Implantation iris cysts developing 24 years after penetrating keratoplasty.

PURPOSE: To report a case of iris implantation cysts occurring 24 years after penetrating keratoplasty and its management. OBSERVATIONS: A 60-year-old man was referred for diagnosis and management of white iris masses of the right eye. He had undergone bilateral penetrating keratoplasty 24 years before without complication. The clinical findings were suggestive of iris implantation cysts and Ultrasound Biomicroscopy (UBM) and anterior-segment optical coherence tomography confirmed the diagnosis. The patient did not develop any ocular complications from the cysts after one-year follow-up from the diagnosis of iris implantation cysts. CONCLUSIONS AND IMPORTANCE: Iris implantation cysts are rare benign tumors that develop after the ectopic implantation of epithelial cells within the iris stroma. They can be congenital or secondary to penetrating trauma or surgery. Their diagnosis relies on clinical examination and UBM. In case of intraocular complications, treatment may be required, otherwise observational follow-up is appropriate.

Diagnostic accuracy of Quantitative Colour Doppler Flow imaging in distinguishing Persistent Fetal Vasculature from Retinal Detachment.

PURPOSE: Distinguishing posterior persistent fetal vasculature (PFV) from retinal detachment (RD) may be very challenging clinically and ultrasonographically, as they share common morphological features. However, it is crucial, considering their substantially distinct management and treatment. We aimed to assess the relevance of quantitative colour Doppler flow imaging to distinguish PFV from RD in children. METHODS: This retrospective bi-centre study included 66 children (30 females and 36 males, mean age: 244 ± 257 days) with a clinically suspected diagnosis of RD or posterior PFV. All children underwent systematic and standardized conventional ultrasonography and colour Doppler flow imaging under general anaesthesia with a qualitative and quantitative analysis of the retrolental tissue's vascularization. Peak systolic velocity, end-diastolic velocity and resistive index were recorded for analysis. Whenever available, surgical findings were deemed gold standard for diagnosis. A Mann-Whitney U-test was used to compare quantitative colour Doppler flow imaging data. RESULTS: Peak systolic velocity and end-diastolic velocity were significantly lower in children with PFV versus RD: 2.7 (IQR: 0.5) versus 5.1 (IQR: 2.8), p < 0.001, and 0.0 (IQR: 0.0) versus 2.0 (IQR: 1.2), p < 0.001, respectively. Resistive index was significantly higher in children with PFV versus RD: 1 (IQR: 0) versus 0.6 (IQR: 0.1), p < 0.001. Area under curves (AUCs) were of 0.94, 0.99 and 1, respectively. No differences between PFV and RD were observed on structural ultrasound or qualitative analysis of colour Doppler. CONCLUSION: Quantitative colour Doppler flow imaging has an excellent accuracy in distinguishing PFV from RD in children. It may help to improve management and treatment.

Discriminating between IgG4-related orbital disease and other causes of orbital inflammation with intra voxel incoherent motion (IVIM) MR imaging at 3T.

PURPOSE: The purpose of this prospective study was to determine the capabilities of intravoxel incoherent motion (IVIM) MRI at 3 Tesla in discriminating between IgG4-related orbital disease (IgG4-ROD) and other causes of orbital inflammation. MATERIALS AND METHODS: Main selection criteria for the patients enrolled in this prospective study were age over 18 years and histopathologicaly proven orbital inflammatory lesion. MRI examinations were performed prior to surgery and treatment in all patients with suspected orbital inflammation. Two neuroradiologists, blinded to clinical data, independently analyzed structural MRI examinations and IVIM sequences obtained with 15 b values ranging from 0 to 2000 s/mm². Apparent diffusion coefficient (ADC), "true" diffusion coefficient (D), perfusion fraction (f) and pseudodiffusion coefficient (D*) values were calculated from all orbital lesions. Diagnostic capabilities of IVIM parameters were assessed using receiver operating-characteristic (ROC) curves and area under the curve (AUC). Sensitivity, specificity, and accuracy of IVIM parameters were calculated for the best threshold values and reported with their corresponding 95% confidence intervals (CI). RESULTS: Thirty-five patients (21 women and 14 men; mean age, 49.2 ± 13.75 [SD] years; age range: 23-77 years) with 48 orbital lesions were enrolled in the study. Fifteen patients (15/35; 43%) had IgG4-ROD and 20 (20/35; 57%) had other causes of orbital inflammation. Median D value was significantly greater in patients with IgG4-ROD (1 × 10-3 mm2/s; interquartile range [IQR]: 0.9 × 10-3; 1.2 × 10-3) as compared to patients with non IgG4-ROD (0.80 × 10-3 mm2/s; IQR: 0.7 × 10-3; 1 × 10-3) (P = 0.04). There was no significant difference for ADC, f or D*. Area under the curve were of 0.54, 0.73, 0.63 and 0.56 for ADC, D, f and D*, respectively. Optimal threshold derived from ROC curves for D was 0.87 × 10-3 mm2/s, yielding 92% sensitivity (95% CI: 62-100%) and 71% specificity (95% CI: 44-90%) for the diagnosis of IgG4-ROD. No differences in standard morphological MRI criteria were found between IgG4-ROD and non IgG4-ROD. CONCLUSION: Our study shows that IVIM MRI is a useful imaging technique to distinguish IgG4-ROD from other causes of orbital inflammation.

Dixon-T2WI magnetic resonance imaging at 3 tesla outperforms conventional imaging for thyroid eye disease.

OBJECTIVES: To determine the diagnostic performances of a single Dixon-T2-weighted imaging (WI) sequence compared to a conventional protocol including T1-, T2-, and fat-suppressed T2-weighted MRI at 3 T when assessing thyroid eye disease (TED). MATERIALS AND METHODS: This IRB-approved prospective single-center study enrolled participants presenting with confirmed TED from April 2015 to October 2019. They underwent an MRI, including a conventional protocol and a Dixon-T2WI sequence. Two neuroradiologists, blinded to all data, read both datasets independently and randomly. They assessed the presence of extraocular muscle (EOM) inflammation, enlargement, fatty degeneration, or fibrosis as well as the presence of artifacts. The Wilcoxon signed-rank test was used. RESULTS: Two hundred six participants were enrolled (135/206 [66%] women, 71/206 [34%] men, age 52.3 ± 13.2 years). Dixon-T2WI was significantly more likely to detect at least one inflamed EOM as compared to the conventional set (248/412 [60%] versus 228/412 [55%] eyes; (p = 0.02). Dixon-T2WI was more sensitive and specific than the conventional set for assessing muscular inflammation (100% versus 94.7% and 71.2% versus 68.5%, respectively). Dixon-T2WI was significantly less likely to show major or minor artifacts as compared to fat-suppressed T2WI (20/412 [5%] versus 109/412 [27%] eyes, p < 0.001, and 175/412 [42%] versus 257/412 [62%] eyes, p < 0.001). Confidence was significantly higher with Dixon-T2WI than with the conventional set (2.35 versus 2.24, p = 0.003). CONCLUSION: Dixon-T2WI showed higher sensitivity and specificity and showed fewer artifacts than a conventional protocol when assessing thyroid eye disease, in addition to higher self-reported confidence. KEY POINTS: • Dixon-T2WI has better sensitivity and specificity than a conventional protocol for assessing inflamed extraocular muscles in patients with thyroid eye disease. • Dixon-T2WI shows significantly fewer artifacts than fat-suppressed T2WI. • Dixon-T2WI is faster and is associated with significantly higher self-reported reader confidence as compared to a conventional protocol when assessing inflammatory extraocular muscles.

Intravoxel incoherent motion (IVIM) 3 T MRI for orbital lesion characterization.

OBJECTIVES: To determine the diagnostic accuracy of MRI intravoxel incoherent motion (IVIM) when characterizing orbital lesions, which is challenging due to a wide range of locations and histologic types. METHODS: This IRB-approved prospective single-center study enrolled participants presenting with an orbital lesion undergoing a 3-T MRI prior to surgery from December 2015 to July 2019. An IVIM sequence with 15 b values ranging from 0 to 2000 s/mm2 was performed. Two neuroradiologists, blinded to clinical data, individually analyzed morphological MRIs. They drew one region of interest inside each orbital lesion, providing apparent diffusion coefficient (ADC), true diffusion coefficient (D), perfusion fraction (f), and pseudodiffusion coefficient (D*) values. T test, Mann-Whitney U test, and receiver operating characteristic curve analyses were performed to discriminate between orbital lesions and to determine the diagnostic accuracy of the IVIM parameters. RESULTS: One hundred fifty-six participants (84 women and 72 men, mean age 54.4 ± 17.5 years) with 167 orbital lesions (98/167 [59%] benign lesions including 54 orbital inflammations and 69/167 [41%] malignant lesions including 32 lymphomas) were included in the study. ADC and D were significantly lower in malignant than in benign lesions: 0.8 × 10-3 mm2/s [0.45] versus 1.04 × 10-3 mm2/s [0.33], p < 0.001, and 0.75 × 10-3 mm2/s [0.40] versus 0.98 × 10-3 mm2/s [0.42], p < 0.001, respectively. D* was significantly higher in malignant lesions than in benign ones: 12.8 × 10-3 mm2/s [20.17] versus 7.52 × 10-3 mm2/s [7.57], p = 0.005. Area under curve was of 0.73, 0.74, 0.72, and 0.81 for ADC, D, D*, and a combination of D, f, and D*, respectively. CONCLUSIONS: Our study showed that IVIM might help better characterize orbital lesions. KEY POINTS: • Intravoxel incoherent motion (IVIM) helps clinicians to assess patients with orbital lesions. • Intravoxel incoherent motion (IVIM) helps clinicians to characterize orbital lymphoma versus orbital inflammation. • Management of patients becomes more appropriate.

Quality-based pharmacokinetic model selection on DCE-MRI for characterizing orbital lesions.

BACKGROUND: Although several studies have evaluated dynamic contrast-enhanced (DCE) MRI in the orbit, showing its utility when detecting and diagnosing orbital lesions, none have evaluated the pharmacokinetic models. PURPOSE: To provide a quality-based pharmacokinetic model selection for characterizing orbital lesions using DCE-MRI at 3.0T. STUDY TYPE: Prospective. POPULATION: From December 2015 to April 2017, 151 patients with an orbital lesion underwent MRI prior to surgery, including a high temporal resolution DCE sequence, divided into one training and one test dataset with 100 and 51 patients, respectively. FIELD STRENGTH/SEQUENCE: 3T/DCE. ASSESSMENT: Six different pharmacokinetic models were tested. STATISTICAL TESTS: Univariate and multivariate analyses were performed using Wilcoxon-2-sample tests and a logistic regression to compare parameters between malignant and benign tumors for each pharmacokinetic model for the whole cohort. Receiver operating characteristic (ROC) curve analyses were performed on the training dataset to determine area under curve (AUC) and optimal cutoff values for each pharmacokinetic model, then validated on the test dataset to calculate sensitivity, specificity, and accuracy. RESULTS: Regardless of the model, tissue blood flow and tissue blood volume values were significantly higher in malignant vs. benign lesions: 103.8-195.1 vs. 65-113.8, P [<10-4 -2.10-4 ] and 21.3-36.9 vs. 15.6-33.6, P [<10-4 -0.03] respectively. Extracellular volume fraction and permeability-surface area product or transfer constant appeared to be less relevant: 17.3-27.5 vs. 22.8-28.2, P [0.01-0.7], 1.7-4.9, P [0.2-0.9] and 9.5-38.8 vs. 8.1-22.8, P [<10-4 -0.6], respectively. ROC curves showed no significant differences in AUC between the different models. The two-compartment exchange (2CX) model ranked first for quality. DATA CONCLUSION: DCE MRI pharmacokinetic model-derived parameters appeared to be useful for discriminating benign from malignant orbital lesions. The 2CX model provided the best quality of modeling and should be recommended. Perfusion-related DCE parameters appeared to be significantly more relevant to the diagnostic process. Level of Evidence 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:1514-1525.

Iris melanoma relapsing sixteen years after proton-beam therapy: The importance of lifelong follow-up.

PURPOSE: To report a case of locally recurrent spindle-cell iris amelanotic melanoma 16 years after proton-beam therapy. OBSERVATIONS: In 2001, a 45-year-old man presented with an amelanotic iris melanoma, extending from the 5 to 10 o'clock positions on his left eye. High-frequency ultrasonography showed extension of melanoma into the ciliary body. He was initially managed with proton-beam therapy (60 Gy delivered in four fractions over four consecutive days) and underwent ocular and systemic examination at regular intervals over the following years. Local tumor control was achieved, and the patient did not develop metastasis during sixteen consecutive years. In 2017, 16 years after he received proton-beam therapy, the patient developed a focal amelanotic lesion strongly suggestive of a local recurrence of iris melanoma, although it extended from the 1 to 6 o'clock positions. He also presented with treatment-resistant glaucoma with an intraocular pressure (IOP) of 37 mmHg, despite maximal topical IOP-lowering therapy. Since a second irradiation of the anterior segment was contraindicated, the eye was enucleated. Pathological analysis confirmed the diagnosis of iris melanoma and demonstrated iridocorneal angle invasion extending from the initial site to the recurrent tumor location. CONCLUSIONS AND IMPORTANCE: Regular ophthalmological surveillance for life with gonioscopy and high-frequency ultrasonography is recommended in patients with iris melanoma, due to the possibility of delayed local recurrence more than a decade after the initial treatment.

Small Choroidal Melanoma Revealed by a Large Extrascleral Extension.

AIMS: Orbital extraocular extension of choroidal melanoma is very rare with small melanomas. We report the case of a patient whose small choroidal melanoma was initially overlooked and was revealed by a large extrascleral extension. METHODS: A 48-year-old Caucasian woman presented with sudden total visual loss in the right eye. Multicolor imaging of the fundus showed right optic disc edema and an orange and green lesion near the optic disc. The diagnosis of unilateral optic neuritis was made. Magnetic resonance imaging showed an extraocular mass adjacent to the optic nerve; on ultrasound, this mass was acoustically hollow and a small intraocular component was visible. RESULTS: Choroidal melanoma with a large extrascleral extension was diagnosed (T4eN0M0, stage IIIC according to the AJCC 7th TNM classification, 2010). The size of the extraocular nodule was 13 × 5 mm. Treatment consisted of enucleation followed by adjuvant external beam orbital radiotherapy. Tumor analysis showed a mixed cell type melanoma with monosomy 3. The patient developed liver metastasis 10 months after local treatment. CONCLUSION: Extraocular extension of choroidal melanoma can occur with small lesions. Prognosis is generally poor according to AJCC TNM. This case is a reminder that fundus examination may reveal the nature of the mass in some patients with orbital tumors.

Repeatability of apparent diffusion coefficient and intravoxel incoherent motion parameters at 3.0 Tesla in orbital lesions.

OBJECTIVES: To evaluate repeatability of intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) parameters in the orbit. METHODS: From December 2015 to March 2016, 22 patients were scanned twice using an IVIM sequence with 15b values (0-2,000 s/mm2) at 3.0T. Two readers independently delineated regions of interest in an orbital mass and in different intra-orbital and extra-orbital structures. Short-term test-retest repeatability and inter-observer agreement were assessed using the intra-class correlation coefficient (ICC), the coefficient of variation (CV) and Bland-Altman limits of agreements (BA-LA). RESULTS: Test-retest repeatability of IVIM parameters in the orbital mass was satisfactory for ADC and D (mean CV 12% and 14%, ICC 95% and 93%), poor for f and D*(means CV 43% and 110%, ICC 90% and 65%). Inter-observer repeatability agreement was almost perfect in the orbital mass for all the IVIM parameters (ICC = 95%, 93%, 94% and 90% for ADC, D, f and D*, respectively). CONCLUSIONS: IVIM appeared to be a robust tool to measure D in orbital lesions with good repeatability, but this approach showed a poor repeatability of f and D*. KEY POINTS: • IVIM technique is feasible in the orbit. • IVIM has a good-acceptable repeatability of D (CV range 12-25 %). • IVIM interobserver repeatability agreement is excellent (ICC range 90-95 %). • f or D* provide higher test-retest and interobserver variabilities.

Detection of an Iris Pigmented Epithelium Cyst in a Child by High Frequency Ultrasonography.

An 18-month-old boy presented with an iris pigmented epithelium cyst. The diagnosis was confirmed using high frequency ultrasonography. The cyst was determined to be in an intermediate location, thus needing no treatment provided that any potential complications were noted. However, continued monitoring is required to detect any changes to adapt management. [J Pediatr Ophthalmol Strabismus. 2017;54:e31-e33.].

Ectopia lentis associated with primary congenital glaucoma.

PURPOSE: To describe 3 cases of ectopia lentis (EL) associated with primary congenital glaucoma (PCG) and differentiate between primary and secondary EL regarding pathogenesis. METHODS: We reviewed the clinical charts of 3 children previously diagnosed with congenital glaucoma who developed secondary EL. The following points were noted: medical and surgical history, refraction, keratometry, corneal diameter, axial length (AL), intraocular pressure, and cup/disc ratio. RESULTS: The 3 patients were respectively aged 12, 3, and 4 months. A trabeculectomy was performed in both eyes at 1-week interval in all cases. The EL was noted during follow-up controls. Lensectomy/vitrectomy was performed in 2 patients, in case of high astigmatism (>5.00 D) and/or the lens border visible in the pupillary area. Postoperative refraction was hyperopic. CONCLUSIONS: Ectopia lentis secondary to PCG should be differentiated from primary EL regarding pathogenesis. Anterior segment distension appears to be the principal mechanism in these cases. Postoperative hyperopia is observed despite the increased AL secondary to PCG. These biometric results are due to global distension of the globe, which also flattens the cornea with consequently lower refractive effect.

[Discriminant analysis of patients with primary open-angle glaucoma by color Doppler exam and visual field]. / Análise discriminante dos pacientes portadores de glaucoma primário de ângulo aberto através do exame de Doppler colorido e do campo visual.

PURPOSE: To determine if variables from color Doppler and visual field exam could discriminate normal from glaucomatous eyes. METHODS: Prospectively, 36 patients with primary open-angle glaucoma (glaucoma group) and 20 normal volunteers (control group) were studied. Gender, age, central corneal thickness, intraocular pressure, Octopus automated perimetry global indices (mean defect and loss variance) and several parameters of the color Doppler (peak systolic velocity and resistivity index) were compared between groups. RESULTS: There was no statistically significant difference in age, central corneal thickness and intraocular pressure. Discriminant analysis showed that the variables: resistivity index (RI) in the short posterior ciliary artery (SPCA), mean defect (MD) and loss variance (LV) had presented significant influence for the positive diagnosis of glaucoma. The gotten discriminant function was: -3.637 + 0.109 x MD + 0.028 x LV + 4.325 x RI SPCA. Considering score -1.61, the probability of positive diagnosis of glaucoma was 90%. CONCLUSION: Through discriminant analysis it was possible to identify which of the color Doppler variables that associated to the visual field variables allowed differentiate normal from glaucomatous patients. These variables were: resistivity index in the short posterior ciliary artery, and the visual field variables, mean defect and loss variance.

Análise discriminante dos pacientes portadores de glaucoma primário de ângulo aberto através do exame de Doppler colorido e do campo visual / Discriminant analysis of patients with primary open-angle glaucoma by color Doppler exam and visual field

OBJETIVO: Determinar se as variáveis obtidas com exame Doppler colorido associadas às de campo visual são capazes de discriminar olhos normais de olhos glaucomatosos. MÉTODOS: Foram avaliados prospectivamente 36 pacientes portadores de glaucoma primário de ângulo aberto em uso de medicação antiglaucomatosa (grupo glaucoma) e 20 voluntários normais (grupo controle). Analisou-se a distribuição dos grupos quanto ao sexo, idade, espessura corneana central, pressão intraocular, índices globais da perimetria computadorizada Octopus ("mean defect" e "loss variance") e os parâmetros do Doppler colorido (velocidade sistólica máxima e índice de resistência). RESULTADOS: Não houve diferença estatística significativa entre os grupos em relação à idade, espessura corneana e pressão intraocular. A análise discriminante mostrou que as variáveis: índice de resistência (IR) da artéria ciliar curta posterior (ACCP), "mean defect" (MD) e "loss variance" (LV) apresentaram influência estatisticamente significativa para o diagnóstico positivo de glaucoma. A função discriminante obtida foi: -3,637 + 0,109 MD + 0,028 LV + 4,325 IR ACCP. A probabilidade do diagnóstico positivo do glaucoma a partir do "score" -1,61 foi de 90 por cento. CONCLUSÃO: Foi possível identificar através da análise discriminante, quais das variáveis do Doppler colorido que, associados às do campo visual, permitiram diferenciar pacientes glaucomatosos de normais. Essas variáveis foram: índice de resistência da artéria ciliar curta posterior e índices da perimetria computadorizada "mean defect" e "loss variance".

PURPOSE: To determine if variables from color Doppler and visual field exam could discriminate normal from glaucomatous eyes. METHODS: Prospectively, 36 patients with primary open-angle glaucoma (glaucoma group) and 20 normal volunteers (control group) were studied. Gender, age, central corneal thickness, intraocular pressure, Octopus automated perimetry global indices (mean defect and loss variance) and several parameters of the color Doppler (peak systolic velocity and resistivity index) were compared between groups. RESULTS: There was no statistically significant difference in age, central corneal thickness and intraocular pressure. Discriminant analysis showed that the variables: resistivity index (RI) in the short posterior ciliary artery (SPCA), mean defect (MD) and loss variance (LV) had presented significant influence for the positive diagnosis of glaucoma. The gotten discriminant function was: -3.637 + 0.109 x MD + 0.028 x LV + 4.325 x RI SPCA. Considering score -1.61, the probability of positive diagnosis of glaucoma was 90 percent. CONCLUSION: Through discriminant analysis it was possible to identify which of the color Doppler variables that associated to the visual field variables allowed differentiate normal from glaucomatous patients. These variables were: resistivity index in the short posterior ciliary artery, and the visual field variables, mean defect and loss variance.

Vitreoretinal dysplasia masquerading as Peters' anomaly.

PURPOSE: Vitreoretinal dysplasia is characterized by a congenital bilateral nonattachment of the retina. In some cases, anteroposition of the iris and lens can lead to corneolenticular contact and corneal opacity, masquerading as Peters' anomaly. We report 3 cases of vitreoretinal dysplasia initially diagnosed as Peters' anomaly. METHODS: Case report. RESULTS: Case 1: In a 3-year-old boy with bilateral corneal opacities, high frequency ultrasound showed iridolenticular adherences as in Peters' anomaly, but color Doppler imaging of the posterior pole revealed a bilateral total retinal detachment. Case 2: In an 18-month-old boy with bilateral corneal opacity and dense cataract, ultrasound revealed a shallow anterior chamber and bilateral vitreous hemorrhage with retinal detachment. Case 3: In a 6-month-old girl with bilateral central corneal opacity, shallow anterior chamber, iridocorneal synechiae, and a cataract, ultrasound revealed a total retinal detachment in the right eye, and was uncertain in the left eye. Corneal transplantation was attempted in the left eye, but a retinal detachment was discovered peroperatively. There were associated central nervous system anomalies. CONCLUSIONS: Vitreoretinal dysplasia is a potentially evolving disease and can lead to anterior chamber thinning, corneal opacity, and secondary glaucoma. Anterior and posterior segment ultrasound is essential to fix the correct diagnosis and prognosis.

Orbital cyst associated with ocular pit in an adult without microphthalmos.

We describe an adult without microphthalmos who developed an acquired compressive optic neuropathy secondary to an orbital cyst which showed direct communication with an optic disc pit. Such pits may be revealed by late complications such as orbital compressive cyst of the optic nerve, even in previously normal adult patients.

Orbital color Doppler imaging in embolic central retinal artery obliteration associated with neovascular glaucoma.

PURPOSE: To describe the detection of an embolism in the retrobulbar circulation using orbital color Doppler imaging (OCDI) in a patient with an inaccessible fundus because of neovascular glaucoma. METHODS: Review of the clinical, laboratory, photographic, and orbital color Doppler imaging records of a patient with central retinal artery occlusion (CRAO) associated with neovascular glaucoma. RESULTS: A 42-year-old man had no light perception in the left eye secondary to neovascular glaucoma. The fundus was not visible because of corneal edema. Orbital color Doppler imaging established the diagnosis of embolic CRAO as the cause of neovascular glaucoma. CONCLUSION: Orbital color Doppler imaging is an important diagnostic procedure for establishing CRAO as the cause of neovascular glaucoma when the fundus is not accessible. This noninvasive technology enables differentiation of embolic disease from other conditions as the cause of CRAO.

Quantitative echography in the follow-up of patients treated with proton-beam irradiation for primary choroidal melanomas.

Quantitative ultrasonic characterization yields information that is correlated to the tissue microstructure and increases the diagnostic potential of ultrasound. The measurement of acoustic properties of melanomas in vivo has not yet been reported after proton-beam irradiation. This prospective study was conducted on a cohort of 50 patients diagnosed with primary malignant melanoma to assess in vivo the ability of quantitative echography to detect changes in choroidal malignant melanomas after proton-beam irradiation and to follow the ultrasonographic changes during 24 months posttreatment. Echographic evaluations of these patients were performed at diagnosis and repeated every 6 months after treatment over a 2-y period. The acoustic parameters included in this work are derived from the calibrated tissue backscatter spectra (spectral slope, spectral intercept and apparent integrated backscatter) of a selected tumor volume after correction of the apparatus transfer function and beam diffraction. Clinical parameters resulting from conventional echography were also quantified and included mainly tumor height, tumor vascularity and internal reflectivity. Spectral intercept and apparent integrated backscatter were found to be the most useful to evaluate changes in melanomas after treatment. Significant (p < 0.05) differences of these parameter values were observed between pre- and postproton therapy. In particular, significant changes (compared with baseline) were observed for these parameters, even when the tumor size after treatment was not significantly different from baseline. The results suggest that quantitative spectrum analysis of frequency-dependent backscatter can provide information about the structural modifications of choroidal malignant melanomas as a result of proton-beam irradiation.

Color Doppler imaging of orbital vessels: personal experience and literature review.

Many Doppler imaging studies have been performed in recent years in a large number of ocular disorders because of improvements in the Doppler equipment used for detecting and measuring the low blood-flow velocities that are a requisite for the quantitative evaluation of blood flow in the orbital vessels. The ophthalmic artery, central retinal artery and vein, posterior ciliary arteries, and the superior ophthalmic vein can be easily identified using color Doppler sonography. The changes in local blood flow in these vessels assessed by spectral analysis pulsed Doppler sonography have been used to characterize and to obtain new insights into different nontumoral vascular disorders including carotid artery stenosis, central retinal vein occlusion, giant cell arteritis, glaucoma, diabetes, fistulas, and tumoral processes of the eye and orbit. Our experience has confirmed the important role of Doppler sonography in the assessment of subclinical changes in the vascular bed, in the understanding of different processes, for following up after specific treatments, and for determining the long-term prognosis of these various conditions.