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Aim: To compare the effectiveness and safety of pharmacological thrombolysis and mechanical thrombectomy., Material and Methods: This review was conducted in accordance with the PRISMA guidelines. Pooled proportions and subgroup analysis were calculated for primary and secondary patency rates, technical success, clinical success, major and minor complications rates., Results: This systematic review identified a total of 6,492 studies of which 17 studies were included for analysis. A total of 1,089 patients comprising 451 (41.4 %) and 638 (58.6 %) patients who underwent thrombolysis and mechanical thrombectomy procedures, respectively, were analysed. No significant differences were observed between thrombolysis and mechanical thrombectomy procedures in terms of technical success, clinical success, major and minor complications rates, primary and secondary patency rates; however, subgroup analysis of overall arteriovenous fistulas (AVFs) and arteriovenous grafts (AVGs) demonstrated a significantly higher rate of major complications within the AVF group (p=0.0248)., Conclusion: The present meta-analysis suggests that pharmacological thrombolysis and mechanical thrombectomy procedures are similarly effective and safe; however, AVFs are subject to higher major complications compared to AVGs., (Copyright © 2024 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Aim: To examine the relationship between catheter tip location and catheter dysfunction in the context of tunnelled central venous catheters (CVCs) for haemodialysis., Materials and Methods: This was a retrospective study of 993 haemodialysis patients who underwent insertion of tunnelled CVCs of step-tip design via the right internal jugular vein (IJV). Based on intra-procedural radiographs, the catheter tip was characterised as being in the superior vena cava (SVC), cavo-atrial junction (CAJ), or deep right atrium (DRA). Patients were tracked for 90 days post-procedure for complications resulting in catheter replacement, and these were compared between cohorts. Statistical analysis was performed with Pearson's chi-square and Fisher's exact tests for categorical variables and two-sample t-test and one-way analysis of variance (ANOVA) for continuous variables., Results: Ninety-five patients (9.6%) experienced catheter dysfunction necessitating replacement within 90 days of insertion. Tip location in SVC was associated with lower occurrence of catheter dysfunction (1.9%) as compared with the CAJ (8%) and DRA (11%; p=0.049). Catheter replacement due to other complications (catheter-associated bacteraemia, cuff dislodgement, exit-site infection, external catheter damage) showed no statistically significant relation to location of the CVC tip., Conclusion: When utilising tunnelled CVCs with a step-tip design inserted via the right IJV, location of the catheter tip in the SVC is associated with reduced occurrence of catheter dysfunction as compared to either the CAJ or DRA., (Copyright © 2022 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Aim: To evaluate the ultra-lose dose imaging protocol (ULDP), compared to the standard low-dose imaging protocol (LDP), which are used for haemodialysis access, in terms of radiation exposure and image quality., Material and Methods: This was a single-centre, institutional review board-approved, prospective, double-blinded randomised controlled study to compare radiation exposure and image quality of the ULDP and LDP. Ten proceduralists, two radiographers, and 11 nurses were enrolled. Radiation exposure during 80 procedures (40 angioplasties and 40 thrombolysis) was recorded (direct radiation to patients from protocol report and scattered radiation to participants from the RaySafe i2 real-time dosimetry system). Baseline characteristics of procedure were recorded. Image quality was assessed subjectively using questionnaires based on the five-point Likert scale after each procedure., Results: Compared with LDP, the use of ULDP was associated with a significantly lower rate of radiation exposure to proceduralists, patients, and scrub nurses (0.506±0.430 versus 0.847±0.965 μSv/s, p=0.044; 0.571±1.284 versus 1.284±1.007 mGy/s, p<0.001; and 0.052±0.071 versus 0.141±0.185 μSv/s, p=0.005, respectively). No significant difference in image quality or duration of procedure was observed (all p values >0.05)., Conclusion: Compared with LDP, the use of ULDP was associated with a significantly lower rate of radiation exposure to proceduralists, patients, and scrub nurses without compromising the image quality or duration of procedure., (Copyright © 2020 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Coronavirus disease 2019 (COVID-19) has spread fast and extensively around the world, with significant mortality and morbidity. As this is a respiratory infection, chest radiography and computed tomography (CT) are important imaging techniques in the work-up of this disease. Given its highly infectious nature, cross-infection within the healthcare setting and radiology departments needs to be addressed actively and prevented. We describe the response of radiology departments in Singapore to this pandemic, in terms of diagnosis, re-configuration of the department, re-organisation and segregation of staff, infection control, managerial, and leadership issues., (Copyright © 2020 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Rationale and Purpose: To determine the usefulness of the Choyke questionnaire with a creatinine point-of-care test (POCT) to detect impaired renal function amongst outpatients receiving intravenous iodinated contrast in a tertiary centre., Materials and Methods: Between July and December 2012, 1361 outpatients had their serum creatinine determined by POCT and answered the Chokye questionnaire just before their examination., Results: Four hundred and eighty (35.2%) patients had at least one 'Yes' response. Forty-four patients (3.2%) had estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m(2) and 14 patients (1.0%) have eGFR <45 mL/min/1.73 m(2). Sensitivity, specificity, positive predictive value and negative predictive value of the Choyke criteria in detecting patients with eGFR <60 mL/min/1.73 m(2) are respectively: 65.9%, 65.8%, 6.0% and 98.3% and to detect eGFR <45 mL/min/1.73 m(2): 92.9%, 65.3%, 2.7% and 99.9%. Only 'Yes' responses to 'Have you ever been told you have renal problems?' and 'Do you have diabetes mellitus?' were statistically significant in predicting eGFR <45 mL/min/1.73 m(2), with odds ratio 98.7 and 4.4 respectively., Conclusion: The Choyke questionnaire has excellent sensitivity and moderate-to-good specificity in detecting patients with <45 mL/min/1.73 m(2), below this level it has been shown that risk of contrast induced nephropathy increases significantly, making it an effective screening tool. Also the use of POCT can potentially reduce waiting time., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Epidemiological evidence has linked the development and progression of several cancers including melanoma with obesity. However, whether obesity impinges on responses of cancer cells to treatment remains less understood. Here we report that human adipocytes contribute to resistance of melanoma cells to various therapeutic agents. Exposure to media from adipocyte cultures (adipocyte media) increased cell proliferation and reduced sensitivity of melanoma cells to apoptosis induced by diverse chemotherapeutic drugs, including the DNA-damaging drug cisplatin, the microtubuletargeting agent docetaxel, and the histone deacetylase inhibitor SAHA. This was associated with increased activation of PI3K/Akt and MEK/ERK signaling, and was attenuated by a PI3K or MEK inhibitor. The effect of adipocyte media on melanoma cells was, at least in part, due to the interaction between the adipokine leptin and its long form receptor OB-Rb, in that immunodepletion of leptin in adipocyte media or siRNA knockdown of OB-Rb in melanoma cells reversed the increase in Akt and ERK activation, enhancement in cell proliferation, and importantly, protection of melanoma cells against the drugs. In support, recombinant leptin partially recapitulated the effect of adipocyte media on melanoma cells. Of note, OB-Rb was increased on the surface of melanoma cells compared to melanocytes, whereas leptin short form receptors appeared to be suppressed post-transcriptionally, suggesting that OB-Rb was selectively upregulated in melanoma cells. Collectively, these results indicate that adipocytes contribute to the resistance of melanoma cells to chemotherapeutic drugs and agents targeting the PI3K/Akt and MEK/ERK pathways, and suggest that inhibition of the leptin/ OB-Rb system may be useful to improve the efficacy of multiple therapeutic approaches in the treatment of melanoma.

Objectives: To compare radiation doses in cone beam computed tomography (CBCT) with those of multi-detector computed tomography (MDCT) using manufacturers' standard protocols., Methods: Dose-levels in head and abdominal imaging were evaluated using a dosimetric phantom. Effective dose estimates were performed by placing thermoluminescent dosimeters in the phantom. Selected protocols for two CBCT systems and comparable protocols for one MDCT system were evaluated. Organ doses were measured and effective doses derived by applying the International Commission on Radiological Protection 2007 tissue weighting factors., Results: Effective doses estimated for the head protocol were 4.4 and 5.4 mSv for the two CBCT systems respectively and 4.3 mSv for MDCT. Eye doses for one CBCT system and MDCT were comparable (173.6 and 148.4 mGy respectively) but significantly higher compared with the second CBCT (44.6 mGy). Two abdominal protocols were evaluated for each system; the effective doses estimated were 15.0 and 18.6 mSv, 25.4 and 37.0 mSv, and 9.8 and 13.5 mSv, respectively, for each of the CBCT and MDCT systems., Conclusions: The study demonstrated comparable dose-levels for CBCT and MDCT systems in head studies, but higher dose levels for CBCT in abdominal studies. There was a significant difference in eye doses observed between the CBCT systems., Key Points: • Cone beam computed tomography (CBCT) is increasingly utilised in interventional radiology. • Effective doses for selected CBCT and MDCT protocols were estimated and compared. • Dose levels in CBCT and MDCT were comparable for head studies. • Dose levels were higher in CBCT for abdominal studies.

Background: The purpose of the present study was to determine whether intrahepatic injection of (131)I-lipiodol (Lipiodol) is effective against recurrence of surgically resected hepatocellular carcinoma (HCC)., Methods: From June 2001 through March 2007, this nationwide multi-center prospective randomized controlled trial enrolled 103 patients 4-6 weeks after curative resection of HCC with complete recovery (52: Lipiodol, 51: Control). Follow-up was every 3 months for 1 year, then every 6 months. Primary and secondary endpoints were recurrence-free survival (RFS) and overall survival (OS), respectively, both of which were evaluated by the Kaplan-Meier technique and summarized by the hazard ratio (HR). The design was based on information obtained from a similar trial that had been conducted in Hong Kong., Results: The Lipiodol group showed a small, and nonsignificant, improvement over control in RFS (HR = 0.75; 95 % confidence interval [95 % CI] 0.46-1.23; p = 0.25) and OS (HR = 0.88; 95 % CI 0.51-1.51; p = 0.64). Only two serious adverse events were reported, both with hypothyroidism caused by (131)I-lipiodol and hepatic artery dissection during angiography., Conclusions: The randomized trial provides insufficient evidence to recommend the routine use of (131)I-lipiodol in these patients.

Purpose: To compare the hepatic falciform artery (HFA) detection rates of digital subtraction angiography (DSA), computed tomography hepatic arteriography (CTHA) and 99mTc-macroaggregated albumin (99mTc-MAA) single photon emission computed tomography with integrated CT (SPECT/CT) and to correlate HFA patency with complication rates of yttrium-90 (90Y) radioembolization., Material and Methods: From August 2008 to November 2010, 79 patients (range 23-83 years, mean 62.3 years; 67 male) underwent pre-treatment DSA, CTHA and 99mTc-MAA scintigraphy (planar/SPECT/CT) to assess suitability for radioembolization with 90Y resin microspheres. Thirty-seven patients were excluded from the study, because CTHA was performed with a catheter position that did not result in opacification of the liver parenchyma adjacent to the falciform ligament. DSA, CTHA and 99mTc-MAA SPECT/CT images and medical records were retrospectively reviewed., Results: A patent HFA was detected in 22 of 42 patients (52.3%). The HFA detection rates of DSA, CTHA and 99mTc-MAA SPECT/CT were 11.9%, 52.3% and 13.3%, respectively (p<0.0001). An origin from the segment 4 artery was seen in 51.7% of HFAs. Prophylactic HFA coil-embolization prior to 90Y microspheres infusion was performed in 2 patients. Of the patients who underwent radioembolization with a patent HFA, none developed supra-umbilical radiation dermatitis. One patient experienced epigastric pain attributed to post-embolization syndrome and was managed conservatively., Conclusion: The HFA detection rate of CTHA is superior to that of DSA and 99mTc-MAA SPECT/CT. Complications related to non-target radiation of the HFA vascular territory rarely occur, even in patients undergoing radioembolization with a patent HFA., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Endoplasmic reticulum (ER) stress triggers apoptosis by activating Bim in diverse types of cells, which involves dephosphorylation of Bim(EL) by protein phosphatase 2A (PP2A). However, melanoma cells are largely resistant to ER stress-induced apoptosis, suggesting that Bim activation is suppressed in melanoma cells undergoing ER stress. We show here that ER stress reduces PP2A activity leading to increased ERK activation and subsequent phosphorylation and proteasomal degradation of Bim(EL). Despite sustained upregulation of Bim at the transcriptional level, the Bim(EL) protein expression was downregulated after an initial increase in melanoma cells subjected to pharmacological ER stress. This was mediated by increased activity of ERK, whereas the phosphatase activity of PP2A was reduced by ER stress in melanoma cells. The increase in ERK activation was, at least in part, due to reduced dephosphorylation by PP2A, which was associated with downregulation of the PP2A catalytic C subunit. Notably, instead of direct dephosphorylation of Bim(EL), PP2A inhibited its phosphorylation indirectly through dephosphorylation of ERK in melanoma cells. Taken together, these results identify downregualtion of PP2A activity as an important protective mechanism of melanoma cells against ER stress-induced apoptosis.

This study is a retrospective review of the transcervical fluoroscopy-guided fallopian tube recanalisation (FTR) procedures done in a multi-ethnic south-east Asian population, over 9 years. A total of 100 patients with infertility and documented proximal tubal obstruction (PTO) were referred for FTR. On-table hysterosalpingography under sedation demonstrated true PTO in 96 patients. At selective-salpingography, the PTO cleared in 16 patients; 78 required FTR and two had fimbrial blockage. The technical success rate of FTR was 86.8% and the post-FTR pregnancy rate was 36.84% at a mean follow-up interval of 12.2 months. There were no major, immediate procedure-related complications. There was an ectopic pregnancy in a single treated patient. Fluoroscopy-guided FTR is a safe treatment option in patients with infertility from PTO, with high technical success rate, low complication rate and increased chances of pregnancy; therefore it should be preferred before attempting more expensive and resource-intensive procedures.

The Health Sciences Authority (HSA) and the Ministry of Health (MOH) publish clinical practice guidelines on Clinical Blood Transfusion to provide doctors and patients in Singapore with evidence-based guidance for blood transfusion. This article reproduces the introduction and executive summary (with recommendations from the guidelines) from the HSA-MOH clinical practice guidelines on Clinical Blood Transfusion, for the information of readers of the Singapore Medical Journal. Chapters and page numbers mentioned in the reproduced extract refer to the full text of the guidelines, which are available from the Ministry of Health website (http://www.moh.gov.sg/mohcorp/publications.aspx?id=25700). The recommendations should be used with reference to the full text of the guidelines. Following this article are multiple choice questions based on the full text of the guidelines.

Bim is known to be critical in killing of melanoma cells by inhibition of the RAF/MEK/ERK pathway. However, the potential role of the most potent apoptosis-inducing isoform of Bim, Bim(S), remains largely unappreciated. Here, we show that inhibition of the mutant B-RAF(V600E) triggers preferential splicing to produce Bim(S), which is particularly important in induction of apoptosis in B-RAF(V600E) melanoma cells. Although the specific B-RAF(V600E) inhibitor PLX4720 upregulates all three major isoforms of Bim, Bim(EL), Bim(L), and Bim(S), at the protein and mRNA levels in B-RAF(V600E) melanoma cells, the increase in the ratios of Bim(S) mRNA to Bim(EL) and Bim(L) mRNA indicates that it favours Bim(S) splicing. Consistently, enforced expression of B-RAF(V600E) in wild-type B-RAF melanoma cells and melanocytes inhibits Bim(S) expression. The splicing factor SRp55 appears necessary for the increase in Bim(S) splicing, as SRp55 is upregulated, and its inhibition by small interfering RNA blocks induction of Bim(S) and apoptosis induced by PLX4720. The PLX4720-induced, SRp55-mediated increase in Bim(S) splicing is also mirrored in freshly isolated B-RAF(V600E) melanoma cells. These results identify a key mechanism for induction of apoptosis by PLX4720, and are instructive for sensitizing melanoma cells to B-RAF(V600E) inhibitors.

Past studies have identified a number of distinct mechanisms that contribute to the resistance of melanoma cells against apoptosis induced by TNF-related apoptosis-inducing ligand (TRAIL). In this report we show that cystatin B is another endogenous inhibitor of TRAIL-induced apoptosis. Cystatin B-deficient melanoma cell lines established by shRNA knockdown displayed increased apoptosis that was associated with enhanced activation of caspase-8 induced by TRAIL. This was not related to the inhibitory effect of cystatin B on the lysosomal cysteine proteases, cathepsin B and L, as they did not have a role in TRAIL-induced apoptosis in most melanoma cell lines even when cystatin B was inhibited. Instead, sensitization of melanoma cells to TRAIL-induced apoptosis by inhibition of cystatin B appeared associated with decreased stability of FLIP(L) as the levels of FLIP(L) were reduced because of shortened half-life time in melanoma cells deficient in cystatin B. In contrast, over-expression of cystatin B increased the levels of FLIP(L), decreased the amount of the E3 ligase Itch associated with FLIP(L), and reduced FLIP(L) ubiquitination. Inhibition of Itch by siRNA restored the levels of FLIP(L) and blocked sensitization to TRAIL-induced apoptosis associated with deficiency in cystatin B. Taken together, these results indicate that cystatin B regulates Itch-mediated degradation of FLIP(L) and thereby TRAIL-induced apoptosis in melanoma cells.

Introduction: This study aims to evaluate our experience with self-expanding nitinol stent- enabled recanalisation of long-length occlusions (30 cm or more) of the superficial femoral artery (SFA)., Methods: 573 patients underwent 842 lower limb interventions from August 2006 to December 2008. A retrospective review of patients undergoing recanalisation of long-length SFA occlusions with self-expanding nitinol stents and an evaluation of their patency and impact on limb salvage, were done., Results: 22 patients (mean age 62.5 years, male: female ratio 11:11) underwent 22 long-length SFA stenting procedures. The spectrum of critical limb ischaemia included rest pain (five), ulcer (six) and gangrene (11). Length of occlusions varied from 30 cm to 45 cm (average length 36.4 cm). Five patients had stents placed through the ipsilateral popliteal artery approach, and the rest had stents placed through the femoral artery approach. All patients were followed up over an average duration of 12 months. One patient died due to associated medical conditions during this period. Six out of 21 (28.6 percent) of the stents thrombosed completely on one year follow-up. Of these, two patients underwent amputation, one patient had a bypass, and the stent in two patients were recanalised with balloon angioplasty. All remaining patent stents showed varying degrees of stenoses at one year. The overall limb salvage rate at one year following stent placement was 81 percent., Conclusion: Our experience showed the beneficial result of long-length SFA stent placement with good limb salvage outcome. Repeat interventions may be required to maintain the patency of stents in these patients.

Introduction: Endovascular aortic repair (EVAR) has gained prominence as a means of treating aortic disease, with lower perioperative morbidity and mortality compared to open surgery. This article aimed to describe the experience of two tertiary hospitals in a Southeast Asian population., Methods: A retrospective review of 100 consecutive patients undergoing EVAR in two hospitals in Singapore was conducted. This included patients undergoing elective as well as emergency repair., Results: The mean duration of follow-up was 31.8 months. The mean aneurysm size was 6.3 cm and the mean length of stay was 12.1 days. 64 percent of the patients were of American Society of Anesthesiologists class III or above. The deployment success was 98 percent. Major complications (acute myocardial infarction, pneumonia, cerebrovascular accidents, renal failure, colonic infarction and spinal cord infarction) occurred in 18 patients. Perioperative mortality occurred in six percent of cases. The endoleak rate was 28 percent. Both patients with colonic infarction had a single patent internal iliac artery post-procedure, and end-stage renal failure., Conclusion: Our results are comparable to published experiences in aortic stenting. Our population possibly had a higher incidence of short common iliac arteries. Revascularisation of internal iliac arteries should be considered for patients with end-stage renal failure and a single patent internal iliac artery.

Aim: To review and describe the magnetic resonance imaging (MRI) features in patients with suspected placental invasion and correlate the findings with surgery and pathology findings., Materials and Methods: A retrospective review was undertaken of the MRI images of seven consecutive patients with ultrasound findings suspicious for placental invasion. Two experienced MRI radiologists, blinded to the pathology and surgery findings, reviewed the MRI. The pathology or surgical findings were used as the reference standard to establish accuracy and concordance with the MRI findings., Results: Three MRI features described in an earlier series were consistently present in the patients with placental invasion: lower uterine bulging, heterogeneous placenta, and dark intraplacental linear bands on T2-weighted images., Conclusion: MRI features, which were described in patients with placental invasion in an earlier series, were useful in establishing the presence and depth of placental invasion.

Thoracic endovascular aortic repair (TEVAR) is a recognized treatment for various diseases involving the thoracic aorta. Patients treated with TEVAR require lifelong surveillance for potential complications, with CT being highly utilized in most centres. Endoleak is the most common complication and can be detected using CT. However, other complications such as stent strut perforations and end organ ischemia can also be detected on CT. The purpose of this pictorial essay is to illustrate the CT appearance of post-TEVAR complications encountered in our institution and to highlight their significance.

Oral anticoagulants have been used widely for the treatment of venous thromboembolism and stroke prevention. The vitamin K antagonists (VKAs), such as warfarin, have been around for the last 65 years and its efficacy as thromboprophylaxis remained largely unchallenged, at least until recently. Nonetheless, the VKAs have significant limitations with marked inter- and intra-individual variability, requiring regular monitoring and have important food and drug interactions. Thus, there is an unmet need, with the quest for alternative oral anticoagulants with stable pharmacokinetics and pharmacodynamics that do not need monitoring. The novel oral anticoagulants are in 2 broad drug classes - the oral direct thrombin inhibitors and oral factor Xa inihibitors. This review article provides an overview of the pharmacology and describes the most recent published data on clinical trials with the new oral anticoagulants, which are in the more advanced stages of clinical development.

Mortality from acute liver failure (ALF) is high. Live donor liver transplantation (LDLT) is the treatment of choice for ALF in Asia, because cadaveric donors are rare. We sought to review our results in ALF patients with undergoing LDLT at our center. One hundred two LDLTs were performed at our center from April 2002 to November 2007, 15 (14%) because of ALF. Mean (SEM; median, range) follow-up was 1,065 (189; 1400; 3-2046) days. Nine patients (60%) had acute exacerbation of chronic hepatitis B; and 6 (40%) had drug-induced liver injury. Age was 47 (3; 50; 27-65) years. Ten patients (67%) were men. At transplantation, laboratory values were included bilirubin, 449 (35) micromol/L; creatinine concentration, 182 (32) mmol/L. The international normalized ratio was 2.4 (0.2). The Model for End-Stage Liver Disease (MELD) score was 34 (2). Both inpatient and long-term mortality was 20% 3 of 15 patients died. The 5-year survival was 80%. Compared with survivors, patients who died had a significantly higher creatinine concentration 289 vs 155 micromol/L, international normalized ratio (3.4 vs 2.1), MELD score (47 vs 32). We conclude that despite being sick with median and mean MELD scores of 32 and 34, 80% of patients with ALF can achieve good long-term survival after LDLT.

Living-donor liver transplantation (LDLT) is an effective treatment for patients with unresectable hepatocellular carcinoma (HCC). However, it remains controversial whether expanded listing criteria can be used for LDLT. We aimed to review results of LDLT for patients with HCC at our center. Patients with HCC were accepted for LDLT if there was no extrahepatic spread on computed tomography (CT) and positron emission tomography CT scan. Transarterial chemoembolization was performed before LDLT to control the tumors. Sirolimus or everolimus was used as part of the immunosuppressive protocol for all patients. Over the last 6 years, 35 of the 102 (34%) LDLT were performed at our center for HCC. Age (mean +/- SEM) was 55.3 +/- 1.3 years; 28 patients (80%) were men. Eight (23%) had LDLT performed in 2002 or 2003 (period 1), and 27 (77%) in 2004 to 2007 (period 2). Eleven (31%) were within and 23 (69%) were outside the Milan criteria. After 583 +/- 76 days follow-up, nine (25%) died, three of recurrent HCC. Three-year survival was significantly better in period 2 than in period 1 (90% vs 13%; P < .001). Although the 3-year survival for those within Milan criteria was better than those outside Milan criteria, the difference did not reach statistical significance (86% vs 57%; P = .26). Six (17%) had HCC recurrence, of whom five died. We concluded that reasonable medium-term survival can be obtained for patients with HCC. The experience level of the transplant team seemed to be the most important predictor of patient outcome.

Placenta accreta occurs when the placenta is abnormally adherent to the uterus, often resulting in complications in the peripartum period such as severe haemorrhage, a possible need for caesarean hysterectomy, and even severe injuries to pelvic organs. There has been a gradual shift towards conservative management of placenta accreta, involving uterine and placental conservation, with the main aim being to reduce pelvic injury and haemostasis with the aid of intervention radiology by means of insertion of occluding balloons into the internal iliac arteries. This strategy has previously been shown to reduce morbidity and mortality in carefully selected cases of placenta accreta. We review three cases of successful uterine conservation performed in our institution.

Background: There is some evidence to suggest that the standard of acute medical care provided to patients with cerebrovascular disease is a major determinant of the eventual outcome. Consequently, the Royal College of Physicians (RCP) of London issues periodic guidelines to assist healthcare providers in the management of patients presenting with stroke., Objective: An audit of the acute management of stroke in two hospitals belonging to the same health care trust in the UK., Method: Retrospective review of 98 randomly selected case-notes of patients managed for cerebrovascular disease in two acute hospitals in the UK between April and June 2004. The pertinent guidelines of RCP (London) are highlighted while audit targets were set at 70%., Results: 84% of patients presenting with cerebrovascular disease had a stroke rather than a TIA, anterior circulation strokes were commonest. All patients with stroke were admitted while those with TIAs were discharged on the same day but most patients with TIA were not followed up by Stroke specialists. Most CT-imaging of the head was done after 24 hours delaying the commencement of anti-platelets for patients with ischaemic stroke or neurosurgical referral for haemorrhagic stroke. Furthermore, there was a low rate of referral for carotid ultrasound in patients with anterior circulation strokes. Anti-platelets and statins were commenced for most patients with ischaemic stroke while diabetes was well controlled in most of them. However, ACE-inhibitors and diuretics such as indapamide were under-utilized for secondary prevention in such patients. Warfarin anti-coagulation was underutilized in patients with ischaemic stroke who had underlying chronic atrial fibrillation. While there was significant multi-disciplinary team input, dysphagia and physiotherapy assessments were delayed. Similarly, occupational therapy input and psychological assesment were omitted from the care of most patients., Conclusion: Hospital service provision for the management of cerebrovascular disease needs to provide appropriate specialist follow up for patients with TIA, prompt radiological imaging and multi-disciplinary team input for patients with stroke. Furthermore, physicians need to utilize appropriate antihypertensives and anti-coagulation more frequently in the secondary prevention of stroke.

Objectives: To evaluate the accuracy of gadolinium-enhanced magnetic resonance angiography in assessing renal artery stenosis compared to catheter digital subtraction angiography., Design: Retrospective study., Setting: Singapore General Hospital., Patients: Records of patients who underwent magnetic resonance angiography as well as digital subtraction angiography for assessment of renal artery stenosis from January 2003 to December 2005 were reviewed., Results: There were 27 patients (14 male, 13 female) with a mean age of 62 (range, 44-77) years. There were 10 patients with renal transplants; their native renal arteries were not evaluated. Each of the two experienced interventional and body magnetic resonance radiologists, who were blinded to the results, reviewed the digital subtraction angiography and magnetic resonance angiography images respectively. Digital subtraction angiography was used as the standard of reference. A total of 39 renal arteries from these 27 patients were evaluated. One of the arteries was previously stented and could not be assessed with magnetic resonance angiography due to severe artefacts. Of the remaining 38 renal arteries, two were graded as normal, seven as having mild stenosis (<50%), eight as having moderate stenosis (> or =50% but <75%), and 21 as having severe stenosis (> or =75%). Magnetic resonance angiography and digital subtraction angiography were concordant in 89% of the arteries; magnetic resonance angiography overestimated the degree of stenosis in 8% and underestimated it in 3% of them. In the evaluation of clinically significant renal artery stenosis (> or =50%) with magnetic resonance angiography, the overall sensitivity, specificity, positive predictive value, and negative predictive value were 97%, 67%, 90%, and 86% respectively. The sensitivity and specificity of magnetic resonance angiography in transplant renal artery stenosis was 100%. CONCLUSION. Our experience suggested that gadolinium-enhanced magnetic resonance angiography is a sensitive non-invasive modality useful in the assessment of clinically significant renal artery stenosis.

Pseudoangiomatous stromal hyperplasia of the breast is a benign entity characterised by dense, collagenous proliferation of mammary stroma, forming interanastomosing capillary-like spaces lined by slender spindle cells. These spaces are not true vascular spaces, hence the term "pseudoangiomatous". We report two 14-year-old girls, who presented to us with pseudoangiomatous stromal hyperplasia of the breast. We believe that our patients represent two of the youngest ethnic Chinese females to be reported with this rare condition. The development of such a rapidly enlarging lesion often leads to anxiety and concern about malignancy, and emphasises the importance in appropriate diagnosis and management. We discuss the aetiology, clinical presentation, radiological and pathological features, as well as management of this unusual condition.

This pictorial essay aims to review the literature on the management of pyogenic liver abscess, focusing on the choice of drainage. Articles on the treatment of pyogenic liver abscess, accessed through a MEDLINE search using PubMed, were reviewed. A case series of the authors' experience with clinicopathological correlation is presented to highlight the indication and outcome of each modality of drainage. Intravenous antibiotic is the first line, and mainstay, of treatment. Drainage is necessary for large abscesses, equal to or larger than 5 cm in size, to facilitate resolution. While percutaneous drainage is appropriate as first-line surgical treatment in most cases, open surgical drainage is prudent in cases of rupture, multiloculation, associated biliary or intra-abdominal pathology. Percutaneous drainage may help to optimise clinical condition prior to surgery. Laparoscopic drainage is a feasible surgical option with promising results in the future. Liver resection is reserved for concomitant localised intrahepatic disease and tumour, after control of sepsis. The final verdict on the outcome of percutaneous versus open surgical drainage of pyogenic liver abscesses requires further studies in a controlled trial setting. Nevertheless, in current good clinical practices, the choice of therapy needs to be individualised according to patient's clinical status and abscess factors. They are complementary in the management of liver abscesses.

Mycobacterium tuberculosis infection is one of the leading causes of death from communicable diseases worldwide. However, the incidence of leaking thoracic aortic tuberculous pseudoaneurysms is rare as a complication. Conventional treatment of a leaking tuberculous pseudoaneurysm involves surgery with graft interposition or patch repair. With the emergence of stent graft treatment as a viable option for leaking pseudoaneurysms, we report a 63-year-old man who had his leaking toracic aortic tuberculous pseudoaneurysm treated with endovascular stent grafting.

Introduction: Choledochal cyst is a rare benign biliary disease mostly presenting during childhood. Adult presentation is rare and associated diseases and complications are common. This paper aims to review the management of adult patients who presented to our institution with choledochal cyst, focusing on their presentation, preoperative investigations, surgical treatment given and postoperative course., Methods: A retrospective review of all our choledochal cyst patients from January 2000 to August 2004 was performed. Data collected included demographics and clinical information., Results: There were ten patients, eight female (80 percent) and two male (20 percent). The average age at presentation was 38.6 (range 16-81) years. The commonest presenting complaints were obstructive biliary disease (nine out of ten, 90 percent). There were seven Type I (70 percent), one type IVA (10 percent), one type IVB (10 percent) and one (10 percent) with Caroli's disease. Two patients had concomitant cholangiocarcinoma (20 percent). Three patients had associated cystolithiasis and one patient had pancreatitis. One patient had early cirrhosis due to her disease. Six patients underwent total cyst excision with a Roux-en-Y hepaticojejunostomy. One patient who previously had a biliary bypass underwent further resection of her cyst and Whipple's operation because of development of cholangiocarcinoma in the distal remnant cyst. They are currently well with no surgical complications. The average length of follow-up was 16 months (range six months to three years)., Conclusion: Adult patients with choledochal cyst have associated biliary problems such as the presence of cholangiocarcinoma, cystolithiasis, cholecystitis and liver cirrhosis with portal hypertension. They tend to present similar to obstructive biliary disease. The best surgical option for these patients is a total cyst excision together with a Roux-en-Y hepaticojejunostomy.

We report an unusual case of infection of a breast implant with Trichosporon spp. in an immunocompetent host. There has only been one other reported case in the published literature. The patient was a healthy 27-year-old woman who presented with pain and swelling 17 months after augmentation mammoplasty with a saline implant. Ultrasound-guided aspiration of the effusion surrounding the implant yielded Trichosporon spp. on culture. Oral therapy with fluconazole was commenced, and the implant was salvaged. The nature of this fungi, its mode of transmission and treatment are reviewed. The implications and management of implant infections are also discussed. Physicians should be aware that infection may be delayed, and cultures should be performed for aerobic and anaerobic organisms as well as acid-fast bacilli and fungi. Prompt and appropriate antimicrobial treatment may arrest the infection, sparing the patient the morbidity of a surgical drainage or implant removal.

Chronic mesenteric ischaemia is a rare disease. Patients typically present with a protracted course of vague abdominal symptoms and profound weight loss, leading to a delay in diagnosis. If untreated, it progresses to bowel infarction, which has a poor prognosis. Once diagnosed, however, it can be easily remedied via endovascular stenting or open surgery. Symptom reversal is prompt and patients rapidly achieve premorbid habitus. We report a 58-year-old man in whom the diagnosis was missed for two years, during which numerous investigations were performed. The diagnosis was eventually revealed on angiography, and he was cured by mesenteric bypass surgery. For patients with the triad of chronic, unrelenting weight loss, sitophobia (food fear) and postprandial abdominal pain, this condition must be considered, and actively sought after with angiography.

Background: Open haemorrhoidectomy is associated with considerable postoperative pain and discomfort. This study assessed whether glyceryl trinitrate (GTN) ointment promotes wound healing and reduces pain after open haemorrhoidectomy., Methods: A randomized prospective double-blind placebo-controlled trial was conducted. Patients were randomized to either 0.2 per cent GTN ointment or placebo ointment (petroleum jelly). Patients were asked to fill in a pain diary. Complete healing was defined as complete epithelialization., Results: There were 40 patients in the GTN group and 42 in the placebo group. There were no statistically significant differences in sex, weight, type of haemorrhoid, type of surgery (emergency or elective), number of haemorrhoids excised, duration of surgery, hospital stay and complication rate between the groups. Pain scores and analgesic use were not significantly different. By week 3, however, 17 patients in the GTN group had completely epithelialized wounds compared with eight patients in the placebo group (P = 0.021). Only one patient who received GTN experienced headache requiring discontinuation of the ointment., Conclusion: TGN 0.2 per cent ointment improved wound healing rates, but did not reduce pain in this study.

Portal venous gas is a well-established radiological finding in neonates. With the advancement in diagnostic imaging, more cases are being reported in adults. We present a 55-year-old man with radiological findings of both portal venous gas and pneumatosis intestinalis secondary to ischaemic necrotising enterocolitis, with subsequent fatality. The significance of finding portal venous gas and its possible aetiology is discussed.

Endoscopic treatment of bleeding duodenal varices is less invasive than the usual surgical options. However, there is limited experience with endoscopic treatment of bleeding duodenal varices, especially with that of endoscopic ligation. We report a 55-year-old man with a bleeding duodenal varix that was successfully ligated endoscopically. He has been followed up for nine months with no recurrence of bleeding. Endoscopic ligation may offer a new and effective treatment modality for bleeding duodenal varix.

Introduction: Laparoscopic adjustable gastric banding (LAGB) has been used for the treatment of obesity, being shown in western populations to be a safe and effective option. We present the results of our experience in the use of LAGB in the treatment of obesity., Methods: A retrospective review of all patients who underwent LAGB from February 1999 to June 2004 was made from a prospectively collected database. Pre-operative comorbidities, height, weight and body mass index (BMI) were recorded and compared with post-operative results. Operative times, length of stay and complications were also noted., Results: 38 consecutive patients underwent LAGB. The 16 male and 22 female patients had a mean age of 37.6 years (range 19 to 62 years) and a mean BMI of 42.7 kg per square metre (range 28.8 to 78.4 kg per square metre). Nine were done utilising the perigastric approach, and the other 29 with the pars flaccida approach. There were no open conversions. Overall peri-operative morbidity was encountered in two (5.3 percent) patients, with a minor liver laceration and a capsular splenic laceration in separate patients. There were no post-operative complications. One (2.7 percent) patient had the band removed at 29 months post-operatively on request. There were no mortalities. Mean follow-up period was 13 months (range one to 56 months). Mean BMI decreased to 40.7, 38.7, 37.4, 34.1 and 32.9 kg per square metre, respectively, at one week, one, six, 12 and 18 months post-operatively., Conclusion: LAGB is a feasible modality in the multifaceted approach to treatment of morbid obesity. The results from our follow-up are comparable to larger series in western populations, with a similar safety profile.

Introduction: Transcatheter uterine artery embolisation (UAE) for the treatment of symptomatic uterine enlargement due to fibroids has been performed in several overseas centres with promising results. We report our experience with UAE in Singapore General Hospital., Materials and Methods: Twenty women with symptomatic uterine fibroids who declined surgery were treated by transcatheter UAE. The uterine arteries were selectively catheterised and embolised with polyvinyl alcohol particles. Post-procedure analgesia was administered via a patient-controlled analgesia pump. The patients were followed up at regular intervals clinically and with transabdominal ultrasonography., Results: Transcatheter UAE was performed on all patients with no major complications. Nineteen patients had both uterine arteries embolised while 1 patient had only the right uterine artery embolised on account of hypoplasia of the left uterine artery. The mean hospital stay was 3.5 days (range, 2 to 9). At a mean follow-up of 56 weeks (range, 6 to 168), all patients reported improvements in their presenting symptoms. Objective improvement in terms of reduction of uterine and fibroid sizes was determined on ultrasonography. The median size of the uterine volume decreased from 308 to 187 mL while the median diameter of the largest fibroid reduced from 6.2 to 4.6 cm. The median haemoglobin level increased to 12.7 g/dL from the pre-procedural median of 9.9 g/dL. One patient, who initially responded with a decrease in uterine and dominant fibroid size, became symptomatic (menorrhagia) at 6 months post-embolisation. She underwent a repeat procedure with complete resolution of symptoms. A second patient had recurrence of symptoms at 12 months, but was subsequently lost to follow-up., Conclusion: Mid-term results of UAE for the treatment of symptomatic fibroids in our hospital indicate this to be a safe and effective therapeutic option.

One thousand orthopantomograms (OPGs) of patients 20-40 years old were examined. Where impacted third molars were present, the angle and depth of impaction were recorded. Results were analysed using the Pearson chi2 test. 68.6% of OPGs showed at least one impacted third molar. The frequency was three-fold higher in the mandible (1024/1079=90%) than in the maxilla (306/1077=28%), with a significantly higher frequency (P<0.05) in females (56%) than males (44%). The mesioangular impaction was the most common, and 80% of all impacted third molars were partially buried in bone. Of the 429 bilateral occurrence of impacted third molars, 423 were in the mandible. It was concluded that the frequency of impacted third molars in the Singapore Chinese population studied was generally two to three times that reported in races of the Caucasian stock. There was also double the frequency of impacted third molars when compared to a previous study in a Chinese population published in 1932 with females being more frequently affected than males.

Severe systemic sepsis after percutaneous drainage of liver abscess is rare. We report two cases of hepato-venous fistulas between hepatic abscesses and hepatic/portal veins documented on abscessography during percutaneous drainage of liver abscesses, which resulted in severe sepsis and a stormy post drainage clinical course. Liver abscesses can rupture into the portal and hepatic veins causing worsening of systemic sepsis especially when they are in close proximity to each other. During percutaneous drainage, care must also be taken to avoid overinjection of the abscess, which can worsen the fistula. The ensuing sepsis is severe and requires aggressive intensive medical care and ventilatory support to tide the patient over the septic episode.

Cerebrovascular accident (CVA) is a leading cause of death and disability in many countries. Diffusion-weighted (DW) magnetic resonance (MR) imaging has been reported to be useful in the detection of acute strokes and as an investigative tool evaluating the therapeutic effects of neuroprotective and thrombolytic agents. The objectives of this study are to share our experience using the commercially available isotropic DW scan in imaging of acute stroke, assess its usefulness over conventional T2-weighted (T2W) scans in a busy clinical radiology unit and highlight it pitfalls. We found the rapid sub-minute DW technique well suited for ill and restless stroke patients and superior to T2W scans in many ways. It was highly sensitive to acute ischaemic lesions, made lesions easily identifiable and readily differentiated the acute lesion from a background of multiple chronic infarcts. However, there are potential pitfalls in the evaluation of small hyperacute posterior fossa strokes and venous infarcts. The major strength of this MR technique lies in its ability to diagnose hyperacute strokes and thence the potential for therapeutic thrombolysis, but unfortunately patients qualifying for the "therapeutic window" were a minority. More efforts need to be focused on public education in order for this powerful imaging modality to find its true value and contribute to viability of an effective thrombolytic programme.

From January 1968 to January 1997 a series of 50 of 109 patients had undergone resection for high bile duct cancer in our institution in Rennes, France. The overall operative mortality was 12%, but there were no deaths among those who had only tumor resection or those with hepatectomy with vascular reconstruction. The early complications were biliary fistula (four cases) and subphrenic abscess (three cases), of which two of the biliary fistulas resulted in mortality. There were three gastrointestinal hemorrhages; one was due to gastritis related to hepatorenal insufficiency and was fatal. Two other deaths were due to respiratory failure and ascites associated with hepatic insufficiency. In one patient after liver transplantation with cluster resection, a biliary leak and ileocolic fistula were the cause of postoperative mortality. Another patient suffered a ruptured mycotic aneurysm after pretransplant transtumoral intubation, which emphasizes the risk of infection in an immunosuppressed patient. The main late complication was cholangitis (8 cases). This complication is most often a symptom of recurrence (four cases). Some are due to benign causes (intrahepatic lithiasis, intrahepatic foreign body granuloma). Surgical exploration is mandatory to exclude benign complications, which can then be treated palliatively. Four patients presented with recurrence but without cholangitis. In conclusion, the causes of complications after resection of high bile duct cancer should be carefully assessed to choose the correct treatment. Late cholangitis is a symptom of recurrence, but it should be explored and managed precisely.

A 29-year-old man sustained a pelvic fracture and haemorrhagic shock after a road traffic accident. He underwent an exploratory laparotomy open cystostomy, and iliac artery embolisation. Subsequent antegrade cystography and computed tomography showed a complete traumatic posterior urethral rupture with a "high riding" bladder. Delayed repair of the posterior urethra was performed 6 months later with good functional outcome. The risk of urethral injury in pelvic fractures, the mechanism of injury, and the role of imaging in the diagnosis of possible urethral injury in pelvic fractures are discussed.

Background: Laparoscopic cholecystectomy has been performed in Singapore since 1990 and, up until the end of 1997, a total of 4445 procedures had been performed in the four major teaching hospitals. Although bile duct injuries were thought to have increased following the introduction of laparoscopic cholecystectomy, there have been no reviews done on the incidence of these injuries in the Singapore context., Methods: The present retrospective review aimed to audit the rate of bile duct injuries in the four major teaching hospitals in Singapore and to document the results of management of these injuries., Results: Of the 4445 procedures performed, there were 19 (0.43%) cases of bile duct injuries. These involved the common hepatic duct (n = 8), common bile duct (n = 10), and the right hepatic duct (n = 1). The underlying gall bladder pathology included non-inflamed gall bladders (n = 10), acute cholecystitis (n = 4), Mirrizzi's syndrome (n = 3) and mucocele of the gall bladder (n = 2). Transection of the duct accounted for the majority of the injuries. Eleven bile duct injuries were identified at the time of operation. These were primarily repaired over a T tube (n = 4) or by a bilio-enteric bypass (n = 7). The remainder were diagnosed at a median of 7 days (range: 1-556 days) after surgery with a presentation of jaundice or pain. These were repaired by bilio-enteric anastomosis (n = 7) and closure over a T tube (n = 1). Three patients developed strictures subsequently, two following bilio-enteric repair after delayed diagnosis and one following immediate primary repair over a T tube. One patient developed intrahepatic stones and required a left lateral segmentectomy., Conclusions: The experience of a 0.43% bile duct injury rate is comparable to the best results from most large series in the West. Inflammation at Calot's triangle is an important associated factor for injury. Early recognition and prompt repair affords good results, and hepaticojejunostomy is recommended as the repair of choice.

Radiologists have only recently been involved in the percutaneous placement of tunnelled central venous haemodialysis catheters. We report our initial experience with our first 60 catheters. All catheters were successfully inserted. Immediate complications encountered included puncture site haemorrhage in 3 patients (5%) and puncture of the left brachiocephalic vein in 1 patient (1.7%). These were managed conservatively without any clinical sequelae. About 80% of the catheters were uncomplicated and removed electively. Slightly more than 80% of the catheters were in place for more than 30 days. Infection and blocked catheters were the most common short-term complications. Ten catheters (17%) were infected resulting in premature removal of 9. There was 1 death from presumed line sepsis. Mean duration before the onset of infection was 53 days; the rate of infection was 0.28 episodes per 100 catheter days. Five catheters (8%) were blocked or had poor flow. The mean duration before the onset of blockage was 39 days and the rate of blockage was 0.14 episodes per 100 catheter days. A higher proportion of catheters inserted from the left encountered complications. In conclusion, percutaneous insertion of tunnelled haemodialysis catheters by radiologists is safe and effective. The right internal jugular vein should be the preferred access site. Precautions should be taken to avoid infectious complications given the high rate of catheter removal amongst infected catheters.

Magnetic resonance (MR) imaging of brain metastases relies on the neovascularity of metastases and the associated breach of blood-brain barrier manifesting as enhancement on T1-weighted images. There are 2 main strategies to improve the detection of brain metastases. One may increase the dose of gadolinium and increase the signal of the lesion. Alternatively, one may also lower the signal of the background (by magnetisation transfer suppression), in which case the enhancing lesion is rendered more conspicuous without increasing the dose of gadolinium. We aim to compare the efficacy of single-dose conventional spin-echo T1 scans with magnetisation transfer (MT) suppression with triple-dose conventional spin-echo T1 scans in the detection of brain metastases in 18 patients undergoing imaging for brain metastases. An incremental dose technique was employed. After administration of a single dose of gadolinium, MT suppressed T1-weighted scans were obtained, followed by a conventional T1 scan. Two doses of gadolinium were subsequently given, achieving a cumulative triple-dose, and a conventional T1-weighted scan was then performed. We found single-dose MT suppressed and triple-dose scans performed equally well and detected 26 metastatic lesions. They detected 5 (5/26, 19%) more lesions than the conventional single-dose T1 scans. Five (5/21, 24%) questionable lesions on single-dose conventional scans were confidently diagnosed on the single-dose MT suppressed and the triple-dose conventional scan. We conclude that single-dose MT suppressed scans are a cost-effective technique of detecting brain metastases.

The detailed knowledge of the segmental anatomy of the liver has led to a rapid evolution in resectional surgery based on the intrahepatic distribution of the portal trinity (the hepatic artery, hepatic duct and portal vein). The classical intrafascial or extrahepatic approach is to isolate the appropriate branch of the portal vein, hepatic artery and the hepatic duct, outside the liver substance. Another method, the extrafascial approach, is to dissect the whole sheath of the pedicle directly after division of a substantial amount of the hepatic tissue to reach the pedicle, which is surrounded by a sheath, derived from Glisson's capsule. This Glissonian sheath encloses the portal trinity. In the transfissural or intrahepatic approach, these sheaths can be approached either anteriorly (after division of the main, right or umbilical fissure) or posteriorly from behind the porta hepatis. We describe the technique for approaching the Glissonian sheath and hence the hepatic pedicle structures and their branches by the intrahepatic posterior approach that allows early delineation of the liver segment without the need for ancillary techniques. In addition, the indications for the use of this technique in the technical and oncologic settings are also discussed.

Background: The mainstay of the management of liver abscesses has been intravenous antibiotics and radiologically guided percutaneous drainage. However, not all abscesses are treated successfully in this way, and some require surgical drainage. Laparoscopic drainage of liver abscesses may be an alternative to open surgical drainage., Methods: Twenty consecutive patients with liver abscesses treated by laparoscopic drainage in combination with intravenous antibiotics were studied prospectively. Fifteen had had failed percutaneous drainage previously., Results: There were 13 right lobe and seven left lobe abscesses ranging from 6 to 25 cm in diameter. Mean operating time was 38 min. Seventeen patients were drained successfully. Three patients developed recurrent symptoms of which two resolved with conservative measures, but one required a second laparoscopic procedure. There were no intraoperative or other postoperative complications in the 20 patients. Follow-up ranged from 5 to 12 months., Conclusions: Laparoscopic drainage of liver abscesses, in combination with systemic antibiotics, is a safe and viable alternative in all patients who require surgical drainage following failed medical or percutaneous treatment, and in those with large abscesses.

Keratoconus is a common corneal dystrophy in which penetrating keratoplasty is an effective form of treatment. A retrospective study on patients with keratoconus who underwent penetrating keratoplasty in the Singapore National Eye Centre between 1991 and 1995 was undertaken to describe and characterise the patient population and the success of this procedure. Thirty-two penetrating keratoplasties for keratoconus in 32 eyes of 29 patients were identified. Twenty eyes of 20 patients had a postoperative follow-up period of at least 12 months (range 12 to 44 months). These eyes were specifically examined for success rate and complications. Of the 32 eyes in the study, 18 (56%) belonged to Indians patients and 23 (72%) belonged to male patients. In those eyes with 12 months or more of postoperative follow-up, the visual acuity of 16 (80%) eyes improved postoperatively, with 14 (70%) eyes having a best corrected visual acuity of 6/12 or better. There were no graft failures. Nine eyes (45%) had complications postoperatively. Five eyes underwent refractive surgery for correction of astigmatism. Useful vision of 6/60 or better was achieved within 1 week postoperatively in 8 (40%) of the eyes. The authors conclude that penetrating keratoplasty is a successful procedure in keratoconic eyes not correctable by conservative therapy. The incidence of postoperative complications were however not uncommon. Although the majority of these complications were treated successfully, severe complications such as retinal detachment and glaucoma were the main causes of poor visual outcome after penetrating keratoplasty for keratoconus.

One hundred and eighty-three patients undergoing surgery were interviewed twenty-four hours following surgery to assess the quality of pain relief they received in the immediate postoperative period. Interviews were conducted using a standard questionnaire for all patients. They were asked to (1) rate the quality of pain relief they obtained on a Visual Pain Analogue Scale (VPAS-0 being no pain and 10 being the worst imaginable pain); (2) state whether they were happy and satisfied with the pain relief they received; (3) if dissatisfied, they were asked to give their reasons. 37.7% (69 patients) had moderate to severe pain--pain score greater than 6 on the VPAS. Most of these patients had undergone abdominal or major orthopaedic surgery. 32.7% (60 patients) were unhappy with their postoperative pain control. The main reasons for complaint from the patients were that analgesic injections were either not given promptly or were not given at all. The survey also highlighted the inadequate under-administration of narcotic injections in the postoperative period despite orders being written up. It showed there is an urgent need for setting up an Acute Pain Service for better postoperative pain control. An anaesthesiology based Acute Pain Service was started in October 1992.

The 'Priming principle' applied to non-depolarizing muscle relaxant atracurium was studied in 60 patients. This was a double blind study. The conditions observed for intubation were graded and the efficacy of priming dose of atracurium for shortening the onset time of intubation was studied. The patients were of ASA classification I and II and received standard premedication. The purpose of the study was to use the priming dose of atracurium to shorten the onset time of intubating dose of atracurium. This would be desirable in conditions requiring rapid intubation and in situations when the depolarizing muscle relaxant suxamethonium is contra-indicated. The results were statistically significant.