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PubMed1999

Alterations of the trabecular pattern of the jaws in patients with osteoporosis.

OBJECTIVE: The purpose of this study was to determine whether the morphologic features of the trabecular bones of the maxilla and mandible differ between patients with osteoporosis and normal controls. STUDY DESIGN: Periapical radiographs, obtained from dentists of 11 patients with osteoporosis and 12 control subjects, were digitized at 600 dpi. A custom computer program measured morphologic features of the trabecular architecture. The mean values for each feature were determined for the osteoporotic and control groups and compared by anatomic site. RESULTS: Twenty-four morphologic features of the trabeculae and marrow regions were examined in each anatomical site. A principal components analysis summarized these predictors to four. The Hotelling T (2) test found that patients with osteoporosis had significantly altered morphologic pattern in the anterior maxilla (P =.019) and the posterior mandible (P =.013) in comparison with the controls. A classification tree analysis separated all subjects into 2 groups with 92% accuracy. CONCLUSIONS: The data support the hypothesis that patients with osteoporosis have an altered trabecular pattern in the jaws in comparison with normal subjects.

Adult↗
PubMed1993

Computer assisted signal co-localization for simultaneous detection of antigen by immunohistochemistry and DNA by non-isotopic in situ hybridization.

A method has been developed to co-localize signals for antigen and DNA using a desktop microcomputer system (computer assisted signal co-localization). Antigens were detected by standard immunohistochemical methods and DNA was detected by non-isotopic in situ hybridization (NISH). Using this method, NISH signals can be precisely located in cells with well-preserved morphology captured by computer. The removal of the first immunohistochemical reaction products and reagents eliminates possible interference with hybridization and non-specific binding to the probe; therefore the sensitivity of the original NISH method remains. The captured NISH signals can be converted to any other colour which contrasts with the immunostaining. We have used detection of Epstein-Barr virus (EBV) and keratins as a model system. This method is straightforward, and with necessary modifications, will be applicable to any type of combined immunohistochemistry and in situ hybridization technique for simultaneous detection of antigen and nucleic acids or two types of nucleic acids in the same cells.

Antibodies, Monoclonal↗
PubMed2005

A comparison of craniofacial morphology in patients with and without facial asymmetry--a three-dimensional analysis with computed tomography.

This study intended to evaluate the morphological characteristics of the cranial base and maxillomandibular structures of facial asymmetry in adult patients, so as to determine whether mandibular asymmetry is a result of primary mandibular deformity or if it is influenced by cranial base deformity. Forty-two adult patients with dentofacial deformity were placed into two groups according to the deviation of the chin: Asymmetry group (n = 24) and Non-asymmetry group (n = 18). They were compared with three-dimensional (3D) CT reformatted images using a 3D visualization and analyzing program. The differences between the two groups, the correlation between the cranial base and maxillomandibular asymmetry were evaluated statistically. The degree of cranial base asymmetry in the Asymmetry group was not statistically different from the Non-asymmetry group. The asymmetric condyle position was found to be associated with skull base characteristics. The 3D position of the condyle and cranial base, however, was not closely related with mandibular asymmetry. The results showed that the cranial measurement variables were not the dominant factors that determined the degree of facial asymmetry. It seems that the mandibular skeletal factors itself, functional or intrinsic asymmetric growth potential, compensate or aggravate the influence of cranial asymmetry during the growth period.

Adult↗
PubMed1983

Cerebellar morphology in chronic schizophrenic patients: a controlled computed tomography study.

Simple, objective, linear, and density measures were used to evaluate by computed tomography (CT) the cerebellum-fourth ventricular region of 23 chronic schizophrenic patients and 23 normal controls. Our data suggest that a subgroup of chronic schizophrenic patients have cerebellar atrophy associated with a strong but nonsignificant trend toward increased cerebellar density. The implications of these findings are discussed in view of previous CT and neuropathological studies.

Adult↗
PubMed1987

Morphological brain abnormalities in schizophrenia determined by computed tomography: a problem of measurement?

The size of the cerebral ventricles was estimated from computed tomographic (CT) scans of 14 young patients with schizophrenia and 12 medical controls. The subjects were a representative subsample from a larger sample studied by Boronow et al. (1985). Although no CT abnormalities were detected in the psychiatric patients using traditional measures (mechanical planimetry for the lateral ventricles and a linear measure for the third ventricle), a volumetric analysis of the same 26 scans revealed enlargement of the lateral and third ventricles in the schizophrenics. The effect revealed by volumetric measures of the lateral ventricles was 58% greater than that obtained with digital planimetry and 96% greater than the effect found using mechanical planimetry. No differences were found between volumetric and digital planimetric measures of the third ventricle, but the effect revealed by the latter measure was 114% greater than that obtained by a linear index. It is suggested that volumetric measures of lateral ventricles based on information from several CT slices may be more sensitive to group differences in ventricular size than planimetry. Likewise, area measures of the third ventricle may be more sensitive to group differences than linear measures.

Adolescent↗
PubMed2006

Broca's area and inflectional morphology: evidence from broca's aphasia and computer modeling.

In a series of articles Ullman (2001, 2004; Ullman et al., 1997) has proposed that regular inflection is critically subserved by Broca's area. This suggestion is motivated by the finding that English speaking Broca's aphasics show selective deficits with regular inflection. Here we argue that this proposal does not hold cross-linguistically but is based on a confound between inflectional suffix and regularity that is specific to the English language. We present data from two experimental studies of participle inflection with 13 German and 12 Dutch Broca's aphasics. None of these aphasic speakers are selectively impaired for regular inflection but instead most of them show selective deficits with irregular inflection. These data suggest that a selective regular deficit is not a characteristic of Broca's aphasia across languages, and that Broca's area is not critically involved in regular inflection. To investigate the nature and localization of the processes underlying inflection we present a connectionist neural network model that accounts for the deficits of the German aphasic speakers. The model implements the view that the inflection of all verb types is based on a single mechanism with multiple representations that emerge from experience-dependent brain development. We show that global damage to this model results in a selective deficit for irregular inflection that is comparable to that of the German aphasic speakers. This finding suggests that a selective impairment of irregular participles as observed by German and Dutch aphasic speakers does not presuppose two distinctly localized mechanisms or processes that can be selectively affected by brain damage.

Adult↗
PubMed2004

Morphologic evaluation of cervical spine anatomy with computed tomography: anterior cervical plate fixation considerations.

The computed tomography (CT) studies of the cervical spine from 50 males and 50 females were reviewed to provide morphometric data on a variety of anatomic parameters relevant to anterior cervical reconstruction and fixation. Measurements were made of the vertebral body width and midsagittal anteroposterior (AP) diameter and the distance between the medial borders of the longus coli muscles. Distances between adjacent endplates were also measured, both at their midpoint and at the anterior margin. Widths of the vertebral bodies measure 24.6 +/- 2.4 and 23.0 +/- 2.4 mm in males and females, respectively, with the narrowest measuring 17 and 14, respectively. The average midsagittal AP diameter of each vertebral body in males was approximately 17-18 mm, with the smallest AP diameter measured to be 13 mm. The average midsagittal AP diameter of each vertebral body in females was approximately 15-16 mm, with the smallest being 10 mm. CT scanning provides excellent osseous detail for the measurement of such parameters, and with its widespread use in the evaluation of cervical disorders, large numbers of patients can be reviewed.

Adult↗
PubMed2003

Tracking cardiac electrical instability by computing interlead heterogeneity of T-wave morphology.

Oscillations in T-wave morphology, particularly T-wave alternans (TWA), have been fundamentally linked to increased susceptibility to ventricular fibrillation (VF). We investigated whether the escalation in complexity of T-wave oscillations before VF is attributable to increased spatial heterogeneity of repolarization. Peak interlead T-wave heterogeneity (TWH) was measured by second central moment analysis of T-wave morphology in epicardial electrograms in dogs during left anterior descending coronary artery occlusion. TWH differentiated cases in which myocardial ischemia provoked VF from those without VF (563 +/- 56 vs. 139 +/- 36 microV, P < 0.01). In the former group, progressive, significant increases in TWH above preocclusion baseline (70 +/- 8 microV) began at 2.25 min after the start of occlusion and were associated successively with TWA (at 155 +/- 19 microV), T-wave multupling (at 386 +/- 100 microV), complex oscillatory T-wave forms (at 560 +/- 76 microV), discordant TWA (at 572 +/- 98 microV), and VF at 4.36 +/- 0.14 min. TWH in precordial ECGs in 12 pigs during angioplasty-balloon-induced myocardial ischemia also discriminated animals that experienced VF (from 90 +/- 14 at baseline to 382 +/- 39 microV, P < 0.05) from those without VF (from 96 +/- 17 at baseline to 199 +/- 61 microV, NS). Ischemia-induced changes in ST segment and T-wave amplitude did not predict VF. Heightened spatial heterogeneity of repolarization, as assessed by second central moment analysis of TWH, underlies TWA and increased risk for ischemia-induced VF. Monitoring spatial TWH from precordial leads could prove useful in stratifying risk for life-threatening arrhythmias.

Algorithms↗
PubMedDate not supplied

3D-computed tomography: a new method for the evaluation of fetal cranial morphology.

This study is the first presentation of three-dimensional computed tomography (3D-CT) for the in vitro evaluation of the prenatal human cranium. The study was based on CT examinations from 26 aborted normal fetuses between 10 and 25 weeks gestational age. Incremental coronal and transverse CT slices of 1 mm thickness and a threshold segmentation algorithm were used to generate 3D-CT reconstructions (surface-shaded display, SSD) of the cranial bones similar to their anatomical appearance. The threshold of the segmentation algorithm was selected after comparison of the 3D-CT images generated with varying thresholds and graphically reconstructed histological serial sections of particular sutures in five specimens. The variation of the segmentation threshold resulted in alterations of the bone sizes and suture widths. However, 3D-CT images allowed sensitive identification of the cranial ossification centers and accurate evaluation of the bone topography. Cutting and rotating procedures made it possible to evaluate all imaged bones in arbitrary views without disturbing superpositions, thus making isolated examinations of particular macroscopic sections of the specimens unnecessary. In conclusion, 3D-CT of the fetal cranium promises to be of considerable help in the evaluation of prenatal cranial development.

Algorithms↗
PubMed1994

Femoral morphometry and anterior knee pain.

By computed tomography scan, morphology of the femur in 20 adult patients with anterior knee pain was compared with that of ten volunteers without knee pain to identify femoral characteristics associated with the painful patella. Anteversion, measured as the difference between the axis of the head-neck and the axis of the posterior condyles, was significantly greater in symptomatic adults (p < 0.01). Configuration of the distal femur and position of the patella relative to the femur were similar in each group. Adult anterior knee pain was, therefore, associated with increased anteversion without compensatory change in trochlear morphology or patellar orientation to the femur.

Adult↗
PubMed1996

Prediction of the in-vitro fertilization (IVF) potential of human spermatozoa using sperm function tests: the effect of the delay between testing and IVF.

To examine the diagnostic significance of several criteria of semen quality and to determine whether their prognostic value is eroded by the time interval between assessment and the attempt at in-vitro fertilization (IVF) with embryo transfer, 73 couples undergoing IVF and embryo transfer therapy were studied. The ability of human spermatozoa to achieve fertilization in vitro was examined in relation to the conventional semen profile, sperm morphology, the computer-aided assessment of sperm movement, ionophore-induced acrosome reaction, acridine orange staining, and chemiluminescent signals induced by phorbol ester and N-formyl-methionyl-leucyl-phenylalanine (FMLP). Spermatozoa were examined both in semen and after preparation on Percoll, some weeks prior to IVF. Fertilization rates were noted to be significantly correlated with elements of sperm movement characteristics, sperm morphology, and reactive oxygen species generation. Prediction of fertilization rates in a stepwise multiple regression analysis was obtained using four variables: sperm morphology, FMLP-induced chemi-luminescence and sperm movement characteristics (beat cross frequency and straightness) (r approximately 0.5). When multiple logistic regression analysis was used to predict which samples would achieve fertilization rates above and below a 50% threshold, three variables of predictive value including linearity, average path velocity and FMLP-induced chemiluminescence were selected. Combination of these variables classified the samples achieving good or poor fertilization with an overall accuracy of 83.6%. The time interval between semen assessment and IVF had little effect on the predictive value of these tests. In conclusion, the fertilizing ability of human spermatozoa is related to sperm morphology, attributes of sperm movement and reactive oxygen species production. The time delay between testing and IVF did not appear to affect predictive accuracy.

Acridine Orange↗
PubMed2005

The morphological compensatory change of peritubular capillary network in chronic allograft rejection.

To clarify the compensatory hemodynamic alterations in the interstitium of renal allograft biopsies with chronic rejection, we evaluated the morphological changes in the peritubular capillary (PTC) network. Seven renal biopsy specimens from recipients with chronic rejection presenting with elevation of serum creatinine of 1.9 +/- 0.5 mg/dL were examined. Renal biopsy specimens from their counterpart donors were used as normal controls. In each specimen, non-pathological interstitial areas without fibrosis, tubular atrophy or cell infiltration were compared with pathological areas (PA) showing fibrosis and/or tubular atrophy using a computer image analysis. Morphological measurements revealed that the mean cut surface area of the PTC in the non-pathological and pathological interstitial areas in the recipient biopsies were significantly larger than that of the normal controls (p < 0.001 and 0.001, respectively). In the recipient biopsies, both of the mean cut surface areas of the tubules and PTC in the non-pathological areas were significantly higher than those in the PA (p < 0.001). The mean glomerular diameter in the recipient biopsies was also significantly higher than that of the donors (p < 0.01). In this study, we provided pathological evidence for the compensatory interstitial and glomerular hemodynamic alterations in kidney graft with chronic rejection and the condition as single kidney.

Adult↗
PubMed1990

Relationship of corneal endothelial morphology to diabetic retinopathy, duration of diabetes and glycemic control.

Using specular microscopy and computer-assisted morphometry, the morphologic features of the corneal endothelium were evaluated in three groups of patients with type II diabetes mellitus: 20 patients without diabetic retinopathy, 24 with background retinopathy, and 26 with proliferative retinopathy. When compared to age-matched nondiabetic controls (30 patients), all diabetic groups had similar endothelial cell densities but demonstrated significant increases in cell size and shape variability (pleomorphism). However, there was no significant difference in the degree of these endothelial changes among the three diabetic groups. Moreover, none of the endothelial morphologic parameters was found to correlate with the duration of diabetes or glycemic control, as estimated from glycosylated hemoglobin (HbA1) concentrations.

Adult↗
PubMed2004

Radiographic examination of the mandibular (glenoid) fossa in ancient and modern man.

OBJECTIVE: To compare the morphology of the mandibular (glenoid) fossa between ancient and modern Japanese. METHODS: There were 221 specimens from the ancient period and 206 specimens from the modern period. Radiographs of the mandibular fossa were obtained using a modified Schuller technique and were studied. The length, depth, and area of the mandibular fossa and angulation of the frontal slope of the mandibular fossa on the radiographs were automatically computed. In addition, morphological changes of the mandibular fossa in the ancient or modern periods on radiographs were evaluated in order to assess tendency of temporomandibular joint disorder (TMD). RESULT: The ratio of mandibular fossa having morphological alternation in the modern period was greater than that in the Yayoi. Differences in the length and area between the right and left sides became progressively larger from the Yayoi to modern periods. The angulation of the anterior slope of the mandibular fossa in the modern period was smaller than that in other periods. CONCLUSION: The morphology of the mandibular fossa was shown to have changed and asymmetry has increased from the Yayoi to modern periods. It can be speculated that this change in morphology of the mandibular fossa in the modern period is the result of an increase of TMD.

Cephalometry↗
PubMed2000

Objective evaluation of the morphology of human epididymal sperm heads.

Spermatozoa were obtained from nine epididymal regions of six epididymides taken from five men undergoing castration for prostatic carcinoma (53-76 years) and from one man with testicular cancer (38 years). Spermatozoa were obtained by mincing tissue in phosphate-buffered saline, making air dried smears and staining with Hemacolor. The percentage of sperm heads categorised subjectively as normal (of uniform shape) or otherwise was calculated for each region. This confirmed that grossly swollen sperm heads (previously shown to be artefacts) were only present in proximal regions of the duct. A computer-aided sperm morphology analyser (Sperm Class Analyzer(R)) was used to provide objective measurements of sperm head area, perimeter, length and width of the uniform sperm heads and revealed that there was a gradual and statistically significant decline in sperm head size upon maturation, as occurs in other species. There was no significant difference between the morphometric parameters of spermatozoa obtained from the distal cauda epididymis and those obtained from the ejaculates of young normozoospermic patients.

Adult↗