Etiology of small bowel obstruction

BACKGROUND

Small bowel obstruction (SBO) is a major cause of morbidity and financial expenditure in hospitals around the world. The leading cause of SBO in the western world has become adhesions. The goal of this study was to determine the causes of SBO.

METHODS

The medical records of all patients admitted to one hospital between 1986 and 1996 with the diagnosis of SBO were reviewed retrospectively. This included 552 patients accounting for 1,001 admissions.

RESULTS

The etiology of SBO was adhesions (74%), Crohn's disease (7%), neoplasia (5%), hernia (2%), radiation (1%), and miscellaneous (11%). Patients with Crohn's disease were younger than patients with other etiologies. Surprisingly, recurrence rates were similar for patients treated operatively as for those treated nonoperatively with the exception in the hernia group where higher recurrence rates were noted for patients initially treated in a nonoperative manner.

CONCLUSION

The most common cause of SBO is adhesions followed by Crohn's disease and neoplasia.

Randomized trial of postoperative adjuvant chemotherapy with or without radiotherapy for carcinoma of the rectum: National Surgical Adjuvant Breast and Bowel Project Protocol R-02

BACKGROUND

The conviction that postoperative radiotherapy and chemotherapy represent an acceptable standard of care for patients with Dukes' B (stage II) and Dukes' C (stage III) carcinoma of the rectum evolved in the absence of data from clinical trials designed to determine whether the addition of radiotherapy results in improved disease-free survival and overall survival. This study was carried out to address this issue. An additional aim was to determine whether leucovorin (LV)-modulated 5-fluorouracil (5-FU) is superior to the combination of 5-FU, semustine, and vincristine (MOF) in men.

PATIENTS AND METHODS

Eligible patients (n = 694) with Dukes' B or C carcinoma of the rectum were enrolled in National Surgical Adjuvant Breast and Bowel Project (NSABP) Protocol R-02 from September 1987 through December 1992 and were followed. They were randomly assigned to receive either postoperative adjuvant chemotherapy alone (n = 348) or chemotherapy with postoperative radiotherapy (n = 346). All female patients (n = 287) received 5-FU plus LV chemotherapy; male patients received either MOF (n = 207) or 5-FU plus LV (n = 200). Primary analyses were carried out by use of a stratified log-rank statistic; P values are two-sided.

RESULTS

The average time on study for surviving patients is 93 months as of September 30, 1998. Postoperative radiotherapy resulted in no beneficial effect on disease-free survival (P =.90) or overall survival (P =.89), regardless of which chemotherapy was utilized, although it reduced the cumulative incidence of locoregional relapse from 13% to 8% at 5-year follow-up (P =.02). Male patients who received 5-FU plus LV demonstrated a statistically significant benefit in disease-free survival at 5 years compared with those who received MOF (55% versus 47%; P =.009) but not in 5-year overall survival (65% versus 62%; P =.17).

CONCLUSIONS

The addition of postoperative radiation therapy to chemotherapy in Dukes' B and C rectal cancer did not alter the subsequent incidence of distant disease, although there was a reduction in locoregional relapse when compared with chemotherapy alone.

The effect of the I1307K APC polymorphism on the clinicopathological features and natural history of breast cancer

The I1307K polymorphism in APC has been found to predispose to colorectal cancer in Ashkenazi Jews, and has recently been associated with an increased risk for breast cancer in the same population. In that study, we genotyped 205 paraffin-embedded breast cancers from Ashkenazi Jewish women diagnosed below the age of 65. We now present an extended analysis, with clinicopathological correlations between carriers of I1307K and non-carriers. Twenty-four of 209 cases (11.5%, 95% confidence interval 7.5-16.6) were found to carry the I1307K polymorphism. When stratifying the data by other relevant clinicopathological variables, we observed no association between the presence of this polymorphism and age at diagnosis (P = 0.52), grade (P = 0.074), tumour size (P = 0.99), lymph node status (P = 0.82), oestrogen receptor status (P = 0.23) or P53 immunoreactivity (P = 0.80). The breast-cancer specific 5-year survival for women with I1307 K polymorphism was 88.9% compared with 81.6% in women without I1307K (P = 0.34). Using microdissected samples and direct sequencing, no somatic mutations were observed in any of the 24 I1307K-positive cases. Single-strand conformation analysis of 158 of the I1307K-negative breast cancers that were available for study revealed no mobility shifts. We conclude that the presence of the I1307K polymorphism does not appear to be associated with any particular clinicopathological feature of breast cancer and importantly, does not affect the prognosis.

Ileoanal anastomosis with reservoirs: complications and long-term results

OBJECTIVE

To determine the rate of complications of ileoanal pouch anastomosis, their treatment and their influence on a successful outcome.

DESIGN

A computerized database and chart review.

SETTING

Three academic tertiary care health centres.

PATIENTS

All 239 patients admitted for surgery between 1981 and 1994 with a diagnosis of ulcerative colitis and familial adenomatosis coli.

INTERVENTIONS

Sphincter-saving total proctocolectomy and construction of either S-type of J-type ileoanal reservoir.

OUTCOME MEASURES

Indications, early and late complications, incidence of pouch excision.

RESULTS

Of the 239 patients, 228 (95.4%) were operated on for ulcerative colitis and 11 (4.6%) for familial polyposis coli. One patient in each group was found to have a carcinoma not previously diagnosed. Twenty-eight patients had poor results: in 17 (7.1%) the ileostomy was never closed or was re-established because of pelvic sepsis or complex fistulas, sclerosing cholangitis or severe diarrhea; 11 (4.6%) patients required excision of the pouch because of anal stenosis, perirectal abscess-fistula or rectovaginal fistula. Three patients died--of suicide, and complications of liver transplantation and HIV infection. Thus, 208 patients maintained a functioning pouch. The early complication rate (within 30 days of operation) was 57.7% (138 patients) and the late complication rate was 52.3% (125 patients). Pouchitis alone did not lead to failure or pouch excision. Emptying difficulties in 25 patients with anal stenosis were helped in 2 by resorting to intermittent catheterization. Patients with indeterminate colitis had a higher rate of anorectal septic complications, and all patients having Crohn's disease after pouch construction had complicated courses.

CONCLUSIONS

The complication rate associated with ileoanal pouch anastomosis continues to be relatively high despite increasing experience with this technique. Overall, however, a satisfactory outcome was obtained in 87% of patients.

The diagnostic value of routine intra-oral premaxillary radiographs in orthodontic assessment

OBJECTIVES

The purpose of this study was to determine whether significant dental abnormalities are likely to be overlooked in the anterior region of the maxilla if, in the absence of any clinical indication for further views, the only radiograph used during an initial orthodontic assessment is a good-quality orthopantomogram (OPT).

SAMPLE AND METHODS

Two orthodontists examined, retrospectively, the written and radiographic dental hospital records of 1169 consecutive, new, young patients who on their first visit to a dental teaching hospital underwent radiographic examination comprising an OPT and one or more supplementary radiographs of the anterior maxilla.

RESULTS

In five cases (0.43%) significant findings would have been overlooked if the intra-oral views had not been taken. These included periapical lesions and supernumerary teeth, but in three of the cases the image quality of the OPT was poor.

CONCLUSIONS

If the OPT is not routinely supplemented by intra-oral views, the chances of completely missing significant findings in the anterior maxilla are small, provided a thorough history and clinical examination have been completed and the image quality of the OPT is good.

Skeletal and dental changes following the use of the Frankel functional regulator

The purpose of this study was to assess the relative contributions of skeletal and dental components in correction of Class II division 1 malocclusions when treated with Frankel's functional regulator (FR). This was a retrospective study involving analyses of pre- and post-treatment cephalograms of 63 Class II division 1 patients treated with the FR to demonstrate the relative maxillary, mandibular, incisor, and molar movements during treatment compared with normal growth within a control group of untreated 39 Class II division 1 cases drawn from the same demographic population. All cephalograms were digitized and subjected to a Pitchfork analysis, which measured individual anteroposterior skeletal and dental changes during the period of study. It was shown that the FR was effective in treating Class II division 1 cases with the studied group being corrected to a clinically acceptable overjet and overbite of 2-3 mm. The majority of the correction came from dental movements, the most significant being the retroclination of the upper incisor teeth (mean 4.1 mm, 95 per cent CI +/- 0.44) and proclination of the lowers (mean 2.2 mm 95 per cent CI +/- 0.57). As regards skeletal correction, the most significant contribution was the restraint of normal maxillary forward growth (mean -0.2 mm, 95 per cent CI +/- 0.62) with forward mandibular growth not being a significant factor.

Decalcification in relation to brackets bonded with glass ionomer cement or a resin adhesive

Forty randomly selected patients had brackets bonded on one side of the of the maxillary labial segment with glass ionomer cement. Teeth on the opposite side were bonded with a resin adhesive. Teeth were assessed for decalcification pretreatment, at debond, and at review using a standardized photographic technique and a modified DDE index. The mean number of teeth affected by decalcification and the mean extent of decalcification per tooth increased during the treatment period, but from debond to review both of these measurements decreased for teeth bonded with either material (p)<0.01, t-test). Decalcification appears to become less severe posttreatment, but does not appear to be significantly affected during 12 to 18 months of orthodontic treatment by bonding with glass ionomer cement. Dietary and other environmental factors, including fluoride preparations, may be of greater importance in the prevention of decalcification during fixed appliance therapy.

Notching of orthodontic bonding resin to facilitate ceramic bracket debond--an ex vivo investigation

This ex vivo study assessed the potential of introducing a notch in the bond layer, as a means of facilitating the removal of ceramic brackets. Sixty extracted premolar teeth were divided into three groups of 20 teeth and bonded with Intrigue brackets using Concise chemically-cured adhesive. The bonding technique was modified with groups 1 and 2 by introducing a notch in the bond layer. Group 1 was notched from the gingival aspect, group 2 from the occlusal, and group 3 served as a control. The brackets were removed by applying a shear load from the gingival aspect using an Instron universal testing machine. The mean force to debond was calculated for each group. The results showed that introducing a notch significantly reduced the mean and maximal debond forces. This was confirmed with Weibull analysis with the notched specimens having a higher probability of failure at any force. In addition, ceramic bracket fracture was eliminated. Notching the bonding resin may be helpful in facilitating the removal of ceramic brackets.

I1307K APC and hMLH1 mutations in a non-Jewish family with hereditary non-polyposis colorectal cancer

We describe a French Canadian hereditary non-polyposis colorectal cancer (HNPCC) kindred which carries a novel truncating mutation in hMLH1. Interestingly, the I1307K APC polymorphism, associated with an increased risk of colorectal cancer, is also present in this family. The I1307K polymorphism has previously only been identified in individuals of self-reported Ashkenazi Jewish origins. In addition, in this family, there appears to be no relationship between the I1307K polymorphism and the presence or absence of cancer.

An ex vivo investigation into the effects of chemical solvents on the debond behaviour of ceramic orthodontic brackets

The problems of ceramic bracket debond have been well documented. A peppermint oil material has been marketed previously as a debonding agent. This study assessed ex vivo the effects of peppermint oil application on the debond behaviour of ceramic brackets compared with ethanol and acetone which are recognized softening agents. Intrigue brackets were bonded to 100 extracted premolar teeth. Groups of 20 bonded teeth were then placed in a test solution, control (distilled water), peppermint oil (5 minutes and 1 hour), acetone (1 hour), and ethanol (1 hour). The teeth were debonded using an Instron. Universal Testing Machine and debond forces recorded. The site of bond failure along with the adhesive remnant index was recorded for each tooth. One hour placement in peppermint oil produced the lowest mean and maximal debond forces (77 and 114 N, respectively). Weibull analysis showed that the probability of failure at 100 N was increased for the 1-hour peppermint group at 88 per cent compared with 52 per cent for the control. Placement in peppermint oil produced the lowest levels of retained resin. There was no evidence of enamel fracture with any of the groups, but bracket fracture remained a problem.

Continued change in the distribution of colorectal carcinoma

BACKGROUND

The aim of this study was to determine whether the previously reported shift in carcinoma from the left colon to the right colon has progressed.

METHODS

The charts of 2169 patients admitted to one institution between 1979 and 1994 with a diagnosis of colorectal carcinoma were reviewed retrospectively. The study was divided into four equal intervals. The large bowel was divided into five regions: right, transverse, left, sigmoid and rectum.

RESULTS

Right-sided lesions increased from 20.6 to 29.9 per cent (P = 0.001) and rectal lesions decreased from 22.0 to 11.3 per cent (P = 0.0002) from the first to the fourth study interval. The frequency of transverse, left and sigmoid colon lesions remained relatively constant.

CONCLUSION

The continuing trend of increased incidence of right-sided lesions and decreased incidence of rectal lesions was documented. Any screening examination for carcinoma requires total examination of the colon.

Fistulas complicating diverticulitis

This study was undertaken to assess the appropriate management of patients with diverticulitis complicated by fistula formation. A retrospective chart review was conducted on patients with symptoms of a fistula who presented between 1975 to 1995. There were 42 patients (32 women, 76%; 10 men, 24%) who ranged in age from 46 to 89 years (mean 69.8 +/- 9.8). Six patients had multiple fistulas. The types of fistulas included colovesical (48%), colovaginal (44%), colocutaneous (4%), colotubal (2%), and coloenteric (2%). Operative procedures consisted of resection and primary anastomosis in 38 patients and a Hartmann's operation in one. Three patients were managed conservatively with antibiotics (two due to poor performance status, the third due to resolution of symptoms). There were no operative deaths. The postoperative course was uncomplicated in 69%, while 12 patients (31%) experienced 19 complications (40%). These consisted of urinary tract infection (9.5%), atelectasis (7.1%), prolonged ileus (4.8%), arrhythmias (4.8%) and renal failure, myocardial infarction, pseudomembranous colitis, peroneal nerve palsy, unexplained fever, pulmonary edema (2.4% each). There were no anastomotic leaks and no deaths. Hospital stay ranged from 6 to 31 days (mean 12.3 +/- 7.6). Fistulas due to diverticulitis were safely managed by resection and primary anastomosis without mortality and with acceptable morbidity in this series. Patients deemed to be poor operative risks can be managed with a course of nonoperative treatment.

Lymphoproliferative disorders and motor neuron disease: an update

We studied 26 patients with both motor neuron disease and lymphoproliferative disease (LPD). Twenty-three patients had definite or probable upper motor neuron signs; none had electrophysiologic evidence of motor neuropathy. LPD syndromes comprised Waldenström's macroglobulinemia, multiple myeloma, chronic lymphocytic leukemia, follicular cell lymphoma, and Hodgkin's disease. In all but one patient, the cause of disability or death was neurologic. LPD was confined to bone marrow in 14 patients; eight of 14 had monoclonal paraproteinemia. One patient had LPD discovered at autopsy. Treatment of LPD in 20 patients resulted in neurologic improvement in 1 patient and arrest in another; both had progressive spinal muscular atrophy. Eleven patients were worse and 13 died. At least 30 cases have been reported from other centers, bringing the total to 56. Among the unusual reported concomitants were POEMS (polyneuropathy, organomegaly, endocrinopathy, myeloma, and skin changes) syndrome of myeloma and angiotropic lymphoma.

Lateral internal sphincterotomy for fissure-in-ano--revisited

PURPOSE

A disturbing complication rate following lateral internal sphincterotomy (LIS) has recently been reported, and this study assessed our complication rate.

METHODS

Charts of 312 patients who were operated on between January 1975 and December 1993 were reviewed.

RESULTS

There were 148 men (47.5 percent) and 164 women (52.5 percent), ranging in age from 16 to 95 (mean, 40) years. Two hundred sixty-five patients underwent LIS as a primary and sole procedure. Mean follow-up time was 20.4 months (range, 2 weeks-215 months). Healing times were less than one month (11.6 percent), one month (73.2 percent), one to two months (9.6 percent), and more than two months, 5.6 percent. Twenty-three complications (8.7 percent) occurred in 20 (7.5 percent) of the 265 patients: delayed healing (> 60 days) of the sphincterotomy site (13); persistence or recurrence of the fissure (3); wound infection (2); incontinence to flatus (1); soiling (1); temporary incontinence to flatus and stool (1); prolapsed hemorrhoids (1); fecal impaction (1). Most complications were minor and resolved spontaneously. Reoperations included one revision and one hemorrhoidectomy.

CONCLUSIONS

This review supports the belief that LIS is a good operation for patients with chronic anal fissure and can successfully be performed under local anesthetic as an outpatient procedure with an acceptable complication rate.

Determination of proliferative activity in colorectal carcinoma using monoclonal antibody Ki67

PURPOSE

In the search for a prognostic discriminant, Ki67 immunoreactivity of colorectal carcinoma was used to see whether this marker correlated with clinical and pathologic parameters and the ultimate prognosis of the patient.

METHODS

Fresh specimens from 30 surgically resected adenocarcinomas were obtained and frozen in liquid nitrogen. Slides were immunohistochemically stained with Ki67. Ten randomly chosen fields were examined, and 1,000 nuclei per specimen were counted. The percent positive stained nuclei determined the Ki67 score. Correlation was made with the parameters of Dukes stage, location within the colon, size of malignancy, gender, age, and survival.

RESULTS

There was a positive correlation of the Ki67 score for patients with metastatic disease, but no correlation was found to Dukes B and C cases. There was no correlation between Ki67 immunoreactivity and size or location of lesion, patient's age, patient's gender, or whether patient died of disease or developed a recurrence compared with those who survived five years disease-free.

CONCLUSION

Ki67 immunoreactivity could not be correlated with clinical and pathologic parameters except for metastatic disease in this study and was of limited use as a prognostic discriminant.

Re-examination of clinical manifestations and response to therapy of fissure-in-ano

PURPOSE

This study was designed to reassess clinical manifestations of fissure-in-ano, in particular, the frequency of constipation and rate of response to medical management.

METHODS

Records of 876 patients with fissure-in-ano seen between February 1975 and December 1993 were reviewed. Information gathered included age, gender, site, symptoms, bowel habits, associated anorectal problems, response, failure, and recurrence rates.

RESULTS

There were 439 women (51.1 percent) and 437 men (49.9 percent); mean age was 39.9 (range, 13.5-95) years. The fissure was located in the posterior mid line in 644 patients (73.5 percent), the anterior mid line in 144 patients (16.4 percent), both in 23 patients (2.6 percent), and only tenderness documented in 65 patients (7.4 percent). The fissure was located in the anterior midline in 12.6 percent of women and 7.7 percent of men. Dominant presenting symptoms included pain in 90.8 percent and bleeding in 71.4 percent of patients. Infrequent hard bowel movements (> or = 3 days) occurred in only 13.8 percent of patients. Mean follow-up was 26 (range, 0.5-215) months. A total of 44.7 percent of patients responded to nonoperative therapy, 60 percent of them in the first two months; of these, 18.6 percent developed recurrent symptoms. Of the latter group, 60 percent responded to further medical therapy, and 20 percent underwent a lateral internal sphincterotomy. Of the patients who initially did not respond to medical treatment (50.5 percent), lateral internal sphincterotomy was recommended.

CONCLUSION

Anterior fissures are much more common in both men and women than previously reported, and constipation and hard bowel movement are not universally present in patients with fissure-in-ano.

Bonded orthodontic retainers: the wire-composite interface

The bonded orthodontic retainer constructed from multistrand wire and composite is an efficient esthetic retainer, which can be maintained long-term. Clinical failures of bonded orthodontic retainers, most commonly at the wire/composite interface, have been reported. This in vitro investigation aimed to evaluate selected multistrand wires and composite materials that are available for use in the construction of bonded fixed retainers. An in vitro model was developed to simulate the forces encountered at the wire/composite interface. No significant difference was detected between different multistrand wire types and diameters with regard to retention in composite. Wires were placed in one of three groups according to surface characteristics identified with scanning electron microscopy. Increasing the thickness of composite overlying the wire increased the force required to detach the wire from the composite. Thickness of composite greater than 1.0 mm overlying the wire may give little clinical advantage. Greater force was required to detach the wire from Concise Orthodontic (3M Unitek) than any other composite tested. In vitro abrasion resistance testing found Heliosit Orthodontic (Vivadent) and Right On (TP Orthodontics, Inc.) to have poor abrasion resistance, whereas Concise Orthodontic and Transbond (3M Unitek) had abrasion resistance comparable with restorative composites. Clinical recommendations are made based on these findings.

Incidence and patterns of recurrence following curative resection for colorectal carcinoma

PURPOSE

This study was designed to determine incidence and patterns of recurrence after curative resection of colorectal carcinoma and to determine which variables are significant in predicting outcome.

METHOD

A retrospective review of 524 patients operated on by one surgeon from 1975 to 1992 was conducted. Variables recorded included age, gender, location, gross morphology, histology, stage of each primary and evidence of perforation and direct extension at time of original operation. Overall survival and pattern of recurrence were documented.

RESULTS

Overall recurrence rate was 27.9 percent. Anastomotic recurrence rate was 11.7 percent. Anastomotic recurrences were higher for rectal than colon lesions (20.3 vs. 6.2 percent; P = 0.001). Distant metastases developed in 14.4 percent of patients, 13.9 percent for colon carcinoma and 15.5 percent for rectal carcinoma. Average time for anastomotic recurrence was 16.2 months vs. 22.9 months for distant disease. T1,2,N0,M0 lesions had a 17.6 percent recurrence rate, T3,N0,M0 was 23.4 percent, and T1,2,3,N1,M0 was 43.7 percent (P = .001). Patients who did not undergo any intervention after diagnosis of recurrence survived an average of 28 months. Those who received palliative treatment survived an average of 39 months. Twenty-four percent of patients had reresection for cure, and 47 percent of these patients were alive at a mean of 80 months; those who died of their disease did so at an average of 53 months. Positive predictive factors for recurrence include site of lesion (rectum vs. colon), stage, invasion of contiguous organs, and presence of perforation. Age, gender, degree of differentiation, mucin secretion, and gross morphology were not found to be predictive factors in this study.

CONCLUSIONS

Recurrence after resection for rectal carcinoma is higher than after colon carcinoma. In those patients in whom reresection is possible, up to 50 percent may have long-term survival. Understanding patterns of recurrence and features that predispose to them may guide the physician in aggressive but more selective adjuvant therapy and recommendations for targeted surveillance in follow-up.

Results of local excision for rectal carcinoma

OBJECTIVE

To determine the results peranal excision for rectal carcinoma.

DESIGN

Retrospective case series.

SETTING

A university-affiliated hospital.

PATIENTS

Of 178 patients who presented for curative resection of rectal carcinoma between 1975 and 1993, 19 (10.7%) were deemed suitable for local excision. There were 10 men and 9 women with a mean age of 71.2 years. The follow-up ranged from 13 to 184 months.

INTERVENTION

Peranal excision.

MAIN OUTCOME MEASURES

Histologic differentiation, gross morphology, depth of invasion and size of the carcinoma, adequacy of margins of excision, complications of operation, rates of recurrence, results of salvage therapy and 5-year survival.

RESULTS

There were no intraoperative complications. Postoperative complications included urinary retention (one patient) and bleeding (one patient). There were five local recurrences (26%). Salvage operations were performed in three (60%) patients and were successful in two of them. The 5-year cancer-specific survival rate was 82%. The recurrence rate was higher in patients with inadequate margins of excision and ulcerative lesions. Neither size nor grade of the carcinoma correlated with recurrence.

CONCLUSIONS

Local excision of rectal carcinoma can be performed successfully in selected patients. Diligent follow-up is required, because up to 60% of local recurrences can be treated successfully.

Erroneous diagnosis corrected after 28 years. Not spinal muscular atrophy with ophthalmoplegia but minicore myopathy

OBJECTIVE

To correct, after 28 years, the previously reported diagnosis of ophthalmoplegia in a patient with presumed childhood spinal muscular atrophy.

DESIGN

Clinical follow-up, laboratory, electrophysiologic, and muscle biopsy data are provided.

RESULTS

The findings of clinical follow-up examination, electrophysiologic tests, and histologic examination of muscle specimens led to a revised diagnosis of minicore myopathy.

CONCLUSIONS

Spinal muscular atrophy was diagnosed in 1967, before histochemical techniques for examining muscle tissue and quantitative electromyography became widely available. Modern laboratory techniques later made the diagnosis of minicore myopathy possible. Progressive external ophthalmoplegia has been described in 24% of patients with minicore myopathy, but there have been only 7 reports of ophthalmoplegia with spinal muscular atrophy since 1954, and some of these diagnoses have been questioned.

Long source-skin distance rectal irradiation technique: a review of results

PURPOSE

This study reports the clinical outcome of fifteen patients with low rectal adenocarcinoma treated with the long source-skin distance (SSD) of endorectal irradiation technique. This method was designed at McGill University in 1986 as an alternative to the standard short SSD rectal irradiation that was developed by Papillon (Proc. R. Soc. Med. 66: 1179-1181, 1973).

METHODS AND MATERIALS

Between April 1986 and May 1993, six females and nine males were treated with this technique. Fourteen patients were treated with curative intent and one woman for palliation. The median total dose was 85 Gy (range 60-135 Gy) in a median of 3 fractions (range 3-5) over a median treatment time of 5 weeks (range 2-9.5 weeks).

RESULTS

With a mean follow-up of 39 months and a median of 24 months (range 3 months-8.7 years), actuarial overall survival and disease-free survival rates are 50.8% and 71.4%, respectively, at 8.7 years. No patients have died of recurrent disease, but one patient has distant metastatic disease. One patient treated with curative intent required an abdominoperineal resection for progressive disease. Treatments were tolerated well by all patients. Four patients required steroid enemas for localized proctitis for a short period of time. They all responded well and had complete resolution of symptoms.

CONCLUSIONS

Our results are comparable with those in other reports in the literature. The complications are similar in type and frequency to other published series. The long SSD technique may be an acceptable alternative to the standard short SSD technique.

Immunohistochemical analysis of statin in colorectal adenocarcinoma, polyps, and normal mucosa

PURPOSE

The search for an understanding of the kinetics of the malignant cell is an ongoing focus of research. The aim of the present study was to determine whether there were any differences in the expression of statin, a nonproliferation-specific nuclear protein, among different colorectal tissues and whether there is any relationship between statin presence and neoplastic aggressivity.

METHODS

The study population consisted of specimens from 19 patients who underwent resection for carcinoma, one for villous adenoma, and seven for colonoscopic polypectomies. Tissue samples were taken from the center of the specimen and from mucosa 10 cm from the lesion.

RESULTS

Statin immunoreactivity was evaluated by counting stained nuclei in ten randomly chosen fields, and percent of positive cells was calculated. Average percentage of statin-positive cells was 34.33 +/- 6.81 in the normal crypt, 44.42 +/- 7.28 for polyps, and 7.74 +/- 5.67 for carcinomas (significantly lower than normal mucosa and polyps; P < 0.001).

CONCLUSION

Statin expression is dramatically diminished in invasive carcinoma tissue, but it did not help determine aggressivity with respect to Dukes stage.

Diagnosis in neuromuscular diseases

The diagnosis of neuromuscular diseases can be challenging and successful in the majority of patients, due to advancements in electrophysiology, muscle and nerve biopsy immunohistochemistry, and cytogenetics. This article reviews diverse topics, highlighting these recent achievements, with an emphasis on how they affect the clinical and laboratory diagnosis of specific neuromuscular disorders.

Central pontine myelinolysis: clinical syndrome with normal serum sodium

Central pontine myelinolysis (CPM) is a rare syndrome generally linked to hyponatremia. Autopsy and imaging studies described demyelination in the central pons, in some cases combined with thalamic, internal capsular, hemispheric and cerebellar white matter lesions. The clinical syndrome and prognosis spans from asymptomatic patients displaying only imaging lesions to coma and death. Frequent findings are pyramidal tract and pseudobulbar signs. No effective treatment is known. Alcohol abuse is often associated. The imaging pattern of CPM is unique and generally accepted as diagnostic when other causes such as ischemia, multiple sclerosis, tumors, radiation, or pharmacological effects are ruled out. However, the exact mechanism of this selective process of demyelination remains obscure. The current major controversy concerns the role of therapeutic efforts of sodium level restoration in the etiology of CPM. We present a case of CPM where no hyponatremia was found. We hypothesize that (1) iatrogenic sodium restoration may not in all cases of CPM be the putative mechanism, (2) the clinical onset of CPM may in some patients represent a delayed response to an initially asymptomatic demyelination, and (3) normal admission sodium levels do not exclude the diagnosis of CPM.

An ex vivo study of self-, light-, and dual-cured composites for orthodontic bonding

It was postulated that using a dual-cured composite to bond orthodontic brackets could result in bond strengths comparable with those of chemically-activated materials and higher than those for light-activated materials. The shear bond strength of four composite resins used to attach mesh-backed orthodontic brackets was measured at 24 hours and following mechanical insult in the ball-mill. Analysis of variance and an SNK range test showed that at 24 hours Dual-cured Porcelite gave a significantly higher mean bond strength than the other materials (P < 0.05). However, following ball-milling the mean bond strength for Right-on was apparently significantly higher than that of the other materials. (P < 0.05). In this study, the mode of bond failure is also analysed and the use of Weibull analysis in bond strength testing is described.

Proliferative activity at rectal anastomoses performed with various suture materials. An experimental study

BACKGROUND

Suture line recurrence continues to be an important cause of failure following curative resection for colorectal carcinoma. Our aim was to determine whether the nature of the suture material used affected the proliferative activity of colonic crypt cells at the anastomosis.

METHODS AND MATERIALS

Sprague-Dawley rats were randomized into one control and three experimental groups. In each experimental group the proximal 2 cm of rectum were resected and anastomoses constructed with titanium clips, interrupted 6-0 Vicryl (Ethicon, Inc., Somerville, NJ), and interrupted 6-0 silk. Control animals had a sham operation. One-quarter of each group of rats were killed at 14, 30, 60, and 90 days. Each animal received intraperitoneal tritiated thymidine 30 minutes before death. Each anastomosis was harvested, and longitudinally oriented crypts were analyzed for the total number and position of labeled cells at five equal distances from the anastomosis. Random crypts were studied in the control group.

RESULTS

Labeling indices were increased in almost all experimental groups at days 14, 30, 60, and 90. There were no persistent, statistically significant differences in labeling indices among the various suture materials.

CONCLUSION

The type of suture material used did not significantly affect the proliferative rate in this animal model.

Effect of 5-fluorouracil and leucovorin on the integrity of colonic anastomoses in the rat

PURPOSE

This study was designed to determine the effects of 5-fluorouracil and leucovorin on the healing of colonic anastomoses and assess the safety of conducting a colonic resection and anastomosis during and shortly after a course of this chemotherapy in a rat model.

METHODS

Fifty-six male Wistar rats, weighing 200 to 250 gm, were divided into four groups, each consisting of 14 animals. Animals in Group I (control group) underwent colon resection and primary anastomosis. Animals in Group II received 10 mg/kg intravenous 5-fluorouracil and 10 mg/kg leucovorin once a week for four weeks and then underwent the same operation. Animals in Groups III and IV received the same drug dosage for six weeks and were operated at different intervals: Group III at one week and Group IV at two weeks after completion of chemotherapy. Within each group, one-half of the animals were sacrificed on the third postoperative day and one-half on the seventh postoperative day, and anastomotic bursting pressure measurements were performed.

RESULTS

At three and seven days, mean bursting pressure of the anastomoses were determined: 98 mmHg and 180.7 mmHg in Group I, 95 and 197.8 in Group II, 85.7 and 189.2 in Group III, and 98.6 and 179.2 in Group IV, respectively. There was no significant difference in bursting pressure between treated animals and controls by the third postoperative day or by the seventh day. The burst occurred at the anastomosis in all specimens tested on the third postoperative day and in the bowel wall adjacent to the anastomosis in all specimens tested on the seventh postoperative day.

CONCLUSION

This study demonstrates that the above regimen of chemotherapy has no effect on the healing of colonic anastomoses and that surgery can be performed safely during and shortly after this regimen of chemotherapy.

A retrospective review of a service to provide comprehensive dental care under general anesthesia

Day-stay general anesthesia is indicated for a number of dental reasons, not least for those patients who are unable to accept routine dental care. Since 1979, the Dental Hospital of the University of Newcastle upon Tyne, UK, has provided a weekly day-stay service for the dental care of such patients. Reviews of this service were undertaken in 1983 and again in 1993. The latter study investigated the provision of care for 265 patients and compared this with that for the 96 patients reviewed in the earlier study. This paper presents the results of the review and underlines the need for a very aggressive approach to preventive dental care for patients treated by this modality.

An investigation to estimate the fluoride uptake adjacent to a fluoride-releasing bonding agent

Decalcification of the teeth remains a problem during orthodontic treatment with fixed appliances. It has been suggested that bonding agents which release fluoride could supply it to the area of the tooth most at risk from decalcification. The aim of this study was to estimate uptake by enamel adjacent to a fluoride releasing bonding agent. Acid etch biopsies were used to estimate the concentration of fluoride in enamel adjacent to brackets bonded with Vitrabond and Geristore. Results indicate that there was a significant increase in the concentration of fluoride in enamel adjacent to Vitrabond. The clinical significance of the increase in the concentration of fluoride adjacent to Vitrabond and the mechanism by which fluoride moves from the material into the enamel remain unclear.

Expression of proliferation-specific genes in the mucosa adjacent to colon carcinoma

BACKGROUND

One of the main concerns in colon carcinoma therapy is local recurrence of the malignancy at the site of resection. Previous studies have shown that morphologically normal-appearing mucosa adjacent to colon carcinoma is different from mucosa distant from carcinoma. Mucosa adjacent to a carcinoma is characterized by crypt lengthening, cell hypertrophy, and change in production of mucopolysaccharides from sulfomucin in normal mucosa to sialomucins in carcinomas and adjacent mucosa. Recently there have been reports suggesting that there is an upward extension of the proliferative compartment in colonic crypts of this adjacent mucosa.

METHODS

Immunoblot analysis using antibodies to retinoblastoma, statin, c-Fos, c-Jun, and Cdc-2 proteins was used for our study on the expression of early cell cycle genes in carcinoma and its adjacent mucosa. In all, 15 tissue samples obtained from patients with colon carcinoma were analyzed. Tissue specimens were collected and immediately dissected as tumor, 0 to 1, 1 to 2, 2 to 3, 3 to 4, and 4 to 5 cm from the primary lesion. Dissected pieces were homogenized separately and subjected to immunoblot analysis.

RESULTS

We found upregulation of c-Fos, c-Jun, and Cdc-2 expression in carcinoma and adjacent mucosa up to 4 cm from the edge of the carcinoma. The phosphorylated form of retinoblastoma is present in the carcinoma as well as in adjacent mucosa up to 4 cm from the margin of the carcinoma. Furthermore, we observed that the level of statin, a nonproliferation-specific nuclear protein, is very low in the primary lesion and in adjacent mucosa up to 3 cm.

CONCLUSIONS

These results indicate that adjacent tissue up to 3 to 4 cm from the carcinoma has elevated levels of expression for cell cycle traverse-associated genes and down-regulation of nonproliferation-specific gene expressions such as statin. This imbalance indicates that within 3 to 4 cm from the edge of the carcinoma, colonic epithelial cells are already abnormal and may be in the hyperproliferative and preneoplastic state, susceptible to further steps leading to eventual malignant transformation.

Hepatic resection for colorectal liver metastases

The lack of other effective treatment for colorectal liver metastases makes hepatic resection a primary treatment consideration. Between January 1980 and December 1990, 26 selected patients with liver colorectal metastases who underwent hepatic resection were reviewed. The age, sex, site of primary lesion, histological grade, lymph node involvement, location, size, and number of hepatic metastases, type of hepatic resection, and preoperative CEA blood levels were documented. Complete removal with histologically negative resection margins were accomplished in 24 patients. The extent of resection performed was hepatic lobectomy in 12 patients. Segmentectomy in eight patients, and wedge resection in four patients. The 5-year survival rate was 30.5 per cent. Patients with metachronous metastases showed a better survival rate than those with synchronous lesions--46.6% versus 13.6% respectively (P = 0.08). None of the other factors studied showed a significant effect on survival. All patients were followed from the time of hepatic resection to the time of this study or death. During a median follow-up of 30.9 months, 20 patients developed recurrence of their disease (60 per cent in the liver). There was no perioperative mortality. Morbidity arose in 66.6 per cent of patients, with a majority of the complications being minor. We conclude that hepatic resection can be performed safely enough to be recommended in selected patients.

The effect of sandblasting on the retention of first molar orthodontic bands cemented with glass ionomer cement

This study examined the effect of sandblasting, in vitro, on the bond strength and survival time of first molar orthodontic bands. Survival time was assessed following simulated mechanical fatigue in a ball mill. The amount of cement left attached to the band after debanding was also assessed. In addition, the effect of sandblasting on the failure rate of 320 first molar bands cemented in 107 patients was examined in a half-mouth trial. Ketac-cem, mixed according to manufacturers' instructions was used as the luting agent for both laboratory and clinical trials. In vitro, sandblasting increased bond strength by 27 per cent (P < 0.01) and produced a three-fold increase in the median survival time relative to the untreated sample (P < 0.001) in the ball mill experiment. Sandblasting resulted in more cement remaining on the band rather than on the tooth enamel after band removal. In vivo, sandblasting reduced the clinical failure rate of the first molar bands (P < 0.001).

An investigation into the fluoride release of a variety of orthodontic bonding agents

The purpose of this study was to compare the fluoride release from a variety of orthodontic bonding agents. Fluoride release into de-ionized water was measured over a 20-week period. Material based on the fluoride exchange resin was also tested in a saline solution. Fluoride release from a variety of orthodontic bonding agents was compared and the amount of release found to be highly variable. Glass ionomer-based materials showed substantially greater fluoride release when compared with resin-based materials. The presence of anions (Cl-) did not improve the release from fluoride exchange resin. Glass ionomer/resin hybrid material (Vitrabond) released the greatest amount of fluoride.

The effect of artificial saliva on the frictional forces between orthodontic brackets and archwires

The effect of artificial saliva on the static and kinetic frictional forces of stainless steel (Dentaurum) and polycrystalline ceramic (Transcend) brackets in combination with 0.018-inch round and 0.019 x 0.025-inch Edgewise archwire sizes and stainless steel, nickel-titanium and beta-titanium archwire materials, under a constant ligature force were investigated. In all cases, artificial saliva had the effect of increasing the frictional force when compared with the dry state.

A look through the "retrospectoscope": reflections and realities on a decade of evolution of colorectal surgery in Canada. Colorectal guest lecture

Although the origin of colorectal surgery dates back to 1835, it has only been in the past decade that major strides in this specialty have been made in Canada. The Canadian Society of Colon and Rectal Surgeons was incorporated in 1983. Many other countries have also established national societies of colon and rectal surgery. In Canada, acknowledgement of the importance of the specialty has been slow for a number of reasons, not least of which have been concerns over turf. Nevertheless, it is unrealistic to expect a surgeon whose operative experience is spread thinly over numerous segments of surgery to equal the current achievement of various experts in only one of these fields. Despite their small numbers, members of the Canadian Society of Colon and Rectal Surgeons have made disproportionately large contributions to clinical care, teaching and research. A vibrant image and vital subjects of study will positively sustain the future direction of the specialty.

Selected operative management of fistula-in-ano in Crohn's disease

PURPOSE

The operative management of patients with fistula-in-ano in the presence of Crohn's disease has been controversial. Our aim was to review the results of operative treatment in this clinical setting.

METHODS

Twenty-eight such patients treated between 1976 and 1990 were reviewed. The duration of local symptoms, location of the Crohn's disease, medications, and previous operations were noted. An effort was made to classify the fistula-in-ano according to Parks' classification, but many fistulas were complicated and did not neatly fit into one of the described categories (intersphincteric 9, transsphincteric 10, complex 9). Patients underwent fistulotomy (three with a seton).

RESULTS

Complete healing was achieved in 71.4 percent of cases with an average healing time of 3.5 months (range, 3 weeks-26 months). With an average follow-up of 71 months (range, 12 months-14 years), postoperative function was good in 20 (71.5 percent) patients. Of the remaining eight patients, five ultimately underwent total proctocolectomy because of the severity of their colorectal disease, one patient developed alteration of continence, and two patients developed stenosis. There were two recurrences, (one at nine months and one at six years).

CONCLUSION

Operative treatment should be offered to selected patients with fistula-in-ano in the presence of Crohn's disease.

A 5-year clinical review of bond failure with a no-mix adhesive (Right on)

The performance of 5941 stainless steel orthodontic brackets bonded with a no-mix adhesive (Right-on) in 563 patients was reviewed over a 5-year period. The effects of age and sex of the patient, treatment mechanics, operator experience, and arch location on the failure rate and mean survival time (MST) of bonded orthodontic brackets were examined. The overall failure rate was 8 per cent (MST 45.7 months). The failure rate of brackets was three times greater in patients aged less than 12 years at the start of treatment compared with those aged greater than 16 years at the start of treatment. The MST was significantly different between male and female patients. Brackets bonded in patients treated with Begg mechanics had a greater failure rate than those bonded in patients treated with other appliance mechanics. The failure rates and MST of brackets were significantly affected by all the variables examined.

The shortened dental arch: supplementary analyses from the 1988 adult dental health survey

Information on 2297 dentate adults, aged 15-75+ years, who participated in the 1988 national survey of adult dental health in the United Kingdom, was reviewed in order to determine what proportion in each age group fulfilled the criteria for a 'shortened dental arch'. The proportion of people with four good quadrants was 90 per cent at 16-24 years falling to 2 per cent at 65-74 years. Overall, 54 per cent of the sample had four good quadrants. This is a more stringent measure of dental health than the proportion with 21 or more standing teeth, where the corresponding values were 100 per cent, 24 per cent and 80 per cent.

Proliferative activity at colonic anastomoses as determined by statin. A nonproliferation-specific nuclear protein

PURPOSE

One theory of anastomotic recurrence in large bowel carcinoma is that epithelial hyperplasia at the suture line causes metachronous carcinoma.

METHODS

S44, a monoclonal antibody directed against statin, a nuclear protein expressed in quiescent cells, was used to determine whether the anastomosis represents an area with a high proliferation rate. During follow-up colonoscopic examination of patients who had undergone previous resection for colorectal carcinoma, biopsies were taken from the anastomotic site and from the mucosa 10 to 15 cm from the anastomosis. One side of 10 well-oriented crypts was counted for each patient with the number of nuclei positive for statin being determined by the presence of dark brown reaction product.

RESULTS

The average percentages of statin-positive cells varied between 19.4 and 44.4 (average, 31.3 +/- 6.5) for the normal mucosa and 22.8 to 35.1 (average, 29.98 +/- 3.67) for the anastomotic mucosa. The differences were not significant. There were no differences between those patients in whom the postoperative time elapsed was two years or less and those greater than two years.

CONCLUSION

This study is unique in that the proliferative activity at the site of colonic anastomosis was determined in a clinical setting, and patients in which the anastomoses were created anywhere from 1 to 14 years earlier were included. Using S44 as a marker, this study does not support the theory that suture line recurrence is a result of an enhanced proliferation rate.

The prophylactic use of ureteral catheters during colorectal operations

The necessity for preoperative ureteral catheter insertion for colorectal operations continues to be controversial. To determine our experience and what complications might be associated with ureteral catheter use, the charts of all patients in our department undergoing ureteral catheterization in combination with colorectal procedures between the years 1978 and 1989 were reviewed. The indications for operation, the presence or absence of urinary tract symptoms, and intravenous pyelogram findings (if performed) were recorded. Time for the procedure, size and number of catheters, and complications were noted. From the operative report, a retrospective grading of necessity for ureteral catheterization was assessed according to a scale from A to D. There were 120 ureteral catheterizations performed, bilaterally in 60 per cent of cases. Complications included renal colic (1), oliguria (1), and anuria (2). Intraoperatively, one ureter was cut and one ureter tied but recognized by palpation and ligature removed. Retrospective grading deemed ureteral catheterization necessary in 27.5 per cent of cases. We conclude that catheters are helpful in selected cases. For patients with bilateral catheter insertion, complications can be reduced by ensuring urine output prior to removal of the second catheter.

A laboratory investigation into cements used to retain orthodontic bands

A laboratory study is presented where a technique of band retention testing is characterized. A glass polyalkenoate and a zinc phosphate cement were evaluated for band retention under simulated conditions of mechanical stress. In the absence of mechanical and other stresses there was no difference in the two cements for band retention. However, after mechanical stress was applied the glass polyalkenoate cement proved superior to the zinc polyalkenoate cement for band retention (P < 0.05). Weibull analysis is presented and described as a useful adjunct to statistical handling of band retention data.

Dental disease and current treatment needs in a group of physically handicapped children

One hundred and twenty-nine physically handicapped children (89 males, 40 females) were dentally examined in a local authority residential special school taking pupils from a wide geographical area in the Northern Region, for caries, periodontal disease, malocclusions and treatment need using World Health Organization criteria. The children were aged between 3 and 17 years with a mean age of 10.7 years. Mean deciduous caries experience (dft) was 0.9 and the mean permanent caries experience (DMFT) was 2.0. The mean dfs/DMFS values were 2.5 and 3.4 respectively. A higher experience of deciduous caries was found in girls, dft = 1.3, than in boys who had a mean dft value of 0.8 and in the permanent dentition girls had a mean DMFT value of 2.8 compared with 1.6 for boys. Each component of the index was also higher for girls in both dentitions. The gender difference identified in caries experience extended to treatment need for the permanent dentition, where more girls were recorded as requiring treatment than boys. Of the 129 children, 126 were assessed for treatment co-operation. Only 18 (14.3 per cent) were assessed as being amenable to routine dental care, 66 (52.4 per cent) were thought likely to present some management problems and the remaining 42 (33.3 per cent) were thought to require all their treatment under a general anaesthetic.