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PubMedDate not supplied

Heterogeneity of serum creatine kinase isoenzyme-MM in acute myocardial infarction.

Isoelectric focusing of serum creatine kinase (CK;EC 2.7.3.2) reveals up to 14 CK-MM subbands following acute myocardial infarction (AMI). The "normal" subbands 1 (pI 6.91), 2 (pI 6.65) and 3 (pI 6.35) are faintly present in normal serum and the "abnormal" subbands c (pI 7.25), e (pI 6.85), g (pI 6.50), i (pI 6.28), j (pI 6.20) and k (pI 6.15) are prominently detected in sera with elevated CK. "Abnormal" subbands a (pI 7.55),b(pI7.35),d(pI7.05),f(pI6.72) and h(pI6.40) have only been detected in AMI. The "abnormal" subbands appear, and reach maximum intensity (together with CK-MM 1-3), 3-12 h after infarction, and become faint and anodally convert (as do CK-MM 1-3) within 36 h. Similar changes are detected by nonequilibrium pH gradient electrophoresis which combines CK-MM and CK-MB analysis. In vitro incubation of serum with 0.015 M 2-mercaptoethanol induces conversion of CK-MM 1, 2 and 3 to b and c, d and e, and f and g, respectively. Thus, the complexity of the patterns is explained by a secondary conversion of "normal" to "abnormal" subbands superimposed upon anodal conversion of CK-MM 1----3. The clinical significance of these findings is discussed.

Adult↗

PubMed1989

Enhanced tumor growth and metastatic spread of an MH134 variant lacking a part of the MM antigen: a possible role of antibody-dependent cellular cytotoxicity in control of tumor growth and metastases.

The role of antibody-dependent cellular cytotoxicity (ADCC) in host defense against tumor growth and metastasis was investigated with MH134, an MM antigen-positive murine hepatoma, and MH134-M, a variant with enhanced tumorigenesis and metastasis, in syngeneic C3H/HeN mice. When inoculated subcutaneously into C3H/HeN mice, MH134-M tumors grew more rapidly than did MH134 tumors and consistently metastasized to the draining lymph nodes, whereas MH134 tumors did not. Also, MH134-M exhibited a significantly greater lung colonization potential than did MH134, when inoculated intravenously into C3H/HeN mice. In BALB/c nu/nu mice, however, solid MH134 tumors grew and metastasized to the same extent as MH134-M, indicating that there is no significant intrinsic difference between these two tumor lines in proliferative or metastatic capacity. Enzyme-linked immunosorbent assay (ELISA) and immunoblotting, performed after SDS-PAGE analysis of cellular extracts with a monoclonal antibody (MAb) that recognizes a part of the MM-antigen, revealed that the cells of MH134-M lack at least a part of the MM antigen. Sera of C3H/HeN mice bearing solid MH134 tumors were found to contain anti-MM-antigen antibodies, when tested by immunoblotting of SDS-PAGE-developed materials. Cytotoxicity testing in which thioglycollate-induced peritoneal macrophages were used as effector cells revealed that antibodies present in sera strongly induced ADCC to MH134 but not to MH134-M. On the other hand, sera of MH134-M tumor-bearing C3H/HeN mice neither contained anti-MM-antigen antibodies nor induced ADCC to MH134 or MH134-M tumor cells. Intravenous injection of carrageenan into C3H/HeN mice bearing solid MH134 tumors significantly enhanced tumor growth, whereas the growth of subcutaneously injected MH134-M tumors was not influenced by this treatment. These results suggest that the enhanced tumorigenesis and metastasis of the MH134-M line in C3H/HeN mice are based, at least in part, on significant loss of the MM antigen and the resultant inability to induce ADCC-triggering antibody production during tumor growth.

Animals↗

PubMed2006

Strengths and weaknesses of dark-lumen MR colonography: clinical relevance of polyps smaller than 5 mm in diameter at the moment of their detection.

PURPOSE: To assess the clinical relevance of dark-lumen MR colonography (MRC) for the detection of colorectal lesions using conventional colonoscopy (CC) and histopathologic examinations as reference standard. MATERIALS AND METHODS: A total of 72 patients underwent MRC and CC. MRC was performed using a contrast-enhanced high spatial resolution T1 weighted 3D volumetric interpolated breathhold examination (VIBE)-sequence. All removed colorectal lesions were evaluated by an experienced pathologist. RESULTS: CC confirmed 65 polyps less than 5 mm in diameter. Non of those lesions could be detected using MRC. Just two (4%) of the 49 removed lesions smaller than 5 mm showed signs of dysplasia. Additionally, CC confirmed 25 polyps between 6-15 mm in diameter (MRC 22). All those 25 lesions were removed in CC. Only four (16%) of those polyps showed signs of dysplasia and malignancy (11, 13, 13 and 15 mm). CONCLUSION: Dark-lumen MRC failed to detect all polyps smaller than 5 mm in diameter which are generally not clinically relevant at the moment of their detection and thus can be kept under surveillance. However, MRC as a non-invasive imaging modality is a promising alternative to CC in the detection of clinically relevant polyps larger than 5 mm in diameter.

Adult↗

PubMed1994

Conservative surgical treatment in cervical cancer with 3 to 5 mm stromal invasion in the absence of confluent invasion and lymph-vascular space involvement.

We have previously reported that simple hysterectomy is adequate therapy for microinvasive carcinoma of the cervix with less than 3 mm stromal invasion (Yajima, A., et al, Am. J. Obstet. Gynecol. 135, 685-688, 1979). However, whether it is possible to effectively treat patients with deeper stromal invasion remained in question. A policy for surgical treatment in patients with 3 to 5 mm invasion has not been standardized. Although radical hysterectomy is usually performed, some authors insist that patients with 3 to 5 mm invasion can be safely treated conservatively. Patients treated with conservative surgery should be carefully assessed because cases with confluent invasion or lymph-vascular space invasion have a greater potential for lymph node metastasis and carry a worse prognosis. Conservative treatment in this study was limited to patients with microinvasive carcinoma with 3 to 5 mm invasion, stage IB occult patients (classified by the FIGO 1973 staging system). The patients were preoperatively diagnosed with either carcinoma in situ or microinvasive carcinoma, and treated by conservative surgery (conization, simple hysterectomy, or extended hysterectomy). Twenty-two patients with 3 to 5 mm invasion but without additional risk factors, i.e., confluent invasion or lymph-vascular space involvement, were followed without postoperative radiation therapy. All patients survived except one (who died of an intercurrent disease) and there were no signs of recurrence of serious surgical complications. The present study with stage IB "occ" subjects suggests that conservative therapy rather than radical hysterectomy can be used in a very carefully selected subset of patients, i.e., in cases with 3 to 5 mm microinvasive carcinoma without additional risk factors, such as confluent invasion and lymph-vascular space invasion.

Carcinoma in Situ↗

PubMedDate not supplied

Structural and physicochemical analysis of the contractile MM phage tail and comparison with the bacteriophage T4 tail.

The three-dimensional (3-D) structure of the bacteriophage MM extended tail has been determined from electron micrographs of negatively stained specimens and compared with 3-D models of coprocessed extended bacteriophage T4 tails. Accordingly, the phage MM extended tail exhibits an axial repeat of 3.8 nm and can be indexed according to the integer helical selection rule l = -3n + 7m (n = 6n') compared to 4.1 nm and l = -2n + 7m (n = 6n') for the T4 phage tail. Compared to the T4 tail sheath, which reveals a stacked-disk-like appearance, the MM tail exhibits a more open structure, yielding an arrow-head-like appearance. Although the phage MM extended tail sheath is more stable than the T4 tail sheath under low-ionic-strength conditions, various chemical treatments of the MM tail sheath revealed responses, notably disassembly and contraction, similar to those previously described for the T4 tail sheath. Extended tails and their structural components contained in phage lysates or prepared by chemical degradation were compared in the EM, and the mass-per-length values of extended tails and tail tubes were determined by quantitative scanning transmission electron microscopy and compared to the corresponding values computed from the respective 3-D mass density maps. Accordingly, masses of 111 and 135 kDa/nm were obtained for the MM and T4 phage tail sheaths, respectively, with the corresponding tail tubes calculated at 19.3 and 25.5 kDa/nm, respectively. Although negative staining and freeze drying/metal shadowing of the two tails revealed different extended tail sheath structures, freeze-dried/metal-shadowed specimens of their contracted tails revealed very similar 6-fold symmetric axial repeats, with the subunits arranged on a pseudo-12-fold symmetric surface lattice following the integer helical selection rule l = n + 11m. In both cases tail contraction started at the baseplate and propagated headward as a wave forming a contraction gradient with a sharp boundary.

Bacteriophage T4↗

PubMed2004

Influence of detector collimation on SNR in four different MDCT scanners using a reconstructed slice thickness of 5 mm.

The purpose of this paper is to compare the influence of detector collimation on the signal-to-noise ratio (SNR) for a 5.0 mm reconstructed slice thickness for four multi-detector row CT (MDCT) units. SNRs were measured on Catphan test phantom images from four MDCT units: a GE LightSpeed QX/I, a Marconi MX 8000, a Toshiba Aquilion and a Siemens Volume Zoom. Five-millimetre-thick reconstructed slices were obtained from acquisitions performed using detector collimations of 2.0-2.5 mm and 5.0 mm, 120 kV, a 360 degrees tube rotation time of 0.5 s, a wide range of mA and pitch values in the range of 0.75-0.85 and 1.25-1.5. For each set of acquisition parameters, a Wiener spectrum was also calculated. Statistical differences in SNR for the different acquisition parameters were evaluated using a Student's t-test (P<0.05). The influence of detector collimation on the SNR for a 5.0-mm reconstructed slice thickness is different for different MDCT scanners. At pitch values lower than unity, the use of a small detector collimation to produce 5.0-mm thick slices is beneficial for one unit and detrimental for another. At pitch values higher than unity, using a small detector collimation is beneficial for two units. One manufacturer uses different reconstruction filters when switching from a 2.5- to a 5.0-mm detector collimation. For a comparable reconstructed slice thickness, using a smaller detector collimation does not always reduce image noise. Thus, the impact of the detector collimation on image noise should be determined by standard deviation calculations, and also by assessing the power spectra of the noise.

Artifacts↗

PubMed1999

Aortic regurgitant flow by color Doppler measurement of the local velocity 7 mm above the leak orifice--Part 2: Comparison with cardiac catheterization.

AIMS: An in vitro study of the flow convergence region in aortic regurgitation has shown that regurgitant flow rate can be derived from the local velocity V(7 mm) at 7 mm distance above the leak orifice. This clinical study was performed to test this method in patients. METHODS AND RESULTS: In 67 patients with aortic regurgitation, the flow convergence region was imaged by color Doppler. By analogy with the afore mentioned in vitro study, velocity profiles of the acceleration across the flow convergence region were read from the color maps. The profiles were fitted by using a multiplicative regression model. The V(7 mm) was read from the regression curve, and instantaneous regurgitant flow Q was derived from the V(7 mm) with the equation developed in vitro (Q = V(7 mm).cm2/0.28). Q showed a close association with the angiographic grade. Q-derived regurgitant stroke volume correlated significantly with invasive measurements by the angio-Fick method (r = 0.897, SEE = 19.9 ml, y = 0.88x + 5.9 ml). CONCLUSIONS: Within the color Doppler flow convergence region of aortic regurgitation, the local velocity at 7 mm distance to the leak reflects regurgitant flow rate.

Adult↗

PubMed1982

Relation of serum total cholesterol and triglyceride levels to the amount and extent of coronary arterial narrowing by atherosclerotic plaque in coronary heart disease. Quantitative analysis of 2,037 five mm segments of 160 major epicardial coronary arteries in 40 necropsy patients.

The amount of cross-sectional area narrowing by atherosclerotic plaques was determined histologically in each 5 mm segment of the entire lengths of the right, left main, left anterior descending, and left circumflex coronary arteries in 40 patients with fatal coronary heart disease and known fasting serum total cholesterol and triglyceride levels. The patients were divided into four groups based upon the serum total cholesterol and triglyceride levels: group I, total cholesterol of 250 mg/dl or less, triglyceride of 170 mg/dl or less; group II, total cholesterol of 250 or less, triglyceride of more than 170; group III, total cholesterol of more than 250, triglyceride of 170 or less; group IV, total cholesterol of more than 250, triglyceride of more than 170. The number of 5 mm segments of coronary artery narrowed severely (76 to 100 percent in cross-sectional area) by atherosclerotic plaques in each group was as follows: 172 of 505 (34 percent) 5 mm segments from group I; 242 of 353 (69 percent) segments from group II; 120 of 295 (41 percent) from group III and 425 of 884 (48 percent) segments from group IV. The mean percentage of 5 mm segments narrowed severely was significantly greater in group II than in group I (p less than 0.005) or group III (p less than 0.01). Additionally, the mean number of four coronary arteries per subject severely narrowed and the number of subjects with severe narrowing of the left main coronary artery were significantly greater in groups II and III than in group I. The percentages of 5 mm segments narrowed severely correlated significantly with the serum triglyceride level (p less than 0.03). Although it correlated with the number of severely narrowed coronary arteries per subject, the serum total cholesterol level did not correlate with the percentage of 5 mm segments of coronary artery with severe narrowing.

Adult↗

PubMed1983

Investigation of the heterogeneity of the MM isozyme of creatine kinase.

MM creatine kinase (MM CK) from human skeletal muscle was resolved into 21 subspecies by isoelectric focusing. Rabbit and bovine MM CK's were also shown to have patterns of 21 bands. These results are compatible with the presence of six different M subunit forms in skeletal muscle, which by random association into dimers, could produce 21 different subspecies of creatine kinase. Two-dimensional isoelectric focusing of human MM CK yielded a diagonal pattern, indicating that the various enzyme subspecies were not induced by ampholyte-protein interaction. Heat inactivated serum appeared to stabilize various CK subspecies and also produced one further anodally migrating MM CK form. Fresh serum had combined inhibitory and stabilizing effects on the MM CK subforms, and allowed for the identification of four anodally migrating CK subspecies not present in tissue extract. These findings are of critical importance because of the widespread use of CK isoenzymes in serum for diagnostic purposes.

Animals↗

PubMed1995

Study of the heterogeneity of creatine kinase-MM isoforms using western blotting.

OBJECTIVE: To study creatine kinase isoform variants in muscle (skeletal and myocardial) damage using a Western blotting procedure. DESIGN AND METHODS: The study comprised of 16 patients admitted with chest pain, 14 patients with skeletal muscle damage, and 4 healthy individuals. The creatine kinase-MM (CK-MM) isoforms were separated by isoelectric focusing and detected by electrophoretic transfer to a nitrocellulose membrane and immunoblotting. Binding of the first monoclonal mouse anti-human CK-MM antibody was detected by either a horseradish peroxidase or alkaline phosphatase anti-mouse immunoglobulin conjugate. RESULTS: Three major variants of CK-MM (MM3 pl = 6.8; MM2 pl = 6.4; MM1 pl = 6.2) were detected. Minor sub-bands were detected in 4/16 and 3/14 patients with acute myocardial infarction (AMI) and skeletal muscle damage, respectively. The tissue form (MM0 pl = 7.14) was visible in 6/16 patients with AMI and 4/14 patients with skeletal muscle damage. The appearance of minor variants was therefore of limited diagnostic value in discriminating between patients with and without AMI. Immunoblotting confirms the parallel increase in mass and activity of CK-MM isoforms, thus confirming measurement of isoform activity as an early marker of AMI or reperfusion following thrombolytic therapy. CONCLUSIONS: Study of isoform patterns gives more information concerning AMI and skeletal muscle trauma than is currently available from CK isoenzyme analysis. However, because CK-MM is also released in skeletal muscle damage, in such instances more discriminant markers of AMI are needed.

Adult↗

PubMed1984

Purification of five creatine kinase-MM variants from human heart and skeletal muscle.

Variants of creatine kinase-MM (variant of ATP:creatine N-phosphotransferase, EC 2.7.3.2), present in human heart and skeletal muscle, have been purified to homogeneity using DEAE-Sepharose column chromatography and column chromatofocusing techniques. Creatine kinase-MM I-IV were present in both heart and skeletal muscle, while MM-V was found only in heart. The number, ratio and elution profile of the variants during chromatofocusing remained identical even when they were purified in the presence of proteinase inhibitors. MM-I-V, on chromatofocusing, were eluted at pH 8.3, 7.9, 7.6, 7.2 and 6.8, respectively. Isoelectric focusing revealed the pI of MM-I-V to be 7.2, 6.9, 6.7, 6.4 and 6.2. Sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis showed a doublet pattern for creatine kinase-MM variants III-V. However, polyacrylamide gel electrophoresis without SDS indicated homogeneity because each variant showed a single band. The doublet pattern observed in the presence of SDS may reflect the presence of two subunits of slightly different mass.

Creatine Kinase↗

PubMed1991

Physiological, morphological, and physicochemical characterization of a novel Escherichia coli bacteriophage, phage MM.

A double-stranded DNA containing, T even-like, Escherichia coli bacteriophage, called MM, has been isolated from the local sewage and purified by polyethylene glycol precipitation followed by banding on a cesium chloride three-step gradient. It yields a burst size of 75 particles per infected cell, and has an adsorption coefficient of 3.3 x 10(-10) cm3/min and a latent period of 45 min. Electron microscopy of phage MM reveals an isometric icosahedral head, 92 nm long and 81 nm wide, and a 112-nm-long contractile tail with six pairs of 40-nm-long fibers attached to its baseplate. Phage MM appears similar to E. coli phage T4 or Salmonella phage O1. The density of phage MM in cesium chloride is 1.515 g/ml, and its total mass is 144 MDa. Gel electrophoresis of purified MM capsids displays two major capsid proteins in approximately equimolar amounts and with apparent molecular masses of 38 and 15 kDa. Similarly, purified MM tails yield two major polypeptides with apparent molecular masses of 55 and 16 kDa, most likely representing the major tail sheath and tail tube polypeptides. Its double-stranded DNA has a G-C content of 50%, a length of 131 kilobases (kb), and a mass of 89 MDa.

Adsorption↗

PubMed2004

Analysis of late risk of systemic blood pressures <120/80 mm Hg.

We studied categories of blood pressure (BP) <120/80 mm Hg as predictors of hypertension 10 to 22 years later by logistic regression analyses with 6 covariates. There was progressively increased risk for subjects with systolic BP 100 to 109 and 110 to 119 mm Hg (vs <100 mm Hg) or diastolic BP 70 to 74 and 75 to 79 mm Hg (vs <70 mm Hg). These relations were similar in men, women, and several ethnic groups but stronger in subjects <40 years old. These data suggest a definition of optimal BP of <100/70 mm Hg, similar to usual BP levels in children <10 years old.

Adult↗

PubMed2001

Experience with the 19-mm Carpentier-Edwards pericardial bioprosthesis in the elderly.

BACKGROUND: Valve replacement in small aortic root remains a surgical challenge. The objective of this study was to compare results of the 19-mm bioprosthesis with those of larger prostheses in the elderly. METHODS: The 443 patients, 70 years of age and older, who underwent aortic valve replacement with Carpentier-Edwards pericardial bioprostheses were reviewed. RESULTS: There were 93 patients with a mean age of 76+/-4 years with implantation of 19-mm prostheses and 350 patients with a mean age of 75+/-4 years with larger bioprostheses. Associated aortoplasty was performed in 10 patients (11%) with 19-mm bioprostheses and in 8 patients (2%) with larger bioprostheses (p = 0.001). There were 11 deaths (12%) within 30 days of surgery in patients with 19-mm prostheses and 22 deaths (6%) among those with larger prostheses (p = 0.1). The 7-year survival rate averaged 61%+/-7% in patients with 19-mm prostheses and 67%+/-4% in those with larger prostheses (p = 0.8). The 7-year freedom rates from all valve-related events averaged 96%+/-2% and 93%+/-2%, respectively (p = 0.6). CONCLUSIONS: Aortic valve replacement with the 19-mm Carpentier-Edwards pericardial bioprosthesis offers excellent midterm results in the elderly.

Actuarial Analysis↗

PubMed1998

Staging lymphoma with CT: comparison of contiguous and alternate 10 mm slice techniques.

PURPOSE: To compare two computed tomography (CT) techniques, contiguous 10 mm and alternate 10 mm slices of the chest, abdomen and pelvis, for initial staging of lymphoma. SUBJECTS AND METHODS: Fifty-two consecutive patients referred at initial diagnosis for lymphoma staging by CT were examined with contiguous 10 mm slices of the chest, abdomen and pelvis. Oral contrast was administered, but no intravenous contrast. Two sets of films for each examination were printed, one with 10 mm contiguous slices and one with 10 mm alternate slices. The two sets of films for each patient were reviewed separately in a randomized order and blinded fashion by two independent observers. Discrepancies were reviewed by a third observer and subsequently resolved by consensus. RESULTS: Staging assessments by both techniques were concordant in 51 of 52 cases: one patient was recorded as stage II on the alternate slice technique, but stage III with contiguous slices but this difference did not affect management. Inter-technique agreement was very good (kappa=0.97). The staging assessments showed discrepancies between the two observers in 12 of the 52 cases which were independent of technique (kappa=0.71; good agreement). Consensus review showed them to result from differences in perception in seven cases and differences in interpretation of abnormalities in five cases. CONCLUSION: Our findings support the use of an alternate 10 mm slice technique in the staging of lymphoma at initial diagnosis. Observer variation was greater than the difference between techniques.

Adolescent↗

PubMed1997

Corneal topography of excimer laser photorefractive keratectomy using a 6-mm beam diameter. Summit PRK Topography Study Group.

OBJECTIVE: The purpose of the study is to define qualitative patterns of corneal topography after excimer laser photorefractive keratectomy (PRK) using a 6-mm beam diameter, investigate changes in patterns over time, and identify associations of topography patterns with clinical outcomes. DESIGN: Multicenter, prospective cohort study. PARTICIPANTS: Ninety-eight eyes of 90 patients with myopia who had undergone PRK using the Summit Technology, Inc., excimer laser with a 6-mm beam diameter. INTERVENTION: Computer-assisted videokeratography data were analyzed for eyes having undergone PRK. Topography patterns at 3, 6, and 12 months after surgery were classified and associations with clinical outcomes assessed. MAIN OUTCOMES MEASURED: Topography patterns after PRK were determined at 3, 6, and 12 months after surgery. Associations with preoperative characteristics of age and attempted correction, and postoperative outcomes of uncorrected and spectacle-corrected visual acuity, predictability, astigmatism, corneal haze, glare, halo, and patient satisfaction were analyzed. RESULTS: At 1 year, 21.4% of corneas showed a homogeneous topography, 27.6% showed a toric-with-axis configuration, 10.2% showed a toric-against-axis configuration, 7.1% showed an irregularly irregular topography, 24.5% showed a keyhole/semicircular pattern, and 9.2% showed focal topographic variants. From 3 to 6 months, 40.1% of maps changed; from 6 to 12 months, 53.1% of maps changed, generally to optically smoother, regular patterns. Older age and higher attempted correction were associated with the development of more irregular patterns. The irregular groups showed worse predictability than did the regular groups and a tendency for slight overcorrection. The average reported glare/halo of 1.33 (scale = 0 to 5) in this study was less than in a previous study of the 4.5- to 5-mm treatment zone. However, of six patients expressing dissatisfaction with the results of surgery, three ranked their glare or halo at the maximum level. CONCLUSIONS: Topography patterns using a 6-mm beam diameter are identifiable, improve with time, and may affect clinical outcomes after photorefractive keratectomy (PRK). The keyhole/semicircular pattern is more prevalent with a 6 mm treatment zone than with smaller treatment zones. Although optical side effects of glare and halo appear to be reduced with the 6-mm treatment, a small number of patients still report substantial glare or halo after the procedure.

Astigmatism↗

PubMed2002

Imaging of 1.0-mm-diameter radiopaque markers with megavoltage X-rays: an improved online imaging system.

PURPOSE: To improve an online portal imaging system such that implanted cylindrical gold markers of small diameter (no more than 1.0 mm) can be visualized. These small markers would make the implantation procedure much less traumatic for the patient than the large markers (1.6 mm in diameter), which are usually used today to monitor prostate interfraction motion during radiation therapy. METHODS AND MATERIALS: Several changes have been made to a mirror-video based online imaging system to improve image quality. First, the conventional camera tube was replaced by an avalanche-multiplication-based video tube. This new camera tube has very high gain at the target such that the camera noise, which is one of the main causes of image degradation of online portal imaging systems, was overcome and effectively eliminated. Second, the conventional linear-accelerator (linac) target was replaced with a low atomic number (low-Z) target such that more diagnostic X-rays are present in the megavoltage X-ray beam. Third, the copper plate buildup layer for the phosphor screen was replaced by a thin plastic layer for detection of the diagnostic X-ray components in the beam generated by the low-Z target. RESULTS: Radiopaque fiducial gold markers of different sizes, i.e., 1.0 mm (diameter) x 5 mm (length) and 0.8 mm (diameter) x 3 mm (length), embedded in an Alderson Rando phantom, can be clearly seen on the images acquired with our improved system. These markers could not be seen on images obtained with any commercial system available in our clinic. CONCLUSION: This work demonstrates the visibility of small-diameter radiopaque markers with an improved online portal imaging system. These markers can be easily implanted into the prostate and used to monitor the interfraction motion of the prostate.

Equipment Design↗

PubMed1994

The maxillary-mandibular planes angle (MM degrees) bisector: a new reference plane for anteroposterior measurement of the dental bases.

A new plane, geometrically derived from the dental base planes, has been tested as an occlusal plane substitute for the measurement of anteroposterior jaw relationships. It lies close to but at an angle and inferior to the traditional occlusal planes and is highly reproducible at all times. Lateral cephalograms of 36 young adults (25 men and 11 women) and 43 10- to 12-year-old children (24 girls and 19 boys) were selected and the Wits technique of anteroposterior measurement was used to compare A-B values measured to the new plane with those measured to the functional occlusal plane (FOP) and to the traditional or bisecting occlusal plane (BOP). Because of the downward cant of the bisector anteriorly, B is projected onto it ahead of A in normal occlusion and coincides with A in skeletal (2) malocclusion. Mean values for normal occlusion were found to be approximately -4 mm for the children (-4.2 mm girls and -4.0 mm boys) and -4.5 mm for the adults (-4 mm women and -4.7 mm men).

Adolescent↗