Matthew S. Willsey, Kelly L. Collins, Erin C. Conrad, Heather A. Chubb and Parag G. Patil
Trigeminal neuralgia (TN) is an uncommon idiopathic facial pain syndrome. To assist in diagnosis, treatment, and research, TN is often classified as type 1 (TN1) when pain is primarily paroxysmal and episodic or type 2 (TN2) when pain is primarily constant in character. Recently, diffusion tensor imaging (DTI) has revealed microstructural changes in the symptomatic trigeminal root and root entry zone of patients with unilateral TN. In this study, the authors explored the differences in DTI parameters between subcategories of TN, specifically TN1 and TN2, in the pontine segment of the trigeminal tract.
The authors enrolled 8 patients with unilateral TN1, 7 patients with unilateral TN2, and 23 asymptomatic controls. Patients underwent DTI with parameter measurements in a region of interest within the pontine segment of the trigeminal tract. DTI parameters were compared between groups.
In the pontine segment, the radial diffusivity (p = 0.0049) and apparent diffusion coefficient (p = 0.023) values in TN1 patients were increased compared to the values in TN2 patients and controls. The DTI measures in TN2 were not statistically significant from those in controls. When comparing the symptomatic to asymptomatic sides in TN1 patients, radial diffusivity was increased (p = 0.025) and fractional anisotropy was decreased (p = 0.044) in the symptomatic sides. The apparent diffusion coefficient was increased, with a trend toward statistical significance (p = 0.066).
Noninvasive DTI analysis of patients with TN may lead to improved diagnosis of TN subtypes (e.g., TN1 and TN2) and improve patient selection for surgical intervention. DTI measurements may also provide insights into prognosis after intervention, as TN1 patients are known to have better surgical outcomes than TN2 patients.
Jason K. Chu, Abdullah H. Feroze, Kelly Collins, Lynn B. McGrath Jr., Christopher C. Young, John R. Williams and Samuel R. Browd
Placement of an external ventricular drain (EVD) is a common and potentially life-saving neurosurgical procedure, but the economic aspect of EVD management and the relationship to medical expenditure remain poorly studied. Similarly, interinstitutional practice patterns vary significantly. Whereas some institutions require that patients with EVDs be monitored strictly within the intensive care unit (ICU), other institutions opt primarily for management of EVDs on the surgical floor. Therefore, an ICU burden for patients with EVDs may increase a patient’s costs of hospitalization. The objective of the current study was to examine the expense differences between the ICU and the general neurosurgical floor for EVD care.
The authors performed a retrospective analysis of data from 2 hospitals within a single, large academic institution—the University of Washington Medical Center (UWMC) and Seattle Children’s Hospital (SCH). Hospital charges were evaluated according to patients’ location at the time of EVD management: SCH ICU, SCH floor, or UWMC ICU. Daily hospital charges from day of EVD insertion to day of removal were included and screened for days that would best represent baseline expenses for EVD care. Independent-samples Kruskal-Wallis analysis was performed to compare daily charges for the 3 settings.
Data from a total of 261 hospital days for 23 patients were included in the analysis. Ten patients were cared for in the UWMC ICU and 13 in the SCH ICU and/or on the SCH neurosurgical floor. The median values for total daily hospital charges were $19,824.68 (interquartile range [IQR] $12,889.73–$38,494.81) for SCH ICU care, $8,620.88 (IQR $6,416.76–$11,851.36) for SCH floor care, and $10,002.13 (IQR $8,465.16–$12,123.03) for UWMC ICU care. At SCH, it was significantly more expensive to provide EVD care in the ICU than on the floor (p < 0.001), and the daily hospital charges for the UWMC ICU were significantly greater than for the SCH floor (p = 0.023). No adverse clinical event related to the presence of an EVD was identified in any of the settings.
ICU admission solely for EVD care is costly. If safe EVD care can be provided outside of the ICU, it would represent a potential area for significant cost savings. Identifying appropriate patients for EVD care on the floor is multifactorial and requires vigilance in balancing the expenses associated with ICU utilization and optimal patient care.
Anthony C. Wang, George M. Ibrahim, Andrew V. Poliakov, Page I. Wang, Aria Fallah, Gary W. Mathern, Robert T. Buckley, Kelly Collins, Alexander G. Weil, Hillary A. Shurtleff, Molly H. Warner, Francisco A. Perez, Dennis W. Shaw, Jason N. Wright, Russell P. Saneto, Edward J. Novotny, Amy Lee, Samuel R. Browd and Jeffrey G. Ojemann
The potential loss of motor function after cerebral hemispherectomy is a common cause of anguish for patients, their families, and their physicians. The deficits these patients face are individually unique, but as a whole they provide a framework to understand the mechanisms underlying cortical reorganization of motor function. This study investigated whether preoperative functional MRI (fMRI) and diffusion tensor imaging (DTI) could predict the postoperative preservation of hand motor function.
Thirteen independent reviewers analyzed sensorimotor fMRI and colored fractional anisotropy (CoFA)–DTI maps in 25 patients undergoing functional hemispherectomy for treatment of intractable seizures. Pre- and postoperative gross hand motor function were categorized and correlated with fMRI and DTI findings, specifically, abnormally located motor activation on fMRI and corticospinal tract atrophy on DTI.
Normal sensorimotor cortical activation on preoperative fMRI was significantly associated with severe decline in postoperative motor function, demonstrating 92.9% sensitivity (95% CI 0.661–0.998) and 100% specificity (95% CI 0.715–1.00). Bilaterally robust, symmetric corticospinal tracts on CoFA-DTI maps were significantly associated with severe postoperative motor decline, demonstrating 85.7% sensitivity (95% CI 0.572–0.982) and 100% specificity (95% CI 0.715–1.00). Interpreting the fMR images, the reviewers achieved a Fleiss’ kappa coefficient (κ) for interrater agreement of κ = 0.69, indicating good agreement (p < 0.01). When interpreting the CoFA-DTI maps, the reviewers achieved κ = 0.64, again indicating good agreement (p < 0.01).
Functional hemispherectomy offers a high potential for seizure freedom without debilitating functional deficits in certain instances. Patients likely to retain preoperative motor function can be identified prior to hemispherectomy, where fMRI or DTI suggests that cortical reorganization of motor function has occurred prior to the operation.