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Anil T Ahuja

Publications and source records attributed to Anil T Ahuja.

36 records · Page 2Linked to original sources
PubMed2004

Comparison of CT and MR imaging for the detection of extranodal neoplastic spread in metastatic neck nodes.

PURPOSE: To compare computed tomography (CT) and magnetic resonance (MR) imaging for the detection of extranodal neoplastic spread (ENS) in metastatic cervical nodes from head and neck squamous cell carcinoma. MATERIALS AND METHODS: 17 patients with a squamous cell carcinoma of the head and neck underwent CT and MR imaging. The neck nodes were assessed for ENS and the results compared using pathology from the surgical resection. RESULTS: Radiologic-pathologic correlation was performed in 51 malignant nodes. The accuracy, sensitivity and specificity were respectively 73, 65, 93% for CT, and 80, 78, 86% for MR imaging. Comparison of CT and MR imaging showed that there was no significant difference between the two modalities for either sensitivity (P = 0.1317) or specificity (P = 0.3173). CONCLUSION: CT and MR imaging are comparable for the detection of ENS.

Aged↗
PubMed2004

Grey-scale and power Doppler sonography of unusual cervical lymphadenopathy.

This study was undertaken to document the grey-scale and power Doppler sonographic features of cervical lymphadenopathy in Kikuchi's disease (histiocytic necrotising lymphadenitis), Rosai-Dorfman disease (sinus histiocytosis with massive lymphadenopathy), Sjogren's syndrome and systemic lupus erythematosus (SLE), which have not been reported in the literature. A retrospective review of the grey-scale and power Doppler sonograms of the cervical lymph nodes in nine patients was conducted (Kikuchi's disease, n = 3; Rosai-Dorfman disease, n = 1; Sjogren's syndrome, n = 1; SLE, n = 4). Lymph nodes were proven to be pathologic by fine-needle aspiration cytology (FNAC). On grey-scale ultrasound (US), lymph nodes were assessed by their distribution, size, shape, echogenicity and internal architecture. The vascular pattern of the lymph nodes was assessed with power Doppler sonography. US features of the lymph nodes were compared to those of metastatic and reactive nodes. In Kikuchi's disease, Rosai-Dorfman disease, Sjogren's syndrome and SLE, the distribution of lymph nodes is similar to that of reactive nodes. Most of the lymph nodes are enlarged with a maximum transverse diameter greater than or equal to 10 mm (83.3 to 100%). In Kikuchi's disease, lymph nodes have grey-scale and Doppler appearances similar to reactive nodes. However, lymph nodes in Rosai-Dorfman disease, Sjogren's syndrome and SLE show similar grey-scale and Doppler features to metastatic nodes. There is no specific US feature to characterise lymphadenopathy from these four miscellaneous causes. Definitive diagnosis should still be based on cytology and histology, and US can help in guiding FNAC for a more accurate cytologic examination.

Adolescent↗
PubMed2004

Evaluation of cervical lymph node vascularity: a comparison of colour Doppler, power Doppler and 3-D power Doppler sonography.

This study was undertaken to compare the performance of colour Doppler (CDS), power Doppler (PDS) and 3-D power Doppler sonography (3-D PDS) in the assessment of vascular pattern and vessel displacement of cervical lymph nodes. Colour Doppler (2-D CDS), power Doppler (2-D PDS) and 3-D power Doppler sonograms (3D PDS) of 145 cervical nodes were reviewed (metastases n=60, lymphoma n=30, tuberculosis n=23, reactive n=25, Kimura disease n=7). Sonograms of the three imaging modes were reviewed separately with an interval of 2 weeks. Lymph nodes were assessed for the vascular pattern (hilar, peripheral or mixed) and the presence or absence of displacement of hilar vascularity. For the assessment of displacement of hilar vascularity, only lymph nodes that showed hilar or mixed vascularity in the three imaging modes were included in the analysis. Results showed that there was a high level of agreement between CDS and PDS in assessment of vascular patterns (kappa=0.914), whereas the level of agreement between CDS and 3-D PDS (kappa=0.484) and between PDS and 3-D PDS (kappa=0.452) was low. There was a high level of agreement in the assessment of displacement of hilar vascularity among the three imaging modes (CDS and PDS, kappa=0.942; CDS and 3-D PDS, kappa=0.808; PDS and 3-D PDS, kappa=0.865). In the assessment of vascular patterns of cervical lymphadenopathy, CDS and PDS have a similar performance. However, accurate assessment of the vascular pattern of cervical nodes may be difficult using 3-D PDS. In the assessment of displacement of hilar vascularity, the performances of CDS, PDS and 3-D PDS are similar.

Adolescent↗
PubMed2004

Necrosis in metastatic neck nodes: diagnostic accuracy of CT, MR imaging, and US.

PURPOSE: To compare the diagnostic accuracy of computed tomography (CT), magnetic resonance (MR) imaging, and ultrasonography (US) in the detection of necrosis in metastatic cervical nodes from patients with head and neck squamous cell carcinoma. MATERIALS AND METHODS: Twenty-seven patients (age range, 39-85 years; mean age, 62 years) with squamous cell carcinoma in the head and neck underwent CT, MR imaging, and US. Three radiologists evaluated the images for nodal necrosis. The results of each modality were analyzed for sensitivity, specificity, and accuracy. Pathologic analysis of the surgical resection served as the reference standard. The three modalities were compared for specificity and sensitivity with the McNemar test. RESULTS: Pathologic examination revealed 903 nodes, of which 89 were malignant. Of the malignant nodes, 43 were necrotic. Analysis of the detection of necrosis in the 89 malignant nodes showed an accuracy, sensitivity, and specificity of 92%, 91%, and 93% for CT; 91%, 93%, and 89% for MR imaging; and 85%, 77%, and 93% for US, respectively. All imaging modalities failed to depict necrotic areas of 3 mm or smaller in three nodes, and necrosis was missed in an additional seven nodes with US and in one node with CT. Necrosis could not be distinguished from other components of malignancy, such as viable tumor and scar tissue, in seven nodes (CT, 3; MR imaging, 5; US, 3). The sensitivity of both MR imaging and CT was significantly better than that of US (P =.0082 and P =.0339, respectively). There was no significant difference in sensitivity (P =.3173) between MR imaging and CT, or in the specificity of the three modalities. CONCLUSION: MR imaging is comparable to CT for the detection of necrosis. The sensitivity of MR imaging and CT is better than that of US.

Adult↗
PubMed2004

Late-stage adult respiratory distress syndrome caused by severe acute respiratory syndrome: abnormal findings at thin-section CT.

PURPOSE: To evaluate thin-section computed tomographic (CT) abnormalities in patients in the intensive care unit during the late stage of adult respiratory distress syndrome (ARDS) caused by severe acute respiratory syndrome (SARS). MATERIALS AND METHODS: Eight patients in the late stage of ARDS (ie, more than 2 weeks after onset) were imaged with thin-section CT. Images were evaluated for ground-glass opacification, consolidation, interstitial thickening, evidence of fibrosis, and any other abnormalities. Patient records were reviewed, and relevant respiratory and ventilatory parameters, total steroid dose, and outcome were recorded. RESULTS: All patients received high-dose pulse methylprednisolone (minimum, 2.5 g total), and all patients who received ventilation received low-pressure, low-volume ventilation. Five patients received prolonged mechanical ventilation (for more than 14 days), one received ventilation for 72 hours, and two patients did not receive ventilation. Three patients died, four were discharged from the hospital, and one continued to require ventilation. Ground-glass opacification and interstitial thickening were present at CT in all eight patients. Consolidation was present in six patients. Three patients had evidence of fibrosis. Patients who received long-term ventilation, those who received short-term ventilation, and those who did not receive ventilation had similar pulmonary changes at CT. Pulmonary cysts, most of which were small (<1 cm), were present in five patients. Cysts were present in one patient who received only short-term low-pressure and low-volume ventilation and in one patient who received no mechanical ventilation. CONCLUSION: The CT features of late-stage ARDS caused by SARS are similar to those seen in late-stage ARDS of other causes, with no apparent differences between patients who do and patients who do not receive prolonged mechanical ventilation. The presence of cysts in one patient who received short-term and one patient who received no mechanical ventilation suggests that severe SARS-induced ARDS may independently result in cyst formation.

Adult↗
PubMed2004

Non-Hodgkin lymphoma of the larynx: CT and MR imaging findings.

BACKGROUND AND PURPOSE: Non-Hodgkin lymphoma (NHL) of the larynx is a rare tumor. The aim of this study was to report the CT and MR features of laryngeal NHL in four patients to determine if there are any features that might be helpful to distinguish NHL from other laryngeal tumors. METHODS: The CT and MR images of four patients with laryngeal NHL were retrospectively reviewed for tumor volume and distribution, appearance, local invasion, and lymphadenopathy. RESULTS: Tumor volume ranged from 4 to 45 mL(3). Tumor was based in the submucosal (2/4 [50%]), mucosal (1/4 [25%]), or both regions (1/4 [25%]) and was centered in the supraglottis (4/4 [100%]) but also involved the glottis (4/4 [100%]) and subglottis (2/4 [50%]). Laryngeal tumor involved the aryepiglottic folds (4/4 [100%)]), ventricles and false cords (4/4 [100%]), epiglottis (3/4 [75%]), paraglottis (3/4 [75%]), true cords (4/4 [100%]), anterior commissure (4/4 [100%]), and laryngeal cartilage (1/4 [25%]). The tumor extended into the hypopharynx (4/4 [100%]), strap muscles (1/4 [25%]), prevertebral muscles (1/4 [25%]), tongue base (1/4 [25%]), and walls of the oropharynx (1/4 [25%]) and nasopharynx (1/4 [25%]). Bilateral cervical lymphadenopathy with extracapsular tumor spread was present in one patient. CONCLUSION: Laryngeal NHL is a tumor that usually has a large submucosal component centered in the surpaglottis. The tumor extends into the glottis, with less frequent spread to the subglottis, laryngeal cartilage, and strap muscles. Laryngeal NHL also involves the hypopharynx, with large tumors extending superiorly into the tongue base, oropharynx, and nasopharynx. A laryngeal tumor with a large supraglottic submucosal component should alert the ragiologist to the possibility of NHL.

Adult↗
PubMed2004

External jugular vein vascular malformation: sonographic and MR imaging appearances.

Vascular malformations arising from the wall of the external jugular vein are rare. This case series discusses the sonographic and MR imaging appearances of four such cases and reviews the literature. The diagnosis should be suggested preoperatively particularly because of the close relationship such malformations to the external jugular vein, as this helps surgeons to plan the operative procedure. The imaging appearances are similar to those of other vascular malformations elsewhere in the head and neck.

Adult↗
PubMed2004

In vivo proton MR spectroscopy of primary and nodal nasopharyngeal carcinoma.

BACKGROUND AND PURPOSE: The aim of this study was to determine the feasibility of performing in vivo proton ((1)H) MR spectroscopy of nasopharyngeal carcinoma (NPC) and to document the (1)H spectrum of this cancer. METHODS: Twenty-seven patients with NPC lesions >1 cm(3) underwent localized (1)H MR spectroscopy performed at 1.5 T. Water-suppressed spectra from both primary tumors (nine cases) and metastatic nodes (18 cases) were obtained at TE 136 and 272. Spectra were analyzed in the time domain by using a nonlinear least squares fitting algorithm with incorporation of previous knowledge. Choline (Cho)/creatine (Cr) ratios for primary NPC and metastatic nodes were calculated and compared. Spectra from normal neck muscle of five volunteers were acquired as control data. RESULTS: (1)H MR spectroscopy was successfully obtained in seven (78%) of nine primary tumors and 16 (89%) of 18 metastatic nodes. Intense lipid signals in the range of 0.89 to 2.02 ppm were observed in 95% of spectra at TE 136 and 91% of spectra at TE 272. At TE 136, Cho/Cr for metastatic nodes (5.3 +/- 1.6) was significantly higher than the ratio for primary (2.6 +/- 0.5) NPC lesions (P =.02). Cho/Cr ratios for NPC lesions were higher than those for normal neck muscles, for which values ranged from 0 to 0.97 and 0 to 1.1 at TE 136 and 272, respectively. CONCLUSION: (1)H MR spectroscopy is a feasible technique for the evaluation of NPC tumors >1 cm(3). Cho/Cr ratios for the lesions were high compared with those for normal neck muscle.

Adult↗
PubMed2003

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

OBJECTIVES: To determine the clinical and radiological features of severe acute respiratory syndrome (SARS) and to evaluate the accuracy of the World Health Organization's 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 Kong's 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.

Adult↗
PubMed2003

Thin-section CT in patients with severe acute respiratory syndrome following hospital discharge: preliminary experience.

PURPOSE: To report the initial experience regarding thin-section computed tomographic (CT) findings in patients with severe acute respiratory syndrome (SARS) who improved clinically after treatment. MATERIALS AND METHODS: Twenty-four patients (10 men, 14 women; mean age, 39 years; age range, 23-70 years) with confirmed SARS underwent follow-up thin-section CT of the thorax. The scans were obtained on average 36.5 days after hospital admission and were analyzed for parenchymal abnormality (ground-glass opacification, consolidation, or interstitial thickening) and evidence of fibrosis (parenchymal band, traction bronchiectasis, irregular interfaces). Patients were assigned to group 1 (with CT evidence of fibrosis) and group 2 (without CT evidence of fibrosis) for analysis. Patient demographics, length of hospital stay, rate of intensive care unit admission, peak lactate dehydrogenase level, pulsed intravenous methylprednisolone therapy, and peak opacification on chest radiographs were compared between the two groups. RESULTS: Parenchymal abnormality was found in 96% (23 of 24) of patients and ranged from residual ground-glass opacification and interstitial thickening in group 2 (nine of 24, 38%) to fibrosis in group 1 (15 of 24, 62%). Patients in group 1 were older (mean age, 45 vs 30.3 years), had a higher rate of intensive care unit admission (27% [four of 15] vs 11% [one of nine]), more requirement for pulsed intravenous methylprednisolone (87%, [13 of 15] vs 67% [six of nine]), higher peak lactate dehydrogenase level (438.9 vs 355.6 U/L), and higher peak opacification on chest radiographs (estimated area, 14% vs 11%) than patients in group 2. CONCLUSION: Pulmonary fibrosis may develop early in patients with SARS who have been discharged after treatment. Patients who are older and have more severe disease during treatment are more likely to develop thin-section CT findings of fibrosis.

Adult↗
PubMed2003

Severe acute respiratory syndrome: radiographic appearances and pattern of progression in 138 patients.

PURPOSE: To retrospectively evaluate the radiographic appearances and pattern of progression of severe acute respiratory syndrome (SARS). MATERIALS AND METHODS: Chest radiographs obtained at clinical presentation and during treatment in 138 patients with confirmed SARS (66 men, 72 women; mean age, 39 years; age range, 20-83 years) were assessed. Radiographic appearances of pulmonary parenchymal abnormality, distribution, and extent of involvement on initial chest radiographs were documented. Recognizable patterns of radiographic progression were determined by comparing the overall mean percentage of lung involvement for each patient on serial radiographs. RESULTS: Initial chest radiographs were abnormal in 108 of 138 (78.3%) patients and showed air-space opacity. Lower lung zone (70 of 108, 64.8%) and right lung (82 of 108, 75.9%) were more commonly involved. In most patients, peripheral lung involvement was more common (81 of 108, 75.0%). Unifocal involvement (59 of 108, 54.6%) was more common than multifocal or bilateral involvement. No cavitation, lymphadenopathy, or pleural effusion was demonstrated. Four patterns of radiographic progression were recognized: type 1 (initial radiographic deterioration to peak level followed by radiographic improvement) in 97 of 138 patients (70.3%), type 2 (fluctuating radiographic changes) in 24 patients (17.4%), type 3 (static radiographic appearance) in 10 patients (7.3%), and type 4 (progressive radiographic deterioration) in seven patients (5.1%). Initial focal air-space opacity in 44 of 59 patients (74.6%) progressed to unilateral multifocal or bilateral involvement during treatment. CONCLUSION: Predominant peripheral location; common progression pattern from unilateral focal air-space opacity to unilateral multifocal or bilateral involvement during treatment; and lack of cavitation, lymphadenopathy, and pleural effusion are the more distinctive radiographic findings of SARS.

Adult↗
PubMed2003

Thin-section CT of severe acute respiratory syndrome: evaluation of 73 patients exposed to or with the disease.

PURPOSE: To retrospectively analyze the thin-section computed tomographic (CT) features in patients with severe acute respiratory syndrome (SARS) at the authors' institution. MATERIALS AND METHODS: From March 11, 2003, to April 2, 2003, 74 patients with symptoms and signs suggestive of SARS underwent CT of the thorax; all underwent thin-section CT except for one patient who underwent conventional CT. Group 1 (n = 23) patients had symptoms of SARS in keeping with criteria from the Centers for Disease Control and Prevention and a positive chest radiograph. Group 2 (n = 17) patients had a high clinical suspicion of SARS but a normal radiograph. Group 3 (n = 34) patients had minor symptoms and a normal chest radiograph. The thin-section CT images were analyzed for ground-glass opacification or consolidation, lesion size in each lung segment, peripheral or central location, interstitial thickening, and other abnormalities. RESULTS: Thin-section CT scans were abnormal only for patients in groups 1 and 2. The patient with only conventional CT scans was in group 3; scans for group 3 patients were normal. Affected segments were predominantly in the lower lobes (91 of 149 affected segments). Common findings included ground-glass opacification, sometimes with consolidation, and interlobular septal and intralobular interstitial thickening. The size of each lesion and the total number of segments involved were smaller in group 2 patients. A majority of patients in group 1 (14 of 23) had mixed central and peripheral lesions. In group 2, however, peripheral lesions were more common (10 of 17). In both groups, a purely central lesion was uncommon (one of 23 in group 1 and two of 17 in group 2). CONCLUSION: Common thin-section CT features of SARS are ground-glass opacification and lower lobe and peripheral distribution.

Adolescent↗
PubMed2003

Tuberculosis of the nasopharynx: a rare entity revisited.

OBJECTIVES: Tuberculosis of the nasopharynx is uncommon. A large series of 17 cases is reported, and the clinical and pathological features are discussed. STUDY DESIGN: A retrospective review. METHODS: Seventeen archived cases of biopsy-proven nasopharyngeal tuberculosis were reviewed for patient age and sex, presenting complaint and duration, systemic symptoms, cervical lymphadenopathy, and chest x-ray findings. These findings were compared with a compilation of 40 cases reported in the English literature. RESULTS: There was a female predominance (13 women and 4 men), with age range of 20 to 74 years (mean age, 38 y). The most common presentation was enlargement of the cervical lymph nodes (53%), followed by hearing loss (12%), tinnitus, otalgia, nasal obstruction, and postnasal drip (6% each). The duration of the presenting symptoms ranged from 1 week to 1 year (mean duration, 16 wk). Ten patients (59%) had cervical lymphadenopathy, two (12%) had systemic symptoms (fever, weight loss, night sweats), and one patient (6%) had miliary pulmonary tuberculosis. Direct endoscopic examination showed nasopharyngeal mucosal irregularity or mass in the majority of patients (12 patients [70%]). These features were similar to those reported in the literature. CONCLUSIONS: Nasopharyngeal tuberculosis is uncommon, usually occurring without pulmonary or systemic involvement. Cervical lymphadenopathy occurs in more than half of the patients and is the most common presenting complaint; this, together with the nasopharyngeal findings of mass or mucosal irregularity, makes differentiation from carcinoma on clinical examination difficult, necessitating histological evaluation.

Adult↗
PubMed2003

MR imaging features of nasopharyngeal tuberculosis: report of three cases and literature review.

The MR imaging appearances in three cases of nasopharyngeal tuberculosis are reported, and the findings are combined with three additional cases from a review of the literature. Two patterns of nasopharyngeal tuberculosis were identified. The first pattern is a discrete polypoid mass in the adenoids, and the second pattern is a more diffuse soft-tissue thickening of one or two of the walls of the nasopharynx. Extension outside the confines of the nasopharynx was not a feature, except in one case with early involvement of the prevertebral muscles.

Adult↗
PubMedDate not supplied

Thyrotoxic periodic paralysis: sonographic appearances of the thyroid.

PURPOSE: The aim of the study was to describe the sonographic appearances of the thyroid in patients with thyrotoxic periodic paralysis (TPP). METHODS: Of the 25 patients diagnosed with TPP between January 1, 1998, and December 31, 2001, as identified by a search of our patient database, 13 had undergone sonography of the thyroid. We retrospectively reviewed the clinical records and thyroid sonograms of these 13 patients. The sonograms were assessed subjectively for thyroid size, echogenicity, vascularity, and the presence of solid nodules and cysts. RESULTS: Sonography showed abnormality of the thyroid in all 13 patients. In 11 patients (85%), sonography showed widespread hypoechogenicity (compared with the muscle) whose distribution was diffuse (6 patients) or patchy (5 patients) and diffusely distributed areas of hypervascularity (type 1 pattern). All 11 of these patients had a clinical diagnosis of Graves' disease. One patient (8%) had multinodular goiter and enlargement of the thyroid with multiple heterogeneous solid nodules and cysts (type 2 pattern); the clinical diagnosis was toxic multinodal goiter. One patient (8%) had a combination of type 1 and type 2 patterns and a clinical diagnosis of Graves' disease. CONCLUSIONS: The sonographic abnormalities of the thyroid in patients with TPP reflect the common underlying causes of thyrotoxicosis in the general population. The sonographic appearances associated with Graves' disease (type 1 pattern) were the most common abnormality detected. No sonographic features specific to TPP were identified.

Adult↗
PubMedDate not supplied

Severe acute respiratory syndrome: thin-section computed tomography features, temporal changes, and clinicoradiologic correlation during the convalescent period.

OBJECTIVE: To evaluate thin-section computed tomography findings of patients with severe acute respiratory syndrome (SARS) in the convalescent period and to correlate the results with clinical parameters and lung function tests. METHODS: Ninety-nine severe acute respiratory syndrome patients with persistent changes on follow-up chest radiography were included. One hundred seventy computed tomography examinations at baseline (n=70), 3 months (n=56), and 6 months (n=44) were retrospectively evaluated to determine the extent of ground-glass opacification, reticulation, and total parenchymal involvement. Patients' demographic information, clinical information during treatment, and results of lung function tests at 3 and 6 months were correlated with computed tomography findings. RESULTS: A significant serial improvement in the extent of overall ground-glass opacification, overall reticulation, and total parenchymal involvement was observed (P <0.01). Advanced age, previous intensive care unit admission, mechanical ventilation, alternative treatment, higher peak lactate dehydrogenase, and peak radiographic involvement during treatment showed a positive correlation with overall reticulation and total parenchymal involvement at 6 months. There was a significant negative correlation between overall reticulation and total parenchymal involvement with diffusion capacity adjusted for hemoglobin at 3 and 6 months (P <0.01). CONCLUSION: Lung changes on thin-section computed tomography of severe acute respiratory syndrome patients improved with time during the convalescent period and showed a significant correlation with advanced age, parameters indicating severe illness, and diffusion capacity adjusted for hemoglobin on follow-up.

Adult↗