Clinical outcome of open and laparoscopic surgery in Dukes' B and C rectal cancer: experience from a regional hospital in Hong Kong.

OBJECTIVE: To compare the long-term outcome of open and laparoscopic surgery for Dukes' B and C rectal cancer in a regional hospital in Hong Kong. DESIGN: Retrospective study. SETTING: A regional hospital in Hong Kong. MAIN OUTCOME MEASURES: Survival and local recurrence rates. PATIENTS: Patients with Dukes' B and C rectal cancers underwent elective curative open or laparoscopic surgery during the period December 2000 to December 2006. RESULTS: A total of 222 patients (open surgery, n=133; laparoscopic surgery, n=89) were assessed. The overall 3- and 5-year survival rates for all patients were 72% and 58%, respectively. Local recurrence rates were similar in both groups. Laparoscopic group had better overall survival (P=0.014), however. The overall 3-year survival rates were 79% and 68% in the laparoscopic and open groups, respectively. The corresponding 5-year rates were 75% and 52%. Multivariate analysis also demonstrated that laparoscopic surgery was a significant independent factor for better survival. Chemotherapy, local recurrence, lymph node metastasis, and poorly differentiated tumour were significantly associated with survival. CONCLUSION: Laparoscopic surgery for Dukes' B and C rectal cancer was associated with more favourable survival than with open surgery.

Replication study of SNP associations for colorectal cancer in Hong Kong Chinese.

BACKGROUND: Recent genome-wide association studies of colorectal cancer (CRC) have identified common single-nucleotide polymorphisms (SNPs) mapping to 10 independent loci that confer modest increased risk. These studies have been conducted in European populations and it is unclear whether these observations generalise to populations with different ethnicities and rates of CRC. METHODS: An association study was performed on 892 CRC cases and 890 controls recruited from the Hong Kong Chinese population, genotyping 32 SNPs, which were either associated with CRC in previous studies or are in close proximity to previously reported risk SNPs. RESULTS: Twelve of the SNPs showed evidence of an association. The strongest associations were provided by rs10795668 on 10p14, rs4779584 on 15q14 and rs12953717 on 18q21.2. There was significant linear association between CRC risk and the number of independent risk variants possessed by an individual (P=2.29 × 10(-5)). CONCLUSION: These results indicate that some previously reported SNP associations also impact on CRC risk in the Chinese population. Possible reasons for failure of replication for some loci include inadequate study power, differences in allele frequency, linkage disequilibrium structure or effect size between populations. Our results suggest that many associations for CRC are likely to generalise across populations.

Arachnoiditis ossificans.

Arachnoiditis ossificans is a rare type of chronic arachnoiditis characterised by the presence of calcification or ossification of the spinal arachnoid. There are a few reports of this condition in Japanese and western populations but no case has been reported in a Chinese population before. We describe a 35-year-old woman with typical findings of arachnoiditis ossificans. A brief review of the literature is also presented.

Spinal infection caused by Mycobacterium avium complex in a patient with no acquired immune deficiency syndrome: a case report.

Spinal infection caused by Mycobacterium avium complex (MAC) is rarely seen in people who do not have acquired immune deficiency syndrome. We report such a case in a 60-year-old man who underwent anterior spinal fusion after treatment with antibiotics had failed. The presentation of MAC spinal infection is different from that seen in MAC lung infection, with more than half presenting with urgent or semi-urgent neurological deficits. Younger patients who are not immunocompromised can also be infected. It should be considered as a differential diagnosis in patients with tuberculosis of the spine. The use of antibiotics should be based on the cultured organism's sensitivity results. Indications for surgery are progressive bony destruction, abscess formation, and neurological compression.

Spontaneous spinal epidural haematoma in a 15-month-old boy presenting with a wry neck: a case report.

A 15-month-old boy presented with a 2-day history of a wry neck (bent to the left side) with no definite trauma. He had bilateral upper limb weakness and was afebrile, conscious, and stable. There was no spontaneous movement in both upper limbs. Magnetic resonance imaging of the cervical and thoracic spine demonstrated an extensive spontaneous spinal epidural haematoma from C3 to T8. 23 hours after admission, the patient underwent an emergency right-sided C3 to T8 hemi-laminectomy and haematoma evacuation. The patent's strength gradually recovered and he attained full power 3 weeks after operation. Spontaneous spinal epidural haematoma is a rare disease in children. A high index of suspicion is essential for its effective management as the interval to operation is the most important prognostic factor.

Using block-based multiparameter representation to detect tumor features on T2-weighted brain MRI images.

OBJECTIVE: The objective of this paper is to present an analytical method for digitized images to detect tumors or lesions in a medical decision support system. METHOD: The authors have developed a simple method of tumor detection using three parameter values: edge (E), gray (G), and contrast (H). The method proposed here first studied the VHD (Visible Human Dataset) input brain feature using EGH parameters that divided the input image into fixed-size blocks (templates). The EGH parameters for the feature blocks were calculated and parameterized to detect the occurrences of abnormalities. These abnormal blocks were then marked for interpretation. RESULTS: Measurements of the following medical dataset were performed: 1) different time-interval images from the same dataset, 2) different brain disease images from multiple datasets, and 3) multiple slice images from multiple datasets. Our experimental results illustrate the ability of our proposed technique to detect tumor blocks with conceptual simplicity and computational efficiency. CONCLUSION: In this paper, we present output examples from our prototype system, comparing detection accuracy and system performance.

Efficacy of multidisciplinary approach in treatment of constipation: a pilot study.

OBJECTIVE: To evaluate a multidisciplinary Hong Kong treatment programme for patients with constipation. DESIGN: Pilot study. SETTING: A joint collaboration among the departments of surgery, physiotherapy, and dietetics in a regional hospital in Hong Kong. PATIENTS: Thirty-one constipated patients with normal colonic transit and pelvic floor dyssynergia. INTERVENTION: Multidisciplinary treatment including dietary modification, bowel habit adjustment, and physiotherapy. MAIN OUTCOME MEASURES: Anorectal manometry, fibre intake, subjective improvement, bowel frequency, Bristol score, and straining time and effort. RESULTS: Significant improvement was found in mean fibre intake, straining time and effort, but not in anal manometric results. A total of 78% of patients demonstrated more than 50% improvement in subjective symptoms, whereas 70% of the patients enjoyed objective improvement in pelvic floor dyssynergia documented by electromyography and anal pressure during a push effort. CONCLUSION: The multidisciplinary rehabilitative programme for constipated patients significantly improved symptoms. Electromyography and anal pressure during a push effort are useful tools for objective assessment of the treatment effect.

Fusion rate of anterior cervical plating after corpectomy.

PURPOSE: To evaluate the neurological recovery and fusion rate of patients with myelopathy who were treated with anterior corpectomy and anterior cervical plating. METHODS: The results of 17 cervical myelopathy patients who underwent decompression and anterior cervical plating were retrospectively reviewed at a mean follow-up of 2 years. RESULTS: By Kurokawa score, 82.4% of patients showed excellent-to-good results. The fusion rates of 2-level and 3-level anterior cervical corpectomy, and of anterior plate fixation were 100%. There were no implant- or graft-related complications. Transient dysphagia in 9 (52.9%) patients resolved after a mean of 3 months (range, 1-9 months). CONCLUSION: The use of anterior cervical plating after anterior corpectomy and fusion with autologous bone graft greatly enhances arthrodesis. The improved fusion rate and low complication rate associated with anterior cervical plating may justify its use in the treatment of cervical spondylotic myelopathy.

Fractures associated with non-accidental injury--an orthopaedic perspective in a local regional hospital.

OBJECTIVES: To identify the potential risk factors for fractures due to non-accidental injury in children, and to alert clinicians and health care workers to the diagnosis of child abuse. DESIGN: Retrospective review. SETTING: Regional hospital, Hong Kong. PATIENTS: Children who were admitted to the hospital with a clinical diagnosis of child abuse with associated fracture(s) between January 1996 and April 2004. MAIN OUTCOME MEASURES: Demographic data, site of fractures, and investigations performed. RESULTS: Of the 377 children presented with non-accidental injuries, 29 (15 male, 14 female) had bone fractures. The mean age of the 29 children at the time of injury was 5 years and 5 months. Of the nine records showing pregnancy, seven were unplanned. Approximately 75% of the families were living in public housing estates, and 28% were receiving social security subsidy. Over half (52%) of the abused children were aged 3 years or less. A total of 78 fractures were documented with a mean of 2.7 fractures per child. The most common sites of fracture were the forearm (29%), followed by the ribs (24%). Most long bone fractures occurred in those aged 3 years or less. Fractures were detected by skeletal survey and bone scan for 90% of the children. CONCLUSION: A number of potential risk factors were identified in children with fractures associated with non-accidental injury. They included age younger than 3 years, lower socio-economic status, presentation with long bone fracture, and unplanned pregnancy. Bone scan and skeletal survey are mutually complementary, and both should be performed in cases of suspected child abuse. Subsequent management requires cooperation of multi-disciplinary health care professionals.

The management of superior dislocation of the patella with interlocking osteophytes--an update on a rare problem.

The superior dislocation of the patella with interlocking osteophytes is a rare condition. A review of the English literature revealed only 12 reported cases. The purpose of reviewing these case reports is to highlight the unusual presentation and the injury mechanism in 2 of our patients, and to present our treatment algorithm. Closed reduction with manipulation of the patella, with or without anaesthesia, was performed without difficulty. We recommend an intermediate step of trying a regional nerve block before proceeding to general anaesthesia. Our patients had full range-of-motion after reduction and they were symptom-free after 3 years of follow-up. There were no recurrent dislocations in our patients.

Stapled haemorrhoidectomy in Chinese patients: a prospective randomised control study.

OBJECTIVE: To compare stapled haemorrhoidectomy with open diathermy haemorrhoidectomy in Chinese patients with respect to the postoperative pain, symptom control, and manometric alterations. DESIGN: Prospective randomised controlled trial. SETTING: A regional general surgical unit, Hong Kong. PATIENTS: Twenty-four patients with second- or third-degree haemorrhoids or who have had failed medical treatment. INTERVENTION: Open diathermy haemorrhoidectomy or stapled haemorrhoidectomy. MAIN OUTCOME MEASURES: Structured questionnaire for symptoms, anorectal manometry, transrectal ultrasound, and postoperative pain. RESULTS: Stapled haemorrhoidectomy compared with open diathermy haemorrhoidectomy resulted in similar postoperative pain and drug requirements. Postoperative control of prolapse symptoms was significantly better with open diathermy haemorrhoidectomy than with stapled. The control of other symptoms was similar with regard to bleeding, pain, pruritus, and incontinence scores. Anorectal manometry showed a decrease in the maximum resting pressure and maximum squeeze pressure in both groups, but the decrease was only significant in the stapled haemorrhoidectomy group. CONCLUSIONS: Stapled haemorrhoidectomy is as effective as conventional haemorrhoidectomy for the treatment of haemorrhoids, but with the exception of skin tag prolapse. There is a need for long-term follow-up for the changes in manometric parameters after haemorrhoidectomy.

Microbial contamination of femoral head allografts.

OBJECTIVE: To study the incidence of microbial contamination at the bone bank of the United Christian Hospital. DESIGN. Retrospective study. SETTING: Regional hospital, Hong Kong. PATIENTS: A total of 151 patients (33 men and 118 women) who underwent hip arthroplasty surgery and from whom femoral head allografts were retrieved between January 1994 and March 2000; and 81 patients in whom allografts were implanted. MAIN OUTCOME MEASURES: Bone biopsies were taken from the femoral head and used to detect any microbial contamination that might have occurred during removal and after storage. The rates of infection among recipients and donors were also assessed. RESULTS: Of the 151 allografts, 94 non-contaminated allografts were implanted by the end of the study. Fourteen (9.3%) heads showed positive culture results after retrieval and were discarded. Four (4.3%) of the 94 stored allografts that were implanted tested positive for microbial growth, but the recipients of these allografts did not develop any clinical infection. Three (3.2%) had wound infections after implantation of the stored allografts although the grafts had previously been tested negative for any microbial contamination. CONCLUSION: Our centre has a low allograft contamination rate. The wound infection rate among recipients was also low. The culture of a bone biopsy sample is a reliable method to detect contamination of bone grafts. However, the contamination rate among stored allografts should prompt orthopaedics departments to review allograft handling procedures, so as to minimise the chance of contamination.

Treatment of early rectal tumours by transanal endoscopic microsurgery in Hong Kong: prospective study.

OBJECTIVE: To summarise the results of transanal endoscopic microsurgery for the treatment of rectal villous adenoma and early rectal tumours. DESIGN: Prospective study. SETTING: Regional hospital, Hong Kong. PATIENTS: Consecutive patients between November 1995 and January 2003. INTERVENTION: Transanal endoscopic microsurgery. MAIN OUTCOME MEASURES: Intra-operative morbidity and mortality, complication rate, operating time, postoperative morbidity and mortality, recurrence rate and correlation between preoperative ultrasonography staging and postoperative pathological staging. RESULTS: Thirty-two patients with rectal villous adenoma and early rectal carcinoma were registered, 31 of whom (14 men and 17 women) were included in the study. The median tumour size was 2.5 (range, 1-8) cm and the median operating time was 95 (45-220) minutes. The median follow-up period was 23 (2-92) months, and there was no local recurrence. There was no operation-related mortality and the resection margins were all clear. Complications included temporary flatus incontinence (n=2), acute retention of urine (n=1), exacerbation of chronic obstructive airway disease (n=1), and secondary haemorrhage in a patient on aspirin. CONCLUSIONS: Transanal endoscopic microsurgery is a safe procedure and can achieve good local tumour control. It is ideal in the management of rectal villous adenomas at stages pT0 and pTis. Its application is now extended to the treatment of early rectal carcinoma at stage pT1 with curative intent. For tumours at stage pT2 or later, it can also serve as a good option for local palliation.

Aggressive thoracic actinomycosis complicated by vertebral osteomyelitis and epidural abscess leading to spinal cord compression.

STUDY DESIGN: Report of a successfully diagnosed and treated case of spinal cord compression due to epidural actinomycosis. OBJECTIVE: To illustrate that proper use of imaging strategy can greatly facilitate diagnosis and management of this rare condition. SUMMARY OF BACKGROUND DATA: Spinal actinomycosis causing epidural abscess and significant spinal cord compression is an uncommon condition. Although diagnosis is difficult, favorable results are widely reported when specific therapy is instituted. METHODS: A 32-year-old Chinese man had extensive dorsal thoracic soft tissue swelling and lower limb weakness. Collapse of the T5 vertebral body was found on plain radiographs with mediastinal infiltrates on chest radiograph. It took magnetic resonance imaging (MRI) to fully delineate the epidural abscess and dorsal muscular abscesses, which were not depicted by computed tomographic (CT) scan. Diagnosis was made by examination of CT-guided aspirate and tissue recovered during surgery by a microbiologist. The patient received high-dose intravenous penicillin and prompt spinal decompression once diagnosis of actinomycosis was confirmed. RESULTS: The dorsal muscular abscesses and upper thoracic epidural abscess resolved rapidly after intravenous antibiotics and surgical drainage. This was well documented by follow-up MRI and the full recovery of motor power and lower limb sensation in the patient. CONCLUSIONS: High clinical suspicion and proper use of imaging data led to timely diagnosis of this rare case of mediastinal, epidural, and intramuscular thoracic actinomycosis. Specific antibiotic therapy and timely, well-targeted surgical intervention greatly improve the outcome of this condition.

Effects of order of magnesium exposure on the postantibiotic effect and bactericidal activity of ciprofloxacin.

Quinolone antibiotics are known to form chelates with various metal cations. It has also been recognized that the physicochemical properties of the chelated antibiotic differ significantly from its unchelated form, thereby causing a reduction in antimicrobial activity. In addition, the formation of metal chelates is also believed to be the reason for the significant reduction in oral bioavailability for the quinolones when concomitantly dosed with oral cation containing agents. This has prompted the adoption of an alternate dosing regimen by introducing an adequate interval between the two. As a result of this dosing strategy, pathogens are exposed to the quinolones and metal cations in alternate orders. Using magnesium, ciprofloxacin, and Escherichia coli as the test organism, investigations were conducted to study the changes in bactericidal activity and postantibiotic effect (PAE) in relation to the orders of cation/antibiotic exposure. Results showed a parallel decrease in both bactericidal activity and PAE when the test organism was exposed to the two agents simultaneously; however, no apparent influences on these two antimicrobial effects were observed when Mg2+ was presented before or after ciprofloxacin exposure. In line with the current dosing recommendations, the interval spaced between ciprofloxacin and Mg2+ should preserve both the bactericidal activity and PAE exhibited by the antibiotic. How the present data are to be extrapolated to other quinolones and cations should be the subject of future studies.

The potential impact of breast cancer screening in Hong Kong.

BACKGROUND: Breast cancer is the second most common cancer and cause of death in women from Hong Kong. The Well Women Clinic at Kwong Wah Hospital offers breast cancer screening (physical examination and mammography) for women over 40 years of age. METHODS: Results of screening over a 2-year period revealed an overall malignancy detection rate of 2.6 per 1000 screens with a strong selection bias for symptomatic women. RESULTS: Screening only slightly increased the proportion of stage I cancers detected; of the malignancies detected, a significant percentage were in situ cancers with doubtful effects on breast cancer mortality. Teamwork and communication were useful in keeping a low referral rate to the surgical clinic of 6.1%, as well as a low biopsy rate for mammographic abnormalities. CONCLUSIONS: A re-evaluation of the real risk of breast cancer in young women together with the lack of proven value from screening has suggested a need for reconsideration of offering screening to women 40 years and over in Hong Kong.

The reproducibility of cephalometric landmarks: an experimental study on skulls.

Few previous cephalometric studies have used dry skulls in order to eliminate the effects of the facial soft tissues. The aim of this study were to quantify the intra-examiner reproducibility of the commonly used cephalometric landmarks, angles and distances, using dry skulls and to compare these errors with previous error data obtained from normal cephalograms of living patients. Thirty skulls were mounted in a purpose-designed holder and repeat cephalograms of each skull were recorded and digitised. All measurements were made relative to an X-Y coordinate reference grid. Scattergrams were produced to show the characteristic distribution of the intra-examiner reproducibility errors for the landmarks, and the reproducibility of the angles and distances were tabulated. This data was compared with a related study that included the soft tissue profile. The standard deviations of the skeletal and dental angles and distances were greater in the presence of the soft tissues. These differences were up to four times larger for measurements including the location of Nasion (e.g. SNA, SNB and SNPg), which was the landmark location most affected by the presence of soft tissues, and for the distance: Incisal tip of Lower Incisor to Pogonion. Anterior Nasal Spine, in the horizontal plane, was also greatly affected by the presence of the soft tissues. By using dry skulls, the errors observed in this study may serve as standards for the rational interpretation of clinical cephalometric values.