Cognitive and functional impairments in ischemic stroke patients with concurrent small vessel and large artery disease.

BACKGROUND AND PURPOSE: Concurrent small vessel, intracranial and extracranial large artery disease (SLAD) is common in Asian but its impact on cognitive and functional outcomes is unclear. We aimed to evaluate the clinical, cognitive and functional outcomes in ischemic stroke patients with SLAD. METHODS: Chinese ischemic stroke patients with diffuse white matter lesions (WMLs) were recruited as part of the VITATOPS Trial. They were studied with MRI and MRA of brain. Various neuropsychiatric batteries were used to assess the cognitive functions. RESULTS: Totally 97 patients with acute ischemic stroke and diffuse WMLs were included, of whom 44 (45%) had SLAD. Patients with SLAD had lower Mini Mental State Examination (MMSE) when compared with the patients without SLAD. They had more behavioral symptoms and caused more stress in caregivers as assessed by the Neuropsychiatric Inventory (NPI). Multivariate regression analysis showed SLAD contributed significantly to MMSE, NPI Patient (NPI P) and NPI Care Giver (NPI CG). Among 44 patients with SLAD, 30 (68%) had severe cognitive impairment. They were older and less educated. They had more diabetes and poorer performance in neuropsychiatric tests including Mattis Dementia Rating Scale Initiation/Perseveration subset (MDRS I/P) and Clinical Dementia Rating (CDR). They also had poorer functional outcomes as assessed by Barthel Index (BI) and Instrumental activities of daily living (IADL). CONCLUSIONS: This was the first MRA-based study to take into consideration the clinical, cognitive and functional outcomes in ischemic stroke patients with SLAD. Patients with SLAD had poorer cognitive and functional outcomes when compared to patients without SLAD.

Gabapentin for the treatment of carpal tunnel syndrome: a randomized controlled trial.

OBJECTIVE: Based on its efficacy in treating neuropathic pain, gabapentin may be effective for the treatment of carpal tunnel syndrome (CTS). The purpose of this study was to evaluate the efficacy of gabapentin for symptom relief in CTS. METHODS: We conducted a randomized, double-blinded, placebo-controlled trial recruiting patients with newly diagnosed idiopathic CTS of more than a period of three months. Diagnosis was based on characteristic symptoms with electrophysiological confirmation. Patients were randomly assigned to an active group receiving gabapentin (starting dose 300 mg once daily to a target of 900 mg daily) or a placebo group. Primary end-point was the global symptom score (GSS), which was measured at baseline, two, and eight weeks. RESULTS: There was no significant difference in baseline variables between the two treatment groups. Hundred and forty patients were enrolled in the study, of whom 71 were randomly assigned to gabapentin group and 69 assigned to placebo group. Both gabapentin and placebo produced significant improvement in symptoms at two and eight weeks. The GSS at 2 and 8 weeks was 16.4 (SD 9.4) and 13.4 (SD 9.7), respectively, in the active group versus 14.9 (SD 9.0) and 12.5 (SD 8.9) in the control group (P < 0.01). But by eight weeks, the mean reduction in symptom severity of patients on gabapentin [-10.4 (SD 10.8)] was not significant when compared with placebo [-8.7 (SD 8.1), P < 0.39]. Adverse events were not severe and included dizziness, somnolence, and headache. CONCLUSIONS: Gabapentin did not produce a significant reduction in symptom severity compared with placebo over an eight-week period.

Vigabatrin-induced visual dysfunction in Chinese patients with refractory epilepsy.

PURPOSE: Bilateral visual field constriction has been reported following the use of the antiepileptic drug (AED) vigabatrin. The incidence of retinal toxicity is variable and there are limited data in Asian populations. The authors report the results of ophthalmologic examination in Chinese patients taking this drug. METHODS: The authors identified two groups of patients with refractory epilepsy: one group on vigabatrin and another cohort of patients taking other AEDs. The authors recorded the medical history and performed visual acuity testing, intraocular pressure measurement, slit lamp biomicroscopy, and conventional automated perimetry with Humphrey Visual Field Analyzer II in all patients. RESULTS: Eighteen patients--8 men and 10 women--with a mean age of 23.8 years who were taking vigabatrin were reviewed. Length of treatment with this drug ranged from 13 months to 5 years and the mean daily dosage was 1581 mg. None of the patients in either group had a history of coexisting optic nerve diseases or other neurotoxic drug use. Twenty of 36 (55.6%) eyes of the vigabatrin users showed significant bilateral visual field defects with 80% showing a concentric pattern, compared with none in the control group. CONCLUSIONS: The authors confirmed a high prevalence of visual field constriction associated with vigabatrin in Chinese patients. The use of alternative novel techniques such as measurement of the retinal nerve fibre layer thickness and perimetry may detect early retinal damage and result in even higher incidences. Visual field monitoring is recommended in patients who continue to take this drug.

Agreement between initial and final diagnosis of first seizures, epilepsy and non-epileptic events: a prospective study.

BACKGROUND: Differentiating between first seizure, epilepsy and a non-epileptic event is a challenging clinical exercise for many physicians as it may lead to different therapeutic implications. This study aims to investigate the agreement between the initial diagnosis at the accident and emergency (A&E) department and the final diagnosis following inpatient neurological evaluation of seizure disorders. METHOD: A prospective observational study between April 2004 and June 2005 in a regional hospital in Hong Kong recruited 1701 patients from the A&E to neurology/medical wards with initial diagnoses/labels matching any one of 12 predefined keywords which were categorised as either "seizure specific" or "non-specific". RESULTS: Among the 1170 patients with "non-specific" initial diagnoses/labels, 58 (5%) were finally diagnosed as having had a first seizure or epilepsy. Among 531 patients with "seizure specific" initial diagnoses/labels, 27 (5.1%) were subsequently diagnosed as having had non-epileptic events. The kappa value for agreement between the initial and final diagnosis was 0.88. Of the 154 patients with a final diagnosis of first seizure, 34 (22%) had "non-specific" initial labels. Among these patients, components of the evaluation contributing to revision of diagnosis included retrieval of witness accounts (47%), epileptiform discharges on EEG (47%), short term monitoring in patients suspected of acute symptomatic seizures (28%) and panel discussion of cases (22%). CONCLUSION: There was generally a high degree of agreement between the initial and final diagnosis, but first seizures were often missed initially. Careful history taking, judicious use of EEG, selective short term monitoring and liaison with specialists are important in reaching an accurate diagnosis.

Warfarin overdose due to the possible effects of Lycium barbarum L.

We reported an 80-year-old Chinese woman on chronic stable dose of warfarin who experienced two episodes of an elevated international normalized ratio (INR) after drinking herbal tea containing Lycium barbarum L. Our case illustrated the potential herbal-drug interaction between warfarin and L. barbarum L. in keeping with a previous case report. Enquiry about herbal intake may be a crucial part in the management of anticoagulation in this locality.

Incidence of deep-vein thrombosis in patients with fractures of the ankle treated in a plaster cast.

Stable fractures of the ankle can be successfully treated non-operatively by a below-knee plaster cast. In some centres, patients with this injury are routinely administered low-molecular-weight heparin, to reduce the risk of deep-vein thrombosis (DVT). We have assessed the incidence of DVT in 100 patients in the absence of any thromboprophylaxis. A colour Doppler duplex ultrasound scan was done at the time of the removal of the cast. Five patients did develop DVT, though none had clinical signs suggestive of it. One case involved the femoral and another the popliteal vein. No patient developed pulmonary embolism. As the incidence of DVT after ankle fractures is low, we do not recommend routine thromboprophylaxis.

Biomechanical testing of the locking compression plate: when does the distance between bone and implant significantly reduce construct stability?

AIM: To investigate in vitro the mechanical stability of a locking compression plate (LCP) construct in a simulated diaphyseal fracture of the humerus at increasing distances between the plate and bone. MATERIALS AND METHOD: A series of biomechanical in vitro experiments were performed using composite humerus sawbone as the bone model. Osteotomy created in the mid-diaphyseal region. A 10mm osteotomy gap was bridged with a seven-hole 4.5 stainless steel plate with one of four methods: a control group consisted of a dynamic compression plate applied flush to the bone and three study groups which comprised of a LCP applied flush to the bone, at 2mm and at 5mm from the bone. Standard AO technique used with locking head screws used for LCP fixation. Static and dynamic loading tests performed in a custom made jig in which the bone model was fixed both proximally and distally. Samples were subjected to cyclical compression, compression load to failure, cyclical torque and torque to failure. Plastic deformation and failure was assessed using three-dimensional measurements. Scanning electron microscopy of the plate and screw surface allowed detailed inspection of micro-fracture in areas of fatigue. RESULTS: Comparable results were achieved in both the DCP and LCP constructs in which the plate was applied at or less than 2mm from the bone. When applied 5mm from the bone the LCP demonstrated significantly increased plastic deformation during cyclical compression and required lower loads to induce construct failure. CONCLUSION: At a distance 5 mm we observe an inferior performance in the mechanical properties of the LCP construct with decrease in axial stiffness and torsional rigidity. If it is desirable for an LCP to be used the distance between plate and bone should be

The knee skyline radiograph: its usefulness in the diagnosis of patello-femoral osteoarthritis.

The aim of this study was to determine the usefulness of the skyline radiograph in the diagnosis of patellofemoral osteoarthritis. Additionally, we wanted to assess the usefulness of patello-femoral crepitus as a clinical sign of this condition. Seventy-seven patients scheduled to undergo knee surgery had standard antero-posterior, lateral and skyline X-rays of their affected knee. The presence of clinical patello-femoral crepitus was also documented preoperatively. At the operation, their patellofemoral joints were graded into two groups according to the presence or absence of osteoarthritis. The lateral and skyline view X-rays as well as patello-femoral crepitus were compared individually against the operative findings. The skyline view had a sensitivity of 79% and a specificity of 80%. The lateral view had a sensitivity of 82% and specificity of 65%. Patello-femoral crepitus as a sign had a sensitivity of 89% and a specificity of 82%. There was no statistically significant difference between the two radiological views in terms of sensitivity and specificity in the diagnosis of patellofemoral osteoarthritis. Hence, we cannot recommend the skyline view as a routine radiological investigation in all cases of suspected patellofemoral osteoarthritis.

Preoperative radiotherapy for soft tissue sarcoma: the Peter MacCallum Cancer Centre experience.

AIM: Radiotherapy has been shown to improve local control in combination with limb-sparing or conservative surgery in the management of localised soft tissue sarcoma. Our centre's treatment protocol is to offer preoperative external beam radiotherapy (50.4Gy in 28 fractions) followed by surgery four to six weeks later. The aim of this study is to review the treatment outcome and toxicity of patients treated with this protocol. METHODS: Consecutive patients with localised extremity or truncal soft tissue sarcoma who presented between January 1996 and December 2000 and treated with preoperative radiotherapy followed by limb-sparing surgery were reviewed. Patients with recurrent disease or metastatic disease at diagnosis and patients below the age of 16years were excluded. Local and distant recurrence, overall survival and treatment toxicity were analyzed. RESULTS: Sixty-seven cases were identified (41 males and 26 females). The median age was 52years (range 17 to 82). The majority (79%) had tumours located in the lower limb. The most common histological diagnoses were malignant fibrous histiocytoma and liposarcoma. The median follow-up was 4.1years (range 0.6 to 6.9). There were six local recurrences, two of which were successfully salvaged. Twenty patients developed distant metastases. The estimated 5-year actuarial local recurrence free, distant recurrence free and overall survival were 93%, 68% and 73% respectively. Acute radiotherapy toxicity and wound complications were acceptable and late toxicity was uncommon. CONCLUSION: Preoperative radiotherapy followed by surgery provides effective local control in the management of soft tissue sarcoma.

Single vs. two steroid injections for carpal tunnel syndrome: a randomised clinical trial.

We investigated the efficacy of a single vs. double steroid injections in the treatment of carpal tunnel syndrome (CTS) in a randomised double-blind controlled trial. Patients with idiopathic CTS were randomised into (i) one group receiving a baseline methylprednisolone acetate injection plus a saline injection 8 weeks later and (ii) a second group receiving methylprednisolone acetate injection at baseline and at 8 weeks. The primary outcome was the Global Symptom Score (GSS). Forty patients were recruited. By 40 weeks, the mean GSS improved from 25.6 to 14.1 in the single-injection group whereas from 26.7 to 12.6 in the reinjection group, but there was no significant difference in GSS between the two groups (p = 0.26). There were also no significant differences in terms of electrophysiological and functional outcomes. The results suggest that an additional steroid injection confers no added benefit to a single injection in terms of symptom relief.

Neurotoxicity induced by beta-lactam antibiotics: from bench to bedside.

Central nervous system toxicity following administration of beta-lactam antibiotics, of which penicillin is the prototype, is a potential cause of morbidity and mortality. In recent years, important advances have been made in the pathogenesis of antibiotic-related neurotoxicity. This review focuses on the experimental and clinical aspects of neurotoxicity caused by beta-lactam antibiotics. The purpose is to provide an update on the pathogenesis, mechanism, and clinical manifestations of the neurotoxicity, along with an overview of the relationship between antibiotic structure and convulsive action. In particular, some of the prevailing ideas about pathogenesis are highlighted, including theories of the mechanism of pathogenicity. A better understanding of antibiotic-related neurotoxicity, as derived from animal models and human clinical experience, would be of value in facilitating more efficient and safer use of antimicrobial compounds.

Bacterial meningitis in Hong Kong: 10-years' experience.

OBJECTIVE: We studied the etiology, clinical features and outcome of patients with bacterial meningitis from an urban Chinese city over a 10-years period. METHODS: We reviewed the files of all persons aged 15-years old or above diagnosed with community-acquired bacterial meningitis from a regional hospital. The clinical findings, relevant laboratory and imaging results as well as outcome were recorded in cases with microbiological evidence of meningitis. Neurosurgical and pediatric patients were excluded. RESULTS: Sixty-five patients between the ages of 15 and 86 years of age (mean 52 years) were identified of whom 18 (28%) died. The four most common causes were Mycobacteria tuberculosis (46%), Streptococcus pneumoniae (11%), Streptococcus suis (9%) and Klebsiella pneumoniae (8%). Neisseria meningitidis and Haemophilus influenzae were rare pathogens. The annual incidence of community-acquired bacterial meningitis was 1.27/100,000 adults. Delay in treatment was associated with a poorer prognosis (p<0.001, OR=38.84, CI=7.33-205.80). CONCLUSION: The causative organisms found in this region of China differ from that reported from Europe and the US; tuberculous meningitis is the most common cause of bacterial meningitis.

A randomized controlled trial of surgery vs steroid injection for carpal tunnel syndrome.

BACKGROUND: Decompressive surgery and steroid injection are widely used forms of treatment for carpal tunnel syndrome (CTS) but there is no consensus on their effectiveness in comparison to each other. The authors evaluated the efficacy of surgery vs steroid injection in relieving symptoms in patients with CTS. METHODS: The authors conducted a randomized, single blind, controlled trial. Fifty patients with electrophysiologically confirmed idiopathic CTS were randomized and assigned to open carpal tunnel release (25 patients) or to a single injection of steroid (25 patients). Patients were followed up at 6 and 20 weeks. The primary outcome was symptom relief in terms of the Global Symptom Score (GSS), which rates symptoms on a scale of 0 (no symptoms) to 50 (most severe). Nerve conduction studies and grip strength measurements were used as secondary outcome assessments. RESULTS: At 20 weeks after randomization, patients who underwent surgery had greater symptomatic improvement than those who were injected. The mean improvement in GSS after 20 weeks was 24.2 (SD 11.0) in the surgery group vs 8.7 (SD 13.0) in the injection group (p < 0.001); surgical decompression also resulted in greater improvement in median nerve distal motor latencies and sensory nerve conduction velocity. Mean grip strength in the surgical group was reduced by 1.7 kg (SD 5.1) compared with a gain of 2.4 kg (SD 5.5) in the injection group. CONCLUSION: Compared with steroid injection, open carpal tunnel release resulted in better symptomatic and neurophysiologic outcome but not grip strength in patients with idiopathic carpal tunnel syndrome over a 20-week period.

Thoracic penetration following mid-shaft clavicular fracture.

We describe a patient who sustained a widely displaced, high-energy, mid-shaft clavicular fracture in association with brachial plexus damage. The distal fragment was subsequently found to have penetrated the thoracic cavity. We describe the treatment of this rare injury with a successful outcome.