Wall suction-assisted image-guided thoracentesis: a safe alternative to evacuated bottles.

AIM: To compare the safety of evacuated bottle-assisted thoracentesis with wall suction-assisted thoracentesis. MATERIALS AND METHODS: An institutional review board-approved, Health Insurance Portability and Accountability Act-compliant retrospective study of 161 consecutive patients who underwent 191 evacuated bottle-assisted thoracenteses from 1 January 2012 to 30 September 2012, and 188 consecutive patients who underwent 230 wall suction-assisted thoracenteses from 1 January 2013 to 30 September 2013 was conducted. All procedures used imaging guidance. Primary diagnosis, age, gender, total fluid volume removed, and adverse events (AE) up to 30 days post-procedure were recorded and graded using Common Terminology Criteria for Adverse Events 4.0 (CTCAE)2. RESULTS: Overall AE rates were 42.9% (82/191) for the evacuated bottle group and 19.6% (45/230) for the wall suction group (p<0.0001). Grade I AE occurred more commonly in the evacuated bottle group than in the wall suction group, [41.9% (80/191) and 18.3% (42/230)], respectively (p<0.0001). No significant differences were observed in grade 2 [0.5% (1/191) and 0% (0/230), p=0.45] or grade 3 AE [0.5% (1/191) and 1.3% (3/230), p=0.63] between the evacuated bottle and wall suction groups, respectively. No grade 4 or 5 AE occurred. Excluding transient chest pain and cough, there was no statistical difference in overall AE rate between the evacuated bottle and wall suction groups [11% (21/191) and 8.3% (19/230), p=0.4]. CONCLUSION: Image-guided thoracentesis performed with wall suction is safe when compared to evacuated bottles. The use of wall suction, in comparison to evacuated bottles, may decrease the incidence of transient chest pain or cough.

Breath-hold PET/CT-guided tumour ablation under general anaesthesia: accuracy of tumour image registration and projected ablation zone overlap.

AIM: To assess single-breath-hold combined positron-emission tomography/computed tomography (PET/CT) for accuracy of tumour image registration and projected ablation volume overlap in patients undergoing percutaneous PET/CT-guided tumour-ablation procedures under general anaesthesia. MATERIALS AND METHODS: Eight patients underwent 12 PET/CT-guided tumour-ablation procedures to treat 20 tumours in the lung, liver, or adrenal gland. Using breath-hold PET/CT, the centre of the tumour was marked on each PET and CT acquisition by four readers to assess two- (2D) and three-dimensional (3D) spatial misregistration. Overlap of PET and CT projected ablation volumes were compared using the Dice similarity coefficient (DSC). Interobserver differences were assessed with repeated measure analysis of variance (ANOVA). Technical success and local progression rates were noted. RESULTS: Mean tumour 2D PET/CT misregistrations were 1.02 mm (range 0.01-5.02), 1.89 (0.03-7.85), and 3.05 (0-10) in the x, y, and z planes. Mean 3D misregistration was 4.4 mm (0.36-10.74). Mean projected PET/CT ablation volume DSC was 0.72 (±0.19). No significant interobserver differences in 3D misregistration (p=0.73) or DSC (p=0.54) were observed. Technical success of ablations was 100%; one (5.3%) of 19 tumours progressed. CONCLUSION: Accurate spatial registration of tumours and substantial overlap of projected ablation volumes are achievable when comparing PET and CT acquisitions from single-breath-hold PET/CT. The results suggest that tumours visible only at PET could be accurately targeted and ablated using this technique.

PET/CT-guided percutaneous liver mass biopsies and ablations: targeting accuracy of a single 20 s breath-hold PET acquisition.

AIM: To determine whether a single 20 s breath-hold positron-emission tomography (PET) acquisition obtained during combined PET/computed tomography (CT)-guided percutaneous liver biopsy or ablation procedures has the potential to target 2-[(18)F]-fluoro-2-deoxy-d-glucose (FDG)-avid liver masses as accurately as up to 180 s breath-hold PET acquisitions. MATERIALS AND METHODS: This retrospective study included 10 adult patients with 13 liver masses who underwent FDG PET/CT-guided percutaneous biopsies (n = 5) or ablations (n = 5). PET was acquired as nine sequential 20 s, monitored, same-level breath-hold frames and CT was acquired in one monitored breath-hold. Twenty, 40, 60, and 180 s PET datasets were reconstructed. Two blinded readers marked tumour centres on randomized PET and CT datasets. Three-dimensional spatial localization differences between PET datasets and either 180 s PET or CT were analysed using multiple regression analyses. Statistical tests were two-sided and p < 0.05 was considered significant. RESULTS: Targeting differences between 20 s PET and 180 s PET ranged from 0.7-20.3 mm (mean 5.3 ± 4.4 mm; median 4.3) and were not statistically different from 40 or 60 s PET (p = 0.74 and 0.91, respectively). Targeting differences between 20 s PET and CT ranged from 1.4-36 mm (mean 9.6 ± 7.1 mm; median 8.2 mm) and were not statistically different from 40, 60, or 180 s PET (p = 0.84, 0.77, and 0.35, respectively). CONCLUSION: Single 20 s breath-hold PET acquisitions from PET/CT-guided percutaneous liver procedures have the potential to target FDG-avid liver masses with equivalent accuracy to 180 s summed, breath-hold PET acquisitions and may facilitate strategies that improve image registration and shorten procedure times.

Incidence, appropriateness, and consequences of recommendations for additional imaging tests in oncological PET/CT reports.

AIM: To assess the incidence, appropriateness, and outcomes of recommendations for additional imaging tests (RAI) in oncological combined 2-[(18)F]-fluoro-2-deoxy-d-glucose positron-emission tomography and computed tomography (FDG-PET/CT) reports. MATERIAL AND METHODS: In this retrospective study, conducted with institutional review board approval, the first oncological FDG-PET/CT reports in 2008 for 250 consecutive patients were reviewed to identify RAI. PET/CT reports containing RAI were retrospectively reviewed by two blinded readers. PET/CT findings prompting RAI, appropriateness of RAI, results of additional imaging tests actually performed, and the ultimate clinical significance of findings prompting RAI were recorded. Confirmation of clinical significance required pathology confirmation, unequivocal imaging progression, imaging stability for 12 months, or clinical follow-up for 24 months or end of life. RESULTS: Eighty-four RAI were identified for 88 PET/CT findings in 29.6% (74/250) of PET/CT reports, of which 51.2% (43/84) were deemed unnecessary by reviewers. Referring clinicians only followed 31% (26/84) of RAI by requesting additional imaging tests, and these tests resolved the PET/CT question in 76.9% (20/26) of those cases. Only 11.4% (10/88) of all findings prompting RAI proved to be clinically significant. Only 4.7% (2/43) of RAI deemed unnecessary by reviewers and 5.2% (3/58) of RAI not pursued by clinicians were found to be clinically significant; however, PET/CT alone was sufficient for diagnosis or guiding appropriate clinical management in each of these cases. CONCLUSION: RAI were found in 29.6% of oncological PET/CT reports. No potential adverse impact on patient management or outcome, by not issuing or following RAI, was identified in the 51.2% of RAI deemed unnecessary by study readers or in the 69% of RAI not pursued by referring clinicians.

Detection of small, functional islet cell tumors in the pancreas: selection of MR imaging sequences for optimal sensitivity.

PURPOSE: To determine the sensitivity and specificity of magnetic resonance (MR) imaging for depicting pancreatic small, functional islet cell tumors and the minimum number of sequences for expedient diagnosis. MATERIALS AND METHODS: Twenty-eight patients clinically suspected to have functional islet cell tumors underwent T1- and T2-weighted spin-echo (SE) MR imaging with and without fat suppression, T2-weighted fast SE imaging, and spoiled gradient-echo (GRE) imaging before and after injection of gadopentetate dimeglumine. Sensitivity, specificity, and the best and minimum number of sequences for definitive diagnosis were determined. RESULTS: MR images depicted proved islet cell tumors in 17 of 20 patients (sensitivity, 85%). Images were true-negative in eight patients with negative follow-up examination results for more than 1 year. Specificity was 100%; positive predictive value, 100%; and negative predictive value, 73%. Among 20 patients with tumor, T1-weighted SE images with fat suppression and nonenhanced spoiled GRE images each showed lesions in 15 (75%); T2-weighted conventional SE with fat suppression, in 13 (65%); gadolinium-enhanced spoiled GRE, in 12 (60%); and T2-weighted fast SE, in seven of 10 patients (70%). CONCLUSION: MR imaging accurately depicts small islet cell tumors. T2-weighted fast SE and spoiled GRE sequences usually suffice. Gadolinium-enhanced sequences are needed only if MR imaging results are equivocal or negative.

Abdominal CT following liver transplantation.

Computed tomography (CT) is one of several imaging modalities employed in the evaluation of complications following orthotopic liver transplantation. Abdominal CT scans were performed in 92 (48%) of the first 190 liver transplant patients at our institution. These studies were retrospectively reviewed to determine the indications for CT in this population and to determine the incidences of the various CT findings. The major indication (70%) was detection of bile leakage, hemorrhage, or abscess. The role of CT was primarily to discover such abnormal fluid collections and guide their percutaneous drainage. This article describes a wide spectrum of common and uncommon findings following liver transplantation and illustrates their CT features.

Transient cortical blindness following cerebral angiography.

Transient cortical blindness following cerebral angiography was previously assumed to result from embolism or other factors impairing cortical perfusion during angiography. Contrast medium-induced disruption of the blood-brain barrier and a direct neurotoxic effect by contrast media have been proposed as a potential mechanism of neurotoxicity. Support of this concept has been provided by reports that demonstrate blood-brain barrier damage with postangiography computerized tomography in patients experiencing various acute neurologic sequelae of cerebral angiography including one case of transient cortical blindness. We report a case of transient cortical blindness following cerebral angiography in which computerized tomography documents blood-brain barrier disruption limited to the occipital lobes.

Primary intracranial ependymoblastoma presenting as spinal cord compression due to metastasis.

A primary intracranial ependymoblastoma presented only with symptoms of spinal cord compression due to metastatic spread of the tumor via the leptomeninges. Such a presentation is very rare among primary neoplasms of the central nervous system (CNS) and unique among the 12 previously reported ependymoblastomas. The previous cases all arose as primary brain tumors and several were remarkable for extensive leptomeningeal spread of the tumor. These observations and the presentation of our patient suggest that a histological diagnosis of ependymoblastoma of the spinal cord, with or without symptoms of intracranial tumor, should suggest that an intracranial primary lesion might be present.