bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of the Arg345Trp disease‐associated allele of the EFEMP1 gene in individuals with early onset drusen or familial age‐related macular degeneration
Authors: Guymer Robyn H , McNeil Robyn , Cain Melinda , Tomlin Belinda , Allen Penelope J , Dip Chi Luu , Baird Paul N
Published: March 2003

Background: A single base change within the EFEMP1 gene has been associated with malattia leventinese and Doyne honeycomb retinal dystrophy, two dominantly inherited macular diseases with early onset drusen. The aim of this study was to determine whether the same disease allele was also associated with other forms of early onset drusen or familial cases of age‐related macular degeneration.

Methods: Thirteen index cases of early onset drusen together with 15 other family members were examined. In addition, 54 familial cases of age‐related macular degeneration were examined. Blood was taken for DNA analysis and screened for the Arg345Trp disease‐associated allele of the EFEMP1 gene. Twenty‐four cases of malattia leventinese or Doyne honeycomb retinal dystrophy were also screened as positive controls. Another 150 ethnicity‐ and age‐matched individuals acted as controls.

Results: The Arg345Trp disease‐associated allele in the EFEMP1 gene was confirmed in individuals with malattia leventinese and Doyne honeycomb retinal dystrophy. However, involvement of this allele was not evident in either early onset drusen or familial age‐related macular degeneration.

Conclusions: The Arg345Trp disease‐associated allele of the EFEMP1 gene does not appear to be associated with cases of early onset drusen that fall outside the diagnosis of malattia leventinese or Doyne honeycomb retinal dys­trophy, nor does it appear to play a role in familial age‐related macular degeneration. These findings do not exclude the involvement of other alleles of the EFEMP1 gene in either phenotype. The genetic mechanisms involved in the hetero­geneous group of early onset drusen remain to be elucidated but should lead to insights into the genetic causes of macular diseases.
Penetration of oral and topical ciprofloxacin into the aqueous humour
Authors: Ghazi‐Nouri Seyed M , Lochhead Jonathan , Mearza Ali A , Qureshi Muhammad A , Thompson Graham M , Cowdrey Geoff , Firth Maria , Moss Raymond , Karim Abdul‐Kadir , Firth Gary
Published: March 2003

Aims: To investigate the penetration of ciprofloxacin via different modes of administration into the aqueous humour using capillary zone electrophoresis and to determine its prophylactic role in ophthalmic surgery.

Methods: A prospective study was conducted of 84 patients, divided into two groups, undergoing routine cataract surgery and intraocular lens implantation. Forty patients received 750 mg ciprofloxacin orally the evening before and on the morning of surgery 12 h apart. Forty‐four patients received one drop of 0.3% topical ciprofloxacin 90 and 30 min prior to surgery. At the commencement of surgery 0.1−0.2 mL of aqueous fluid was sampled from the anterior chamber and assayed for ciprofloxacin concentration using capillary‐zone electrophoresis.

Results: The concentration of ciprofloxacin in the group receiving topical doses was less than 0.1 µg/mL, which is well below the minimum inhibitory concentration for cipro­floxacin inhibiting 90% (MIC90) of strains of Staphylococcus epidermidis (0.4 µg/mL). The mean concentration of ciprofloxacin in the aqueous humour of the oral group was 0.26 µg/mL with a standard deviation of 0.12 µg/mL (range 0.09−0.67 µg/mL) with only 12.5% achieving levels higher than MIC90 for S. epidermidis.

Conclusion: The topical ciprofloxacin 0.3% as given in this study achieved poor aqueous humour concentration. Oral ciprofloxacin given in this regime should not on its own be considered adequate prophylaxis in intraocular surgery. Capillary zone electrophoresis can be used as an alternative tool to the existing high‐pressure liquid chromatography methods for analysing ciprofloxacin level in the aqueous humour.
Colonoscopic extiripation of whipworms in patient with acute abdomen‐like symptoms
Authors: Horie Takahiro , Shimizu Ichiro , Ogata Tatsuro , Oshima Takasi , Mihara Miyuki , Yamashita Masatoshi , Ozaki Yuji , Yamamoto Koji , Iuchi Arata , Ito Susumu
Published: March 2003

A 25‐year‐old Indonesian male who had been living in Japan for the previous 2 years was hospitalized with sudden severe pain throughout his entire abdomen, but without abdominal guarding. Colonoscopy revealed 15 Trichuris trichiura whipworms in the cecum. These worms were extirpated using biopsy forceps. Immediately after extirpation, the abdominal pain disappeared. In Japan, whipworm infection with acute abdomen‐like symptoms at onset is extremely rare. In the present case, whipworm infection was diagnosed during colonoscopy, and the patient was simultaneously treated by extirpation of worms, thus indicating the utility of colonoscopy.
Endoscopic 13C‐urea breath test
Authors: Urita Yoshihisa , Miki Kazumasa
Published: March 2003

Background: Several modifications of the 13C‐urea breath test (UBT) for the diagnosis of Helicobacter pylori infection have been published. A new modification of UBT is described with the aim of avoiding the influence of urease activities from the commensal organisms other than H. pylori upon 13CO2 excretion in the breath.

Methods: The new modified UBT was performed in 295 consecutive patients undergoing esophagogastroscopy. After the collection of a baseline breath sample, an endoscopy was carried out. A baseline gastric gas sample was collected through a biopsy channel, and 20 mL of sterile water containing 100 mg of 13C‐urea was sprayed onto the gastric mucosa. The scope was drawn after spraying the 13C‐urea solution and collecting a gastric gas sample. Breath samples were collected 5, 10, 20 and 30 min after the spraying of 13C‐urea.

Results: The mean ± SD value of gastric gas samples for excess δ13CO2 in H. pylori‐positive patients was 1036.7 ± 1309.0‰, and 6.0 ± 23.3‰ in H. pylori‐negative patients. The cut‐off point as determined by receiver operator characteristic (ROC) curves for the gastric gas samples was 10‰. The sensitivity and specificity for this new method were 95.4% and 92.5%, respectively.

Conclusion: The method of endoscopically collecting 13CO2 gas in the stomach, which is not affected by the metabolism or by the absorption of 13C, provides an accurate and sensitive means for the detection of H. pylori.
A case of gastritis cystica polyposa showing a characteristic endoscopic ultrasonogram
Authors: Shudo Ryushi , Horita Kazutoshi , Takahashi Kuniyasu , Saito Tetsuya , Waku Katsuaki , Aoyanagi Yukihiro
Published: March 2003

Littler reported on the torose polypoid lesion observed at the site of gastroenterostomy long after gastrectomy and called it gastritis cystica polyposa (GCP). Since then, much attention has been paid to hypertrophic lesions at the sites of gastroenterostomy, and many reports on GCP have been published. This lesion often develops in patients who had gastroenteroanastomosis. It was observed by the authors that a submucosal tumor developed at the cardiac part of the stomach in a patient who had no history of gastrectomy. Very few cases of GCP were observed in unoperated stomachs. The tumor was excised by endoscopic mucosal resection and diagnosed histopathologically as GCP. Endoscopic ultrasonography before the operation revealed the presence of a spongy body filled with anechoic areas of various sizes under the mucosa of the tumor. This finding is characteristic of this disorder and is detailed here with a discussion on related papers.
Endoscopic Evaluation of Rectal Mucosal Reddening in Patients with Liver Cirrhosis
Authors: Motoyama Hirotaka , Ueki Junichi , Baba Yasuyuki , Asakura Hitoshi
Published: March 2003

Background:
Colonic mucosal lesions observed in patients with portal hypertension have been reported as portal hypertensive colopathy. We studied the rectal mucosa in patients with liver cirrhosis to evaluate the prevalence of mucosal reddening which looks like gastric red spots in the portal hypertensive gastropathy and to determine whether there is a correlation between this lesion and portal hypertension or the severity of liver disease.

Methods:
Seventy‐two patients with liver cirrhosis and 50 control subjects were examined. Colonoscopy was performed to evaluate the presence of mucosal reddening in the rectum. We investigated the relations between rectal mucosal reddening and esophageal varices, portal hypertensive gastropathy and the severity of liver cirrhosis.

Results:
Rectal mucosal reddening was observed in eight of 72 patients with liver cirrhosis but in none of the 50 control subjects; its prevalence in cirrhosis patients was significantly higher than that in the control subjects (P < 0.05). Cirrhosis patients with esophageal varices were more likely to have rectal mucosal reddening than cirrhosis patients without esophageal varices (P < 0.05). In addition, the occurrence of rectal mucosal reddening correlated with the severity of cirrhosis, based on Child–Pugh's classification (P < 0.05).

Conclusion:
We have shown that rectal mucosal reddening develops in patients with liver cirrhosis and is associated with the existence of esophageal varices and the severity of liver cirrhosis. These results suggest the possibility that portal hypertension and impaired liver function may play an important role in the pathogenesis of rectal mucosal reddening in patients with cirrhosis.
MINUTE SUPERFICIAL‐TYPE DE NOVO COLORECTAL CARCINOMA WITH SUBMUCOSAL INVASION
Authors: Yamada Hironori , Ikenobe Haruo , Maruyama Masakazu , Ichikawa Heizaburo , Ikegami Masahiro
Published: March 2003

A 59‐year‐old male was evaluated at the Foundation for Detection of Early Gastric Carcinoma after 4 years, following partial sigmoidectomy for early invasive cancer. Double‐contrast barium enema study and endoscopy revealed a new minute flat‐elevated lesion with an irregular central depression in the proximal sigmoid colon. Endoscopic mucosal resection was carried out with suspicious diagnosis of intramucosal colonic cancer. Macroscopically, the specimen constituted a flat‐elevated lesion measuring 4 mm in its largest diameter with a shallow irregular depression. Histologically, various‐sized vesicular nuclei and cribriform glands without adenomatous component were confirmed. A very small part of the lesion invaded into the submucosal layer. The diagnosis of carcinoma was made based on those histological findings, and this case was regarded as a minute superficial‐type de novo carcinoma. Radiographic and endoscopic findings were compared with the histological features in detail. Carcinoma was found at the depressed area on the surface of the lesion. Furthermore, the invasion of high‐grade carcinoma into the submucosal layer was located just beneath the deeper peripheral part of the depression which showed by colonoscopy. Consequently, a distinct depression on a flat‐elevated lesion may represent not only the presence of de novo cancer but also possible involvement of the deeper invasion.
Three‐dimensional endoscopic ultrasonography for the assessment of early gastric carcinoma invasion: could it provide diagnostic innovations?
Authors: SABET EMAN A. , OKAI TAKASHI , MINAMOTO TOSHINARI , MAI MASAYOSHI , SAWABU NORIO
Published: March 2003

Background: This study aimed to evaluate a three‐dimensional endoscopic ultrasonographic (3‐D EUS) system in the assessment of the tumor invasion depth of early gastric carcinoma.

Methods: Sixty‐nine macroscopically early cancer lesions in 67 patients were recruited in an in vivo study. The surgically resected gastric specimens of 30 of them
were re‐examined in an ex vivo study. An Olympus 3‐D EUS imaging system was employed in both studies. Diagnostic accuracy for tumor invasion depth was evaluated and compared with histopathological sections stained by H&E and Masson’s trichrome stain. Reconstructed surface‐rendering images were evaluated and compared with the endoscopic and macroscopic findings.

Results: Three‐dimensional EUS allowed rapid tomographic assessment of the lesions in both the in vivo and ex vivo studies. The accuracy of 3‐D EUS for the assessment
of tumor invasion depth was 87% in the in vivo study. The accuracy
rate was significantly lower (P = 0.03) for the cancer lesions associated
with ulcer fibrosis (74%) than for those with no fibrosis (97%).
In the 30 subjects who underwent both studies, the accuracy rates were higher in
the ex vivo than the in vivo study (94%vs 77%
for all the lesions, and 93%vs 74% for cancers associated
with fibrosis), but were not statistically significant. The rates of good surface‐rendering
images were 64% and 94% in the in vivo and ex vivo
studies, respectively. The differences were attributed to the clearer dual‐plane
reconstruction images obtained in the ex vivo study in absence of motion artifacts.

Conclusions: Three‐dimensional EUS is a promising imaging technique for the assessment of tumor invasion depth of early gastric cancer.
Laparoscopic cholecystectomy for cholecystolithiasis in a case with situs inversus totalis
Authors: Honda Masayuki , Takesue Fumio , Yasuda Mitsuhiro , Inutsuka Sadaaki , Nozoe Tadahiro , Korenaga Daisuke
Published: March 2003

We report a case of cholecystolithiasis associated with situs inversus totalis (SIT) that had been successfully treated with a laparoscopic cholecystectomy. Although cholecystolithiasis associated with SIT is rare, trained surgeons who perform unusual surgical procedures, even if they have not experienced such a case, would perform laparoscopic cholecystectomy for cholecystolithiasis associated with SIT easily and safely.
Efficacy of short‐course lansoprazole with clarithromycin and amoxicillin in the eradication of Helicobacter pylori in South‐East Asian patients: 5‐day t.d.s. versus 7‐day b.d. treatment regimens
Authors: Goh KL , Cheah PL , Tan YM , Rosmawati M , Ong KT , Lo YL , Chin SC
Published: March 2003

OBJECTIVE: To determine and compare the efficacy of 5‐day t.d.s and 7‐day b.d. treatment regimens comprising lansoprazole, clarithromycin and amoxicillin in the eradication of Helicobacter pylori.

METHODS: Patients with unequivocal evidence of H. pylori infection based on histology and rapid urease tests of both antrum and corpus biopsies were recruited for the study. The study was a randomized, investigator‐blind, comparative study. Patients received either 500 mg clarithromycin t.d.s. and 500 mg amoxicillin t.d.s. for 5 days (LAC5) or 500 mg clarithromycin b.d. and 500 mg amoxicillin b.d. for 7 days (LAC7) together with 30 mg lansoprazole (both groups) daily for either 5 or 7 days, depending on the treatment group. Patients were assessed for the successful eradication of H. pylori, defined as the absence of bacteria based on histology and urease tests on both antral and corporeal biopsies, carried out at least 4 weeks after completion of the therapy.

RESULTS: One hundred and eight patients were recruited for the study. In the LAC5 treatment group, four patients failed to return for follow up and in the LAC7 group, two failed to return for follow up and two were not compliant with medications. Eradication rates based on an intention‐to‐treat analysis were: 46/54 for LAC5 (85.2%; 95% CI = 72.9–93.4) and 47/54 for LAC7 (87.0%; 95% CI = 75.1–94.6). Based on a per protocol analysis, the rates were: 46/50 for LAC5 (92.0%; 95% CI = 80.8–97.8) and 47/50 for LAC7 (94.0%; 95% CI = 83.5–98.7). Both treatment regimens were convenient for patients and except for two patients in the LAC7 group, all patients reported taking 100% of all prescribed medications. The side‐effects encountered were uniformly mild and no patient discontinued treatment because of intolerance to medications. The most common side‐effects were altered taste (LAC5 64.7%; LAC7 78.8%). Diarrhea, nausea and anorexia were reported in a minority of patients.

CONCLUSIONS: Both the LAC5 t.d.s. and the LAC7 b.d. treatment regimens were well tolerated by patients and were highly effective in the eradication of H. pylori.
Effect of albumin infusion on preventing the deterioration of renal function in patients with spontaneous bacterial peritonitis
Authors: XUE Hui Ping , LIN Bing , MO Jian Zhong , LI Ji Qiang
Published: March 2003

OBJECTIVE: To determine whether plasma volume expansion with albumin could prevent impairment of renal function and reduce mortality in cirrhotic patients with either acute spontaneous bacterial peritonitis (SBP) or patients complicated with SBP.

METHODS: A total of 112 patients was randomly allocated to two groups: 56 patients were allocated to be treated with ceftriaxone and 56 patients were allocated to treatment with ceftriaxone plus intra‐venous albumin in 3 weeks. Serum creatinine and blood urea nitrogen levels were monitored.

RESULTS: Of the 56 patients (group 2) treated with ceftriaxone and albumin,
five patients had renal impairment. Of the 56 patients (group 1) treated with ceftriaxone
alone, 19 had renal impairment. The incidence of renal impairment was significantly
lower in patients treated with ceftriaxone and albumin (5/56; 10%) than in
patients treated with ceftriaxone alone (19/56; 34%; P = 0.002). In
addition, in‐hospital mortality in group 2 was 10% (5/56), but was 33%
(17/56) in group 1. Thus, in‐hospital mortality was significantly reduced from 33%
(17/56) in patients treated with ceftriaxone to 10% (5/56) in patients treated
with ceftriaxone and albumin (P = 0.01).

CONCLUSIONS: The addition of intravenous albumin to an antibiotic regimen reduces the incidence of renal impairment and mortality in cirrhotic patients with SBP.
Elderly case of duodenal ascariasis removed by endoscopy: A caution for ascariasis as a revived infection in Japan
Authors: Tanaka Yasuo , Uehara Takashi , Ryo Kyouka , Uegaki Satoko , Noguchi Sanshirou , Kino Kenji
Published: March 2003

A case of duodenal ascariasis in an 89‐year‐old woman is presented. Gastrointestinal endoscopy was performed for chest pain. During this procedure a cord‐like structure was found incidentally in the second part of the duodenum; it was removed and identified as a female specimen of Ascaris lumbricoides. Recently ascariasis in Japan has revived because fresh vegetables without agricultural chemicals are now common. Careful observation of the entire duodenum at gastrointestinal endoscopy is required in elderly patients, especially those in poor general condition as in the present case, because complications of ascariasis such as acute pancreatitis, acute cholangitis, and liver abscess may be more critical for them.
Arterial stiffness index: A new evaluation for arterial stiffness in elderly patients with essential hypertension
Authors: Kaibe Masaharu , Ohishi Mitsuru , Komai Norio , Ito Norihisa , Katsuya Tomohiro , Rakugi Hiromi , Ogihara Toshio
Published: March 2003

Background:  Arterial stiffness is one of the predictors of cardiovascular event. Arterial stiffness is commonly measured by pulse wave velocity between the carotid and femoral arteries. Recently the arterial stiffness index which is measured by computerized oscillometry at the upper arm was developed. As this procedure is a convenient means of measuring pulse wave velocity, we considered it suitable to evaluate arterial stiffness in elderly patients. We evaluated this arterial stiffness index and compared it with other methods of evaluating arterial stiffness in hypertensive patients, including the elderly.

Methods:  Forty‐two patients with essential hypertension, including 26 subjects over 60 years old were enrolled. We evaluated the arterial stiffness index by computerized oscillometry, and also evaluated arterial stiffness between the carotid‐femoral artery and the brachial‐tibial artery, the second derivative of photoplethysmogram, the forearm vasodilator response to reactive hyperemia by strain‐gauge plethysmography.

Results:  Arterial stiffness index was positively correlated with pulse wave velocity between the carotid‐femoral artery (P < 0.0001; r = 0.579), the heart‐carotid artery (r = 0.454) and right brachial‐tibial artery (r = 0.549). It was also correlated with b/a (r = 0.474) and d/a (r = 0.568) by a second derivative of photoplethysmogram, but not correlated with a reactive vasodilator response. In elderly patients, arterial stiffness index was also correlated with carotid‐femoral pulse wave velocity (P < 0.05; r = 0.456) but not correlated with a vasodilator response to reactive hyperemia.

Conclusion:  These data suggest that arterial stiffness index is correlated to common pulse wave velocity between the carotid and femoral arteries, so this index might be useful to evaluate arterial stiffness in hypertensive patients including the elderly.
Why barium enemas fail to identify colorectal cancers
Authors: McDonald Sharyn , Lyall Patrick , Israel Lincoln , Coates Richard , Frizelle Frank
Published: March 2003

Background:  The aim of the present study was to determine the cause and clinicopathological factors associated with the failure of barium enemas to detect colorectal cancers.

Methods:  A histopathological database was used to identify all patients with a diagnosis of colorectal cancer between 1991 and 1995. These records were matched with the records from patients who underwent barium enema examinations between 1990 and 1995. Those patients who had a colorectal cancer histologically diagnosed within 24 months of a barium enema in which no car­cinoma was seen, were identified. Where possible the radiology was reviewed. Failure to identify a carcinoma was then attributed to either simple failure, technical, interpretive or perceptive difficulties.

Results:  There were 967 patients with colorectal cancers treated in Christchurch Hospital during the study period 1991–1995. Matching of these patient details with all barium enema records revealed 313 patients who had barium enemas and histologically proven colorectal cancer. There were 21 (6.7%) patients in whom a carcinoma was missed. Of these, 18 had a barium enema within 8 months of surgery, and three were performed outside this timespan (15, 18 and 28 months, respectively). On review, 11 carcinomas could not be identified (nine due to technical error: poor coating (n = 1), overlapping loops (n = 3), single‐contrast enema (n = 4), faecal residue (n = 1)); and seven could be seen on review of the films (two interpretation errors, one technical and perceptive error, and four perceptive errors). In three cases films could not be found for review. In 16 of the 21 missed lesions the patient had a double‐contrast barium enema (DCBE) while five patients had single‐contrast barium enema (SCBE). The site and stage of missed tumours is presented.

Conclusions:  The most common reason for missed tumours was technical. The percentage of missed tumours in each region of the bowel correlates with the known incidence of tumours in each region and with a normal Dukes stage distribution, except in the caecum where the number of missed lesions was higher than expected.
Risks to feet in the top end: Outcomes of diabetic foot complications
Authors: O’Rourke Ian , Heard Sam , Treacy John , Gruen Russell , Whitbread Cherie
Published: March 2003

Background: The foot complications of diabetes are severe, disabling, costly and common in the Northern Territory. An understanding of the pathogenesis, the disease spectrum and treatment efficacy, however, is poor. The patterns of disease are documented in the present study; factors associated with good and poor outcomes are identified; and improved management strategies are proposed.

Methods: All patients presenting to the High Risk Foot Service at Royal Darwin Hospital between March 1997 and March 2000 were included in the present study, and details regarding the status of their feet, their demographics, their treatment and their outcomes were recorded prospectively. Logistic regression analysis was undertaken to determine associations between factors of interest and outcomes of healing and amputation.

Results: One hundred and twenty‐six patients were recorded, 41% of whom had neuropathic ulcers and 63% of whom had severe disease at presentation. Two types of diabetic foot pathology were recognized that are not usually classified: acute injury without neuropathy (10%) and deep soft tissue infection alone (9%).Thirty‐seven percent and 23% of patients required minor and major amputations, respectively. The total number of hospital bed‐days was 5813. Total contact casting was associated with good healing rates in 16 patients. Major amputation was associated with ischaemia, severe disease at presentation and increasing age.

Conclusions: Patterns of diabetic foot disease which are not commonly recognized are described in the present study; the severity and cost of the problem are documented; and some factors which lead to poor outcome, such as late presentation, are identified. Attention should be paid, through a multidisciplinary team, to timely referral from primary care, patient education, total contact casts and appropriate revascularization.
Intraoperative magnetic resonance: The future of surgery
Authors: Gluch Laurence , Walker David G.
Published: March 2003

Intraoperative magnetic resonance imaging (iMRI) is a new development in medicine that bridges the specialties of surgery and radiology. Deficiencies in the visualization of anatomical architecture and the perception of tumour boundaries in conventional open surgery have led to the integration of imaging within surgery. The superior soft tissue and multiplanar imaging features of magnetic resonance (MR) make this imaging modality superior to that of alternatives. The unique properties of MR to detect heat change and perfusion, and diffusion characteristics of tissue enhance the usefulness of this medium. Concurrent developments in computer aided image guidance and thermoablative technology, herald the era of minimally invasive tumour ablation. Applications have been developed for areas such as neurosurgery, general surgery, gynaecology and urology.
Retropharyngeal abscess in children
Authors: Dawes Laughlin C. , Bova Ronaldo , Carter Peter
Published: March 2003

Background:  Retropharyngeal abscess (RPA) is an uncommon, potentially fatal condition found more frequently in children than adults. Prompt diagnosis and surgical management of this condition is imperative to prevent complications including airway obstruction and mediastinitis. Few studies have been dedicated to paediatric retropharyngeal abscess.

Methods:  A retrospective analysis of 21 cases of retropharyngeal abscess at the Sydney Children's Hospital over a 12‐year period was performed.

Results:  There were 12 boys and nine girls involved in the analysis. Their ages ranged from 3 months to 12 years. Common ­presenting symptoms and signs included fever, dysphagia, neck swelling and torticollis. Respiratory compromise was present in 29% of the children at presentation. Foreign body ingestion accounted for 10% of cases. Seventeen cases were managed with surgical drainage. Surgical approaches adopted included transoral (70%), external cervical approach (20%) and a combined approach in 10%. There was no mortality. Mediastinitis occurred in two patients, one of whom also had recurrent laryngeal nerve palsy. No other serious complications occurred.

Conclusion:  Retropharyngeal abscess should be considered in all children presenting with neck pain and dysphagia. Prompt diagnosis and institution of appropriate medical and surgical therapy is imperative to prevent complications such as airway obstruction. The management of this condition should occur in a paediatric institution with appropriate medical, surgical and intensive care ­facilities.
Vitamin B12 malabsorption following bladder reconstruction or diversion with bowel segments
Authors: Ganesan Thirumalai , Khadra Mohamed H. , Wallis Jonathan , Neal David E.
Published: March 2003

Background:  Vitamin B12 is absorbed exclusively in the terminal ileum the resection of which may produce malabsorption of B12. The present study aimed to determine whether the length or specific segment of the intestine used in bladder reconstruction affects the overall incidence of B12 malabsorption. It was also aimed at the reasonable way of following these patients.

Methods:  Seventy patients who underwent urinary reconstruction between 1988 and 1997 were studied: 28 had undergone orthotopic reconstruction, 14 had ileal conduit diversion, 8 had continent diversion and 20 had undergone enterocystoplasty. The median follow up was 65 months (10−137 months). Indications for operation included carcinoma of the bladder, neurogenic bladder dysfunction, idiopathic detrusor instability and interstitial cystitis. Schilling tests were performed, and serum B12 level and haematological indices were measured.

Results:  Patients were classified depending on whether the ileocaecal junction was used. Group 1 included ileal conduit and entero­cystoplasty where 15−20 cm of ileum, 15−20 cm from ileocaecal junction was used. Group 2 consisted of orthotopic reconstruction and continent diversions where the ileocaecal segment was used. Group 3 comprised patients in whom long ileal segments (50−60 cm) had been used for reconstruction. Five patients in group 1 and one in group 2 had low B12 levels, but none had developed neuropathy or megaloblastic anaemia. One patient in group 1, and six patients in group 2 had low Schilling tests indicating intestinal malabsorption of B12. No patient in group 3 had a low B12 or an abnormal Schilling test.

Conclusion:  This study showed that use of ileocaecal segments results in intestinal malabsorption of B12. The length of ileum alone does not seem to be the determinant factor in causing B12 deficiency or B12 malabsorption.
Factors affecting surgical outcome in the elderly at Auckland Hospital
Authors: El‐Haddawi Falah , Abu‐Zidan Fikri M. , Jones Wayne
Published: March 2003

Background:  The aim of the present study was to define the factors which affect the outcome of major abdominal surgery in elderly patients.

Method:  Data were collected prospectively using the surgical audit on all patients who were 65‐years‐old or older and had undergone major abdominal surgery at Auckland Hospital between January 1997 and November 2000. Risk factors studied were age, sex, American Society of Anesthesiologists grade, operative duration, timing of surgery (elective, urgent or emergency), surgeon (consultant or registrar) and the presence of the scrubbed consultant in theatre. Surgical outcome (no complications, complications or death) was defined according to the complication stratification and severity score developed by the University of Otago. Direct logistic regression was used to determine the significance of the risk factors.

Results:  1141 patients (614 women and 527 men) who underwent 1248 procedures were studied. The factors that affected the mortality were the ASA grade (P = 0.0001) and operative timing (P = 0.0008). The factors that affected the severity of postoperative complications were ASA (P = 0.0001), operative timing (P = 0.0001) and duration (P = 0.0001).

Conclusions:  The ASA, timing and duration of surgery were the most significant factors affecting patient outcome. Age had a less important effect. Arranged surgery and short operative duration have a favourable outcome in selected elderly patients. Therefore, the elderly should not be denied indicated major abdominal surgery on basis of age alone.
New methodology for assessment of intimal hyperplasia of vascular prostheses
Authors: Hawthorne Wayne J. , Ao Peng Y. , Vicaretti Mauro , Fletcher John P.
Published: March 2003

Background:  When investigating the degree of formation of intimal hyperplasia (IH) quantification of the extent of the lesion is crucial to its assessment and analysis. The aim of the present study was to establish a new methodology (IH index) for estimating the degree of IH associated with vascular prosthesis implantation.

Methods:  Ten female Merino sheep underwent a standard gelatin sealed Dacron (GSD) patch grafting procedure in the left common carotid artery. The grafts were harvested 4 weeks following implantation and processed for assessment of IH by two methodologies − mean intimal thickness (MIT) and IH index. The advantages and disadvantages of the two methods for expressing the degree of IH were compared.

Results:  The IH index is less labour intensive but is as accurate as the MIT method in quantifying the IH lesion, statistical analysis showing high correlation and measurement agreement between the two methods.

Conclusion:  The IH index is a labour saving standardized methodology for quantification of IH in the current animal model.
Fractured zygomas
Authors: Tadj Armin , Kimble Frank W.
Published: March 2003

Background:  The purpose of this paper is to provide a review, based on collected data, on the topic of ‘fractured zygoma’. The review is presented under the headings of epidemiology, fracture patterns, treatment modalities and complications. Throughout the paper comparison is made with published data from around the world.

Methods:  A 10‐year retrospective audit was undertaken of all hospitalized patients, at the Royal Hobart Hospital, Tasmania, who had sustained a fractured zygoma. All Le Fort fractures involving the zygoma were excluded.

Results:  A total of 263 fractures was sustained, largely due to assault. Alcohol was a significant contributing factor. Tetrapod fractures were the most frequent type of fractures witnessed. Plating was the most frequently employed fixation. Inferior orbital nerve dysfunction and other complications were seen in 24.6% and 20.7% of follow‐up cases, respectively. Open reductions were nearly 4 times more likely to be accompanied by complications if inferior orbital nerve dysfunction was excluded.

Conclusions:  Both closed and open reductions are good treatment modalities and were used in near equal numbers of patients. There is a higher incidence of postoperative facial deformity in the closed reduction group, but more complications related to the incisions in the open reduction group. Open reduction and internal fixation is advocated for the unstable, markedly displaced or comminuted fractures. Silastic sheeting is a favoured graft for repair of the associated orbital floor defects and is associated with few complications.
MECHANICS AND MATERIAL ASPECTS IN PREDICTING SERVICEABILITY LIMITED BY STRESS‐CORROSION CRACKING
Authors: Leis  , Parkins
Published: March 2003

Stress‐corrosion cracking (SCC) involves the interaction between stress and the environment to cause cracking in situations where if present independently their effect would be benign. SCC involves mechanics through the role of stress and the material through its interaction with the environment. SCC has occurred in many engineering structures, generally without expectation that a specific combination of material and environment would produce such cracking. This paper discusses SCC and the development of models to quantify its effect on the life of structures—outlining both the approach and inherent complications due to the coupled mechanics and materials issues. This development is illustrated with reference to characterizing the initiation and early growth of SCC as it occurs on gas‐transmission pipelines. The discussion closes with consideration of failure criteria for use in this application, which involves the coalescence of several cracks with the rather complex patches of cracks that occur with SCC in this application. Areas needing further attention are identified.
FRACTURE MECHANICS AND FATIGUE: A HISTORICAL PERSPECTIVE
Authors: Paris
Published: March 2003

It was just 40 years ago that some of us became aware that the methods of Irwin’s ‘Fracture Mechanics’ could be applied to fatigue crack growth. After the first 10 years of establishing that approach, many things were known which impact this Symposium’s theme of prediction of structural life.

In the subsequent 30 years to the present, the Fracture Mechanics approach applied to life prediction has often been misused, or has ignored obvious characteristics which effect the precision and relevance of the predictions. This paper will emphasize some of these areas for improvements, which have been too often overlooked in practical applications. Some of the overlooked areas are:

(1) the misuse of crack propagation laws in life prediction;

(2) the modelling of crack shape effects in life calculations;

(3) the neglect of significant statistical effects and considerations for particular applications.

In conclusion, it is argued that life prediction methodology should be tailored to the application, rather than vice versa, which has all too often been the case.

Keywords—Crack growth; Fatigue; Fracture mechanics; Life prediction; Load interaction; Statistical effects.
HIGH RESOLUTION COMPUTED TOMOGRAPHY AND IMPLICATIONS FOR FATIGUE CRACK CLOSURE MODELLING
Authors: Guvenilir  , Stock
Published: March 2003

Understanding the physical bases of a cracked sample’s macroscopic response to applied loading, e.g. fatigue crack closure, requires non‐destructive, microscopic quantification of the crack face separations as a function of applied load. Ideally, these measurements should cover the entire crack face. Non‐destructive sectioning with high resolution X‐ray computed tomography has been used for in situ observations of the crack faces under applied load in samples of Al–Li 2090, and in this paper, the crack openings that were measured in the interior of the sample are related to crack face geometry and to changes in the slope of load–displacement curves. The implications of these results are discussed for physically based crack closure modelling.
A STUDY ON THE CHANGE OF FATIGUE FRACTURE MODE IN TWO TITANIUM ALLOYS
Authors: Wang H
Published: March 2003

The appearance of the fatigue fracture surface and crack growth curve have been examined for a Ti–2.5Cu alloy with different microstructures (two equiaxed and two lamellar microstructures), and for TIMETAL 1100 with a lamellar microstructure. With increasing ΔK, a slope change in the crack growth curve correlates with a transition in the fracture surface appearance (induced by a fracture mode transition); this being found in each microstructure. The microstructure size that controls the fatigue fracture is found to be the grain size for equiaxed microstructures and the lamella width for lamellar microstructures. The transitional behaviour can be interpreted in terms of a monotonic plastic zone size model in microstructures having a coarse microstructure size and in terms of a cyclic plastic zone size model for microstructures having a fine microstructure size.
A NOTCH INTENSITY FACTOR APPROACH TO THE STRESS ANALYSIS OF WELDS
Authors: Lazzarin P , Tovo R
Published: March 2003

In the context of linear elastic stress gradients that are present in welded joints, a stress field approach based on notch stress intensity factors is presented with the aim of describing stress distributions in the neighbourhood of weld toes, since fatigue strength is dependent on such distributions. This paper summarizes the analytical fundamentals and gives an appropriate definition of the parameters for stress components under opening and sliding modes. Then, by comparing the expected results with those obtained by numerical analysis, the contributions of the symmetric and skew‐symmetric loading modes are quantified for different geometries, and summarized into concise expressions which also take into account the influence of the main geometrical parameters of the welded joint. The range of validity and the application limits of this field approach in the presence of weld toe radii are discussed. Finally, a synthesis of experimental fatigue strength data based on the new field parameters is reported.
Competing roles of microstructure and flaw size
Authors: Mcgreevy  , Socie
Published: March 2003

Historically, engineers have relied on macroscopic properties, e.g. hardness and tensile strength to predict fatigue limits as analytical tools to model the process did not exist. Consequently, many empirical modifications to the fatigue limit have been made to account for variables, e.g. surface roughness, state of stress, inclusion content, environmental effects, etc. A mechanistic model is proposed to quantify the effects of these parameters on the fatigue limit of metals, specifically steels. Fatigue resistance, i.e. the threshold condition of a non‐propagating crack, is determined by two parameters: non‐propagating defect or crack size; and the strength of the barrier to crack propagation. The concept of three defect types associated with three different flaw‐dominated fatigue regimes is introduced. Furthermore, application of the model to fatigue mechanisms in high‐strength steels, synergistic effects of surface finish and intergranular cracks, competition between surface and subsurface fatigue nucleation, tempering, and scatter in fatigue behaviour is demonstrated. The model can be implemented in material screening, selection and processing, as well as a guide for future material research and design. Overall, the model is proven as a simple and robust tool for qualifying and statistically quantifying material behaviour.
Effect of post‐weld heat treatment on fracture toughness and fatigue crack growth behaviour of electron beam welds of a titanium (α+β) alloy
Authors: Mohandas  , Srinivas  , Kutumbarao
Published: March 2003

The effects of a post‐weld heat treatment on the fracture toughness and fatigue crack growth behaviour of electron beam welds of an α + β titanium alloy, Ti–6.5Al–1.9Zr–0.25Si have been studied. Welds in the stress‐relieved condition exhibited poor fracture toughness due to poor energy absorbing capacity of the thin α and α′ phases. Post‐weld heat treatment which resulted in the decomposition of α′ to α + β and the coarsening of intragranular and intergranular α resulted in improved toughness. This improvement in the toughness is related to improved ductility leading to crack blunting, crack path deviation at the thick intragranular and intergranular α phase. Fatigue crack growth resistance of welds was superior to the base metal in the α + β heat‐treated condition. The superior crack growth resistance of the welds is due to the acicular α microstructure which results in a tortuous crack path and possible crack closure arising from crack path tortuosity.
Fatigue crack growth threshold conditions at notches. Part I: theory
Authors: Vallellano  , Navarro  , Domínguez
Published: March 2003

A micromechanical description of the fatigue crack growth process at notches is presented. Crack interaction with the plastic slip barriers of the material (e.g. grain boundaries) and the influence of the notch stress gradient are intrinsically taken into account in the model. Both the notch fatigue crack initiation limit and the limit for propagation up to failure (i.e. the conventional notch fatigue limit) are clearly identified and calculated. The formation of non‐propagating cracks is also explained.
Cracking in PMMA containing U‐shaped notches
Authors: Gómez F. J. , Elices M. , Valiente A.
Published: March 2003

A procedure is proposed to evaluate the mechanical response (i.e. peak loads and load–displacement) of a notched component. A cracking criterion is given, applicable to quasi‐brittle materials under monotonic loading. This procedure is based on a cohesive zone‐crack model. Numerical predictions are in good agreement with a large experimental programme in which PMMA specimens of different shapes and sizes including U‐notch radius and U‐notch depth were tested. All experimental results are reported. The paper closes with a discussion of the proposed cracking criteria and some proposals for future work.
Compositional effects on the fracture behaviour of alkali–silicate glasses
Authors: Kingston J. G. R. , Hand R. J.
Published: March 2003

The two‐point bend strength and the fracture toughness of a series of soda–potassia–silicate and soda–potassia–calcia–silicate glass fibres have been measured. There is a clear variation of mean strength with composition for the soda–potassia–silicate glasses, however, there is much less variation of mean strength with composition for the soda–potassia–calcia–silicate glasses. There is also a greater variation of fracture toughness with composition for the soda–potassia–silicate glasses than for the soda–potassia–calcia–silicate glasses. The mean strength, fracture toughness and inferred flaw sizes for the soda–potassia–calcia–silicate glasses are all less than the equivalent values for the soda–potassia–silicate glasses. These results are related to the structural models and durability of the glasses tested.
Genetic algorithms for high‐precision reconstructions of three‐dimensional topographies using stereo fractographs
Authors: Minoshima  , Suezaki  , Komai
Published: March 2003

A software is developed which enables reconstruction of the three‐dimensional (3D) shape of fracture surfaces without human assistance. It is based upon computer image processing and pattern recognition techniques by using a stereo‐pair of scanning electron micrographs. The processing consists of two subprocesses: searching the matching points between two images; and computation of heights using the relative shift of the matching points. By using the previously developed system, some mismatches were inevitable in the search process, in particular, for low‐contrast SEM images, e.g. striations, intergranular facets, etc. In order to improve the accuracy of the search, a genetic algorithm (GA) was implemented into the developed system. By using the GA method, the 3D shapes of a wide variety of fracture surfaces including cleavage failures, intergranular cracking, dimples and fatigue striations, were successfully reconstructed with sufficient accuracy. The searching processes by the GA method and the previously developed two‐step algorithm of coarse and close searching were compared. These proved that the GA method has both the advantage of accuracy in the searching process and a short run‐time. A detailed 3D shape, of more than a 120 × 120 reconstructed point‐sized shape, was thus obtained with sufficient accuracy and with a relatively short run‐time.
An assessment of three creep–fatigue life prediction methods for nickel‐based superalloy GH4049
Authors: Chen L. J. , Wang Z. G. , Yao G. , Tian J. F.
Published: March 2003

High‐temperature low‐cycle fatigue tests with and without a 10‐s strain hold period in a cycle were performed on a nickel base superalloy GH4049 under a fully reversed axial total strain control mode. Three creep–fatigue life prediction methods are chosen to analyse the experimental data. These methods are the linear damage summation method (LDS), the strain range partitioning method (SRP) and the strain energy partitioning method (SEP). Their ability to predict creep‐fatigue lives of GH4049 at 700, 800 and 850 °C has been evaluated. It is found that the SEP method shows an advantage over the SRP method for all the tests under consideration. At 850 °C, the LDS and SEP methods give a more satisfactory prediction for creep–fatigue lives. At the temperatures of 700 and 800 °C, the SRP and SEP methods can correlate the life data better than the LDS method. In addition, the differences in predictive ability of these methods have also been analysed. The scanning electron microscopy (SEM) examination of fracture surfaces reveals that under creep–fatigue test conditions crack initiation mode is transgranular, while crack propagation mode is either intergranular plus transgranular or entirely intergranular, dependent on test temperature.