Outcome prediction in moderate and severe traumatic brain injury: a focus on computed tomography variables.

BACKGROUND: With this study we aimed to design validated outcome prediction models in moderate and severe traumatic brain injury (TBI) using demographic, clinical, and radiological parameters. METHODS: Seven hundred consecutive moderate or severe TBI patients were included in this observational prospective cohort study. After inclusion, clinical data were collected, initial head computed tomography (CT) scans were rated, and at 6 months outcome was determined using the extended Glasgow Outcome Scale. Multivariate binary logistic regression analysis was applied to evaluate the association between potential predictors and three different outcome endpoints. The prognostic models that resulted were externally validated in a national Dutch TBI cohort. RESULTS: In line with previous literature we identified age, pupil responses, Glasgow Coma Scale score and the occurrence of a hypotensive episode post-injury as predictors. Furthermore, several CT characteristics were associated with outcome; the aspect of the ambient cisterns being the most powerful. After external validation using Receiver Operating Characteristic (ROC) analysis our prediction models demonstrated adequate discriminative values, quantified by the area under the ROC curve, of 0.86 for death versus survival and 0.83 for unfavorable versus favorable outcome. Discriminative power was less for unfavorable outcome in survivors: 0.69. CONCLUSIONS: Outcome prediction in moderate and severe TBI might be improved using the models that were designed in this study. However, conventional demographic, clinical and CT variables proved insufficient to predict disability in surviving patients. The information that can be derived from our prediction rules is important for the selection and stratification of patients recruited into clinical TBI trials.

Pulsed radiofrequency treatment for trigeminal neuralgia.

BACKGROUND: Pulsed radiofrequency (PRF) treatment is defined as the delivery of short pulses of radiofrequency via a needle tip, which does not result in an actual thermal lesions. There are mixed views regarding the use of PRF for trigeminal neuralgia (TN). In our opinion, one of the main reasons for the contrasting views is the insufficient PRF dose employed in previous studies. In a recent study on the effects of PRF on resiniferatoxin-induced neuropathic pain in an animal model, the anti-allodynic effects of PRF were significantly greater when the PRF exposure duration was increased from 2 to 6 minutes. OBJECTIVES: The primary objective of this retrospective study is to report the results for 36 consecutive patients who underwent PRF treatment for TN, for 6 minutes at 45 V at a pulsed frequency of 4 Hz and a pulse width of 10 ms. PATIENTS AND METHODS: For the study, we obtained procedural records of 36 consecutive patients. Their current state of pain was evaluated over a telephonic survey and the post-procedural data at 2, 6, and 12 months were retrieved thereafter from the patient records. The main outcome measure was excellent pain relief (more than 80%), which was assessed at 2, 6, and 12 months. RESULTS: The percentages of patients who showed excellent pain relief (> 80% pain relief) at 2, 6, and 12 months were 73.5% (25/34), 61.8% (21/34), and 55.9% (19/34), respectively. The percentages of patients showing satisfactory pain relief (50-80% pain relief) at 2, 6, and 12 months were 14.7% (5/34), 17.6% (6/34), and 17.6% (6/34), respectively, and those of patients showing less than satisfactory pain relief (< 50% pain relief) at 2, 6, and 12 months were 11.8% (4/34), 20.6% (7/34), and 23.5% (8/34), respectively. No complications were reported, and none of the patients required hospitalization. CONCLUSIONS: PRF of the trigeminal ganglion should be further evaluated as an alternative treatment method for TN.

The use of laminectomy for the placement of a percutaneous spinal cord stimulation electrode.

OBJECTIVE: The placement of a percutaneous electrode for trial stimulation to evaluate the effectiveness of spinal cord stimulation can be impossible because of epidural adhesions from previous spinal surgeries. The authors would like to describe a combination of techniques in order to place a percutaneous lead for a test phase. MATERIALS AND METHODS: Technical report of an illustrative case where a partial laminectomy was used to assist a percutaneous lead placement. RESULTS: Adequate trial spinal cord stimulation with a single lead electrode at the right target area was possible. CONCLUSION: This case demonstrates the possibility to use a combination of an open and percutaneous technique for trial spinal cord stimulation in patients with prior operations in the target area of stimulation.

Percutaneous thoracic intervertebral disc nucleoplasty: technical notes from 3 patients with painful thoracic disc herniations.

Symptomatic thoracic disc herniation is an uncommon condition and early surgical approaches were associated with significant morbidity and even mortality. We are the first to describe the technique of percutaneous thoracic nucleoplasty in three patients with severe radicular pain due to thoracic disc herniation. Two of the patients experienced more than 75% pain relief and one patient experienced more than 50% pain relief. Post-procedural pain relief was maintained up to an average of 10 months after nucleoplasty. One patient with preoperative neurological signs improved postoperatively. There were no reported complications in all three patients. In view of the reduced morbidity and shorter operating time, thoracic intervertebral disc nucleoplasty can be considered in patients with pain due to thoracic disc herniation, with no calcification of the herniated disc, and in patients who may be otherwise be unfit for conventional surgery.

Computed tomography and outcome in moderate and severe traumatic brain injury: hematoma volume and midline shift revisited.

Intracranial lesion volume and midline shift are powerful outcome predictors in moderate and severe traumatic brain injury (TBI), and therefore they are used in TBI and computed tomography (CT) classification schemes, like the Traumatic Coma Data Bank (TCDB) classification. In this study we aimed to explore the prognostic value of lesion volume and midline shift in moderate and severe TBI as measured from acute cranial CT scans. Also, we wanted to determine interrater reliability for the evaluation of these CT abnormalities. We included all consecutive moderate and severe TBI patients admitted to our hospital who were aged ≥16 years, over an 8-year period, as part of the prospective Radboud University Brain Injury Cohort Study. Six months post-trauma we assessed outcomes using the Glasgow Outcome Scale-Extended (GOS-E). We analyzed 605 patients and found an association of both lesion volume and midline shift with outcome; increases were associated with a higher frequency of patients with an unfavorable outcome or death. A cut-off value, such as that used in the TCDB CT classification (lesion volume 25 mL and midline shift 5 mm), was not found. The average interrater difference in volume measurement was 6.8 mL, and it was 0.2 mm for the determination of degree of shift. Using lesion volume and midline shift as continuous variables in prognostic models might be preferable over the use of threshold values, although an association of these variables with outcome in relation to other CT abnormalities was not tested. The data provided here will be useful for stratification of patients enrolled in clinical trials of neuroprotective therapies.

Near-normal gait pattern with peroneal electrical stimulation as a neuroprosthesis in the chronic phase of stroke: a case report.

In recent years, the use of functional electrical stimulation (FES) of the peroneal nerve has increased as an alternative for an ankle-foot orthosis (AFO) to treat stroke-related drop foot. We present a chronic stroke patient demonstrating an almost normal gait pattern with peroneal FES as a neuroprosthesis. A 60-year-old survivor of a right hemisphere infarction 21 months ago, who regularly used a polypropylene AFO, was provided with a surface-based peroneal FES device for severe drop foot. In a second instance, he received an implanted FES system because of skin problems with the surface stimulator. With both FES devices, the patient achieved an adequate foot elevation. Moreover, his hip and knee flexion angles during walking increased to normal values and his ankle push-off power increased. His gait pattern became almost symmetrical and less variable than with the AFO. Furthermore, his ability to avoid a sudden obstacle improved to normal values with FES. Our patient showed benefits from peroneal FES beyond what can be attributed to improved foot lift alone. With regard to the potential working mechanisms underlying this response to FES, biomechanical benefits related to improved ankle push-off are suggested as the main mechanism.

Long-term results of the neuroendoscopic management of colloid cysts of the third ventricle: a series of 90 cases.

BACKGROUND: The endoscopic removal of third ventricular colloid cysts has been developed as an alternative to microsurgical transcortical-transventricular and transcallosal approaches. OBJECTIVE: To examine the value of endoscopic technique by reviewing the large number of endoscopically treated patients with long-term follow-up in 2 neurosurgical centers. METHODS: A retrospective chart review was conducted for all patients admitted for resection of a third ventricular colloid cyst to the Radboud University Nijmegen Medical Centre (Nijmegen, The Netherlands) and the Hôpital Henri Mondor (Paris, France) between 1994 and 2007. Both clinical and radiological symptoms and operative results were evaluated. RESULTS: Postdischarge clinical follow-up was available for 85 patients over a mean period of 4 years 3 months. Permanent morbidity occurred in 1 patient (persisting preoperative memory deficit). Follow-up imaging of 80 evaluable patients showed that total or nearly total cyst removal was possible in 46 individuals (57.5%). Residual cyst was present in 34 patients (42.5%), and 6 required repeated endoscopic surgery for symptomatic regrowth. Recurrent cysts were mainly seen within the first 2 years after surgery. CONCLUSION: It is debatable whether the higher numbers of recurrent or residual cysts can be justified by the slightly lower complication rates achieved with endoscopic removal. However, results have been improving over the years. Moreover, the modifications observed on control magnetic resonance images justify the need for regular control imaging for at least the first 2 years postoperatively.

Prediction of the need for an MRI after surgical treatment of symptomatic lumbar herniated disc at discharge: evaluation of the necessity for regular visits at the outpatient clinic.

BACKGROUND: Surgical treatment of symptomatic lumbar disc herniations has been well established. The need for regular postoperative visits at the outpatient clinic has never been evaluated. In this study, factors predicting the need for magnetic resonance imaging, denoting an unfavorable outcome needing further evaluation, were evaluated. METHODS: The charts of all patients who underwent first surgery for a lumbar herniated disc were evaluated. Predefined factors that could possibly be a predictive factor were collected: gender, age at surgery, level of surgical pathology, profession of the patient, and at discharge: leg pain, back pain, medication used for leg pain, new neurological deficit after the surgical procedure, and the number of days of their postoperative stay at the hospital. The factors were statistically analyzed. RESULTS: One hundred seventy-two patients were identified. Twenty-nine patients underwent magnetic resonance imaging during their postoperative follow-up. None of the predefined factors at discharge had any predictive value. CONCLUSIONS: The need for a regular appointment at the outpatient clinic for patients who underwent the first surgery can be questioned. Preoperatively and postoperatively, extensive instructions about postoperative issues related to work and lifestyle should be given. By Web or telephone, these patients should complete questionnaires at regular intervals to evaluate to outcome of the surgery. In case of unsuspected events, persistent, or recurrent complaints the patient should visit the clinic or outpatient clinic.

Effect of electromagnetic-navigated shunt placement on failure rates: a prospective multicenter study.

OBJECT: As many as 40% of shunts fail in the first year, mainly due to proximal obstruction. The role of catheter position on failure rates has not been clearly demonstrated. The authors conducted a prospective cohort study of navigated shunt placement compared with standard blind shunt placement at 3 European centers to assess the effect on shunt failure rates. METHODS: All adult and pediatric patients undergoing de novo ventriculoperitoneal shunt placement were included (patients with slit ventricles were excluded). The first cohort underwent standard shunt placement using anatomical landmarks. All centers subsequently adopted electromagnetic (EM) navigation for routine shunt placements, forming the second cohort. Catheter position was graded on postoperative CT in both groups using a 3-point scale developed for this study: (1) optimal position free-floating in CSF; (2) touching choroid or ventricular wall; or (3) intraparenchymal. Episodes and type of shunt revision were recorded. Early shunt failure was defined as that occurring within 30 days of surgery. Patients with shunts were followed-up for 12 months in the standard group, for a median of 6 months in the EM-navigated group, or until shunt failure. RESULTS: A total of 75 patients were included in the study, 41 with standard shunts and 34 with EM-navigated shunts. Seventy-four percent of navigated shunts were Grade 1 compared with 37% of the standard shunts (p=0.001, chi-square test). There were no Grade 3 placements in the navigated group, but 8 in the standard group, and 75% of these failed. Early shunt failure occurred in 9 patients in the standard group and in 2 in the navigated group, reducing the early revision rate from 22 to 5.9% (p=0.048, Fisher exact test). Early shunt failures were due to proximal obstruction in 78% of standard shunts (7 of 9) and in 50% of EM-navigated shunts (1 of 2). CONCLUSIONS: Noninvasive EM image guidance in shunt surgery reduces poor shunt placement, resulting in a significant decrease in the early shunt revision rate.

The rationale of postoperative radiographs after cervical anterior discectomy with stand-alone cage for radicular pain.

OBJECT: Cervical anterior discectomy with stand-alone cage (CADC) placement is a known treatment for cervical radiculopathy due to a herniated intervertebral disc or an osteophyte. Routine radiographs are obtained at regular postoperative intervals, but the consequences of routinely obtained radiographs are not known. In this study, the authors evaluated whether postoperative plain radiographs influenced the medical or surgical treatment of patients who underwent CADC placement. METHODS: The charts and radiographs of all patients who underwent CADC placement in 2007 were retrieved and reviewed retrospectively. In addition, the charts and radiographs of 50 consecutive patients who were seen after a CADC was placed during a period in 2008 were studied prospectively. Special emphasis was given to any abnormalities seen on the radiographs and especially their influence on further treatment. RESULTS: The charts and radiographs of 82 patients were retrospectively examined. A total of 138 levels were addressed, and in the prospective series 75 levels were surgically treated. The subsidence rate in the retrospective series was 14.5%. In 1 patient a slight anteroposition of the cage was seen. None of the radiographic abnormalities were related to the outcome of the patient or contributed to a change in the patient's treatment. CONCLUSIONS: Routine radiographs after CADC placement are not warranted. Intraoperative verification of the position of the cage is recommended. Obtaining radiographs are only mandatory when signs or symptoms suggesting a postoperative complication are present. The authors propose a new algorithm for the follow-up of patients after CADC placement.

Should anterior pituitary function be tested during follow-up of all patients presenting at the emergency department because of traumatic brain injury?

CONTEXT: A wide range (15-56%) of prevalences of anterior pituitary insufficiency are reported in patients after traumatic brain injury (TBI). However, different study populations, study designs, and diagnostic procedures were used. No data are available on emergency-department-based cohorts of TBI patients. OBJECTIVE: To assess the prevalence of pituitary dysfunction in an emergency-department-based cohort of TBI patients using strict endocrinological diagnostic criteria. METHODS: Of all the patients presenting in the emergency department with TBI over a 2-year period, 516 matched the inclusion criteria. One hundred and seven patients (77 with mild TBI and 30 with moderate/severe TBI) agreed to participate. They were screened for anterior pituitary insufficiency by GHRH-arginine testing, evaluation of fasting morning hormone levels (cortisol, TSH, free thyroxine, FSH, LH, and 17beta-estradiol or testosterone), and menstrual history 3-30 months after TBI. Abnormal screening results were defined as low peak GH to GHRH-arginine, or low levels of any of the end-organ hormones with low or normal pituitary hormone levels. Patients with abnormal screening results were extensively evaluated, including additional hormone provocation tests (insulin tolerance test, ACTH stimulation test, and repeated GHRH-arginine test) and assessment of free testosterone levels. RESULTS: Screening results were abnormal in 15 of 107 patients. In a subsequent extensive endocrine evaluation, anterior pituitary dysfunction was diagnosed in only one patient (partial hypocortisolism). CONCLUSION: By applying strict diagnostic criteria to an emergency-department-based cohort of TBI patients, it was shown that anterior pituitary dysfunction is rare (<1%). Routine pituitary screening in unselected patients after TBI is unlikely to be cost-effective.

The status of the fourth ventricle and ambient cisterns predict outcome in moderate and severe traumatic brain injury.

Computed tomography (CT) of the head has become the diagnostic tool of choice, particularly for moderate and severe traumatic brain injury (TBI). Various CT characteristics are associated with outcome, and may therefore be used as outcome predictors. One of the most prominent predictors appears to be the status of the basal cisterns. This study describes the prognostic value of the appearance of individual cisterns and ventricles in relation to that of the basal cisterns. Further, we determine the interrater and intrarater reliability in the evaluation of the cisterns and ventricles. All consecutive moderate and severe adult TBI patients admitted to our hospital were included in this study as part of the prospective Radboud University Brain Injury Cohort Study (RUBICS). Outcome was assessed at 6 months post-trauma using the Glasgow Outcome Scale-Extended (GOS-E). The predictive value of cisterns and ventricles was determined using multivariate binary logistic regression analysis. We included 126 moderate and 574 severe TBI patients. Absence (complete obliteration), but also compression of the ambient cisterns and/or the fourth ventricle were strongly related to unfavorable outcome and death and emerged as the only significant outcome predictors after multivariate analysis. The assessment of the ambient cisterns and the fourth ventricle had a satisfactory inter- and intrarater reliability (kappa coefficients: 0.80-0.95). We conclude that, because obliteration of the ambient cisterns and the fourth ventricle both are better than the status of the basal cisterns as outcome predictors, they might be used in CT prediction models in cases of moderate and severe TBI.

A haemodialysis patient with back pain: brown tumour as a cause of spinal cord compression under cinacalcet therapy.

A 43-year-old haemodialysis patient was admitted to hospital because of paroxysmal pain in the upper abdominal region radiating to the back. Laboratory tests showed severe hyperparathyroidism [intact parathyroid hormone (iPTH) 69 pmol/L; reference range: 1.3-6.8 pmol/L], hypercalcaemia (2.79 mmol/L), hyperphosphataemia (1.6 mmol/L) and elevated serum total alkaline phosphatase (200 U/L). After developing a disturbed sensation and paraesthesia in both feet, epidural compression of the spinal cord was suspected. Magnetic resonance imaging showed a tumour that severely compressed the myelum of the thoracic spine. Histological investigation revealed a brown tumour or osteoclastoma, an erosive bony lesion caused by increased osteoclastic activity and peritrabecular fibrosis. A brown tumour is a benign tumour that is a rare complication of severe renal hyperparathyroidism. The brown tumour developed despite a 1-year treatment of the patient with cinacalcet, which, however, did not result in a major decrease in serum iPTH concentration (from 110 to 69 pmol/L: 37% reduction). Urgent decompressive neurosurgery and subtotal parathyroidectomy resulted in a complete recovery.

Outcome prediction in mild traumatic brain injury: age and clinical variables are stronger predictors than CT abnormalities.

Mild traumatic brain injury (mTBI) is a common heterogeneous neurological disorder with a wide range of possible clinical outcomes. Accurate prediction of outcome is desirable for optimal treatment. This study aimed both to identify the demographic, clinical, and computed tomographic (CT) characteristics associated with unfavorable outcome at 6 months after mTBI, and to design a prediction model for application in daily practice. All consecutive mTBI patients (Glasgow Coma Scale [GCS] score: 13-15) admitted to our hospital who were age 16 or older were included during an 8-year period as part of the prospective Radboud University Brain Injury Cohort Study (RUBICS). Outcome was assessed at 6 months post-trauma using the Glasgow Outcome Scale-Extended (GOSE), dichotomized into unfavorable (GOSE score 1-6) and favorable (GOSE score 7-8) outcome groups. The predictive value of several variables was determined using multivariate binary logistic regression analysis. We included 2784 mTBI patients and found CT abnormalities in 20.7% of the 1999 patients that underwent a head CT. Age, extracranial injuries, and day-of-injury alcohol intoxication proved to be the strongest outcome predictors. The presence of facial fractures and the number of hemorrhagic contusions emerged as CT predictors. Furthermore, we showed that the predictive value of a scheme based on a modified Injury Severity Score (ISS), alcohol intoxication, and age equalled the value of one that also included CT characteristics. In fact, it exceeded one that was based on CT characteristics alone. We conclude that, although valuable for the identification of the individual mTBI patient at risk for deterioration and eventual neurosurgical intervention, CT characteristics are imperfect predictors of outcome after mTBI.

The role of different imaging modalities: is MRI a conditio sine qua non for ETV?

OBJECTIVE: To describe the different imaging modalities used for the diagnosis and classification of hydrocephalus, their role in defining the optimal treatment of hydrocephalus and to define the optimal preoperative diagnostics for endoscopic third ventriculocisternostomy (ETV). METHODS: An overview on available imaging modalities for hydrocephalus will be given and their pros and cons discussed. In addition, different aspects of the treatment of hydrocephalus by shunts and by ETV will be highlighted. DISCUSSION: The role of the technical aspects of performing an ETV, the role of the surgeon's philosophy, the role of the urgency of the procedure, and the role of informed consent on the requirements for the imaging of the hydrocephalus will be discussed. CONCLUSION: The authors conclude that MRI is a conditio sine qua non for ETV in elective surgical cases.

Reduced work capacity after lumbar disc surgery: the role of cognitive-behavioral and work-related risk factors.

A significant number of patients who have had surgery for lumbosacral radicular syndrome still have a reduced work capacity several months later. In a prospective cohort study of 182 people who underwent lumbar disc surgery, we determined the predictive value of preoperatively measured cognitive-behavioral and work-related factors on work capacity 6 months after surgery. Logistic regression analyses indicated that these factors independently predicted work capacity 6 months after surgery. Specifically, fear of movement/(re)injury, more passive pain coping, and higher physical work-load predicted reduced work capacity in multiple logistic regression analyses, taking into account the role of a wide range of control variables including demographic variables, preoperative disability and pain intensity, neurological deficits, intake of analgesics, duration of complaints, and pain intensity 3 days postoperatively. The study supports the need to develop and evaluate preoperative risk screening measures that include both cognitive-behavioral and work-related factors and to evaluate the effectiveness of cognitive-behavioral and work-related interventions in patients at risk of reduced work capacity after surgery for LRS.

Continued disability and pain after lumbar disc surgery: the role of cognitive-behavioral factors.

Cognitive-behavioral factors are considered important in the development of chronic disability and pain in patients with low back pain. In a prospective cohort study of 277 patients undergoing surgery for lumbosacral radicular syndrome, the predictive value of preoperatively measured cognitive-behavioral factors (fear of movement/(re)injury, passive pain coping, and negative outcome expectancies) for disability and pain intensity at 6 weeks and 6 months after surgery was investigated, taking into account the effect of possible confounding variables. Higher levels of cognitive-behavioral factors were found to be associated with a worse outcome at both 6 weeks and 6 months. These associations remained significant after controlling for possible confounding variables (preoperative disability and pain intensity, age, gender, educational level, duration of complaints, neurological deficits, and intake of analgesics) and pain intensity 3 days postoperatively. In multiple regression analyses, the cognitive-behavioral factors independently predicted different outcomes. Fear of movement/(re)injury predicted more disability and more severe pain at 6 weeks and more severe pain at 6 months; passive pain-coping strategies predicted more disability at 6 months; and negative outcome expectancies predicted more disability and more severe pain at both 6 weeks and 6 months. The findings support the potential utility of preoperative screening measures that include cognitive-behavioral factors for predicting surgical outcome, as well as studies to examine the potential benefits of cognitive-behavioral treatment to improve surgical outcome.

Use of a tubular retractor system as a minimally invasive technique for epidural plate electrode placement under local anesthesia for spinal cord stimulation: technical note.

OBJECTIVE: To improve the technique of placement of large plate electrodes for spinal cord stimulation with a minimally invasive approach using the METRx tubular retractor system (Medtronic Sofamor Danek, Minneapolis, MN). This dilating system splits the paravertebral musculature, avoiding the need to strip these muscles from the spine. The technique described makes it possible to perform the procedure (currently, it is most frequently performed using general anesthesia) with local anesthesia and sedation, allowing test stimulation, and with little intraoperative or postoperative discomfort for the patient. METHODS: The tubular retractor system was used to approach the spine at the desired level using local anesthesia. A small laminectomy was performed through the working tube, and the plate electrodes were introduced by the same approach. Test stimulation could be performed to determine the correct electrode position because only local anesthesia was used. RESULTS: Seven patients were scheduled for placement of large plate electrodes for spinal cord stimulation. In six patients, with different indications for the placement of spinal cord stimulation, the electrode could be placed using the minimally invasive tubular retractor system approach with local anesthesia and slight sedation. A good test stimulation was obtained in all of the patients, resulting in good pain relief after definitive implantation. We were not able to perform the procedure in one patient because we could not reach the spinal canal at the level operated on previously. All patients experienced only acceptable postoperative back pain. CONCLUSION: Using a tubular retractor system, implantation of plate electrodes for spinal cord stimulation can be performed under local anesthesia with acceptable discomfort for the patient, making the approach of the spinal canal minimally invasive. This method allows test stimulation to assess the correct electrode position and results in less local postoperative discomfort because of the small-muscle splitting approach.