Combined Evaluation of Noncontrast CT ASPECTS and CT Angiography Collaterals Improves Detection of Large Infarcts in Proximal Artery Occlusive Stroke.

BACKGROUND AND PURPOSE: Imaging may identify patients with very large infarcts who are unlikely to benefit from intra-arterial therapy. Although computed tomography (CT) is widely used, it suffers from poor sensitivity. We sought to evaluate whether combined evaluation of noncontrast CT (NCCT) and CT angiography (CTA) collaterals would improve the detection of large infarcts. METHODS: All patients with anterior circulation proximal artery occlusion and baseline CT, CTA, and magnetic resonance imaging (MRI) performed were identified. NCCT ASPECTS, CTA collateral score (CS), and diffusion-weighted imaging (DWI) lesion volume were determined. Receiver-operating characteristic analyses were performed to test the discrimination of NCCT ASPECTS 0-4, CTA malignant collaterals (CS = 0: absent collaterals in >50% of M2 territory), and the combination for DWI volume > 100 mL. RESULTS: Among 54 patients, mean age was 67 years; median NIHSS was 14. Occlusion locations were ICA terminus (18 [33%]), MCA M1 (20 [37%]), and M2 (16 [30%]). Median NCCT ASPECTS was 8; 8 (15%) had ASPECTS 0-4. Median CTA CS was 2; 9 (17%) were categorized as malignant. Median DWI lesion volume was 25 mL; 12 (22%) had lesions >100 mL. Individually, the CTA malignant collateral profile (98%) and NCCT ASPECTS 0-4 (100%) demonstrated high specificity for DWI lesion volume >100 mL, but had suboptimal sensitivity (both 67%). In the combined approach (CTA CS = 0 and/or NCCT ASPECTS ≤4), the sensitivity improved significantly to 92%, while maintaining high specificity (98%). CONCLUSIONS: Combined evaluation of NCCT ASPECTS and CTA collaterals identifies patients with infarcts >100 mL with high accuracy, and can improve patient selection using current CT techniques.

Characterization of Portal Vein Thrombosis (Neoplastic Versus Bland) on CT Images Using Software-Based Texture Analysis and Thrombus Density (Hounsfield Units).

OBJECTIVE: The purpose of this study was to investigate the role of CT texture analysis and thrombus density (measured in Hounsfield units) in distinguishing between neoplastic and bland portal vein thrombosis (PVT) on portal venous phase CT. MATERIALS AND METHODS: In this retrospective study, 117 contrast-enhanced CT studies of 109 patients were included for characterization of PVT. Assessment of PVT was performed by estimation of CT textural features using CT texture analysis software and measurement of attenuation values. For CT texture analysis, filtered and unfiltered images were assessed to quantify heterogeneity using a set of predefined histogram-based texture parameters. The Mann-Whitney U test and binary logistic regression were applied for statistical significance. ROC curves were used to identify accuracy and optimal cutoff values. RESULTS: Of the 117 CT studies, 63 neoplastic thrombi and 54 bland thrombi were identified on the images. The two most discriminative CT texture analysis parameters to differentiate neoplastic from bland thrombus were mean value of positive pixels (without filtration, p < 0.001) and entropy (with fine filtration, p < 0.001). Mean thrombus density values could also reliably distinguish neoplastic (81.39 HU) and bland (32.88 HU) thrombi (p < 0.001). The AUCs were 0.97 for mean value of positive pixels (p < 0.001), 0.93 for entropy (p < 0.001), 0.99 for the model combining mean value of positive pixels and entropy (p < 0.001), 0.91 for thrombus density (p < 0.001), and 0.61 for the radiologist's subjective evaluation (p = 0.037). The optimal cutoffs values were 56.9 for mean value of positive pixels, 4.50 for entropy, and 54.0 HU for thrombus density. CONCLUSION: CT texture analysis and CT attenuation values allow reliable differentiation between neoplastic and bland thrombi on a single portal venous phase CT examination.

Parathyroid adenoma Localization.

BACKGROUND: Bilateral neck exploration is the gold standard for parathyroid adenoma localization in primary hyperparathyroidism. But surgeons do not have adequate experience for accurate surgical exploration and new methods are developed for surgery like unilateral exploration and minimally invasive surgery, thus, preoperative localization could reduces time and stress in surgical performance. METHOD: 80 patients with documented primary hyperparathyroidism and with raised serum calcium and parathyroid hormone (PTH) were selected. The results of ultrasonographic localization for each patient were compared with findings of surgery and 99m technetium sestamibi scintigraphy. Also variables such as preoperative serum calcium, PTH level and adenoma weight were compared between patients who had localized and non-localized adenoma with ultrasonography or Sestamibi scan. The data was compared with student's t-test. RESULTS: In a prospective diagnostic tests accuracy study, 80 patients with primary hyperparathyroidism were enrolled. Ultrasonography images detected enlarged parathyroid glands in 61 of 80 patients (76.3%) with sensitivity of 83.5% and positive predictive value (PPV) of 89.7%. Sestamibi scintigraphy detected adenoma in 63 patients (78.8%) with sensitivity of 85% and PPV of 91.3%. There was no significant deference between ultrasonography and scintigraphy in localization of adenomas. Both ultrasonography and scintigraphy used for determining localization, and they located 73 adenomas (91.3%) with sensitivity of 97.3% and PPV of 93.5%. CONCLUSION: Ultrasonography as an accurate method for localization of enlarged parathyroid glands in primary hyperparathyroidism, is comparable in overall utility with sestamibi scintigraphy. This study suggests a strategy for initial testing with one method, followed by the alternate imaging test if the first test happens to be negative.

Cytomegalovirus co-infection in patients with human immunodeficiency virus in Iran.

Serum samples from 201 HIV positive patients were collected to determine the seroprevalence of CMV infection in Iranian HIV infected patients during March 2004 until March 2005 using conventional ELISA kits. An antibody level of >1.1 Iu/ml was considered positive. The seroprevalence of CMV infection was 94%.The maximum prevalence of CMV antibody was seen in patients with unsafe sex and IDUs. Prevalence of CMV was much higher in patients with low socioeconomic status and low level of education. 83% of patients with CD4<100 were CMV seropositive. Our study showed that a significantly high prevalence of CMV in HIV positive patients in Iran. By increasing the level of education and socioeconomic status the prevalence of CMV infection decreased.

Seroprevalence of toxoplasmosis in HIV(+)/AIDS patients in Iran.

Toxoplasma gondii has arisen as an important opportunistic agent especially in the central nervous system and in advanced HIV disease can cause significant morbidity and mortality. This study was carried out to determine the seroprevalence of toxoplasmosis among HIV-positive patients in Iran. Blood samples were collected from 201 HIV-positive patients and anti-toxoplasma antibodies were detected by using conventional ELISA. An antibody titer of >3 IU/ml was considered positive. The majority of studied patients were male (male to female ratio: 5 to 1) with the mean age of 36 ± 1 yrs. The seroprevalence of toxoplasmosis in HIV-positive patients was 49.75%. The mean CD4 count in HIV patients with positive toxoplasma serology was 332.5 ± 22.4 cells/µl. Only 1% of the patients had IgM anti-toxoplasma antibodies and 10% of the patients had clinical toxoplasma encephalitis. The mean CD4 count in this group was 66.4 ± 15.5 cells/µl and there was a significant association between CD4 count and rate of toxoplasma encephalitis (P<0.001). Previous reports suggested that toxoplasma encephalitis could be prevented by appropriate chemoprophylaxis. In view of the relatively high prevalence of toxoplasma infection found among the HIV-infected patients in our study, we suggest that routine screening for toxoplasma should be undertaken for all HIV-infected patients in Iran.

Hepatitis-C and hepatitis-B co-infections in patients with human immunodeficiency virus in Tehran, Iran.

We carried out a study to determine the seroprevalence of HBV and HCV infections in HIV positive patients at a main referral center for HIV/AIDS in Iran. Serum samples from 201 HIV positive patients referring to a referral center for HIV/AIDS were analyzed for the presence of some hepatitis B (HBsAg, anti-HBc, anti-HBs) and Hepatitis C (anti-HCV) markers, during 2004- 2005. HBsAg was positive in 27 patients (13.4%), anti-HBc was positive in 60 patients (29.8%) and anti-HBs in 23 patients (11.4%). Anti-HCV Ab was positive in 135 of 201 (67.2%). HBV and HCV coinfection was observed in 73 of 201 (36.3%). The maximum prevalence of HBV-HIV and HCV-HIV coinfections were seen in intravenous drug users; 61.2% and 85.1%, respectively (P<0.0001). The minimum prevalence of HBV-HIV and HCV-HIV were seen in HIV patients' wife (HIV(+) patients who were infected by monogamous sexual contact with their HIV positive husband) both of them were 8% (P<0.0001). This study showed that HBV-HIV and HCV-HIV coinfections are significant in patients with HIV/AIDS in Iran. A greater relevance was observed in the association between HCV and HIV. This study suggests that it is necessary to investigate risk factors and risk groups for these infections in Iran.

Surgical options in the management of cystic duct avulsion during laparoscopic cholecystectomy.

BACKGROUND: Avulsion of cystic duct during laparoscopic cholecystectomy (LC) is not a common intraoperative complication, but may be encountered by any laparoscopic surgeon. Surgeons are rarely familiar with management of this condition. METHODS: Patients with gall stone related problems who were scheduled for LC at the minimal invasive surgery unit of a tertiary referral hospital during a 5 years period (April 2002-April 2007) were prospectively enrolled. RESULTS: 12 cases were identified (incidence: 1.15%). All 12 patients had gallbladder inflammation. Five patients had acute and seven patients had chronic cholecystitis. The avulsed cystic duct (ACD) was managed by clipping in 4, intracorporeal suturing in 3, converting to open surgery with suture ligation in 2, and lonely external drainage in 3 patients. Bile leakage had ceased within 3 days in 2, 14 days in one, and 20 days in the other patient. Bile volume increased gradually in one of the patients, which stopped only after endoscopic sphincterotomy (ES) at 25th postoperative day. No major late complication or mortality occurred. CONCLUSION: ACD during LC is a rare complication. Almost all standard methods of treatment yield to successful outcomes with low morbidity. According to the situation, ACD may be successfully managed laparoscopically. Available cystic stump remnant was clipped. Intracorporeal suture ligation was performed when short length of stump precluded clipping. Deeply retracted cystic duct with active bile leak led to conversion to open surgery. With minimal or no bile leak at ACD stump, closed tube drainage of sub-hepatic area was attempted. Persistent bile leak was assumed to be controlled by ES, successfully accomplished in one patient.

Comparative genomic hybridization (CGH) analysis of chromosomal aberrations in Iranian patients with invasive ductal carcinoma breast cancer.

INTRODUCTION: Breast cancer is one of the most common cancers in women; however, due to the complexity of chromosomal changes, limited data are available regarding chromosomal constitution. MATERIALS AND METHODS: In this study, Comparative Genomic Hybridization (CGH) was used on 16 Iranian patients diagnosed with invasive ductal breast carcinomas. RESULTS: 12 samples had abnormal CGH results (75%), including 21 types of chromosomal imbalance. The most prevalent were chromosomal gain of +1q, +17q, +8q and chromosomal loss of -13q. All three cases with DNA loss at chromosome 13q (-13q) had lymph node metastasis. CONCLUSIONS: CGH is able to detect chromosomal abnormalities which are difficult to identify by conventional cytogenetic techniques. More studies on a larger sample size may help to confirm or rule out any possible correlation between 13q monosomy and lymph node metastasis, which could result in establishing new strategies for prevention and early detection of invasive breast tumors.

The prevalence of exercise-induced bronchospasm in soccer player children, ages 7 to 16 years.

This study represents an attempt to determine the prevalence of exercise-induced bronchospasm among soccer player children. A total of 234 soccer player boys of all soccer schools from Shahr-Rey enrolled in this study. They did not have any history of a recent or chronic respiratory tract disease, a history of allergic diseases, and history of bronchodilator drugs consumption during the 24 hours prior to the study. Pulmonary function test (PFT) was performed for each participant before exercise and 6 and 15 minutes after playing soccer. The diagnosis of EIB was by a decrease in forced expiratory volume in 1 second (FEV1) by at least 10% and in peak expiratory flow rate (PEFR) by at least 15% with exercise challenge. If there was reduction in one parameter alone, the participants were considered as prone to EIB. Considering both FEV1 and PEFR the prevalence of EIB was 2.1% and 18.4% were prone to EIB. If FEV1 or PEFR tests were used as criteria for diagnosis of airway obstruction, the prevalence of EIB would be 6% and 15.8%, respectively. There was no significant difference between the post of players, family history of allergic disease and EIB in soccer players. This study suggests that at least 2.1% of soccer players will develop bronchospasm even if they do not have any history of asthma and allergy.