The Impact of Radiobiologically Informed Dose Prescription on the Clinical Benefit of 90Y SIRT in Colorectal Cancer Patients

The purpose of this study was to establish the dose-response relationship of selective internal radiation therapy (SIRT) in patients with metastatic colorectal cancer (mCRC), when informed by radiobiological sensitivity parameters derived from mCRC cell lines exposed to 90Y. Methods: Twenty-three mCRC patients with liver metastases refractory to chemotherapy were included. 90Y bremsstrahlung SPECT images were transformed into dose maps assuming the local dose deposition method. Baseline and follow-up CT scans were segmented to derive liver and tumor volumes. Mean, median, and D70 (minimum dose to 70% of tumor volume) values determined from dose maps were correlated with change in tumor volume and volumetric RECIST response using linear and logistic regression, respectively. Radiosensitivity parameters determined by clonogenic assays of mCRC cell lines HT-29 and DLD-1 after exposure to 90Y or external beam radiotherapy (EBRT; 6 MV photons) were used in biologically effective dose (BED) calculations. Results: Mean administered radioactivity was 1,469 ± 428 MBq (range, 847-2,185 MBq), achieving a mean absorbed radiation dose to tumor of 35.5 ± 9.4 Gy and mean normal liver dose of 26.4 ± 6.8 Gy. A 1.0 Gy increase in mean, median, and D70 absorbed dose was associated with a reduction in tumor volume of 1.8%, 1.8%, and 1.5%, respectively, and an increased probability of a volumetric RECIST response (odds ratio, 1.09, 1.09, and 1.10, respectively). Threshold mean, median and D70 doses for response were 48.3, 48.8, and 41.8 Gy, respectively. EBRT-equivalent BEDs for 90Y are up to 50% smaller than those calculated by applying protraction-corrected radiobiological parameters derived from EBRT alone. Conclusion: Dosimetric studies have assumed equivalence between 90Y SIRT and EBRT, leading to inflation of BED for SIRT and possible undertreatment. Radiobiological parameters for 90Y were applied to a BED model, providing a calculation method that has the potential to improve assessment of tumor control.

Patterns of Reperfusion and Clinical Findings in Repeat Prostate Artery Embolisation for Recurrent Lower Urinary Tract Symptoms in Patients with Benign Prostatic Hyperplasia

PURPOSE

To present our experience of the patterns of revascularisation of the prostate and efficacy of repeat prostate artery embolisation (rPAE) in patients with recurrence of lower urinary tract symptoms.

MATERIALS AND METHODS

We retrospectively analysed 12 patients who underwent rPAE at a single centre between November 2015 and March 2020. The patients had their intraprocedural angiography and cone beam CT images as well as their pre-procedural CT retrospectively reviewed to establish the patterns of revascularisation. Clinical follow-up occurred at a minimum of 3 months.

RESULTS

11/12 patients (91.6%) had significant international prostate symptom score (IPSS) reduction following rPAE with change in mean IPSS from 18.4 to 8.1 at 3 months (p < 0.0001). Mean prostate volume was reduced by 41.6% (p = 0.03). 8/12 (75%) had a complete clinical success. 20/24 hemiprostates demonstrated revascularisation angiographically, of which 16 (80%) had prostatic arterial supply at rPAE by the main prostatic artery. Other mechanisms of revascularisation included supply from capsular prostatic artery branches and supply from other internal iliac pelvic branches. Unilateral embolisation at rPAE, where bilateral embolisation was not feasible (4/12), resulted in no difference in clinical outcomes compared with bilateral rPAE (p = 0.55).

CONCLUSION

We have found rPAE to be an effective treatment for recurrent lower urinary tract symptoms in patients who had good clinical response to initial PAE. The mechanisms of revascularisation are variable, but most patients that underwent rPAE had recanalisation of their main prostatic artery.

Long-term radiological and histological outcomes following selective internal radiation therapy to liver metastases from breast cancer

Liver metastasis from breast cancer is associated with poor prognosis and is a major cause of early morbidity and mortality. When liver resection is not feasible, minimally invasive directed therapies are considered to attempt to prolong survival. Selective internal radiation therapy (SIRT) with yttrium-90 microspheres is a liver-directed therapy that can improve local control of liver metastases from colorectal cancer. We present a case of a patient with a ductal breast adenocarcinoma, who developed liver and bone metastasis despite extensive treatment with systemic chemotherapies. Following SIRT to the liver, after an initial response, the patient ultimately progressed in the liver after 7 months. Liver tumor histology obtained 20 months after the SIRT intervention demonstrated the presence of the resin microspheres in situ. This case report demonstrates the long-term control that may be achieved with SIRT to treat liver metastases from breast cancer that is refractory to previous chemotherapies, and the presence of microspheres in situ long-term.

Overall survival analysis of the FOXFIRE prospective randomized studies of first-line selective internal radiotherapy (SIRT) in patients with liver metastases from colorectal cancer

3507

Background: The FOXFIRE, SIRFLOX and FOXFIRE-Global (FF-SF-FFG) randomized studies evaluated the efficacy of combining first-line chemotherapy for metastatic colorectal cancer (mCRC) with selective internal radiotherapy (SIRT) using yttrium-90 resin microspheres in patients with liver metastases. The studies were designed for prospective, combined analysis of overall survival (OS). Methods: FF-SF-FFG randomized (1:1) chemotherapy-naïve mCRC patients (performance status 0/1) with liver metastases not suitable for curative resection/ablation. Arm A was oxaliplatin-based chemotherapy (mFOLFOX6/ OxMdG) ± investigator-chosen biologically targeted agent. Arm B was the same systemic therapy (oxaliplatin dose modification) + single treatment SIRT with cycle 1/2 of chemotherapy. Primary tumor in situ and/or limited extra-hepatic metastases were permitted. Minimum sample size was 1075 patients (HR 0.8, 80% power, two-sided 5% significance). Secondary outcomes included PFS, liver-specific PFS and response rate. Apart from safety, outcomes were analysed on intention-to-treat population using meta-analytic methods of pooled individual patient data. Results: Between 2006 and 2014, 1103 patients were randomized in 14 countries. Median age was 63 years (range 23-89); median follow-up 43.3 months. There were 844 deaths. There was no difference in OS (HR 1.04; 95% CI 0.90-1.19, p= 0.609) or PFS (HR 0.90, CI 0.79-1.02, p= 0.108) between Arms. Objective response rate ( p= 0.001) and liver-specific progression (HR 0.51, CI 0.43-0.62, p< 0.001) were significantly more favorable in Arm B. Patients in Arm B had higher risk of non-liver progression as first event (HR 1.98, CI 1.53-2.58, p< 0.001). Grade 3-5 adverse events were more common in Arm B (74.0%) than A (66.5%), p= 0.009. In health status questionnaires, EQ-5D utility scores were not significantly different between Arms at 6, 12 or 24 months. Conclusion: Despite higher response rates and improved liver-specific PFS, the addition of SIRT to first-line oxaliplatin-fluorouracil chemotherapy for patients with liver-only and liver-dominant mCRC did not improve OS or PFS. Clinical trial information: 83867919.

Adenomatous-Dominant Benign Prostatic Hyperplasia (AdBPH) as a Predictor for Clinical Success Following Prostate Artery Embolization: An Age-Matched Case-Control Study

PURPOSE

To investigate the clinical impact of performing prostate artery embolization (PAE) on patients with adenomatous-dominant benign prostatic hyperplasia (AdBPH).

MATERIALS AND METHODS

Twelve patients from the ongoing proSTatic aRtery EmbolizAtion for the treatMent of benign prostatic hyperplasia (STREAM) trial were identified as having AdBPH; defined as two or more adenomas within the central gland of ≥1 cm diameter on multi-parametric MRI (MP-MRI). These patients were age-matched with patients from the STREAM cohort, without AdBPH. Patients were followed up with repeat MP-MRI at 3 months and 1 year. International prostate symptom score (IPSS), international index for erectile function (IIEF), and quality of life assessment from the IPSS and EQ-5D-5S questionnaires were recorded pre-PAE and at 6 weeks, 3 months, and 1 year.

RESULTS

The mean age of patients was 68 (61-76). All patients had PAE as a day-case procedure. The technical success in the cohort was 23/24 (96%). There was a significant reduction in prostate volume following embolization with a median reduction of 34% (30-55) in the AdBPH group, compared to a mean volume reduction of 22% (9-44) in the non-AdBPH group (p = 0.04). There was a significant reduction in IPSS in the AdBPH group following PAE when compared with the control group [AdBPH median IPSS 8 (3-15) vs. non-AdBPH median IPSS 13 (8-18), p = 0.01]. IPSS QOL scores significantly improved in the AdBPH group (p = 0.007). There was no deterioration in sexual function in either group post-PAE.

CONCLUSIONS

This is the first time that AdBPH has been identified as being a predictor of clinical success following PAE.

Optimization of Image Reconstruction for 90Y Selective Internal Radiotherapy on a Lutetium Yttrium Orthosilicate PET/CT System Using a Bayesian Penalized Likelihood Reconstruction Algorithm

Imaging on a γ-camera with ⁹⁰Y after selective internal radiotherapy (SIRT) may allow for verification of treatment delivery but suffers relatively poor spatial resolution and imprecise dosimetry calculation. ⁹⁰Y PET/CT imaging is possible on 3-dimensional, time-of-flight machines; however, images are usually poor because of low count statistics and noise. A new PET reconstruction software using a Bayesian penalized likelihood (BPL) reconstruction algorithm (termed Q.Clear) was investigated using phantom and patient scans to optimize the reconstruction for post-SIRT imaging and clarify whether BPL leads to an improvement in clinical image quality using ⁹⁰Y. Methods: Phantom studies over an activity range of 0.5-4.2 GBq were performed to assess the contrast recovery, background variability, and contrast-to-noise ratio for a range of BPL and ordered-subset expectation maximization (OSEM) reconstructions on a PET/CT scanner. Patient images after SIRT were reconstructed using the same parameters and were scored and ranked on the basis of image quality, as assessed by visual evaluation, with the corresponding SPECT/CT Bremsstrahlung images by 2 experienced radiologists. Results: Contrast-to-noise ratio was significantly better in BPL reconstructions when compared with OSEM in phantom studies. The patient-derived BPL and matching Bremsstrahlung images scored higher than OSEM reconstructions when scored by radiologists. BPL with a β value of 4,000 was ranked the highest of all images. Deadtime was apparent in the system above a total phantom activity of 3.3 GBq. Conclusion: BPL with a β value of 4,000 is the optimal image reconstruction in PET/CT for confident radiologic reading when compared with other reconstruction parameters for ⁹⁰Y imaging after SIRT imaging. Activity in the field of view should be below 3.3 GBq at the time of PET imaging to avoid deadtime losses for this scanner.

High-frequency jet ventilation under general anesthesia facilitates CT-guided lung tumor thermal ablation compared with normal respiration under conscious analgesic sedation

PURPOSE

To determine whether technical difficulty of computed tomography (CT)-guided percutaneous lung tumor thermal ablations is altered with the use of high-frequency jet ventilation (HFJV) under general anesthesia (GA) compared with procedures performed with normal respiration (NR) under conscious sedation (CS).

MATERIALS AND METHODS

Thermal ablation treatment sessions performed with NR under CS or HFJV under GA with available anesthesia records and CT fluoroscopic images were retrospectively reviewed; 13 and 33 treatment sessions, respectively, were identified. One anesthesiologist determined the choice of anesthesiologic technique independently. Surrogate measures of procedure technical difficulty--time duration, number of CT fluoroscopic acquisitions, and radiation dose required for applicator placement for each tumor--were compared between anesthesiologic techniques. The anesthesiologist time and complications were also compared. Parametric and nonparametric data were compared by Student independent-samples t test and χ(2) test, respectively.

RESULTS

Patients treated with HFJV under GA had higher American Society of Anesthesiologists classifications (mean, 2.66 vs 2.23; P = .009) and smaller lung tumors (16.09 mm vs 27.38 mm; P = .001). The time duration (220.30 s vs 393.94 s; P = .008), number of CT fluoroscopic acquisitions (10.31 vs 19.13; P = .023), and radiation dose (60.22 mGy·cm vs 127.68 mGy·cm; P = .012) required for applicator placement were significantly lower in treatment sessions performed with HFJV under GA. There was no significant differences in anesthesiologist time (P = .20), rate of pneumothorax (P = .62), or number of pneumothoraces requiring active treatment (P = .19).

CONCLUSIONS

HFJV under GA appears to reduce technical difficulty of CT-guided percutaneous applicator placement for lung tumor thermal ablations, with similar complication rates compared with treatment sessions performed with NR under CS. The technique is safe and may facilitate treatment of technically challenging tumors.

Microwave ablation of pulmonary malignancies using a novel high-energy antenna system

PURPOSE

To evaluate the technical success, safety, and imaging follow-up of malignant pulmonary nodules treated with a novel high-energy percutaneous microwave ablation (MWA) system.

METHODS

Between July 2010 and September 2011, a total of 23 patients, 12 men, mean age 68 (range 30-87) years with 29 pulmonary malignancies of median diameter 19 (range 8-57) mm, underwent computed tomography (CT)-guided MWA with a 16G microwave needle antenna enabling power up to 180 W. Technical success was defined as needle placement in the intended lesion without death or serious injury. Adequacy of ablation was assessed at 24 h on contrast-enhanced CT. Circumferential solid or ground glass opacification >5 mm was used to define an ideal ablation. Local tumor recurrence was assessed at 1, 3, and 6 months after ablation on contrast-enhanced CT.

RESULTS

MWA was technically successful in 93 % (n = 27). Mean ablation duration was 3.6 (range 1-9) min. Ten patients (43 %) developed a pneumothorax as a result of the MWA; only 3 (13 %) required placement of a chest drain. Thirty-day mortality rate was 0 %. The mean hospital stay was 1.5 (range 1-7) days. A total of 22 lesions (75 %) were surrounded by ≥5 mm ground glass or solid opacification after the procedure. At a median follow-up of 6 months, local recurrence was identified in 3 out of 26 lesions, giving a local control rate of 88 %.

CONCLUSION

MWA using a high-power antenna of pulmonary malignancies is safe, technically achievable, and enables fast ablation times.

StarClose Vascular Closure Device: Prospective Study on 222 Deployments in an Interventional Radiology Practice

The StarClose device (Abbott Vascular Devices; Abbott Laboratories, Redwood City, CA) utilizes an externally placed Nitinol clip to achieve arterial closure following femoral artery puncture. The objectives of this study were to assess the efficacy and complications of the StarClose device in patients undergoing interventional radiological procedures. Preprocedural clotting status, pulse and blood pressure, severity of vessel calcification, sheath size, and time to deployment were recorded. Postdeployment complications immediately postprocedure, at 1 h, at 2 h, and at 1 week were recorded. A duplex scan was performed in the first 10 patients to assess any immediate vascular complications. Deployments were successful in 96% achieving immediate hemostasis. Mean deployment time was 48 s. There were no major complications. The StarClose device was found to have a high technical and clinical efficacy.

Thrombin injection for acute hemorrhage following angiography

Femoral arterial puncture is the main access for diagnostic and therapeutic intervention in vascular disease. Significant complications are unusual and include uncontrolled bleeding which usually requires surgery. We report the use of ultrasound-guided thrombin injection that prevented any immediate need for surgery in 2 cases of uncontrolled bleeding following femoral arteriography. Clinical presentations and treatment are reported, together with a review of the literature.

Anatomic and functional imaging of metastatic carcinoid tumors

Carcinoid tumors are a fascinating group of neuroendocrine neoplasms that develop either sporadically or as part of an inheritable syndrome. Many tumors arise in the bronchopulmonary or gastrointestinal tract, but a neuroendocrine tumor can arise in almost any organ. The tumors have varied malignant potential depending on the site of their origin, and the clinical manifestations often are nonspecific. Metastases may be present at the time of diagnosis, which often occurs at a late stage of the disease. Imaging plays a pivotal role in the localization and staging of neuroendocrine tumors and in monitoring the treatment response. Imaging is often challenging, and a combination of anatomic and functional techniques is usually required, depending on the tumor type and location. Techniques include ultrasonography, barium studies, endoscopy, computed tomography, magnetic resonance imaging, somatostatin receptor scintigraphy, iobenguane scintigraphy, and, in select cases, positron emission tomography. Coregistration of structural and functional images is often of incremental value for accurate localization of the primary tumor and any meta-static disease. Radiologists must understand the contribution of each imaging modality in the assessment of different neuroendocrine tumors. In addition, knowledge of the optimal technique for each radiologic and radionuclide imaging examination is essential. Familiarity with the protean imaging appearances of both primary and metastatic disease is essential for accurate staging, treatment monitoring, and surveillance. Finally, an understanding of the wide variety of treatment options for patients with carcinoid tumors is vital for optimal management.

Diagnostic imaging of and radiologic intervention for bovine ureter grafts used as a novel conduit for hemodialysis fistulas

OBJECTIVE

The objectives of our study were to review the appearances on diagnostic imaging and amenability to imaging-guided intervention of a novel bovine ureter graft (Syner-Graft 100 [SG 100]) for use as a conduit for hemodialysis fistulas.

CONCLUSION

The SG 100 shows initial promise as a conduit for hemodialysis fistulas in patients with difficult vascular access. The SG 100 has characteristic appearances on diagnostic imaging and is prone to similar pathologic processes that affect autogenous venous and synthetic grafts. These grafts are readily amenable to imaging-guided percutaneous intervention, which plays a major role in prolonging graft function.

Angioseal versus manual compression for haemostasis following peripheral vascular diagnostic and interventional procedures—A randomized controlled trial

The aim of this study was to compare the angioseal device to manual compression for femoral artery puncture following peripheral vascular procedures, in the context of day case vascular procedures. One hundred patients were prospectively randomised to haemostasis using the angioseal device or manual compression following arterial puncture for peripheral vascular diagnostic or intervention procedures. Data were collected regarding time to haemostasis and complications immediately post-procedure, at 1h, 2h and at 1 week. There were 50 patients in each group. There were no significant differences in demographic variables, or in complication rates immediately, at 1h, 2h and at 1 week (Chi-squared). The only significant difference between the two groups was time to haemostasis. The mean time to haemostasis in the compression group was 10.6 min and 2.0 min in the angioseal group (t-test p<0.0001). In conclusion, no significant differences in complications were found between manual compression and angioseal. However, there was a significant difference in time to haemostasis.

Thromboelastographic Changes Following Nonionic Contrast Medium Injection During Transfemoral Angiography in Patients with Peripheral Arterial Occlusive Disease

BACKGROUND/PURPOSE

Patients with peripheral arterial occlusive disease (PAOD) are known to be systemically hypercoagulable and there is concern that exposing them to contrast media during angiography may exacerbate that thrombotic tendency. Many in vitro studies in which blood is exposed to contrast media suggest that nonionic contrast medium (NICM) has a weaker anticoagulant effect than ionic contrast medium (ICM) and some studies suggest that NICM can lead to activation of coagulation thus increasing the risk of thrombotic events where it is employed. We have looked at the changes in coagulation adjacent to the site of contrast injection/potential angioplasty to determine the magnitude of change locally.

METHODS

We measured changes in the coagulability of aortic blood samples immediately before and within 2 min after injection of the last bolus of iohexol (NICM) prior to any intervention procedure in 30 patients with PAOD. Samples were analyzed using thromboelastography (TEG) to identify changes in the coagulability of the aortic blood samples.

RESULTS

TEG tracings of samples taken from the aorta after injection of NICM showed a significant increase in R time (time to fibrin formation) (p = 0.036) and in k time (dynamics of clot formation) (p = 0.028) and a reduction in Angle (decreased acceleration of fibrin build-up) (p = 0.013), Maximal amplitude (MA) (reduced ultimate clot strength) (p = 0.018) and Coagulation Index (CI) (p = 0.032).

CONCLUSION

These changes in TEG parameters show that the local effect of NICM is a reduction in coagulation activity rather than the activation suggested by some previous studies.

Percutaneous abscess drainage in the UK: A national survey and single centre study

AIM

To establish the current practice for management of radiologically placed percutaneous drains for abdominal sepsis in the UK and prospectively study the management of radiologically placed drains at our institution.

METHOD

A questionnaire on the management of radiologically placed drains was sent to all radiology departments on a Royal College of Radiologists database. We prospectively followed all drains placed by our radiology department for drainage of abdominal collections, over a 7-month period.

RESULTS

A total of 210 questionnaires were sent for the national survey, of these 117 were returned (55.7%). The majority of departments (70.5%) reported that after drain insertion the clinical team took over daily management. Just over 5% of departments either formally managed the drain or obtained final outcome data. From October 2003 to April 2004 we followed 63 consecutive drains placed in 45 patients, for abdominal sepsis. Thirty-nine drains (61.9%) were curative and 17 (26.9%) drains failed. Three drains (4.8%) were placed for palliation, and four drains (6.4%) were placed in order to temporise prior to surgery. Forty-three (68.3%) drains had a successful primary outcome: success after secondary percutaneous abscess drainage (PAD) improved to 46 (73.0%) drains. Two (3%) major complications occurred.

CONCLUSIONS

The current approach in the UK to management of radiologically placed drains differs significantly from that practised in the USA. The most common type of support offered by radiology departments in the UK is of informal advice and follow-up, with the clinical team managing the patient's drain. Observations in our hospital highlighted problems relating to drain management that may impact on the success of PAD. We suggest that more formal radiological support after PAD would improve communication and potentially improve outcomes.

Seizures after aneurysmal subarachnoid hemorrhage treated with coil embolization

OBJECTIVE

We sought to determine the incidence of seizures among patients treated with endovascular coil embolization for ruptured intracranial aneurysms because data on which to base antiepileptic drug (AED) prescriptions and advice to patients regarding driving motor vehicles and other high-risk activities are currently lacking.

METHODS

We conducted a single-institute, single-operator observational study of 243 patients referred for endovascular treatment after aneurysmal subarachnoid hemorrhage. Prospective data collection was performed, and all successfully treated patients were followed. The incidence of seizures was compared with published surgical data, and logistic regression analysis of potential clinical associations was performed. Patients were followed for up to 7.7 years (mean follow-up period, 21.9 mo).

RESULTS

Ictal seizures occurred at the time of subarachnoid hemorrhage in 26 (11%) of 243 patients and correlated with middle cerebral artery aneurysm location, loss of consciousness at ictus, and AED prescription. No patients experienced periprocedural seizures during their hospitalization. Seven of 233 successfully treated patients (3%) experienced seizures more than 30 days after treatment: late seizures occurred de novo in four patients (1.7%) and in three patients (1.4%) were caused by preexisting epilepsy. Two patients (0.85%) who had de novo seizures developed epilepsy. Late seizures correlated with a history of previous seizures, the presence of a cerebrospinal fluid shunt, and the use of AEDs.

CONCLUSION

The low incidence of seizures does not justify the use of prophylactic AED therapy after aneurysmal subarachnoid hemorrhage in patients treated solely with coil embolization, nor does it justify subsequent restrictions on the driving of motor vehicles if the patient is otherwise fit to drive.

Radiological intervention to the iliac segments for patients with claudication and coexistent significant infrainguinal disease

Background

The policy with regard to patients with lifestyle-limiting intermittent claudication is to investigate with duplex ultrasonography and then to treat suitable lesions in the aortoiliac system with balloon angioplasty with or without stenting. In those with coexistent infrainguinal disease, further management is conservative. The aim of this study was to assess the outcome of iliac intervention in this group of patients.

Methods

Over 30 months 600 patients with intermittent claudication were assessed; 110 subsequently underwent balloon angioplasty (87 aortoiliac and 23 infrainguinal). Of those undergoing aortoiliac angioplasty 47 also had significant infrainguinal disease. These 47 had a median claudication distance of 80 m and median maximum walking distance 180 m. They underwent angioplasty of 61 arterial segments (one aorta, 32 common iliac, 28 external iliac), with 11 stents deployed in eight patients. There were no immediate complications and a technically satisfactory result was obtained in all but one patient. All patients were reassessed at 6 weeks.

Results

The Table gives the findings at 6 weeks.

Fifteen patients (32 per cent) had a pain-free walking distance greater than 450 m and a further two were limited by angina rather than claudication. Overall the 47 patients had a median claudication distance of 270 m and median maximum walking distance of 420 m.

Conclusion

Even in the presence of significant infrainguinal disease, angioplasty in the aortoiliac segments at least doubles the claudication distance in 70 per cent of patients, and appears to be safe. Radiological intervention in these patients is worthwhile.

The timing and frequency of complications after peripheral percutaneous transluminal angioplasty and iliac stenting: is a change from inpatient to outpatient therapy feasible?

PURPOSE

A prospective study was performed to assess the frequency and timing of complications after transluminal angioplasty and stent placement with a view to changing our practice and performing these procedures on an outpatient basis.

METHOD

A total of 266 angioplasties and 51 stent deployments were attempted on 240 consecutive patients. Immediate complications were documented by the radiologists. The timing and nature of any complications during and beyond the first 24 hr were reported by the vascular surgeons.

RESULTS

There were 14 complications in 240 patients, giving a complication rate of 4.8% per vessel segment dilated. There were five major and nine minor complications. Eighty-six percent of complications were evident before the patient had left the angiography suite. All complications were evident within 4.5 hr of the procedure.

CONCLUSION

The timing of complications suggests it would be reasonable to perform percutaneous transluminal angioplasties and iliac stenting on an outpatient basis in suitable patients.

The frequency and significance of silent myocardial ischemia due to hyoscine butylbromide use in peripheral angiography

PURPOSE

Hyoscine-N-butylbromide (HB) is an anticholinergic drug used in digital subtraction angiography of the aortoiliac region because it decreases bowel gas movement artifact. HB also causes an increase in heart rate. We investigated whether this could cause silent myocardial ischemia (SMI) in susceptible patients during peripheral angiography.

METHODS

Thirty-six patients undergoing peripheral angiography were randomized into two groups, with 17 patients receiving 20 mg HB intraarterially during the angiogram and 19 patients receiving no drug. All patients were fitted with a Holter monitor that recorded the electrocardiogram before, during, and after the angiogram. Heart rate trends and ST segments were then analyzed.

RESULTS

Patients given HB had a statistically significant rise in heart rate compared with the control group. Although the difference was not statistically significant, two (12%) patients receiving HB had procedural ST depression compared with none in the control group. Pre- and postprocedural episodes of ST depression were common, occurring in 41% of patients receiving HB and 37% of patients receiving no drug, and were associated with an increase in heart rate.

CONCLUSION

The infrequent episodes of procedural SMI, potentially caused by the positive chronotropic effects of HB, are probably insignificant when compared with the high frequency of SMI episodes occurring outside the procedure.

Giant fusiform basilar artery aneurysm: endovascular treatment by flow reversal in the basilar artery

We report a patient presenting with subarachnoid haemorrhage due to rupture of a giant fusiform aneurysm of the proximal basilar artery. The aneurysm was successfully treated by reversing blood flow in the basilar artery by balloon occlusions of both vertebral arteries proximal to the posterior inferior cerebellar artery origins. Substantial thrombosis and regression of the aneurysm was evident 4 months later.

Radiological evaluation and management of malfunctioning central venous catheters

Central venous catheters provide an important means of long-term vascular access in a variety of clinical situations. Catheter placement and evaluation is now forming an increasing part of the workload of interventional radiologists. This review presents an overview of malfunctioning central venous catheters. We outline the causes of catheter related problems and discuss the treatment options. We include examples of catheter malfunction resulting from malposition, displacement, kinking and occlusion.

A phase II study of mitomycin C and oral etoposide for advanced adenocarcinoma of the upper gastrointestinal tract

BACKGROUND

Mitomycin C and etoposide have both demonstrated activity against gastric carcinoma. Etoposide is a topoisomerase II inhibitor with evidence for phase-specific and schedule-dependent activity.

PATIENTS AND METHOD

Twenty-eight consecutive patients with advanced upper gastrointestinal adenocarcinoma were treated with intravenous (i.v.) bolus mitomycin C 6 mg/m2 on day 1 every 21 days to a maximum of four courses. Oral etoposide capsules 50 mg b.i.d. (or 35 mg b.i.d. liquid) were administered days 1 to 10 extending to 14 days in subsequent courses if absolute neutrophil count > 1.5 x 10(9)/l on day 14 of first course, for up to six courses.

RESULTS

Twenty-six patients were assessed for response of whom 12 had measurable disease and 14 evaluable disease. Four patients had a documented response (one complete remission, three partial remissions) with an objective response rate of 15% (95% confidence interval (95% CI) 4%-35%). Eight patients had stable disease and 14 progressive disease. The median survival was six months. The schedule was well tolerated with no treatment-related deaths. Nine patients experienced leucopenia (seven grade II and two grade III). Nausea and vomiting (eight grade II, one grade III), fatigue (eight grade II, two grade III) and anaemia (seven grade II, two grade III) were the predominant toxicities.

CONCLUSION

This out-patient schedule is well tolerated and shows modest activity in the treatment of advanced upper gastrointestinal adenocarcinoma. Further studies using protracted schedules of etoposide both orally and as infusional treatment should be developed.

Pictorial review: MR imaging of neuronal migration anomalies

Neuronal migration anomalies form a spectrum of congenital brain malformations with a variety of clinical manifestations. The widespread use of MRI in the investigation of neurological symptoms, and particularly in the imaging of epilepsy, has made the correct recognition and interpretation of these disorders important. This pictorial summary describes the typical clinical features and the MR appearances of this group of conditions. For a more detailed review which includes pathological correlation, the reader should refer to an excellent article by Barkovitch and colleagues (Barkovitch A.J., Gressens P, Evrard P. Formation, maturation and disorders of brain neocortex.

Patient radiation doses from enteroclysis examinations

Data relating to patient dose have been acquired for enteroclysis examinations (small bowel enemas) performed at the John Radcliffe Hospital, Oxford, on 23 adult patients. Dose-area products, fluoroscopy times and the number of radiographs taken are used to compare the examination procedure at the John Radcliffe Hospital with enteroclysis and barium follow-throughs performed elsewhere. The mean dose-area product for the 23 examinations was 6.8 Gy cm2 and the mean effective dose was estimated to be 1.5 mSv. These doses are intermediate between those arising from barium meals and barium enemas performed in the same room.

Lineage analysis reveals neurotransmitter (GABA or glutamate) but not calcium-binding protein homogeneity in clonally related cortical neurons

Studies of cell lineage in the rat cerebral cortex have provided new insights into the mechanisms of neuronal and glial determination. They have shown that clonally related cells, marked with retrovirus injection at embryonic day 16 (E16), express the same glial or neuronal phenotype, suggesting that separate progenitors for each of these cell phenotypes exist in the ventricular zone at that stage of corticogenesis. However, it is not known if such committed progenitors are present in the ventricular zone before E16. Another important question concerns which neurochemical features are shared by clonally related cells of the adult cerebral cortex. In this study we have addressed the first question by injecting a retroviral vector expressing beta-galactosidase into the telencephalic ventricles of rat embryos at different stages (E14-E19). In order to classify clonally related neurons in the cerebral cortex of these rats, we have used postembedding immunohistochemistry for the amino acid neurotransmitters glutamate, aspartate, and GABA. Glutamate and GABA immunoreactivity marked nonoverlapping populations of cells that corresponded to the pyramidal and nonpyramidal neuron types of the rat cerebral cortex. Clonally related neurons, marked by retrovirus injection at any day between E14 and E19, homogeneously expressed one or other phenotype and accordingly displayed glutamate or GABA immunoreactivity. This finding indicates that committed progenitor cells for pyramidal and nonpyramidal neurons are present in the ventricular zone before E16. To investigate whether lineage dictates other features in clonally related neurons, we performed an immunohistochemical analysis for the calcium-binding proteins calbindin, parvalbumin, and calretinin in clusters of clonally related nonpyramidal neurons. The same calcium-binding protein was rarely found in members of the same cluster, suggesting that lineage does not control the expression of calcium-binding proteins in cortical nonpyramidal neurons. As a result of examining a large number of clonally related neurons from brains injected at different ages, we observed remarkable differences in number and laminar distribution of pyramidal and nonpyramidal neurons marked with retrovirus. Clusters of nonpyramidal neurons were usually composed of two or three cells, and resided in the cortical layers that were just being generated at the time of injection. Clusters of pyramidal neurons were larger and dispersed in several layers in the earlier injections; their size and laminar distribution were progressively reduced for later injections. These observations suggest the existence of different mechanisms that generate the pyramidal and nonpyramidal neurons of the cerebral cortex.

Plants as sources of antimalarial drugs, Part 4: Activity of Brucea javanica fruits against chloroquine-resistant Plasmodium falciparum in vitro and against Plasmodium berghei in vivo

Extracts of Brucea javanica fruit have been prepared and monitored for their in vitro and in vivo antiplasmodial activities. The antimalarial activity of the fruit was found to be attributable to its quassinoid constituents. Nine of the quassinoids possessed in vitro IC50 values between 0.046-0.0008 microgram/ml against the chloroquine resistant Plasmodium falciparum strain (Kl) tested. The two quassinoid glycosides tested were considerably less active in vitro than the aglycones. Four quassinoids were found to possess activity in vivo against Plasmodium berghei infections in mice after oral dosing. All five quassinoids tested in vivo showed some toxicity.

Plants as sources of antimalarial drugs: in vitro antimalarial activities of some quassinoids

Fourteen quassinoids, obtained from simaroubaceous plants, were tested for in vitro antimalarial activity. All of these inhibited the incorporation of [3H]hypoxanthine into Plasmodium falciparum in vitro at concentrations below 0.41 microgram ml-1. The two most potent quassinoids, bruceantin and simalikalactone D, showed 50% inhibitory concentration values of 0.0008 and 0.0009 microgram ml-1, respectively. The results are compared with the antiamoebic, antileukemic, and cytotoxic activities of these compounds reported in the literature.