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PubMed2003

Inter- and intraobserver reliability of computed tomography in assessment of thoracic pedicle screw placement.

STUDY DESIGN: Reliability study of computed tomography imaging in 12 cadaver specimens instrumented with titanium or stainless steel thoracic pedicle screws. OBJECTIVE: To evaluate inter- and intraobserver reliability of computed tomography scan in determining the accuracy of thoracic pedicle screw placement and to identify the differences in observers' agreement when viewing stainless steel versus titanium screws. SUMMARY OF BACKGROUND DATA: Computed tomography is often used to assess the accuracy of pedicle screw placement. Accuracy of screw placement is important in the thoracic spine where pedicle morphometry increases the difficulty of screw placement (vital structures are at increased risk). The current literature lacks a critical evaluation of computed tomography reliability among observers. METHODS: Twelve adult cadavers were instrumented with thoracic pedicle screws. Nine cadavers were instrumented with titanium screws and three with stainless steel screws. The spines were imaged with computed tomography. Three observers used a grading scale to score the extent of pedicle violation and independently scored the placement of each pedicle screw on three separate occasions. Interobserver and intraobserver agreement were determined by using the kappa statistic. RESULTS: The mean kappa score for interobserver agreement for all 12 specimens (including titanium and stainless steel screws) was 0.51, which correlates with a moderate degree of agreement. Although the interobserver kappa statistics for titanium (kappa = 0.53) and stainless screws (kappa = 0.44) showed a moderate degree of agreement, the intraobserver reliability was substantial (kappa = 0.63). The mean intraobserver kappa for titanium screws was 0.63 and for stainless steel screws was 0.62. CONCLUSIONS: Our data show that interobserver agreement is moderate and intraobserver agreement is substantial when computed tomography is used to assess placement of thoracic pedicle screws. We conclude that computed tomography is reliable for evaluating thoracic pedicle screw placement throughout the thoracic spine.

Adult↗
PubMed2005

Width of the extended facial recess: a numerical study of ultrahigh-resolution computed tomography and its implications in minimally invasive otologic surgery.

BACKGROUND: Methods of minimally invasive computer-assisted otologic surgery lag behind other fields. The reason seems to be the extremely small dimensions of the corridors between important structures in the temporal bone and the fact that these structures are encased in bony frameworks, are obscured before drilling, and are not movable. The extended facial recess is a surgical pass to the tympanic cavity. It is bounded medially by the facial nerve and laterally by the tympanic annulus, and varies among individuals. For computer-assisted, minimally invasive temporal bone surgery, high-resolution definition is critically important. AIMS: To determine the width of the extended facial recess and evaluate the computerized findings as a pre- and intraoperative aid to otologic surgery planning. METHODS: Bilateral temporal bone high-resolution computed tomographic images of 100 male and 100 female patients were measured twice at five levels (caudal to cephalic), first using a window-independent algorithm (extended facial recess, full-width at half-maximum), implemented in a computed tomographic image-processing workstation, and then manually with calipers on the same axial computed tomographic images. RESULTS: As expected, the extended facial recess, full-width at half-maximum method yielded the widest values superiorly (4.15 +/- 0.41 mm in the female patients and 4.32 +/- 0.54 mm in the male patients). From this level down, the extended facial recess, full-width at half-maximum method yielded values that tapered gradually to 2.50 +/- 0.56 mm in the female patients and 2.42 +/- 0.46 mm in the male patients at the most interior level. The manual method (extended facial recess, computed tomographic images) yielded a significantly higher value than that obtained with the objective, window-independent method at all levels, and at some levels was higher by as much as one-third. At Level 2, which corresponded roughly to the round window, the extended facial recess was 4.00 +/- 0.65 in the female study group and 4.11 +/- 0.67 mm in the male study group. CONCLUSION: Image processing methods such as extended facial recess, full-width at half-maximum method might lead to fine tuning and thus improvement of computer-assisted otologic surgery. Before clinical application and complete dependence on these automated methods during otologic surgery, their reliability should be further validated.

Adolescent↗
PubMed2006

Update on the application of chest computed tomography scanning to cystic fibrosis.

PURPOSE OF REVIEW: To summarize the role of chest computed tomography as a tool to evaluate cystic fibrosis lung disease, and to describe what abnormalities can be detected using computed tomography and how computed tomography can be used in clinical practice. RECENT FINDINGS: Pulmonary function tests are only an indirect measure of lung structure, and are insensitive to localized and early structural abnormalities. Computed tomography is able to detect small areas with localized severe damage. The differentiation between normal and abnormal on computed tomography is relatively easy. In half of cystic fibrosis patients, the information obtained from pulmonary function tests is discordant with the information obtained from computed tomography. SUMMARY: Cystic fibrosis patients show lung inflammation and infection starting early in life. This leads to irreversible structural lung damage such as bronchiectasis and air trapping. Cystic fibrosis lung disease varies widely between patients. The primary aim of therapy is to prevent structural damage and to conserve lung function. Adequate monitoring of cystic fibrosis lung disease is paramount to tailor treatment to a patient's need. Computed tomography is currently the best tool to monitor lung structure, and pulmonary function tests are the best to monitor lung function.

Cystic Fibrosis↗
PubMed2001

Computer-aided characterization of mammographic masses: accuracy of mass segmentation and its effects on characterization.

Mass segmentation is used as the first step in many computer-aided diagnosis (CAD) systems for classification of breast masses as malignant or benign. The goal of this paper was to study the accuracy of an automated mass segmentation method developed in our laboratory, and to investigate the effect of the segmentation stage on the overall classification accuracy. The automated segmentation method was quantitatively compared with manual segmentation by two expert radiologists (R1 and R2) using three similarity or distance measures on a data set of 100 masses. The area overlap measures between R1 and R2, the computer and R1, and the computer and R2 were 0.76 +/- 0.13, 0.74 +/- 0.11, and 0.74 +/- 0.13, respectively. The interobserver difference in these measures between the two radiologists was compared with the corresponding differences between the computer and the radiologists. Using three similarity measures and data from two radiologists, a total of six statistical tests were performed. The difference between the computer and the radiologist segmentation was significantly larger than the interobserver variability in only one test. Two sets of texture, morphological, and spiculation features, one based on the computer segmentation, and the other based on radiologist segmentation, were extracted from a data set of 249 films from 102 patients. A classifier based on stepwise feature selection and linear discriminant analysis was trained and tested using the two feature sets. The leave-one-case-out method was used for data sampling. For case-based classification, the area Az under the receiver operating characteristic (ROC) curve was 0.89 and 0.88 for the feature sets based on the radiologist segmentation and computer segmentation, respectively. The difference between the two ROC curves was not statistically significant.

Algorithms↗
PubMed2001

Optimal scheduling of tracing computations for real-time vascular landmark extraction from retinal fundus images.

Recently, this group published fast algorithms for automatic tracing (vectorization) of the vasculature in live retinal angiograms, and for the extraction of visual landmarks formed by vascular bifurcations and crossings. These landmarks are used for feature-based image matching for controlling a computer-assisted laser retinal surgery instrument currently under development. This paper describes methods to schedule the vascular tracing computations to maximize the rate of growth of quality of the partial tracing results within a frame cycle. There are two main advantages. First, progressive image matching from partially extracted landmark sets can be faster, and provide an earlier indication of matching failure. Second, the likelihood of successful image matching is greatly improved since the extracted landmarks are of the highest quality for the given computational budget. The scheduling method is based on quantitative measures for the computational work and the quality of landmarks. A coarse grid-based analysis of the image is used to generate seed points for the tracing computations, along with estimates of local edge strengths, orientations, and vessel thickness. These estimates are used to define criteria for real-time preemptive scheduling of the tracing computations. It is shown that the optimal schedule can only be achieved in perfect hindsight, and is thus unrealizable. This leads to scheduling heuristics that approximate the behavior of the optimal algorithm. One such approximation produced approximately 400% improvement in the quality of the partial results at a defined milestone, as compared to random scheduling. The resulting algorithm can be readily implemented on conventional and multiple-processor systems, and is being applied to computer-assisted laser retinal surgery.

Algorithms↗
PubMed2002

Comparison of protein fragments identified by limited proteolysis and by computational cutting of proteins.

Here we present a comparison between protein fragments produced by limited proteolysis and those identified by computational cutting based on the building block folding model. The principles upon which the two methods are based are different. Limited proteolysis of natively folded proteins occurs at flexible sites and never at the level of chain segments of regular secondary structure such as alpha-helices. Therefore, the targets for limited proteolysis are locally unfolded regions. In contrast, the computational cutting algorithm considers the compactness of the fragments, their nonpolar buried surface area, and their isolatedness, that is, the surface area which was buried prior to the cutting and becomes exposed subsequently. Despite the different criteria, there is an overall correspondence between sites or regions of limited proteolysis with those identified by computational cutting. The computational cutting method has been applied to several model proteins for which detailed limited proteolysis data are available, namely apomyoglobin, cytochrome c, ribonuclease A, alpha-lactalbumin, and thermolysin. As expected, more cuts are obtained computationally than experimentally and the agreement is better when a number of proteolytic enzymes are used. For example, cytochrome c is cleaved by thermolysin at 56-57, 45-46, and at 80-81, and by proteinase K at 48-49 and 50-51. Incubation of the noncovalent and native-like complex of cytochrome c fragments 1-56 and 57-104 with proteinase K yielded the gapped protein species 1-48/57-104 and finally 1-40/57-104. Computational cutting of cytochrome c reproduced the major experimental observations, with cuts at 47, 64-65 or 65-66 and 80-81 and an unstable 32-47 region not assigned to any building block. The next step, not addressed in this work, is to probe the ability of the generated fragments to fold independently. Since both the computational algorithm and limited proteolysis attempt to dissect the protein folding problem, the general agreement between the two procedures is gratifying. This consistency allows us to propose the use of limited proteolysis to produce protein fragments that can adopt an independent folding and, therefore, to study folding intermediates. The results of the present study appear to validate the building block folding model and are in line with the proposal that protein folding is a hierarchical process, where parts constituting local minima of energy fold first, with their subsequent association and mutual stabilization to finally yield the global fold.

Apoproteins↗
PubMed1992

Effectiveness of computer-assisted perimetry in the follow-up of patients with pituitary microadenoma responsive to medical treatment.

DESIGN: Patients were studied before and after 1 year of bromocriptine or 6 months of SMS 201-995 treatment, for prolactinomas or GH-secreting adenomas, respectively. PATIENTS: Seventeen patients with intrasellar pituitary tumour (ten prolactinomas, all females; seven GH-secreting adenomas, four males and three females) and the presence of relative or absolute scotomas, were examined. MEASUREMENTS: We used computed tomodensitometry, Goldman perimeter and computer-assisted perimetry. RESULTS: The patients were divided into three groups according to their response to medical treatment as proved by computed tomodensitometry which revealed the disappearance of the tumour in four prolactinomas (group 1), a reduction > 40% in three prolactinomas and in three acromegalics (group 2) and no significant variation in the diameter of the adenoma in three prolactinomas and in four acromegalics (group 3). Comparison by the paired t-test of the visual fields before and after treatment revealed a significant positive change (P < 0.01) for all patients in groups 1 and 2 and for one patient in group 3, with disappearance of the scotomas in all cases in group 1 and in two cases in group 2. Visual field defects were detected by means of the Goldman perimeter in only one patient with prolactinoma and in two acromegalics, although the computer-assisted perimetry showed that, in 15 out of 17 patients, visual impairment was unilateral and in all cases the presence of relative scotomas was concentrated in the upper temporal quadrant. The visual defects observed with computer-assisted perimetry and the pituitary tumour dimension evaluated with computed tomodensitometry did not show significative correlations (r = 0.059, P NS). CONCLUSIONS: Computer-assisted perimetry was most useful in the diagnosis and follow-up of patients with pituitary adenoma, especially in the evaluation of small masses without subjective symptoms of visual loss, when the Goldman perimeter does not usually allow us to recognize minimal chiasmatic involvements or the improvement of visual field as a result of the medical therapy.

Acromegaly↗
PubMed1975

A computer-oriented linkage analysis scheme.

A comprehensive, computer-oriented scheme for genetic linkage analysis is described. It computes the likelihood of a complex pedigree allowing for many non-standard features including multiple alleles (up to four per locus), multiple mates, more than one mating in the eldest generation, consanguinity, missing or partially tested persons, and different recombination fractions between males and females. The program works by computing weighted likelihoods in a vertical, descending fashion. First, the set of possible genotypes for the members of the eldest generation is determined and prior probabilities assigned to these states of nature (based on gene frequency calculations). Phenotypic information is used to modify these probabilities in the standard manner. Then, for a particular set of genotypes, the conditional likelihood of the remainder of the pedigree is computed. This calculation may itself be many-branched and therefore a computer is necessary to keep track of the stages of the process. When the youngest generation has been taken into account, a final likelihood is determined, reflecting all information in the pedigree. The current version of the program successfully calculates the exact likelihood of a complex pedigree which was designed to exploit the non-standard features of the program. It has also computed likelihoods for a published pedigree, and the results are essentially equal to those obtained by the other authors using a previously available computer scheme for linkage analysis.

Diagnosis, Computer-Assisted↗
PubMed1998

Computers in medical education 1: evaluation of a problem-orientated learning package.

BACKGROUND: A computer-based learning package has been developed, aimed at expanding students' knowledge base, as well as improving data-handling abilities and clinical problem-solving skills. The program was evaluated by monitoring its use by students, canvassing users' opinions and measuring its effectiveness as a learning tool compared to tutorials on the same material. METHODS: Evaluation was undertaken using three methods: initially, by a questionnaire on computers as a learning tool and the applicability of the content: second, through monitoring by the computer of student use, decisions and performance; finally, through pre- and post-test assessment of fifth-year students who either used a computer package or attended a tutorial on equivalent material. RESULTS: Most students provided positive comments on the learning material and expressed a willingness to see computer-aided learning (CAL) introduced into the curriculum. Over a 3-month period, 26 modules in the program were used on 1246 occasions. Objective measurement showed a significant gain in knowledge, data handling and problem-solving skills. CONCLUSIONS: Computer-aided learning is a valuable learning resource that deserves better attention in medical education. When used appropriately, the computer can be an effective learning resource, not only for the delivery of knowledge. but also to help students develop their problem-solving skills.

Clinical Competence↗
PubMed1988

Transurethral prostatectomy with computer-monitored resectoscope.

Based on the difference in electrical conductivity between hyperplastic prostatic tissue and tissue of the surgical capsule, we have developed a monitoring computer that distinguishes the former from the latter. The computer sounds an alarm when the cutting loop of the resectoscope touches the capsule, followed by an automatic cut-off of the power source 0.4 s later; thus inadvertent perforation of the surgical capsule can be avoided in most cases. The function of the computer has been tested in 73 patients with benign prostatic hyperplasia. The results show that, with Nesbit's technique of transurethral resection, tiny perforations of the surgical capsule, usually 1 to 2 mm in diameter, occurred in all 30 patients operated on without computer monitoring, but only 3 of 73 computer-monitored patients had such an occurrence. There was a slight increase in the weight of resected prostatic tissue among the computer-monitored patients, but the difference between the time spent on the procedure between the two groups of patients was not significant. Apart from its monitoring function, the computer may reduce eye strain and mental stress in the surgeon, especially when resecting a large hyperplastic prostate.

Aged↗
PubMed1998

Home health nurses' initial experiences with wireless, pen-based computing.

Eight home health nurses from the Visiting Nurse Service of New York participated in a focus group discussion after their initial experiences using wireless, pen-based computing in the inner-city, home care environment. Transcripts of the nurses' responses to open-ended questions were analyzed and central themes were found, following the method of concept analysis described by Strauss and Corbin (1990). The central concepts were "Readiness," "A thousand pounds on my back," "Call for support," "Problems with transmission," "Using the computer as an assistant," "Nurses discovered glitches," and "Everybody has to have a computer." These themes reflected the nurses' initial experiences with the wireless computers and also revealed their concerns. This article will describe these themes and will discuss the implications of current improvements in wireless computing for health care. The focus group themes aided in understanding how this group of experienced home health nurses began to transition from handwriting on several different forms to checking-off items on a small, hand-held computer screen, from innovating methods to communicate when telephones were not available, to using a wireless computer to send and receive data involved in the patient admission process

Attitude of Health Personnel↗
PubMed1993

Computed tomography in the headache patient: is routine evaluation really necessary?

OBJECTIVE: To determine the likelihood ratio of a positive computed tomogram of the brain in the routine evaluation of headache patients. DESIGN: Consecutive patients with a chief complaint of headache were prospectively evaluated with computed tomography of the brain. Patients with headaches complicating other clinical disorders such as trauma, postictal state or known intracranial neoplasm were excluded. SETTING: Military tertiary care center. PATIENTS: Consecutive sample of 350 patients with a chief complaint of headache, regardless of the presence or absence of physical or neurologic signs, were referred for computed tomography of the brain. The patients were referred from a variety of inpatient and outpatient settings. RESULTS: Seven (2%) of the 350 patients had computed tomographic findings that were clinically significant. An additional 25 (7%) had positive computed tomographic findings, which were clinically insignificant for findings. All of the patients with significant computed tomographic findings had an abnormal physical or neurologic exam or unusual clinical symptoms. CONCLUSION: Routine computed tomography of the brain in headache patients with normal physical and neurologic exams and no unusual clinical symptoms has a low likelihood ratio for discovering significant intracranial disease.

Adolescent↗
PubMed1976

Computer interviewing of patients with epilepsy.

Epilepsy histories obtained by the computer interview were similar in substance and detail to histories recorded by house staff and attending physicians. In general, more information was obtained by the computer, and negative findings were consistently recorded by the computer. For potentially embarrassing questions, the computer may obtain more accurate information (Slack and Van Cura, 1968b). This might explain the contradictions concerning incontinence and medication. This preliminary study suggests that computer interviewing can provide a reliable method for obtaining epilepsy histories. The study also pointed out where changes in question wording and branching logic would improve the computer interview. These changes are being incorporated into the second version of the epilepsy interview. We hope computer-based interviewing will prove useful to patients and physicians in the diagnosis, treatment, and study of epilepsy.

Computers↗
PubMed1995

Computer analysis of monophasic action potentials: manual validation and clinically pertinent applications.

Monophasic action potential (MAP) recordings are increasingly being used in a variety of clinical and experimental situations but their manual measurement is cumbersome, especially when hundreds or thousands of beats must be analyzed to monitor the exact time course of action potential duration (APD) changes following heart rate alterations, during surveillance of APD alternans, or during the onset and stabilization of Class III drug effects. To facilitate this task we developed a computer program that automates programmed electrical stimulation, digitizes at 1-kHz sampling frequency MAP recordings up to 8 channels simultaneously, analyzes all APDs at repolarization levels from 10%-90% in 10% decrements (APD10-90), and automatically outputs the analyzed numerical data into spreadsheets for graphical display or statistical analysis. To validate the computer algorithm, two independent observers manually analyzed 585 concurrent MAP recordings at a paper speed of 100 mm/s. Cycle length measurements by the computer were precise to 0.4 +/- 0.5 ms as compared to the computer determined paced cycle length. Computer measurements of APD20, 50, and 90 differed from manual measurements by 2.0 +/- 8.8 ms, 0.7 +/- 7.9 ms, and 0.2 +/- 8.5 ms, respectively, for observer 1; and by 12.2 +/- 8.3 ms, 5.8 +/- 7.5 ms, and 1.4 +/- 10.1 ms, respectively, for observer 2. Inter-observer variability (IOV) was 10.3 +/- 11.1 (APD20), 5.1 +/- 9.0 ms (APD50), and 1.2 +/- 7.8 ms (APD90), which was similar to computer/observer-2 differences and significantly greater (0.001) than computer/observer-1 differences. This indicates that the computer analysis was at least as precise as manual measurements when compared to IOV, and more precise when comparing computer/observer-1 differences to IOV. While providing equal or greater precision, computer-aided analysis of 100 MAP signals took approximately 1 minute while manual analysis of the same data set took between 2.5 and 4 hours. The pacing and analysis software was subsequently applied to experiments that mimic clinically pertinent examples of MAP recordings: (1) automatic generation, analysis, and graphical display of electrical restitution curves at multiple ventricular sites simultaneously; (2) evaluation of myocardial pharmacokinetics by monitoring the progression of Class III antiarrhythmic drug effects by continuous MAP recordings, and displaying differences in drug action between multiple sites; (3) depiction of the adaptation time course of APD to abrupt changes in paced cycle length; and (4) quantitative analysis of APD alternans during myocardial ischemia. The results show that our computerized algorithm greatly facilitates the generation of cardiac electrophysiological, and clinically important, data.

Action Potentials↗
PubMedDate not supplied

Emergency thoracotomy: comparison of medical student, resident, and faculty performances on written, computer, and animal-model assessments.

OBJECTIVE: In clinical practice, thoracotomy and other critical emergency procedures are rarely required. Consequently, medical students and residents have difficulty acquiring procedural competency in these critical procedures. The authors developed objective written, computer, and animal-model assessments of thoracotomy procedural competency to permit comparison of the reliability and validity of these three procedural assessment modalities. METHODS: Thoracotomy procedural competency was evaluated for 18 persons at three levels of training (medical student, resident, faculty), using written, computer, and animal-model assessments. A prospective, sequential assessment design was used, with the examinees serving as their own controls. Procedural competency was defined in terms of performance time (animal time scale) and performance accuracy (written accuracy, computer accuracy, and animal accuracy scales) for three thoracotomy procedures (opening the chest, pericardiotomy, and aortic cross-clamping). Level of training was the independent variable, and procedural competency scores were the outcome measures. Confounding variables included previous thoracotomy and computer experience. RESULTS: Computer and animal-model assessments produced reliable results (Chronbach's alpha > 0.50). The animal time scale and computer accuracy scale best reflected the expected skill differences among levels of physician training, providing support for construct validity. In contrast, written and animal accuracy scale scores did not significantly differ by level of physician training. Moreover, previous thoracotomy experience (i.e., number of procedures previously performed) was not a significant predictor of procedural competency. CONCLUSIONS: This study demonstrates that critical emergency medicine procedures can be evaluated reliably and validly using computer simulation and animal-model assessments. Neither previous thoracotomy experience nor knowledge of procedure content adequately predicts thoracotomy competency.

Animals↗
PubMed2004

Reliability and validity of a brief questionnaire to assess television viewing and computer use by middle school children.

Sedentary behaviors, like television viewing, are positively associated with overweight among young people. To monitor national health objectives for sedentary behaviors in young adolescents, this project developed and assessed the reliability and validity of a brief questionnaire to measure weekly television viewing, usual television viewing, and computer use by middle school children. Reliability and validity of the Youth Risk Behavior Survey (YRBS) question on weekday television viewing also were examined. A brief, five-item television and computer use questionnaire was completed twice by 245 middle school children with one week apart. To concurrently assess validity, students also completed television and computer use logs for seven days. Among all students, Spearman correlations for test-retest reliability for television viewing and computer use ranged from 0.55 to 0.68. Spearman correlations between the first questionnaire and the seven-day log produced the following results: YRBS question for weekday television viewing (0.46), weekend television viewing (0.37), average television viewing over the week (0.47), and computer use (0.39). Methods comparison analysis showed a mean difference (hours/week) between answers to questionnaire items and the log of -0.04 (1.70 standard deviation [SD]) hours for weekday television, -0.21 (2.54 SD) for weekend television, -0.09 (1.75 SD) for average television over the week, and 0.68 (1.26 SD) for computer use. The YRBS weekday television viewing question, and the newly developed questions to assess weekend television viewing, average television viewing, and computer use, produced adequate reliability and validity for surveillance of middle school students.

Adolescent↗
PubMed1976

Randomised controlled trial of computer-held medical records in hypertensive patients.

A total of 278 hypertensive patients in three clinics were randomly allocated to have their medical records held in a computer system (136) or on standard hospital notes (142). For the computer system the doctor completed a structured input form, and the information on symptoms, physical findings, and diagnoses was more complete than that in the standard notes. This resulted in certain symptoms and risk factors being recognised more often when the computer system was used. The hypertension clinics' routines were not disrupted by the introduction of a computer-held system, and follow-up consultation times were not affected by the type of records kept, although the first consultation took eight minutes longer when computer documents were completed. The patients remained in the trial for one year and clinical management was assessed from blood pressure control, drop-out rates, and the frequency of performing investigations. These estimates of management showed no significant difference between the two groups, but the attempt to tailor the computer system to help management made the system acceptable to the doctors using it. The computer system continues to be used and is providing data for research into hypertension.

Computers↗
PubMed1993

Comparison of computed tomography, endosonography, and intraoperative assessment in TN staging of gastric carcinoma.

From 1986 to 1990 a prospective comparative study was undertaken to compare the relative accuracy of computed tomography, endogastric ultrasonography, and intraoperative surgical assessment in evaluating the depth of invasion (T category) and involvement of lymph nodes (N category) of patients with gastric carcinoma. One hundred and eight consecutive patients, who were treated by total gastrectomy and previously evaluated with computed tomography, endogastric ultrasonography, and intraoperative surgical assessment, entered the study. Results (T and N category) were compared with those of histopathological staging (pT and pN category). T categories were correctly staged in 43% of cases with computed tomography, 86% with endogastric ultrasonography, and 56% with intraoperative surgical assessment. Computed tomography scanning correctly staged 51% of all N1 and N2 lymph nodes compared with 74% for endogastric ultrasonography and 54% for intraoperative surgical assessment. In general, computed tomography was more accurate for advanced stages of cancer and showed a tendency to overstage the T category and understage N category of gastric tumours. By contrast, endogastric ultrasonography was equally accurate for all T categories and showed an understaging for N categories. Intraoperative surgical assessment overstaged early T stages, understaged T4 tumours, and was equally accurate for all grades of N categories. Computed tomography scanning and intraoperative surgical assessment of T and N categories were of little value in staging of gastric carcinoma. Endogastric ultrasonography is more accurate than computed tomography scanning and intraoperative surgical assessment. Therefore endogastric ultrasonography should be introduced in the preoperative assessment of patients with gastric carcinoma.

Adult↗