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PubMed2005

MRI diffusion coefficients in spinal cord correlate with axon morphometry.

Following spinal cord injury, diffusion MRI (DWI) has been shown to detect injury and functionally significant neuroprotection following treatment that otherwise would go undetected with conventional MRI. The underlying histologic correlates to directional apparent diffusion coefficients (ADC) obtained with DWI have not been determined, however, and we address this issue by directly correlating ADC values with corresponding axon morphometry in the normal rat cervical spinal cord. ADC values transverse (perpendicular) and longitudinal (parallel) to axons both correlate with axon counts, however each directional ADC reflects distinct histologic parameters. DWI may therefore be capable of providing specific histologic data regarding the integrity of white matter.

Animals↗

PubMed1994

Thromboxane and pulmonary morphometry in the development of the pulmonary hypertensive response to group B streptococcus.

OBJECTIVE: To clarify the mechanism of the development of a severe pulmonary hypertensive response to group B streptococcus. DESIGN: Prospective, randomized controlled trial. SUBJECTS: Twelve chronically instrumented and six age-matched uninstrumented newborn piglets. INTERVENTIONS: Six animals received eight injections of group B streptococcus over an 11-day period (control group). Six additional animals (pretreatment group) were given 3 mg/kg of dazmegrel, a thromboxane synthase blocking agent, before each dose of group B streptococcus to prevent the pulmonary hypertensive response and to control for any secondary arterial remodeling. MEASUREMENTS AND MAIN RESULTS: Hemodynamic measurements, pulmonary arterial morphometry, and thromboxane concentrations were examined in the instrumented animals. Lungs from the uninstrumented piglets were examined to determine morphometric norms for this population. The animals given only group B streptococcus developed a significant pulmonary hypertensive response after five daily doses (+6.8 +/- 2.0 [SEM] mm Hg, p < .05) which became pronounced after eight doses (+13.2 +/- 1.0 mm Hg). Pulmonary hypertension was not observed in the pretreatment group when dazmegrel was given; however, on the final day in this group, dazmegrel was withheld before group B streptococcus dosing and a significant pulmonary hypertensive response was observed (+20 +/- 1.6 mm Hg). The medial thickness of pulmonary arteries was not different between the two groups nor when compared with that of six normal, uninstrumented animals. Plasma thromboxane B2 concentrations were determined from blood samples taken before and after group B streptococcus infusion at the first, seventh and eighth (final) dosing. Thromboxane concentrations increased significantly on days 7 and 8 in the control group (578 +/- 312 to 752 +/- 372 pg/mL, 638 +/- 201 to 1462 +/- 295 pg/mL, respectively) and on day 8 in the pretreatment group (545 +/- 160 to 705 +/- 187 pg/mL). CONCLUSIONS: We conclude that the development of potentiated pulmonary hypertension is not due to pulmonary arterial remodeling, but is associated with increased thromboxane production.

Analysis of Variance↗

PubMed1990

Prognostic significance of tumor cell morphometry, histopathology, and clinical parameters in advanced ovarian carcinoma.

The prognostic value of clinicopathologic data and tumor cell morphometry was assessed in 49 consecutive patients with advanced epithelial ovarian carcinoma (Stage III-IV as defined by the International Federation of Gynaecologists and Obstetricians [FIGO]). Single-variant analysis proved that nuclear area at the 10th, 50th, and 90th percentiles and nuclear density were the strongest prognostic factors. To assess difference in prognostic influence between morphometric and clinicopathologic factors, Cox regression analysis was carried out and revealed nuclear density and age as prognostically significant (p less than 0.0003 and p less than 0.0004, respectively). Choice of chemotherapy, FIGO stage, histologic grade, and mitotic activity index (MAI) were not of additional prognostic importance. Objective measurement of morphometric factors is simple, highly reproducible, and adequate for routine work and promises to be of clinical value in therapeutic decision-making in advanced ovarian carcinoma.

Adult↗

PubMed1983

Lumbar vertebral canal morphometry for computerised tomography in spinal stenosis.

Computerised tomography is described in recent literature as a sophisticated but noninvasive technique with a particularly appropriate application in the discovery of space-occupying lesions in the lumbar vertebral canal and nerve root tunnels. Although the spinal stenosis syndrome must remain a clinical diagnosis in the first instance, computerised tomography is expected to play an increasing role in confirming the presumptive diagnosis of developmental or degenerative spinal stenosis, and in confirming the presence of a trefoil configuration or narrow lateral recess. However, the diagnosis of spinal stenosis on computerised tomography is impossible unless dimensions can be compared with established ranges of normal. The morphometry of a large sample of human skeletons of both sexes, in two race groups, and for each of the five lumbar vertebral levels, is intended to provide this information.

Ethnicity↗

PubMed1997

The effect of pedicle morphometry on pedicle screw loading. A synthetic model.

STUDY DESIGN: Static nondestructive bending analysis of pedicle screws inserted into vertebral analogues was conducted. Pedicle screw bending load was studied as a function of pedicle morphometry. OBJECTIVES: To determine how sagittal bending moment in pedicle screws is affected by changes in pedicle height, length, and width. BACKGROUND DATA: An unexpectedly high rate of clinical failure has been observed in pedicle screws used in short-segment instrumentation for axially unstable fractures. The majority of screws fail in sagittal bending within the pedicle. To date, little is known of the exogenous factors that affect in situ loads incurred by pedicle screws. METHODS: Synthetic vertebral analogues were fabricated, varying pedicle height, length, or width independently. Pedicle screws internally instrumented with strain gages were used as load transducers to determine screw bending moments within the pedicle and body of the analogue. Analogues were loaded in compression to simulate loading of an unstable burst fracture. RESULTS: Screw bending moments within the pedicle increased incrementally with increasing pedicle length, rising 30% as length increased from 8.0 mm to 12.0 mm. Screw moment increased 20% when pedicle height dropped below 15.0 mm, consistent with a threshold effect. Changes in pedicle width did not affect screw loads within the pedicle. CONCLUSIONS: In situ pedicle screw loads increased significantly as pedicle length increased and as pedicle height decreased. Pedicle screws instrumented internally with strain gages are an effective research instrument allowing measurement of in situ loading along the axis of the screw.

Biomechanical Phenomena↗

PubMed1997

Morphometry of human lumbar apophyseal joints. A novel technique.

STUDY DESIGN: The anatomy of cadaveric lumbar apophyseal joints was examined as part of a study of possible correlations between lumbar apophyseal morphology, arthrosis, and cartilage thickness and stiffness. OBJECTIVES: To establish the morphometry of human upper lumbar apophyseal joints using an objective technique. SUMMARY OF BACKGROUND DATA: The apophyseal joints of 30 unfixed lumbar motion segments, all from different cadavers (24 male, five female, and one unknown, mean age 35 years, range 16-78 years) were exposed by dissection and disarticulation. Twenty-five motion segments were L1-L2, three were L2-L3, and two were L3-L4. The extent of fibrillation and linear dimensions of 29 of these specimens were examined, whereas the vertebrae and joints of 22 of them (18 being L1-L2) were cast in araldite resin. METHODS: The casts of the vertebrae were sectioned cephalocaudally at 1-mm intervals. Image processing of photographic slides of the sections established the orientations and dimensions of the lumbar apophyseal joints and their shapes using Fourier analysis. RESULTS: Apophyseal joint surface area was 158 +/- 43 mm2, cephalocaudal length 15.2 +/- 2.7 mm, and straight line length between anterior and posterior borders was 13.2 +/- 1.9 mm. The joints were orientated at 62.5 +/- 11.8 degrees to the coronal plane. Average maximum depth of concavity was 1.8 +/- 0.7 mm. The posterior edges of two joint pairs twisted inward toward the midsagittal plane in a cephalocaudal direction; thus, some apophyseal joints bear part of the axial spinal load. The right inferior surfaces were more elongated cephalocaudally (but not longer) than their contralateral partners. Inferior apophyses were significantly more elongated cephalocaudally (but not longer) than their ipsilateral articulating superior surfaces. CONCLUSIONS: In theory, Fourier analysis of joint surfaces was objective, but it dictated the criterion by which joints were grouped; care must be exercised so that measurement methods do not categorize joints artificially. "Symmetry" is too subjective to be applied to contralateral apophyseal joints; correlation coefficients should be quoted for areas and orientations. The morphology of contralateral lumbar apophyseal joint pairs was significantly correlated in all respects, as was the morphology of articulating lumbar apophyseal surfaces.

Adolescent↗

PubMed1998

Influence of muscle morphometry and moment arms on the moment-generating capacity of human neck muscles.

STUDY DESIGN: The function of neck muscles was quantified by incorporating experimentally measured morphometric parameters into a three-dimensional biomechanical model. OBJECTIVE: To analyze how muscle morphometry and moment arms influence moment-generating capacity of human neck muscles in physiologic ranges of motion. SUMMARY OF BACKGROUND DATA: Previous biomechanical analyses of the head-neck system have used simplified representations of the musculoskeletal anatomy. The force- and moment-generating properties of individual neck muscles have not been reported. METHODS: A computer graphics model was developed that incorporates detailed neck muscle morphometric data into a model of cervical musculoskeletal anatomy and intervertebral kinematics. Moment arms and force-generating capacity of neck muscles were calculated for a range of head positions. RESULTS: With the head in the upright neutral position, the muscles with the largest moment arms and moment-generating capacities are sternocleidomastoid in flexion and lateral bending, semispinalis capitis and splenius capitis in extension, and trapezius in axial rotation. The moment arms of certain neck muscles (e.g., rectus capitis posterior major in axial rotation) change considerably in the physiologic range of motion. Most neck muscles maintain at least 80% of their peak force-generating capacity throughout the range of motion; however, the force-generating capacities of muscles with large moment arms and/or short fascicles (e.g., splenius capitis) vary substantially with head posture. CONCLUSION: These results quantify the contributions of individual neck muscles to moment-generating capacity and demonstrate that variations in force-generating capacity and moment arm throughout the range of motion can alter muscle moment-generating capacities.

Biomechanical Phenomena↗

PubMed2002

Comparative morphometry of L4 vertebrae: comparison of large animal models for the human lumbar spine.

STUDY DESIGN: Anatomic analysis of L4 vertebral morphometry comparing specimens harvested from humans and five common large animal species. OBJECTIVE: To compare fundamental structural similarities and differences in the vertebral bodies of commonly used experimental animals relative to human vertebrae. SUMMARY OF BACKGROUND DATA: Animal models are commonly used for assessment of spine fusion, instrumentation techniques, and vertebral bone biology. Among the animals used, the lumbar vertebrae exhibit considerable anatomic variability. The goal of this study was to determine which of the animals commonly used for spine research is best suited as an anatomic model for the human lumbar spine. METHODS: Morphometric features of the L4 vertebrae of five common research animals were compared with those of the human L4 vertebrae. Mature canines, immature pigs, mature micropigs, mature dairy goats, and mature sheep were analyzed. These species were chosen because they are commonly selected research animals, and most research facilities do not need to be modified to use them. The samples included ten L4 vertebrae of each animal species and seven human L4 vertebrae. Each specimen was meticulously cleaned of all soft tissue. The measurements were grouped into vertebral body parameters, neural canal dimensions, and pedicle and facet morphometery. The mean of each anatomic measurement was compared using a single factor analysis of variance and a Scheffe's post hoc test, with 0.05 denoting significance. RESULTS: The human vertebral body was significantly wider and deeper in the anteroposterior plane than any of the animals studied. However, the mean vertebral body height of the sheep and goat significantly exceeded that of the human specimens. The mean pedicle angle of every animal species was significantly greater than that of the human. The mean pedicle width of the micropig and goat were significantly narrower than the human pedicles, and the dog specimens lacked a definable pedicle altogether. There was no significant difference in mean pedicle width between any of the remaining species and the human specimens. Facet tropism and radius of curvature of the sheep and goat specimens differed significantly from the remaining selections. CONCLUSIONS: When posterior pedicle instrumentation is part of a testing protocol, the increased pedicle angle and lack of vertebral body depth found in all animals studied must be kept in mind. In addition, when testing interbody cages designed to stabilize the spine and promote fusion, one must be aware of the decreased vertebral body depth and width in these animals, as compared with humans. Physeal defects in the immature pig may alter specific biomechanical results during failure or fatigue testing, or in basic studies of vertebral bone material properties. In all cases, instrumentation and hardware must be sized appropriately to the selected model to provide meaningful results.

Age Factors↗

PubMed2007

Thoracic and lumbar pedicle morphometry in achondroplasia.

For safe pedicle screw insertion, knowing pedicle anatomy is essential. Pedicle morphometry in achondroplasia has not been quantitatively described. Therefore, we analyzed 302 thoracic and lumbar pedicles in 11 patients using computed tomography. Transverse endosteal diameter, screw path length, transverse angle, sagittal diameter, and sagittal angle were calculated. We analyzed for safe screw length, size, and trajectory. The data were compared with that on healthy people of different races. In patients with achondroplasia, the maximum endosteal diameter was at L5 and the minimum was at T5. Screw path length was longest at L2 and shortest at T2. Most dimensions were smaller compared with those of healthy people. Abnormal anteromedial transverse angulations were observed between T11 to L2. The maximum transverse angulations were at T2. Sagittal diameter was largest at T12 and smallest at T5. The maximum sagittal angle was seen at T2, and at L5 it was caudal. At all levels except L5, the transverse diameter is the limiting factor for screw size. Six-millimeter screws can be used at L5. Screws that are 35 mm or less are safe to use between T7 to L5. There are surgically important differences in the different angles and diameters of thoracic and lumbar pedicles of patients with achondroplasia and those of healthy people.

Achondroplasia↗

PubMed2006

Computed tomographic morphometry of thoracic pedicles: safety margin of transpedicular screw fixation in malaysian malay population.

STUDY DESIGN: A cross-sectional study of thoracic pedicle morphometry (T1-T12) of 180 Malaysian Malay patients obtained from computed tomographic scan. OBJECTIVES: To determine the safety margin in the placement of thoracic transpedicular screw in the Malay population. SUMMARY OF THE BACKGROUND DATA: Previous studies have shown a significantly smaller thoracic pedicular parameters in Asians compared with whites. The safety margin in the placement of thoracic transpedicular screw in our population therefore needs to be defined. METHODS: T1-T12 vertebral pedicles were studied in 180 Malay ethnic patients (age range, 18-80 years). The following parameters were studied: transverse outer pedicle diameter, transverse inner pedicle diameter, transverse pedicle angle, chord length, pedicle length, and pedicle cortical thickness. The data obtained were statistically analyzed using Student's t test and ANOVA test. RESULTS: Female patients have significantly smaller dimensions in most of the parameters measured compared with male patients. However, no significant difference was found between age groups. Transverse outer pedicle diameter were widest at T1 (male, 8.42 mm; female, 7.56 mm) and narrowest at T4 (male, 4.56 mm; female, 3.95 mm). Pedicle diameters of less than 5.5 mm were commonly seen at T4 followed by T5, T6, T7, T8, and T9. A significant percentage of patients have an outer diameter of less than 4.5 mm from T4-T7. The medial cortices were 50% thicker than the lateral cortices at most levels. Chord lengths were maximum at T8 and minimum at T1. Transverse pedicle angle were widest at T1 and less than 5 degrees from T7-T12. CONCLUSIONS: The results suggest that the current pedicle screw system is not suitable for the majority of Malay population, especially at midthoracic level. The smaller pedicle measurements in Malays may be attributed to their shorter body built compared with whites.

Adult↗

PubMed2006

A voxel-based morphometry study of gray matter in parents of children with autism.

Previous structural imaging studies of autistic individuals have identified gray matter abnormalities. It remains unclear, however, which abnormalities contribute to the etiology of autism and, among these abnormalities, which reflect genetic factors. Using voxel-based morphometry, we compared regional gray matter volume in 23 parents of autistic children to an age and sex-matched control sample. We identified relative local gray matter volume increases and decreases in the parent group that are consistent with previous research with autistic individuals. Further, differences were identified in regions that are functionally associated with social-cognitive and motor processes that are impaired in autism. This investigation constitutes the first whole-brain study of regional brain volume in the parents of autistic children, and suggests that a number of structural changes observed in autism may be familial.

Adult↗

PubMedDate not supplied

Ultrasonographic hip morphometry in infants.

Ultrasonographic study of 463 normal children (926 hips) from birth to 6 months of age with equal sex distribution was performed. Hip morphometry, including Graf's alpha and beta angles. Morin's head coverage percentage, and head size were measured. Using the same technique, a group of 52 babies was measured longitudinally from birth to 6 months of age, with three measurements taken for each hip for a total of 312 measurements. Results showed that the boys had a consistently higher alpha angle, a lower beta angle, better head coverage, and larger head size through the 6 months. Differences between the right and left hips were only noted in the beta angle. The containment of the hip was found to increase rapidly in the first 4 months. Comparing data from the longitudinal versus the cross-sectional group, no statistically significant differences were detectable in all the parameters measured. Intraobserver variations were found to be best with alpha angle measurements, with a standard deviation of 3.22 degrees.

Age Distribution↗

PubMed2003

Voxel-guided morphometry ("VGM") and application to stroke.

Monitoring of cerebral diseases associated with a change of morphology (e.g., stroke) requires unprecedented accuracy for quantification of its morphological progression for each voxel. The purpose of this paper is to provide a technique [voxel-guided morphometry (VGM)] to quantify macroscopic anatomical differences. VGM consists of four steps: 1) coarse linear alignment by the extended principle axes theory (ePAT) generalized to affine movements; 2) a cross-correlation-based technique using a matrix-norm for fine linear alignment; 3) the applied high-dimensional multiresolution full multigrid method determines the nonlinear deformations, thereby achieving a complete exploitation of information and effective processing. The method measures a gray-value-guided movement of each voxel from source to target. The resulting high-dimensional deformation field is further processed by 4) determination of volume alterations for each voxel. Furthermore, the effect of linear registration errors on final morphometric measurements is discussed and the conditions for a bijective correspondence of voxels assuming small alterations are derived. To illustrate the technique the changing morphology of different subjects suffering from cerebral infarction is presented by using commonly available T1-weighted magnetic resonance volumes. VGM visualizes that ischemic as well as remote regions are affected by stroke.

Algorithms↗

PubMed2006

Brain T1 intensity changes after levodopa administration in healthy subjects: a voxel-based morphometry study.

AIM: To test T1 intensity variations induced by levodopa administration in the regional fixation area in the human brain. METHOD: Using non-invasive magnetic resonance imaging (MRI) technique [T1-weighted sequence MPRAGE; TE/TR/TI = 5/25/800 ms; impulsion angle = 15 degrees; field of view = 256 x 230 x 180 mm3; acquisition matrix = 256 x 192 x 104; reconstruction matrix = 256 x 256 x 128), we tested changes in the T1 MRI signal intensity resulting in changes in the grey matter automatic classification after administration of a single dose of 100 mg of levodopa by a voxel-based morphometry method (VBM) in 12 healthy subjects. RESULTS: The VBM analysis demonstrated an increased number of voxels attributed to grey matter after levodopa administration in an anatomical cluster which included substantia nigra, tegmental ventral area and subthalamic nucleus bilaterally, the principal origin and first relay nuclei of projections in brain dopaminergic systems (t = 8.61; corrected for all grey matter volume P < 0.001). CONCLUSION: Our results suggest that levodopa administration could induce an MRI T1 signal intensity variation that is not evident to the naked eye, but is detectable by measuring local signal intensities. Possible clinical applications are discussed.

Aged↗

PubMed1981

The relevance of morphometry in the differential diagnosis of cutaneous T cell lymphomas.

Morphometric analysis of lymphoid cells in the skin was used to differentiate between cutaneous T cell lymphomas (CTCL), i.e. mycosis fungoides (MF) and Sézary syndrome (SS), and chronic benign skin diseases. In electronmicrographs of the skin lesions from twenty patients with CTCL (group I), fourteen patients with chronic benign skin diseases (group II) and twenty-nine patients suspected of CTCL (group III), the degree of nuclear indentation of lymphoid cells, expressed as the nuclear contour index (NCI), was measured. Analysis of the NCI histograms of the infiltrating cells of group I and group II permitted us to derive classification criteria for allocating all patients correctly with a high probability (greater than or equal to 95%) in the appropriate group. Only one case was classified with a low probability (71%). The classification criteria are based on the presence of cerebriform mononuclear cells (CMC) with highly indented nuclei (NCI greater than or equal to 11.5) and the frequency distribution of CMC in the skin infiltrates expressed as the 25th and the 70th percentiles of the NCI histograms (P25 + P70). When these criteria were tested on twenty-nine patients suspected of CTCL, twenty cases were classified as malignant, nine as benign. During the follow-up period, out of the twenty patients classified as malignant, seventeen patients appeared to have or develop MF, whereas two patients had lymphomatoid papulosis and one patient is still suspected of MF. Of the nine patients classified as benign, eight patients were proven to have benign skin diseases whereas one developed MF in the follow-up period of up to 4 years. The classification results based on morphometry proved to be more sensitive than those based on DNA cytophotometry. It is concluded that morphometric analysis of lymphoid cells in the skin is of diagnostic relevance in the differential diagnosis of CTCL.

Adolescent↗

PubMed2006

Morphometry and digital AgNOR analysis in cytological imprints of benign, borderline and malignant serous ovarian tumours.

AIM: The aim of the study was to determine values of a quantitative morphometry analysis of nuclear characteristics and argyrophilic nucleolar organizer regions (AgNORs) in differential cytodiagnosis of benign, atypically proliferating (borderline) and malignant serous ovarian tumours. METHODS: Cytological imprints of benign (n = 20), borderline (n = 19) and malignant (n = 20) ovarian serous tumours were analysed. A computerized, digital analysis was used to determine morphometric nuclear features, the number and characteristics of single AgNORs, cluster AgNORs, total AgNOR and AgNOR area/nucleus (relative area) ratio. According to their size AgNORs were classified in three categories. A one-way variance analysis and post hoc test (Scheffé) were used for statistical analysis. RESULTS: The morphometric nuclear analysis showed that benign, borderline and malignant serous ovarian tumours are statistically different (P < 0.001) according to the area and outline, the values being highest in malignant tumours and lowest in the borderline group. Digital analysis of AgNORs in benign, borderline and malignant groups showed that the total AgNOR number increases with progression of the lesion (meaning tumour malignancy) significantly (P < 0.001) between benign and malignant as well as between borderline and malignant serous ovarian tumours (P < 0.001). The progression of the lesion malignancy was accompanied by a significant (P < 0.001) progressive increase of the total and relative AgNOR area per nucleus. The AgNOR size increases from benign to malignant tumours and a statistically significant difference (P < 0.001) was observed in all three groups regarding small and large AgNORs. CONCLUSION: Combining different markers of morphometric nuclear characteristics and AgNOR values could improve differential cytodiagnosis of benign, borderline and malignant serous ovarian tumours.

Cystadenocarcinoma, Serous↗

PubMed1981

Glomerular morphometry I: nephrotic syndrome in childhood.

Glomerular morphometry was performed on needle biopsy specimens from 53 children with the nephrotic syndrome with minimal change (MC), focal global glomerulosclerosis (FGS) and segmental glomerulosclerosis (SGS). There were significantly fewer epithelial cells and more mesangial cells in SGS compared with MC and FGS. The number of epithelial cells decreased with age in MC and FGS, but was constantly low at all ages in SGS. There were no significant differences in differential cellularity between MC, with or without focal glomerular obsolescence or focal tubular atrophy, and FGS. Glomerular diameter increased with age in MC and FGS, but not in SGS. These findings support the view that SGS is a distinct entity rather than a variant of MC.

Age Factors↗

PubMed1981

The prognostic significance of morphometry in T1 bladder tumours.

Only 3% of patients with T1 bladder tumours die of bladder carcinoma within 5 years (Williams, Hammonds & Saunders 1977), therefore these patients are initially treated conservatively. There would however be benefits from being able to predict which patients should be treated more aggressively. Morphometry was applied to quantitate characteristic microscopical features of the removed T1 tumours in 16 patients who had survived for five years and in seven patients dead from the tumour, in order to evaluate the prognostic value of this method. The measurements of nuclear and cytoplasmic areas were made on routine H & E sections with a graphic tablet (ASM, Leitz). Statistical analysis of the obtained data revealed that there were significant differences between the two groups. It indicated that morphometric parameters of T1 bladder tumours can have prognostic as well as therapeutic significance which will be further tested in a prospective study.

Aged↗