PubMed Health⌕ Search

Biomedical subjects

A T Ahuja

Publications and source records attributed to A T Ahuja.

At least 37 records · Page 2Linked to original sources
PubMed2003

Non-Hodgkin's lymphoma of the nasopharynx: CT and MR imaging.

OBJECTIVE: Nasopharyngeal (NP) non-Hodgkin's lymphoma (NHL) is an uncommon tumour. The aim of the study was to describe the appearances on CT and MR imaging, and identify the features which help to distinguish NPNHL from other NP tumours. MATERIALS AND METHODS: The CT (n=8) and MR (n=10) images of 14 patients with NPNHL were reviewed retrospectively. Patients with NPNHL were divided into primary NPNHL, where the primary tumour was in the NP (n=7) and secondary NPNHL where the primary tumour was at another extranodal site in the head and neck (n=7). All NPNHL were assessed for tumour size and distribution, appearance and local tumour invasion, in addition lymphadenopathy was assessed in primary NPNHL. RESULTS: The NPNHL ranged in size from 20-75 mm (mean of 55 mm for primary and 30 mm for secondary NHL) and were homogeneous on CT in eight (100%) and MR in seven (70%) and mildly heterogeneous on MR in three (30%) patients. NPNHL involved all walls of the NP in 10 (71%) (n=1). Primary NPNHL extended superficially in five (71%) to involve the nasal cavity (n=3) and oropharynx (n=2) and lymphadenopathy was present in five (71%) being bilateral and involving multiple nodal sites (n=4) with necrosis (n=2) and matting (n=3). CONCLUSION: NPNHL is a homogeneous tumour that tends to diffusely involve all walls of the nasopharynx and spread in an exophytic fashion to fill the airway, rather than infiltrating into the deep tissues. Deep tumour infiltration, when it occurs, is found in those patients with primary NHL and is usually limited in extent and of small volume. and extended in an exophytic fashion to fill the NP cavity in six (43%). Deep tumour invasion was present in two (14%) both patients with primary NHL, the extent and volume of this tumour invasion was small and involved the prevertebral muscles (n=2), parapharyngeal fat space (n=1) and skull base Primary NHL more commonly spreads superficially to involve the nasal cavity or oropharynx, lymphadenopathy is frequent and extensive. A large tumour that fills the nasopharynx, with no or minimal invasion into deep structures, and a propensity to extend down into the tonsil, rather than up into the skull base, may suggest the diagnosis of NHL over nasopharyngeal carcinoma.

Adult↗
PubMed2003

Computed tomography of common congenital lesions of the temporal bone.

This pictorial review describes the application of high-resolution computed tomography to the investigation and pre-operative work-up of the common lesions of congenital hearing loss, including congenital aural dysplasia, various congenital ossicular anomalies, inner ear dysmorphology, large vestibular aqueduct syndrome, and congenital absence of cochlear nerve and labyrinthitis ossificans from previous infection. The aim is to help radiologists to provide a more accurate diagnosis of underlying aetiology and assist in surgical planning.

Cochlea↗
PubMed2003

Computed tomography imaging of the temporal bone--normal anatomy.

This review describes the fundamental anatomical structures of the temporal bone as depicted on high-resolution computed tomography, and the clinical significance of these structures. It is not an encyclopaedic atlas, but provides the junior radiology/otorhinolaryngology resident with sufficient knowledge for interpretation of most of the imaging studies encountered in daily clinical practice.

Ear Canal↗
PubMed2003

Accuracy of high-resolution sonography compared with magnetic resonance imaging in the diagnosis of head and neck venous vascular malformations.

AIMS: To evaluate whether modern ultrasound examination helps to establish the diagnosis of head and neck venous vascular malformations (VVMs) and whether it can delineate their full extent. MATERIALS AND METHODS: Sonographic appearances of 30 head and neck VVMs were assessed for: location, extent, internal architecture, presence of flow and phleboliths. These results were compared with the magnetic resonance imaging (MRI) of the same patients. RESULTS: The lesions showed well-defined margins (22 of 30, 73%), heterogeneous (30 of 30, 100%) and hypoechoic echo pattern (27 of 30, 90%), with sinusoidal spaces (28 of 30, 93%) and phleboliths (24 of 30, 80%) on grey-scale imaging, and flow signal on Doppler (28 of 30, 93%). For delineating the extent, ultrasound was comparable with MRI in 53% (16 of 30) and inferior to MRI in 47% (14 of 30). Ultrasound did not detect deeper extent, intra-osseous involvement and other clinically occult VVMs. CONCLUSION: Ultrasound with high-resolution transducers can confidently suggest the diagnosis of head and neck VVMs in up to 90% of cases, and delineate the full extent of some superficial lesions. The major disadvantage is its inability to evaluate intra-osseous involvement and the entire extent of large, deep-seated lesions.

Adolescent↗
PubMed2003

Imaging in severe acute respiratory syndrome (SARS).

Severe acute respiratory syndrome (SARS) is a highly infectious disease caused by a novel coronavirus, and has become pandemic within a short period of time. Imaging plays an important role in the diagnosis, management and follow-up of patients with SARS. The current status of imaging in SARS is presented in this review.

Adolescent↗
PubMed2003

Kuttner tumour (chronic sclerosing sialadenitis) of the submandibular gland: sonographic appearances.

Patients with Kuttner tumours present with clinical features simulating a submandibular tumour. This article aims to familiarise sonologists with the sonographic appearances of these tumours, to help in their differentiation from other salivary lesions. In 13 patients with histologically or cytologically proven Kuttner tumours, the features evaluated on sonography included: shape and border of the gland, internal architecture, duct dilatation, presence/absence of calculi and presence and distribution of vascularity. There was diffuse involvement of the submandibular glands in 11 patients and focal involvement in 2. The majority (9 of 11) of the patients with diffuse involvement showed sonographic appearances simulating a "cirrhotic" liver; 2 showed diffuse heterogeneous involvement with duct dilatation and calculus. Doppler showed prominent intraglandular vessels, with no evidence of displacement. Focal lesions (2 of 11) were seen as hypoechoic, heterogeneous "masses," with a radial branching vascular pattern within, on Doppler. In conclusion, sonographic features may help in identifying Kuttner tumours of the submandibular glands.

Adult↗
PubMed2003

Is neck ultrasound necessary for early stage oral tongue carcinoma with clinically N0 neck?

OBJECTIVES: To define the necessity of neck ultrasound for investigation of T1 and T2 oral tongue carcinoma with N0 neck. METHODS: The medical records of all patients with early stage (T1-2 N0) oral tongue cancer treated surgically between January 1985 and December 2000 were reviewed. Patients with 30 neck dissections were identified for analysis. The result of neck ultrasound examination was correlated with the histological examination. RESULTS: The sensitivity, specificity and overall accuracy of ultrasound examination were found to be 47%, 93% and 70%, respectively. The implication of ultrasound examination with respect to elective neck treatment was discussed in the management of the N0 neck. CONCLUSIONS: It is concluded that ultrasound alone is inadequate for making decisions regarding neck management of patients with T1 and T2 N0 carcinoma of the tongue and cannot replace a policy of elective neck dissection.

Carcinoma↗
PubMed2001

Extranodal manifestation of Kimura's disease: ultrasound features.

We describe the imaging features of a 53-year-old Chinese patient with Kimura's disease (KD) who presented with a dominant right-cheek subcutaneous mass. The lesion appeared as an ill-defined mass within the subcutaneous tissues with a "wooly" echotexture on US. The differential diagnosis and a review of the literature are discussed.

Angiolymphoid Hyperplasia with Eosinophilia↗
PubMed2001

Distribution of intranodal vessels in differentiating benign from metastatic neck nodes.

AIM: Recent studies report high accuracy of power Doppler sonography in the differentiation of benign from malignant cervical lymphadenopathy. This study was undertaken to identify which of the parameters used in Doppler sonography of cervical lymph nodes is accurate and readily applicable in routine clinical practice. MATERIALS AND METHODS: We reviewed the power Doppler ultrasound examinations of 50 patients with cytologically proven metastatic nodes from nasopharyngeal carcinoma and 50 patients with proven reactive lymphadenopathy. All the examinations had been performed by an experienced sonologist, and intranodal vascular distribution and resistance were evaluated during real-time ultrasound. Twenty metastatic nodes and 40 reactive nodes were less than 10 mm in maximum transverse diameter. The vascular patterns of lymph nodes were classified into three categories: (1) hilar; (2) capsular; (3) hilar and capsular. The resistive index (RI) and pulsatility index (PI) were measured by spectral Doppler. RESULTS: Although metastatic nodes (RI, 0.81 +/- 0.11; PI, 1.89 +/- 0.89) tended to have higher intranodal vascular resistance than reactive nodes (RI, 0.65 +/- 0.08; PI, 1.07 +/- 0.26), there was considerable overlap of the resistance parameters between benign and malignant nodes. Most of the metastatic nodes showed the presence of capsular vascularity (capsular, 16%; capsular and hilar, 78%), whereas the majority of the reactive nodes showed hilar vascularity (98%), and the difference was significant. CONCLUSION: The distribution of intranodal vascularity appears to be more useful than RI or PI in differentiating benign from malignant cervical lymphadenopathy. It is also easier to evaluate the distribution and the results are therefore readily applicable in routine clinical practice.

Adult↗
PubMed2001

Does anybody know how we should measure Doppler parameters in lymph nodes?

AIM: To show how currently described techniques confuse interpretation of Doppler indices in lymph node characterization. MATERIALS AND METHODS: The Doppler indices [resistivity index (RI) and pulsatility index (PI)] were obtained in 35 malignant lymph nodes by colour duplex sonography. Each node was sampled at eight different sites. Data were analysed using our own method, and methods employed in six previous studies. RESULTS: Restistivity index values varied between 0.69 and 0.88 and PI values ranged from 1.28 to 2.34. All but two methods produced different resistance indices (P < 0.05). CONCLUSION: Conflicting results are obtained analysing the same data using different methods. Standardized techniques should be agreed and employed in future studies.

Blood Flow Velocity↗
PubMed2001

Power Doppler sonography of metastatic nodes from papillary carcinoma of the thyroid.

AIMS: Metastatic nodes on power Doppler sonography tend to demonstrate high intranodal resistance and abnormal distribution of vascularity within a node. However, in our experience metastatic nodes from papillary carcinoma of the thyroid frequently demonstrate low intranodal resistance and some do not demonstrate the presence of any abnormal vascularity within. We were therefore interested to document these features. MATERIALS AND METHODS: The grey scale and power Doppler sonograms of 21 metastatic nodes from papillary carcinoma of the thyroid were evaluated. The intranodal distribution of vessels and the intranodal vascular resistance of vessels was assessed and compared with the reported features of metastatic nodes from other head and neck primaries. RESULTS: A majority (17/20, 85%) of metastatic nodes from papillary carcinoma of the thyroid had a maximum resistance index (RI) and pulsatility index (PI) < 0.8 and 1.6, respectively. A majority of the nodes (16/21, 76%) demonstrated abnormal capsular vascularity within the nodes. CONCLUSION: Metastatic nodes from papillary carcinoma on power Doppler sonography frequently have low RI and PI and 24% demonstrate just prominent hilar vascularity similar to reactive nodes.

Adolescent↗
PubMed2001

'Pseudocystic' appearance of non-Hodgkin's lymphomatous nodes: an infrequent finding with high-resolution transducers.

AIMS: A pseudo-cystic appearance and posterior enhancement are previously reported to be diagnostic sonographic features of lymph node involvement in non-Hodgkin's lymphoma. This study was undertaken to determine whether these ultrasonic features remain with the use of high-resolution transducers. MATERIAL AND METHODS: A review of ultrasound examinations in 32 patients with proven lymphomatous cervical lymphadenopathy (27 non-Hodgkin's lymphoma, five Hodgkin's disease) was performed. A total of 95 lymph nodes were assessed for size, shape, posterior enhancement and internal architecture. All examinations were performed with the same high-resolution transducer and by the same sonologist. RESULTS: Lymphomatous nodes (irrespective of type) are frequently heterogeneous (68-86%), have a micronodular pattern (63-69%) and less commonly demonstrate posterior enhancement (9-26%). CONCLUSION: Using a high-resolution ultrasonic transducer, cervical nodes involved with lymphoma (irrespective of type) commonly demonstrate a heterogeneous micronodular pattern. The pseudocystic appearance of nodes with posterior enhancement in non-Hodgkin's nodes is seen infrequently.

Adolescent↗
PubMed2001

Dentascan in oral imaging.

In the past, dental disease and lesions involving the jaw were either evaluated by plain radiography or tomography. The advent of spiral computed tomography (CT) and DentaScan is changing the imaging trend. It is now not only used for pre-implant assessment but also in the diagnosis of lesions affecting the jaw. This pictorial review discusses the role of DentaScan in the various abnormalities that may affect the mandible and maxilla.

Ameloblastoma↗
PubMed2001

A prospective study of the effect of botulinum toxin A on masseteric muscle hypertrophy with ultrasonographic and electromyographic measurement.

We evaluated the effect of botulinum toxin A on masseteric muscle hypertrophy by using ultrasound and electromyography. Five patients (four with bilateral and one with unilateral masseteric muscle hypertrophy) were studied prospectively. In each patient, ultrasound-guided percutaneous intramuscular injection of botulinum toxin A was carried out. The change in muscle bulk was evaluated using serial ultrasonography and the electrical activity was assessed with electromyography. All five patients (nine hypertrophic muscles) showed a good response, with the maximal effect of a 31% reduction in muscle bulk seen 3 months after treatment. The effect remained stable one year after injection for six of the hypertrophic muscles, whereas three muscles needed a second injection to maintain the atrophy. This preliminary prospective study suggests that botulinum toxin A is a safe alternative method of treating masseteric muscle hypertrophy. However, the effect may be temporary and further intramuscular injection may be required to maintain atrophy.

Adolescent↗
PubMed2001

Fibromatosis of the head and neck region.

OBJECTIVE: Five cases of head and neck fibromatosis were analyzed. The imaging and pathologic findings, surgical management, and clinical outcome were discussed. STUDY DESIGN AND SETTING: A retrospective study of 5 adult head and neck fibromatosis cases, evaluating long-term follow-up results of conservative treatment. RESULTS: The 5 patients (2 male and 3 female) ranged in age from 16 to 51 years. The lesion size ranged from 1 to 8 cm. Four cases had limited surgical resection; 1 case was followed only. One of the surgically treated cases had a recurrence that was irradiated. All patients were well for a follow-up period of 2 to 8 years. CONCLUSION: Aggressive excision of head and neck fibromatosis cannot be achieved easily. Vigilant follow-up with or without conservative surgical excision achieves good disease control. Low dose radiotherapy can be used for inoperable cases. SIGNIFICANCE: Judicious conservative treatment should be attempted for head and neck fibromatosis to achieve optimal functional preservation.

Adolescent↗