Extraocular muscle size comparison between normal and myopic eyes using standardized A scan echography.

The aim of this study was to establish the range of diameters of extraocular muscles in myopic patients and to obtain the baseline data to follow progression or regression of pathologies involving them. Standardized A scan and B scan ultrasound was used to measure the thickness of straight extraocular muscles at the muscle belly. No statistical differences were seen between right and left eyes. We found no consistent correlation with age or with axial length in the control or in the myopic patients (p>0.05). Diameters in myopic and control eyes were similar. This lack of difference between myopic and control muscle sizes means that we can obtain accurate measurements also from myopic patients.

Correlation of lens thickness with blood glucose control in diabetes mellitus.

The aim of this study was to verify if lens thickness in insulin-dependent diabetic patients is greater than in non-diabetics, and to establish which parameters affect the thickness of the lens age, diabetes duration, glycaemic control, insulin dose. Ultrasound biometry and blood glucose measurements were taken in 87 patients three times a day: fasting 2 and 4 h after lunch. The patient sample was divided into three groups: 30 with no retinopathy, 30 presented background retinopathy and 27 with proliferative retinopathy; 30 normal subjects with a similar age to the diabetic group, comprised the control group. No correlation was found between biometric values and blood glucose in the three groups (p < 0.05). A significant difference in lens thickness was found in the four groups, even after adjusting for age (p < 0.05). Significant differences in lens thickness were seen between proliferative retinopathy and the other groups, after adjusting for age and duration of diabetes (p < 0.05); lens thickness was shown to correlate with diabetes duration (p < 0.05).

[Ocular color Doppler echography: the examination technic, identification and flowmetry of the orbital vessels]. / Eco color Doppler oculare: tecnica d'esame, identificazione e flussimetria dei vasi orbitari.

We studied the main ocular and retrobulbar vessels with color-Doppler US and report on examination technique, detectability of the vessels and their flow characteristics to define the normal ranges of Doppler spectra for each artery and vein. We comparatively examined both eyes of 20 healthy subjects. Of each eye we studied the ophthalmic artery, the central retinal artery, the ciliary artery, the central retinal vein and the superior ophthalmic vein. The following flow parameters were considered: peak systolic velocity, end-diastolic velocity and resistive index for arteries; maximum and minimum velocity for veins. The examination lasted about 10 minutes per eye--20 minutes for each subject. In all subjects the five investigated vessels were identified in both eyes, and adequate Doppler spectra were obtained. The average peak systolic velocities of ophthalmic, central retinal and ciliary arteries were respectively about 35, 12 and 10 cm/s, with low resistance patterns (resistive index: 0.75, 0.72 and 0.68, respectively). The venous flow, which is usually continuous, may be sometimes influenced by cardiac and respiratory activities: the maximum velocities of superior ophthalmic and central retinal veins were about 6 and 5 cm/s, respectively. Color-Doppler US noninvasively visualizes both ocular and retrobulbar vessels, providing major hemodynamic information from different flow parameters; the knowledge of these parameters in normal conditions can be the basis of hemodynamic studies in many abnormal orbital conditions.

Correlation of corneal thickness with blood glucose control in diabetes mellitus.

The aim of this study was to prove the existence of a correlation between corneal thickness and glycaemic control in insulin-dependent patients. Ultrasound pachometry and blood glucose measurements were taken in 87 patients three times a day: fasting, two, and four hours after lunch. The sample was divided into three groups of patients: 30 of them did not have retinopathy, 30 presented background retinopathy and 27 proliferative retinopathy. Thirty normal age-matched subjects were the control group. No correlation was found between pachometry values, blood glucose and duration of diabetes in the three groups (p > 0.05). A significant increase in corneal thickness was found in patients with background and proliferative retinopathy compared to the others (p < 0.01). No corneal thickness differences resulted between background and proliferative retinopathy (p = 0.74).

Ocular involvement in acute lymphoblastic leukemia: an echographic study.

We report a case of acute lymphoblastic leukemia (ALL) with ocular involvement in which bilateral swelling of the optic disk head was noticed. Massive direct infiltration of the optic nerve head by leukemic cells can give rise to a clinical picture identical to that of a true papilledema. Ocular echography allowed a better and more complete interpretation of the optic disk involvement. No echographic description of a leukemic infiltration of the optic nerve head has been reported previously.

Capillary and cavernous hemangioma of the optic disc. Echographic and histological findings.

The ultrasonography features of optic disc hemangioma have been described in various reports but the extreme rarity of this ocular tumour makes any univocal interpretation of echographic findings difficult. The two cases of hemangioma of the optic disc described here, one of capillary hemangioma and the other of cavernous hemangioma, presented different echographic patterns. In the capillary hemangioma B-scan showed a mass lesion with smooth anterior border, acoustic solidity and no choroidal excavation. With A-scan there was an initial high spike with low/medium internal reflectivity. In the cavernous hemangioma, B-scan showed an elevated dome-shaped mass, with an anechoic area inside, and no choroidal excavation. With A-scan there was a high initial spike and irregular reflectivity. The eyes were enucleated for intractable neovascular glaucoma. Histological examination of the lesion explained the different echographic patterns. Ultrasonography is useful in the differential diagnosis of capillary and cavernous hemangioma.