Unique genetic profiles from cerebrospinal fluid cell-free DNA in leptomeningeal metastases of EGFR-mutant non-small-cell lung cancer: a new medium of liquid biopsy.

Background: Leptomeningeal metastases (LM) are more frequent in non-small-cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations. Due to limited access to leptomeningeal lesions, the purpose of this study was to explore the potential role of cerebrospinal fluid (CSF) as a source of liquid biopsy in patients with LM. Patients and methods: Primary tumor, CSF, and plasma in NSCLC with LM were tested by next-generation sequencing. In total, 45 patients with suspected LM underwent lumbar puncture, and those with EGFR mutations diagnosed with LM were enrolled. Results: A total of 28 patients were enrolled in this cohort; CSF and plasma were available in 26 patients, respectively. Driver genes were detected in 100% (26/26), 84.6% (22/26), and 73.1% (19/26) of samples comprising CSF cell-free DNA (cfDNA), CSF precipitates, and plasma, respectively; 92.3% (24/26) of patients had much higher allele fractions in CSF cfDNA than the other two media. Unique genetic profiles were captured in CSF cfDNA compared with those in plasma and primary tissue. Multiple copy number variations (CNVs) were mainly identified in CSF cfDNA, and MET copy number gain identified in 47.8% (11/23) of patients was the most frequent one, while other CNVs included ERBB2, KRAS, ALK, and MYC. Moreover, loss of heterozygosity (LOH) of TP53 was identified in 73.1% (19/26) CSF cfDNA, which was much higher than that in plasma (2/26, 7.7%; P < 0.001). There was a trend towards a higher frequency of concomitant resistance mutations in patients with TP53 LOH than those without (70.6% versus 33.3%; P = 0.162). EGFR T790M was identified in CSF cfDNA of 30.4% (7/23) of patients who experienced TKI progression. Conclusion: CSF cfDNA could reveal the unique genetic profiles of LM and should be considered as the most representative liquid biopsy medium for LM in EGFR-mutant NSCLC.

Functional interaction of Junctophilin 2 with small- conductance Ca2+ -activated potassium channel subtype 2(SK2) in mouse cardiac myocytes.

AIM: Junctophilins (JPs), a protein family of the junctional membrane complex, maintain the close conjunction between cell surface and intracellular membranes in striate muscle cells mediating the crosstalk between extracellular Ca2+ entry and intracellular Ca2+ release. The small-conductance Ca2+ -activated K+ channels are activated by the intracellular calcium and play an essential role in the cardiac action potential profile. Molecular mechanisms of regulation of the SK channels are still uncertain. Here, we sought to determine whether there is a functional interaction of junctophilin type 2 (JP2) with the SK channels and whether JP2 gene silencing might modulate the function of SK channels in cardiac myocytes. METHODS: Association of JP2 with SK2 channel in mouse heart tissue as well as HEK293 cells was studied using in vivo and in vitro approaches. siRNA knockdown of JP2 gene was assessed by real-time PCR. The expression of proteins was analysed by Western blotting. Ca2+ -activated K+ current (IK,Ca ) in infected adult mouse cardiac myocytes was recorded using whole-cell voltage-clamp technique. The intracellular Ca2+ transient was measured using an IonOptix photometry system. RESULTS: We showed for the first time that JP2 associates with the SK2 channel in native cardiac tissue. JP2, via the membrane occupation and recognition nexus (MORN motifs) in its N-terminus, directly interacted with SK2 channels. A colocalization of the SK2 channel with its interaction protein of JP2 was found in the cardiac myocytes. Moreover, we demonstrated that JP2 is necessary for the proper cell surface expression of the SK2 channel in HEK293. Functional experiments indicated that knockdown of JP2 caused a significant decrease in the density of IK,Ca and reduced the amplitude of the Ca2+ transient in infected cardiomyocytes. CONCLUSION: The present data provide evidence that the functional interaction between JP2 and SK2 channels is present in the native mouse heart tissue. Junctophilin 2, as junctional membrane complex (JMC) protein, is an important regulator of the cardiac SK channels.

Bevacizumab plus chemotherapy for patients with advanced pulmonary adenocarcinoma harboring EGFR mutations.

PURPOSE: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) and bevacizumab plus chemotherapy were effective for EGFR-mutant patients. However, the appropriated treatment orders remained controvertible. We investigated the efficacy of treatment orders between bevacizumab plus chemotherapy and EGFR-TKIs for EGFR-mutant patients with advanced pulmonary adenocarcinoma. PATIENTS AND METHODS: This study involved 40 EGFR-mutant patients with advanced pulmonary adenocarcinoma who were treated with bevacizumab plus carboplatin and paclitaxel (Bev + CP) and EGFR-TKIs in different treatment orders or gemcitabine plus cisplatin (GP) in first-line setting. Seventeen patients were treated with Bev + CP and 10 cases with GP in first-line treatment. Thirteen patients received EGFR-TKIs after first-line Bev + CP regimen, while 13 patients were treated with first-line EGFR-TKIs. Progression-free survival (PFS), the response rate (ORR) and overall survival (OS) were evaluated. RESULTS: Median PFS of Bev + CP treatment was significantly longer in first-line than non-first-line settings (11.7 vs. 5.6 months, P = 0.003). Median OS was 37.8 months for EGFR-mutant patients with first-line Bev + CP followed by second-line EGFR-TKIs and 31.0 months for those with first-line EGFR-TKIs and non-first-line Bev + CP, respectively (P = 0.509). Median PFS was 11.7 (95% CI 10.6-12.8) months for Bev + CP group and 4.7 (95% CI 4.4-5.0) months for GP group with the hazard ratio of 0.17 (P = 0.001). ORR was 70.6 and 50.0% in the two groups, respectively (P = 0.415). However, there was no significant difference in median OS (33.7 vs 27.8 months, P = 0.293). CONCLUSIONS: First-line Bev + CP followed by EGFR-TKIs might possibly provide favorable prognosis for EGFR-mutant patients. Bev + CP regimen significantly prolonged PFS in first-line than non-first-line settings. These findings warrant further investigations.

A phase III randomised controlled trial of erlotinib vs gefitinib in advanced non-small cell lung cancer with EGFR mutations.

BACKGROUND: A phase III trial was conducted to compare the safety and efficacy of erlotinib with that of gefitinib in advanced non-small cell lung cancer harbouring epidermal growth factor receptor mutations in exon 19 or 21. METHODS: Eligible patients were randomised to receive erlotinib (150 mg per day) or gefitinib (250 mg per day) orally until disease progression or unacceptable toxicity. We aimed to determine whether erlotinib is superior to gefitinib in efficacy. The primary end point was progression-free survival. RESULTS: A total of 256 patients were randomised to receive erlotinib (N=128) or gefitinib (N=128). Median progression-free survival was not better with erlotinib than with gefitinib (13.0 vs 10.4 months, 95% confidence interval (CI) 0.62-1.05, P=0.108). The corresponding response rates and median overall survival were 56.3% vs 52.3% (P=0.530) and 22.9 vs 20.1 months (95% CI 0.63-1.13, P=0.250), respectively. There were no significant differences in grade 3/4 toxicities between the two arms (P=0.172). CONCLUSIONS: The primary end point was not met. Erlotinib was not significantly superior to gefitinib in terms of efficacy in advanced non-small cell lung cancer with epidermal growth factor receptor mutations in exon 19 or 21, and the two treatments had similar toxicities.

Economic analysis of continuous antibiotic prophylaxis for prevention of urinary tract infections in infants with high-grade hydronephrosis.

BACKGROUND: For infants with hydronephrosis, continuous antibiotic prophylaxis (CAP) may reduce urinary tract infections (UTIs); however, its value remains controversial. Recent studies have suggested that neonates with severe obstructive hydronephrosis are at an increased risk of UTIs, and support the use of CAP. Other studies have demonstrated the negligible risk for UTIs in the setting of suspected ureteropelvic junction obstruction and have highlighted the limited role of CAP in hydronephrosis. Furthermore, economic studies in this patient population have been sparse. OBJECTIVE: This study aimed to evaluate whether the use of CAP is an efficient expenditure for preventing UTIs in children with high-grade hydronephrosis within the first 2 years of life. STUDY DESIGN: A decision model was used to estimate expected costs, clinical outcomes and quality-adjusted life years (QALYs) of CAP versus no CAP (Fig. 1). Cost data were collected from provincial databases and converted to 2013 Canadian dollars (CAD). Estimates of risks and health utility values were extracted from published literature. The analysis was performed over a time horizon of 2 years. One-way and probabilistic sensitivity analyses were carried out to assess uncertainty and robustness. RESULTS: Overall, CAP use was less costly and provided a minimal increase in health utility when compared to no CAP (Table). The mean cost over two years for CAP and no CAP was CAD$1571.19 and CAD$1956.44, respectively. The use of CAP reduced outpatient-managed UTIs by 0.21 infections and UTIs requiring hospitalization by 0.04 infections over 2 years. Cost-utility analysis revealed an increase of 0.0001 QALYs/year when using CAP. The CAP arm exhibited strong dominance over no CAP in all sensitivity analyses and across all willingness-to-pay thresholds. DISCUSSION: The use of CAP exhibited strong dominance in the economic evaluation, despite a small gain of 0.0001 QALYs/year. Whether this slight gain is clinically significant remains to be determined. However, small QALY gains have been reported in other pediatric economic evaluations. Strengths of this study included the use of data from a recent systematic review and meta-analysis, in addition to a comprehensive probabilistic sensitivity analysis. Limitations of this study included the use of estimates for UTI probabilities in the second year of life and health utility values, given that they were lacking in the literature. Spontaneous resolution of hydronephrosis and surgical management were also not implemented in this model. CONCLUSION: To prevent UTIs within the first 2 years of life in infants with high-grade hydronephrosis, this probabilistic model has shown that CAP use is a prudent expenditure of healthcare resources when compared to no CAP.

Literature on the aetiology of hypospadias in the last 5 years: molecular mechanism and environmental factors.

Year-by-year, there has been an increasing number of literature on hypospadias, and most of them are mainly focused on two aspects, namely surgical techniques and aetiology, including the molecular mechanism and associated environmental factors. Surgical techniques and nursing levels are being continuously improved. However, in stark contrast, the study of aetiology still lags behind. Up to now, there is still no consensus on the aetiology of hypospadias, including the molecular mechanism and associated environmental factors. To obtain an overall and latest result on the aetiology, we reviewed published literature regarding the aetiology of hypospadias including the molecular mechanism and associated environmental factors in PubMed in the last 5 years. Thirty-seven studies on the aetiology of hypospadias including molecular mechanism and associated environmental factors were found, of which 25 were about associated environmental factors, and they were described according to the aspects of chemicals, parental characteristics, nutrition and hormones. The remaining studies were about the hormone-dependent phase of molecular mechanism, namely androgen-related genes and oestrogen-related genes. Furthermore, the various points of view were classified and discussed in detail.

Imaging well-differentiated hepatocellular carcinoma with dynamic triple-phase helical computed tomography.

To investigate the imaging appearance of well-differentiated hepatocellular carcinoma (HCC) on dynamic CT, a total of 38 histopathologically proven well-differentiated HCC were included in a retrospective study. We reviewed the contrast-enhanced dynamic CT of all 38 tumours for attenuation of each tumour in unenhanced scan, arterial-dominant and delayed portal venous phases. Our results showed that dynamic CT identified 26 (68.4%) out of the 38 lesions. The remaining 12 lesions were isodense compared with surrounding liver parenchyma in each dynamic CT phase. There was no statistically significant difference between the mean size of tumours detected by dynamic CT and that of tumours not detected by dynamic CT (p = 0.1). Of a total of 38 tumours, most were isodense (n = 19) or hypodense (n = 16) in unenhanced scan, mostly hyperdense (n = 18) or isodense (n = 15) in arterial-dominant phase and mostly isodense (n = 22) or hypodense (n = 15) in delayed portal venous phase. Enhancement of tumour was observed in 19 (50.0%) of 38 lesions. In conclusion, the ability of dynamic CT to detect well-differentiated HCC is poor, and negative CT findings cannot exclude the presence of well-differentiated HCC, especially if there is well-grounded clinical suspicion for HCC.

Partial and complete tear of the anterior cruciate ligament.

PURPOSE: To analyze MR direct and indirect signs for knees with anterior cruciate ligament (ACL) partial or complete tear. MATERIAL AND METHODS: According to documented MR direct and indirect signs for ACL tear, we retrospectively reviewed the incidence of those signs in 15 partial ACL tear and 17 complete ACL tear patients. The findings were also compared with duration of injury (less or more than 6 weeks, as acute or chronic stages). RESULTS: A residual straight and tight ACL fiber in at least one pulse sequence was more frequently detected in partial ACL tears. The empty notch sign, a wavy contour of ACL, bone contusion at lateral compartment and lateral meniscus posterior horn tear were significantly more frequently seen in complete tear cases. The posterior cruciate ligament angle in chronic complete ACL tear cases (109 degrees +/-20 degrees ) had a tendency to be less than in chronic partial ACL tear cases (119+/-18 degrees ). CONCLUSION: The empty notch sign, a wavy ACL, bone contusion, and posterior horn of lateral meniscus tears are suggestive of a complete ACL tear. A residual straight and tight ACL fiber seen in at least one image section is a helpful sign to diagnosis of partial ACL tear. In the acute ACL injury stage, a focal increase of the ACL signal intensity is more suggestive of a partial ACL tear.

Intravenous contrast-enhanced Doppler sonography and intra-arterial carbon dioxide-enhanced sonography in the assessment of hepatocellular carcinoma vascularity before and after treatment.

PURPOSE: To compare i.v. contrast-enhanced sonography (CEUS), power Doppler sonography (PDUS) and i.a. carbon dioxide-enhanced sonography (CO2US) in assessing hepatocellular carcinoma (HCC) vascularities before and after treatment. Differences between PDUS and CEUS with the aid of CO2US were also observed. MATERIAL AND METHODS: In all, 43 patients with 67 histologically proved HCCs were examined with PDUS, CEUS, and CO2US. Among these tumors, 36 were HCCs before treatment and 31 were HCCs treated by transcatheter arterial chemoembolization or percutaneous ethanol injection or a combination of these two treatments. CO2US was used as the gold standard when comparing the PDUS and CEUS. RESULTS: Of the 36 untreated HCC tumors, 20 (55.6%) were hypervascular compared with the liver parenchyma at PDUS, 28 (77.8%) at CEUS, 31 (86.1%) at the early phase of CO2US and 32 (88.9%) at the late phase of CO2US. Of the 31 post-treatment HCCs, 11 (35.5%) showed hypervascularity at PDUS, 25 (80.6%) at CEUS, 25 (80.6%) at the early phase of CO2US and 26 (83.9%) at the late phase of CO2US. CONCLUSION: CO2US was superior to CEUS and CEUS was superior to PDUS for the detection of tumor vascularity in both untreated and treated HCCs. The duration of enhancement at CEUS was shorter than at CO2US. The ability of CO2US to detect additional small tumors was not possible with PDUS and CEUS.

Effect of theophylline on airway inflammation in asthma.

AIM: To investigate whether low dose theophylline has an anti-inflammatory effect in asthma. METHODS: Nineteen asthmatic subjects were given 200 mg sustained-release theophylline preparation twice daily for 4 weeks. The mean serum concentration of theophylline was 7.9 mg/L. The percentage of eosinophils, EG2+ eosinophils, and the level of eosinophil cationic protein (ECP) in sputum pre- and post-administration were detected by Wright's stain, immunocytochemistry, and immuno-CAP system, and the symptom scores and lung function were evaluated as well. The above indices for 10 healthy subjects were regarded as control. RESULTS: Before using theophylline, sputum eosinophils, EG2+ eosinophils, and ECP in asthmatic group were much higher than those of healthy group. After four weeks administration, there were great decreases in percentage of total eosinophils (40 % +/- 17 % vs 29 % +/- 11 %, P < 0.01), activated (EG2+) eosinophils (28 % +/- 9 % vs 10 % +/- 8 %, P < 0.01) and in the concentration of sputum ECP [(373 +/- 206) vs (220 +/- 132) microg/L, P < 0.01]. The symptom scores decreased greatly (7.1 +/- 1.2 vs 5.4 +/- 1.6, P < 0.01). There was a marked increased in forced expiratory volume one second (FEV(1.0)) after administration (2.2 +/- 0.6 vs 2.4 +/- 0.5, P < 0.01). The FEV(1.0) % of asthmatic subjects after administration increased (60 % +/- 13 % vs 65 % +/- 13 %, P < 0.01), too. CONCLUSION: These results indicated that low dose theophylline had inhibitory action on airway inflammation in asthma with noticeable improvement of the patients' symptoms and lung function.

Paget's disease of the bone: a case report.

Paget's disease of bone is rare in Asia. We report a case of Paget's disease in a 58-year-old Taiwanese man who was admitted with a 3-month history of bilateral numbness in the buttock region. Laboratory data disclosed an elevated serum alkaline phosphatase level (510 U/L). Plain radiographs of the lumbar spine showed generalized increased density at the third lumbar vertebra, associated with cortical thickening, loss of cortico-cancellous definition, and increased anteroposterior diameter. The T1-weighted magnetic resonance image of the lumbar spine showed diffuse, heterogeneous low signal intensity at the third lumbar vertebral body, pedicle, laminae, and spinal process; these areas showed mixed high and low signal intensity on the T2-weighted image. Technetium-99m bone scan revealed abnormal uptake in the involved vertebra. Histologic examination of the third lumbar spinal process confirmed the diagnosis of Paget's disease of bone. The patient remained well during a follow-up period of 6 months.

Vertebral bone marrow perfusion evaluated with dynamic contrast-enhanced MR imaging: significance of aging and sex.

PURPOSE: To investigate blood perfusion of nonfractured, normal-appearing vertebral bodies with regard to age and sex. MATERIALS AND METHODS: Dynamic magnetic resonance imaging (160 images obtained in 80 seconds) was performed from T10 to L5 in 66 patients. Patients were assigned to three groups: group 1, those 50 years or younger without compression fracture; group 2, those older than 50 years without compression fracture; or group 3, those older than 50 years with compression fracture. Peak enhancement percentage and enhancement slope were determined from the time-intensity curve of normal (nonfractured) vertebral body. Comparisons were made between groups, and the effect of age and sex interaction was analyzed. RESULTS: Higher peak enhancement percentage was demonstrated for group 1 compared with group 2 (58.21 +/- 44.65 [SD] vs 21.88 +/- 14.77, P <.005). Group 1 women revealed a higher enhancement percentage compared with group 1 men (87.17 +/- 54.13 vs 38.16 +/- 21.69, P <.05), which significantly decreased in those older than 50 years (from 87.17 +/- 54.13 to 17.98 +/- 13.80, P <.005). For men, this decrease in those older than 50 years was not as pronounced (from 38.16 +/- 21.69 to 25.38 +/- 15.43, P >.05). Presence of compression fracture at other levels of the spine (group 3) was not associated with a different enhancement percentage for normal vertebrae. CONCLUSION: Rate of vertebral bone marrow perfusion revealed a significant decrease in subjects older than 50 years. Women demonstrated a higher marrow perfusion rate than men younger than 50 years and a more marked decrease than men older than 50 years.

Intra-arterial carbon dioxide-enhanced ultrasonogram of hepatocellular carcinoma treated by transcatheter arterial embolization and percutaneous ethanol injection therapy.

The purpose of this study was to investigate the value of carbon dioxide-enhanced ultrasonography (CO2-US) in the evaluation of viable hepatocellular carcinomas (HCC) which were treated by transcatheter arterial embolization (TAE), percutaneous ethanol injection (PEI), or a combination treatment (TAE and PEI). Forty-one patients with 66 HCC were included in the study. They underwent CO2-US and angiography were performed in all tumours after they were treated by TAE, PEI or a combination treatment. Forty-six tumours were positively enhanced by CO2-US and 40 of them were positive by angiography. These 46 tumours were proved to be viable tumours either by biopsy or by follow-up studies. The positive predictive value was 100% for CO2-US and 87.8% in angiography. Twenty tumours were negative by CO2-US and these were also negative by angiography. Carbon dioxide-enhanced ultrasonography is a more reliable method for detecting the viable portion of the treated HCC compared with conventional angiography.

Carbon dioxide enhanced ultrasonography of hepatic haemangiomas.

The purpose of this study was to characterize the imaging manifestations of carbon dioxide enhanced ultrasonography (CO2US) in hepatic haemangiomas. CO2US was performed for 52 haemangiomas in 25 patients and for 352 various hepatic nodules in 192 patients. Characteristic enhancement patterns for hepatic haemangiomas were noted. All 39 large haemangiomas (> 1 cm) demonstrated peripheral nodular enhancement in the early and parenchymal phases associated with delayed washout character (> 30 min). Centripetal fill-in of CO2 was noted in 82.1% of large haemangiomas. Two enhancing patterns were noted in 13 small haemangiomas (< 1 cm): peripheral nodular (69.2%) and homogeneous (30.8%). Delayed washout was also noted in all small haemangiomas. Centripetal fill-in of CO2 was hard to define in small haemangiomas. None of the other 352 hepatic nodules had the same imaging features. In conclusion we found that CO2US is valuable in differentiating hepatic haemangiomas from other liver tumours in clinically doubtful cases.

Laryngeal tuberculosis: a series of 46 patients.

BACKGROUND: The incidence of laryngeal tuberculosis is declining after the advent of anti-tuberculous drugs. The disease itself is changing according to our experience, too. The changing pattern is our interest. METHODS: A series of 46 cases of laryngeal tuberculosis seen in our institution between 1980 and 1995 were reviewed retrospectively to assess the various features of the disease. RESULTS: The results showed a mean age of 48 years and a sex ratio of 2:1. Hoarseness is the most frequent presenting symptom (80%), and sore throat (52%) is another important symptom. The frequent locations of lesions are the true cords (57%), epiglottis (39%), false cords (35%), arytenoids (24%) and posterior commissure (7%). Laryngeal tuberculosis was the most common initial working diagnosis before a definite pathological report was completed. In 85% of the patients the disease was transmitted by bronchogenic route, and in the others it was primary laryngeal tuberculosis. Laryngeal tuberculosis responds well to early treatment with anti-tuberculous chemotherapy. CONCLUSION: The clinical presentation of laryngeal tuberculosis is changing. It is necessary to detect the disease early to prevent the development of severe sequalae or mortality.

The value of ultrasound measurement of gallbladder wall thickness in predicting laparoscopic operability prior to cholecystectomy.

We prospectively analysed 51 consecutive cases who underwent laparoscopic cholecystectomy from June 1992 to February 1993. There were 35 cases of chronic cholecystitis and 16 cases of acute cholecystitis. All underwent pre-operative ultrasonography, complete blood cell count, liver function test and endoscopic retrograde cholangiopancreatography. Of those 44 had post-operative ultrasound within the first 2 d and again on the seventh day. In 35 cases of chronic cholecystitis, 31 of 32 cases with a pre-operative gallbladder (GB) wall thickness of less than 6 mm were successfully resected laparoscopically. All three cases with a GB wall thicker than 6 mm were converted to open cholecystectomy. In acute cholecystitis, the wall thickness of the laparoscopic cholecystectomy group ranged from 2 to 9 mm (average 4 mm) and the wall thickness of the conversion group was 4-7 mm (average 6 mm). Post-operative fluid accumulation was noted in 28 (63.6%) cases. There was no correlation between post-operative pyrexia, duration of post-operative pain, clinical complications and the presence of fluid accumulation in the GB fossa. However, of four cases with increasing fluid on the seventh day, three developed complications. We conclude that ultrasonography is valuable in chronic cholecystitis for selecting cases for laparoscopic cholecystectomy.

Carbon dioxide-enhanced ultrasonography of liver tumors.

CO2 gas-enhanced ultrasonography was performed in 37 patients (47 studies) for the purpose of detecting small tumors and evaluating differential diagnosis. With conventional ultrasonography, 62 lesions were identified in 25 patients with HCC, 13 tumors were identified in eight patients with hemangioma, and multiple tumors were found in four patients with metastatic adenocarcinoma. CO2-enhanced ultrasonography detected five additional hemangiomas, 12 additional nodules in HCC, and the same number of metastatic nodules. The patterns of CO2 enhancement were characterized as homogeneous, heterogeneous, rim, internal spotted, negative, and mixed (more than one pattern in one lesion). The rim enhancement pattern was found to be specific for hemangioma. The internal spotted enhancement pattern was found exclusively in HCC. All the lesions that demonstrated negative enhancement were treated HCC. All the metastatic tumors demonstrated the mixed rim and internal spotted enhancement pattern. We suggest that CO2-enhanced ultrasonography is a useful tool in detecting small liver tumors. It can also help in the differentiation among various hepatic tumors.

Intravenous double-dose contrast computed tomography in the diagnosis of spinal arteriovenous malformations: report of four cases.

Spinal IV double-dose computed tomography (DCT) followed by reformation imagings was performed on 4 patients. Three cases received double-dose contrast injections, one case received a conventional single dose contrast material. 'Dots' enhancement on axial CT scanning and 'vasculature-like' hyperdense enhancement on sagittal and coronal reformation imagings were found in four cases of spinal arteriovenous malformation (AVM). Two were at the cervical region and two at the thoracic level. Typical serpentine filling defects were noted in the myelogram of three cases of spinal AVM. One patient suffered from acute onset of paraplegia (case 2), requiring that she received immediate surgical intervention after DCT scanning without myelography. Time for the whole procedure lasted approximately 20 minutes. In addition DCT followed by reformation imaging may be used as a noninvasive preliminary screening procedure for spinal AVMs.