The Insertion of Electrodes in the Brain for Electrophysiological Recording or Chronic Stimulation Is Not Associated With Any Biochemically Detectable Neuronal Injury.

OBJECTIVE: The aim of this study was to evaluate the degree of brain tissue injury that could be potentially induced by the introduction of a) microrecording electrodes, b) macrostimulation electrodes, or c) chronic stimulation electrodes. We aimed to evaluate whether the use of five simultaneous microrecording tracks is associated with any brain injury not detectable by conventional imaging such as CT or MRI. MATERIALS AND METHODS: The study included 61 patients who underwent surgery for implantation of 121 DBS leads. In all cases, five simultaneous tracts were utilized for microelectrode recordings. All patients underwent measurements of serum S-100b at specific time points as follows: a) prior to the operation, and b) intraoperatively at specific stages of the procedure: 1) after opening the burr hole, 2) after the insertion of microrecording electrodes, 3) during macrostimulation, 4) at the end of the operation, and 5) on the first postoperative day. RESULTS: The levels of serum S-100B protein remained within the normal range during the entire period of investigation in all patients with the exception of two cases. In both patients, the procedure was complicated by intraparenchymal hemorrhage visible in neuro-imaging. The first patient developed a small intraparenchymal hemorrhage, visible on the postoperative MRI, with no neurological deficit. The second patient experienced a focal epileptic seizure after the insertion of the right DBS chronic lead and the postoperative CT scan revealed a right frontal lobe hemorrhage. CONCLUSION: These results strongly indicate that the insertion of either multiple recording electrodes or the implantation of chronic electrodes in DBS does not increase the risk of brain hemorrhage or of other intracranial complications, and furthermore it does not cause any biochemically detectable brain tissue damage.

Surgical and hardware complications of deep brain stimulation. A seven-year experience and review of the literature.

PURPOSE: Deep brain stimulation (DBS) has been established as a safe and efficient method for the treatment of various movement disorders. As the emerging applications continue to expand and more centers become eligible for the procedure, complication rates and complication avoidance become increasingly important. Our aim was to report the DBS-related complication in our department over the last 7 years, compare our rates with those reported in the literature, and highlight those practices that will aid complications avoidance. PATIENTS AND METHODS: Since 2003, 106 patients underwent DBS for various pathologies in our department. There were 38 (36%) females and 68 (64%) males with a mean age of 57 years. Preoperative diagnoses included Parkinson's disease (n = 88), dystonia (n = 12), tremor (n = 3), epilepsy (n = 1), obsessive-compulsive disorder (n = 1), and central pain syndrome (n = 1). Surgical and hardware-related complications, their treatment, and outcome were recorded and compared with those reported in the literature. RESULTS: There were 12 procedure-related complications (11.3% of patients, 5.7% of the procedures). These included death (n = 1), aborted procedure (n = 1), postoperative respiratory distress (n = 3), intracranial hemorrhage (n = 2), epilepsy (n = 1), postoperative confusion or agitation (n = 3), and malignant neuroleptic syndrome (n = 1). Hardware-related complications presented in 4.3% of the procedures and included infection (five patients, 4.7%), electrode breakage (0.94%), lead migration or misplacement (0.94%), and stricture formation (two patients, 1.9%). CONCLUSIONS: Complication rates after DBS surgery remain low, proving that DBS is not only effective but also safe. Certain strategies do exist in order to minimize complications.

A modified speculum for transsphenoidal surgery: technical note.

This technical note presents the advantages of a modified nasal speculum for the translabial-endonasal transsphenoidal approach to the sphenoid sinus and sella for surgery on lesions of the pituitary. The width of the upper lateral wings of the speculum was reduced by half over approximately three fourths of their length. This increases interior clearance and makes it easier to introduce the instruments used during transsphenoidal operations. We performed 50 transsphenoidal procedures for pituitary adenomas using the remodeled speculum. Three experienced surgeons evaluated the visual field and instrument passage through it, and they found it superior to the conventional design. The modification resulted in marked reduction of the overall operation duration. In conclusion, the more open translabial-transnasal speculum described here definitely facilitates the transsphenoidal approach to the pituitary.

Spinal synovial cysts: pathogenesis, diagnosis and surgical treatment in a series of seven cases and literature review.

This study is designed based on the retrospective analysis of patients treated in the Neurosurgical Department of two major hospitals and review of the literature. The aim of this study is to evaluate the efficacy of surgery and address controversial issues in the treatment of symptomatic lumbar intraspinal synovial cysts. Spinal juxtafacet cysts (synovial and ganglion cysts) are a rare cause of low back and radicular leg pain. Although the relevant reports in the international literature are increasing, the controversy about conservative versus surgical treatment and the need for concomitant fusion still exists. Data from seven patients (age range 58-69 years, mean age 61 years) with low back and radicular leg pain due to a lumbar facet joint cyst were retrospectively analyzed. Demographic data, cyst level, presence of concomitant local pathology, treatment and results of treatment were recorded. A follow-up of at least 6 months (range 6-48 months) was conducted and results were noted. All patients had back pain, while five also experienced unilateral radicular leg pain and one had bilateral leg pain. One patient had neurogenic claudication. MRI identified the cyst and highlighted underlying pathology in all cases. All patients underwent surgical cyst excision. No fusion was performed. Post-operatively, all patients showed a total resolution of symptoms with sustained benefit at final evaluation. Review of the literature revealed a trend towards surgery, as this is correlated to a more favorable outcome compared with conservative treatment. Fusion should be performed on a case-by-case basis only. Surgery is a safe and effective treatment choice in this increasingly appearing ailment. A prospective, randomized trial should clarify issues under debate.

Asymptomatic massive subdural hematoma in a patient with bitemporal agenesis and bilateral temporal arachnoid cysts.

The case of a 38-year-old man with a history of chronic migraine is reported. Despite a 3 week history of changes in his migraine pattern, a normal neurologic examination led to conservative treatment. He later presented with worsening headaches and imbalance; tendon reflexes were increased on the right side, and brain computed tomography and magnetic resonance imaging revealed a massive subacute subdural hematoma over the left hemisphere, developing on the grounds of bilateral temporal agenesis. The presence of bilateral temporal arachnoid cysts along with bitemporal agenesis altered clinical findings, causing only mild symptoms where an otherwise acute and devastating neurologic deterioration would be expected.

Impact of age on complications and outcome in meningioma surgery.

BACKGROUND: Surgery for benign brain tumors in elderly patients without severe general health problems is an acceptable practice, as results are comparable with the ones of younger patients. Nevertheless, the hypothesis that operative complications and perioperative incidents could differ between the 2 age groups should be controlled; and age-specific strategies in operative technique and perioperative care may be useful. METHODS: Medical records of 348 patients were reviewed. Demographic data (age, sex), rate of excision, complications of the immediate postoperative period, neurological outcome, and mortality were recorded; and statistical evaluation comparing 2 age groups (19-64 and 65-84 years of age) was performed. RESULTS: The "young" age group consisted of 240 patients, whereas the "elderly" one had 108. Tumor removal rate was not significantly different in the 2 groups. The elderly age group included significantly more "complicated cases." Regarding each complication, postoperative hematoma, infections, and deep vein thrombosis were more frequent in elderly patients, presenting various degrees of statistical significance, whereas postoperative brain edema, hydrocephalus, and cardiorespiratory incidents presented no statistically significant difference. Finally, more elderly patients presented neurological deterioration, although mortality was not significantly different. CONCLUSIONS: Operation for intracranial meningioma in elderly patients is justified as long as detailed preoperative evaluation is performed. Planning of modified protocols including intraoperative technical aspects, careful use of steroids antibiotics, and prophylactic low molecular weight heparin, and early mobilization is necessary for optimizing operative outcome of elderly patients.

Long-term air-exposed functioning hydrocephalus valve with no infection.

One of the reasons for shunt infection is valve erosion through the skin. In such cases, it is common practice to instantly relocate the shunt to avoid infection. We present a 77-year-old female patient with a 15-month history of hydrocephalus valve extrusion. Despite her poor mental status, clinical condition and hygiene, and the prolonged extrusion period, she developed neither a local nor a cerebrospinal fluid (CSF) infection. The patient was ultimately treated with shunt removal and repositioning. An extensive literature review revealed no previous report of such a case. This case indicates that under rare conditions, central nervous system (CNS) implantable devices might not become contaminated and may remain functional, even if they remain exposed for prolonged periods.

Endocrine alterations in critically ill patients with stroke during the early recovery period.

INTRODUCTION: Endocrine abnormalities in critically ill patients with stroke during the early recovery period have not been well characterized. METHODS: To investigate this issue, 33 consecutive mechanically ventilated patients (27 men) with hemorrhagic (n = 21) or ischemic (n = 12) stroke having a mean age of 57 +/- 12 years were studied. Glasgow Coma Scale score on admission in the hospital was 8 +/- 3. The following basal hormones were measured within 72 hours postextubation: cortisol, corticotropin (ACTH), free thyroxine, tri-iodothyronine, thyroid-stimulating hormone, testosterone, estradiol, follicle-stimulating hormone, luteinizing hormone, growth hormone, and insulin-like growth factor (IGF)-1. Subsequently, a low-dose (1 microg) ACTH stimulation test was performed. RESULTS: Twenty-six (79%) patients showed endocrine alterations. The most common change was low IGF-1 levels compatible with growth hormone deficiency (45%), followed by hypogonadism (39%), thyroid dysfunction (36%), and cortisol hyporesponsiveness (33%). CONCLUSION: Neuroendocrine changes occur with high frequency in critically ill patients with stroke during the early recovery period. It remains to be determined whether these changes have implications for functional and/or clinical outcome.

Functional outcome of intrathecal baclofen administration for severe spasticity.

PURPOSE: To estimate the functional benefit in patients with severe spasticity treated with intrathecal baclofen infusion through an implantable pump and to stress the need for functional assessment of these patients with a functional scale. PATIENTS AND METHODS: Between 1999 and 2003, 22 patients with a long history of severe and disabling pharmaceutically intractable spasticity, underwent implantation of a pump for continuous intrathecal baclofen infusion. The patients were subdivided into two categories according to the aetiology of spasticity: 15 had Multiple Sclerosis and seven had suffered a Spinal Cord Injury at different levels (from C4 to T11). Clinical status was assessed with the Ashworth and Penn spasm scales. Functional benefits were evaluated with the Barthel index score and pain relief with a self-reported visual analogue pain scale. RESULTS: Postoperatively, all patients presented improvement in spasticity, reduction of spasm frequency, significant improvement in functional status, enhancement of life comfort and reduction of pain. CONCLUSION: Reduction of spasticity and spasms achieved with intrathecally delivered baclofen, leads to functional improvement and pain relief.

Lumbar synovial cyst as a cause of low back pain and acute radiculopathy: a case report.

The authors report the case of a 69-year old female with a persistent history of low back pain. Plain lumbar radiographs, performed at symptom initiation, revealed lumbar spondylolisthesis. Low back pain was attributed to this, and the patient received conservative treatment with partial relief of symptoms. Four years later, and as a result of acute onset of radicular symptoms, a lumbar spine magnetic resonance imaging scan was performed, revealing an epidural cystic lesion. The cyst was removed, and histopathology revealed a synovial cyst.

Serum S-100B as an indicator of early postoperative deterioration after meningioma surgery.

BACKGROUND: S-100B protein is an established serum marker of primary and secondary brain damage in head injury and stroke. Despite major progress in neurophysiologic monitoring, there are still difficulties in the early identification and quantification of evolving edema or trauma after craniotomy for tumor. In this study we aimed to correlate serum S-100B values with early postoperative neurologic course as well as late outcome in meningioma surgery. METHODS: We enrolled 50 consecutive patients who underwent meningioma resection. Serum S-100B was measured preoperatively and postcraniotomy for 7 consecutive days. Twenty-five patients (50%) developed immediate postoperative neurologic deterioration, and 15 (30%) had unfavorable 6-month outcomes. We used the Mann-Whitney U-test to assess the association of S-100B with all variables of interest. We used multiple logistic regression to search for the most significant predictor of postoperative deterioration. RESULTS: Increased S-100B was highly correlated with larger tumors, intraoperative difficulties, postcraniotomy acute deterioration, and long-term poor outcome. In addition, multiple logistic regression showed that age, sex, site, preoperative edema, history of meningioma resection, extent of resection, and histologic type did not correlate with postoperative increases in S-100B. Furthermore, patients with postoperative S-100B values >0.4 microg/L had increased risk of deterioration (relative risk = 9.0; 95% confidence interval, 2.4-34; P <0.0001) and of poor ultimate outcome (relative risk = 11; 95% confidence interval, 1.6-77; P = 0.002). CONCLUSIONS: After meningioma excision, postcraniotomy increases in serum S-100B appear to be an early indicator of short-term postoperative neurologic deterioration and of a poor longer-term outcome.

High incidence of neuroendocrine dysfunction in long-term survivors of aneurysmal subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: To investigate the incidence, pattern, and magnitude of neuroendocrine changes in long-term survivors of aneurysmal subarachnoid hemorrhage (SAH). METHODS: Thirty patients (16 women) with a mean age of 50+/-13 years underwent endocrine assessment between 12 and 24 months after aneurysmal SAH. SAH severity was graded clinically by the Hunt & Hess scale (median, II) and radiologically by the Fisher classification (median, II). Patients underwent measurement of basal hormone levels and dynamic assessment by the low-dose (1 microg) corticotropin stimulation test. Functional outcome was examined concurrently with endocrine testing by the modified Rankin Scale and the Barthel Index. RESULTS: Of the 30 patients tested, 14 patients (47%) showed isolated or combined endocrine abnormalities. These included low insulin-like growth factor 1 levels compatible with growth hormone deficiency in 37%, hypogonadism in 13%, and cortisol hyporesponsiveness to the low-dose corticotropin stimulation test in 10%; thyroid dysfunction in the form of subclinical hypothyroidism was observed in 7% of patients. Median modified Rankin Scale and Barthel Index at the time of endocrine testing were 1 and 100, respectively. There was no correlation between the presence of endocrine dysfunction and SAH severity indices or functional outcome scores. CONCLUSIONS: Long-term survivors of aneurysmal SAH frequently exhibit endocrine changes, with growth hormone and gonadal deficiencies predominating. Thus, screening of pituitary function is recommended in patients surviving SAH. The relationship between late hormonal alterations and functional outcome in patients with SAH warrants further study.

Elevated serum S-100B protein as a predictor of failure to short-term return to work or activities after mild head injury.

Protein S-100B is an established serum marker of primary and secondary brain damage and stroke. A group of patients after mild head injury (MHI) develop post-concussion symptoms that interfere with the ability in the short-term to return to work or undertake certain activities. The aim of this study was to examine the correlation of serum S-100B with short-term outcome after MHI. We studied 100 subjects who were referred to the Emergency Department (ED) after a MHI. All subjects had a GCS of 15 either with or without loss of consciousness (LOC) and/or post-traumatic amnesia (PTA). Serum S-100B was collected within 3 h from the injury and a value of > or = 0.15 microg/L was considered as abnormal. Subjects with other injuries, including scalp or cervical spine, were excluded, as well as those with alcohol/narcotic drug consumption or history of serious physical/mental illness. An independent observer measured the return to work/activities within one week. Thirty-two (32%) subjects had elevated S-100B. The failure to return to work/activities was significantly correlated with elevated S-100B: subjects with increased S-100B had a failure rate of 37.5% versus 4.9% of those with normal values (p = 0.0001). In MHI, the elevated S-100B seemed to correlate with an unfavorable short-term outcome. This might be useful in (1) selecting patients who need closer observation, hospitalization, and further investigations (such as CT scan or MRI), and (2) the prognosis of genuine post-concussion symptoms, that interfere with return to work or activities, versus other causes such as premorbid personality, labyrinthine dysfunction, whiplash syndrome, postinjury stress, occupational injury, litigation, and malingering.

Silent radiological imaging time in patients with brain metastasis.

Cerebral metastasis is a common finding in patients with systemic carcinoma and is an indication for progress of the disease. When brain metastases occur, they lead to a considerable decrease in both survival and the quality of life, in patients who otherwise might be functional. Furthermore, the location, size and number of such lesions, play a decisive role in management and prognosis. Even though early diagnosis and treatment is curative in rare cases, it may lead to a useful remission of the central nervous system (CNS) symptoms, enhance the patient's quality of life and prolong survival. The radiological exams established in the diagnosis of this condition, include computed tomography (CT) scan or magnetic resonance imaging (MRI). In cases of "micrometastatic" disease though, these exams may be pronounced as normal. This retrospective study was performed in patients with advanced systemic disease, who presented with neurological findings of intracranial mass lesion, in the absence of radiological evidence. Early-occurring symptoms were evaluated in accordance to location of the primary disease and follow-up with repetitive MRI scans was performed, in an attempt to confirm the diagnosis and facilitate prompt and appropriate treatment.

Endocrine abnormalities in critical care patients with moderate-to-severe head trauma: incidence, pattern and predisposing factors.

OBJECTIVE: To investigate the incidence and type of endocrine abnormalities in critical care patients with traumatic brain injury (TBI) and to examine their relationships to possible predisposing factors. DESIGN: Prospective study. SETTING: General intensive care unit in a university hospital. PATIENTS AND PARTICIPANTS: Thirty-four TBI patients (27 men, 7 women), having a mean age of 37+/-16 years, were studied after weaning from mechanical ventilation. INTERVENTIONS: Baseline endocrine assessment was carried out by measuring cortisol, corticotropin, dehydroepiandrosterone sulfate, free thyroxine, thyrotropin (TSH), testosterone, oestradiol, follicle stimulating hormone (FSH), luteinizing hormone, prolactin, growth hormone and insulin-like growth factor I. Dynamic evaluation was performed by human corticotropin releasing hormone and growth hormone releasing hormone in all patients. Male patients underwent additional investigation with gonadotropin-releasing hormone. Severity of neurological derangement was graded according to Glasgow Coma Scale (GCS), Marshall Computerized Tomographic Classification and intracranial pressure (ICP) levels. MEASUREMENTS AND RESULTS: Eighteen of the 34 patients (53%) had an abnormal result in at least one hormonal axis tested, with cortisol hyporesponsiveness and gonadal dysfunction being equally common, affecting 24% of patients. Endocrine abnormalities were associated with a higher brain CT-scan classification score ( p=0.02). The GCS on admission correlated positively with baseline FSH (r=0.37, p=0.03), peak FSH (r=0.41, p=0.03), testosterone (r=0.44, p=0.02) and TSH (r=0.39, p=0.03). There were no relations between ICP(max) and any baseline or dynamic hormone measurements. CONCLUSIONS: Patients with TBI receiving critical care show changes in their neuroendocrine responses, which depend upon clinical and radiological measures of head injury severity. Most common abnormalities include cortisol hyporesponsiveness and hypogonadism.

The low-dose corticotropin stimulation test in acute traumatic and non-traumatic brain injury: incidence of hypo-responsiveness and relationship to outcome.

OBJECTIVE: To investigate adrenal responses to the low-dose corticotropin (ACTH) stimulation test in acute traumatic or non-traumatic brain injury (BI) and to assess its value in predicting outcome. DESIGN: Prospective study. SETTING. Intensive care unit (ICU) in a university hospital. PATIENTS AND PARTICIPANTS: Seventy-five patients with acute BI, with a median age of 45 years were investigated. BI was due to trauma ( n=51), ischemic stroke ( n=17), subarachnoid hemorrhage ( n=4) or intracerebral hemorrhage (n=3). INTERVENTIONS: Blood was taken on day 16 (median) after admission to the ICU to determine baseline cortisol and ACTH. Thereafter, a low-dose stimulation test (LDST) was performed: 1 microg of tetracosactrin was injected and 30 min later a second blood specimen was obtained to measure stimulated cortisol. Patients having a stimulated cortisol below 500 nmol/l were defined as non-responders to the LDST. MEASUREMENTS AND RESULTS: Median baseline and stimulated cortisol were 491 nmol/l and 690 nmol/l, respectively. The median increment in cortisol was 154 nmol/l (range 5-579 nmol/l). Mean ACTH was 46+/-21 pg/ml. Ten (13%) patients were non-responders to the LDST; these had a higher mortality rate compared to patients with adequate cortisol production (70 vs 32%, p=0.034). Logistic regression analysis revealed that APACHE II ( p<0.001), Glasgow Coma Scale (GCS) ( p=0.04) and age ( p=0.02) were independent outcome predictors. In contrast, the increment in cortisol ( p=0.26) did not add to outcome prediction. CONCLUSIONS: Adrenal hypo-responsiveness in the setting of acute traumatic or non-traumatic BI is not an independent outcome predictor in the presence of high APACHE II, low GCS and older age.

Hypothalamic-pituitary-adrenal axis dysfunction in critically ill patients with traumatic brain injury: incidence, pathophysiology, and relationship to vasopressor dependence and peripheral interleukin-6 levels.

OBJECTIVE: To investigate hypothalamic-pituitary-adrenal axis function in patients requiring mechanical ventilation for traumatic brain injury and to assess the relation of hypothalamic-pituitary-adrenal axis abnormalities with vasopressor dependence and peripheral cytokine levels. DESIGN: Prospective study. SETTING: General intensive care unit in a university teaching hospital. PATIENTS: Forty patients (33 men and 7 women) with moderate to severe traumatic brain injury (mean age, 37 +/- 16 yrs) were studied the day after termination of mechanical ventilation (7-60 days after trauma). INTERVENTIONS: First, a morning blood sample was obtained to measure baseline cortisol, corticotropin, interleukin-6, and tumor necrosis factor alpha. Subsequently, 1 microg of synthetic corticotropin was injected intravenously, and 30 mins later, a second blood sample was drawn to determine stimulated plasma cortisol. Based on data derived from healthy volunteers, patients having stimulated cortisol levels <18 microg/dL were defined as nonresponders to the low-dose stimulation test. Thirty-one patients underwent also a human corticotropin releasing hormone test. MEASUREMENTS AND MAIN RESULTS: In traumatic brain injury patients, mean baseline and low-dose stimulation test-stimulated cortisol levels were 17.2 +/- 5.4 microg/dL and 24.0 +/- 6.6 microg/dL, respectively. The median increment in cortisol was 5.9 microg/dL. Basal corticotropin levels ranged from 3.9 to 118.5 pg/mL. Six of the 40 patients (15%) failed the low-dose stimulation test. The human corticotropin releasing hormone test (performed in 26 responders and five nonresponders) revealed diminished cortisol release only in the low-dose stimulation test nonresponder patients. Corticotropin responses to corticotropin releasing hormone were consistent with both primary (three patients) and/or secondary (two patients) adrenal dysfunction. In retrospect, nonresponders to the low-dose stimulation test more frequently required vasopressors (6/6 [100%] vs. 16/34 [47%]; p =.02) and for a longer time interval (median, 0 vs. 293 hrs; p =.006) compared with responders. Furthermore, nonresponders had higher interleukin-6 levels compared with responders (56.03 vs. 28.04 pg/mL; p =.01), whereas tumor necrosis factor alpha concentrations were similar in the two groups (2.42 vs. 1.55 pg/mL; p =.53). CONCLUSIONS: Adrenal cortisol secretion after dynamic stimulation is deficient in a subset of critically ill patients with moderate to severe head injury. This disorder is associated with prior vasopressor dependency and higher interleukin-6 levels.