Anil T. Ahuja

Low-Molecular-Weight Heparin for the Treatment of Acute Ischemic Stroke

Background Despite doubts about their efficacy and concern about their safety, antithrombotic agents are often used to treat acute ischemic stroke. Recent experience in patients with other thromboembolic disorders suggests that low-molecular-weight heparin, which requires only subcutaneous administration once or twice daily, may be more effective and safer than standard (unfractionated) heparin. Methods We conducted a randomized, double-blind, placebo-controlled trial comparing two dosages of low-molecular-weight heparin with placebo in the treatment of ischemic stroke. Patients were randomly assigned within 48 hours of the onset of symptoms to receive high-dose nadroparin (4100 anti–factor Xa IU twice daily), low-dose nadroparin (4100 IU once daily), or placebo subcutaneously for 10 days. The primary measure of outcome was death or dependency regarding activities of daily living six months after randomization. Secondary outcomes were death, hemorrhagic transformation of the infarction, and other complica...

Randomized Phase II Trial of Concurrent Cisplatin-Radiotherapy With or Without Neoadjuvant Docetaxel and Cisplatin in Advanced Nasopharyngeal Carcinoma

PURPOSE To compare the toxicities, tumor control, survival, and quality of life of nasopharyngeal cancer (NPC) patients treated with sequential neoadjuvant chemotherapy followed by concurrent cisplatin-radiotherapy (CRT) or CRT alone. PATIENTS AND METHODS Previously untreated stage III to IVB NPC were randomly assigned to (1) neoadjuvant docetaxel 75 mg/m(2) and cisplatin 75 mg/m(2) every 3 weeks for two cycles, followed by cisplatin 40 mg/m(2)/wk concurrent with radiotherapy, or (2) CRT alone. Planned accrual was 30 patients per arm to detect 20% difference of toxicities based on 95% CIs. RESULTS From November 2002 to November 2004, 65 eligible patients were randomly assigned to neoadjuvant chemotherapy followed by CRT (n = 34) or CRT alone (n = 31). There was a high rate of grade 3/4 neutropenia (97%) but not neutropenic fever (12%) during neoadjuvant chemotherapy. No significant differences in rates of acute toxicities were observed between the two arms during CRT. Dose intensities of concurrent cisplatin, late RT toxicities and quality of life scores were comparable in both arms. The 3-year progression-free survival for neoadjuvant versus control arm was 88.2% and 59.5% (hazard ratio = 0.49; 95% CI, 0.20 to 1.19; P = .12). The 3-year overall survival for neoadjuvant versus control arm was 94.1% and 67.7% (hazard ratio = 0.24; 95% CI, 0.078 to 0.73; P = .012). CONCLUSION Neoadjuvant docetaxel-cisplatin followed by CRT was well tolerated with a manageable toxicity profile that allowed subsequent delivery of full-dose CRT. Preliminary results suggested a positive impact on survival. A phase III study to definitively test this neoadjuvant-concurrent strategy is warranted.

Use of Transcranial Doppler Ultrasound to Predict Outcome in Patients With Intracranial Large-Artery Occlusive Disease

Background and Purpose Intracranial large-artery occlusive disease is the predominant vascular lesion found in stroke patients of Asian, African, and Hispanic ancestry, making it numerically perhaps the most common vascular cause of stroke in the world. Relatively little is known about the clinical significance of finding such lesions. We investigate whether the presence and the extent of these vascular lesions help predict outcome after stroke. Methods On the basis of transcranial Doppler of the intracranial arteries with supplementary duplex ultrasound of the carotid arteries, we determined the number of occlusive arteries in the craniocervical circulation of consecutive patients who were hospitalized for acute cerebral ischemia. Patients were followed for 6 months for further vascular events (including transient ischemic attack, stroke, and acute coronary syndrome) or death. Results Among 705 consecutive Chinese patients studied, occlusive arteries were found in 345 patients (49%): 258 patients (37%) had intracranial lesions only, 71 (10%) had both extracranial and intracranial lesions, and 16 (2.3%) had extracranial lesions only. Sixty-three (18%) of the 345 patients with occlusive arteries and 35 (9.7%) of the 360 patients without occlusive arteries had further vascular event or death within 6 months. The risk of vascular events or death increased rapidly with rising numbers of occlusive arteries, after adjustment for vascular risk factors and stroke severity (adjusted odds ratio [OR] 1.25 per occlusive artery, 95% CI 1.12 to 1.39). Other independent risk factors included age (OR 1.03 per year of age, 95% CI 1.01 to 1.05) and atrial fibrillation (OR 3.00, 95% CI 1.40 to 6.69). Conclusions In patients with predominantly intracranial large-artery occlusive disease, the presence and the total number of occlusive arteries in the craniocervical circulation predict further vascular events or death within 6 months after stroke. Transcranial Doppler ultrasound is an important investigation for the evaluation of patients with stroke in populations at risk of intracranial atherosclerotic disease.

Modified Pfirrmann grading system for lumbar intervertebral disc degeneration.

Study Design. A reliability study was conducted. Objective. To modify a grading system for lumbar disc degeneration and to test the reliability of this modified grading system. Summary of Background Data. The 5-level Pfirrmann grading system for disc degeneration did not prove discriminatory when used to assess disc degeneration in the elderly spine. Such discriminatory power is necessary to test the association between other variables and severity of disc degeneration. Methods. An 8-level modified grading system for lumbar disc degeneration was developed including a description of the changes expected for each grade and a 24-image reference panel. The reliability of the modified grading system was tested on 260 lumbar intervertebral discs in 52 subjects (26 men, 26 female) with a mean age of 73 years (range, 67–83 years). All examinations were analyzed independently by 3 readers. Intraobserver and interobserver reliabilities were assessed by calculating weighted kappa statistics. Results. On average, for all 3 readers, 0.39% of the 260 discs were classified as Grade 2, 22% were classified as Grade 3, 21.5% were classified as Grade 4, 25.3% were classified as Grade 5, 19.1% were classified as Grade 6, 7.1% were classified as Grade 7, and 4.8% were classified as Grade 8. Intraobserver agreement was excellent (weighted kappa range, 0.79–0.91) with substantial interobserver agreement (weighted kappa range, 0.65–0.67). Complete intraobserver agreement was obtained, on average, in 85% of all discs with 84% of disagreement being as a result of a 1 grade difference. Complete interobserver agreement was obtained, on average, in 66% of all discs with 91% of disagreement being as a result of a 1 grade difference. Conclusion. The modified Pfirrmann grading system is useful at discriminating severity of disc degeneration in elderly subjects. The system can be applied with good intra- and interobserver agreement.

Imaging of salivary gland tumours

Salivary gland neoplasms account for <3% of all tumors. Most of them are benign and parotid gland is the commonest site. As a general rule, the smaller the involved salivary gland, the higher is the possibility of the tumor being malignant. The role of imaging in assessment of salivary gland tumour is to define intra-glandular vs. extra-glandular location, detect malignant features, assess local extension and invasion, detect nodal metastases and systemic involvement. Image guided fine needle aspiration cytology provides a safe means to obtain cytological confirmation. For lesions in the superficial parotid and submandibular gland, ultrasound is an ideal tool for initial assessment. These are superficial structures accessible by high resolution ultrasound and FNAC which provides excellent resolution and tissue characterization without a radiation hazard. Nodal involvement can also be assessed. If deep tissue extension is suspected or malignancy confirmed on cytology, an MRI or CT is mandatory to evaluate tumour extent, local invasion and perineural spread. For all tumours in the sublingual gland, MRI should be performed as the risk of malignancy is high. For lesions of the deep lobe of parotid gland and the minor salivary glands, MRI and CT are the modalities of choice. Ultrasound has limited visualization of the deep lobe of parotid gland which is obscured by the mandible. Minor salivary gland lesions in the mucosa of oral cavity, pharynx and tracheo-bronchial tree, are also not accessible by conventional ultrasound. Recent study suggests that MR spectroscopy may differentiate malignant and benign salivary gland tumours as well as distinguishing Warthins tumor from pleomorphic adenoma. However, its role in clinical practice is not well established. Similarly, the role of nuclear medicine and PET scan, in imaging of parotid masses is limited. Sialography is used to delineate the salivary ductal system and has limited role in assessment of tumour extent.

Prospective comparison of three predictive rules for assessing severity of community-acquired pneumonia in Hong Kong

Background: Community-acquired pneumonia (CAP) is a leading infectious cause of death throughout the world, including Hong Kong. Aim: To compare the ability of three validated prediction rules for CAP to predict mortality in Hong Kong: the 20 variable Pneumonia Severity Index (PSI), the 6-point CURB65 scale adopted by the British Thoracic Society and the simpler CRB65. Methods: A prospective observational study of 1016 consecutive inpatients with CAP (583 men, mean (SD) age 72 (17) years) was performed in a university hospital in the New Territories of Hong Kong in 2004. The patients were classified into three risk groups (low, intermediate and high) according to each rule. The ability of the three rules to predict 30 day mortality was compared. Results: The overall mortality and intensive care unit (ICU) admission rates were 8.6% and 4.0%, respectively. PSI, CURB65 and CRB65 performed similarly, and the areas under the receiver operating characteristic (ROC) curve were 0.736 (95% CI 0.687 to 0.736), 0.733 (95% CI 0.679 to 0.787) and 0.694 (95% CI 0.634 to 0.753), respectively. All three rules had high negative predictive values but relatively low positive predictive values at all cut-off points. Larger proportions of patients were identified as low risk by PSI (47.2%) and CURB65 (43.3%) than by CRB65 (12.6%). Conclusion: All three predictive rules have a similar performance in predicting the severity of CAP, but CURB65 is more suitable than the other two for use in the emergency department because of its simplicity of application and ability to identify low-risk patients.

Shear wave elastography of focal salivary gland lesions: preliminary experience in a routine head and neck US clinic

Book synopsis: New Materialisms rethinks the relevance of materialist philosophy in the midst of a world shaped by forces such as digital and biotechnologies, global warming, global capital, and population flows. Moving away from modes of inquiry that have prioritized the study of consciousness and subjectivity over matter, the essays in this collection show that any account of experience, agency, and political action demands renewed attention to the urgent issues of our own material existence and our environment. The editors propose “new materialisms” as a way to take matter seriously without falling into the conceptual dualism that posits an opposition between matter and thought, materialism and idealism, and body and mind. They locate new materialisms within post-humanist discourses, explaining that new materialist philosophies do not privilege human bodies, but rather view human bodies as one of many bodies, or agential materialities, in the world. By revealing how emerging accounts of matter, materiality, and corporeality are combining with developments in science and technology to demand radically new conceptions of nature, agency, and social and political relationships, New Materialisms makes a significant contribution to the recent resurgence of interest in phenomenology and materialist philosophy in the humanities.

Neck node metastases from nasopharyngeal carcinoma: MR imaging of patterns of disease.

The purpose was to use MR imaging to document the patterns of nodal involvement in the upper neck in nasopharyngeal carcinoma (NPC).

Ultrasound of malignant cervical lymph nodes

Abstract Malignant lymph nodes in the neck include metastases and lymphoma. Cervical nodal metastases are common in patients with head and neck cancers, and their assessment is important as it affects treatment planning and prognosis. Neck nodes are also a common site of lymphomatous involvement and an accurate diagnosis is essential as its treatment differs from other causes of neck lymphadenopathy. On ultrasound, grey scale sonography helps to evaluate nodal morphology, whilst power Doppler sonography is used to assess the vascular pattern. Grey scale sonographic features that help to identify metastatic and lymphomatous lymph nodes include size, shape and internal architecture (loss of hilar architecture, presence of intranodal necrosis and calcification). Soft tissue oedema and nodal matting are additional grey scale features seen in tuberculous nodes or in nodes that have been previously irradiated. Power Doppler sonography evaluates the vascular pattern of nodes and helps to identify the malignant nodes. In addition, serial monitoring of nodal size and vascularity are useful features in the assessment of treatment response.

Evaluation of WHO criteria for identifying patients with severe acute respiratory syndrome out of hospital: prospective observational study

Abstract Objectives To determine the clinical and radiological features of severe acute respiratory syndrome (SARS) and to evaluate the accuracy of the World Health Organizations guidelines on defining cases of SARS. Design Prospective observational study. Setting A newly set up SARS screening clinic in the emergency department of a university hospital in Hong Kongs New Territories. Participants 556 hospital staff, patients, and relatives who attended the screening clinic and who had had contact with someone with SARS. Main outcome measure Number of confirmed cases of SARS. Results Of the 556 people, 141 were admitted to hospital, and 97 had confirmed SARS. Fever, chills, malaise, myalgia, rigor, loss of appetite, vomiting, diarrhoea, and neck pain but not respiratory tract symptoms were significantly more common among the 97 patients than among the other patients. The overall accuracy of the WHO guidelines for identifying suspected SARS was 83% and their negative predictive value was 86% (95% confidence interval 83% to 89%). They had a sensitivity of 26% (17% to 36%) and a specificity of 96% (93% to 97%). Conclusions Current WHO guidelines for diagnosing suspected SARS may not be sufficiently sensitive in assessing patients before admission to hospital. Daily follow up, evaluation of non-respiratory, systemic symptoms, and chest radiography would be better screening tools.