Prognostic evaluation of PET/CT in residual post-chemotherapy masses in patients with diffuse large B-cell lymphoma and its impact on survival

Aim of the work: To evaluate the prognostic value and accuracy of PET/CT in DLBCL patients with post-treatment CT-residual masses with concern in overall (OAS) and progression-free survival (PFS). Materials and methods: We retrospectively studied 62 patients with DLBCL who had CT documented residual masses (CRu) after completion of chemotherapy. Results: Forty-four patients with negative PET scan were free of relapse while 4 out of 18 patients with positive scan showed CR, the other 14 patients had developed relapse. PET attained a sensitivity of 100%, a specificity of 91%, a NPV of 100% and a PPV of 77.8% and an accuracy of 93.5%. The median OAS time was 33.59 months in patients with negative scan and 19.00 months in patients with positive scan with highly significant correlation (P value 0.0001) and the median PFS time was 29.53 months in patients with negative scan versus only 4.00 months in patients with positive scan with highly significant correlation (P value 0.0000). Conclusion: PET/CT plays helpful part in evaluation of therapy response in DLBCL patients with CT residual mass and post-chemotherapy PET could be used as an accurate and good predictor of OAS and PFS

Assessment of acromial morphology in association with rotator cuff tear using magnetic resonance imaging

Purpose: To identify the morphological characteristics of the acromion associated with RCT using MRI. Also, to recognize which type of the acromion could be risk factor for full thickness RCT. Materials and methods: Fifty-six patients with RCT (either partial or full thickness tear) and 30 control volunteers were enrolled in this study. Their shoulders were imaged by MRI. The acromial shapes were classified into type I (flat), type II (curved), type III (hooked) and type IV (convex). Additional measurements including acromial thickness, acromio-humeral distance (AHD), acromial index (AI) and lateral acromial angle (LAA) were performed for further assessment. Results: Type-II was the most commonly encountered acromial shape in both patients with RCT (44.6%) and control group (43.3%) with no significant difference in the incidence of each acromial shape between the two groups (P > 0.05). The acromial thickness, AHD, AI and LAA were significantly different in patients with RCT compared to control group (P < 0.001). Full thickness tear was significantly associated with type-III (P < 0.05). Conclusion: Type-III acromion (hooked shaped) could be a risk factor for full thickness RCT

The diagnostic value of PET/CT in recurrence and distant metastasis in breast cancer patients and impact on disease free survival

Aim of work: To detect the diagnostic value of PET/CT in breast cancer patients. We compared the performance of PET/CT with that of conventional imaging in detection of recurrence and distant metastasis and evaluated the impact PET/CT results have on disease free survival. Materials and methods: We retrospectively studied 50 patients with breast cancer with clinical suspicion of recurrent or metastatic lesion and who underwent PET/CT and conventional imaging procedures. The imaging results were retrospectively compared with histopathology and clinical follow-up as a reference standard. Results: PET/CT detected distant metastases with a sensitivity of 97% and a specificity of 93%. In contrast, the sensitivity and specificity of combined conventional imaging procedures were 75% and 73%, respectively, disease-free survival was significantly shorter in the 34 M1-PET/CT patients than in the 14 M0-PET/CT patients (log-rank P = 0.002) also PET/CT detected recurrence in 1 patient with equivocal mammographic findings. Conclusion: In breast cancer, PET/CT is superior to conventional imaging procedures for detection of recurrence, distant metastases and PET/CT can be used to improve prediction of the clinical outcome of breast cancer patients

Role of magnetic resonance imaging in pre-operative assessment of ano-rectal fistula

Aim of the work: To evaluate the role of magnetic resonance imaging (MRI) in preoperative assessment of ano-rectal fistula and tracing its full extent and relationship. Materials and methods: Twenty-four patients with ano-rectal fistula were enrolled in this study. They were examined with different MRI sequences for evaluation of the fistulas and their extent. Fistulas were classified according to St. James’s University Hospital MRI based classification system (which correlates the Parks surgical classification to anatomic MRI findings) into 5 grades. Then, interrelation between surgical and MRI findings was statistically analyzed with evaluation of the accuracy of each MRI sequence used. Results: Grade 1 was the most frequent (37.5%) type of ano-rectal fistula. The most common location of the internal opening of the fistula was at 6 o’clock position. Combination of oblique coronal and axial planes of contrast-enhanced fat suppressed T1-weighed fast spin-echo (CE FS T1WFSE) sequence images showed the highest accuracy (99.4%) in diagnosis of ano-rectal fistula. Conclusion: MRI is a useful imaging tool in the preoperative assessment of ano-rectal fistula. A significant accordance between surgical and MRI findings was achieved by using combination of coronal and axial planes of CE FS T1WFSE sequence images

In vivo neurobiochemical changes of the posterior cingulate gyrus in patients with Alzheimer’s disease detected by multivoxel proton magnetic resonance spectroscopy

Aim of the work: To study the neurobiochemical changes in patients with Alzheimer’s disease (AD) by multivoxel 1H-MRS. Materials and methods: Twenty-five patients with probable AD and 12 age- and sex-matched normal controls were subjected to assessment of cognitive functions by the Mini Mental State Examination (MMSE) and imaging with multivoxel 1H-MRS for measuring the NAA/Cho, NAA/Cr, Cho/Cr, MI/NAA and MI/Cr ratios in the posterior cingulate gyrus (PCG) bilaterally. Results: Patients with AD showed significant decrease in NAA/Cho and NAA/Cr, significant increase in MI/NAA and MI/Cr and non-significant increase in Cho/Cr ratios compared to control. Also, the severity of cognitive impairment was significantly associated with these changes. The NAA/Cho ratio at a cut-off value ⩽1.14 showed accuracy (94%), the NAA/Cr ratio at a cut-off value ⩽1.40 showed accuracy (97%), the Cho/Cr ratio at a cut-off value >1.29 showed accuracy (85%), the MI/NAA ratio at a cut-off value >0.60 showed accuracy (98%), and the MI/Cr ratio at a cut-off value >0.83 showed accuracy (97%). Conclusion: The multi-voxels 1H-MRS of the PCG is sensitive to biochemical changes in AD. The 1H-MRS peak metabolite concentration ratios may be useful as markers for the progression of AD

Exudative

Background: Pleural tissue can be harvested either by means of closed biopsies, thoracoscopy or open surgical biopsies. Access to thoracoscopy and open surgical biopsies is limited in many parts of the world and closed biopsies are therefore the preferred initial investigation (Diacon et al., 2003) [6]. Aim of the study: This study aimed to compare the diagnostic efficiency of image-assisted ANPB with that of medical thoracoscopy in patients with exudative pleural effusion. Patients and methods: Forty patients with non-diagnosed exudative pleural effusions were recruited. All had a contrast-enhanced thoracic CT scan to assess pleural thickening. Patients were randomly stratified by baseline pleural thickening, to either image-assisted Abrams’ pleural biopsy (n = 20) or medical thoracoscopy biopsy (n = 20). Results: Diagnostic sensitivity of image-assisted ANPB for 20 patients (group I) was 75% (15/20), for group Ia was 60% (6/10), and for group Ib was 90% (9/10). Diagnostic sensitivity of thoracoscopy for 20 patients (group II) was 85% (17/20), for group IIa was 80% (8/10), and for group IIb was 90% (9/10). Conclusions: Image-assisted Abram-needle pleural biopsy is a primary alternative to thoracoscopy in exudative pleural effusions associated with pleural thickening

Role of diffusion weighted imaging and proton magnetic resonance spectroscopy in ring enhancing brain lesions

Aim of the work: To assess and compare the usefulness and efficacy of both diffusion weighted imaging (DWI) and proton magnetic resonance spectroscopy (1HMRS) in brain lesions with ring enhancement in post contrast T1WI and to determine which method is more effective. Subjects and methods: Thirty patients with ring-enhanced brain lesions were classified into 2 groups, abscess group (11 patients) and tumor group (19 patients), were examined using diffusion-weighted imaging (DWI) and H-proton magnetic resonance spectroscopy (1HMRS). Results: Restricted diffusion and low ADC value were seen in 9 (81%) patients of brain abscesses, however, free diffusion and high ADC value were found in 18 (94%) patients with necrotic brain tumor. The abscess group showed aminoacids, acetate and lactate in 9 patients and extra peak of succinate was found in 1 patient; however in the tumor group lactate alone was found in 12 patients, lactate and choline were seen in 5 patients, none of the patients showed amino acids, succinate or acetate. Conclusion: Both DWI and 1HMRS are useful and efficient imaging techniques in ring enhancing brain lesions and differentiate between pyogenic brain abscesses and necrotic tumors, but DWI is accurate, has less imaging time than 1HMRS, also is available in many imaging centers