Search Results

You are looking at 1 - 10 of 17 items for

  • Author or Editor: H. Isaac Chen x
Clear All Modify Search
Full access

H. Isaac Chen, Leif-Erik Bohman, Laurie A. Loevner and Timothy H. Lucas

Object

Resection of the hippocampus is the standard of care for medically intractable epilepsy in patients with mesial temporal sclerosis. Although temporal craniotomy in this setting is highly successful, the procedure carries certain immutable risks and may be associated with cognitive deficits related to cortical and white matter disruption. Alternative surgical approaches may reduce some of these risks by preserving the lateral temporal lobe. This study examined the feasibility of transorbital endoscopic amygdalohippocampectomy (TEA) as an alternative to open craniotomy in cadaveric specimens.

Methods

TEA dissections were performed in 4 hemispheres from 2 injected cadaveric specimens fixed in alcohol. Quantitative predictions of the limits of exposure based on predissection imaging were compared with intradissection measurements. The extent of resection and angles of exposure during the dissection and on postdissection imaging were recorded. These measurements were validated with MRI studies from 10 epilepsy patients undergoing standard surgical evaluations.

Results

The transorbital approach permitted direct access to the mesial temporal structures through the lateral orbital wall. Up to 97% of the hippocampal formation was resected with no brain retraction and minimal (mean 6.0 ± 1.4 mm) globe displacement. Lateral temporal lobe white matter tracts were preserved.

Conclusions

TEA permits hippocampectomy comparable to standard surgical approaches without disrupting the lateral temporal cortex or white matter. This novel approach is feasible in cadaveric specimens and warrants clinical investigation in carefully selected cases.

Restricted access

Andrew I. Yang, Brendan J. McShane, Frederick L. Hitti, Sukhmeet K. Sandhu, H. Isaac Chen and John Y. K. Lee

OBJECTIVE

First-line treatment for trigeminal neuralgia (TN) is pharmacological management using antiepileptic drugs (AEDs), e.g., carbamazepine (CBZ) and oxcarbazepine (OCBZ). Surgical intervention has been shown to be an effective and durable treatment for TN that is refractory to medical therapy. Despite the lack of evidence for efficacy in patients with TN, the authors hypothesized that patients with neuropathic facial pain are prescribed opioids at high rates, and that neurosurgical intervention may lead to a reduction in opioid use.

METHODS

This is a retrospective study of patients with facial pain seen by a single neurosurgeon. All patients completed a survey on pain medications, medical comorbidities, prior interventions for facial pain, and a validated pain outcome tool (the Penn Facial Pain Scale). Patients subsequently undergoing neurosurgical intervention completed a survey at the 1-month follow-up in the office, in addition to telephone interviews using a standardized script between 1 and 6 years after intervention. Univariate and multivariate logistic regression were used to predict opioid use.

RESULTS

The study cohort consisted of 309 patients (70% Burchiel type 1 TN [TN1], 18% Burchiel type 2 [TN2], 6% atypical facial pain [AFP], and 6% TN secondary to multiple sclerosis [TN-MS]). At initial presentation, 20% of patients were taking opioids. Of these patients, 55% were receiving concurrent opioid therapy with CBZ/OCBZ, and 84% were receiving concurrent therapy with at least one type of AED. Facial pain diagnosis (for diagnoses other than TN1, odds ratio [OR] 2.5, p = 0.01) and facial pain intensity at its worst (for each unit increase, OR 1.4, p = 0.005) were predictors of opioid use at baseline. Neurosurgical intervention led to a reduction in opioid use to 8% at long-term follow-up (p < 0.01, Fisher’s exact test; n = 154). Diagnosis (for diagnoses other than TN1, OR 4.7, p = 0.002) and postintervention reduction in pain at its worst (for each unit reduction, OR 0.8, p < 10−3) were predictors of opioid use at long-term follow-up. On subgroup analysis, patients with TN1 demonstrated a decrease in opioid use to 5% at long-term follow-up (p < 0.05, Fisher’s exact test), whereas patients with non-TN1 facial pain did not. In the nonsurgical group, there was no statistically significant decrease in opioid use at long-term follow-up (n = 81).

CONCLUSIONS

In spite of its high potential for abuse, opioid use, mostly as an adjunct to AEDs, is prevalent in patients with facial pain. Opportunities to curb opioid use in TN1 include earlier neurosurgical intervention.

Restricted access

H. Isaac Chen, Gregory G. Heuer, Kareem Zaghloul, Scott L. Simon, John B. Weigele and M. Sean Grady

✓Vertebral hemangiomas are common entities that rarely present with neurological deficits. The authors report the unusual case of a large L-3 vertebral hemangioma with epidural extension in a 27-year-old woman who presented with hip flexor and quadriceps weakness, foot drop, and leg pain. The characteristics of the mass on magnetic resonance imaging suggested an aggressive, hypervascular lesion. The patient underwent embolization of the lesion followed by direct intralesional injection of ethanol. Significant resolution of clinical symptoms was observed immediately after the procedure and at her follow-up visits. Follow-up imaging studies obtained 9 months after the procedure also documented a considerable reduction in the size of the hemangioma with minimal loss of vertebral height and a mild kyphosis at the affected level. On repeated imaging studies obtained 21 months postoperatively, the size of the hemangioma and the degree of vertebral body compression were stable. As demonstrated in this case, patients with vertebral hemangiomas can present with acute nerve root compression and signs and symptoms similar to those of disc herniation. Vertebral hemangiomas can be treated effectively with interventional techniques such as embolization and ethanol injection.

Restricted access

H. Isaac Chen, Mark G. Burnett, Jason T. Huse, Robert A. Lustig, Linda J. Bagley and Eric L. Zager

✓Late cerebral radiation necrosis usually occurs within 3 years of stereotactic radiosurgery. The authors report on a case of recurrent radiation necrosis with rapid clinical deterioration and imaging findings resembling those of a malignant glioma. This 68-year-old man, who had a history of a left posterior temporal and thalamic arteriovenous malformation (AVM) treated with linear accelerator radiosurgery 13 years before presentation and complicated by radiation necrosis 11 years before presentation, exhibited new-onset mixed aphasia, right hemiparesis, and right hemineglect. Imaging studies demonstrated hemorrhage and an enlarging, heterogeneously enhancing mass in the region of the previously treated AVM. The patient was treated medically with corticosteroid agents, and stabilized temporarily. Unfortunately, his condition worsened precipitously soon thereafter, requiring the placement of a shunt for relief of obstructive hydrocephalus. Further surgical intervention was offered, but the patient’s family opted for hospice care instead. The patient died 10 weeks after initially presenting to the authors’ institution, and the results of an autopsy demonstrated radiation necrosis.

Symptomatic radiation necrosis can occur more than a decade after stereotactic radiosurgery, necessitating patient follow up during a longer period of time than currently practiced. Furthermore, there is a need for more careful reporting on the natural history of such cases to clarify the pathogenesis of very late and recurrent radiation necrosis after radiosurgery and to define patient groups with a higher risk for these entities.

Restricted access

Suresh N. Magge, H. Isaac Chen, Greg G. Heuer, Lee R. Carrasco, Phillip B. Storm and M.D.

✓Dislocation of the mandibular condyle into the middle cranial fossa is a rare event due to anatomical and biome chanical factors. The authors report the case of a 12-year-old girl who presented with this condition after colliding with a classmate. One day after her injury, the patient demonstrated an inability to close her mouth completely, and she had minor tenderness to palpation anterior to the tragus, without neurological deficits. Imaging studies demonstrated a frac tured glenoid fossa with intrusion of the mandible into the cranial cavity. Open reduction of the mandibular condyle was performed, and the glenoid fossa was reconstructed with a split-thickness bone graft and titanium screws. Several dural tears noted at the time of surgery were repaired primarily.

Mandibular condyle dislocation into the middle cranial fossa is often misdiagnosed initially because of its low inci dence and nonspecific symptoms. Computed tomography scanning is the most sensitive diagnostic study for detecting this injury. Closed reduction after induction of general anesthesia has been recommended in recently suffered injuries without neurological deficits, but this approach may overlook damage to intracranial structures. Surgical repair is rec ommended if neurological injury is suspected. Treatment options should be tailored to the individual factors of each case.

Restricted access

Suresh N. Magge, H. Isaac Chen, Rohan Ramakrishna, Liyi Cen, Zhen Chen, J. Paul Elliott, H. Richard Winn and Peter D. Le Roux

Object

Vasospasm is a leading cause of morbidity and death following aneurysmal subarachnoid hemorrhage (SAH). It is important to predict which patients are at risk for vasospasm so that interventions can be made. There are several potential risk factors for vasospasm, one of which is age. However, the effect of age on vasospasm, particularly symptomatic vasospasm, remains controversial.

Methods

Three hundred ninety-one patients were retrospectively identified from a prospective observational database of patients with SAH who had been admitted to a single center. Demographic and clinical data were recorded, and cerebral angiograms obtained at admission and between 5 and 10 days later were compared. The relationship between age and angiographic and symptomatic vasospasms was examined using logistic regression techniques.

Results

Mild (86 patients), moderate (69 patients), severe (56 patients), and no angiographic vasospasms (180 patients) were documented by comparing admission and follow-up angiograms in each patient. Symptomatic vasospasm was identified in 69 patients (17.6%). Angiographic vasospasm was more frequent as age decreased. Except in patients < 30 years old, the frequency of symptomatic vasospasm also increased with decreasing age (p = 0.0001). After adjusting for variables known to be associated with vasospasm, an advanced age was associated with a reduced incidence of any angiographic vasospasm (OR 0.96, 95% CI 0.94–0.97), severe angiographic vasospasm (OR 0.96, 95% CI 0.95–0.98), and symptomatic vasospasm (OR 0.98, 95% CI 0.96–0.99).

Conclusions

Results in this study show that a younger age is associated with an increased incidence of angiographic and symptomatic vasospasm.

Full access

Jared M. Pisapia, Nikhil R. Nayak, Ryan D. Salinas, Luke Macyszyn, John Y. K. Lee, Timothy H. Lucas, Neil R. Malhotra, H. Isaac Chen and James M. Schuster

OBJECTIVE

As odontoid process fractures become increasingly common in the aging population, a technical understanding of treatment approaches is critical. 3D image guidance can improve the safety of posterior cervical hardware placement, but few studies have explored its utility in anterior approaches. The authors present in a stepwise fashion the technique of odontoid screw placement using the Medtronic O-arm navigation system and describe their initial institutional experience with this surgical approach.

METHODS

The authors retrospectively reviewed all cases of anterior odontoid screw fixation for Type II fractures at an academic medical center between 2006 and 2015. Patients were identified from a prospectively collected institutional database of patients who had suffered spine trauma. A standardized protocol for navigated odontoid screw placement was generated from the collective experience at the authors' institution. Secondarily, the authors compared collected variables, including presenting symptoms, injury mechanism, surgical complications, blood loss, operative time, radiographically demonstrated nonunion rate, and clinical outcome at most recent follow-up, between navigated and nonnavigated cases.

RESULTS

Ten patients (three female; mean age 61) underwent odontoid screw placement. Most patients presented with neck pain without a neurological deficit after a fall. O-arm navigation was used in 8 patients. An acute neck hematoma and screw retraction, each requiring surgery, occurred in 2 patients in whom navigation was used. Partial vocal cord paralysis occurred after surgery in one patient in whom no navigation was used. There was no difference in blood loss or operative time with or without navigation. One patient from each group had radiographic nonunion. No patient reported a worsening of symptoms at follow-up (mean duration 9 months).

CONCLUSIONS

The authors provide a detailed step-by-step guide to the navigated placement of an odontoid screw. Their surgical experience suggests that O-arm–assisted odontoid screw fixation is a viable approach. Future studies will be needed to rigorously compare the accuracy and efficiency of navigated versus nonnavigated odontoid screw placement.

Restricted access

Ian F. Caplan, Gregory Glauser, Stephen Goodrich, H. Isaac Chen, Timothy H. Lucas, John Y. K. Lee, Scott D. McClintock and Neil R. Malhotra

OBJECTIVE

Obstructive sleep apnea (OSA) is known to be associated with negative outcomes and is underdiagnosed. The STOP-Bang questionnaire is a screening tool for OSA that has been validated in both medical and surgical populations. Given that readmission after surgical intervention is an undesirable event, the authors sought to investigate, among patients not previously diagnosed with OSA, the capacity of the STOP-Bang questionnaire to predict 30-day readmissions following craniotomy for a supratentorial neoplasm.

METHODS

For patients undergoing craniotomy for treatment of a supratentorial neoplasm within a multiple-hospital academic medical center, data were captured in a prospective manner via the Neurosurgery Quality Improvement Initiative (NQII) EpiLog tool. Data were collected over a 1-year period for all supratentorial craniotomy cases. An additional criterion for study inclusion was that the patient was alive at 30 postoperative days. Statistical analysis consisted of simple logistic regression, which assessed the ability of the STOP-Bang questionnaire and additional variables to effectively predict outcomes such as 30-day readmission, 30-day emergency department (ED) visit, and 30-day reoperation. The C-statistic was used to represent the receiver operating characteristic (ROC) curve, which analyzes the discrimination of a variable or model.

RESULTS

Included in the sample were all admissions for supratentorial neoplasms treated with craniotomy (352 patients), 49.72% (n = 175) of which were female. The average STOP-Bang score was 1.91 ± 1.22 (range 0–7). A 1-unit higher STOP-Bang score accurately predicted 30-day readmissions (OR 1.31, p = 0.017) and 30-day ED visits (OR 1.36, p = 0.016) with fair accuracy as confirmed by the ROC curve (C-statistic 0.60–0.61). The STOP-Bang questionnaire did not correlate with 30-day reoperation (p = 0.805) or home discharge (p = 0.315).

CONCLUSIONS

The results of this study suggest that undiagnosed OSA, as assessed via the STOP-Bang questionnaire, is a significant predictor of patient health status and readmission risk in the brain tumor craniotomy population. Further investigations should be undertaken to apply this prediction tool in order to enhance postoperative patient care to reduce the need for unplanned readmissions.

Restricted access

Suresh N. Magge, H. Isaac Chen, Michael F. Stiefel, Linda Ernst, Ann Marie Cahill, Robert Hurst and Phillip B. Storm

✓The authors report the case of an 18-month-old girl who presented with a ruptured anterior communicating artery aneurysm, and who was later diagnosed with Takayasu arteritis. Her initial aneurysm was successfully treated with clip application. However, over a 6-month period she had multiple ruptures from new and rapidly recurring aneurysms adjacent to the clips. These aneurysms were treated with repeated craniotomy and clip application and then with endovascular coil placement. Aneurysmal subarachnoid hemorrhage is a rare presentation of Takayasu arteritis. To the authors' knowledge, this is the youngest reported patient with Takayasu arteritis to present with a ruptured cerebral aneurysm.

Restricted access

Implications of anesthetic approach, spinal versus general, for the treatment of spinal disc herniation

Presented at the 2018 AANS/CNS Joint Section on Disorders of the Spine and Peripheral Nerves

Nikhil Sharma, Matthew Piazza, Paul J. Marcotte, William Welch, Ali K. Ozturk, H. Isaac Chen, Zarina S. Ali, James Schuster and Neil R. Malhotra

OBJECTIVE

Healthcare costs continue to escalate. Approaches to care that have comparable outcomes and complications are increasingly assessed for quality improvement and, when possible, cost containment. Efforts to identify components of care to reduce length of stay (LOS) have been ongoing. Spinal anesthesia (SA), for select lumbar spine procedures, has garnered interest as an alternative to general anesthesia (GA) that might reduce cost and in-hospital LOS and accelerate recovery. While clinical outcomes with SA or GA have been studied extensively, few authors have looked at the cost-analysis in relation to clinical outcomes. The authors’ objectives were to compare the clinical perioperative outcomes of patients who received SA and GA, as well as the direct costs associated with each modality of care, and to determine which, in a retrospective analysis, can serve as a dominant procedural approach.

METHODS

The authors retrospectively analyzed a homogeneous surgical population of 550 patients who underwent hemilaminotomy for disc herniation and who received either SA (n = 91) or GA (n = 459). All clinical and billing data were obtained via each patient’s chart and the hospital’s billing database, respectively. Additionally, the authors prospectively assessed patient-reported outcome measures for a subgroup of consecutively treated patients (n = 75) and compared quality-adjusted life year (QALY) gains between the two cohorts. Furthermore, the authors performed a propensity score–matching analysis to compare the two cohorts (n = 180).

RESULTS

Direct hospital costs for patients receiving SA were 40% higher, in the hundreds of dollars, than for patients who received GA (p < 0.0001). Furthermore, there was a significant difference with regard to LOS (p < 0.0001), where patients receiving SA had a considerably longer hospital LOS (27.6% increase in hours). Patients undergoing SA had more comorbidities (p = 0.0053), specifically diabetes and hypertension. However, metrics of complications, including readmission (p = 0.3038) and emergency department (ED) visits at 30 days (p = 1.0), were no different. Furthermore, in a small pilot group, QALY gains were statistically no different (n = 75, p = 0.6708). Propensity score–matching analysis demonstrated similar results as the univariate analysis: there was no difference between the cohorts regarding 30-day readmission (p = 1.0000); ED within 30 days could not be analyzed as there were no patients in the SA group; and total direct costs and LOS were significantly different between the two cohorts (p < 0.0001 and p = 0.0126, respectively).

CONCLUSIONS

Both SA and GA exhibit the qualities of a good anesthetic, and the utilization of these modalities for lumbar spine surgery is safe and effective. However, this work suggests that SA is associated with increased LOS and higher direct costs, although these differences may not be clinically or fiscally meaningful.