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At least 937 records · Page 52Linked to original sources
PubMed1998

Coronary sinus pacing initiates counterclockwise atrial flutter while pacing from the low lateral right atrium initiates clockwise atrial flutter. Analysis of episodes of direct initiation of atrial flutter.

INTRODUCTION: Rapid atrial pacing in sinus rhythm may directly induce atrial flutter without provoking intervening atrial fibrillation, or initiate atrial flutter indirectly, by a conversion from an episode of transient atrial fibrillation provoked by rapid atrial pacing. The present study was performed to examine whether or not the direct induction of clockwise or counterclockwise atrial flutter was pacing-site (right or left atrium) dependent. METHODS AND RESULTS: We analyzed the mode of direct induction of atrial flutter by rapid atrial pacing. In 46 patients with a history of atrial flutter, rapid atrial pacing with 3 to 20 stimuli (cycle length = 500 - 170 ms) was performed in sinus rhythm to induce atrial flutter from 3 atrial sites, including the high right atrium, the low lateral right atrium, and the proximal coronary sinus, while recording multiple intracardiac electrograms of the atria. Direct induction of atrial flutter by rapid atrial pacing was a rare phenomenon and was documented only 22 times in 15 patients: 3, 11, and 8 times during stimulation, respectively, from the high right atrium, low lateral right atrium, and the proximal coronary sinus. Counterclockwise atrial flutter (12 times) was more frequently induced with stimulation from the proximal coronary sinus than from the low lateral right atrium (8 vs 1, P = .0001); clockwise atrial flutter (10 times) was induced exclusively from the low lateral right atrium (P = .0001 for low lateral right atrium vs proximal coronary sinus, P = .011 for low lateral right atrium vs high right atrium). CONCLUSIONS: Direct induction of either counterclockwise or clockwise atrial flutter was definitively pacing-site dependent; low lateral right atrial pacing induced clockwise, while proximal coronary sinus pacing induced counterclockwise atrial flutter. Anatomic correlation between the flutter circuit and the atrial pacing site may play an important role in the inducibility of counterclockwise or clockwise atrial flutter.

Adult↗
PubMed1996

Extrinsic and intrinsic connections of the cat's lateral suprasylvian visual area.

The lateral suprasylvian visual area (LS) is known to have numerous interconnections with visual cortical areas as well as with subcortical structures implicated in visually-guided behaviors. In contrast, little data is available regarding connections within the LS itself. In order to obtain information about intra-areal connections and to re-investigate LS connectivity with various cortical and subcortical areas, the traces (biocytin or WGA-HRP) was injected into various loci along the medial and lateral banks of the LS. The anterograde tracer, biocytin injections into both medial and lateral bank produced label contained within the respective bank that extended rostrally and caudally from the infection site. In addition, following medical bank injections, considerable label was distributed throughout the fundus and, to a lesser extent, in the lateral bank. In contrast, no label could be detected in the medial bank after lateral bank injections, and, although label was observed in the fundus, it was restricted to the most lateral aspects. Moderate labeling could be observed in the medial bank following the tracer injection into the most rostral aspect of the lateral bank. It is likely that input derived from various visual cortical areas which project to the medial bank of the LS has access to this intra-areal circuitry. This may provide a route by which visual cortical information can be relayed to other cortical and subcortical structures involved in visually-guided behaviors such as the anterior ectosylvian visual cortex, striatum, and the deep layers of the superior colliculus, despite the fact that these structures themselves do not receive substantial direct projections from the visual cortical areas that are associated with the medial bank. Examination of the laminar location of the cells-of-origin of striate and extrastriate projections to LS using retrograde trace, WGA-HRP, revealed that the supragranular laminae of areas 17, 18 and 19 were the source of LS afferents whereas afferents from the other cortical areas (e.g., 20a, 20b, 21a, 21b, 7 and anterior ectosylvian visual area) were from both supra- and infragranular laminae. In addition, all LS subregions received intra-areal afferent projections from all LS cortical laminae. Thus, although rather clear hierarchical relationship between LS and visual cortical areas appears to exist, the interconnections among LS subregions provide no clear evidence of simple hierarchical relationships between regions LS or may have feed-forward and feed-back pathways.

Animals↗
PubMed1993

Effect of three obturation techniques on the filling of lateral canals and the main canal.

The three-dimensional obturation of the root canal system is widely accepted as a key factor for successful endodontic therapy. The purpose of this study was to evaluate the obturation of lateral canals and the main canal using three gutta-percha sealer techniques: cold lateral condensation, warm lateral condensation, and warm vertical condensation. Sixty epoxied blocks with five lateral canals placed at varying angles from the main canal were used. Each experimental group was treated by a board-certified endodontist with training and clinical experience in that obturation technique. There was no statistically significant difference (p < 0.05) between the obturation techniques in the ratio of the void area to the gutta-percha-plus-sealer area for the main canal. There was significantly (p < 0.001) more sealer in the lateral canals for the two lateral condensation techniques. The warm obturation techniques had significantly (p < 0.001) more gutta-percha in the lateral canals.

Analysis of Variance↗
PubMed1993

Alternating skew on lateral gaze. Neuroanatomic pathway and relationship to superior oblique overaction.

BACKGROUND: Previous studies of patients with heterogeneous, often diffuse neurologic disorders concluded that the neurologic substrate for alternating skew on lateral gaze may be localized at the level of the brain stem tegmentum or the cervico-medullary junction, or both. The localized nature of brain tumors offers an opportunity to further investigate the anatomic localization for this as well as other conditions. METHODS: To test the hypothesis that cervico-medullary and cerebellar lesions are responsible for alternating skew on lateral gaze, the authors investigated a series of 50 children with brain tumors, 39 of whom showed neuro-ophthalmologic abnormalities on clinical testing. Seven children had alternating skew on lateral gaze. RESULTS: All seven children with alternating skew on lateral gaze showed neoplastic involvement at the level of the cervico-medullary junction and/or the cerebellum on critical analysis of neuro-imaging studies. CONCLUSION: The authors conclude that the neuroanatomic substrate for alternating skew on lateral gaze is localized at the level of the cervico-medullary junction and/or the cerebellum. Knowing that (1) alternating skew on lateral gaze closely mimics superior oblique overaction clinically, (2) superior oblique overaction is frequently found in patients with myelomeningocele, and (3) myelomeningocele is uniformly associated with Arnold-Chiari type II which includes cerebellar and cervico-medullary region abnormalities, the authors propose that alternating skew on lateral gaze and superior oblique overaction associated with myelomeningocele have similar neuroanatomic pathways.

Adolescent↗
PubMed2001

Spatiotemporal maturation of the central and lateral N1 components to tones.

This paper examines maturational changes in the spatiotemporal features of central and lateral N1 components of the auditory evoked potentials (AEPs) to tone stimuli presented with a long stimulus onset asyncrony (SOA; 4200 ms) using the scalp current density (SCD) technique. A group of typically developing children ranging from 6 to 12 years of age and a group of adults were studied. Recently studies have begun to explore the topography of these components in children. These studies, however, often used rapidly presented stimuli and did not elicit observable central N1s in the younger children. Our stimuli elicited both central and lateral N1s. Peak latencies of both components decreased with age. Peak amplitude also decreased with age for the lateral N1 but not for the central N1. Consequently, the difference between the lateral N1 and the central N1 amplitudes (or the ratio of lateral N1 amplitude to central N1 amplitude) also decreased with age, dramatically altering the morphology of the elicited AEP waveforms. Topography of the lateral N1 did not change with age. The location of maximal activation for the central N1 appeared to move more medially with age but this 'apparent' movement is probably due to the decreasing impact of the partially overlapping lateral N1 component whose amplitude is significantly smaller in adults than in children.

Acoustic Stimulation↗
PubMed2000

Direct projection from the cardiovascular control region of the cerebellar cortex, the lateral nodulus-uvula, to the brainstem in rabbits.

In decerebrate unanesthetized rabbits, electrical stimulation of the lateral nodulus-uvula in the cerebellar vermal cortex evoked an increase in renal sympathetic nerve activity, an increase in blood pressure and a decrease in renal arterial blood flow, which were all in contrast to the effects reported previously in the anesthetized rabbits. In order to identify the pathway mediating these responses, we investigated the Purkinje cell projection from the lateral nodulus-uvula using both anterograde (biotinylated dextran amine, BDA) and retrograde (horseradish peroxidase, HRP) tracing methods in rabbits. When BDA was iontophoretically injected into the lateral nodulus-uvula, labeled Purkinje cell axons were found within and around the superior and inferior cerebellar peduncles (SCP and ICP, respectively). Furthermore, terminal-like fields were found in the dentate and vestibular nuclei as reported in previous studies. However, the terminal-like patterns that we observed in the parabrachial nucleus (PB) in the rabbit have not been reported yet. When HRP was microinjected into the lateral PB, retrogradely labeled Purkinje cells were found in the lateral nodulus-uvula. These results indicate that Purkinje cells in the lateral nodulus-uvula project into the vestibular nuclei via the ICP and to the lateral PB via the SCP. We suggest that these two pathways mediating cardiovascular responses have different sensitivities to anesthetics.

Animals↗
PubMed1997

Precision measurement of disc height, vertebral height and sagittal plane displacement from lateral radiographic views of the lumbar spine.

OBJECTIVE.: To compile a database of disc height, vertebral height and sagittal plane displacement from lateral radiographic views of the lumbar spine, valid for male and female subjects in the age range 16-57 years. The protocols used to measure these parameters compensate for distortion in central projection, off-centre position, axial rotation and lateral tilt of the spine as well as for variation in radiographic magnification and stature. STUDY DESIGN.: The study comprised designing and testing of measurement protocols, together with subsequent data collection from archive radiographs. BACKGROUND.: Attempts to quantify primary mechanical damage to lumbar vertebrae and discs have been limited due to imprecision when measuring disc height, vertebral height and sagittal plane displacement. Age-related, normative values for these parameters were not previously available. Consequently, important issues like the effectiveness of past and present guidelines for safe manual handling with respect to prevention of overload injuries could not be resolved and judgement on pathological alterations in the morphology of the individual lumbar spine could only be performed in a qualitative, subjective manner. METHODS.: Based on the analysis of vertebral contours in the lateral radiographic image of the lumbar spine, new protocols for measuring disc height, vertebral height and sagittal plane displacement were developed. The measured data are virtually independent of distortion, axial rotation and lateral tilt. Furthermore, description of height and displacement using dimensionless parameters guarantees independence of radiographic magnification and stature. Subjective influence in the measurement procedure was minimized by automatic computation of contour-landmarks and derived parameters. Measurement errors were assessed from sets of radiographs of spine specimens and serial flexion-extension radiographs; interobserver and intraobserver errors were assessed from repeated measurements of lateral views. For compilation of a database, measurements were performed of a set of 892 lateral views of the lumbar spine of male and female subjects between 16 and 57 years of age. Data from pathologically deformed vertebrae or discs, or from motion segments exhibiting spondylolisthesis or retrolisthesis were excluded by normal radiological inspection; data from spines showing normal, age-related degenerative changes were included. RESULTS.: The new protocols allow height and displacement of lumbar vertebrae as well as height of lumbar discs to be measured for all motion segments on a lateral view, rather than just those vertebrae or discs close to the central beam, to facilitate recognition of localized abnormalities. Since the results are independent of exposure geometry, retrospective investigations are feasible. The relative measurement error in vertebral height amounts to 2.2%; for a vertebra of 30 mm height this corresponds to an error of approximately 0.7 mm. The error in sagittal plane displacement amounts to 0.015 (measured in units of mean vertebral depth); for a vertebra of 35 mm depth this corresponds to an error of 0.5 mm. The relative error in disc height amounts to 4.15%; for a disc of 10 mm height this corresponds to an error of approximately 0.5 mm. For both genders, the database contains age-dependent, normative values of disc height, vertebral height and sagittal plane displacement. In addition, the database describes intersegmental shape correlation, i.e. the relation between height of neighbouring discs and between height as well as displacement of neighbouring vertebrae. On average, height of lumbar vertebrae is larger in females than in males; height of lumbar discs is larger in males than in females and shows a minute dependence on age in males; in both genders, sagittal plane displacement increases, but only by a small amount, with age. CONCLUSIONS.: The new measurement protocols for disc height, vertebral height and sagittal plane displacement, together with the database of normative age-related values, permit quantitative assessment of the prevalence of pathological morphological changes in the human lumbar spine. The new method and the database will serve to explore the effect of potentially detrimental influences such as high spinal loading and to provide quantitative documentation of existing injury to vertebrae and discs in individual cases.

Journal Article↗
PubMed1997

Measurement of plantar pressure distribution during gait for diagnosis of functional lateral ankle instability.

INTRODUCTION:: Chronic functional instability of the lateral ankle may be difficult to distinguish from mechanical instability when radiological stress tests reveal only small ligamentous defects. For decision making whether to surgically reconstruct the ligaments or not, it can be helpful to use additional information on joint and foot function. Therefore, the aim of a prospective study of patients with longstanding chronic ankle instability was to demonstrate that the dynamic measurement of plantar pressure distribution can identify patients with functional ankle instability. [Table: see text] MATERIALS AND METHODS:: Sixty five patients (mean age 24 (4.6 years)) were included. After clinical examination and radiological stress views, plantar pressure patterns were measured during gait using a capacitive platform, the EMED-SF 2-system. Five trials of each foot were documented and the maximum impulses in eight points of the foot (central heel, lateral and medial heel, midfoot, 1st, 2nd, 5th metatarsal head and hallux) were calculated intraindividually and compared with a group of 100 healthy subjects. The medio-lateral loading factor (MLF) as the quotient of the medial and lateral relative impulses indicated the tendency to walk on the lateral edge of the foot. RESULTS:: Based on clinical criteria alone, two comparable groups of patients were separated, 35 with functional instability and 30 with mechanical instability. After collective analyses of the results, the patients with functional instability showed a significantly increased lateral loading of the unstable foot (p=0 0 1), whereas the mechanically unstable group tended to walk more on the medial side of the unstable foot (Table 1). DISCUSSION:: Dynamic measurement of plantar pressure can identify a group of patients walking on the lateral side of the unstable foot when compared with the stable foot. This finding is explained by a deficit of peroneal strength during stance phase based on a proprioceptive defect after trauma. The new application of the EMED-system provides additional information which helps to make decisions about the individual patient with chronic instability.

Journal Article↗
PubMed1998

Quantifying lateral pelvic displacement during walking.

OBJECTIVE: The purpose of this investigation was to test a new procedure for quantifying lateral pelvic displacement during walking. DESIGN: A quasi-experimental design was used to quantify the gait of 18 unimpaired people and one person with hemiplegia. BACKGROUND: Although previous techniques provided useful information on amplitude of lateral pelvic displacement, they did not consider step-to-step variations in walking direction or enable quantification of symmetry. METHODS: Three-dimensional motion analysis was used to collect the coordinates of light-reflective markers placed on the scarum and heels of each subject. Subjects performed one 10 m overground walk at their preferred speed. Amplitude and symmetry of lateral pelvic displacement were quantified relative to the step-to-step variation in the path of motion (base of support). RESULTS: The mean amplitude of lateral pelvic displacement for the unimpaired group was 40.8 mm, and symmetry was 3.1 mm. The amplitude of lateral pelvic displacement for the hemiplegic person was 88.4 mm. Symmetry was 30.9 mm, with deviation toward the non-paretic side. CONCLUSION: The new procedure provided information on the amplitude and symmetry of lateral pelvic displacement in unimpaired adults and was sensitive to deviations of a person with a walking abnormality. RELEVANCE: Treatment of atypical lateral pelvic displacement is frequently an aim of stroke rehabilitation. Therefore, it is important to have objective, accurate methods of quantification.

Journal Article↗
PubMed2003

Genetic analysis of the gravitropic set-point angle in lateral roots of Arabidopsis.

Research on gravity responses in plants has mostly focused on primary roots and shoots, which typically orient to a vertical orientation. However, the distribution of lateral organs and their characteristically non-vertical growth orientation are critical for the determination of plant form. For example, in Arabidopsis, when lateral roots emerge from the primary root, they grow at a nearly horizontal orientation. As they elongate, the roots slowly curve until they eventually reach a vertical orientation. The regulation of this lateral root orientation is an important component affecting overall root system architecture. We found that this change in orientation is not simply due to the onset of gravitropic competence, as non-vertical lateral roots are capable of both positive and negative gravitropism. Thus, the horizontal growth of new lateral roots appears to be determined by what is called the gravitropic set-point angle (GSA). This developmental control of the GSA of lateral roots in Arabidopsis provides a useful system for investigating the components involved in regulating gravitropic responses. Using this system, we have identified several Arabidopsis mutants that have altered lateral root orientations but maintain normal primary root orientation.

Arabidopsis↗
PubMed2001

Palpation of the lateral pterygoid region in TMD--where is the evidence?

OBJECTIVE: Palpation of the lower head of the lateral pterygoid muscle is included in many study protocols and examination schemes of the masticatory system. The aim of this investigation was to search the medical/dental literature to find evidence for the validity and reliability of this diagnostic procedure. METHODS: A systematic search was carried out using different electronic databases (Medline Ovid, PubMed, Cochrane Library, Embase, Current Contents Connect, Science Citation Index, Web of Science, Japana Centra Revuo Medicina), supplemented by handsearch in selected journals and by examination of the bibliographies of the identified articles. RESULTS VALIDITY: As far as the palpability of the inferior head of the lateral pterygoid muscle is concerned, five publications representing four studies could be identified. According to these investigations, the lateral pterygoid muscle is practically inaccessible for intraoral palpation due to topographical and anatomical reasons. Other anatomical structures, such as the superficial head of the medial pterygoid muscle, may be palpated instead in this region. Reliability: Determination of the palpability of the lateral pterygoid muscle is characterized by poor interexaminer agreement. Studies investigating the presence of pain in response to palpation of the lateral pterygoid area revealed a moderate intra- and interindividual reliability. Because of the tenderness of the lateral pterygoid region even among healthy subjects, positive findings may lead to wrong conclusions with regard to the need of treatment. CONCLUSIONS: Considering the lack of validity and reliability associated with the palpation of the lateral pterygoid area, this diagnostic procedure should be discarded.

Databases as Topic↗
PubMed1999

The location of muscarinic type 2 receptors within the synaptic circuitry of the cat lateral posterior nucleus.

The ultrastructural distribution of the muscarinic type 2 acetylcholine receptor (M2) was examined in the lateral division of the lateral posterior (LP) nucleus of the cat thalamus, using immunocytochemistry. Postembedding immunocytochemical staining for gamma-aminobutyric acid (GABA) further characterized M2 stained profiles. M2 receptors were predominately found on small caliber (presumably distal) dendritic arbors of thalamocortical cells and interneurons in the lateral LP nucleus. While glomeruli were not abundant in the lateral LP nucleus, occasionally they contained dendritic terminals of interneurons (F2 profiles) stained for M2 receptors. Some GABAergic terminals throughout the neuropil also stained for M2 receptors. The location of M2 receptors correlates well with the cholinergic innervation of the lateral LP nucleus and suggests that muscarinic modulation of visual signals differs in the lateral LP nucleus as compared with the lateral geniculate and pulvinar nuclei.

Animals↗
PubMed2004

Dopaminergic olivocochlear neurons originate in the high frequency region of the lateral superior olive of guinea pigs.

Dopaminergic neurons are known to exist within the lateral superior olive (LSO). The LSO is the nucleus of origin of the lateral olivocochlear neurons, which project to the cochlea and synapse onto the primary afferents contacting the inner hair cells. We investigated whether the dopaminergic neurons in the LSO are part of the lateral olivocochlear neuron population. We combined intracochlear injections of a fluorescent retrograde tracer with immunofluorescent staining of tyrosine hydroxylase (TH). TH was used as a marker for dopaminergic neurons. After the injection with retrograde tracer most of the TH-labelled neurons in the LSO also contained the tracer, which directly demonstrates for the first time that the TH-labelled, dopaminergic neurons in the LSO are lateral olivocochlear neurons. TH-labelled neurons were not equally distributed over the LSO as is observed for the lateral olivocochlear neurons in general. TH-labelled neurons were almost exclusively seen in the medial, high frequency, limb of the LSO. Since the projection of the lateral olivocochlear neurons to the cochlea is known to be tonotopic, we investigated the TH-labelling in the cochlea as well. We found that the staining pattern of TH in the cochlea is in broad agreement with the distribution of TH-labelling in the LSO. Cochlear sections showed dense labelling in the basal and second, high frequency, turns and decreasing intensity of staining in the third turn, while the extreme apical, low frequency, turn was almost devoid of any positive TH-labelling. These observations imply that the dopaminergic neurons of the lateral olivocochlear system may play a role in the selective suppression of the high frequency fibers of the auditory system.

Animals↗
PubMed1992

Lateral patellar release in knee arthroplasty. Effect on wound healing.

A prospective study analyzing the effects of intraoperative lateral patellar release for patellar instability in total condylar knee arthroplasty demonstrated that lateral release was successful in preventing postoperative patellar instability. Division of the superolateral geniculate vessels resulted in an increased incidence of wound discoloration (P < .01) and superficial wound infection (P < .05). Perioperative transcutaneous measurement of the skin oxygen tension demonstrated an objective reduction in lateral wound edge skin viability following lateral release (P < .02). A lower threshold for performing lateral patellar release is necessary. To preserve the viability of the lateral skin edge, lateral release should be performed using the intracapsular approach with preservation of the superolateral geniculate vessels.

Adult↗
PubMed1999

Flexion-extension joint gap changes after lateral structure release for valgus deformity correction in total knee arthroplasty: a cadaveric study.

At the time of total knee arthroplasty, the surgeon generally corrects excessive valgus knee alignment to anatomic valgus through release of lateral supporting structures. This study used a cadaveric model to i) study the amount of correction achieved with each release step in 2 sequences of lateral release, ii) compare the amount of release in extension versus flexion, and iii) measure any associated rotational changes of the tibia. Six fresh-frozen cadaveric knees were used to test the amount of change into varus after sectioning the iliotibial band (ITB), the popliteus tendon (Pop), the lateral collateral ligament (LCL), and the tendon of the lateral head of the gastrocnemius (LG). This sequence was then compared with a second sequence in another 6 cadavers as follows: LCL, Pop, ITB, and LG. The amount of valgus correction was tested in 90 degrees, 45 degrees flexion, and full extension. At each flexion angle, the corresponding releases were assessed with the tibia oriented vertically under its own weight, under tibial distraction with equal support from the lateral and medial soft tissues, and under a maximal varus deforming stress. Results showed that complete lateral structure release provides limited correction into a varus direction with a balanced distracted soft tissue gap or extension space (8.9 degrees with the LG released), and the lateral aspect of the flexion gap opens more than the extension gap (8.9 degrees compared with 18.1 degrees in flexion). Early LCL release provided a more uniform release of the joint gap, and rotational changes were variable, tending toward external rotation of the tibia (6.0 degrees in full extension with release of the LCL). We suggest that when severe valgus deformities are present, the LCL should be considered first for release and the Pop and ITB be used to grade the release.

Arthroplasty, Replacement, Knee↗
PubMedDate not supplied

Reliability of a patient-rated forearm evaluation questionnaire for patients with lateral epicondylitis.

PURPOSE: To determine the reliability of a questionnaire designed to assess forearm pain and function in patients with lateral epicondylitis. METHODS: Forty-seven patients with unilateral lateral epicondylitis completed a patient-related forearm evaluation questionnaire (PRFEQ) on two occasions. Intraclass correlation coefficients (ICC 2,1), standard error of measurement (SEM), and 95% confidence intervals (CIs) were determined for the whole group and for three subgroup comparisons of male vs. female subjects, subacute vs. chronic lateral epicondylitis, and work-related vs. non-work-related lateral epicondylitis. RESULTS: The test-retest reliability for the overall PRFEQ (ICC, 0.89), and its pain (ICC, 0.89) and function (ICC, 0.83) subscales was excellent. Test-retest reliability for patients with work-related lateral epicondylitis (ICC, 0.80) was significantly (p = 0.018) less than for patients with non-work-related lateral epicondylitis (ICC, 0.94). CONCLUSIONS: The PRFEQ can provide a simple, quick, and reliable estimate of arm pain and function in patients with lateral epicondylitis. However, large SEM and 95% CIs limit its ability to accurately predict individual scores.

Female↗
PubMed1998

Transcranial cerebral oximetry during carotid endarterectomy: agreement between frontal and lateral probe measurements as compared with an electroencephalogram.

OBJECTIVE: Transcranial cerebral oximetry, which is considered a novel technique, was evaluated during carotid endarterectomy. For practical reasons, the use of a single probe attached to the forehead and overlying the territory of the anterior cerebral artery is recommended. Other monitoring systems (transcranial Doppler, electroencephalograms (EEG)) focus more on the territory of the middle cerebral artery. The aim of this study was to evaluate whether a probe in the frontal area is as representative for monitoring cerebral ischaemia during carotid cross-clamping as a probe in the lateral area. DESIGN: Clinical prospective study. MATERIALS: Sixty patients who underwent carotid endarterectomy were studied with continuous and simultaneous EEG and transcranial cerebral oximetry. Forty-three patients (72%) simultaneously underwent frontal and lateral transcranial cerebral oximetry. The lateral probe was only used in 17 patients. METHODS: The percentage decrease of transcranial cerebral oximetry was calculated during cross-clamping. Using the EEG findings as the gold standard in order to detect cerebral ischaemia during carotid cross-clamping, the relationship with transcranial cerebral oximetry was described in terms of sensitivity, specificity and the area under the curve in a receiver operating characteristic curve. RESULTS: The 95% confidence interval of the area under the curve of the receiver operating characteristic of the lateral probe was 0.61-1.00 and that of the frontal probe was 0.65-1.00; therefore there is virtually no difference between the two methods. In 18% of the cases the lateral transcranial cerebral oximetry was hindered by practical failures. CONCLUSION: Considering the lack of additional information and the practical problems experienced with the lateral probe, it was concluded that transcranial cerebral oximetry with a single frontal probe is a practical non-invasive monitoring system and is at least as representative for monitoring cerebral ischaemia during carotid cross-clamping as a lateral probe.

Brain↗
PubMed2002

A kinematic study of lateral unicompartmental arthroplasty.

When the Oxford unicompartmental meniscal bearing arthroplasty (UCA) is used in the lateral compartment 10% of the bearings dislocate. A fluoroscopic study was performed to investigate if abnormal mid-sagittal plane kinematics was related to bearing dislocation. Video fluoroscopy is an accepted means of determining in-vivo knee kinematics in the sagittal plane. Video fluoroscopy was obtained of 5 Oxford lateral UCAs 10 years post-operatively and of five normal knees. Patellar tendon angle (PTA), derived from dynamic fluoroscopic images, was used to describe the joint kinematics. This in-vivo experiment demonstrated that the PTA/knee relationship for the Oxford lateral UCA is similar to the normal knee. Both the normal knee (r(2)=0.99) and the Oxford lateral UCA (r(2)=0.98) demonstrated a linear relationship between flexion angle and PTA. No significant difference in PTA was found between the normal knee and the Oxford lateral UCA. This study demonstrated normal kinematics, as indicated by PTA, ten years after implantation of the Oxford lateral UCA. It is therefore reasonable to suggest that abnormal kinematics is not a significant factor relating to meniscal bearing dislocation in the lateral compartment.

Adult↗