- Department of Medicine, Division of Biostatistics and Epidemiology, South Carolina, USA
- Department of Neurosciences, Division of Neurosciences, Division of Neurosurgery, Medical University of South Carolina, Charleston, South Carolina, USA
Correspondence Address:
Joyce S. Nicholas
Department of Neurosciences, Division of Neurosciences, Division of Neurosurgery, Medical University of South Carolina, Charleston, South Carolina, USA
DOI:10.4103/2152-7806.66458
© 2010 Nicholas JS. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.How to cite this article: Nicholas JS, Patel SJ. Pulsatile arterial compression of cranial nerves. Surg Neurol Int 16-Jul-2010;1:28
How to cite this URL: Nicholas JS, Patel SJ. Pulsatile arterial compression of cranial nerves. Surg Neurol Int 16-Jul-2010;1:28. Available from: http://sni.wpengine.com/surgicalint_articles/pulsatile-arterial-compression-of-cranial-nerves/
The authors are to be commended for their observations on patients undergoing retromastoid craniectomy with microvascular decompression of the right ventrolateral medulla (VLM) and vagus nerve for type 2 diabetes mellitus. Seven of the 10 patients observed demonstrated overall glycemic control that either improved or did not worsen at the 12-month postoperative follow-up visit.
These observations point the way to further questions that need to be answered to conclude definitively that pulsatile arterial compression of the right VLM is an independent risk factor for type 2 diabetes mellitus. As stated by the authors, a neurogenic basis for various cranial nerve hyperactive syndromes has long been postulated in the literature, with the first on essential hypertension made by Dr. Jannetta in the 1970s. Animal studies confirmed the presence of a subpial catecholamine-synthesizing neuronal group (C1) in the rostral ventrolateral medulla, which produces a transient pressor response when stimulated electrically, chemically or mechanically.[
Like Dr. Jannetta’s earlier observations on essential hypertension, the observations presented in the manuscript “Type 2 Diabetes Mellitus: A Central Nervous System Etiology” are valuable starting points for questions related to the exact location of arterial compression relevant to type 2 diabetes mellitus, the best experimental measure of response, and the subset of patients most likely to benefit from microvascular decompressive surgery. The authors have made a start in this direction by observing that non-obese patients with type 2 diabetes mellitus appear to respond better to decompression than obese patients. We encourage their continued efforts and those of other researchers in addressing those questions raised by this valuable contribution to our understanding of type 2 diabetes mellitus and its treatment.
References
1. Aicher SA, Saravay RH, Cravo S, Jeske I, Morrison SF, Reis DJ. Monosynaptic projections from the nucleus tractus solitarii to C1 adrenergic neurons in the rostral ventrolateral medulla: Comparison with input from the caudal ventrolateral medulla. J Comp Neurol. 1996. 373: 62-75
2. Coffee RE, Nicholas JS, Egan BM, Rumboldt Z, D’Agostino S, Patel SJ. Arterial compression of the retro-olivary sulcus of the medulla in essential hypertension: A multivariate analysis. J Hypertens. 2005. 23: 2027-31
3. Dampney RA, Goodchild AK, Robertson LG, Montgomery W. Role of ventrolateral medulla in vasomotor regulation: A correlative anatomical and physiological study. Brain Res. 1982. 249: 223-35
4. Dormer KJ, Bedford TG. Cardiovascular control by the rostral ventrolateral medulla in the conscious dog. Prog Brain Res. 1989. 81: 265-77
5. Gajjar D, Egan B, Cure J, Rust P, VanTassel P, Patel SJ. Vascular compression of the rostral ventrolateral medulla in sympathetic mediated essential hypertension. Hypertension. 2000. 36: 78-82
6. Halliday GM, LiYW , Joh TH, Cotton RG, Howe PR, Geffen LB. Distribution of monoamine-synthesizing neurons in the human medulla oblongata. J Comp Neurol. 1988. 273: 301-17
7. Jannetta P, Segal R, Wolfson S, Dujovny M, Semba A, Cook E. Neurogenic hypertension: Etiology and surgical treatment. II. Observation in an experimental non-human primate model. Ann Surg. 1985. 202: 253-61
8. Nicholas JS, D’Agostino SJ, Patel SJ. Arterial compression of the retro-olivary sulcus of the ventrolateral medulla in essential hypertension and diabetes. Hypertension. 2005. 46: 982-5
9. Patel SJ, Sribnick E, Nicholas J, Egan B. Vasomotor and sympathetic mapping of the human ventro-lateral medulla. Am J Hypertens. 2003. 16: A220-1
10. Ross CA, Ruggiero DA, Park DH, Tong HJ, Sved AF, Fernandez-Pardal J. Tonic vasomotor control by the rostral ventrolateral medulla: Effect of electrical or chemical stimulation of the area containing C1 adrenaline neurons on arterial pressure, heart rate, and plasma catecholamines and vasopressin. J Neurosci. 1984. 4: 474-94
11. Welzig CM, Vincent DJ, Vera C, Egan B, Patel SJ.editors. Mapping of cardiovascular control functions along the ventrolateral medullary surface (VLMS) in humans. Sixth Annual Frontiers in Neuroscience Research Day, Charleston, SC, 2005. p.