Paul Klimo Jr. and Cody L. Nesvick
Paul Klimo Jr., Valerie Coon, and Douglas Brockmeyer
Os odontoideum was first described in the late 1880s and still remains a mystery in many respects. The genesis of os odontoideum is thought to be prior bone injury to the odontoid, but a developmental cause probably also exists. The spectrum of presentation is striking and ranges from patients who are asymptomatic or have only neck pain to those with acute quadriplegia, chronic myelopathy, or even sudden death. By definition, the presence of an os odontoideum renders the C1–2 region unstable, even under physiological loads in some patients. The consequences of this instability are exemplified by numerous cases in the literature in which a patient with os odontoideum has suffered a spinal cord injury after minor trauma. Although there is little debate that patients with os odontoideum and clinical or radiographic evidence of neurological injury or spinal cord compression should undergo surgery, the dispute continues regarding the care of asymptomatic patients whose os odontoideum is discovered incidentally. The authors' clinical experience leads them to believe that certain subgroups of asymptomatic patients should be strongly considered for surgery. These subgroups include those who are young, have anatomy favorable for surgical intervention, and show evidence of instability on flexion-extension cervical spine x-rays. This recommendation is bolstered by the fact that surgical fusion of the C1–2 region has evolved greatly and can now be done with considerable safety and success. When atlantoaxial instrumentation is used, fusion rates for os odontoideum should approach 100%.
Paul Klimo Jr. and Richard H. Schmidt
✓The elucidation of predictive factors of cerebral vasospasm following aneurysmal subarachnoid hemorrhage (SAH) is a major area of both clinical and basic science research. It is becoming clear that many factors contribute to this phenomenon. The most consistent predictor of vasospasm has been the amount of SAH seen on the postictal computed tomography scan. Over the last 30 years, it has become clear that the greater the amount of blood within the basal cisterns, the greater the risk of vasospasm. To evaluate this risk, various grading schemes have been proposed, from simple to elaborate, the most widely known being the Fisher scale. Most recently, volumetric quantification and clearance models have provided the most detailed analysis. Intraventricular hemorrhage, although not supported as strongly as cisternal SAH, has also been shown to be a risk factor for vasospasm.
Paul Klimo Jr. and Brian T. Ragel
ιˆητρός γάρ αˆνήρ πολλω∼ν αˆντάξιος αˆ´λλων ιˆούς τ´ εˆκτάμνειν εˆπί τ´ ηˆ´πια φάρμακα πάσσειν.
For a physician has the worth of many other warriors, both for the excision of arrows and for the administration of soothing drugs. Homer, Iliad XI.514–515
Ever since armed conflict has been used as a means to settle disputes among men, there have been those who have been tasked to mend the wounds that ravage a soldier's body from the weapons of war. The Iliad portrays the pivotal 10th year of the legendary Trojan War, during which a schism in the Greek leadership prolongs the extended siege of the city of Troy. In the midst of this martial epic come the lines quoted above, quietly attesting to the value of the military physician, even under the crude conditions of the Greek Dark Age. They are uttered by Idomeneus, one of the foremost Greeks, when he is enjoining one of his comrades, Nestor, to rescue the injured Greek physician Machaon and take him back from the line to treat his wounds. He is afraid that Machaon will be captured by the Trojans, a loss far greater than that of any other single warrior.
Duty to country has helped shape the careers of many neurosurgeons, including iconic US figures such as Harvey Cushing and Donald Matson. This issue of Neurosurgical Focus celebrates the rich history of military neurosurgery from the wars of yesterday to the conflicts of today. We have been humbled by the tremendous response to this topic. The 25 articles within this issue will provide the reader with both a broad and an in-depth look at the many facets of military neurosurgery. We have attempted to group articles based on their predominant topic. We also encourage our audience to read other recently published articles. –4
The first 8 articles relate to the current conflicts in Afghanistan and Iraq. The lead article, written by Randy Bell and colleagues from the National Naval Medical Center and Walter Reed Army Medical Center, discusses what is arguably one of the most important contributions by military neurosurgeons from these 2 conflicts: the rapid and aggressive use of decompressive craniectomies. This is followed by articles on decompressive craniectomy techniques by Ragel and colleagues and cranioplasty outcomes by Stephens and colleagues. After reading these articles, the reader will come away with an appreciation of the often complex nature of wartime penetrating and closed-head injuries and the remarkable recovery that many injured soldiers make with time.
Incidentally discovered lesions
Cormac O. Maher, Paul Klimo Jr., and Edward R. Smith
Paul Klimo Jr. and John R. W. Kestle
✓The choice of outcome (or outcomes) and their measurement are critical for a sound clinical trial. Surgeons have traditionally measured simple outcomes such as death, duration of survival, or tumor recurrence but have recently developed more sophisticated measures of the effect of an intervention. Many outcome measures require a lengthy maturation process, which includes a determination of the instrument's validity, reliability, and sensitivity; thus, using established instruments rather than creating new ones is recommended. The authors illustrate several guidelines for the determination of appropriate outcome measures by using examples from their experience and describe several outcome measures that can be used in pediatric neurosurgery. These include general outcome measures such as the Pediatric Evaluation of Disability Inventory and the Functional Independence Measure for Children, which measure physical function and independence in chronically ill and disabled children as well as disease-specific measures for hydrocephalus (Hydrocephalus Outcome Questionnaire), cerebral palsy (gross motor function and performance measures), head injury (Pediatric Cerebral Performance Category and Children's Coma Scale), and oncology (Pediatric Cancer Quality-of-Life Inventory).
Michael Finn, Paul Klimo Jr., and William T. Couldwell
✓Dural arteriovenous fistulas (dAVFs) are acquired direct arteriovenous shunts that often drain into the dural venous sinus. Treatment options generally involve disrupting the abnormal vascular conduits by using a combination of modalities, including surgical disconnection, radiosurgery, and transarterial and transvenous embolization. Often these modalities provide only partial treatment of fistulous lesions, and thus the fistula recurs and symptoms result. The authors report on a novel surgical technique in which the involved venous sinuses are skeletonized and an interpositional dural substitute is placed between the disconnected sinus and native dura mater and over the pial surface adjacent to the sinus. The technique, which is demonstrated in an illustrative case, is intended to preserve native venous drainage and to prevent recruitment of new vascularization to the venous sinus postoperatively. The authors have not observed reconstitution of fistulas over areas treated with this technique, which offers the advantage of inhibiting vascular ingrowth (refistulization) while maintaining venous sinus patency.