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L Mortelmans

Publications and source records attributed to L Mortelmans.

At least 55 records · Page 3Linked to original sources
PubMed2001

Tc-99m HMPAO white blood cell scintigraphy in the assessment of the extent and severity of an acute exacerbation of ulcerative colitis.

PURPOSE: Ulcerative colitis (UC) is a chronic inflammatory bowel disease with frequent exacerbations, including the risk for toxic megacolon and severe complications. In very active disease, colonoscopy should not be performed to assess the severity and the extent of the disease. The aim of the current study was to determine whether Tc-99m HMPAO-labeled white blood cell (WBC) scintigraphy can be used as an alternative to colonoscopy to determine the extent and the severity of the disease in critically ill patients. METHODS: Twenty consecutive patients (7 women, 13 men; age 38.1 +/- 13.1 years) who had a severe attack of UC underwent scintigraphy on the day of admission. Leukocytes were labeled with 200 MBq (5.35 mCi) Tc-99m HMPAO. Planar anterior and posterior imaging of the abdomen was performed 45 and 120 minutes after WBC reinjection. The tracer uptake in the different colon segments was scored visually compared with bone marrow uptake. A symptom score was made and C-reactive protein was measured as a serologic marker of inflammation. Rectosigmoidoscopy with biopsy was performed within 24 hours of scintigraphy. Scintigraphic, endoscopic, and histologic results were compared for disease activity. RESULTS: The mean symptom score was 12.7 (+/-0.7) on a scale of 21, and mean the C-reactive protein level was 6.8 (+/-1.2) mg/l. No significant difference was found between the scintigraphic score of the rectum and the endoscopic or the histologic score. The best correlation was found with the latter (r = 0.66, P < 0.01). Based on the results of scintigraphy, disease involved the left side of the colon up to the splenic flexure in 10 patients. The other patients had pancolitis. CONCLUSIONS: Disease severity can be determined adequately by planar WBC scintigraphy in patients with severe attacks of UC. Because the presence and severity of disease correlates well with endoscopic and histologic findings, WBC scintigraphy can assess disease extent without the need for colonoscopy. This decreases the number and severity of complications that can occur in already critically ill patients.

Acute Disease↗
PubMed2001

The utility of SPECT in determining the relationship between radiation dose and salivary gland dysfunction after radiotherapy.

Salivary gland scintigraphy (SGS) is used to depict salivary gland dysfunction after radiotherapy (RT). The aim of this study was to investigate the utility of SGS combined with single photon emission computed tomography (SPECT). Twenty-one patients with a carcinoma of head and neck underwent SGS before and 1 month after RT. After injection of 370 MBq 99Tcm-pertechnetate, a biplanar dynamic acquisition (12 x 1 min) was started, followed by a SPECT acquisition during 4 min. Carbachol was then injected and a second dynamic study (16 x 1 min) was performed, again followed by a SPECT acquisition. The salivary excretion fraction (SEF) was calculated both from the geometric mean planar image for each parotid and from the SPECT data for each transverse plane through the parotids. The RT-induced changes in the SEF (dSEF) were correlated with the mean radiation dose calculated using tomography-based dosimetry. The mean radiation dose to the parotids was 44 Gy (range 4.4-68.1 Gy). The mean range of the variation in radiation dose to the transverse slices within the parotids of a patient was 24 Gy (range 6.2-51.9 Gy). Considering all transverse planes through the parotids in all patients, a linear correlation was found between the dSEF calculated using SGS-SPECT and the radiation dose (r=0.45, P=0.0001). Thirteen patients had a variation in radiation dose within the parotids of more than 20 Gy. In nine of these a significant intra-individual correlation between radiation dose and the dSEF of the transverse parotid slices was found (r range 0.55-0.97; P value range 0.037-0.0001). In conclusion, SGS-SPECT can be used for monitoring radiation-induced parotid gland dysfunction. It offers the unique possibility for the assessment of intra-individual dose-dysfunction curves in patients with large variations in the radiation dose within the parotids.

Adult↗
PubMed2001

Parathyroid imaging: basic principles and KU Leuven experience: MIBI-dual phase versus MIBI/I-123.

OBJECTIVE: The aim of our study was to evaluate and compare retrospectively MIBI-dual phase and MIBI/I-123 subtraction scintigraphy for preoperative localisation of hyperfunctioning parathyroid glands. In our department we also attempted to improve the results of the latter method by altering the subtraction technique. SUBJECTS AND METHODOLOGY: Fifty-one patients with hyperparathyroidism underwent preoperative evaluation with radionuclide scanning for the localisation of abnormal parathyroid glands. MIBI-dual phase and MIBI/I-123 subtraction scintigraphy were carried out respectively in fourteen and thirty-seven patients. Anatomopathological findings were used as the gold standard. RESULTS: Topographic identification of the pathological parathyroid glands was correct in 28% for MIBI-dual phase, in 46% for MIBI/I-123 ('old' method) and in 67.5% for MIBI/I-123 ('new' method). Relying on a normal histology of the normal parathyroid glands, there's a specificity of respectively 82.7%, 99% and 96%. CONCLUSION: MIBI/I-123 subtraction scintigraphy is superior to MIBI-dual phase for the preoperative detection and localisation of hyperfunctioning parathyroid tissue, especially when using a gradual subtraction.

Adenoma↗
PubMed2001

Evaluation of treatment response in patients with lymphoma using [18F]FDG-PET: differences between non-Hodgkin's lymphoma and Hodgkin's disease.

Fluorine-18fluorodeoxyglucose positron emission tomography ([18F]FDG-PET) has become a very useful technique for the therapy monitoring of patients with lymphoma. It provides unique information about the metabolic behavior of the disease independent of morphological criteria. In recent years, [18F]FDG-PET has proven to be a technique with high sensitivity for the detection of residual tumor. Therefore, [18F]FDG-PET seems to be the ideal tool for the evaluation of treatment response. However, most recent published studies included both HD and NHL, although [18F]FDG-PET scan results in Hodgkin's disease (HD) has a different impact than in Non Hodgkin's Lymphoma (NHL). In this paper, we summarize our findings on the role of [18F]FDG-PET in the therapy evaluation of lymphoma patients in a large group of patients and highlight the differences between the interpretations of the results of HD and NHL patients. Finally, a strategy for the implementation of [18F]FDG-PET in the management of lymphoma patients is proposed.

Fluorine↗
PubMed2000

Utility of positron emission tomography for the staging of patients with potentially operable esophageal carcinoma.

PURPOSE: A prospective study of preoperative tumor-node-metastasis staging of patients with esophageal cancer (EC) was designed to compare the accuracy of 18-F-fluoro-deoxy-D-glucose (FDG) positron emission tomography (PET) with conventional noninvasive modalities. PATIENTS AND METHODS: Seventy-four patients with carcinomas of the esophagus (n = 43) or gastroesophageal junction (n = 31) were studied. All patients underwent attenuation-corrected FDG-PET imaging, a spiral computed tomography (CT) scan, and an endoscopic ultrasound (EUS). RESULTS: FDG-PET demonstrated increased activity in the primary tumor in 70 of 74 patients (sensitivity: 95%). False-negative PET images were found in four patients with T1 lesions. Thirty-four patients (46%) had stage IV disease. FDG-PET had a higher accuracy for diagnosing stage IV disease compared with the combination of CT and EUS (82% v 64%, respectively; P: =.004). FDG-PET had additional diagnostic value in 16 (22%) of 74 patients by upstaging 11 (15%) and downstaging five (7%) patients. Thirty-nine (53%) of the 74 patients underwent a 2- or 3-field lymphadenectomy in conjunction with primary curative esophagectomy. In these patients, tumoral involvement was found in 21 local and 35 regional or distant lymph nodes (LN). For local LN, the sensitivity of FDG-PET was lower than EUS (33% v 81%, respectively; P: =.027), but the specificity may have been higher (89% v 67%, respectively; P: = not significant [NS]). For the assessment of regional and distant LN involvement, compared with the combined use of CT and EUS, FDG-PET had a higher specificity (90% v 98%, respectively; P: =. 025) and a similar sensitivity (46% v 43%, respectively; P: = NS). CONCLUSION: PET significantly improves the detection of stage IV disease in EC compared with the conventional staging modalities. PET improves diagnostic specificity for LN staging.

Adenocarcinoma↗
PubMed2000

Scintigraphic evaluation in rabbits of nasal drug delivery systems based on carbopol 971p((R)) and carboxymethylcellulose.

The residence time of apomorphine mucoadhesive preparations incorporating 99mTc labeled colloidal albumin in rabbit nasal cavity was evaluated by gamma scintigraphy. This technique was used to compare the nasal clearance of preparations based either on Carbopol 971P((R)) or lactose (control), each with and without apomorphine, or carboxymethylcellulose with apomorphine. The planar 1-min images showed an excipient-dependent progressive migration of radioactivity with time from the nasal cavity to the stomach and intestine. Thirty minutes post insufflation, the percentages of the formulations cleared from the nasal cavity were 47% for lactose, 26% for lactose/apomorphine, 10% for Carbopol 971P((R)), and 3% for both Carbopol 971P((R))/apomorphine and carboxymethylcellulose/apomorphine. Three hours post insufflation, the percentages of the formulations cleared from the nasal cavity were 70% for lactose, 58% for lactose/apomorphine, 24% for Carbopol 971P((R)), 12% for Carbopol 971P((R))/apomorphine, and 27% for carboxymethylcellulose/apomorphine. Apomorphine inhibited nasal mucociliary clearance since migration of the radioactivity administered with apomorphine containing preparations was in all cases slower than that of the corresponding powder without apomorphine. The peak plasma concentration of apomorphine was attained while all the formulations were still within the nasal cavity. The use of mucoadhesive polymers such as Carbopol 971P((R)) or carboxymethylcellulose in nasal dosage forms increases their residence time within the nasal cavity and provides the opportunity for sustained nasal drug delivery.

Acrylic Resins↗
PubMed2000

Self-injection ictal SPECT during partial seizures.

The authors compared ictal SPECT injection performed by medical personnel with self-injection ictal SPECT in six patients with refractory temporal lobe epilepsy. Self-injection was safe and started faster. Self-injection subtraction ictal SPECT coregistered to MRI (SISCOM) was localizing in three patients who had a complex partial seizure, but only one of three patients who had a simple partial seizure, which may limit its usefulness in clinical practice. The localizing information of self-injection was better in three patients, and obviated the need for depth-EEG studies in one patient.

Adult↗
PubMed2000

The utility of positron emission tomography for the diagnosis and staging of recurrent esophageal cancer.

OBJECTIVE: To study the utility of whole-body positron emission tomography with (18)F-fluoro-deoxy-D -glucose (FDG-PET) for the evaluation of recurrence after curative resection of cancer of the esophagus or gastroesophageal junction. METHODS: Forty-one patients with a clinical or radiologic suspicion of recurrent disease underwent conventional diagnostic work-up, including a spiral computed tomographic scan, an endoscopic ultrasound, and a dedicated whole-body FDG-PET. PET lesions were classified as equivocal or suspicious recurrence. The conventional diagnostic work-up and PET findings were correlated with pathology or with radiologic and clinical follow-up. Equivocal lesions were classified as positive. RESULTS: Forty recurrences were found in 33 patients. The lesions were perianastomotic (n = 9), regional (n = 12), and at distant sites (n = 19). For the diagnosis of a perianastomotic recurrence, the sensitivity, specificity, and accuracy of FDG-PET were 100%, 57%, and 74%, versus 100%, 93%, and 96% for conventional diagnostic work-up, respectively (P = not significant). False-positive PET lesions were found in patients with a progressive anastomotic stenosis requiring repetitive endoscopic dilatation. For the diagnosis of regional and distant recurrences, the sensitivity, specificity, and accuracy of PET were 94%, 82%, and 87%, versus 81% (P = not significant), 82% (P = not significant), and 81% (P =.0771) for conventional diagnostic work-up. All false-positive PET lesions (n = 4) had been reported as equivocal. On a patient base, PET provided additional information in 11 of 41 (27%) patients. A major impact on diagnosis was found in 5 patients with equivocal or negative findings on complete diagnostic work-up in whom PET provided a true-positive diagnosis. In 5 other patients the diagnosis was staged upward from localized to extended recurrent disease, and in 1 patient with an equivocal complete diagnostic work-up, PET correctly excluded malignancy. CONCLUSION: FDG-PET allows a highly sensitive diagnosis and accurate whole-body staging of symptomatic recurrent esophageal cancer. Further studies in asymptomatic patients are needed to assess the potential benefit on survival.

Adenocarcinoma↗
PubMed2000

Histopathologic validation of lymph node staging with FDG-PET scan in cancer of the esophagus and gastroesophageal junction: A prospective study based on primary surgery with extensive lymphadenectomy.

OBJECTIVE: To assess the value of positron emission tomography with 18fluorodeoxyglucose (FDG-PET) for preoperative lymph node staging of patients with primary cancer of the esophagus and gastroesophageal junction. SUMMARY BACKGROUND DATA: FDG-PET appears to be a promising tool in the preoperative staging of cancer of the esophagus and gastroesophageal junction. Recent reports indicate a higher sensitivity and specificity for detection of stage IV disease and a higher specificity for diagnosis of lymph node involvement compared with the standard use of computed tomography and endoscopic ultrasound. METHODS: Forty-two patients entered the prospective study. All underwent attenuation-corrected FDG-PET imaging of the neck, thorax, and upper abdomen, a spiral computed tomography scan, and an endoscopic ultrasound. The gold standard consisted exclusively of the histology of sampled nodes obtained by extensive two-field or three-field lymphadenectomies (n = 39) or from guided biopsies of suspicious distant nodes indicated by imaging (n = 3). RESULTS: The FDG-PET scan had lower accuracy for the diagnosis of locoregional nodes (N1-2) than combined computed tomography and endoscopic ultrasound (48% vs. 69%) because of a significant lack of sensitivity (22% vs. 83%). The accuracy for distant nodal metastasis (M+Ly), however, was significantly higher for FDG-PET than the combined use of computed tomography and endoscopic ultrasound (86% vs. 62%). Sensitivity was not significantly different, but specificity was greater (90% vs. 69%). The FDG-PET scan correctly upstaged five patients (12%) from N1-2 stage to M+Ly stage. One patient was falsely downstaged by FDG-PET scanning. CONCLUSIONS: FDG-PET scanning improves the clinical staging of lymph node involvement based on the increased detection of distant nodal metastases and on the superior specificity compared with conventional imaging modalities.

Adult↗
PubMed2000

Positron emission tomography scan in the diagnosis and follow-up of aortitis of the thoracic aorta.

We report a case of a 62-year-old female patient with an inflammatory reaction of the thoracic aortic wall. The diagnosis was made by computed tomographic (CT) scan, magnetic resonance imaging (MRI) and positron emission tomographic scan with 18-fluorodeoxyglucose (FDG-PET). The patient was treated with corticosteroids. The inflammatory parameters as well as FDG-uptake on PET scan returned to normal. Due to its aspecific presentation, the diagnosis of aortitis is often hard to establish. With this case the possible role of FDG-PET scan as a valuable tool in the diagnosis and monitoring of this inflammatory aortic disorder was demonstrated.

Aorta, Thoracic↗
PubMed2000

Hunter syndrome.

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Bone Diseases↗