The Ultimate Skull Base Maneuver Does Not Involve Removing Bone: Quantifying the Benefits of the Interfascial Dissection.

Introduction Several adjunctive osteal skull base maneuvers have been proposed to increase surgical exposure of the anterolateral approach. However, one of the easiest methods does not involve bone: the interfascial temporalis muscle dissection. Methods Sequential dissections were performed bilaterally on five fixed silicone-injected cadaver heads. The amount of sphenoid drilling, scalp retraction, and brain retraction was standardized in all specimens. For each approach, surgical angles were measured for four deep targets: the tip of the anterior clinoid process, the internal carotid artery terminus, the origin of the posterior communicating artery, and the anterior communicating artery. Five surgical angles were measured for each target. Results There were increases on the order of 20% in the anteroposterior (AP)-mid, AP-lateral, and mediolateral-anterior angles for all deep targets with interfascial approach versus a myocutaneous flap. An orbitozygomatic osteotomy additionally increased almost all the angles, but incrementally less so. Conclusion An interfascial dissection increases the surgical exposure to a larger degree than additional osteotomies for several surgically relevant working angles. The addition of an orbitozygomatic osteotomy affords a particular benefit for the suprachiasmatic region. Increased adoption of interfascial mobilization or the temporalis muscle-an easily performed and low-risk maneuver-during anterolateral craniotomies may obviate the need for more involved skull base drilling.

Republished: Revisiting the therapeutic time window dogma: successful thrombectomy 6 days after stroke onset.

Stroke is the leading cause of serious long-term disability in the USA. Recent clinical trials, DAWN and DEFUSE 3, have expanded the endovascular therapeutic time window which has been adopted by the American Heart Association stroke guideline. However, there continues to be a dilemma as to what is the best approach for patients who present beyond the time window set by these trials and the current guideline. The interval from arterial occlusion to completion of brain tissue infarction varies from patient to patient and depends on the actual time and also a physiological clock or a tissue time window. Offering endovascular treatment based solely on a rigid time criterion excludes patients who may have a clinical benefit because of potentially salvageable tissue. We present a case of a patient who underwent successful stroke thrombectomy 6 days after stroke onset.

Revisiting the therapeutic time window dogma: successful thrombectomy 6 days after stroke onset.

Stroke is the leading cause of serious long-term disability in the USA. Recent clinical trials, DAWN and DEFUSE 3, have expanded the endovascular therapeutic time window which has been adopted by the American Heart Association stroke guideline. However, there continues to be a dilemma as to what is the best approach for patients who present beyond the time window set by these trials and the current guideline. The interval from arterial occlusion to completion of brain tissue infarction varies from patient to patient and depends on the actual time and also a physiological clock or a tissue time window. Offering endovascular treatment based solely on a rigid time criterion excludes patients who may have a clinical benefit because of potentially salvageable tissue. We present a case of a patient who underwent successful stroke thrombectomy 6 days after stroke onset.

Fast acquisition cone-beam computed tomography: initial experience with a 10 s protocol.

BACKGROUND: Cone-beam computed tomography (CBCT) facilitates the acquisition of cross-sectional imaging in angiography suites using a rotational C-arm and digital flat panel detectors. The applications are numerous, including evaluation of implanted devices and localization of cerebrovascular lesions. We present and validate the clinical utility of an alternative fast CBCT acquisition protocol in the context of neurovascular device imaging. METHODS: Contrast-enhanced (CE)-CBCT images were acquired using a new 10 s protocol in a phantom head model, swine model, and in patients. The acquisition parameters of both the 10 s and 20 s protocols were exactly the same, except for fewer projections (250 projections in 10 s vs 500 projections in 20 s), resulting in reduced scan time. Image quality was measured quantitatively in a controlled phantom study and qualitatively by blinded reviewers. The latter was performed to assess the image quality of the 10 s protocol pertinent to the device visibility and its apposition to the parent artery. RESULTS: 10 s CBCT images were comparable to 20 s CBCT in both phantom and animal studies. Of the 25 patient images, the reviewers agreed that they were able to discern the flow diverter struts and assess the apposition in all images. The overall rating for all 10 s images was 4.28 on a 5-point scale. No images were rated as less than 3, which was the average diagnostic quality. The ratings were concordant across three blinded reviewers (κ=0.411). Additionally, contrast and spatial resolution between 10 s and 20 s images were similar in non-human models. CONCLUSIONS: CBCT images of neurovascular devices can be obtained successfully using a 10 s acquisition protocol. In addition, the 10 s protocol offers faster acquisition, thus allowing its use in awake patients and with an added advantage of lower radiation and contrast dose.

The 1-piece transbasal approach: operative technique and anatomical study.

OBJECT: The transbasal approach (TBA) is an anterior skull base approach, which provides access to the anterior skull base, sellar-suprasellar region, and clivus. The TBA typically involves a bifrontal craniotomy with orbital bar and/or nasal bone osteotomies performed in 2 separate steps. The authors explored the feasibility of routinely performing this approach in 1 piece with a quantitative cadaveric anatomical study, and present an operative case example of their approach. METHODS: Seven latex-injected cadaveric heads underwent a 1-piece TBA, followed by additional bone removal typical for a traditional 2-piece approach. Six surgical angles relative to the pituitary stalk, as well as the surface area of the orbital roof osteotomy, were measured before and after additional bone removal. The vertical angle from the frontonasal suture to the foramen cecum was measured in all specimens. In addition to an anatomical study, the authors have used this technique in the operating room, and present an illustrative case of resection of an anterior skull base meningioma. RESULTS: Morphometric results were as follows: the vertical angle from the frontonasal suture to the foramen cecum ranged from 17.4° to 29.7° (mean 23.8° ± 4.8°) superiorly. Of the 6 surgical angle measures, only the middle horizontal angle was increased in the 2-piece versus the 1-piece approach (mean 43.4° ± 4.6° vs 43.0° ± 4.3°, respectively; p = 0.049), with a mean increase of 0.4°. The surface area of the orbital osteotomy was increased in the 2-piece versus the 1-piece approach (mean 2467 mm(2) ± 360 mm(2) vs 2045 mm(2) ± 352 mm(2), respectively; p < 0.001). The patient in the illustrative clinical case had a good outcome, both clinically and cosmetically. CONCLUSIONS: The 1-piece TBA provides an alternative to the traditional 2-piece approach. It allows easier reconstruction, potentially decreased operative time, and improved cosmesis. While more of the orbital roof can be removed with the 2-piece approach, this additional bone removal offers only a small increase in 1 of 6 surgical angles that were measured.

A review of the neurological and neurosurgical implications of tuberculosis in children.

Tuberculous involvement of the central nervous system (CNS) and vertebral column is the most lethal and disabling form of tuberculosis (TB). Several factors contribute to poor outcome, including cerebrovascular involvement with ischemia, hydrocephalus, direct parenchymal injury and formation of abscess and inflammation in the brain and spinal cord, hyponatremia, seizures, and delayed diagnosis. Spinal spondylitis from TB and associated spinal deformity is the leading cause of paraplegia in developing countries. The evidence for supportive treatment of TB infection of the CNS is limited, leading to substantial differences in management protocols. Many of the treatment approaches used in TB infection of the CNS have been extrapolated from treatment of other acute neurological disorders such as bacterial meningitis and traumatic brain injury. We review data from the available literature and highlight questions relating to the neurological and neurosurgical care of children with TB infection of the CNS and vertebral column.