Letter to the Editor, Regarding “A Gaze Beyond the Surface”

To the Editor:

We read with great interest the article by Wilkinson et al published at the July issue of Neurosurgery entitled “Failure of Percutaneous Remodeling of the Ligamentum Flavum and Lamina for Neurogenic Claudication”¹ and the hot discussion that followed the presentation of the study’s results.^2,3

The initial reaction of the majority of the readers after analyzing such a study is to focus on the effectiveness (or lack of) and the possible role of the new proposed technique (minimally invasive lumbar decompression, so-called MILD technique) in the treatment of lumbar spinal stenosis, and after that, quickly position themselves in 1 of the 2 fronts and passionately defend their own opinion based on their previous clinical experience and personal beliefs. Nevertheless, we truly believe that the great contribution of such a small series about a still primitive and underdeveloped technique is not what this series shows “to” us, but what it shows “about” us.

Without taking any judgmental attitude regarding the possible (or more likely impossible) long-term benefits of the aforementioned technique, the clear discrepancy in the results found by such a study should flash a bright red light and alert us that something is wrong: not with the data obtained, not with the methods of the study, maybe neither with the new proposed technique, but probably with what we believe we know (and most likely do not) about the pathophysiology, imaging, and clinical outcomes of lumbar spinal canal stenosis.

Letter to the Editor, Regarding “Optimal Target of Deep Brain Stimulation for Essential Tremor”

To the Editor:

I read with interest the article by Sandvik et al.¹ The authors performed a retrospective nonrandomized study on 2 groups of patients (17 ventral intermediate nucleus [Vim]/19 posterior subthalamic area [PSA]) undergoing deep brain stimulation for Essential Tremor. The Vim was the target for patients undergoing surgery from 1997 to 2004. The PSA was the target for those patients operated on from 2004 to 2007. The effect of optimal deep brain stimulation on tremor was judged by a >90% reduction in tremor. The contacts yielding the best results were in the PSA (Zi/Raprl/Forels field H) in 42.5% and in Vim in 17.5%. This was determined by postoperative computed tomography coregistered to the Schaltenbrand and Wahren atlas. The averaged co-ordinates were given for the >90% reduction of tremor in the PSA and Vim. Specifically, the latter target’s y coordinate behind the midpoint of the intercommissural line seems somewhat anterior The authors offered the belief (and justifiably so) that the clinical effect may be generated by an overlap of stimulation of more than 1 electrode contact.

Response Letter to the Editor, Regarding “Focus of Future Neurosurgical Training Research”

We agree with Simon and Liu’s comments, and these comments underscore the complexity of neurosurgical education and training in the current climate of Accreditation Council for Graduate Medical Education duty-hour restrictions. Although our study may not provide a causal relationship between duty-hour restrictions and adverse outcomes in neurosurgical trauma patients, it does demonstrate that the original motivations for the duty-hour restrictions, reduction of medical errors by reducing resident fatigue, have not met their aim. It is crucial that further study and open discussion continue on these highly critical issues.

Hoh, Brian L.

Gainesville, Florida

Letter to the Editor, Regarding “Focus of Future Neurosurgical Training Research Must Keep Goal in Mind”

To the Editor:

We would like to commend the authors of “Higher Complications and No Improvement in Mortality in the ACGME Resident Duty-Hour Restriction Era: An Analysis of More Than 107 000 Neurosurgical Trauma Patients in the Nationwide Inpatient Survey Database” for their important contribution to the ongoing debate of how best to train neurosurgeons. As the authors duly note, the majority of neurosurgeons are disappointed with the educational impact of duty-hour restrictions.¹ Only when armed with data demonstrating that these regulations not only do not achieve their stated goal, but also adversely impact training can neurosurgical educators hope to have them adjusted.

Although investigators can be specific about their conclusions, how data are interpreted in the public sphere to dictate policy can vary greatly. We applaud the authors’ efforts, but we feel that simply demonstrating an association between duty-hour regulation and poor outcomes, no matter how skillfully done, does not necessarily provide a basis for revising those hours, especially in the eyes of those who advocated for the hour changes in the first place. In 1905, Upton Sinclair authored the The Jungle, in which he attempted to illustrate the dehumanizing effects of industrial capitalism by describing the meat-packing industry in Chicago. His descriptions were so vivid, however, that it resulted not in labor reform, but in the Pure Food and Drug and Meat Inspection Act. The author lamented, “I aimed at the public’s heart and by accident hit its stomach.”²

Letter to the Editor, Regarding “Covered Carotid Stents”

To the Editor:

We read with interest the article by McDougall et al.¹ We think that 2 issues are important. First, the feeding arteries of the carotid body tumors arose from different locations. Paragangliomas not only receive their blood supply from the carotid arteries but also can be vascularized by the vertebral arteries, deep cervical artery, and thyrocervical trunk.² Stenting internal carotid artery is not guaranteed devascularization of tumor. Second, safe resection of these tumors is maintained by cleavage of the tumor mass from the carotid arteries. Vessel-rich tumoral tissue tightly surrounds the carotid arteries, especially in Shamblin stage III. The internal carotid artery must be partially compressed to separate from the stretched vessel network of the carotid body tumor where it is surrounded. The internal carotid artery including a stent may unsuitable for surgical manipulation such as compression and pulling.

Sunar, Hasan; Taş, Serpil Gezer

Istanbul, Turkey

References
1. McDougall CM, Liu R, Chow M. Covered carotid stents as an adjunct in the surgical treatment of carotid body tumors: a report of two cases and a review of the literature. Neurosurgery. 2012;71:onsE182–onsE185.

2. van den Berg R, Wasser MN, van Gils AP, van der Mey AG, Hermans J, van Buchem MA. Vascularization of head and neck paragangliomas: comparison of three MR angiographic techniques with digital subtraction angiography. AJNR Am J Neuroradiol. 2000;21(1):162–170.