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Papers by Charles Hodge

Journal of neurosurgery, 2006

The purpose of this study was to assess the efficacy of Gamma Knife surgery (GKS) in treating pat... more The purpose of this study was to assess the efficacy of Gamma Knife surgery (GKS) in treating patients with trigeminal neuralgia (TN). Preliminary results of this study were previously reported. The updated results are reported in this paper. Ninety seven patients with TN refractory to medical or surgical management underwent GKS between September 1998 and October 2005. Fifteen patients had multiple sclerosis (MS). The radiation dose was escalated from 70 to 99 Gy. The Barrow Neurological Institute Pain Scale (BNIPS) was used to assess pain before and after GKS. Eighty-four patients were available for evaluation with a mean follow up of 8.9 months. The overall response and complete response rates were 70.2% and 36.9%, respectively. At 12 months, there was a greater improvement in BNIPS scores for patients who were treated with two isocenters compared with those treated with a single isocenter. The mean percentage of pain decrease was 56.26% compared with 11.53% (p < 0.001). Patie...

Journal of neurosurgery, 2008

The purpose of this study was to examine the results of using Gamma Knife surgery (GKS) for brain... more The purpose of this study was to examine the results of using Gamma Knife surgery (GKS) for brain metastases from classically radioresistant malignancies. The authors retrospectively reviewed the records of 76 patients with melanoma (50 patients), renal cell carcinoma (RCC; 23 patients), or sarcoma (3 patients) who underwent GKS between August 1998 and July 2007. Overall patient survival, intracranial progression, and local progression of individual lesions were analyzed. The median age of the patients was 57 years (range 18-85 years) and median Karnofsky Performance Scale (KPS) score was 80 (range 20-100). Sixty-two patients (81.6%) had uncontrolled extracranial disease. A total of 303 intracranial lesions (average 3.97 per patient, range 1-27 lesions) were treated using GKS. More than 3 lesions were treated in 30 patients (39.5%). Median GKS tumor margin dose was 18 Gy (range 8-30 Gy). Thirty-seven patients (48.7%) underwent whole brain radiation therapy. The actuarial 12-month ra...

Journal of Neurosurgery, 1980

✓ There is anatomical, pharmacological, and physiological evidence that descending systems from t... more ✓ There is anatomical, pharmacological, and physiological evidence that descending systems from the brain stem using noradrenalin and serotonin (5-hydroxytryptamine, 5-HT) participate in the control of segmental sensory processing. Study of these systems is described in this paper. L-dopa was given intravenously to cats to cause the release of noradrenalin and 5-HT. The resultant effects on the responses of dorsal horn cells to innocuous and noxious thermal stimulation of skin were determined. Using the catecholamine cell neurotoxin, 6-hydroxydopamine, the dopamine α-hydroxylase inhibitor, fusaric acid, and the tryptophan hydroxylase inhibitor, parachlorophenylalanine, the available central stores of noradrenalin or 5-HT were altered, thus allowing separation of the effects of noradrenalin and 5-HT release on dorsal horn cells. The results indicate that noradrenalin facilitates the responses of dorsal horn cells to innocuous cutaneous stimuli, and has an inhibitory effect on the res...

Journal of Neurosurgery, 2009

Journal of Neurosurgery, 1976

✓ The authors describe the sensory examinations of three patients who had undergone cervical rhiz... more ✓ The authors describe the sensory examinations of three patients who had undergone cervical rhizotomy alone and in combination with trigeminal tractotomy and section of the nervus intermedius, the glossopharyngeal nerve, and the upper portion of the vagus nerve. Following administration of L-dopa there was an increase in their pain and a decrease in the area of clinically anesthetic or analgesic skin. When methyldopa was given, the subjective and objective changes were the opposite of those elicited by L-dopa. These observations support the existence of a wider dorsal root cutaneous distribution than is usually accepted as well as significant control of cutaneous sensation by suprasegmental areas of the central nervous system. Part of the suprasegmental bias supplied to the area in the spinal cord that processes sensory information apparently occurs by way of an aminergic descending reticulospinal tract. These findings are discussed in terms of attempts totally to denervate restric...

Journal of Neurosurgical Anesthesiology, 2002

Remote cerebellar hemorrhage (RCH) is an infrequent and poorly understood complication of suprate... more Remote cerebellar hemorrhage (RCH) is an infrequent and poorly understood complication of supratentorial neurosurgical procedures. We retrospectively compared 42 patients who experienced RCH with a case-matched control cohort, to delineate risk factors associated with the occurrence of this complication. Between 1988 and 2000, 42 patients experienced RCH after supratentorial neurosurgical procedures at our institution. Diagnoses were made on the basis of postoperative computed tomographic or magnetic resonance imaging findings in all cases. The medical records for these patients were reviewed and compared with those for a control cohort of 43 patients, matched for age, sex, surgical lesion, and type of craniotomy, who were treated during the same period. RCH most commonly occurred after frontotemporal craniotomies for unruptured aneurysm repair or temporal lobectomy and was frequently an incidental finding on postoperative computed tomographic scans. However, some cases of RCH were associated with significant morbidity, and two patients died. Preoperative aspirin use and elevated intraoperative systolic blood pressure were significantly associated with RCH (P = 0.026 and P = 0.036, respectively). Pathological findings for two cases demonstrated hemorrhagic infarctions in both. RCH most commonly follows supratentorial neurosurgical procedures, performed with the patient in the supine position, that involve opening of cerebrospinal fluid cisterns or the ventricular system (such as unruptured aneurysm repair or temporal lobectomy). Preoperative aspirin use and moderately elevated intraoperative systolic blood pressure are potentially modifiable risk factors associated with the development of RCH. Although RCH can cause death or major morbidity, most cases are asymptomatic or exhibit a benign course. Cerebellar &amp;quot;sag&amp;quot; as a result of cerebrospinal fluid hypovolemia, causing transient occlusion of superior bridging veins within the posterior fossa and consequent hemorrhagic venous infarction, is the most likely pathophysiological cause of RCH.

Journal of Neurophysiology, 1990

1. In cat there are two portions of the spinothalamic tract (STT)--a ventral component, the ventr... more 1. In cat there are two portions of the spinothalamic tract (STT)--a ventral component, the ventral spinothalamic tract (VSTT) made up of axons of cells of spinal cord laminae IV-X, and a dorsolateral component, the dorsolateral spinothalamic tract (DSTT) made up of axons of cells in lamina I of the spinal cord dorsal horn. This study was designed to evaluate thalamic neuronal responses to cutaneous noxious thermal stimuli and to determine the functional importance of pathways ascending in the ventral and dorsolateral portions of the spinal cord, ipsilateral to the thalamic recording site and contralateral to the hindlimb stimulation region, for transmission of nociceptive information to the thalamus. 2. Extracellular single-unit recordings were made from 45 neurons in the ventrobasal complex (VBX) of cat thalamus. Thirty-five of these units responded either exclusively or preferentially to noxious cutaneous stimuli. Responses to noxious thermal stimuli applied to the unit's rec...

Journal of Neurosurgery, 2008

Object The brain shows remarkable capacity for plasticity in response to injury. To maximize the ... more Object The brain shows remarkable capacity for plasticity in response to injury. To maximize the benefits of current neurological treatment and to minimize the impact of injury, the authors examined the ability of commonly administered drugs, dextroamphetamine (D-amphetamine) and phenytoin, to positively or negatively affect the functional recovery of the cerebral cortex following excitotoxic injury. Methods Previous work from the same laboratory has demonstrated reorganization of whisker functional responses (WFRs) in the rat barrel cortex after excitotoxic lesions were created with kainic acid (KA). In the present study, WFRs were mapped using intrinsic optical signal imaging before and 9 days after creation of the KA lesions. During the post-lesion survival period, animals were either treated with intraperitoneal D-amphetamine, phenytoin, or saline or received no treatment. Following the survival period, WFRs were again measured and compared with prelesion data. Results The findi...

Journal of Neurosurgery, 1986

✓ The Kölliker-Fuse nucleus (KF) in the dorsolateral pons has been shown to be the major source o... more ✓ The Kölliker-Fuse nucleus (KF) in the dorsolateral pons has been shown to be the major source of catecholamine innervation of the spinal cord. This has important implications in terms of pain control mechanisms, since catecholamine-mediated mechanisms are essential for the expression of opiate and other varieties of antinociception. This study examines the effects of KF stimulation on responses of dorsal-horn cells to innocuous and noxious cutaneous stimuli in anesthetized cats. Stimulation of the KF potently inhibits the responses of dorsal-horn cells to both noxious and innocuous stimuli. The threshold for the inhibitory effect is significantly lower for responses to noxious stimuli as opposed to innocuous stimuli. The inhibitory effect is specific to the stimulus site, as evidenced by a marked decrease in the effect following small changes in the position of the stimulating electrode in the brain stem. The latency of the effects indicates a bulbospinal conduction velocity of 4 ...

Australasian Radiology, 1998

Experimental Neurology, 1984

Brain Research, 1985

The laminar distribution of spinal cord neurons projecting suprasegmentally through different fun... more The laminar distribution of spinal cord neurons projecting suprasegmentally through different funiculi was determined in the cat using horseradish peroxidase (HRP) injections combined with selective spinal cord lesions. The lesions were designed to limit the caudal transport of HRP to either the vcntral funiculi or the dorsolateral funiculus. HRP injections in the ventromedial or ventrolateral funiculi resulted in labeling primarily within laminae IV-VIII and a virtual lack of labeling within lamina 1. When the dorsolateral funiculus was injected, 20-25% of all labeled cells were located in lamina I, bilaterally. These results demonstrate that the ascending lamina I projections are through the dorsolateral funiculus.

Neurosurgery, 1997

The purpose of this study was to evaluate the technique of cortical optical imaging (COI) of intr... more The purpose of this study was to evaluate the technique of cortical optical imaging (COI) of intrinsic cortical optical signals related to neuronal activation. The specific goals of the study were to evaluate some of the technical aspects of COI and thus maximize the intensity of the image of this intrinsic signaling process and to determine the physiological reliability of COI in a well-defined animal system. The intrinsic optical signal of activated whisker barrel cortex of rat was imaged using a computer-based technique for rapid acquisition of enhanced images. Single-unit microelectrode recordings of cortical neuronal responses to whisker movement were used to confirm the locations of the whisker barrels. Narrow band incident light at 600- to 610-nm wavelength was most effective for producing optical images. Images could be obtained during activation by a single long (40 s) stimulus or by averaging the signal generated by repeated shorter (1-8 s) stimuli. Focusing slightly below the cortical surface, minimizing movement, and abolishing extraneous light were all important in increasing the signal-to-noise ratio. The locations of whisker movement-evoked cortical activity determined using COI are consistent with the known functional anatomy of rat whisker barrel cortex. The images obtained with this experimental arrangement are shown to be accurate predictors of the location of neuronal activity determined by comparing the locations of active sites identified with COI with locations of areas of neuronal activity determined using single-cell recording techniques. COI is able to rapidly identify areas of cortex containing elicited neuronal activity. The technique allows cortical activation maps to be made rapidly with a very high degree of spatial resolution. COI is reliable and consistent over time. COI, if used carefully, holds promise as an intraoperative technique to study both human and experimental animal cortical function.

Neurosurgery, 1987

Axial computed tomographic (CT) scans after intravenous contrast infusion were used to image the ... more Axial computed tomographic (CT) scans after intravenous contrast infusion were used to image the cervical carotid arteries of patients with cerebral ischemic symptoms. Standard transfemoral cervical carotid and cerebral angiography was the principal diagnostic modality used in all patients studied. The angiographic results were compared to the CT images and to the gross and microscopic endarterectomy pathological specimens, when available. Examples of the various types of abnormalities that can be visualized using CT scans are presented. The CT scan was useful for determining the presence of degenerative atheromatous changes including carotid artery calcification, subintimal hemorrhage, carotid occlusion, carotid segmental occlusion, and carotid pseudoocclusion, as well as carotid artery dissection. The scans were particularly useful for identification of atheromatous carotid artery disease when the carotid angiogram appeared nearly normal and for identifying the cause of postoperative carotid stenosis. CT scanning allows visualization of the carotid artery wall and lumen rather than just the lumen and, consequently, can sometimes add helpful information about the pathological processes affecting this artery.

Neurosurgery, 2000

The purpose of this report is to discuss the technical aspects of operating on colloid cysts thro... more The purpose of this report is to discuss the technical aspects of operating on colloid cysts through a transventricular approach, with rigid endoscopes. Twelve patients underwent 14 endoscopic operations in attempts to treat their colloid cysts. All patients were symptomatic, with headache being the most common complaint (8 of 12 patients). Six patients in this series exhibited enlarged ventricles associated with their colloid cysts. Using rigid endoscopes of < or =3.5-mm diameter, the cysts were inspected and fenestrated. Both hard and soft cyst contents were evacuated, and then the walls of the cysts were coagulated inside and outside. External ventriculostomy tubes were usually placed. Technical obstacles to successful completion of endoscopic colloid cyst surgery are discussed. For 11 of the 12 patients, the colloid cysts could be treated via an endoscopic approach. The mean follow-up time was 173 weeks, and the median follow-up time was 125 weeks. For the 12th patient, bilateral scarring of the foramina of Monro precluded direct surgery; therefore, a septostomy was performed and a ventriculoperitoneal shunt was placed. Endoscopic transventricular surgery should be considered for the treatment of colloid cysts.

Neurosurgery, 1982

Among 140 cases of chronic extracerebral fluid collections treated surgically, 7 cases (5%) of in... more Among 140 cases of chronic extracerebral fluid collections treated surgically, 7 cases (5%) of intracerebral hematoma occurring immediately after drainage were encountered. In none of the patients was a preoperative intracerebral clot or contusion identified by either computed tomographic scan or angiography. One patient had pre-existing systemic hypertension. Five of the patients had chronic subdural hematomas, 1 had a subdural hygroma and had been previously radiated for medulloblastoma, and 1 patient had a middle fossa arachnoid cyst. Four of the group had had craniotomies and three had undergone trephination for the primary lesion. The postoperative intracerebral hematomas were manifest by rapid deterioration of consciousness and focal neurological findings occurring usually immediately (but, in 2 cases, a few days after) the original procedure. Five patients underwent secondary craniotomy and 2 had external drainage. Despite rapid treatment, 2 of the patients died, 4 were left with severe disability, and only 1 survived intact. None of the patients had identifiable coagulopathy, and only 1 patient was hypertensive in the immediate postoperative period. The factors that all of the patients had in common were preoperative increased intracranial pressure and shift of the midline structures, as well as rapid surgical decompression of the initial lesion. Possible pathogenic mechanisms include hemorrhage into previously undetected areas of contusion, a sudden increase in cerebral blood flow combined with faulty autoregulation, and damage to parenchymal vessels secondary to rapid intra- or postoperative shift of the intracranial contents. Perhaps this devastating complication can be avoided if closed system drainage is used for the treatment of chronic surface collections.

Journal of Clinical Neuroscience, 2014

Effectiveness of Gamma Knife radiosurgery (GKRS: Elekta AB, Stockholm, Sweden) for patients with ... more Effectiveness of Gamma Knife radiosurgery (GKRS: Elekta AB, Stockholm, Sweden) for patients with metastatic brain disease and the prognostic factors influencing their survival were analyzed in a 5 year retrospective data analysis (July 2001 to June 2006). Kaplan-Meier survival curves were constructed using univariate and multivariate analyses with the respective salient prognostic factors. This study analyzed data on 330 patients with brain metastases who underwent GKRS. Lung carcinoma (55%) was the most common primary cancer followed by breast (17.8%), melanoma (9.4%), colorectal (4.8%) and renal (3.9%). The median survival for all patients was 8 months. Survival ranged from 13 months for breast metastases, 10 months for renal, and 8 months for lung to 5 months for colorectal and melanoma. Mean age of patients was 58.5 years (range 18-81). Melanoma patients were younger with a mean age of 49 and also had the highest number of lesions (3.8) when compared to patients with renal (2.5), lung (2.8), colorectal (3) and breast (3.6). When stratified according to the number of lesions patient survival was 8 months (one to three lesions), 7.5 months (four or five lesions) and 7 months (six lesions or more). Mean Karnofsky Performance Status score (KPS) was 77 and survival dropped significantly from 8 months to 4.5 months if KPS was less than 70. Survival improved with a KPS of 70 or more, regardless of the number of lesions treated. Selection of patients based on the number of lesions may not be justified. A prospective trial is required to further define the prognostic factors affecting survival.