Recovery of Voice After Reconstruction of the Recurrent Laryngeal Nerve and Adjuvant Nimodipine.

BACKGROUND: Transection injury to the recurrent laryngeal nerve (RLN) has been associated with permanent vocal fold palsy, and treatment has been limited to voice therapy or local treatment of vocal folds. Microsurgical repair has been reported to induce a better function. The calcium channel antagonist nimodipine improves functional recovery after experimental nerve injury and also after cranial nerve injury in patients. This study aims to present voice outcome in patients who underwent repair of the RLN and received nimodipine during regeneration. METHODS: From 2002-2016, 19 patients were admitted to our center with complete unilateral injury to the RLN and underwent microsurgical repair of the RLN. After nerve repair, patients received nimodipine for 2-3 months. Laryngoscopy was performed repeatedly up to 14 months postoperatively. The Voice Handicap Index (VHI) was administered, and patients' maximum phonation time (MPT) was recorded during the follow-up. RESULTS: All patients recovered well after surgery, and nimodipine was well tolerated with no dropouts. None of the patients suffered from atrophy of the vocal fold, and some patients even showed a small ab/adduction of the vocal fold on the repaired side with laryngoscopy. During long-term follow-up (>3 years), VHI and MPT normalized, indicating a nearly complete recovery from unilateral RLN injury. CONCLUSIONS: In this cohort study, we report the results of the first 19 consecutive cases at our center subjected to reconstruction of the RLN and adjuvant nimodipine treatment. The outcome of the current strategy is encouraging and should be considered after iatrogenic RLN transection injuries.

Continuous glucose monitoring by intravenous microdialysis: influence of membrane length and dialysis flow rate.

BACKGROUND: The benefit of tight glucose control in the intensive care unit is controversial. Part of the debate is around the frequency of glucose measurements, and therefore, a continuous glucose monitoring system is needed. Previously, we have shown that intravenous microdialysis has the potential for this purpose but that the accuracy must be improved. The aim of this study was to investigate the effects of the microdialysis membrane length and the perfusion rate on improving the accuracy. METHODS: Two volunteer studies were performed, one comparing intravenous microdialysis catheters with different lengths (10 and 20 mm) and one comparing different perfusion rates (0.5, 1 and 2 µl/min) with plasma glucose reference levels. Median values of seven samples taken over 70-min periods were compared using Bland-Altman plots. RESULTS: When microdialysis membranes of 10 and 20 mm perfused at a rate of 1 µl/min were used, the differences with measured plasma glucose levels were 30% ± 21% and 14% ± 13%. In comparison, plasma glucose measured in two different veins gave a difference of 3% ± 3%. In the second study, the differences between measured plasma glucose and that estimated with a microdialysis membrane of 30 mm perfused at 0.5, 1 and 2 µl/min were 8% ± 7%, 25% ± 19% and 39% ± 28%. Bland-Altman analyses gave the best line of equality (-0.11 mM) and the lowest limits of agreement (1.13 and -1.35 mM) when using the 30-mm membrane perfused with 0.5 µl/min. CONCLUSION: The agreement of the intravenous microdialysis with plasma glucose levels improved significantly when increasing the microdialysis membrane length, and thereby the membrane area, and decreasing the perfusion rate.

Neurophysiological evaluation of segmental motor neuron function of the thoracic cord in chronic SCI.

STUDY DESIGN: Pilot study. OBJECTIVES: The aim of the study was to develop a neurophysiological method to diagnose the cranial as well as the caudal level of a complete thoracic spinal cord injury (SCI) with higher precision than today's protocols. SETTING: SCI unit Karolinska University Hospital, Stockholm, Sweden. METHODS: Bipolar needle electromyography was recorded in intercostal spaces of five patients with chronic, complete thoracic SCI. Tests were performed during rest, during voluntary activation and during activation of lower body spasticity. Magnetic resonance imaging (MRI) was performed in each patient according to a protocol optimized for imaging near metal implants. RESULTS: Three distinct patterns were found in each patient. Above the lesion we found voluntary activated, normal motor unit potentials (MUPs). At the neurological level and a varying number of segments below, denervated intercostal segments with fibrillation potentials and positive sharp waves appeared. Below the neurological level, normal MUP activated in concert with lower body spasticity was found. The number of denervated segments showed a significant correlation to the length of spinal cord discontinuity on MRI (r=0.97, P<0.05). CONCLUSION: Intercostal neurophysiology in combination with MRI optimized for imaging near metal implants can be used to determine the extent of a chronic complete thoracic SCI, both anatomically and functionally. The described method increases the sensitivity to detect delicate neurological changes related to the dynamic of the pathology that follows SCI and may be useful in analyzing outcome in clinical trials.

The optimal timing of baseline radiostereometric analysis of uncemented press fit cups.

BACKGROUND AND AIMS: The baseline radiostereometric analysis (RSA) is usually performed during the first postoperative week. We investigated the micromotion of two uncemented press fit acetabular cups during the first week after total hip arthroplasty. MATERIAL AND METHODS: All study patients had unilateral osteoarthritis of the hip and received an uncemented THA combination consisting of a CLS stem and either an Allofit or an Interop acetabular cup. The study group consisted of 24 patients who underwent RSA within 1 hour after skin closure, and at 1 and 7 days after surgery. RESULTS: The upper limit of the 95% confidence interval for micromotion was less than or close to the precision of the method for all studied directions during the first week after surgery. Mean values indicate proximal and medial translation of the uncemented cup at one week. CONCLUSIONS: We found only minimal micromotion, barely above the precision limit, measured as medial and proximal translations of these uncemented cups. This indicates that the first postoperative RSA measurement following a primary THA with an uncemented press fit ace-tabular cup should be made as early as possible after the first postoperative day.

Continuous glucose monitoring by intravenous microdialysis.

BACKGROUND: The conflicting results from studies over tight glucose control in intensive care unit (ICU) patients ask for a continuous on-line real-time glucose monitoring in future. Here, intravenous microdialysis was tested in ICU patients and healthy volunteers. Primary aims were technical feasibility and accuracy. METHODS: A microdialysis catheter was inserted into a peripheral vein. ICU patients (n=10) were studied for up to 5 days. Healthy volunteers (n=6) were studied on one occasion. Recordings were monitored during 70 min each 24-h period to allow for an estimate of variability over time. Microdialysis glucose and lactate were compared with plasma glucose and whole blood lactate. Results are presented as medians (quartiles) of the differences between microdialysis and plasma concentrations over each of the 70-min recording periods. RESULTS: Out of the included ICU patients, no exclusions or early terminations were due to failure of the microdialysis catheter. The concordance was highly variable. The difference of medians over the recording periods differed by -34% (-40, -16) in patients and -22% (-31, -15) for the volunteers. In contrast, the overall variability within the individual measurement periods was low. CONCLUSION: Technical feasibility was good, but the accuracy was not sufficient and the variability between the recording periods was high without calibrations. The non-availability of suitable peripheral veins was a problem in many patients screened but not included in the study. Intravenous microdialysis to obtain continuous on-line real-time glucose monitoring is technically feasible, but accuracy needs to be improved.

Sociodemographic differences in antiepileptic drug prescriptions to adult epilepsy patients.

BACKGROUND: According to the Swedish Health Care Act, patients should be provided with the health care they need, regardless of sociodemographic status. We investigated whether in Sweden sociodemographic differences are associated with access to expert health care and antiepileptic drug (AED) prescriptions in epilepsy. METHOD: Patients with epilepsy were identified in the National Patient Register. Persons >or=18 years on continuous AED treatment in 2006 were identified in the recently established Swedish Prescribed Drug Register. Data on sociodemographic variables were obtained from several other national registers. We linked data to examine whether epilepsy patients' access to neurologists and the prescription of individual AEDs are related to sex, age, educational level, area of residence, region of birth, or income. We also assessed whether AEDs are prescribed differently to patients with epilepsy by neurologists as compared to non-neurologists. RESULTS: We identified 26,124 epilepsy patients in the register who were on continuous AED treatment (effective sample). Being women, young, highly educated, having high incomes, and residing in a larger city meant being more often treated by a neurologist than by other specialists. The prescriptions of AEDs differed according to gender, age, education, place of residence, and income. Lamotrigine and levetiracetam were prescribed to a larger extent by a neurologist rather than by other specialists. CONCLUSIONS: This nationwide cross-sectional study of epilepsy patients indicates that sociodemographic characteristics are important for access to neurologists and prescriptions of individual antiepileptic drugs. Prospective studies using patient-related outcomes are needed to analyze the consequences of these differences.

Empirical evidence of underutilization of referrals for epilepsy surgery evaluation.

BACKGROUND: Epilepsy surgery is a treatment that can cure patients with intractable epilepsy. This study investigates whether referrals for epilepsy surgery evaluation are underutilized. METHODS: Patients with epilepsy aged 18-60 years were identified in a computerized registry held by public health care providers in a Swedish county using ICD codes. Clinical data and data on referral status for epilepsy surgery were obtained from the patients' medical records. Potential candidates for epilepsy surgery evaluation were identified using pre-specified criteria. Obstacles for referral were analysed by comparing clinical data in patients who were considered for referral and those who were not. Appropriateness of non-referral was evaluated against recommendations from the Swedish Council on Technology in Health Care (SBU). RESULTS: Of 378 patients with epilepsy in the registry, 251 agreed to participate. Of 251, 40 were already referred patients and 48 patients were identified as potential candidates for epilepsy surgery evaluation by study criteria. Referral had been considered but not performed in 15 of the potential candidates. Potential candidates not considered for referral were less likely to have seen a neurologist, to have had an EEG, CT and MRI, and more likely to have cognitive disturbances. Following the recommendations by the SBU, 28 of 48 potential candidates were identified as inappropriately not referred patients. CONCLUSION: The number of missed referrals for epilepsy surgery evaluation was estimated to be 60 per 100,000 inhabitants. Several important obstacles were found for not referring patients for epilepsy surgery evaluation.

Mammography-related breast pain is associated with migraine.

There is little information about the perception of experimentally induced extracephalic pain in migraine. This study investigates the associations between mammography-related pain and migraine. A neurologist clinically assessed 630 women aged 40-74 years attending a population-based breast cancer screening programme. Headache criteria proposed by the International Headache Society were used. Mammography-related pain was measured on a 100-mm visual analogue scale. High levels of mammography-related pain were associated with migraine. This association was related to mammographic examination during the early follicular phase and menopausal status, but unrelated to differences in age, compression pressure, education, current use of hormonal replacement therapy, anxiety, and recent use of analgesics and antimigraine medication. The results of the present study indicate that migraine and compression-induced breast pain are related.

Migraine headache and obesity in women aged 40-74 years: a population-based study.

This study investigates the associations between obesity and migraine. A neurologist clinically assessed 684 women aged 40-74 years attending a population-based mammography screening programme. Body height and weight were measured and body mass index (BMI) calculated. Obesity was defined as a BMI > or = 30 kg/m2. The proportion of obesity did not differ between women with active migraine, women with inactive migraine or women who had never experienced migraine (P = 0.96). The distribution of frequency, intensity, duration or severity of attacks did not differ between obese and non-obese women with migraine. In this study there were no significant associations between migraine or migraine characteristics on the one hand and obesity on the other.

A 3-year follow-up of headache diagnoses and symptoms in Swedish schoolchildren.

Information is sparse concerning the incidence and prognosis of headache in children from the general population, especially of tension-type headache. In this study, headache diagnoses and symptoms were reassessed in 122 out of 130 schoolchildren after 3 years. Nearly 80% of those with headache at first evaluation still reported headache at follow-up. Although the likelihood of experiencing the same headache diagnosis and symptoms was high, about one-fifth of children with tension-type headache developed migraine and vice versa. Female gender predicted migraine and frequent headache episodes predicted overall headache at follow-up. The estimated average annual incidence was 81 and 65 per 1000 children, for tension-type headache and migraine, respectively. We conclude that there is a considerable risk of developing and maintaining headache during childhood. Headache diagnoses should be reassessed regularly and treatment adjusted. Girls and children with frequent headache have a poorer prognosis and therefore intervention is particularly important in these groups.

Nimodipine and microsurgery induced recovery of the vocal cord after recurrent laryngeal nerve resection.

Transection of the recurrent laryngeal nerve leads to permanent palsy of the vocal cord. Experimental studies have confirmed that nimodipine increases the pace of axonal regeneration. We present a case of a 19-year-old male, suffering a thyroid cancer disease, who was subjected to unilateral resection of the recurrent laryngeal nerve during surgery. The nerve was repaired with a nerve graft and the patient further treated with nimodipine for 3 months. Evaluation of the patient showed normalization of voice, movement of the vocal cord on the injured side, and electromyography evidence of reinnervation of the larynx muscles at 15 months after surgery.

Resorbable cement for the augmentation of internally-fixed unstable trochanteric fractures. A prospective, randomised multicentre study.

We undertook a multicentre, prospective study of a series of 112 unstable trochanteric fractures in order to evaluate if internal fixation with a sliding screw device combined with augmentation using a calcium phosphate degradable cement (Norian SRS) could improve the clinical, functional and radiological outcome when compared with fractures treated with a sliding screw device alone. Pain, activities of daily living, health status (SF-36), the strength of the hip abductor muscles and radiological outcome were analysed. Six weeks after surgery, the patients in the augmented group had significantly lower global and functional pain scores (p < 0.003), less pain after walking 50 feet (p < 0.01), and a better return to the activities of daily living (p < 0.05). At follow-up at six weeks and six months, those in the augmented group showed a significant improvement compared with the control group in the SF-36 score. No other significant differences were found between the groups. We conclude that augmentation with calcium phosphate cement in unstable trochanteric fractures provides a modest reduction in pain and a slight improvement in the quality of life during the course of healing when compared with conventional fixation with a sliding screw device alone.

Neuronal survival and glial reactions after recurrent laryngeal nerve resection in the rat.

OBJECTIVES/HYPOTHESIS: Complete axonal injury to the recurrent laryngeal nerve (RLN) leads to permanent loss of coordinated function of the intrinsic muscles of the larynx. The aim of the present study was to investigate retrograde reactions, neuronal survival, and glial reactions in the nucleus ambiguus after a distal resection of the RLN to evaluate the potential need for neuroprotective substances. STUDY DESIGN AND METHODS: A segment of the left RLN was resected in 31 adult rats. Before sacrifice of the animals at 2 to 28 days postlesion, the motor neurons in the nucleus ambiguus were retrogradely traced by the use of Fluorogold. Brainstems were isolated and processed for neuron quantification and immunohistochemical analysis. Neuron counts were performed in the nucleus ambiguus on serial sections. Glial reactions were investigated in the nucleus ambiguus using immunohistochemistry. RESULTS: No decrease in the number of motor neurons in the nucleus ambiguus could be demonstrated up to 1 month postlesion. Astroglia and microglia showed increased immunoreactivity at 7 to 14 days postinjury, followed by a slight decline in glial reaction. Microglia revealed no signs of transformation into macrophages during the study period, further indicating the absence of neuronal loss. CONCLUSIONS: Neuronal death does not occur within 1 month postlesion as a result of resection of the RLN in the adult rat, and neuroprotective substances should therefore be of minor value after RLN injury. Glial reactions appear in a similar fashion as after other peripheral nerve lesions not causing neuronal loss.

The ALS/MND prevalence in Sweden estimated by riluzole sales statistics.

OBJECTIVES: To determine whether sales statistics for riluzole can be used as a marker for the prevalence of amyotrophic lateral sclerosis (ALS)/motor neuron disease (MND) in Sweden. MATERIALS AND METHODS: A questionnaire was sent to all neurological units in Sweden asking about the numbers of patients with ALS/MND and whether these patients were treated with riluzole. Sales statistics for riluzole were obtained from the 906 public pharmacies and 89 hospital pharmacies in Sweden. RESULTS: Eighty percent of the neurological units answered the questionnaire. The estimated prevalence in September 2003 from the questionnaire was 5.4/100,000 inhabitants. The sales expressed in defined daily dose/100,000 inhabitants/day was 3.8. For the counties the correlation between these two parameters was 0.83. CONCLUSION: Estimated prevalence is highly correlated with sales statistics for riluzole. Riluzole sales statistics could be used as a crude marker for the prevalence of ALS/MND in Sweden.

Unstable trochanteric fractures augmented with calcium phosphate cement. A prospective randomized study using radiostereometry to measure fracture stability.

BACKGROUND AND AIMS: Internally fixed unstable trochanteric fractures might be difficult to retain in position during healing. Secondary displacement might lead to malunion and poor functional result. The aim with this study was to measure whether augmentation with resorbable calcium-phosphate cement could improve fracture stability as shown in biomechanical studies. MATERIAL AND METHODS: 26 ambulatory patients with an unstable trochanteric fracture were randomized to treatment with a sliding screw device alone (Controls) or the same device combined with calcium-phosphate cement for augmentation (Augmented). All patients were allowed unrestricted weight bearing after surgery. Fracture movement was measured with radiostereometry (RSA) at 1 and 6 weeks and at 6 months. RESULTS: Two patients died during the study period due to unrelated causes and another three were excluded due to technical problems with the RSA in two and concomitant illness in one. 21 patients (11 Augmented and 10 Controls) were followed according to the study protocol. At 1 week the augmented fractures had moved on average 1.9+/-1.7 mm while movement in the controls was 4.0+/-2.4 mm (p < 0.05). The average total movement from the day after surgery until 6 months, when all fractures had healed, was 7.8+/-6.2 mm for the augmented fractures and 13.2+/-4.3 mm for the controls (p < 0.05). Varus angulation was the most pronounced rotational movement for both groups although augmented fractures revealed less varus angulation compared with controls at all time points. Rotation around the longitudinal and transversal axes were small with no significant differences between treatment groups. CONCLUSION: Augmentation with calcium-phosphate cement improved the stability of unstable trochanteric fractures fixed with a sliding screw device. The improvement was most pronounced for varus angulation and lateral and distal migration of the head and neck fragment.

Stability of cemented all-polyethylene keeled glenoid components. A radiostereometric study with a two-year follow-up.

We studied the stability of cemented all-polyethylene keeled glenoid components by radiostereometric analysis (RSA) in 16 shoulders which had received a total shoulder replacement. There were 14 women (one bilateral) and one man with a mean age of 64 years. The diagnosis was osteoarthritis in eight and rheumatoid arthritis in seven. Two of the shoulders were excluded from the RSA study because of loosening of the tantalum markers. Three tantalum markers were inserted in the glenoid socket, two in the coracoid process and two in the acromion. The polyethylene keeled glenoid component was marked with three to five tantalum markers. Conventional radiological and RSA examinations were carried out at five to seven days, at four months and at one and two years after operation. Radiolucent lines were found in all except three shoulders. Migration was most pronounced in the distal direction and exceeded 1 mm in four shoulders. In ten shoulders rotation exceeded 2 degrees in one or more axes with retroversion/anteversion being most common. No correlation was found between migration and the presence of radiolucencies on conventional radiographs.

Stability of internally fixed femoral neck fractures augmented with resorbable cement. A prospective randomized study using radiostereometry.

BACKGROUND AND AIMS: Internal fixation of displaced femoral neck fractures is associated with a high risk for complications such as non-union or avascular necrosis. A stable fracture fixation can improve prognosis although stability is often counteracted by weak osteoporotic bone. The aim with this study was to evaluate whether augmentation with resorbable calcium-phosphate cement could improve fracture stability during the early period after surgery as shown in biomechanical studies. MATERIAL AND METHODS: 40 ambulatory patients with a displaced femoral neck fracture were randomized to treatment with cannulated screws alone (controls) or screws combined with calcium-phosphate cement for augmentation (augmented). All patients were allowed unrestricted weight bearing after surgery. Fracture movement was measured with radiostereometry (RSA) at 1 and 6 weeks. RESULTS: At 1 week the augmented fractures had moved on average 1.9 +/- 1.0 mm while movement in the controls was 5.5 +/- 3.4 mm (p < 0.0001). The average total movement at 6 weeks was 6.9 +/- 2.9 mm and 10.9 +/- 5.1 mm, respectively (p < 0.005). Varus angulation and distal migration of the femoral head were the most common movements for both groups although augmented fractures had moved significantly less at both 1 and 6 weeks. There were no significant differences in angulation between groups around the longitudinal and transversal axes or in migration along the transverse or sagittal axes. CONCLUSION: Augmentation with calcium-phosphate cement improved the stability of internally fixed femoral neck fractures during the first six weeks after surgery, with improvement being less pronounced at six weeks compared with at one week.

Placebo response in clinical randomized trials of analgesics in migraine.

The objective was to assess the placebo response in randomized clinical trials of analgesics in the treatment of migraine attacks. We included placebo-controlled studies that used the criteria of the International Headache Society for the diagnosis of migraine and headache response as the primary efficacy parameter. In the 11 studies that qualified for inclusion, headache response occurred after placebo treatment in 7-50% of the migraineurs with an average placebo response rate of 30% (95% confidence interval (CI) 23-36). Two hours after treatment with placebo an average of 9% (95% CI 7-12, range 7-17%) of the patients were found to be pain free. In conclusion, the average headache response rate to placebo was 30% in randomized clinical trials of analgesics in migraine with a tremendous variation among studies. Placebo response rates vary with the choice of primary efficacy measure as well as patient characteristics and study design.