Surgical Approaches for Symptomatic Cerebral Cavernous Malformations of the Thalamus and Brainstem

Dale Ding,Robert M. Starke,R. Webster Crowley,Kenneth C. Liu 대한뇌혈관외과학회 2017 Journal of Cerebrovascular and Endovascular Neuros Vol.19 No.1

Objective:Surgical resection of thalamic and brainstem cerebral cavernous malformations (CCMs) is associated with significant operative morbidity, but it may be outweighed, in some cases, by the neurological damage from recurrent hemorrhage in these eloquent areas. The goals of this retrospective cohort study are to describe the technical nuances of surgical approaches and determine the postoperative outcomes for CCMs of the thalamus and brainstem. Materials and Methods:We reviewed an institutional database of patients harboring thalamic or brainstem CCMs, who underwent surgical resection from 2010 to 2014. The baseline and follow-up neuroimaging and clinical findings of each patient and the operative details of each case were evaluated. Results:A total of eight patients, including two with thalamic and six with brainstem CCMs, were included in the study cohort. All patients had progressive neurological deterioration from recurrent CCM hemorrhage, and the median modified Rankin Scale (mRS) at presentation was 3. The median CCM maximum diameter and volume were 1.7 cm and 1.8 cm3, respectively. The thalamic CCMs were resected using the anterior transcallosal transchoroidal and supracerebellar infratentorial approaches each in one case (13%). The brainstem CCMs were resected using the retrosigmoid and suboccipital trans-cerebellomedullary fissure approaches each in three cases (38%). After a median follow-up of 11.5 months, all patients were neurologically stable or improved, with a median mRS of 2. The rate of functional independence (mRS 0-2) was 63%. Conclusion : Microneurosurgical techniques and approaches can be safely and effectively employed for the management of thalamic and brainstem CCMs in appropriately selected patients.

Balloon Anchor Technique for Pipeline Embolization Device Deployment Across the Neck of a Giant Intracranial Aneurysm

Dale Ding,Robert M. Starke,Avery J. Evans,Mary E. Jensen,Kenneth C. Liu 대한뇌혈관외과학회 2014 Journal of Cerebrovascular and Endovascular Neuros Vol.16 No.2

Treatment of giant intracranial aneurysms, via either surgical or endovascularapproaches, is associated with a high level of technical difficulty aswell as a high rate of treatment-related morbidity and mortality. Flow-divertingstents, such as the Pipeline embolization device (PED), have drasticallyaltered the therapeutic strategies for the treatment of giant aneurysms. Gaining endovascular access using a microcatheter to the portion of theparent artery distal to the aneurysm neck is requisite for safe and effectivestent deployment. Giant aneurysms are often associated with vasculartortuosity, which necessitates significant catheter support systems to enablemaneuvering of PEDs across the aneurysm neck. This is also requiredin order to reduce the probability of stent herniation within giantaneurysms. We report on a case of a giant supraclinoid internal carotidartery (ICA) aneurysm which was treated successfully with a PED utilizinga balloon anchor technique to facilitate direct microcatheter access acrossthe aneurysm neck.

Microsurgical Strategies Following Failed Endovascular Treatment with the Pipeline Embolization Device: Case of a Giant Posterior Cerebral Artery Aneurysm

Dale Ding,Robert M. Starke,Kenneth C. Liu 대한뇌혈관외과학회 2014 Journal of Cerebrovascular and Endovascular Neuros Vol.16 No.1

Treatment of giant posterior circulation aneurysms, via endovascular or microsurgical approaches, carries a high risk of morbidity and mortality. While flow-diverting stents (FDSs) represent a potent therapy for endovascular reconstruction of complex aneurysms, they are also associated with novel complications for which effective salvage techniques are lacking. We present a unique complication from failed treatment with a FDS. A 51 year-old male presented with increasing headaches secondary to a giant, fusiform aneurysm of the left posterior cerebral artery, which was largely thrombosed. Due to progressive enlargement of the aneurysm corresponding to worsening clinical symptoms, the lesion was treated with two Pipeline embolization devices (ev3, Plymouth, MN, United States). Three months after Pipeline embolization device treatment, complete posterior cerebral artery occlusion was observed at the origin of the proximal stent. Despite the lack of arterial inflow, the aneurysm dome continued to grow, resulting in obstructive hydrocephalus. Therefore microsurgical intervention was undertaken to trap and excise the aneurysm. The patient's postoperative course was complicated by multiple venous infarcts, ultimately resulting in death. Successful microsurgical obliteration of aneurysms previously treated with FDSs is extremely difficult. A combination of judicious preoperative planning and meticulous intraoperative surgical technique are requisite for effective management of these complicated cases.

Eyebrow Incision for Surgical Evacuation of a Lobar Intracerebral Hematoma with a Novel Endoport System

Dale Ding,Colin J. Przybylowski,Robert M. Starke,R. Webster Crowley,Kenneth C. Liu 대한뇌혈관외과학회 2017 Journal of Cerebrovascular and Endovascular Neuros Vol.19 No.2

Large lobar intracerebral hemorrhages (ICHs) can cause rapid neurological deterioration, and affected patients have low rates of survival and functional independence. Currently, the role of surgical intervention in the management patients with lobar ICHs is controversial. Minimally invasive technologies have been developed which may potentially decrease the operative morbidity of ICH surgery. The aim of this case report is to describe the technical aspects of the use of a novel minimally invasive endoport system, the BrainPath (NICO, Indianapolis, IN, USA), through an eyebrow incision for evacuation of a large lobar hematoma. An 84-year-old female presented with a left frontal ICH, measuring 7.5 cm in maximal diameter and 81 cm3 in volume, secondary to cerebral amyloid angiopathy. Through a left eyebrow incision, a miniature modified orbitozygomatic craniotomy was performed, which allowed endoport cannulation of the hematoma from a lateral subfrontal cortical entry point. Endoport-assisted hematoma evacuation resulted in nearly 90% volume reduction and improvement of the patient's functional status at clinical follow-up. We found that minimally invasive endoport technology can be employed in conjunction with conventional neurosurgical skull base principles to achieve safe and effective evacuation of large lobar hematomas in carefully selected patients.

“Direct” Mechanical Thrombectomy in Acute Ischemic Stroke during Percutaneous Coronary Intervention

Vasu Saini,Marie-Christine Brunet,Samir Sur,Amer M. Malik,Priyank Khandelwal,Shashvat Desai,Robert M. Starke,Eric C. Peterson,Ashutosh P. Jadhav,Mauricio G. Cohen,Dileep R. Yavagal 대한뇌졸중학회 2020 Journal of stroke Vol.22 No.2

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Preoperative Embolization of Cerebral Arteriovenous Malformations with Silk Suture and Particles: Technical Considerations and Outcomes

Jordan R. Conger,Avery J. Evans,Dale Ding,Daniel M. Raper,Robert M. Starke,Christopher R. Durst,Kenneth C. Liu,Mary E. Jensen 대한뇌혈관외과학회 2016 Journal of Cerebrovascular and Endovascular Neuros Vol.18 No.2

Objective:Embolization of cerebral arteriovenous malformations (AVMs) is commonly performed prior to surgical resection in order to reduce intraoperative bleeding and improve the safety of resection. Although most modern embolization procedures utilize permanent embolic agents, silk suture and polyvinyl alcohol (PVA) particles may offer unique advantages for preoperative devascularization. The aims of this retrospective cohort study are to describe the technical considerations and determine the outcomes for preoperative silk suture and PVA particle embolization (SPE) of AVMs. Materials and Methods:We performed a retrospective review of our AVM embolization database. AVM patients who underwent preoperative SPE and subsequent surgical resection were included for analysis. Baseline patient demographics, AVM characteristics, embolization and operative records, and post-treatment outcomes were reviewed. Results:A total of 11 patients who underwent 12 preoperative SPE procedures were included for analysis. Five AVMs were ruptured (45%), and the median nidus volume was 3.0 cm3 (range: 1.3-42.9 cm3). The Spetzler-Martin grade was I-II in seven patients (64%) and III-IV in four patients (36%). The degree of nidal obliteration was less than 25% in two procedures (17%), 25-50% in one procedure (8%), 50-75% in eight procedures (67%), and greater than 75% in one procedure (8%). The rates of post-embolization AVM hemorrhage and mortality were 8% and 0%, respectively. The postoperative angiographic obliteration rate was 100%, and the modified Rankin Scale score improved or stable in 91% of patients (median follow-up duration 2 months). Conclusion:Preoperative AVM SPE affords a reasonable risk to benefit profile for appropriately selected patients.

TORSIONAL RESONANCE MODE ATOMIC FORCE MICROSCOPY OF A PROTEIN–DNA COMPLEX

GILBERTO WEISSMÜLLER,AYHAN YURTSEVER,LILIAN T. COSTA,ANA B. F. PACHECO,PAULO M. BISCH,WOLFGANG M. HECKL,ROBERT W. STARK 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2008 NANO Vol.3 No.6

Precise mapping of protein-binding sites on DNA is an important application of atomic force microscope (AFM) imaging. For a reliable measurement of distances on curved DNA molecules, an image-processing algorithm is required, which extracts the DNA contour from topographic AFM data. To this end we implemented an image analysis method providing an efficient way to obtain the contour together with a physical map of single and multiple protein-binding sites. This method relies on a calculation of the height profile along the DNA fragment, allowing one to determine the DNA length and the relative position of the binding site occupied by a protein. As a first test, complexes of the LexA repressor protein from the Escherichia coli SOS system and DNA fragments containing a specific LexA binding site (recA operator) were imaged by the torsional resonance mode (TR mode) and analyzed using the specialized algorithm. A topographic height of less than 0.5 nm of the DNA molecules indicates repulsive imaging conditions.