Fuzzy C-means clustering of magnetic resonance imaging on apparent diffusion coefficient maps for predicting nodal metastasis in head and neck cancer.

OBJECTIVE: The present study evaluated and analyzed apparent diffusion coefficients (ADCs) from partitions through a fuzzy C-means (FCM) technique for distinguishing nodal metastasis in head and neck cancer. METHODS: MRI studies of 169 lymph node lesions, dissected from 22 patients with a histopathologically confirmed lymph node status, were analyzed using in-house software developed using MATLAB(®) (The MathWorks(®) Inc., Natick, MA). A radiologist manually contoured the lesions, and ADCs for each lesion were divided into two (low and high) and three (low, intermediate and high) partitions by using the FCM clustering algorithm. RESULTS: The results showed that the low-value ADC clusters were more sensitive (95.7%) in distinguishing malignant from benign lesions than the whole-lesion mean ADC values (78.3%), while retaining a high specificity (approximately 90%). Moreover, receiver-operating characteristic curves demonstrated that the low-value ADC clusters used as a predictor of malignancy for lymph nodes could achieve a higher area under the curve (0.949 and 0.944 for two and three partitions, respectively). CONCLUSION: The segmentation by ADC values of lesions through the FCM technique enables the efficient characterization of the lymph node pathology and can help distinguish malignant from benign lymph nodes. ADVANCES IN KNOWLEDGE: Tumour heterogeneity may degrade the prediction of metastatic lymph nodes that involves using mean region-of-interest ADC values. The clustering of ADC values in lesions by using FCM can improve the diagnostic accuracy of nodal metastasis and reduce interreader variance.

Interleukin-6 as a Prognostic Biomarker in Ruptured Intracranial Aneurysms.

BACKGROUND: Interleukin-6 (IL-6), a proinflammatory cytokine, was found to surge in the cerebral spinal fluid after aneurysmal subarachnoid hemorrhage (SAH). We hypothesized that the plasma level of IL-6 could be an independent biomarker in predicting clinical outcome of patients with ruptured intracranial aneurysm. METHODS: We prospectively included 53 consecutive patients treated with platinum coil embolization of the ruptured intracranial aneurysm. Plasma IL-6 levels were measured in the blood samples at the orifices of the aneurysms and from peripheral veins. The outcome measure was the modified Rankin Scale one month after SAH. Multiple logistic regression analyses were used to evaluate the associations between the plasma IL-6 levels and the neurological outcome. RESULTS: Significant risk factors for the poor outcome were old age, low Glasgow Coma Scale (GCS) on day 0, high Fisher grades, and high aneurysmal and venous IL-6 levels in univariate analyses. Aneurysmal IL-6 levels showed modest to moderate correlations with GCS on day 0, vasospasm grade and Fisher grade. A strong correlation was found between the aneurysmal and the corresponding venous IL-6 levels (ρ = 0.721; P<0.001). In the multiple logistic regression models, the poor 30-day mRS was significantly associated with high aneurysmal IL-6 level (OR, 17.97; 95% CI, 1.51-214.33; P = 0.022) and marginally associated with high venous IL-6 level (OR, 12.71; 95% CI, 0.90-180.35; P = 0.022) after adjusting for dichotomized age, GCS on day 0, and vasospasm and Fisher grades. CONCLUSIONS: The plasma level of IL-6 is an independent prognostic biomarker that could be used to aid in the identification of patients at high-risk of poor neurological outcome after rupture of the intracranial aneurysm.

Efficiency of three-dimensional Doppler ultrasonography in assessing nodal metastasis of head and neck cancer.

The aim of this study was to assess the clinical usefulness of three-dimensional (3D) color Doppler ultrasonography with a novel predictive model in the detection of cervical metastasis of untreated head and neck squamous cell carcinoma patients. We assessed cervical lymph node metastasis in 52 head and neck squamous cell carcinoma patients by 3D color Doppler ultrasonography, magnetic resonance imaging, and [(18)F] fluorodeoxyglucose positron emission tomography with computed tomography. Pathologic analysis was used as the gold standard for evaluation of these imaging modalities. The rate of correct N staging was 84.6% on ultrasonography, 55.8% on magnetic resonance imaging, and 71.2% on positron emission tomography/computed tomography. On a level-by-level basis, the ultrasonography had 78.9% sensitivity, 99.0% specificity, 93.8% positive predictive value, 96.0% negative predictive value, and 95.7% accuracy. It also showed the highest agreement to histology results as compared with magnetic resonance imaging and positron emission tomography/computed tomography (kappa value = 0.832, 0.506, and 0.537, respectively). 3D Doppler ultrasonography with our prediction model provides a rapid, low-cost, noninvasive, and reliable method with low inter-observation variations for detecting neck metastasis of head and neck squamous cell carcinoma patients.

Intracranial venous hemodynamics and rupture of cerebral aneurysm.

Many uncertain and inconsistent etiologies of cerebral aneurysmal rupture including a wide spectrum of factors have been reported. Our recent observation discloses the potential new factor of cerebral aneurysm rupture with cerebral venous pressure gradient. We retrospectively reviewed 52 cases treated with coil embolization with or without cerebral aneurysmal rupture. Seventeen males and 30 females were recruited in this study. Quantitative color-coded cerebral angiography was performed during coil therapeutic procedures to measure cerebral venous circulation. Ruptured cases had shorter and symmetrical cerebral venous circulation time (P <0.05). In addition, an asymmetrical venous outflow pattern was critical for aneurysmal rupture. Non-ruptured cases tended to have slower and asymmetrical cerebral venous circulation compared with rupture cases. Symmetrical and shorter cerebral venous circulation in the dysplasia venous outlet may be a potential new factor for cerebral aneurysm rupture.

Time sensitivity factor of single pulmonary nodule: a new cancer characteristic metabolic parameter by (18) F-FDG PET.

OBJECTIVE: To calculate the time sensitivity factor (S) for discriminating the solitary pulmonary nodule (SPN) by FDG PET at different time points. METHODS: The multiple time-point FDG PET images from 41 patients for evaluating SPN seen on chest X-ray or CT were prospectively analyzed to calculate and evaluate S against the gold standard of tissue histology (n = 38) or long term clinicoradiographic follow-up (n = 3). The maximal standardized uptake values (SUV) at the 3 hourly time points were measured. The S was calculated using S = d{ln⁡(SUV)}/d{ln⁡(t)} at 3 different time intervals. ROC analysis of the S parameters was performed to evaluate the optimal cut-off value and their accuracy in classifying the SPN. RESULTS: The SUV in malignant SPN was higher than the corresponding value in benign lesions at all 3 hourly time points (P < 0.003). The S parameters using 3 different time intervals all significantly separated the two groups (P < 0.0005) with an optimal cut-off point near the theoretical value of zero with a high sensitivity of 100% and specificity of 86%. CONCLUSION. The S can be calculated for SPNs using multiple time-point FDG PET, providing a tumor characteristic metabolic parameter with high discrimination power using a simple positive value representing malignancy.

Full-endoscopic interlaminar removal of chronic lumbar epidural hematoma after spinal manipulation.

BACKGROUND: Spinal manipulation is widely used for low back pain treatments. Complications associated with spinal manipulation are seen. Lumbar epidural hematoma (EDH) is one of the complications reported in the literature. If lumbar chronic EDH symptoms are present, which are similar to those of a herniated nucleus pulposus, surgery may be considered if medical treatment fails. Percutaneous endoscopic discectomy utilizing an interlaminar approach can be successfully applied to those with herniated nucleus pulposus. We use the same technique to remove the lumbar chronic EDH, which is the first documented report in the related literature. METHODS: We present a case with chronic lumbar EDH associated with spinal manipulation. Neurologic deficits were noted on physical examination. We arranged for a full-endoscopic interlaminar approach to remove the hematoma for the patient with the rigid endoscopy (Vertebris system; Richard Wolf, Knittlingen, Germany). RESULTS: After surgery, the patient's radiculopathy immediately began to disappear. Magnetic resonance imaging (MRI) follow-up 10 days after the surgery revealed no residual hematoma. No complications were noted during the outpatient department follow up. CONCLUSIONS: Lumbar EDH is a possible complication of spinal manipulation. Patient experiencing rapidly progressive neurologic deficit require early surgical evacuation, while conservative treatment may only be applied to those with mild symptoms. A percutaneous full-endoscopic interlaminar approach may be a viable alternative for the treatment of those with chronic EDH with progressive neurologic deficits.

Hepatic inflammatory pseudotumor mimicking hepatocellular carcinoma.

Inflammatory pseudotumor of the liver is a rare tumor. It has variable clinical presentations and image findings. It can mimic benign or malignant hepatic tumors, and may be difficult to diagnose. We present a case in which a hepatic inflammatory pseudotumor was misdiagnosed as hepatocellular carcinoma because the tumor presented a typical enhancing profile and morphology of hepatocellular carcinoma on computed tomography, and the patient had liver cirrhosis. However, a thicker tumor capsule than that of typical hepatocellular carcinoma was noted while reviewing the computed tomography images. A capsule of inflammatory pseudotumor thicker than that of hepatocellular carcinoma has never been reported in the literature before, and could be an important diagnostic clue to differentiate inflammatory pseudotumor from hepatocellular carcinoma.

Efficacy of transarterial chemoembolization for hepatocellular carcinoma in interlobar watershed zone of liver: comparison of unilateral and bilateral chemoembolization.

PURPOSE: To evaluate the treatment efficacy of unilateral versus bilateral transarterial chemoembolization for hepatocellular carcinoma (HCC) based on whether the tumor is located across the Cantlie line within the watershed zone of the liver. MATERIALS AND METHODS: Seventy-seven patients with 87 HCCs located in the watershed zone who underwent complete chemoembolization (unilateral, n = 57 [74%]; bilateral, n = 20 [26%]) were included. Tumors located in the watershed zone were further divided into two groups: tumors across the Cantlie line (type A) and tumors not across the line (type B). Comparison of treatment outcomes of unilateral or bilateral chemoembolization for the two groups was performed. The tumor viability (ie, presence of viable component or tumor progression) and position of the viable component on follow-up computed tomography was recorded. RESULTS: Tumor viability rates for type A tumors in the unilateral and bilateral chemoembolization groups were 52.2% and 11.1%, respectively; for type B tumors, they were 23.7% and 11.8%, respectively. The tumor viability rate of type A tumors was significantly higher in the unilateral chemoembolization group than in the bilateral chemoembolization group (P = .05), but there was no significant difference for type B tumors (P > .05). CONCLUSIONS: The tumor viability rate of HCC tumors across the Cantlie line was higher with unilateral chemoembolization group than with bilateral chemoembolization. In patients with HCC across the Cantlie line, embolization of bilateral hepatic arteries may achieve better treatment efficacy.

Acute cerebral infarction masked by a brain tumor.

We report on an 81-year-old man who presented with left limbs weakness and was brought to the emergency room where a brain computed tomography revealed a tumor at the right parasellar region. The patient was admitted to the neurosurgery department, and the symptoms were thought to be due to the tumor mass effect. The final diagnosis turned out to be acute ischemic infarction with an incidentally found brain tumor following angiography and magnetic resonance imaging.

Local intra-arterial thrombolysis with urokinase for acute ischemic stroke before and after the approval of intravenous tissue plasminogen activator treatment in Taiwan.

BACKGROUND: Local intra-arterial thrombolysis (LIT) has been previously suggested as an effective therapy for acute ischemic stroke. In this study, we describe our experience of using LIT for the treatment of Taiwanese patients with ischemic stroke at different vascular locations, before and after Alteplase was approved as a first-line treatment in Taiwan. The criteria required for the initiation of LIT have become more stringent after the approval of Alteplase (AA). METHODS: A retrospective analysis of medical records was conducted for 20 ischemic stroke patients treated with LIT; including 10 patients treated before and 10 patients treated after AA (we did not treat any of the patients in this study with AA). Urokinase was used for LIT treatment. Outcome measures included patient demographics, clinical characteristics, and clinical outcomes before and after LIT. Clinical outcomes were evaluated using four different stroke scales. RESULTS: The median National Institutes of Health stroke scale score (NIHSS) before treatment was reported to be 19.2 (range: 8-30). After AA, only one patient who had an occluded internal carotid artery (ICA) was treated with LIT. Among the 20 patients, 11 (55%) (five before AA and six after AA) reported having favorable or good clinical outcomes within 3 months of treatment, whereas five reported having poor outcomes (three before AA and two after AA), and the rest four patients died following treatment (two before AA and two after AA). Arterial recanalization was reported as complete in 10 patients (50%; seven middle cerebral artery [MCA] and three basilar artery; six before AA and four after AA), as incomplete in four patients (20%; one MCA and three basilar artery; one before AA and three after AA), and it failed in the remaining six patients (30%; two MCA and four ICA; three before AA and three after AA). Five patients (one MCA and four ICA) in whom recanalization had failed reported having poor outcomes, including one ICA patient who subsequently succumbed to the illness. Intracranial hemorrhagic and intraventricular hemorrhage transformation occurred in three and two patients, respectively. A case of intraventricular hemorrhage transformation after AA was also reported. CONCLUSION: On the basis of our experience, we found that LIT was of limited value in patients with ICA occlusion before AA approval. After AA, the outcomes in acute stroke patients, who were receiving urokinase therapy and who were carefully selected on the basis of the site of occlusion, were improved.

The influence of I-131 therapy on FDG uptake in differentiated thyroid cancer.

OBJECTIVE: 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) [or PET/computed tomography (CT)] is more likely to show false-negative results when it is performed shortly after chemotherapy and/or radiotherapy because of "metabolic stunning". The present study aimed to evaluate the influence of I-131 therapy on FDG uptake and the detection of recurrence or metastasis of differentiated thyroid cancer (DTC). METHODS: We retrospectively enrolled 16 consecutive FDG-PET/CT studies which had been performed in patients with DTC with elevated thyroglobulin (TG) but negative I-131 whole-body scan. All studies were performed under L: -thyroxine suppression. The patients were divided into groups A and B for PET/CT performed within 4 months of I-131 therapy or no such therapy, respectively. Each lesion identified on PET/CT was characterized using a 5-point scale by visual analysis: 0 = definitely benign, 1 = probably benign, 2 = equivocal, 3 = probably malignant, and 4 = definitely malignant. The maximum standardized uptake value (SUV max) in each lesion was also measured for semiquantitative analysis. We compared the visual grading and SUV max of the lesion of highest FDG uptake between groups A and B. RESULTS: For visual analysis, group B had significantly more patients with an uptake score of 3 or 4 than group A (80% vs. 17%, P = 0.01). In addition, there were significantly more equivocal results from group A than from group B (67% vs. 10%, P = 0.02). If the patients with the highest uptake scores of 2, 3, and 4 were considered to be positive for local recurrence or metastasis, there would be no significant difference between the positive rates of groups A and B (83% vs. 90%, P = 0.7). However, the mean SUV max of positive results was significantly lower for group A than for group B (3.1 +/- 0.9 and 6.6 +/- 3.5, respectively, P = 0.02). CONCLUSIONS: The preliminary results suggested that FDG uptake in DTC may be negatively influenced by I-131 therapy within 4 months, resulting in lower FDG uptake and more equivocal results. Further studies are necessary to determine whether it is secondary to "metabolic stunning" caused by I-131 therapy.

Detection of suspicious malignant cervical lymph nodes of unknown origin: diagnostic accuracy of ultrasound-guided fine-needle aspiration biopsy with nodal size and central necrosis correlate.

OBJECTIVE: To assess the role of ultrasound-guided fine-needle aspiration biopsy (US-guided FNAB) in the diagnostic workup of suspicious malignant cervical lymph nodes in patients with palpable neck masses and without known primary cancer. The diagnostic accuracy of imaging morphologic criteria, including sizes and central necrosis for assessing suspicious malignant nodes, were also examined. METHODS: This is a retrospective study of 426 patients with palpable neck masses from an outpatient department evaluated with computed tomography, magnetic resonance imaging, or US. US-guided FNABs were performed in 102 patients with suspicious malignant cervical lymph nodes at a single institution. Cytologically positive lymph nodes (n = 12) were further validated with excisional biopsy. Negative lymph nodes (n = 90) were either excised (n = 10) or followed up by imaging studies for at least one year (n = 80). The diagnostic accuracy of the FNABs along with the imaging findings of nodal sizes and presence of central necrosis, which were classified by a consensus of 2 radiologists, were assessed. RESULTS: Twelve malignant nodes were detected with US-guided FANB with one false-positive and one false-negative result. The overall sensitivity, specificity, and accuracy for FNAB were 91.7%, 98.9%, and 98.0%, respectively. The sensitivity, specificity, and accuracy were 66.7%, 30.0%, and 34.3% for size criterion and 75.0%, 83.3%, and 82.3% for central necrosis criterion. CONCLUSIONS: The size of cervical lymph node does not appear to be an important imaging criterion for assessing suspicious malignant lymph nodes, compared with the criterion of central necrosis. US-guided FNAB is highly specific and sensitive in the diagnostic workup of suspicious malignant cervical lymph nodes in patients without known primary cancers.