Three-dimensional Autostereoscopic Display for Neurosurgery Application

poster abstractThree-dimensional (3D) imaging technology has recently been successfully used in Neurosurgery. These new experiments with several types of brain surgeries performed in 3D show promising results in improving the training of clinicians in new techniques. In the surgical theater, the image data is captured by two separate imagers attached to the microscope, corresponding to a left view and a right view. These images are then displayed on a 3D television. Recent experiments performed in the operating theater use glasses in sync with the view of the left and right microscope image outputs to show apparent 3D to the clinicians. A well-known concern with 3D technology is eye-strain and fatigue of the viewer over hours of viewing. We report initial results of 3D research for the surgery application using an autostereoscopic (no-glasses) display, which reduces 3D fatigue. The left-right view of the surgical task was captured, processed, and is shown successfully on an autostereoscopic display. Initial subjective evaluation by the surgeon indicates that the images are substantially similar to viewing through the microscope directly. Our next steps will be to provide real-time autostereoscopic (no-glasses) viewing in the operating theater for evaluation and assessment. The 3D display with surgical highlights will be shown in the poster session

The Signature Center Initiative for the Cure of Glioblastoma

poster abstractGlioblastoma multiforme (GBM, World Health Organization/WHO grade IV) is the most common form of brain cancer in the central nervous system. Although conventional treatment-surgery, radiation, and temozolomide-is somewhat effective in adults, overall survival is still < 15 months. In pediatric patients, morbidity due to GBM is the highest among all pediatric cancers. In the context of brain cancers, new and existing therapeutics typically fail due to heterogeneity of genetic mutations within tumors, and because biologically effective doses of drug cannot be delivered to the primary site and invasive perimeter of the tumor due to the blood brain barrier. The Signature Center Initiative to Cure GBM is a funding mechanism that supports a research portal to foster investigations of the Brain Tumor Working Group for development of effective treatments for the eradication of GBM. The overall mission of the Signature Center Initiative is to: 1. Interrogate the molecular mechanisms of GBM biology and develop interventions that result in improved duration and quality of life for our patients. 2. Stimulate consistent and productive exchange of ideas between clinicians and basic scientists while employing bench-to-bedside and bedside-to-bench strategies to generate and prioritize scientific questions. 3. Provide infrastructure and mentorship needed to successfully compete for external funding. 4. Engage the community through patient advocacy to positively impact brain cancer patient outcomes and enhance philanthropic initiatives. The Brain Tumor Working Group brings together scientists committed to engaging in a team-based approach to study GBM biology. Infrastructure required to advance in vivo humanized intracranial tumor models, drug delivery, target validation, and development of new therapeutic strategies are in place. Additionally a patient sample pipeline to obtain, analyze, and distribute primary patient GBM specimens from the operating room to the research laboratory has been established. In year one of funding, over $70,000 in pilot project funding derived from the Signature Center Initiative and private donations has been distributed to the membership. The Brain Tumor Working Group meets in both small and large group formats to strategize experimental design and grant submissions. A network of basic scientists and clinicians has been developed that provides an effective forum for addressing clinically relevant questions related to GBM. A team-based approach, scientific expertise, and continued development of infrastructure provide our membership with a critical foundation to obtain new knowledge related to understanding how GBM cells evade therapy. In the future, this information can be applied to development of effective treatments that will cure GBM

The pursuit of a cholesteatoma by harvey cushing: staged approach to a complex skull base tumor

Objective The evolution of neurosurgical techniques during Harvey Cushing's practice was immense. The authors illustrate this evolution using archived historical records from Harvey Cushing. Setting Historical patient records retained by the Cushing Center at Yale University Department of Neurosurgery. Design The authors present the case of one of Cushing's patients with a cholesteatoma. Results Cushing's surgical treatment of a cholesteatoma extending into the skull base is an example of his meticulous documentation and accelerated surgical techniques. Conclusions This case demonstrates how neurosurgical techniques advanced in the management of complex skull base tumors via a staged approach through the middle and posterior fossae at a time long before the development of modern skull base surgery

Transsylvian selective amygdalohippocampectomy for treatment of medial temporal lobe epilepsy: Surgical technique and operative nuances to avoid complications

Background: A number of different surgical techniques are effective for treatment of drug-resistant medial temporal lobe epilepsy. Of these, transsylvian selective amygdalohippocampectomy (SA), which was originally developed to maximize temporal lobe preservation, is arguably the most technically demanding to perform. Recent studies have suggested that SA may result in better neuropsychological outcomes with similar postoperative seizure control as standard anterior temporal lobectomy, which involves removal of the lateral temporal neocortex. Methods: In this article, the authors describe technical nuances to improve the safety of SA. Results: Wide sylvian fissure opening and use of neuronavigation allows an adequate exposure of the amygdala and hippocampus through a corticotomy within the inferior insular sulcus. Avoidance of rigid retractors and careful manipulation and mobilization of middle cerebral vessels will minimize ischemic complications. Identification of important landmarks during amygdalohippocampectomy, such as the medial edge of the tentorium and the third nerve within the intact arachnoid membranes covering the brainstem, further avoids operator disorientation. Conclusion: SA is a safe technique for resection of medial temporal lobe epileptogenic foci leading to drug-resistant medial temporal lobe epilepsy

External cortical landmarks and measurements for the temporal horn: Anatomic study with application to surgery of the temporal lobe

BACKGROUND: The location of the temporal horn is important to neurosurgeons during procedures such as amygdalohippocampectomy and intraventricular electrode placement for temporal lobe seizure monitoring. However, sometimes the temporal horn is difficult to localize, especially without neuronavigation. The authors aimed to better localize this structure using superficial anatomic landmarks. METHODS: Twenty-two brain halves were dissected from the midline, and the fornix identified and followed toward the left and right temporal horns. Once the temporal horn was isolated from a mesial approach, 6-cm long needles were placed into its anterior and posterior walls of the temporal horn and passed laterally from the axial plane to the cortical surface. Pin exit sites were marked externally and measurements taken between the outer temporal lobe cortex and the underlying temporal horn. RESULTS: No statistical differences were noted between left and right sides. The temporal horn was generally directed anteroinferiorly and best marked externally by the inferior temporal sulcus. The mean length of the temporal horn was 4.4 cm. Mean distance from anterior temporal tip to anterior wall of the temporal horn was 3.3 cm. The mean distance from the anterior temporal tip to the posterior wall of the temporal horn was 7 cm. The anterior wall of the temporal horn was a mean of 3 mm superior to the inferior temporal sulcus. The posterior wall was a mean of 1.2 cm superior to the inferior temporal sulcus. CONCLUSIONS: These landmarks and measurements may help neurosurgeons better localize this part of the lateral ventricular system

Cushing's ulcer: Further reflections

BACKGROUND: Brain tumors, traumatic head injury, and other intracranial processes including infections, can cause increased intracranial pressure and lead to overstimulation of the vagus nerve. As a result, increased secretion of gastric acid may occur which leads to gastro-duodenal ulcer formation known as Cushing's ulcer. METHODS: A review of original records of Dr. Harvey Cushing's patients suffering from gastro-duodenal ulcers was performed followed by a discussion of the available literature. We also reviewed the clinical records of the patients never reported by Cushing to gain his perspective in describing this phenomenon. Dr. Cushing was intrigued to investigate gastro-duodenal ulcers as he lost patients to acute gastrointestinal perforations following successful brain tumor operations. It is indeed ironic that Harvey Cushing developed a gastro-duodenal ulcer in his later years with failing health. RESULTS: Clinically shown by Cushing's Yale Registry, a tumor or lesion can disrupt this circuitry, leading to gastroduodenal ulceration. Cushing said that it was "reasonable to believe that the perforations following posterior fossa cerebellar operations were produced in like fashion by an irritative disturbance either of fiber tracts or vagal centers in the brain stem." CONCLUSION: Harvey Cushing's pioneering work depicted in his Yale registry serves as a milestone for continuing research that can further discern this pathway

Posterior Interhemispheric Transfalcine Transprecuneus Approach for Microsurgical Resection of Peri-Atrial Lesions: Indications, Technique, and Outcomes

OBJECT Surgical exposure of the peritrigonal or periatrial region has been challenging due to the depth of the region and overlying important functional cortices and white matter tracts. The authors demonstrate the operative feasibility of a contralateral posterior interhemispheric transfalcine transprecuneus approach (PITTA) to this region and present a series of patients treated via this operative route. METHODS Fourteen consecutive patients underwent the PITTA and were included in this study. Pre- and postoperative clinical and radiological data points were retrospectively collected. Complications and extent of resection were reviewed. RESULTS The mean age of patients at the time of surgery was 39 years (range 11–64 years). Six of the 14 patients were female. The mean duration of follow-up was 4.6 months (range 0.5–19.6 months). Pathology included 6 arteriovenous malformations, 4 gliomas, 2 meningiomas, 1 metastatic lesion, and 1 gray matter heterotopia. Based on the results shown on postoperative MRI, 1 lesion (7%) was intentionally subtotally resected, but ≥ 95% resection was achieved in all others (93%) and gross-total resection was accomplished in 7 (54%) of 13. One patient (7%) experienced a temporary approach-related complication. At last follow-up, 1 patient (7%) had died due to complications of his underlying malignancy unrelated to his cranial surgery, 2 (14%) demonstrated a Glasgow Outcome Scale (GOS) score of 4, and 11 (79%) manifested a GOS score of 5. CONCLUSIONS Based on this patient series, the contralateral PITTA potentially offers numerous advantages, including a wider, safer operative corridor, minimal need for ipsilateral brain manipulation, and better intraoperative navigation and working angles

The Intramuscular Course of the Greater Occipital Nerve: Novel Findings with Potential Implications for Operative Interventions and Occipital Neuralgia

Background: A better understanding of the etiologies of occipital neuralgia would help the clinician treat patients with this debilitating condition. Since few studies have examined the muscular course of the greater occipital nerve (GON), this study was performed. Methods: Thirty adult cadaveric sides underwent dissection of the posterior occiput with special attention to the intramuscular course of the GON. Nerves were typed based on their muscular course. Results: The GON traveled through the trapezius (type I; n = 5, 16.7%) or its aponeurosis (type II; n = 15, 83.3%) to become subcutaneous. Variations in the subtrapezius muscular course were found in 10 (33%) sides. In two (6.7%) sides, the GON traveled through the lower edge of the inferior capitis oblique muscle (subtype a). On five (16.7%) sides, the GON coursed through a tendinous band of the semispinalis capitis, not through its muscular fibers (subtype b). On three (10%) sides the GON bypassed the semispinalis capitis muscle to travel between its most medial fibers and the nuchal ligament (subtype c). For subtypes, eight were type II courses (through the aponeurosis of the trapezius), and two were type I courses (through the trapezius muscle). The authors identified two type IIa courses, four type IIb courses, and two type IIc courses. Type I courses included one type Ib and one type Ic courses. Conclusions: Variations in the muscular course of the GON were common. Future studies correlating these findings with the anatomy in patients with occipital neuralgia may elucidate nerve courses vulnerable to nerve compression. This enhanced classification scheme describes the morphology in this region and allows more specific communications about GON variations

Diagnosis and evaluation of intracranial arteriovenous malformations

BACKGROUND: Ideal management of intracranial arteriovenous malformations (AVMs) remains poorly defined. Decisions regarding management of AVMs are based on the expected natural history of the lesion and risk prediction for peritreatment morbidity. Microsurgical resection, stereotactic radiosurgery, and endovascular embolization alone or in combination are all viable treatment options, each with different risks. The authors attempt to clarify the existing literature's understanding of the natural history of intracranial AVMs, and risk-assessment grading scales for each of the three treatment modalities. METHODS: The authors conducted a literature review of the existing AVM natural history studies and studies that clarify the utility of existing grading scales available for the assessment of peritreatment risk for all three treatment modalities. RESULTS: The authors systematically outline the diagnosis and evaluation of patients with intracranial AVMs and clarify estimation of the expected natural history and predicted risk of treatment for intracranial AVMs. CONCLUSION: AVMs are a heterogenous pathology with three different options for treatment. Accurate assessment of risk of observation and risk of treatment is essential for achieving the best outcome for each patient

The Signature Center Initiative for the Cure of Glioblastoma

poster abstractGlioblastoma multiforme (GBM, World Health Organization/WHO grade IV) is the most common form of brain cancer in the central nervous system. Although conventional treatment-surgery, radiation, and temozolomide-is somewhat effective in adults, overall survival is still < 15 months. In pediatric patients, morbidity due to GBM is the highest among all pediatric cancers. In the context of brain cancers, new and existing therapeutics typically fail due to heterogeneity of genetic mutations within tumors, and because biologically effective doses of drug cannot be delivered to the primary site and invasive perimeter of the tumor due to the blood brain barrier. The Signature Center Initiative to Cure GBM is a funding mechanism that supports a research portal to foster investigations of the Brain Tumor Working Group for development of effective treatments for the eradication of GBM. The overall mission of the Signature Center Initiative is to: 1. Interrogate the molecular mechanisms of GBM biology and develop interventions that result in improved duration and quality of life for our patients. 2. Stimulate consistent and productive exchange of ideas between clinicians and basic scientists while employing bench-to-bedside and bedside-to-bench strategies to generate and prioritize scientific questions. 3. Provide infrastructure and mentorship needed to successfully compete for external funding. 4. Engage the community through patient advocacy to positively impact brain cancer patient outcomes and enhance philanthropic initiatives. The Brain Tumor Working Group brings together scientists committed to engaging in a team-based approach to study GBM biology. Infrastructure required to advance in vivo humanized intracranial tumor models, drug delivery, target validation, and development of new therapeutic strategies are in place. Additionally a patient sample pipeline to obtain, analyze, and distribute primary patient GBM specimens from the operating room to the research laboratory has been established. In year one of funding, over $70,000 in pilot project funding derived from the Signature Center Initiative and private donations has been distributed to the membership. The Brain Tumor Working Group meets in both small and large group formats to strategize experimental design and grant submissions. A network of basic scientists and clinicians has been developed that provides an effective forum for addressing clinically relevant questions related to GBM. A team-based approach, scientific expertise, and continued development of infrastructure provide our membership with a critical foundation to obtain new knowledge related to understanding how GBM cells evade therapy. In the future, this information can be applied to development of effective treatments that will cure GBM