PubMed Health⌕ Search

Biomedical subjects

S C Efremidis

Publications and source records attributed to S C Efremidis.

At least 19 recordsLinked to original sources
PubMed2006

Multi-detector row CT urography on a 16-row CT scanner in the evaluation of urothelial tumors.

The purpose of this study was to assess the role of multi-detector row CT urography (MDCTU), on a 16-row CT scanner in the evaluation of patients with painless hematuria, with emphasis placed in the detection of urothelial tumors. We retrospectively reviewed the MDCT urographies of 75 patients, referred for painless hematuria. The CT protocol included unenhanced images, obtained with a detector configuration of 16x1.5 mm and pitch of 1.2, nephrographic and excretory-phase images, obtained with a detector collimation of 16x0.75 mm and pitch of 1.2. Axial and coronal reformatted images were evaluated. Three-dimensional reformation of the excretory-phase images was performed using the volume-rendering technique. The standard of reference included clinical and imaging follow-up, cystoscopic, surgical and histologic findings. In 55 (73%) of 75 patients, the cause of hematuria was identified on MDCTU; the most common cause was urothelial cancer, including seven tumors with a diameter equal or smaller than 0.5 cm in diameter. Sixteen-row MDCTU provided satisfactory results in the investigation of patients with painless hematuria. The main advantage of the technique is its ability to detect uroepithelial malignancies.

Adult↗
PubMed2005

Solitary fibrous tumour of the epididymis: MRI features.

We present a case of a solitary fibrous tumour, located at the epididymis, in a 65-year-old man, presented with a scrotal mass. Ultrasound and MRI of the scrotum revealed a paratesticular mass, with rich vascularity, arising in the left epididymis. Radiological findings were non-specific and the patient underwent surgery.

Aged↗
PubMed2004

The height of the pituitary in preterm infants during the first 2 years of life: an MRI study.

Pituitary secretory activity is different in premature and full-term infants. The height of the pituitary is a marker of its secretory activity. Our purpose was to use MRI to measure height of the pituitary of premature infants and to compare it with full-term controls. The height was measured on a midline sagittal T1-weighted image in 86 premature infants (gestational age 26-36.9 weeks, mean 32.3+/-2.85 weeks, corrected age 0.33-2 years, mean 0.76+/-0.42 years) and in 70 age- and sex-matched full-term controls. The children were was divided into four age groups: A: > or =0.5 years; B: 0.51-1.0 year; C: 1.01-1.5 years; and D: 1.51-2.00 years. The gland was significantly (P<0.01) higher in the preterm infants than in the controls (3.88+/-0.61 vs 3.31+/-0.64 mm). In the preterm group no significant difference was found between children small or appropriate for gestational age or between those with and without periventricular leukomalacia. Pituitary height by age group was: A: 3.71+/-0.57, B: 3.81+/-0.56, C: 4.09+/-0.68; and D:4.45+/-0.57 mm; statistically significant (P<0.01) differences were found between groups A and D and B and D. The pituitary is thus higher in premature than in full-term controls and shows a trend to increase after the first year of corrected-age life.

Case-Control Studies↗
PubMed2004

Computed tomographic virtual cystoscopy for the detection of urinary bladder neoplasms.

OBJECTIVE: To evaluate the role of computed tomographic virtual cystoscopy (CTVC) in the detection of bladder neoplasms and to compare CTVC at conventional and reduced milliAmperes-second (mAs) settings. METHODS: Twenty-four patients with known bladder neoplasms from previous conventional cystoscopy were examined with CTVC. The urinary bladder was insufflated with room air and helical CT data were obtained. Virtual images were created using volume rendering algorithms. In eight patients we used both regular (240) and reduced (70) mAs values. The lesions were recorded on transverse tomographic slices and virtual images and compared with conventional cystoscopy, operative and pathology results. RESULTS: All bladder lesions (30) seen on conventional cystoscopy were demonstrated with CTVC. Two lesions detected on imaging studies and subsequently found at operation were not seen on conventional cystoscopy. In a third case of a neobladder, conventional cystoscopy was impossible due to neoplastic involvement of the penis. In all cases the lesions were equally conspicuous with conventional and low mAs values. CONCLUSIONS: Computed tomographic virtual cystoscopy is a minimally invasive technique that can provide comprehensive information about urinary bladder tumors. Furthermore, low mAs studies are equally effective for the examination of such patients.

Aged↗
PubMed2004

Sinus histocytosis with massive lymphadenopathy (Rosai-Dorfman disease) in a patient with primary Sjogren's syndrome.

Sinus histocytosis with massive lymphadenopathy is a rare disease that has been described by Rosai and Dorfman. It is characterized by massive, cervical lymphadenopathy, with extranodal manifestations in about 40% of patients. It occurs as a distinct entity, never associated with other diseases, and in most cases the prognosis is good. Lymphadenopathy is also a frequent sign of patients with primary Sjogren's syndrome (SS), usually associated with disease activity or concurrent infection. However, excessive lymphadenopathy in SS patients is a sign of lymphoproliferative disorder development. In this report, we describe a patient with primary SS, and excessive lymphadenopathy and splenomegaly who developed Rosai-Dorfman disease, and we discuss the possible aetiopathophysiological mechanism linking these two entities.

Biopsy, Needle↗
PubMed2003

MRI measurements of the pons and cerebellum in children born preterm; associations with the severity of periventricular leukomalacia and perinatal risk factors.

Our purpose was to measure the size of the pons and cerebellum in preterm babies with periventricular leukomalacia (PVL), and to study their relationship with the severity of PVL and with perinatal risk factors. We examined 33 premature children, mean gestational age 31 weeks, range 26-36 weeks with PVL on MRI, and 27 full-term controls. On MRI at 0.4-5.5 years (mean 1.4 years) we measured the area of the corpus callosum and vermis, the anteroposterior diameter of the pons and the volume of the cerebellum. The area of the corpus callosum was used as a marker of white matter loss and PVL severity. All regional brain measurements except that of the vermis were significantly lower in patients than controls: corpus callosum (mm(2)): 239.6+/-92.5 vs 434.8+/-126.8, P <0.01; pons (mm): 14.8+/-3.0 vs 17.9+/-1.4, P <0.01]; cerebellum (cm(3)): 68.2+/-31.6 vs 100.6+/-28.3, P <0.01; vermis (mm(2)): 808.1+/-292.2 vs 942.2+/-246.2, NS. Significant reduction in the area of the vermis: 411.3+/-203.3 vs 935+/-252.6 mm(2); cerebellar volume: 16.3+/-12.5 vs 96.6+/-20.2 mm(3); and the diameter of the pons: 10.1+/-2.2 vs 17.5+/-1.3 mm ( P<0.01) were observed in seven children with gestational age < or =28 weeks, severe hypotension and large patent ductus arteriosus (PDA). There was a significant correlation between the duration of mechanical ventilation and the size of the vermis, pons and cerebellum (R=-0.65, -0.57 and -0.73, respectively, P <0.01).

Case-Control Studies↗
PubMed2002

Conventional MRI and magnetisation transfer imaging of tumour-like multiple sclerosis in a child.

Tumefactive multiple sclerosis is a rare entity in children. Differential diagnosis includes other mass lesions such as neoplasm and abscess. A case of tumefactive multiple sclerosis in a child is presented. The open-ring pattern of enhancement on conventional MRI and magnetisation transfer imaging was important for the initial diagnosis and the evaluation of the course of the disease.

Child↗
PubMed2002

The role of MRI in the evaluation of hip joint disease in clinical subtypes of juvenile idiopathic arthritis.

The purpose of this study was to evaluate the role of MRI in the assessment of hip joint involvement in clinical subtypes of juvenile idiopathic arthritis (JIA). 28 patients (mean age 12.5 years) with JIA (oligoarthritis 8, polyarthritis 13, systemic arthritis 7) were examined with T(2) weighted turbo spin echo and T(1) weighted spin echo (plain and contrast enhanced) sequences. The severity of joint involvement was evaluated using an MR grading score: grade 1=no contrast enhancement; grade 2=focal synovial contrast enhancement; grade 3=diffuse synovial contrast enhancement; grade 4=grade 3+diffuse synovial thickening; grade 5=grade 4+villonodular synovial thickening; and grade 6=grade 5+cartilage and subchondral bone erosions. MRI was abnormal in 57.1% of cases (25% of oligoarthritis, 53.8% of polyarthritis and 100% of systemic arthritis). Clinical examination was positive in 32.1% of cases and was associated with higher MR grades (mean 4.6, SD 1.34) compared with a negative clinical examination, which was associated with lower MR grades (mean 1.78, SD 1.13) (p<0.001). Patients with active disease (mean grade 3.9, SD 2) had higher MR grades than those with inactive disease (mean grade 2.1, SD 1.4) (p<0.01). The MR grades were different in the three clinical subtypes: oligoarticular (mean 1.5, SD 1.06); polyarticular (mean 2.38, SD 1.55); and systemic (mean 4.85, SD 1.21) (F:12.3, p<0.001), with a significant difference between systemic arthritis and oligoarthritis, and between systemic arthritis and polyarthritis (p<0.001). MRI of the hip might be considered for inclusion in the study protocol of patients with JIA since it reveals joint involvement at early stages and provides a detailed evaluation of the extent of joint disease.

Adolescent↗
PubMed2001

Magnetisation transfer imaging of the normal adenohypophysis: the effect of sex and age.

Magnetisation transfer (MT) techniques provide tissue contrast depending mainly on the concentration of macromolecules. Because many macromolecules are involved in the secretory activity of the pituitary gland, MT techniques might be useful in the study of pituitary gland disorders. Our purpose was to establish a quantitative database of the MT ratio (MTR) of the normal adenohypophysis and to see whether there are age- and sex-related differences. Using a three-dimensional gradient-echo sequence for MT we studied the adenohypophysis in 56 males and 61 females aged 7 months-77 years; postsaturation images were obtained using an on-resonance binomial prepulse. The images were normal in all but three patients, two with meningiomas, one with a schwannoma). Adenohypophyseal MTR increased in both sexes up to 19 years of age (r = 0.47 males, 0.39 females, P < 0.05). In men after 20 years and in women from 20-49 years MTR decreased (r = -0.68, P < 0.001, r = -0.46, P < 0.05, respectively). In women aged 50-59 years the MTR again increased slightly. The MTR in males was slightly higher at all ages except before 9 and after 50 years of age. These differences were not statistically significant except in the 40-49 year group (P < 0.05).

Adolescent↗
PubMed2001

Myxopapillary ependymoma of the conus medullaris with subarachnoid haemorrhage: MRI in two cases.

Subarachnoid haemorrhage due to cauda equina tumour is rare. We report two myxopapillary ependymomas of the conus terminalis, presenting with in this way. Rims of low signal were observed at their upper and lower borders, mainly on T2-weighted images. This finding has been described in ependymomas of the cervical region but not, to our knowledge, in myxopapillary ependymomas of the conus terminalis.

Adolescent↗
PubMed2001

Dysembryoplastic neuroepithelial tumour and cerebellar atrophy: case report.

Dysembryoplastic neuroepithelial tumours (DNET) are mainly benign cortical lesions. DNET in the caudate nucleus, thalamus, hypothalamus, pons and cerebellar hemispheres has also been reported. We describe a fronto-temporo-parietal DNET extending to the ipsilateral thalamus and internal capsule, associated with cerebellar lobe atrophy. Involvement of the internal capsule and complication of DNET with cerebellar atrophy have not been reported previously. We emphasise the importance of early diagnosis and treatment of this rare condition.

Atrophy↗
PubMed2001

Pituitary gland height evaluated by MR in patients with beta-thalassemia major: a marker of pituitary gland function.

In transfusion-dependent beta-thalassemia major, increased iron deposition in the pituitary gland has a cytotoxic effect leading mainly to hypogonadotropic hypogonadism. Our purpose was to assess in these patients the height of the pituitary gland and to evaluate whether it represents a marker of pituitary gland function. In 29 patients with beta-thalassemia major and 35 age- and gender-matched controls the pituitary gland height was evaluated in a midline sagittal scan using a spin echo T1 -weighted (500/20 TR/TE) sequence. In all patients, an extensive endocrine evaluation was performed, including measurements of spontaneous and stimulated levels of gonadotropins, thyroid hormones, growth hormone, insulin-like growth factor, and adrenal hormones. The pituitary gland height was lower in thalassemic patients with hypogonadotropic hypogonadism (n = 15) (mean 3.48; SD 0.46) than in the age- and gender-matched controls (mean 6.29; SD 0.77), (P < 0.001). No statistically significant difference was found between thalassemic patients without hormone dysfunction (n = 14) (mean 5.34; SD 1.52) and age- and gender-matched controls (mean 5.91; SD 1.06). We conclude that in thalassemic patients the pituitary gland height is an additional marker of pituitary gland function and might be useful in clinical management.

Adolescent↗
PubMed2001

T(2) relaxation rate of basal ganglia and cortex in patients with beta-thalassaemia major.

In thalassaemic patients, neurophysiological disturbances have been associated with high serum ferritin levels and desferrioxamine therapy. In the presence of a magnetic field, ferritin, the main iron storage protein, induces a preferential decrease of the T(2) relaxation time. The purpose of this study was to evaluate thalassaemic patients for brain iron deposition by assessing the T(2) relaxation rate (1/T(2)) of the grey matter. 41 thalassaemic patients (age range 8.5-44 years, mean 24 years) and 58 age- and sex-matched controls were included in the study. Current serum ferritin levels were obtained. The 1/T(2) values of the cortex (motor and temporal) (mean 0.0122 ms(-1), SD 0.0004), putamen (mean 0.0137 ms(-1), SD 0.0004) and caudate nucleus (mean 0.0132 ms(-1), SD 0.0003) were higher in patients compared with the controls (mean 0.0110 ms(-1), SD 0.0004; mean 0.0120 ms(-1), SD 0.0005; mean 0.0117 ms(-1), SD 0.0003, respectively) (p<0.001 for all parameters). No statistically significant differences were found in the globus pallidus. No correlation was found between 1/T(2) and serum ferritin. The higher values of 1/T(2) in the cortex, putamen and caudate nucleus of thalassaemic patients probably reflect a higher iron deposition. The lack of differences in 1/T(2) of the globus pallidus might suggest that even in thalassaemic patients iron cannot exceed a saturation level.

Adolescent↗
PubMed1999

Pathways of lymph node involvement in upper abdominal malignancies: evaluation with high-resolution CT.

The aim of this study was to enhance our understanding of the pathways of lymphatic spread of primary carcinomas in the upper abdomen by recognizing the development, configuration, and frequency of nodal enlargement in discrete anatomic regions. The study included 417 patients with histologically confirmed carcinomas (CC) of the stomach (n = 267), liver (n = 98), gallbladder (n = 25), and bile ducts (n = 27). All patients were studied by high-resolution CT and tumor extension to the lymph nodes of the subperitoneal space was clearly identified in 59 patients [33 with CC of the stomach, 8 with CC of the gallbladder, 3 with CC of the bile ducts, and 15 with hepatocellular carcinoma (HCC)]. In 47 of 59 patients this extension was confirmed by surgery or aspiration biopsy. Three discrete anatomic groups of lymph nodes were recognized producing a relatively distinct CT configuration when involved: (a) the hepatoduodenal seen in 49 patients; (b) the peripancreatic demonstrated in 33 patients; and (c) the aortocaval recognized in 16 patients. These groups of lymph nodes can be seen individually involved or in combination. Recognition of involvement of these nodes is important for correct diagnosis and staging of upper abdominal malignancies. The development of this involvement follows the natural flow of lymph via the lesser omentum to the retroperitoneal space.

Aged↗
PubMed1998

Hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma is one of the world's most common malignancies. The aims of the present paper are to review data on (1) epidemiology and screening programmes for the early detection of the tumour and (2) advances in the diagnostic imaging and management. METHODS: Relevant English language articles, published between January 1985 and December 1997, were reviewed. Articles were identified through Medline search, using the key words 'hepatocellular carcinoma'. Articles cited in the bibliographies of these articles were searched manually. RESULTS: Hepatocellular carcinoma has a heterogeneous geographical distribution. Although its risk factors have been identified, the efficacy of screening programmes remains uncertain. Imaging has improved substantially with the recent application of dual-phase helical computed tomography and magnetic resonance imaging employing specific contrast agents. The comparative efficacy of conservative therapy and surgical resection is uncertain, since well controlled trials are lacking. CONCLUSION: Hepatocellular carcinoma is commonly a problem of two diseases, the malignancy itself and cirrhosis. This renders treatment rarely curative, even when surgical resection can be applied in a technically successful sense. Liver transplantation could be a definitive treatment but this is plagued by limited donor resources.

Carcinoma, Hepatocellular↗