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D A Kelekis

Publications and source records attributed to D A Kelekis.

At least 19 recordsLinked to original sources
PubMed2006

Virtual bronchoscopy versus thin section computed tomography in evaluation of moderate and low grade stenoses: receiver operating characteristic curve analysis.

PURPOSE: To evaluate the impact of virtual bronchoscopy, under proper threshold settings, on observer level of confidence in the assessment of bronchial abnormalities producing stenoses < or = 75% compared to interpretation of thin section computed tomography (CT) images. MATERIAL AND METHODS: Sixty-five patients with fiberoptic bronchoscopy positive for tracheobronchial abnormalities were evaluated in a blinded observer study using a commercially available virtual endoscopy software package. The findings of virtual endoscopy were compared with those of fiberoptic bronchoscopy using receiver operating characteristic curves (ROCs) and other statistical tools. RESULTS: A total of 102 lesions were identified by fiberoptic bronchoscopy, with 44 of these producing bronchial stenoses < or = 75%. Concerning the latter lesions, for virtual bronchoscopy the areas under the ROCs were 0.93 and 0.96 for the two observers, respectively, while for thin section CT the corresponding values were 0.86 and 0.88; the differences observed were statistically significant. Contrary to thin section CT, virtual bronchoscopy did not show statistically significant differences from fiberoptic bronchoscopy regarding estimation of degree of stenosis. CONCLUSION: Virtual bronchoscopy under proper threshold settings has a statistically significant impact on observer performance where moderate and low-grade bronchial stenoses are concerned and gives an estimate of the degree of stenosis more precisely than thin section CT.

Adult↗
PubMed2006

Hysterography -- new techniques.

For many years hysterosalpingography has provided images of the lumen of the fallopian tubes and the uterine cavity that were not available by other diagnostic modalities. In our days the development of new imaging and endoscopic techniques has limited its indications. In this paper we will discuss the current use of hysterosalpingography and the new techniques that have been developed such as sonohysterography.

Fallopian Tubes↗
PubMed2005

Cerebral metastases of malignant melanoma: contemporary treatment modalities and survival outcome.

The aim of our study was to analyze prognostic factors, effect of treatment and survival outcome of a contemporary cohort of melanoma patients with cerebral metastases and eventually propose new recommendations regarding therapy. Sixty four patients with melanoma brain metastases were treated in our department within a 15-year period. We performed a retrospective analysis of their survival with respect to the type of treatment instituted. Four groups were formed according to treatment: Group A patients treated with surgery followed by radiotherapy; group B temozolomide as first-line treatment and radiotherapy after cerebral disease progression; group C radiotherapy alone; group D supportive care only. Patients* characteristics influenced the selection of treatment modality: Group A (7.8%) patients with a single brain metastasis (p=0.001) and controlled extra-cranial disease (p<0.0001), while Group D (21.8%) patients with ulcerated primary lesions (p=0.010) and uncontrolled extra-cranial disease (p<0.0001). Only group B (26.6%) and C (43.7%) patients with similar characteristics including more than one brain lesion. Median overall survival was 3 months. In univariate analysis, median survival for groups A, B, C and D was 12, 5, 3 and 2 months, respectively (p<0.0001). The survival difference between the surgery and non-surgery groups was statistically significant (p=0.0011). Patients treated with supportive care had the worse prognosis (p<0.0001). A survival benefit for patients receiving first-line treatment with temozolomide, as compared to those receiving radiotherapy alone was noted (p=0.0267). In multivariate survival analysis, the number of brain lesions (p=0.0138), the absence of uncontrolled extra-cranial disease (p=0.00221) and the type of treatment for the cerebral disease (p=0.0053) remained significant independent survival predictors. Patients' characteristics remain a critical factor for treatment selection. The number of brain metastases, the extent of disease and the type of treatment represent independent survival predictors. Melanoma patients with a single brain metastasis and controlled extra-cranial disease gain a survival benefit, if surgically treated. Including temozolomide in the first-line treatment of melanoma patients with brain metastases who would have been treated with radiotherapy alone, might present a promising future direction affecting the length of survival.

Aged↗
PubMed2004

Iliac artery angioplasty : technique and results.

Percutaneous angioplasty is widely used for the treatment of iliac artery occlusive disease. Access to the ipsi-lateral, or less commonly contralateral, common femoral artery is obtained under local anaesthesia; the lesion is crossed with a guidewire and dilated with an angioplasty balloon catheter. This technique yields excellent immediate results with very few complications. Stent placement is used in lesions not amenable to balloon angioplasty, in complications, and recurrences. Evidence suggests that balloon angioplasty is the procedure of choice for iliac artery occlusive lesions. Stent placement should be reserved for angioplasty failures. However, primary stent placement is indicated in total occlusions. Lesion morphology is an important determinant of immediate success and long-term patency. TASC lesions type A and B are best treated with angioplasty and stenting, while TASC lesions type C and D show better results with surgical treatment. The development of new stent designs may expand the indications of the percutaneous treatment.

Angioplasty, Balloon↗
PubMed2004

Threshold selection in virtual bronchoscopy: phantom study and clinical implications.

PURPOSE: To investigate the effect of the threshold selection on the apparent diameter of a virtual bronchus and the virtual wall morphology and to examine the parameters that can affect the selection of the appropriate threshold for virtual bronchoscopy with single slice computed tomography. MATERIAL AND METHODS: A bronchial phantom containing plastic tubes simulating the airways of the tracheobronchial tree was constructed. The diameters of the virtual images of these tubes were measured using various thresholds for two different materials surrounding the tubes: air and water. These measurements were correlated with the density in HU of the walls. Furthermore, data from 20 virtual bronchoscopies in patients were retrospectively analyzed in the same way. RESULTS: The diameter of a virtual bronchus is strongly affected by the selected threshold. The appropriate threshold for accurate diameter representation depends on the density of the bronchial wall. CONCLUSION: Our results suggest that in clinical practice a single threshold value cannot be used for imaging all segments of the tracheobronchial tree. While a value of -520 is appropriate for the trachea and lobar segments, values down to -720 could be needed on the level of segmental and subsegmental bronchi. At these levels, a threshold value about 65 HU more negative than the value where the artificial holes appear on the virtual bronchial walls could be used.

Bronchoscopes↗
PubMed2003

Endovascular repair of abdominal aortic aneurysm in renal transplantation.

Successful endovascular correction of a 12-cm abdominal aortic aneurysm (AAA) is described in a 76-year-old man with a functional pelvic renal transplant and 18-month follow-up. Endovascular treatment is a safe alternative to surgery for AAA correction in the elderly post-transplantation patient since it does not require flow interruption during the procedure.

Aged↗
PubMed2002

Chondrosarcoma of the larynx: treatment with radiotherapy.

The case of a 50-year-old man with chondrosarcoma of the larynx treated with radiotherapy is reported. The patient presented with hoarseness and dyspnea. He underwent computed tomography (CT), which demonstrated a soft tissue mass of the larynx. Direct laryngoscopy with biopsy established the diagnosis of chondrosarcoma. Although experience with radiotherapy in these cases has been lacking in the literature, it was considered and eventually used, as radical surgery would result in severe cosmetic and functional impairment. Radiation therapy alone resulted in long-term remission of the tumour for more than 3 years. The patient has been followed up using CT and direct laryngoscopy for early detection of recurrence or metastases.

Chondrosarcoma↗
PubMed2002

Malignant melanoma metastatic to the gastrointestinal tract.

A retrospective study of 385 melanoma patients was performed, with the goal of evaluating the clinical characteristics, the role of imaging and the impact of treatment on patients with gastrointestinal (GI) metastases. Eighteen patients (4.7%) had GI tract metastases. In 50% the primary lesion was on the lower extremities (P< 0.01), while 61.1% had nodular melanomas (P < 0.01). Imaging and/or endoscopy were undertaken in 72.2% of the patients, yielding positive results in all. Eight patients underwent curative surgery, two received no treatment, while the remaining eight patients had chemotherapy or immunochemotherapy. Long-term palliation was offered to 87.5% of the surgical patients compared with 50% of the patients treated medically. Median survival in the patients treated with surgery was 47.5 months compared with 5.8 months in the medical group (P < 0.01). GI tract metastases were more common in patients with nodular melanoma of the lower extremities. To our knowledge, this is the first study correlating the primary lesion's characteristics with the development of GI tract metastases. Imaging is effective in the diagnosis of GI tract involvement. Melanoma patients with GI tract metastases can benefit from palliation by surgical resection. Survival is improved when such patients are treated with curative surgery.

Adolescent↗
PubMed2002

Percutaneous CT-guided drainage of splenic abscess.

OBJECTIVE: The objective of our study was to determine the current role of percutaneous CT-guided drainage as an alternative to surgical treatment of splenic abscesses. CONCLUSION: Splenic abscess is an uncommon entity that can be treated percutaneously. CT-guided drainage of splenic abscess seems to be a safe and effective alternative to surgery, allowing preservation of the spleen.

Abscess↗
PubMed2001

Stereotactic biopsy of brain stem lesions.

The successful therapy of space-occupying lesions of the brain stem, depends on precise histological diagnosis. Although the clinical management and contemporary imaging techniques (computerized tomography and magnetic resonance imaging) are now able to reveal and approach the diagnosis in these cases, only the combination of these two with the use of contemporary stereotactic systems, is able to secure the precise histological diagnosis for the patient with a good degree of safety. This study presents the first five patients in Greece with space-occupying lesions of the brain stem, in whom a stereotactic biopsy was carried out. All patients were subjected to CT-guided stereotactic biopsy, via the frontal approach in 4 patients with lesions in the superior pons and the mesencephalon and in one patient via the transcerebellar approach, for a lesion in the lateral surface of the pons. Precise histological diagnosis was possible and on the basis of a reliable choice of histological criteria the appropriate therapeutic approach was chosen, thus avoiding the old "empirical" treatment.

Adult↗
PubMed2001

Malignant fibrous histiocytoma of the trunk metastatic to the liver: treatment with transcatheter intrahepatic chemoembolization.

We report a patient with symptomatic liver metastases as the sole site of recurrence of a previously resected malignant fibrous histiocytoma of the trunk. We treated the patient with two sessions of transcatheter chemoembolization. Tumor regression was achieved, and the patient remained free of symptoms 23 months after the diagnosis of liver involvement, when he died of acute myocardial infarction. To our knowledge, this is the only case of transcatheter chemoembolization of liver metastases from soft-tissue sarcoma reported in the literature. Although it is a single case, it shows that this method may be a promising therapy for this grave disease.

Carboplatin↗
PubMed1996

Giant cell arteritis presenting as pulseless disease of the upper extremities.

The most frequently recognized clinical features of giant cell arteritis (GCA) derive from the involvement of the cranial arteries. In 10% of patients, however, the aorta and its major branches, are also affected. We report a case of a 53-year-old woman presenting with a fainting episode and diminished pulses in the upper extremities. Histologic examination of the temporal artery revealed features of giant cell arteritis.

Angiography↗