Search PubMed⌕ Search

Biomedical subjects

C Papavasiliou

Publications and source records attributed to C Papavasiliou.

At least 19 recordsLinked to original sources
PubMed1998

Radiation therapy alone for growth hormone-producing pituitary adenomas.

We present our experience in the treatment of growth hormone (GH)-producing pituitary adenomas using irradiation alone. Between 1983 and 1991, 21 patients suffering from GH-secreting pituitary adenomas were treated with radiotherapy alone. Two bilateral opposing coaxial fields were used in 10 patients and in the remaining 11 a third frontovertex field was added. Treatment was given in 1.8-2 Gy daily fractions and total dose ranged between 45 and 54 Gy. Treatment was given using a cobalt unit. Four patients treated with somatostatin prior to and 14 patients treated after the end of radiotherapy experienced symptom relief for 6-28 weeks. The 5-year actuarial rate of disease control was 72%. Five out of six failed patients had macroadenomas. Hypopituitarism was observed in 5/21 (24%) patients. Whereas RT alone is effective in the treatment of microadenomas, this is not true for large infiltrative macroadenomas.

Adult↗
PubMed1998

Megavoltage pituitary irradiation lowers but seldom leads to safe GH levels in acromegaly: a long-term follow-up study.

Radiotherapy (RT) has long been used in the treatment of acromegaly, but confusion regarding the definition of biochemical cure has hampered interpretation of previous reports on the outcome of this treatment. In the present study we present additional data using the currently accepted criteria of biochemical cure in a large group of patients followed up by our department. Forty-six acromegalic patients were treated with external beam megavoltage RT and followed up for a mean of 7.6 years (range 2-22 years). Only four patients had had previous surgical treatment by either transsphenoidal or transfrontal routes. Following RT, mean basal GH levels decreased from 30.9 ng/ml (5-96 ng/ml) to 11.5 ng/ml (1-36 ng/ml) at 10 years of follow up with a further fall to 6.1 ng/ml (1-29 ng/ml) in those patients followed up for more than 10 years. As a result, although mean GH levels of less than 5 ng/ml were achieved in 9/28 (30.1%) at 5 years, 6/19 (31.6%) at 10 years, and in 6/11 (54.5%) of those patients followed up for more than 10 years post-RT, only 0/28 (0%), 7/28 (25%), 4/19 (21%) and 1/11 (1%) achieved GH levels of <2.5 ng/ml at 2, 5. 10 and >10 years following RT. Thus, in the whole series only 10/48 (20.8%) patients showed a decrease of GH level to less than 2.5 ng/ml at their latest follow up. Hypopituitarism as a result of RT was only infrequently observed in this series; gonadal deficiency developed in 12 (26.6%) patients, thyrotrophin (TSH) deficiency in 3 (6.6%) and adrenocorticotrophin deficiency in 2 (4.4%). In conclusion, megavoltage RT is an effective treatment for the control of GH hypersecretion in acromegaly, with a continuing lowering effect for several years following RT but seldom leads to safe GH levels.

Acromegaly↗
PubMed1996

Pelvic floor reconstruction after major cancer surgery.

BACKGROUND: Many surgical techniques to keep the small intestine out of the pelvis after cancer surgery have been developed. METHODS: We used part of the ileum and its mesentery sutured around the linea terminalis in ten patients who underwent surgery for rectal or gynecologic carcinomas. RESULTS: All imaging studies of our patients on the tenth postoperative day confirmed the position of the bowel above the pelvis. Four of ten patients had radiation treatment postoperatively without any problems. CONCLUSION: Use of the ileum to reconstruct the pelvic floor seems to be a simple and efficacious technique to keep the pelvic area free. We believe this warrants further investigation in a larger number of patients.

Aged↗
PubMed1996

Combined teletherapy and intracavitary brachytherapy boost for the treatment of nasopharyngeal carcinoma.

For the non-metastatic nasopharyngeal carcinoma, external beam radiation therapy (median dose 64 Gy) and a boost of intracavitary irradiation (ICRT) has been given. Caesium-137 pellets of 40 mCi were used at a dose rate of 3-3.5 Gy/h, 1 cm from the sources. The median dose was 8.5 Gy. Overall 5-year actuarial survival for the 48 studied patients was 60.4% and LRFS was 64%. The procedure was well tolerated by our patients.

Brachytherapy↗
PubMed1996

Radiotherapy effects on vertebral bone marrow: easily recognizable changes in T2 relaxation times.

The effect of localized radiotherapy on vertebral bone marrow was demonstrated in two patients using quantitative MRI studies with pixel-by-pixel measurement of T2 relaxation times with generation of T2 images. Conventional T1-weighted spin-echo images were obtained as well. Irradiated vertebral bone marrow was found to have longer T2 relaxation times than the neighboring nonirradiated bone marrow. These changes corresponded to the increased signal intensity on T1-weighted images and to the field of radiotherapy and were noted 2.5 to 32 mo after radiotherapy. Radiologists should be aware of the increased T2 relaxation times in irradiated bone marrow to correctly assess spinal disorders in irradiated patients. The reported T2 changes may reflect the abundance of adipose cells that proliferate in bone marrow after radiotherapy, or may indicate an additional histological change, such as bone marrow necrosis or edema. Conclusive histological proof remains to be obtained.

Bone Marrow↗
PubMed1994

Clinical expressions of the expansion of the bone marrow in the chronic anemias: the role of radiotherapy.

PURPOSE: In the chronic anemias and particularly in the hemoglobinopathies and in the myeloproliferative disorders there is compensatory hypertrophy and expansion of the bone marrow. This results in severe rarefaction of the bone and in extramedullary hemopoiesis. METHODS AND MATERIALS: Morbid clinical expressions of the osseous changes are spontaneous fractures and osteoarthropathy, while extramedullary hemopoiesis presenting in the form of tumor-like masses may cause pressure symptoms on adjacent organs, particularly on the spinal cord. RESULTS AND CONCLUSION: Extramedullary hemopoiesis masses can be easily diagnosed since they present typical radiological appearance. Radiotherapy has been used for the treatment of these conditions.

Adolescent↗
PubMed1994

Correlation between spinal cord MRI and clinical features in patients with demyelinating disease.

Localisation of spinal cord lesions by MRI was correlated with neurological symptoms and signs in 16 patients with clinical and laboratory evidence of multiple sclerosis. There was good correspondence between spinal cord lesions and motor tract signs. On the other hand, superficial or deep sensory disturbances correlated with spinal cord lesions in only about a quarter of the patients. MRI of the spinal cord appeared to explain the myelopathy in 11 patients, while in 3 there was strong clinical evidence of more extensive demyelinating lesions. In 7 of the 16 patients MRI of the brain was normal.

Adolescent↗
PubMed1994

A feasibility study of partially accelerated radiotherapy for invasive bladder cancer.

Thirty-nine patients with histologically confirmed invasive bladder carcinoma (T2-3, N0, M0) were treated with a partially accelerated radiotherapy scheme. After 40 Gy/4 weeks of conventional fractionation we have accelerated the treatment in the last week giving two daily fractions of 2 Gy each, 4-6 h apart in the bladder only. Although the follow-up of some of the patients is not very long our results indicate that this relatively short radiotherapeutic scheme is feasible, convenient and probably safe for patients living in remote areas.

Aged↗
PubMed1994

A comparative study between Gd-DTPA and oral magnetic particles (OMP) as gastrointestinal (GI) contrast agents for MRI of the abdomen.

In the present study we compared two gastrointestinal contrast agents--Gd-DTPA, a positive signal, and oral magnetic particles (OMP), a negative signal contrast agent--in patients who were referred for MR imaging of the abdomen. Altogether 60 patients were examined with the former and 28 patients with the latter contrast before and after the administration of contrast media. Gd-DTPA was given either per os or per rectum. In comparing the results, it was shown that the diagnostic accuracy of postcontrast MRI in both groups was more or less similar to CT but much higher as compared with plain MRI. In the OMP series, first the contrast between the GI-filled lumen and the surrounding fat was much superior to that of the Gd-DTPA and, second, there was no evidence of any artifacts from bowel motion. However, the overall accuracy of the Gd-DTPA group was better compared with that of the OMP group. This was due to underfilling of the distal bowel because the OMP in those patients was administered only per os. Finally, Gd-DTPA had a more pleasant taste and fewer side effects. It is concluded that both contrast media are suitable for the upper abdomen because the results are comparable, whereas for the lower abdomen Gd-DTPA is superior because it can be used from both routes.

Abdomen↗
PubMed1994

Changes of serum transferrin and ceruloplasmin after radiation therapy in women with cervical or uterine carcinoma.

Serum transferrin and ceruloplasmin were measured in 27 healthy women as well as in 21 women who received fractionated radiation therapy (RT) after undergoing surgery for cervical or uterine carcinoma. Although no significant difference in the mean values of transferrin was found between the healthy women and the patients before the initiation of RT, a significantly lower concentration of transferrin after the end of RT (p < 0.001) was observed in comparison to that of controls and of patients before RT. On the contrary, a significantly higher serum concentration of ceruloplasmin was found in patients before and after RT compared to that in healthy women (p < 0.001). The observed increase of ceruloplasmin after RT was not found to be significantly different from the mean value before RT. In conclusion serum transferrin is reduced by RT, while ceruloplasmin which is higher in patients before RT shows a tendency for increase following RT.

Adult↗
PubMed1994

Oral magnetic particles as a contrast agent for MR imaging of the abdomen. A phase III clinical trial.

Twenty patients were investigated with MR imaging of the abdomen before and after the administration of oral magnetic particles in the form of a per os solution for opacification of the gastrointestinal lumen. The parameters which were evaluated were a) distribution of the contrast medium in the gastrointestinal tract, b) delineation with the contrast medium of the region of interest c) image quality of general contract effect of the contrast medium d) diagnostic accuracy compared with CT and plain MRI of the same region. At a concentration of 0.5 mg/oral magnetic particles produced a constant negative signal from the gastro- intestinal tract in all spin echo sequences (T1 weighted, T2 weighted, proton density). Its diagnostic accuracy was similar to CT but better than plain MR examination of the same region in 70% of the cases. The diagnostic accuracy was inferior in the lower abdomen because of underdistension of the bowel. Perhaps the solution to the problem would be the combined per os and per rectum administration of the contrast medium.

Abdomen↗
PubMed1993

Retrocrural masses of extramedullary hemopoiesis in beta-thalassemia.

A case of extramedullary hemopoiesis in an 18-yr-old girl suffering from beta-thalassemia is reported. Extramedullary hemopoietic masses were localized apart from the paraspinal region in the retrocrural areas as well as the presacral region associated with massive destruction of the sacrum. The importance of recognition of hemopoietic masses in these regions in conditions other than hereditary hemolytic anaemias is briefly discussed.

Adolescent↗
PubMed1993

Pathological fracture in haemoglobinopathy: treatment by irradiation.

A patient suffering from thalassaemia, with extreme osteoporosis, coarse trabeculation and cortical thinning of the bones, developed a pathological fracture of the left hip. This was treated by a single dose of radiotherapy. It is suggested that the radiotherapy facilitated the healing process by eliminating the causative factor of the fracture, which was the expanding and over-proliferating bone marrow.

Adult↗
PubMed1992

Magnetic resonance angiography compared to intra-arterial digital subtraction angiography in patients with subarachnoid haemorrhage.

In order to evaluate the sensitivity and specificity of magnetic resonance angiography (MRA) in spontaneous subarachnoid haemorrhage, 14 patients with recent haemorrhage verified by CT or lumbar puncture were investigated with both selective intra-arterial digital subtraction angiography (IA-DSA) and MRA by two independent teams, each having the same preangiographic information. The results were compared with each other and whenever possible (all positive cases except one) with those of surgical intervention. Seven patients were identified by MRA and IA-DSA as having a single aneurysm on the circle of Willis, 1 an aneurysm of the posterior inferior cerebellar artery 1 an aneurysm of the internal carotid artery (siphon) and 2 patients with two aneurysms on the circle of Willis. MRA and IA-DSA both failed to demonstrate aneurysms in 2 cases. Three patients had negative results on both methods and no surgical intervention was attempted. The aneurysms ranged from 0.3 to 1.5 cm in size. In most cases there was agreement between MRA and DSA, leading us to believe that, if the proper protocols are followed, MRA is a powerful alternative to other established methods in the detection of intracranial aneurysms. At this stage it will not replace IA-DSA prior to surgery, but the ability to obtain various projections using 3D MRA may improve surgical planning.

Adolescent↗