Wide-field angiography for diagnosis and follow-up of Eales disease: a case series / Angiografia de amplo campo para diagnóstico e monitoramento da doença de Eales: série de casos

ABSTRACT Wide-field angiography enables assessing peripheral areas with better quality and gives greater deep focus, which improves the image periphery. Some studies have proposed the usefulness of these angiographic systems in inflammatory diseases of the retina. However, few studies have evaluated this technique in Eales disease. We present a case series in which 5 eyes of 3 patients with Eales disease were evaluated by using retinal fluorescein angiography with 30º, 50º, and 150º lenses in a laser-scanning ophthalmoscope. These cases highlight the usefulness of wide-field fluorescein angiography in the diagnosis and follow-up of peripheral ischemic retinal areas in Eales disease, which enables better follow-up than possible with conventional fluorescein angiography images.

RESUMO A angiografia de campo amplo permite avaliar áreas periféricas com melhor qualidade e proporciona maior foco profundo, melhorando a imagem da periferia. Alguns estudos têm proposto a utilidade desses sistemas angiográficos nas doenças inflamatórias da retina. No entanto, poucos estudos avaliaram esta técnica na doença de Eales. Apresentamos uma série de casos em que 5 olhos de 3 pacientes com doença de Eales foram avaliados usando angiografia de fluoresceína da retina com lentes de 30º, 50º e 150º em um oftalmoscópio de varredura a laser. Esses casos destacam a utilidade da angiografia com fluoresceína de campo amplo no diagnóstico e no acompanhamento das áreas isquêmicas periféricas da retina na doença de Eales, permitindo um melhor acompanhamento do o possível com imagens por angiofluoresceinografia convencional.

Wide-field angiography for diagnosis and follow-up of Eales disease: a case series.

Wide-field angiography enables assessing peripheral areas with better quality and gives greater deep focus, which improves the image periphery. Some studies have proposed the usefulness of these angiographic systems in inflammatory diseases of the retina. However, few studies have evaluated this technique in Eales disease. We present a case series in which 5 eyes of 3 patients with Eales disease were evaluated by using retinal fluorescein angiography with 30º, 50º, and 150º lenses in a laser-scanning ophthalmoscope. These cases highlight the usefulness of wide-field fluorescein angiography in the diagnosis and follow-up of peripheral ischemic retinal areas in Eales disease, which enables better follow-up than possible with conventional fluorescein angiography images.

Radiolabeled GX1 Peptide for Tumor Angiogenesis Imaging.

Early and accurate detection of primary or metastatic tumors is of great value in staging, treatment management, and prognosis. Tumor angiogenesis plays an essential role in the growth, invasion, and metastatic spread of solid cancers, and so, is a promising approach for tumor imaging. The GX1 (CGNSNPKSC) peptide was identified by phage display library and has been investigated as a marker for human cancers. This study aims to evaluate the 99mTc-HYNIC-PEG4-c (GX1) as a biomarker for tumor imaging. Our results showed that GX1 specifically binds to tumor cells in vitro. SKMEL28 and MDA-MB231 cells achieved total binding peak at 60 min of incubation. For B16F10 and MKN45 cells, the total and specific binding were similar during all time points, while A549 cell line showed rapid cellular total uptake of the tracer at 30 min of incubation. Biodistribution showed low non-specific uptakes and rapid renal excretion. Melanoma tumors showed enhanced GX1 uptake in animal model at 60 min, and it was significantly blocked by cold peptide. The radiotracer showed tumor specificity, especially in melanomas that are highly vascularized tumors. In this sense, it should be considered in future studies, aiming to evaluate degree of angiogenesis, progression, and invasion of tumors.

Magnetic resonance imaging of tumor angiogenesis using dual-targeting RGD10-NGR9 ultrasmall superparamagnetic iron oxide nanoparticles.

OBJECTIVE: Using RGD10-NGR9 dual-targeting superparamagnetic iron oxide nanoparticles to evaluate their potential value in tumor angiogenesis magnetic resonance imaging (MRI) and the biodistribution in vitro and in vivo. MATERIALS AND METHODS: Dual-targeting RGD10-NGR9 ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles were designed and synthesized in our previous study. In vitro, prussian blue staining and phenanthroline colorimetry were conducted to evaluate binding affinity and adsorption of dual-targeting USPIO nanoparticles to αvß3-integrin/APN positive cells. In vivo, a xenograft mouse tumor model was used to evaluate the potential of the dual-targeting nanoparticles as an MRI contrast agent. After intravenous injection, the contrast-to-noise ratio (CNR) values of MR images obtained were calculated at predetermined time-points. The iron level was detected to access the biodistribution and plasma half-time. RESULTS: In vitro, dual-targeting USPIO nanoparticles bound to proliferating human umbilical vein endothelia cells with high specificity. In vivo, contrast MRI of xenograft mice using dual-targeting nanoparticles demonstrated a significant decrease in signal intensity and a greater increase in CNR than standard MRI and facilitated the imaging of tumor angiogenesis in T2*WI. In terms of biodistribution, dual-targeting USPIO nanoparticles increased to 1.83 times in tumor lesions as compared to the control. And the plasma half-time was about 6.2 h. CONCLUSION: A novel RGD10-NGR9 dual-targeting USPIO has a great potential value as a contrast agent for the identification of tumor angiogenesis on MRI, according to the high specific affinity in vitro and in vivo.

Evaluation of Magnetonanoparticles Conjugated with New Angiogenesis Peptides in Intracranial Glioma Tumors by MRI.

Angiogenesis plays a critical role in progression of malignant gliomas. The development of glioma-specific labeling molecules that can aid detection and visualization of angiogenesis can help surgical planning and improve treatment outcome. The aim of this study was to evaluate if two peptides (GX1 and RGD-GX1) linked to angiogenesis can be used as an MR-imaging markers of angiogenesis. MR imaging was performed in U87 glioblastoma-bearing NOD-SCID mice at different time points between 15 and 120 min post-injection to visualize particle distribution. GX1 and RGD-GX1 exhibited the highest accumulation in U87 glioblastoma at 120 min post i.v. administration. GX1-conjugated agents lead to higher decrease in transverse relaxation time (T 2) (i.e., stronger contrast enhancement) than RGD-GX1-conjugated agents in U87 glioblastoma tumor model. In addition, we tested if U87-IDH1R132 mutated cell line had different pattern of GX1 or RGD-GX1 particle accumulation. Responses in U87-IDH1WT followed a similar pattern with GX1 contrast agents; however, lower contrast enhancement was observed with RGD-GX1 agents. The specific binding of these peptides to human glioblastoma xenograft in the brain was confirmed by magnetic resonance imaging. The contrast enhancement following injection of magnetonanoparticles conjugated to GX1 peptide matched well with CD31 staining and iron staining.

Maternal Plasma Nerve Growth Factor at the 11+0-13+6 Weeks' Scan as a Potential Angiogenic Marker of Preeclampsia: A Pilot Study.

OBJECTIVE: The aim of this study was to determine the role of nerve growth factor (NGF) in the first-trimester screening for preeclampsia (PE). METHODS: Uterine artery Doppler (UtAD) was determined transvaginally. Maternal concentrations of NGF were assessed in 42 patients who subsequently developed PE and in 95 controls. Quantile and multivariate regression analyses were performed for the NGF and UtAD adjustment and expressed as the multiple of the median (MoM) of the unaffected group. Logistic regression analysis was conducted to identify the best model for the prediction of PE. RESULTS: The maternal plasma concentration of NGF exhibited a trend towards lower values in patients who subsequently developed early-onset PE (e-PE) compared to controls (10.7 vs. 38.2 pg/ml, respectively; p = not significant). The median MoM NGF in the all-PE, e-PE and control groups was 0.97 (95% CI 0.13-3.36), 0.62 (95% CI 0.16-2.19) and 1.00 (95% CI 0.20-2.94), respectively (p = not significant). The best predictors of PE were previous PE, chronic hypertension and UtAD. With a false-positive rate of 10%, the detection rates (DRs) of all-PE and e-PE were 38 and 50%, respectively. The addition of MoM NGF did not improve the DR of PE. CONCLUSION: First-trimester NGF tends to be lower in patients who subsequently develop e-PE.

A Novel Microvascular Flow Technique: Initial Results in Thyroids.

To evaluate the flow imaging capabilities of a new prototype ultrasound (US) image processing technique (superb micro-vascular imaging [SMI]; Toshiba Medical Systems, Tokyo, Japan) for depiction of microvascular flow in normal thyroid tissue and thyroid nodules compared with standard color and power Doppler US imaging.Ten healthy volunteers and 22 patients, with a total of 25 thyroid nodules, scheduled for US-guided fine needle aspiration were enrolled in this prospective study. Subjects underwent US examination consisting of grayscale, color and power Doppler imaging (CDI and PDI) followed by color and monochrome SMI and pulsed Doppler. SMI is a novel, microvascular flow imaging mode implemented on the Aplio 500 US system (Toshiba). SMI uses advanced clutter suppression to extract flow signals from large to small vessels and depicts this information at high frame rates as a color overlay image or as a monochrome map of flow. Two radiologists independently scored still images and digital clips for overall flow detection, vessel branching details and noise on a visual-analog scale of 1 (worst) to 10 (best).For the volunteers SMI visualized microvasculature with significantly lower velocity than CDI and PDI (P < 0.012). In all thyroid nodules, SMI demonstrated microvascular flow with significantly higher image scores and provided better depiction of the vessel branching details compared with CDI and PDI (P < 0.0001). Clutter noise was significantly higher in monochrome SMI mode than in the other modes, including color SMI (P < 0.001).The novel SMI mode consistently improved the depiction of thyroid microvascular flow compared with standard CDI and PDI.

PET-Based Human Dosimetry of the Dimeric αvß3 Integrin Ligand 68Ga-DOTA-E-[c(RGDfK)]2, a Potential Tracer for Imaging Tumor Angiogenesis.

UNLABELLED: Peptides containing the Arg-Gly-Asp (RGD) sequence have high affinity for αvß3 integrin receptors overexpressed in tumor cells. The objective of this research was to determine the biodistribution and estimate the radiation dose from (68)Ga-DOTA-E-[c(RGDfK)]2 using whole-body PET scans in humans. METHODS: Five healthy volunteers (2 women, 3 men; mean age ± SD, 37.2 ± 15.6 y; range, 28-65 y; mean weight, 79.2 ± 21.0 kg; range, 64-115 kg) were included. After intravenous injection of the tracer (198.3 ± 3.3 MBq), 3 successive whole-body (vertex to mid thigh) PET/CT scans at 3 time points (30, 60, and 120 min) were obtained on a 16-slice PET/CT scanner. The subjects did not void the bladder until the entire series of images was completed. Low-dose CT without contrast agent was used for anatomic localization and attenuation correction. OLINDA/EXM software was applied to calculate human radiation doses using the reference adult model. RESULTS: The highest uptake was in the urinary bladder, followed by the liver, kidneys, and spleen, in descending order. The critical organ was the urinary bladder wall. The mean effective doses (all subjects, men and women) were 34.1 ± 4.9, 31.0 ± 2.4, and 20.9 ± 5.2 µSv/MBq for the no-voiding, 2.5-h-voiding, and 1-h-voiding models, respectively. CONCLUSION: Of particular interest in this research was the visualization of the choroid plexus and ventricular system, which seems to be a characteristic of RGD-dimeric peptides. Measured absorbed doses and effective doses are comparable to other previously reported RGD-based radiopharmaceuticals labeled with (68)Ga and (18)F. Therefore, (68)Ga-DOTA-E-[c(RGDfK)]2 can safely be used for imaging integrin αVß3 expression.

Evaluation of GX1 and RGD-GX1 peptides as new radiotracers for angiogenesis evaluation in experimental glioma models.

Gliomas are the most common type among all central nervous system tumors. The aggressiveness of gliomas is correlated with the level of angiogenesis and is often associated with prognosis. The aim of this study is to evaluate the novel GX1 peptide and the heterodimer RGD-GX1 radiolabeled with technetium-99m, for angiogenesis detection in glioma models. Radiolabeling and radiochemical controls were assessed for both radioconjugates. In vitro binding studies in glioma tumor cells were performed, as well as biodistribution in SCID mice bearing tumor cells, in order to evaluate the biological behavior and tumor uptake of the radiocomplexes. Blocking and imaging studies were also conducted. MicroSPECT/CT images were acquired in animals with experimentally implanted intracranial tumor. Open field activity was performed to evaluate behavior, as well as perfusion and histology analysis. The radiochemical purity of both radiotracers was greater than 96 %. In vitro binding studies revealed rather similar binding profi le for each molecule. The highest binding was for RGD-GX1 peptide at 120 min in U87MG cells (1.14 ± 0.35 %). Tumor uptake was also favorable for RGD-GX1 peptide in U87MG cells, reaching 2.96 ± 0.70 % at 1 h p.i. with 47 % of blocking. Imaging studies also indicated better visualization for RGD-GX1 peptide in U87MG cells. Behavior evaluation pointed brain damage and histology studies confirmed actual tumor in the uptake site. The results with the angiogenesis seeking molecule (99m)Tc-HYNIC-E-[c(RGDfk)-c(GX1)] were successful, and better than with (99m)Tc-HYNIC-PEG4-c(GX1). Future studies targeting angiogenesis in other glioma and nonglioma tumor models are recommended.

Limitations of three-dimensional power Doppler angiography in preoperative evaluation of ovarian tumors.

BACKGROUND: This study describes the accuracy of three-dimensional power Doppler (3D-PD) angiography as secondary method for differential diagnosis of ovarian tumors. METHOD: Seventy-five women scheduled for surgical removal of adnexal masses were assessed by transvaginal ultrasound. Ovarian tumors were classified by IOTA simple rules and two three-dimensional blocks were recorded. In a second step analyses, a 4 cm(3) spherical sample was obtained from the highest vascularized solid area of each stored block. Vascularization index (VI), flow index (FI) and vascularization-flow index (VFI) were calculated. The repeatability was assessed by concordance correlation coefficient (CCC) and limits of agreement (LoA), and diagnostic accuracy by area under ROC curve. RESULTS: IOTA simple rules classified 26 cases as benign, nine as inconclusive and 40 as malignant. There were eight false positive and no false negative. Among the masses classified as inconclusive or malignant by IOTA simple rules, the CCCs were 0.91 for VI, 0.70 for FI, and 0.86 for VFI. The areas under ROC curve were 0.82 for VI, 0.67 for FI and 0.81 for VFI. CONCLUSIONS: 3D-PD angiography presented considerable intraobserver variability and low accuracy for identifying false positive results of IOTA simple rules.

Sonographic features of primary tumor as independent predictive factors for lymph node metastasis in papillary thyroid carcinoma.

PURPOSE: The aim of this research was to find the sonographic features of primary tumor as independent predictive factors for lymph node metastasis in papillary thyroid carcinoma. METHODS/PATIENTS: To facilitate the research, 514 patients with papillary thyroid carcinoma were divided into solitary and multifocal groups. In solitary group, thyroid lesions were divided into several subgroups by size, border, margin, echogenicity, echohomogeneity, calcification, vascularization, location, stiffness and Hashimoto's thyroiditis (HT) conditions. Then, univariable and multivariable analyses were performed to find the sonographic features of primary tumor as independent predictive factors for lymph node metastasis in papillary thyroid carcinoma. RESULTS: A significant difference of lymph node metastasis rate was found between multifocal and solitary groups (P < 0.05). In univariable analysis, size, vascularization and coexistence of HT were found to be statistically significant factors (P = 0.004, 0.118, 0.016). Multivariable analysis revealed that lymph node metastasis rate was mainly associated with size [odds ratio (OR) = 1.690, 95 % confidence interval (CI) 1.157-2.469] and coexistence of HT (OR = 0.441, 95 % CI 0.219-0.888). CONCLUSION: Preoperative sonographic features of primary tumor including the number, size and coexistence of HT were independent predictive factors for the state of cervical lymph node metastasis in patients with papillary thyroid carcinoma.

Evaluation of cardiac masses by real-time perfusion imaging echocardiography.

BACKGROUND: Diagnosis of cardiac masses is still challenging by echocardiography and distinguishing tumors from thrombi has important therapeutical implications. We sought to determine the diagnostic value of real-time perfusion echocardiography (RTPE) for cardiac masses characterization. METHODS: We prospectively studied 86 patients, 23 with malignant tumors (MT), 26 with benign tumors (BT), 33 with thrombi and 6 with pseudotumors who underwent RTPE. Mass perfusion was analyzed qualitatively and blood flow volume (A), blood flow velocity (ß), and microvascular blood flow (A x ß) were determined by quantitative RTPE. RESULTS: Logistic regression models showed that the probability of having a tumor increased by 15.8 times with a peripheral qualitative perfusion pattern, and 34.5 times with a central perfusion pattern, in comparison with the absence of perfusion. Using quantitative RTPE analysis, thrombi group had parameters of blood flow lower than tumor group. A values for thrombi, MT, and BT were 0.1 dB (0.01-0.22), 2.78 dB (1-7) and 2.58 dB (1.44-5), respectively; p < 0.05, while A x ß values were 0.0 dB/s(-1) (0.01-0.14), 2.00 dB/s(-1) (1-6), and 1.18 dB/s(-1) (0.52-3), respectively; p < 0.05. At peak dipyridamole stress, MT had greater microvascular blood volume than BT [A = 4.18 dB (2.14-7.93) versus A = 2.04 dB (1.09-3.55); p < 0.05], but no difference in blood flow [Axß = 2.46 dB/s(-1) (1.42-4.59) versus Axß = 1.55 dB/s [1] (0.51-4.08); p = NS]. An A value >3.28 dB at peak dipyridamole stress predicted MT (AUC = 0.75) and conferred 5.8-times higher chance of being MT rather than BT. CONCLUSION: RTPE demonstrated that cardiac tumors have greater microvascular blood volume and regional blood flow when compared with thrombi. Dipyridamole stress was useful in differentiating MT from BT.

Conventional and Doppler ultrasound for the differentiation of benign and malignant canine mammary tumours.

OBJECTIVES: The aim of this study was to evaluate the sensitivity of conventional and Doppler ultrasound for differentiation of benign and malignant mammary tumours in female dogs. METHODS: Mammary tumours were evaluated from 60 animals and divided into two distinct groups, group 1 (benign tumours) and group 2 (malignant tumours). The tumours were assessed by conventional ultrasound, Doppler ultrasound mode, histopathology and immunohistochemical detection of vascular endothelial growth factor. RESULTS: Conventional ultrasound examination was found to be ineffective in separating tumours into the two experimental groups. Similarly, using colour-flow Doppler ultrasound, no correlation was found between the presence of vascularisation and its characteristics between the two groups. Triplex Doppler ultrasound yielded average maximum velocities of 28·71 cm/s for malignant and 19·91 cm/s for benign tumours, which were significantly different (P=0·01). For vascular endothelial growth factor, an average score of 2·22 was found for group 2 and 1·66 for group 1 (P=0·03). Positive correlations were found between vascular endothelial growth factor and presence of vascularisation (P=0·04 and r=0·3658) and between vascular endothelial growth factor and maximum velocity (P=0·03 and r=0·3913). CLINICAL SIGNIFICANCE: Doppler evaluation may be used to predict malignancy of mammary tumours in bitches.

Radiotracers for different angiogenesis receptors in a melanoma model.

Early and reliable diagnosis of melanoma, a skin tumor with a poor prognosis, is extremely important. Phage display peptide libraries are a convenient screening resource for identifying bioactive peptides that interact with cancer targets. The aim of this study was to evaluate two technetium-99m tracers for angiogenesis detection in a melanoma model, using cyclic pegylated pentapeptide with RGD and NGR motifs conjugated with the bifunctional chelator mercaptoacetyltriglycine (MAG(3)). The conjugated peptides (10 µl of a µg/µl solution) were labeled with technetium-99m using a sodium tartrate buffer. Radiochemical evaluation was carried out by instant thin-layer chromatography and confirmed by high-performance liquid chromatography. The partition coefficient was determined and internalization assays were performed in two melanoma cell lines (B16F10 and SKMEL28). Biodistribution evaluation of the tracers was carried out in healthy animals at different time points and also in tumor-bearing mice, 120 min post injection. Blocking studies were also conducted by coinjection of cold peptides. The conjugates displayed a rather similar pharmacokinetic profile. They were radiolabeled with high radiochemical purity (>97%) and both were hydrophilic with preferential renal excretion. Yet, tumor uptake was higher for human than for murine melanoma cells, especially for [(99m)Tc]-MAG(3)-PEG(8)-c(RGDyk) (7.85±2.34%injected dose/g 120 min post injection). The performance of [(99m)Tc]-MAG(3)-PEG(8)-c(RGDyk) was better than the NGR tracer with regard to human melanoma uptake. In this sense, it should be considered for future radiotracer studies of tumor diagnosis.

A critical analysis of Doppler velocimetry in the differential diagnosis of malignant and benign ovarian masses.

OBJECTIVES: To evaluate the intratumoral reliability of color Doppler parameters and the contribution of Doppler sonography to the gray-scale differential diagnosis of ovarian masses. METHODS: An observational study was performed including 67 patients, 15 (22.4%) with malignant ovarian neoplasm and 52 (77.6%) with benign ovarian diseases. We performed the Doppler evaluation in two distinct vessels selected after decreasing the Doppler gain to sample only vessels with higher velocity flow. Doppler measurements were obtained from each identified vessel, and resistive index (RI), pulsatility index (PI), peak systolic velocity (PSV), and end-diastolic velocity (EDV) were measured. Intraclass coefficient of correlation (ICC), sensitivity, specificity, and potential improvement in gray-scale ultrasound performance were calculated. RESULTS: The general ICC were 0.60 (95% CI 0.42-0.73) for RI, 0.65 (95% CI 0.49-0.77) for PI, 0.07 (95% CI -0.17-0.30) for PSV, and 0.19 (95% CI -0.05-0.41) for EDV. The sensitivity and specificity were respectively 84.6% and 86.7% for RI, 69.2% and 93.3% for PI, 80.0% and 65.4% for gray-scale sonography, and 93.3% and 65.4% for gray-scale plus RI (p = 0.013). CONCLUSIONS: Gynecologists must be careful in interpreting results from Doppler evaluation of ovarian masses because PSV and EDV present poor intratumoral reliability. The lower RI value, evaluated in at least two distinct sites of the tumor, was able to improve the performance of gray-scale ultrasound in differential diagnosis of ovarian masses.

Nonfunctioning paraganglioma of the aortopulmonary window.

Aortopulmonary paraganglioma is a rare tumor of the mediastinum. The only effective treatment is complete resection, which may pose a surgical challenge because of its proximity to the heart, great vessels, and trachea, often rendering a complete resection difficult to achieve. We report a case in which the tumor was excised under cardiopulmonary bypass and resulted in massive bleeding only controlled by means of packing the pleural cavity during 48 hours, known as damage control strategy. The patient survived and has been disease-free for 2 years.

Hallazgos con ecografía Doppler color y tomografía computada helicoidal en tumores renales: relación entre volumen y grado de neovascularización / Renal tumors: correlation of volume with neovascularity by means of color Doppler, US and helical CT

Entre julio de 1997 y agosto de 1998, se analizaron en nuestro Servicio 23 neoplasias renales de distinta histología que fueron estudiadas mediante ecografía convencional, Doppler color, Power Doppler y tomografía computada helicoidal, obteniéndose en todos los casos confirmación antomopatológica. Basándonos en sus características volumétricas, los tumores se clasificaron en tres grupos. A la vez, se utilizó Doppler color como power Doppler para caracterizar el tipo e intensidad de neuvascularización tumoral, para obtener distintos registros espectorales, arteriales y venosos, y para calcular las diferentes velocidades de flujo con sus índices de resistencia. Se realizó TC helicoidal, antes y después de la inyección de contraste yodado endovenoso, con el objeto de establecer una correlación entre el volumen ecográfico y el obtenido por tomografía, así como observar los diferentes tipos de realce vascular tumoral y entablar una relación con los hallazgos obtenidos mediante Doppler color y Power Doppler. Los hallazgos deberán ampliarse a un mayor número de casos pero los resultados iniciales indican una importante correlación entre el volumen tumoral y el grado de vascularización en el examen Doppler color, especialmente en tumores de pequeño volumen, con un predominio del patrón hipovascular de los mismos. También se observó un aporte importante de este último en la caracterización de los tumores renales en relación con su histopatología (AU)