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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., (© 2021 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)

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  mm 2 /s; interquartile range [IQR]: 0.9 × 10 -3 ; 1.2 × 10 -3 ) as compared to patients with non IgG4-ROD (0.80 × 10 -3 mm 2 /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 mm 2 /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., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interest., (Copyright © 2021 Société française de radiologie. Published by Elsevier Masson SAS. All rights reserved.)

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.

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/mm 2 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  mm 2 /s [0.45] versus 1.04 × 10 -3  mm 2 /s [0.33], p < 0.001, and 0.75 × 10 -3  mm 2 /s [0.40] versus 0.98 × 10 -3  mm 2 /s [0.42], p < 0.001, respectively. D* was significantly higher in malignant lesions than in benign ones: 12.8 × 10 -3  mm 2 /s [20.17] versus 7.52 × 10 -3  mm 2 /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.

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., (© 2019 International Society for Magnetic Resonance in Medicine.)

To evaluate the relative contribution of different Magnetic Resonance Imaging (MRI) sequences for the extraction of radiomics features in a cohort of patients with lacrimal gland tumors. This prospective study was approved by the Institutional Review Board and signed informed consent was obtained from all participants. From December 2015 to April 2017, 37 patients with lacrimal gland lesions underwent MRI before surgery, including axial T1-WI, axial Diffusion-WI, coronal DIXON-T2-WI and coronal post-contrast DIXON-T1-WI. Two readers manually delineated both lacrimal glands to assess inter-observer reproducibility, and one reader performed two successive delineations to assess intra-observer reproducibility. Radiomics features were extracted using an in-house software to calculate 85 features per region-of-interest (510 features/patient). Reproducible features were defined as features presenting both an intra-class correlation coefficient ≥0.8 and a concordance correlation coefficient ≥0.9 across combinations of the three delineations. Among these features, the ones yielding redundant information were identified as clusters using hierarchical clustering based on the Spearman correlation coefficient. All the MR sequences provided reproducible radiomics features (range 14(16%)-37(44%)) and non-redundant clusters (range 5-14). The highest numbers of features and clusters were provided by the water and in-phase DIXON T2-WI and water and in-phase post-contrast DIXON T1-WI (37, 26, 26 and 26 features and 14,12, 9 and 11 clusters, respectively). A total of 145 reproducible features grouped into 51 independent clusters was provided by pooling all the MR sequences. All MRI sequences provided reproducible radiomics features yielding independent information which could potentially serve as biomarkers.

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/mm 2 ) 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.

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.]., (Copyright 2017, SLACK Incorporated.)

Objective: To assess the role of colour Doppler flow imaging (CDFI) in the diagnosis and management of lacrimal fossa lesions., Methods: Institutional ethical committee approval was obtained. Fifty-one patients with 62 lacrimal fossa lesions were retrospectively included from 2003-2015. All patients underwent conventional ultrasonography and CDFI, with a qualitative and quantitative analysis of the vascularization. All patients had lacrimal gland surgery. Definitive diagnosis was based on pathological examination., Results: The study included 47 non-epithelial lesions (NEL) and 15 epithelial lesions (EL), with 24 (39 %) malignant lesions and 38 (61 %) benign lesions. NEL were significantly more likely to present with septa (p < 0.001), hypoechogenicity (p < 0.001), high vascular intensity (p < 0.001), both central and peripheral vascularization (p < 0.001), tree-shape vascularization (p < 0.05) and a low resistance index (RI) (p < 0.0001). EL were significantly more likely to present with the presence of cysts (p < 0.001), and a higher RI. Receiver operating characteristic curves identified a RI value of 0.72 as the best cut-off to differentiate NEL from EL, with a sensitivity and specificity of 100 %., Conclusion: CDFI is a valuable tool in the differential diagnosis of lacrimal fossa lesions. Resistance index measurement enables substantial distinction between EL and NEL, thus providing crucial data for surgical management., Key Points: • CDFI is a valuable tool in lacrimal fossa lesions. • Resistance Index measurement enables substantial distinction between epithelial and non-epithelial lesions. • Management of patients becomes more appropriate.

Orbito-palpebral vascular pathology represents 10% of all the diseases of this area. The lesion may be discovered during a brain CT scan or MRI, or because it causes clinical symptoms such as orbital mass, visual or oculomotor alteration, pain, proptosis, or acute bleeding due to a complication of the lesion (hemorrhage, thrombosis). We present these lesions using an anatomical, clinical, imaging and therapeutic approach. We distinguish four different entities. Vascular tumors have common imaging characteristics (hypersignal on T2 sequence, contrast enhancement, abnormal vascularization well depicted with ultrasound and Doppler, and possible bleeding). The main lesions are cavernous hemangiomas, the most frequent lesion of that type during adulthood; infantile hemangiomas, the most frequent vascular tumor in children; and more seldomly, hemangioperitcytomas. True vascular malformations are divided according to their flow. Low flow lesions are venous (orbital varix), capillarovenous or lymphatic (lymphangioma). High flow malformations, more rare, are either arteriovenous or arterial malformations (aneurisms). Complex malformations include both low and high flow elements. Lesions leading to modifications of the orbito-palpebral blood flow are mainly due to cavernous sinus abnormalities, either direct carotid-cavernous fistula affecting young adults after severe head trauma, or dural fistula, more insidious, found in older adults. The last section is devoted to congenital syndromic vascular malformations (Sturge-Weber, Rendu-Olser…). This classification allows for a better understanding of these pathologies and their specific imaging features., (Copyright © 2016. Published by Elsevier Masson SAS.)

We report 11 patients who were referred to our institution for severe open-angle glaucoma who had a paraoptic cyst on MR imaging. All cysts were extraoptic and retrolaminar; most were deforming the adjacent optic nerve. Cysts had a high signal on T2 and FLAIR sequences, and a variable signal on T1 and variable echogenicity, suggesting different proteinaceous content. Arterial vascularization of the optic nerve was normal. Cyst volumes were inversely correlated with the severity of glaucoma on the same eye (P < .01-.05, Spearman correlation coefficient). We hypothesized that such cysts may reflect a valve mechanism, which would allow preservation of the translamina cribrosa pressure and thus could preserve visual function. The rarity of this association, together with the frequent mass effect of the cyst on the optic nerve, stresses the necessity of long-term follow-up in these patients., (© 2015 by American Journal of Neuroradiology.)

The term orbital tumor covers a wide range of benign and malignant diseases affecting specific component of the orbit or developing in contact with them. They are found incidentally or may be investigated as part of the assessment of a systemic disorder or because of orbital signs (exophthalmos, pain, etc.). Computed tomography, MRI and Color Doppler Ultrasound (CDU), play a varying role depending on the clinical presentation and the disease being investigated. This article reflects long experience in a reference center but does not claim to be exhaustive. We have chosen to consider these tumors from the perspective of their usual presentation, emphasizing the most common causes and suggestive radiological and clinical presentations (progressive or sudden-onset exophthalmos, children or adults, lacrimal gland lesions, periorbital lesions and enophthalmos). We will describe in particular muscle involvement (thyrotoxicosis and tumors), vascular lesions (cavernous sinus hemangioma, orbital varix, cystic lymphangioma), childhood lesions and orbital hematomas. We offer straightforward useful protocols for simple investigation and differential diagnosis. Readers who wish to go further to extend their knowledge in this fascinating area can refer to the references in the bibliography., (Copyright © 2014 Éditions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.)

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.

Purpose: To compare optical coherence tomography (OCT) and ultrasound biomicroscopy (UBM) for detection of plateau iris configuration and confirmation of plateau iris syndrome., Participants: Three subjects with plateau iris configuration were recruited. All patients underwent gonioscopy, UBM, and OCT., Methods: The anterior chamber angle in each patient was imaged with a commercially available OCT unit. The angle configurations were assessed and compared with the UBM images., Results: Both OCT and UBM showed excellent performance in identifying eyes with plateau iris. The UBM confirmed the plateau iris diagnosis by showing the iris root indentation caused by the ciliary body. The OCT, which is a rapid, non-contact exam, and non-operator-dependent, can only show indirect signs, because it cannot detect structures behind the iris. Nevertheless, the indirect signs with OCT were accurate enough to make the diagnosis. The OCT also shows the angle closure risk in a sitting patient, and is therefore more physiologic than the UBM exam, for which the patient is supine. OCT can directly show a patent laser iridotomy and confirm its efficacy. The OCT can detect indirect signs of plateau iris syndrome after iridotomy., Conclusion: The OCT unit can be practically employed to confirm a clinical suspicion of plateau iris configuration and syndrome., (Copyright 2010 Elsevier Masson SAS. All rights reserved.)

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.

Our goal is to help echographists and radiologists become familiar with the various possibilities indications, technique and results of ophtalmic ultrasonography. We used a multipurpose ultrasound unit. The frequency of the transducer has to be equal or superior to 7.5 MHz. Color Doppler allowing the study of low flows is useful. The study must be standardized: the first step is to obtain measurements of both eyes. Then the entire globe is systematically evaluated. Finally, the orbital structures and vessels of the eye and orbit are analized. After a review of the anatomy and the normal sonographic features, the main indications are described as well as the main pathologies. Special attention is paid to intravitreal hemorrhage, retinal and choroidal detachments, intraocular tumors and orbital space occupying lesions.

We report a case of a cavernous dural fistula in a 54-year-old man the source of inflammatory ocular symptoms. Poorly adapted treatment with corticosteroids led to iatrogenic complications. We will attempt to show the advantage of color Doppler imaging for the diagnosis of this infrequent lesion. The only indication of digitalized angiography is for endovascular treatment.

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., (Copyright 2003 Wiley Periodicals, Inc.)

Exophthalmos is the main symptom revealing orbital masses. This sign needs to be imaged mainly by MRI and/or CT. As Graves disease is the main etiology of exophthalmos, CT scan should be performed as the initial imaging modality. Indications for US and Doppler are mostly limited to the study of ocular masses, and eventually may help the characterization of extra-ocular lesions. In all cases, imaging is useful to characterize: the precise location of the lesion which can be the intra-conal space (including muscles), the extra-conal space (associated or not to an extra-orbital lesion), or the eyeball; the features of the lesion (density, signal, enhancement.). These findings are used to generate a differential diagnosis. Imaging is also useful to precise the extension of the mass, and in some cases to select the appropriate surgical approach, and for follow-up.

Purpose: To compare prospectively the reproducibility and accuracy of B-mode-guided biometry with those of A-scan biometry using a conventional A-mode probe to calculate intraocular lens (IOL) power., Setting: Department of Ophthalmology, Hôtel-Dieu de Paris, France., Methods: The axial length (AL) in 87 eyes of 72 candidates for cataract surgery was determined by B-mode-guided vector-A-mode and A-mode biometry using an Ophthascan S Ultrasound imager. Patients were assigned to one of two groups based on the B-mode biometry: nonmyopic (AL < 24.5 mm; n = 54) or myopic (AL > 24.5 mm; n = 33). Postoperative refractive results were compared with attempted values., Results: Mean AL variance was significantly greater when using the A-mode than the B-mode: 0.157 mm +/- 0.260 (SD) versus 0.015 +/- 0.018 mm in the myopic group (P < .001) and 0.024 +/- 0.024 +/- 0.045 versus 0.009 +/- 0.011 mm in the nonmyopic group (P < .001). More eyes having B-mode biometry achieved a final refraction within +/- 0.50 diopter (D) of the attempted refraction (63 and 43%, respectively; P < .05). No deviation greater than 1.60 D was observed with the B-mode in the myopic or nonmyopic group. Three cases with a such a deviation (up to 2.24 D) would have been observed had A-mode-based biometry been chosen for the IOL power calculation. In the myopic group, attempted postoperative refraction was within +/- 0.50 D in 78% of eyes having B-mode biometry compared with 65% having A-mode. This difference was not statistically significant. CONCLUSION> These results suggest that the reproducibility and accuracy of AL measurements are significantly better with B-mode-guided A-mode biometry than with A-mode biometry in myopic and nonmyopic eyes.

A man of 37 years of age developed portal hypertension which was observed on radiological examination as a mediastinal opacity having the appearance of a tumor. No oesophageal varices were seen on barium meal examination or by endoscopy. A smooth liver was seen during laparoscopy. Pre-operative hemodynamic studies showed that there was no sinus block. Thoracotomy revealed an aneurysm of the azygos veins. Exploratory laparotomy after coelio-mesenteric arteriography confirmed the diagnosis of diffuse nodular hyperplasia of the liver, cirrhosis, and portal hypertension. The findings in 16 cases of mediastinal opacity from portal hypertension reported in the published literature are discussed.