generation comprising predictive tools that are developed using advanced statistical modeling and are focused on clinical deployment. In spite of recent advances, the authors found that most predictors have only a moderate ability to explain variation in patient survival. Second-generation models have a greater prognostic accuracy relative to first-generation scoring systems, but most still require external validation. Given this, it seems that there are two outstanding goals for these survival predictors, foremost being external validation of current calculators in multicenter prospective cohorts, as the majority have been developed from, and internally validated within, the same single-institution data sets. Lastly, current predictors should be modified to incorporate advances in targeted systemic therapy and radiotherapy, which have been heretofore largely ignored.

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Jonathan A. Forbes, Matei Banu, Kurt Lehner, Malte Ottenhausen, Emanuele La Corte, Andrew F. Alalade, Edgar G. Ordóñez-Rubiano, Jeffrey P. Greenfield, Vijay K. Anand and Theodore H. Schwartz

OBJECTIVE

Epidermoid cysts (ECs) commonly extend to involve the ventral cisterns of the cranial base. When present, symptoms arise due to progressive mass effect on the brainstem and adjacent cranial nerves. Historically, a variety of open microsurgical approaches have been used for resection of ECs in this intricate region. In recent years, the endoscopic endonasal approach (EEA) has been proposed as an alternative corridor that avoids crossing the plane of the cranial nerves. To date, there is a paucity of data in the literature regarding the safety and efficacy of the EEA in the treatment of ECs of the ventral cranial base.

METHODS

The authors reviewed a prospectively acquired database of EEAs for resection of ECs over 8 years at Weill Cornell, NewYork-Presbyterian Hospital. All procedures were performed by the senior authors. Standardized clinical and radiological parameters were assessed before and after surgery. Statistical tests were used to determine the impact of previous surgery and tumor volume on extent of resection and recurrence as well as the method of closure on rate of CSF leak.

RESULTS

Between January 2009 and February 2017, 7 patients (4 males and 3 females; age range 16–70 years) underwent a total of 8 surgeries for EC resection utilizing the EEA. Transplanum and transclival extensions were performed in 3 and 5 patients, respectively. Methods of closure incorporated a gasket seal in 6 of 8 procedures and a nasoseptal flap in 7 of 8 procedures. Gross-total resection (GTR) was achieved in 43% of patients, and near-total resection (> 95%) was obtained in another 43%. Complications included diabetes insipidus (n = 2), postoperative CSF leak (n = 2), transient third cranial nerve palsy (n = 1), and epistaxis (n = 1). With a mean follow-up of 43.5 months, recurrence has been observed in 2 of 7 patients. In 1 case, reoperation for recurrence was required 71 months following the initial surgery. Use of the gasket-seal technique with nasoseptal flap coverage significantly correlated with the absence of postoperative CSF leakage (p = 0.018). GTR was achieved in 25% of the patients who had prior surgeries and in 50% of patients without previous resections. The mean volume of cysts in which GTR was achieved (4.3 ± 1.8 cm3) was smaller than that in which subtotal or near-total resection was achieved (12.2 ± 11 cm3, p = 0.134).

CONCLUSIONS

The EEA for resection of ECs of the ventral cranial base is a safe and effective operative strategy that avoids crossing the plane of the cranial nerves. In the authors’ experience, gasket-seal closure with nasoseptal flap coverage has been associated with a decreased risk of postoperative CSF leakage.