Biomedical subjects

Xiangquan Kong

Publications and source records attributed to Xiangquan Kong.

5 recordsLinked to original sources

PubMed2006

Noninvasive detection of coronary artery stenosis using 16-slice spiral CT: a comparison with selective X-ray coronary angiography.

The role of 16-slice spiral CT was evaluated in the diagnosis of coronary stenosis, with selective X-ray coronary angiography (SCA) serving as the reference standard. Sixty-five patients who were suspected of having coronary heart disease, without percutaneous transluminal coronary angioplasty or coronary bypass-grafting, were investigated using 16-slice CT. Eight patients with pre-scan heart rate of more than 80 beats/min were given beta-blockers. After the retrospectively ECG-gated axial imaging reconstruction, volume redering (VR), multi-planar reconstruction (MPR), curved MPR and maximum intensity projection (MIP) were used to reconstruct. Every segment of coronary artery with a diameter > or = 1.5 mm was assessed, and the presence on CT with a stenosis exceeding 50% diameter reduction was compared with that on SCA. The reasons which lead to some segments unevaluable were analysed. Compared with SCA, 93% coronary segments and 94% main branches were evaluable. Residual cardiac motion artifacts, severe calcification and poor opacification made 58%, 28% and 14% of the remaining 60 segments unevaluable respectively. Without routine administration of beta-blockers, good coronary imaging quality can be acquired using 16-slice spiral CT. It is a reliable noninvasive method for detection of obstructive coronary artery disease.

Adult↗

PubMed2005

MR features of regenerative nodules and dysplastic nodules in the cirrhotic liver.

In order to study MR features of the regenerative nodule (RN) and dysplastic nodule (DN) of the cirrhotic liver, 26 cases of cirrhotic liver with RNs and DNs, of which 8 cases accompanied with hepatocellular carcinoma, were subjected to MRI. Eighteen of 26 cases underwent additional enhanced MRI with administration of Gd-DTPA on T1WI and 10 of the 18 cases did additional SPIO (Feridex) enhancement on T2WI. Clinical data showed normal level of alpha-fetoprotein in 18 cases except 8 cases accompanied with HCC. The results showed that 12 cases had RNs with nodules measuring < 1 cm. The MR appearance of those RNs showed isointensity on T1WI and hypointensity on T2WI. The intensity of those RNs was isointense to the surrounding hepatic parenchyma on enhanced MRI with administration of Gd-DTPA or SPIO. Among the 14 cases of DNs, 8 cases had nodules measuring 1-3 cm in size and 6 had macroregenerative nodule measuring > 3 cm. In 8 cases with DNs measuring 1-3 cm in size, 5 cases appeared hyperintense on T1WI and hypointense on T2WI as well as the enhancement as that of nodules with < 1 cm in size; and the remaining 3 cases appeared hypointense on T1WI and hyperintense on T2WI, and were not isointense to the surrounding hepatic parenchyma on enhanced MRI but hyperintense on SPIO enhanced MRI. In 6 cases of macroregenerative nodule measuring > 3 cm in size, 2 cases appeared hyperintense to the surrounding hepatic parenchyma on T1, T2WI and enhanced MRI; 4 cases showed hyperintense on T1WI, and hypointense on T2WI and enhanced MRI. Sometimes, normal vessels were seen to pass through the surface of macroregenerative nodules. It was suggested that RNs of cirrhosis had features on MRI that usually allow distinction from hepatocellular carcinoma but not always from dysplastic nodules (DNs). A helpful distinction between HCC and DNs is that the latter are almost never hyperintense on T2WI. Additionally, low grade DNs appear hypointense on SPIO enhanced MRI.

Carcinoma, Hepatocellular↗

PubMed2004

MRI features of intracranial primitive neuroectodermal tumors in adults: comparing with histopathological findings.

The MRI appearances of 7 adult patients with pathologically proven intracranial primitive neuroectodermal tumors (PNET) were retrospectively analyzed. The MRI features were compared with findings in pathology and surgery. In this group, the tumor masses were most commonly found in the semisphere of cerebrum and in the vermis of cerebellum. They were relatively large and 4 were in lobulated shape. All of them had well-defined margins. MR images showed the tumors to be mildly or obviously hypointense on T1-weighted images and hyperintense on T2-weighted images. Most masses had heterogeneous appearances with some cystic and necrotic areas. Intratumoral haemorrhage and focal calcification were occasionally seen. Mostly, there was no or only mild surrounding edema. Marked inhomogeneous contrast enhancement on MRI was seen in 6 cases except one. Two patients with multiple intracranial metastases were revealed on MR images. In this series, there was good correlation between MRI features and findings in pathology and surgery. These results showed that certain MRI features might suggest the diagnosis of intracranial PNET in adults. MRI is an effective technique to detect these tumors and is helpful to treatment planning and follow-up.

Adult↗

PubMed2003

Differential diagnosis of arachnoid cyst from subarachnoid space enlargement by phase-contrast cine MRI.

OBJECTIVES: To reveal the relationship of brain motion and cerebrospinal fluid (CSF) flow by phase-contrast cine MRI, and to evaluate this technique in differentiating between arachnoid cysts and subarachnoid space enlargement. METHODS: Using a phase-contrast cine MRI pulse sequence, we measured brain motion and CSF flow during the cardiac cycle in 10 healthy volunteers and 10 patients with MRI-suspected arachnoid cyst or subarachnoid space enlargement. CSF stroke volume curve was illustrated according to flow quantification, and time-signal intensity curve was traced. The two curves were compared. RESULTS: This study showed that brain motion was due to the volume difference between arterial and venous blood flow during a cardiac cycle, and thus drives CSF pulsation. Arachnoid cysts and subarachnoid space enlargement carried different curve patterns, demonstrating that phase-contrast MRI and flow quantification can be a useful and reliable technique for non-invasive evaluation of brain motion and CSF flow. CONCLUSION: Arachnoid cysts can be successfully differentiated using phase-contrast cine MRI from subarachnoid space enlargement.

Adult↗

PubMed2003

[Integrated methods for assessing auditory nerve-auditory pathway integrity].

OBJECTIVE: To evaluate the feasibility and value of integrated methods to assess auditory pathway integrity. METHOD: Twenty-four cases of bilateral profoundly-deafened individuals who were considered as the candidates of cochlear implantation were included in this study. Auditory pathway integrity from these candidates of cochlear implantation were assessed with the integrated methods established by our team, which consist of 5 categories including 1. audiological test; 2. radiological imaging study; 3. ear-canal electric audiometry; 4. response to sound in daily life; and 5. speech development. RESULT: Twenty-three candidates who meet the criteria of auditory nerve-auditory pathway integrity received cochlear implantation with improved hearing and speech development postoperatively. The remainder one of the 24 candidates was diagnosed as bilateral absence of auditory nerve. The fault of cochlear implantation was avoided. CONCLUSION: The integrated methods for assessing auditory pathway integrity is feasible and valuable. Auditory nerve-auditory pathway integrity should be considered and included as one of the most important criteria for cochlear implantation candidate.

Acoustic Stimulation↗