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V F Chong

Publications and source records attributed to V F Chong.

11 recordsLinked to original sources
PubMed1995

Case report: calcified stones in right-sided colonic diverticula stimulating gallstones.

Right-sided colonic diverticulosis, though unusual in the Western population, is common in the Orient. Calcified stones are rarely found within colonic diverticula. Standard textbooks of diagnostic radiology do not list calcified stones within caecal or ascending colonic diverticula as possible causes of calcification in the right hypochondrium or right iliac fossa. We present a patient with multiple laminated right-sided diverticular concretions mimicking gallstones. This possibility should be included in the differential diagnosis of gallstones or calcifications on the right side of the abdomen.

Cholelithiasis↗
PubMed1995

Magnetic resonance imaging and computed tomography features of nasopharyngeal carcinoma with maxillary sinus involvement.

Anterior spread of nasopharyngeal carcinoma (NPC) may infiltrate the maxillary sinus. In a prospective study of 114 patients comparing magnetic resonance imaging (MRI) and computed tomography (CT) in the staging of NPC, 10 (9%) patients were noted to have tumour infiltration of the maxillary sinuses. All of the patients except one had associated infiltration of the sphenoidal sinuses indicating advanced local spread. Computed tomography was excellent in outlining the extent of bony erosion and associated soft tissue mass within the antra. T1-weighted images could not demonstrate bony erosions directly although soft tissue extension into the sinuses could be clearly visualized. Both CT and MRI showed good demarcation between tumour and mucosal thickening within the maxillary sinus. Although MRI demonstrated soft tissue involvement more elegantly than CT, it did not appear to offer significantly more information that may affect clinical management.

Adult↗
PubMed1995

Comparing computed tomographic and magnetic resonance imaging visualisation of the pterygopalatine fossa in nasopharyngeal carcinoma.

In a prospective study comparing computed tomography (CT) and magnetic resonance imaging (MRI) in the staging of nasopharyngeal carcinoma (NPC), 17 (15%) patients were noted to have infiltration of the pterygopalatine fossa (PPF). The recognition of PPF abnormalities depends on the familiarity of the normal anatomy. CT and MRI appearances of the normal PPF in the remaining 97 (85%) patients were reviewed. The fossae were symmetrical and fat was seen in all MRI and in 95% of the CT scans. There was destruction of the pterygoid process in 10 (9%) patients and a further 10 patients showed erosion of the maxillary sinus. Superior infiltration from the PPF into the inferior orbital fissure was demonstrated in 7 (6%) patients. Lateral spread via the pterygopalatine fissure into the infratemporal fossa could be seen in 10 (9%) patients. The earliest indication of tumour infiltration of the PPF is the replacement of the normal fat content. Widening of the fossa and erosion of the bony margins are late signs. As expected, bony abnormality is best seen on CT. However, direct visualisation of tumour or replacement of fat is more elegantly demonstrated on T1-weighted MRI.

Humans↗
PubMed1995

Imaging thoracic malignancy.

The radiological detection of a thoracic neoplasm is often a straightforward exercise. The differentiation of a benign from a malignant lesion is much more challenging and has met with limited success. Computed tomography (CT) may help to differentiate a benign nodule from a malignant lesion but magnetic resonance imaging (MRI) plays no part in the evaluation of a coin lesion. Recent studies indicate MRI to be superior in the staging of bronchogenic carcinoma with reference to chest wall infiltration, mediastinal invasion and vascular involvement. It is now known that in the staging of nodal metastasis, both CT and MRI are less sensitive and specific than previously believed. CT remains the method of choice in the detection of pulmonary metastatic disease. Biopsy under imaging control has contributed significantly in the management of patients with thoracic malignancy. Both CT and MRI are used in the monitoring of patients under treatment. The postlobectomy or pneumonectomy space is best evaluated by MRI. This paper reviews the current status of imaging in the detection, staging and follow-up of patients with thoracic malignancy.

Humans↗
PubMed1995

Failed back surgery syndrome: differentiating epidural fibrosis and recurrent disc prolapse with Gd-DTPA enhanced MRI.

The failed back surgery syndrome (FBSS) is a difficult diagnostic problem. Two of the more common causes of FBSS are epidural fibrosis and recurrent disc prolapse. Forty-five gadolinium-diethylenetriaminepenta-acetic acid (Gd-DTPA) enhanced magnetic resonance (MR) scans were performed on 43 patients to evaluate the effectiveness in differentiating recurrent disc prolapse from epidural fibrosis. Operative findings were available in 11 patients and they confirmed the pre-operative radiological diagnosis of recurrent disc prolapse in 6, epidural fibrosis in 4 and facet joint hypertrophy in 1 patient. Although the number of surgically verified cases is small, our initial experience of 100% diagnostic accuracy reflects the tremendous potential of this investigative tool. Separating epidural fibrosis from recurrent disc prolapse is crucial as patients with the former are expected to benefit from further surgery. Patients with epidural fibrosis, on the other hand, generally do not gain relief from another operation.

Adult↗
PubMed1995

MRI findings in failed back surgery syndrome.

The failed back surgery syndrome (FBSS) is a difficult diagnostic problem both clinically and radiologically. Forty-three patients were evaluated prospectively with magnetic resonance imaging (MRI) and forty-five scans were obtained. Fifteen patients (33%) showed recurrent disc prolapse; 15 (33%) patients postoperative epidural fibrosis; 8 (18%) both recurrent disc prolapse and epidural scarring; 4 (9%) patients spinal stenosis, 2 whom also had both epidural fibrosis and recurrent disc prolapse; 2 (4%) normal scans; 2 (4%) patients arachnoiditis and 1 (2%) patient postoperative pseudomeningocoele formation. Gadolinium-diethylenetriaminepenta-acetic acid (Gd-DTPA)-enhanced MRI was particularly helpful in differentiating recurrent disc prolapse and epidural fibrosis. Surgical findings in 11 patients were available. MRI correctly predicted recurrent disc prolapse in 6 patients, epidural fibrosis in 4 patients and spinal stenosis in 1 patient illustrating the value of this modality in the evaluation of FBSS.

Adult↗
PubMed1994

Ultrasonographic hepatic pseudolesions: normal parenchyma mimicking mass lesions in fatty liver.

Fatty hepatic infiltration is usually diffuse but may be patchy or localized. Occasionally, focal areas of normal parenchyma in an otherwise diffuse fatty liver may mimic mass lesions. Typically, these pseudolesions appear as echopoor areas against a background of bright echoes due to fatty infiltration. We report five cases of sonographic pseudolesions with computed tomographic (CT) correlation. Sonographic features that may differentiate these pseudolesions from true abnormalities include their characteristic location in the quadrate lobe, nondisplacement of blood vessels and sometimes their straight-edged appearance of geometric pattern. When these features are present, further investigation is unnecessary. However, patchy foci of normal parenchyma may pose a difficult diagnostic problem which may necessitate computed tomography and biopsy for definitive diagnosis.

Adult↗
PubMed1993

Subarachnoid spaces in infants and young children.

In computed tomography of young children, the frontal subarachnoid spaces were sometimes noted to be prominent in scans which were otherwise normal. These apparently enlarged spaces raise the suspicion of possible subdural hygromas. The objective of this study is to show the trend and variability of the intracranial subarachnoid spaces, especially the frontal subarachnoid spaces with age in children. Computed tomographic scans of 39 children up to five years of age with normal head scans were assessed for sizes of the subarachnoid spaces which were subjectively graded from I to V. Grade I is not visible while grade V is borderline enlargement. The sizes of the subarachnoid spaces were found to be more variable in those below the age of two years, with a tendency to be larger compared to older children. Based on these observations, prominent subarachnoid spaces in those below the age of two years should be considered a normal variant. A diagnosis of subdural hygroma must, therefore, be made with caution.

Brain Neoplasms↗
PubMed1993

Cholangiocarcinoma complicating ulcerative colitis.

A case of cholangiocarcinoma complicating ulcerative colitis in a young female Chinese is presented. The interval between the diagnosis of ulcerative colitis and development of bile duct carcinoma was seven years which is relatively short. An irregular stricture of the common bile duct associated with dilatation of the biliary tree and distension of the gallbladder were recognised at endoscopic retrograde cholangiopancreaticogram (ERCP). The clue to the diagnosis was a previous history of chronic diarrhoea. Ulcerative colitis is an uncommon disease in the Chinese population. Cholangiocarcinoma is a recognised uncommon complication.

Adult↗
PubMed1993

Familial Behçet's syndrome with intestinal involvement--case reports and a review of the literature.

Behçet's syndrome is a rare multisystem disorder. The occurrence in families although well recognised is uncommon. The mode of inheritance, however, has not been elucidated. Sixty-one cases of familial disease have been documented to date. There was only one previous report on familial Behçet's syndrome with gastrointestinal involvement. This paper reports two cases of Behçet's syndrome with gastrointestinal involvement in a Malaysian woman of Chinese ethnic origin and her child. The mother satisfied three major criteria (oral ulcers, genital ulcers and erythema nodosum) and one minor criterion (gastrointestinal involvement). Her son satisfied two major criteria (oral and genital ulcers) and three minor criteria (intestinal involvement, central nervous manifestation and a positive family history). The radiological and pathological features of the gastrointestinal lesions in both patients resembled those of Crohn's disease. The literature on Behçet's syndrome is reviewed.

Adult↗