Frank P K Hsu

University of California, Irvine | UCI · Department of Neurological Surgery

INTRODUCTION: Surgery can be an effective treatment for epilepsy if the seizure onset is adequately localized. Invasive monitoring is used if noninvasive methods are inconclusive. Initial invasive monitoring may fail if the pre-surgical hypothesis regarding location of epileptic foci is wrong. At this point, a decision must be made whether to remov...

Introduction: Many epilepsy patients have medically refractory disease. Surgery can be effective if the seizure onset is adequately localized. Invasive monitoring is used if noninvasive methods are inconclusive. Invasive monitoring may fail if the pre-surgical hypothesis is wrong. In this case, a decision must be made whether to remove all electrod...

The results of our retrospective case series suggest that a second invasive monitoring surgery for implantation of additional SEEG or SDG can be safely performed in order to localize seizure foci and guide effective resection with favorable results.

Objectives/Hypothesis The objective of this study is to evaluate the impact of patient and surgical factors, including approach and reconstruction type, on postoperative nausea and vomiting episodes following endoscopic skull base surgery. Study Design Retrospective review. Methods We performed a retrospective chart review from July 2018 to Augus...

Objective Pituitary adenomas in the pediatric population are extremely rare, resulting in limited information in the literature on these patients. In this study, data from the National Cancer Database (NCDB) to compare pituitary adenoma clinical presentations, treatment management patterns, and overall survival between pediatric and adult patients....

Background Chronic subdural hematoma (cSDH) is predicted to become the most common intracranial neurosurgical condition by 2030. Recurrence is estimated between 5-15%, and the use of a surgical drain is associated with lower recurrence rates. The authors present their experience with six patients undergoing cSDH evacuation with an irrigating draina...

Objective With the advent of minimally invasive techniques, minimally invasive spine surgery (MISS) has become a realistic option for many spine cases. This study aims to evaluate the operative and clinical outcomes of MISS for total versus subtotal tumor resection from current evidence. Methods A literature search was performed using the search t...

Introduction: There are currently no large-sample studies assessing the clinical outcomes of pituitary adenomas (PA) patients undergoing active surveillance (AS) versus definitive treatment (DT). This population-based analysis aims to identify clinical and sociodemographic predictors of undergoing AS and compare clinical outcomes of PA patients und...

Introduction: There remain controversies regarding whether elderly patients are predisposed to more complications following pituitary adenoma (PA) surgical resection. This study utilizes a large-population national database to compare clinical outcomes between young and elderly patients receiving either endoscopic surgery (ES) or nonendoscopic surg...

A retrospective review identified all patients undergoing endoscopic skull base surgery at a tertiary academic skull base surgery program. 104 patients from July 2018 through August 2020 who underwent endoscopic skull base surgery were identified. Those with LD placement for aiding in suprasellar dissection and/or for CSF diversion following skull...

Moyamoya is a rare, steno-occlusive cerebrovascular disorder that often presents as ischemic or hemorrhagic intracerebral events. This review provides an overview of various surgical revascularization techniques used in treating Moyamoya disease including direct, indirect, and combined revascularization, as well as the benefits, drawbacks, and indi...

GBM standard treatment is associated with poor survival. Adjunctive therapy with patient-specific vaccines may improve outcomes by enhancing anti-GBM immune responses. A multi-institutional phase II clinical trial was designed with a primary objective of 75% survival 15 months after intent-to-treat enrollment. IL-4 and GM-CSF were used to generate...

ERC1671 is an allogeneic/autologous therapeutic vaccine – composed of whole, inactivated tumor cells mixed with tumor- cell lysates. The hypothesized action of ERC1671 is to potentiate the patients’ immune system against the tumor. Goals of this ongoing, phase 2 study are to determine the safety and effectiveness (overall survival) of ERC1671 in co...

Background Primary glioblastoma (GBM) is associated with poor survival. Adjunctive vaccines may improve survival by inducing or enhancing anti-GBM immune responses. Methods A multi-institutional phase II clinical trial was conducted with a primary objective of 75% survival 15 months after intent-to-treat enrollment. Key eligibility criteria were:...

Objective Single neuron or unit recording enables researchers to measure the electrophysiologic responses of single neurons using a microelectrode system. This approach is widely used in cognitive science and has become more widespread in humans with the use of hybrid (micro-within-macrowire) depth electrodes that enable the implantation of microwi...

Few centers have routinely implemented robotic stereotactic systems for deep brain stimulator (DBS) placement. The present study compares clinical outcomes associated with robotic-assisted subthalamic nucleus (STN)-targeted DBS surgery in patients with Parkinson’s disease (PD) to those of the traditional frame-based method. A retrospective chart re...

Objective The influence of graft type (non-autologous versus autologous) on surgical outcomes in endoscopic anterior skull base (EASB) reconstruction is not well-understood. This review systematically evaluated rates of post-operative complications of EASB repairs that utilized autologous or non-autologous grafts. Methods Original studies reportin...

BACKGROUND The responsive neurostimulation system (RNS) (NeuroPace Inc, Mountain View, California) was approved as an adjunctive therapy for medically refractory focal epilepsy. RNS detects epileptiform patterns and delivers electrical stimulation to abort seizures. OBJECTIVE To describe a novel technique of RNS lead implantation using robotic-ass...

Background: Pituitary apoplexy (PA) can manifest with visual and endocrine defects. The literature lacks strong support for either surgical or conservative management with respect to symptomatic improvement of these deficits. This meta-analysis compared visual and endocrine outcomes in conservative and surgical treatment of PA. Methods: A system...

Background: Esthesioneuroblastoma (ENB), also known as olfactory neuroblastoma, represents up to 3% of all sinonasal neoplasms. Hyams histologic grading is a promising tool in predicting metastases and establishing prognoses for this complex tumor. Methods: A systematic literature search was performed in the PubMed, Ovid MEDLINE, and Cochrane da...

How do we remember emotional events? While emotion often leads to vivid recollection, the precision of emotional memories can be degraded, especially when discriminating among overlapping experiences in memory (i.e., pattern separation). Communication between the amygdala and the hippocampus has been proposed to support emotional memory, but the ex...

Background: Hemispherectomy is a successful and well-described treatment option for pediatric patients with hemispheric ictal onset, but adult outcomes have been far less studied. We describe the outcomes in adult patients with medically refractory epilepsy and hemispheric disease and the relationship to cerebral peduncle volume. Case description...

BACKGROUND ERC1671 is an allogeneic/autologous therapeutic glioblastoma (GBM) vaccine composed of whole, inactivated tumor cells mixed with tumor cell lysates derived from the patient and three GBM donors. Previously published compassionate use data showed an overall survival (OS) of 43 weeks (10 months) in patients with a good performance status....

Objective: To describe neurosurgical patient and caregiver perceptions of provider communication, the impact of patient education, and their understanding of information given to them throughout the neurosurgical care trajectory. Methods: We organized focus groups comprised of patients and caregivers who had been hospitalized on the neurosurgica...

Background: Multiple intracranial meningiomas account for <10% of all meningiomas. Familial multiple meningiomas have been linked to germline mutations in two genes: neurofibromatosis type 2 (NF2) and SWIch/Sucrose Non-Fermentable (SWI/SNF)-related matrix-associated actin-dependent regulator of chromatin subfamily B member 1 (SMARCB1). Sporadic mul...

Glioblastoma is the most common form of brain cancer in adults that produces severe damage to the brain leading to a very poor survival prognosis. The standard of care for glioblastoma is usually surgery, as well as radiotherapy followed by systemic temozolomide chemotherapy, resulting in a median survival time of about 12 to 15 months. Despite the...

OBJECTIVE Surgical treatment of patients with medically refractory focal epilepsy is underutilized. Patients may lack access to surgically proficient centers. The University of California, Irvine (UCI) entered strategic partnerships with 2 epilepsy centers with limited surgical capabilities. A formal memorandum of understanding (MOU) was created to...

Background: Neurosurgery inpatients are oftentimes critically ill, and face significant stress, post-operative pain, and/or emotional distress. As a result, the use of non-pharmacologic, alternative therapies as adjuncts in surgical care may benefit this patient population. Hospital economics related to integrative services may also provide additi...

Myeloid sarcoma, a rare consequence of myeloproliferative disorders, is rarely seen in the central nervous system, most commonly in the pediatric population. Although there are a handful of case reports detailing initial presentation of CNS myeloid sarcoma in the adult population, we have been unable to find any reports of CNS myeloid sarcoma prese...

INTRODUCTION Neurosurgery inpatients are oftentimes critically ill and are admitted for a variety of pathologies. They face significant stress, post-operative pain, and/or emotional distress due to their underlying condition. As a result, decreased patient satisfaction, increased post-surgical pain, and increased hospital stays are not uncommon. Th...

Epilepsy surgery is indicated in select patients with drug-resistant focal epilepsy. Seizure freedom or significant reduction of seizure burden without risking new neurological deficits is the expected goal of epilepsy surgery. Typically, when the seizure onset zone overlaps with eloquent cortex, patients are excluded from surgery. We present a pat...

BACKGROUND:Responsive neurostimulation (RNS) is a relatively new treatment option that has been shown to be effective for patients with medically refractory focal epilepsy when resection is not possible, especially in bilateral mesial temporal onset. Robotic devices are becoming increasingly popular for use in stereotactic procedures such as stereo...

Objective: Lowering the length of stay (LOS) is thought to potentially decrease hospital costs and is a metric commonly used to manage capacity. Patients with epilepsy undergoing intracranial electrode monitoring may have longer LOS because the time to seizure is difficult to predict or control. This study investigates the effect of economic impli...

Recognizing motivationally salient information is critical to guiding behaviour. The amygdala and hippocampus are thought to support this operation, but the circuit-level mechanism of this interaction is unclear. We used direct recordings in the amygdala and hippocampus from human epilepsy patients to examine oscillatory activity during processing...

Supplementary Figures and Supplementary Table.

Background: Aneurysmal subarachnoid hemorrhages are frequently complicated by hypertension and neurogenic myocardial stunning. Betablockers may be used for management of these complications. We sought to investigate sympathetic nervous system modulation by beta blockers and their effect on radiographic vasospasm, delayed cerebral infarction, discha...

Laser interstitial thermal therapy (LITT) is a minimally invasive procedure used to treat a variety of intracranial lesions. Utilization of robotic assistance with stereotactic procedures has gained attention due to potential for advantages over conventional techniques. The authors report the first case in which robot-assisted MRI-guided LITT was u...

Background: Classically, transoccipital hippocampal depth electrode implantation requires a stereotactic headframe and arc and the patient to be placed in a seated or prone position, which can be cumbersome to position and uncomfortable for the surgeon. Robotic intracranial devices are increasingly being utilized for stereotactic procedures such as...

Introduction: Stereoelectroencephalography (SEEG) and subdural grids (SDG) are both effective options for localizing the ictal onset zone in patients with frequent seizures. The choice of intracranial monitoring technique utilized depends upon several factors, including the patient's clinical presentation and history. This article addresses a rare...

Objective: Electrocorticography (ECoG)-based brain-computer interface (BCI) is a promising platform for controlling arm prostheses. To restore functional independence, a BCI must be able to control arm prostheses along at least six degrees-of-freedoms (DOFs). Prior studies suggest that standard ECoG grids may be insufficient to decode multi-DOF ar...

Background: Electrode implantation for Deep Brain Stimulation (DBS) can be performed in numerous ways, but the current "gold standard" utilizes frame-based systems for accuracy. However, robotic stereotactic procedures have gained increased interest due to their ease of use and reliability, but there could be concern about their safety in the Unit...

Malignant gliomas continue to have a dismal prognosis despite all available treatments and advances made in understanding molecular mechanisms and signaling pathways. Conventional treatments, such as surgery, chemotherapy and radiation, have been used with limited success. Bevacizumab is a recently described molecule, which inhibits endothelial pro...

Glioblastoma Multiforme (GBM) is the most common type of brain tumor and it is uniformly fatal. The community standard of treatment for this disease is gross or subtotal resection of the tumor, followed by radiation and temozolomide. At recurrence bevacizumab can be added for increased progression free survival. Many challenges are encountered whil...

Object: Deep brain stimulation (DBS) for dystonic cerebral palsy (CP) has rarely been reported, and its efficacy, though modest when compared with that for primary dystonia, remains unclear, especially in the pediatric population. The authors present a small series of children with dystonic CP who underwent bilateral pallidal DBS, to evaluate the...

Glioblastoma Multiforme (GMB) is the most aggressive primary brain tumor with poor survival rates and universal recurrence despite aggressive treatments. Recent research suggested that GBM has multiple glioma cell populations, some of which are organized in a stem cell hierarchical order with different stages of differention. Evidence indicated tha...

Electrocorticogram (ECoG)-based brain computer interfaces (BCI) can potentially control upper extremity prostheses to restore independent function to paralyzed individuals. However, current research is mostly restricted to the offline decoding of finger or 2D arm movement trajectories, and these results are modest. This study seeks to improve the f...

Despite recent advances in the treatment of malignant gliomas (World Health Organization grade III and grade IV tumors- Glioblastoma Multiforme, Anaplastic Astrocytoma and Anaplastic Oligodendroglioma), the overall prognosis remains poor. Tumor recurrence in malignant glioma is inevitable, and associated with reduced overall survival (OS). Bevacizu...

Despite aggressive investigation, glioblastoma multiforme (GBM) remains one of the deadliest cancers, with low progression-free survival and high one-year mortality. Current first-line therapy includes surgery with adjuvant radiation therapy and cytotoxic chemotherapy, but virtually all tumors recur. Given the highly vascular nature of GBM and its...

Electrocorticogram (ECoG)-based brain computer interfaces (BCI) can potentially control upper extremity pros-theses to restore independent function to paralyzed individuals. However, current research is mostly restricted to the offline decoding of finger or 2D arm movement trajectories, and these results are modest. This study seeks to improve the...

Electrocorticography has been widely explored as a long-term signal acquisition platform for brain-computer interface (BCI) control of upper extremity prostheses. However, a comprehensive study of elementary upper extremity movements and their relationship to electrocorticogram (ECoG) signals has yet to be performed. This study examines whether kin...

Electrocorticogram (ECoG)-based brain computer interfaces (BCI) can potentially be used for control of arm prostheses. Restoring independent function to BCI users with such a system will likely require control of many degrees-of-freedom (DOF). However, our ability to decode many-DOF arm movements from ECoG signals has not been thoroughly tested. To...

Subjects undergoing subdural electrode placement for epilepsy evaluation performed a series of six elementary upper extremity movements. Depending on grid location, the electrocorticographic (ECoG) signals in the high gamma band were found to encode the velocity of these movements. To the best of our knowledge, this represents the first comprehensi...

Object: This study was designed to determine if the "keyhole concept," proposed by Perneczky's group, can be verified quantitatively. Methods: Fourteen (3 bilateral and 8 unilateral) sides of embalmed latex-injected cadaveric heads were dissected via 3 sequential craniotomy approaches: supraorbital keyhole, frontotemporal pterional, and supraorb...

To evaluate the efficacy of fractionated proton radiotherapy for a population of patients with benign cavernous sinus meningiomas. Between 1991 and 2002, 72 patients were treated at Loma Linda University Medical Center with proton therapy for cavernous sinus meningiomas. Fifty-one patients had biopsy or subtotal resection; 47 had World Health Organ...

Neurosurgical operations cause unavoidable damage to healthy brain tissues. Direct surgical injury as well as surgically induced oxidative stress contributes to the subsequent formation of brain edema. Therefore, we tested the neuroprotective effects of hydrogen (H2) in an established surgical brain injury (SBI) model in rats. Adult male Sprague -...

Spinal cord herniation through a dural defect is a cause of myelopathy and BSS that may be underdiagnosed. It may occur spontaneously, after trauma, or after surgery. We present the case of a 47-year-old woman who presented with low back pain, progressive myelopathy, right proximal LEW, several episodes of falling, sensory changes below the lower p...