Asynchronous ripening behavior of cactus pear (Opuntia ficus-indica) cultivars with respect to physicochemical and physiological attributes.

Physicochemical and physiological ripening events in cactus pear (Opuntia ficus-indica) fruit of cultivars 'Ntopia' and 'Hercules' were profiled against skin coloration from mature-green (S1) to over-mature (S5). Fructose and glucose accumulation were linear in 'Ntopia' but peaked near S3 in 'Hercules' synchronously to the appearance of sucrose. Betalains increased steadily in 'Ntopia' (103.2mg/l) but peaked before full skin coloration in 'Hercules' (49.7mg/l); whereas phenolic content remained invariable and ascorbate content peaked near S5 in both 'Ntopia' (108.6µg/g) and 'Hercules' (163.1µg/g). Cell wall material diminished with maturity though textural changes with ripening appeared not related to pectin solubilization but to weakening of glycan bonding and loss of neutral sugars. Fruit firmness rather was correlated to seed weight (r=0.89) and seed-to-pulp ratio (r=0.73). Cultivar differences highlighted in the chronology of ripening events are critical for defining optimum harvest maturity and postharvest handling protocols for premium quality cactus pear fruit.

Orbital cavernous hemangiomas: ultrasound and magnetic resonance imaging evaluation.

Cavernous hemangioma is the most common intraorbital lesion in adults. The aim of our study was to evaluate the magnetic resonance imaging (MRI) and ultrasound (US) characteristics of cavernous hemangioma and their role in the differential diagnosis of orbital tumors. Eight patients with orbital cavernous hemangiomas, five women and three men with a mean age of 48 years were examined in a period of six years. All patients underwent MRI examination and four patients were also evaluated by US. In all cases MRI depicted a well-defined intraconal tumor. The lesions were homogeneous, isointense to muscle on T1-weighted sequence and hyperintense to muscle on T2-weighted sequence in six patients. In one patient the mass was isointense on T1WI with heterogeneous signal intensity on T2WI and in one patient the lesion had heterogeneous signal intensity on both T1- and T2-weighted sequences. After intravenous contrast medium administration, the tumors showed initial inhomogeneous enhancement with progressive accumulation of contrast material on delayed images in seven patients and initial homogeneous enhancement in one patient. On ultrasonography, the orbital masses appeared slightly hyperechoic, heterogeneous with small areas of slow blood flow. The analysis of imaging characteristics of a well-defined intraconal lesion in an adult patient with painless progressive proptosis can be highly suggestive of the diagnosis of cavernous hemangioma.

Magnetic resonance imaging and ultrasonographic evaluation of retinal detachment in orbital uveal melanomas.

We assess the role of ultrasonography (US) in the evaluation of retinal detachment in patients with uveal melanomas, in correlation with magnetic resonance imaging (MRI) findings. Twenty-six patients (13♂ and 13♀) with uveal melanomas underwent MRI and US examination. The signal intensity of the tumors and retinal detachments were depicted using MRI. The position of retinal detachment in correlation with the position of intraocular tumor was also evaluated performing ultrasound examination. MRI and US identified uveal melanoma in all 26 patients. In 11 of the 26 patients (42.3%) uveal melanoma was accompanied by retinal detachment. MRI demonstrated retinal detachment in nine patients. US disclosed retinal detachment in two more cases. US has an important role in the depiction of uveal melanomas and associated retinal detachment. It also appears to be more sensitive than MRI in detecting retinal detachment in patients with orbital uveal melanomas.

Spinal segmental dysgenesis: presentation of a rare spinal congenital abnormality.

Segmental spinal dysgenesis is a rare spinal congenital abnormality in which a segment of the spine and spinal cord fails to develop completely. This entity is often associated with other congenital anomalies such as multiple vertebral segmentation defects, congenital vertebral displacement, tethered cord, hydromyelia and syringohydromyelia.

Is total brain volume correlated to cognitive function and education in patients with Alzheimer disease?

This study aimed to correlate whole brain volume measurements with MRI in patients with Alzheimer disease and the same Mini Mental State Examination (MMSE) but different levels of education. We describe the procedure we used to create 3D models of the brain from MRI images in patients with Alzheimer disease and then took volumetric measurements of the whole brain parenchyma. After this procedure we correlated the total brain volume measurements in patients with six or fewer years of education with those who had at least 12 years of education. Twenty patients with Alzheimer disease were examined with MRI. All of them had an MMSE score between 21 and 24 and were classified as mild Alzheimer disease. Ten of the patients had at least six years of education and the remaining ten had more than 12 years of education. The examinations were done by using a Siemens Expert Plus system of 1T and the MR images were studied using an automatic algorithm. The MRI images were segmented into grey, white matter and CSF. We then measured the volume of each component and classified those in each patient in relation to years of education. The whole procedure was completed successfully in 20 patients. After the volumetric study of the total brain volume by calculating separately grey matter, white matter and CSF, we classified the patients and made the correlation between those with six or fewer years of education and those with twelve or more years of study. Correlating the whole brain volume measurements of patients with Alzheimer disease and the same MMSE but different levels of education showed that there is no significant difference between the total brain volume of the two groups of our study.

3D MR Models and Volumetric Measurements of the Brain in Patients with Alzheimer's Disease.

This study aimed to describe the procedure we use to create 3D models of the brain parenchyma from MRI images and calculate the volume of the whole brain and different compartments of the brain in patients with Alzheimer's disease. The utility of the 3D models and volumetric measurements of the whole brain parenchyma and different brain structures is discussed. Thirty-six patients with Alzheimer's disease were examined during the last six months with MRI. Fourteen of them were men and 22 were women. The patients were between 53 and 67 years old. MR images were studied using an automatic algorithm. The images from MRI were segmented and then three-dimensional models of brain were produced to calculate the brain volume and the volume of the white matter, gray matter and CSF separately. The whole procedure was completed successfully in 34 patients. The procedure was unsuccessful in two patients due to movement artifacts in MR images. It is relatively easy to create 3D models of MR images and to obtain volumetric studies. If this procedure is adjusted in patients with Alzheimer's disease, we can provide information more clearly and accurately than single images alone. The information obtained can be used in daily clinical practice such as pharmaceutical treatment planning and results or in basic clinical research.

Pneumosinus Dilatans Syndrome of the Sphenoid Sinus. A CT Evaluation.

This study discusses the CT findings of pneumosinus dilatans of the sphenoid sinus, highlighting the clinically important CT characteristics. The CT findings of 26 patients with overpneumatization of the sphenoid sinus are presented in correlation with the clinical findings. Twenty-two patients had overpneumatization beyond the boundaries of the body of the sphenoid bone with or without bone remodelling but only two patients reported headaches. Thinning of the bone structures was also present in three patients but only one patient reported headaches. Overpneumatization of the sphenoid sinus with thinning of bunywalls reduced the width of the superior orbital fissure in one patient resulting in a gradual decrease of visual acuity. CT is an accurate method for the evaluation of overpneumatization of the sphenoid sinus due to its high sensitivity in depicting evidence of bone erosion using a bone window as imaging settings.

MRI evaluation of diastematomyelia and associated abnormalities.

Fourteen children were studied with a 1Tesla scanner to assess the role of magnetic resonance (MR) imaging in the recognition and evaluation of diastematomyelia and associated abnormalities. With MRI divided spinal cord was well imaged in its entire craniocaudal extent. Fibrous bands or bony septum when it contained a marrow cavity, were also well depicted. Direct visualization of the spinal cord itself is probably the most rewarding feature of MR imaging compared with other more conventional techniques. MR imaging demonstrated associated syringohydromyelia, segmentation anomalies, scoliosis, low position of the conus medularis and intradural lipoma that they were not detected with other radiologic studies.

Falx Cerebri Ossification: CT and MRI Evaluation.

During the last three years, CT and MRI brain scans of 40 patients revealed falx cerebri partial ossification as an incidental finding. The patients had been admitted for brain CT and MRI for several reasons. In most cases, there was no problem in the differential diagnosis of falx cerebri ossification during interpretation of the cases. In a few cases, the lesion should be distinguished from calcified meningioma, small hematoma in the interhemispheric fissure and in one case there was also meningeal infiltration of breast cancer. In these cases both CT and MRI scans of the brain were evaluated and a definite diagnosis was made.