Search

Introduction: The 2005 American Association for Study of Liver Diseases (AASLD) diagnostic criteria allow non-invasive diagnosis of hepatocellular carcinoma (HCC) based on their enhancement pattern but we have observed a high incidence of atypical enhancement characteristics in HCC associated with portal vein thrombosis. This study seeks to examine the radiological features of this particular subgroup., Materials and Methods: Patients with HCC and portal vein thrombosis who underwent pre-treatment multiphasic CT imaging were drawn from a surgical database. The arterial, portal venous and delayed phase images were assessed qualitatively and quantitatively (with region of interest [ROI] analysis) for lesion hypervascularity and washout. The background enhancement of the left and right lobes of the liver was also quantifi ed by ROI analysis., Results: Twenty-fi ve lesions in 25 patients were selected for analysis. Qualitative analysis showed that 10/25 (40%) lesions demonstrated arterial hypervascularity while 16/25 (64%) lesions showed washout. Ten out of 25 (40%) lesions demonstrated both arterial hypervascularity and washout. Quantitative analysis showed that the average absolute lesion enhancement from precontrast to arterial phases was 49.1 (± 17.1) HU for hypervascular lesions compared to 23.8 (± 16.6) HU for non-hypervascular lesions (P <0.01). The mean absolute enhancement of the background liver parenchyma in the arterial phase was 13.79 (± 7.9) HU for hypervascular lesions compared to 36.6 (± 30.6) HU for non-hypervascular lesions (P = 0.03)., Conclusion: A large proportion of HCC with portal vein thrombosis lack characteristic arterial hypervascularity, which may be secondary to compensatory increased arterial supply to the background liver. This is a potential pitfall when applying imaging criteria for diagnosis of HCC.

Introduction: This study aims to determine if the quantitative method of region-of-interest (ROI) analysis of lesion attenuation on CT may be a useful adjunct to the conventional approach of diagnosis by visual assessment in assessing tracer wash-out in hepatocellular carcinomas., Materials and Methods: From a surgical database of 289 patients from 2 institutions, all patients with complete surgical, pathological and preoperative multiphasic CT scans available for review were selected. For each phase of scanning, HU readings of lesion obtained (Lesion(arterial), Lesion(PV) and Lesion(equilibrium)) were analysed using receiver operating curves (ROC) to determine the optimal method and cut-off value for quantitative assessment of tumour wash-out (Lesion(arterial - equilibrium), Lesion(PV - equilibrium) or Lesion(peak - equilibrium))., Results: Ninety-four patients with one lesion each met the inclusion criteria. The area under the curve (AUC) values for Lesion(arterial - equilibrium) (0.941) was higher than the AUC for Lesion(pv - equilibrium) (0.484) and for Lesion(peak - equilibrium) (0.667). Based on ROC analysis, a cut-off of 10HU value for Lesion(arterial - equilibrium) would yield sensitivity and specificity of 91.5% and 80.9%, respectively. ROI analysis detected 9/21 (42.9%) of lesions missed by visual analysis. Combined ROI and visual analysis yields a sensitivity of 82/94 (87.2%) compared to 73/94 (77.7%) for visual analysis alone., Conclusion: Using a cut-off of 10 HU attenuation difference between the arterial and equilibrium phases is a simple and objective method that can be included as an adjunct to visual assessment to improve sensitivity for determining lesion wash-out on CT.

Introduction: Metastatic disease to the liver in colorectal cancer is a common entity that may present synchronously or metachronously. While increasing surgical experience has improved survival outcomes, some evidence suggest that synchronous lesions should be managed differently. This review aims to update current literature on differences between the outcomes and management of synchronous and metachronous disease., Materials and Methods: Systematic review of MEDLINE database up till November 2008., Results: Discrete differences in tumour biology have been identified in separate studies. Twenty-one articles comparing outcomes were reviewed. Definitions of metachronicity varied from anytime after primary tumour evaluation to 1 year after surgery for primary tumour. Most studies reported that synchronous lesions were associated with poorer survival rates (8% to 16% reduction over 5 years). Sixteen articles comparing combined vs staged resections for synchronous tumour showed comparable morbidity and mortality. Benefits over staged resections included shorter hospital stays and earlier initiation of chemotherapy. Suitability for combined resection depended on patient age and constitution, primary tumour characteristics, size and the number of liver metastases, and the extent of liver involvement., Conclusions: Surgery remains the only treatment option that offers a chance of long-term survival for patients amenable to curative resection. Synchronicity suggests more aggressive disease although a unifying theory for biological differences explaining the disparity in tumour behaviour has not been found. Combined resection of primary tumour and synchronous metastases is a viable option pending careful patient selection and institutional experience. Given the current evidence, management of synchronous and metachronous colorectal liver metastases needs to be individualised to the needs of each patient.

Cystic neoplasm of the pancreas is a relatively uncommon condition covering a wide spectrum of pathology. The increasing incidence as a result of routine imaging tests in asymptomatic patients presents a diagnostic and therapeutic problem to the clinician. This paper discusses the role of the various investigative modalities in the management of cystic neoplasia of the pancreas.

Unlabelled: The aim of this paper was to study the efficacy, side effects and complications of radiofrequency (RF) ablation of primary and metastatic liver malignancies., Materials and Methods: We retrospectively reviewed 57 patients (39 men, 18 women; mean age, 63 years; age range, 44 to 83 years) who underwent RF ablation for liver malignancies from January 2002 to December 2004. A total of 87 tumours were ablated - 71 (81.6%) hepatocellular carcinomas and 16 (18.4%) metastases (from primaries in the colon, stomach and pancreas). RF ablation was performed either percutaneously (n = 71) under conscious sedation or intraoperatively (n = 16) under general anaesthesia. Follow-up ranged from 1 month to 41 months (mean, 15.2) and included computed tomography (CT) 1 day, 1 month and 3 months after ablation, and half-yearly thereafter. Patients were observed for local tumour progression and for the emergence of new tumours., Results: Four patients with a total of 5 tumours were lost to follow-up. Of the remaining 82 tumours treated, complete ablation was attained in 66 tumours after a single procedure, giving a primary effectiveness rate of 80.5%. Seven (8.5%) required 2 procedures to achieve complete ablation, giving a secondary effectiveness rate of 89% after 2 ablations. One tumour (1.2%) required 3 procedures to achieve complete ablation. One tumour required 4 procedures to date, with the latest follow-up CT still demonstrating incomplete ablation. Two tumours (2.4%) had an initial RF ablation and subsequent transarterial chemoembolisation (TACE). One tumour had an initial RF ablation followed by 32Phosphorus-biosilicon (BrachySil) injection, the latter as part of a Phase IIA trial. One tumour required 2 RF ablations and a subsequent TACE. Lastly, 3 tumours received initial RF ablation but subsequent local tumour progression was not treated as the patients were deemed unfit for repeat ablation. No procedure-related deaths or major complications were encountered. Minor complications were reported in 2 patients (3.8%) - subcapsular haematoma and thermal injury to the adjacent gastric antrum, both not necessitating surgical intervention., Conclusions: RF ablation is an effective, safe and relatively simple procedure for the treatment of unresectable liver malignancies.

Introduction: Acute pancreatitis appears to be less prevalent in multi-ethnic Southeast Asia, where the aetiology also appears to be influenced by ethnicity. As with acute pancreatitis elsewhere, however, pancreatic necrosis is a cause of significant mortality and the aim of this study was to review our institutional experience with pancreatic necrosectomy., Materials and Methods: The records of all patients who underwent pancreatic necrosectomy from January 2000 to December 2004 were analysed. Indications for surgery were the presence of infected necrosis, unresolving sepsis attributable to ongoing pancreatitis or the presence of gas in the pancreatic bed on imaging. Surgical debridement was achieved by debridement with closure over drains or by debridement with open packing., Results: The cohort comprised 14 of 373 patients admitted for acute pancreatitis (3.8%), with an overall mortality rate of 29%. All patients had infected necrosis with positive bacteriological cultures. Eight patients (57%) underwent debridement with closure over drains and 6 patients (43%) underwent debridement with open packing. All mortalities occurred in patients who underwent open packing, who were also associated with a higher mean Acute Physiology and Chronic Health Evaluation (APACHE) II score. The mortality rate in patients who underwent debridement less than 4 weeks after admission was 33% (2 of 6), compared with 25% (2 of 8) in patients who underwent debridement after 4 weeks. There were no mortalities in patients operated on after 6 weeks., Conclusion: Surgical debridement with closure of drains and a policy of performing delayed necrosectomy are viable in our population.

Introduction: We review the clinical applications of magnetic resonance cholangiopancreatography (MRCP) and illustrate them with clinical examples., Methods: A literature search was performed in MedLine using the keywords "MR cholangiopancreatography" and "MRCP". The relevant articles were reviewed. The radiology information system was searched for MRCP examinations performed from July 1999 to December 2002. A surgical database of resected cases was also referenced. Illustrative cases were chosen in consultation with surgical authors to show the clinical applications of MRCP., Results: MRCP is useful for assessment of choledocholithiasis, choledochal cysts, pancreas divisum, primary sclerosing cholangitis, pancreatitis and anatomical variation of the biliary ducts. When complemented with dynamic gadolinium-enhanced studies, MRCP is useful for assessment of ductal cholangiocarcinoma, pancreatic and gall bladder neoplasms. Illustrative cases are provided., Conclusion: MRCP is an important modality for the clinical assessment of biliary and pancreatic disorders.

Introduction: We compare the breath-hold fast recovery fast spin echo (BHFRFSE) T2-weighted and non-breath-hold fast spin echo (NBHFSE) T2-weighted sequences in image quality and lesion characterisation of focal liver lesions., Materials and Methods: Fat-suppressed T2-weighted magnetic resonance (MR) images obtained with the 2 sequences (BHFRFSE and NBHFSE) in 79 patients with 113 liver lesions were analysed retrospectively. The image quality and nature of the lesions were evaluated by 2 experienced radiologists., Results: Based on receiver operating characteristic curve analysis, lesion characterisation was comparable for both sequences. The image quality of BHFRFSE was significantly better than that of NBHFSE. The NBHFSE missed 4 malignant lesions while BHFRFSE missed 2 malignant lesions., Conclusion: BHFRFSE performs similarly to NBHFSE in image quality and liver lesion characterisation.

Introduction: This article reviews the various computed tomography (CT) appearances of hepatic metastases from colorectal primaries and assesses the frequency of occurrence of the various patterns., Materials and Methods: This is a retrospective study of the CT appearances of histologically proven colorectal hepatic metastases in a group of 52 patients who had undergone surgical hepatic resection between January 1994 and December 2001. A total of 74 hepatic metastatic lesions were reviewed. All lesions were examined in the portal venous phase., Results: A discernible rim was seen in 54 lesions (73%). Thick rim was present in 36 lesions (48.6%) and thin rim in 18 lesions (24.3%). Enhancement of the rim was present in 62 cases (83.8%). Increased central attenuation was seen in 38 lesions (51.4%). Of these, the centre was heterogeneous in 76.3% and scar-like in 23.7%. A non-enhancing rim was seen in 12 lesions (16.2%) which appeared as lesions with "bevelled edge". Thick enhancing rim with non-enhancing centre was the most common combination in 15 lesions (20.3%)., Conclusion: An enhancing rim could be seen in 83.8% of lesions. Increased central attenuation was present in 51.4% of the lesions. Familiarity with the various CT appearances may facilitate identification and diagnosis of colorectal liver metastases.

Objective: To review and evaluate trends for short and long-term outcomes of patients who have undergone liver resection for colorectal metastases in a single institution over a period of 7 years., Materials and Methods: A retrospective review and analysis of clinicopathologic data and outcome of potentially curative liver resection for colorectal metastases in a series of 96 patients from January 1994 to December 2001 was done. Data were statistically analysed. Perioperative mortality, morbidity, overall survival and disease-free survival rates were reported., Results: A total of 96 patients underwent potentially curative liver resection for colorectal metastases. There were 64 males (66.7%) and 32 females (33.3%) with a median age of 60 years. There was no perioperative mortality. Postoperative morbidity was 7.2%. The median length of follow-up for the entire cohort of post hepatic resection was 29 months with 1-year and 3-year overall survival rates of 99% and 71%, respectively. The disease-free survival rates were 76% and 48%, respectively. Minor resections for the liver metastases showed significantly better overall survival. Primary tumour in the colon compared to rectum, disease-free interval (DFI) < 12 months and adjuvant chemotherapy showed a trend towards shorter overall survival. Carcinoembryonic antigen (CEA) levels greater than 100 ng/mL significantly shortens the disease-free survival., Conclusion: Liver resection for colorectal metastases in our institution is a safe and effective treatment option in properly selected patients, which currently represents the best chance for long-term survival and possibly "cure".

Introduction: In patients with adult polycystic liver disease (APLD), there is considerable debate surrounding the most effective way of managing symptomatic cysts. Conservative approaches like percutaneous aspiration or cyst fenestration are associated with low morbidity but high recurrence rates. Conversely, liver resection and hepatectomy with orthotopic liver transplantation is drastic and associated with high morbidity and mortality rates. Our aim is to review the current understanding of liver cystogenesis in these patients and the therapeutic options available in order to provide a rationale guide to management of this intriguing condition., Methods: This article summarises the findings of published papers in major international journals indexed on MEDLINE on APLD using the key words--adult polycystic liver disease, liver cysts, fenestration, liver resection, liver transplantation and polycystic kidney disease. The period of search includes papers between 1965 and 2000., Results: Published studies have suggested a 'two-hit' hypothesis to explain the development of liver cysts in patients with APLD. This will provide the rationale for future management. Meanwhile, the indications, pitfalls and results of the various therapeutic options are reviewed. Management of symptoms has to be tailored to the underlying severity of the liver cystic disease, co-morbidity and procedural risks and recurrence rates., Conclusion: Good long-term relief of symptoms can be achieved with the correct procedure at acceptable morbidity and mortality rates. We have provided guidelines on the various options available to enable a structured approach to the management of APLD.

The recognition of hepatic stellate cells (HSC) around and within hepatocellular carcinoma (HCC) in human livers has generated interest in the interactions between HSC and HCC. We explored the possibility of creating an animal model to allow in vivo investigations of this interaction. Eighteen adult Buffalo rats were inoculated with 1 x 10(6) cells obtained from cultures of Morris 7777 hepatoma cell line (ATCC). The rats were sacrificed at 2-, 3-, and 4-week intervals. Identification of activated HSC was with immunohistochemistry for alpha-smooth muscle actin (alpha-SMA). There was 100% survival of all animals until sacrifice. Tumour formation occurred in 94.4% of rats, and was of a good size by two weeks. Expression of alpha-SMA was observed around and within all HCC, but absent from normal tissue, and this showed colocalisation with collagen deposition. These findings are consistent with those previously reported in resected HCC in humans. The high survival, good tumour yield, consistent generation of activated HSC around the tumours, and similarities in histological appearance to the human HSC-HCC distribution pattern, make this a reliable animal model for in vivo studies on HSC-HCC interaction.

Training in laparoscopic surgery started with short two to three-day courses, frequently unstructured and unaccredited, in a rush to provide surgeons with supposedly adequate training in laparoscopic techniques before performing laparoscopic cholecystectomy in patients. The high incidence of complications with this situation led to guidelines on training, credentialling and auditing being drawn up by several responsible professional bodies. Almost a decade after the introduction of laparoscopic cholecystectomy, the situation with training in laparoscopic surgery is still unresolved in many countries. This article reviews the current opinion on training in laparoscopic surgery, and presents the various teaching models and techniques employed to facilitate this process. Training in laparoscopic surgery should form part of the general surgery training programme, and should involve a combination of short introductory courses with hands-on animal models, and a period of preceptorship following this.

Laparoscopic cholecystectomy was introduced into Singapore in 1990, and has since replaced conventional cholecystectomy as the treatment of choice for gallstone disease in most situations. In contrast, laparoscopic hernia repair introduced two years later in the same wave of enthusiasm, was received with scepticism and much less acceptance. A survey of 27 general surgeons in three large institutions in Singapore was performed to analyse this observation. The majority of surgeons felt that laparoscopic hernia repair (i) had limited applications, mainly for bilateral and recurrent hernias, (ii) was not completely established as a technique, requiring refinement in the procedure, (iii) was costly, and (iv) did not have objective evidence of long-term benefits over conventional hernia repair.

Kimura's disease is an uncommon chronic inflammatory process of obscure origin. It is more common among Orientals and affects particularly the young male. Sites of predilection include the head and neck region, primarily the subcutaneous tissue and dermis. Unusual sites of occurrence that have been reported include the kidney, the orbit, the ear and the spermatic cord. Kimura's disease involving a major nerve bundle has not been described, and we report here the findings of a case of histologically proven Kimura's disease of the median nerve occurring in a 21-year-old Chinese girl. Typical diagnostic histological features of Kimura's disease in contrast to angiolymphoid hyperplasia, and the treatment options for Kimura's disease are also described.

Thoracoscopic vagotomy is a well-established technique in the management of recurrent peptic ulceration after previous abdominal vagotomy. The procedure allows an easy approach to the vagus nerves without having to dissect through dense adhesions from previous surgery. With thoracic vagotomy, the main morbidity is postoperative pain from the thoracotomy incision and rib spreading. Advances in endoscopic camera systems and instrumentation allow thoracic vagotomy to be safely and effectively accomplished by thoracoscopic surgery techniques, with reduced postoperative pain. We describe our experiences with thoracoscopic vagotomy in two cases of recurrent peptic ulceration.

A benign thyroglossal cyst is a common clinical condition and is second only to a cervical lymph node as the most common cause of a solitary neck swelling. Primary carcinoma of a thyroglossal cyst, however, is rare and has been described in only 115 cases in the literature. The malignant cysts are clinically difficult to differentiate from benign lesions and the diagnosis often rests on histopathological examination. Before initiating treatment, primary papillary carcinoma of the thyroid gland must be excluded. The treatment options range from simple excision to a Sistrunk operation with concurrent cervical lymph node dissection. We describe here a case of papillary carcinoma of a thyroglossal cyst and review the 115 reported cases.

Papillary carcinoma of the thyroid has a propensity for spread to the regional lymph nodes, in particular those along the recurrent laryngeal nerve. Twenty cases of papillary carcinoma of the thyroid had prophylactic clearance of the lymph nodes along the tracheo-oesophageal groove, and one patient had removal of recurrent disease in the groove. Eleven of the twenty patients had, in addition, some form of cervical lymph node clearance for clinically palpable ipsilateral cervical lymph nodes. Metastases to the tracheo-oesophageal groove lymph nodes was seen in seven of the twenty patients (35%). Tumour size, age, sex, race and cervical lymph node involvement did not appear to predict involvement of the tracheo-oesophageal groove lymph nodes. Clearance of the lymph nodes along the tracheo-oesophageal groove at the time of resection of primary disease is worthwhile for thyroid papillary carcinoma, because of the high incidence rate (35%) and also clearance for subsequent recurrence will be more difficult with a higher risk of damage to the recurrent laryngeal nerve and parathyroids.

Calcifying epithelioma of Malherbe (pilomatrixoma) is a relatively uncommon benign skin tumour of hair follicle origin. It usually presents in the face and upper extremities of young adults as an asymptomatic subcutaneous or dermal tumour. Treatment is surgical excision. This paper presents a case of a large tumour in the preauricular region with difficulty in diagnosis preoperatively and required a superficial parotidectomy to clear the tumour from the facial nerve.

B-mode real-time ultrasound was used to assess vocal cord function in six patients with recurrent laryngeal nerve palsy. The thyroid cartilage acted as an acoustic window through which the true cords appear as hypoechoic structures. Vocal cord palsy detected on ultrasound was compared with fibreoptic direct laryngoscopy and indirect laryngoscopy mirror examination. Good correlation was seen in all the cases.

Adrenal cysts are a rare entity. Only about 300 cases have been reported throughout the world. A case of an asymptomatic, benign, non-functioning adrenal cyst of the left adrenal gland is presented. Pre-operative diagnosis is usually by incidental imaging findings as the majority of adrenal cysts are asymptomatic. The adrenal cyst in this case was detected on an abdominal ultrasound for the investigation of jaundice, and confirmed by a CT scan examination. Selective biochemical studies are needed to assess adrenal function, and here they were normal. Simple surgical enucleation of the cyst, with preservation of remaining adrenal tissue is the treatment of choice.

Retroperitoneal neurilemmomas are the rarest of all retroperitoneal tumours. A rare case of a very large benign retroperitoneal neurilemmoma is presented. Pre-operative diagnosis of these tumours is difficult and the majority are asymptomatic. They are usually detected as an abdominal mass on routine examination as in this case. Despite severe displacement and distortion of the inferior vena cava in this patient, there were no clinical abnormalities detected. The predominantly cystic nature of the tumour was well demonstrated by ultrasound and CT scan examination but the true nature of the tumour could not be diagnosed. It is very rare for these tumours to be malignant and recurrence after surgical excision is rare.