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PubMed1990

The anterior buccal mandibular depression: physical and radiologic features.

The anterior buccal mandibular depression (ABMD), an anatomic variation not previously mentioned in the dental literature, is considered. Its physical and radiologic configuration is evaluated, and its significance in the differential diagnosis of radiolucent lesions in the anterior portion of the mandible is discussed. The general prevalence of ABMD was found to be 19.8%, with a significantly higher prevalence in children (p less than 0.001). In the majority of cases, the depression was radiologically detected. The radiopacity of the area was significantly dependent on depth of the depression (p less than 0.001). The radiographic image of the ABMD resembles, in many cases, the image of the less common anterior lingual salivary gland depression. The relatively high frequency of the ABMD indicates the importance of recognizing its radiologic features.

Adolescent↗

PubMed1994

Human brain responses to different image contrasts.

Human brain activity was evoked by a dynamic random-dot display in which a square-wave grating appeared and disappeared at regular intervals. Grating visibility was determined by one of four different contrasts: texture, stereo disparity, luminance, or color. Scalp fields measured with 31 electrodes were used to estimate epicortical potential fields. The estimation procedure required detailed anatomical data for each subject. These were obtained from magnetic resonance images. A three-dimensional digitizer and a stereotactic headgear were used to accurately merge the frame of reference of the magnetic resonance image with that of the evoked potential. Epicortical potential fields provided a better indicator of where brain activity is evoked than did scalp fields. These procedures also corrected for anatomical variations between scalp and brain from subject to subject. In two right-handed female subjects, evoked activity was observed in the left posterior parietal and the right occipital, parieto-occipital and posterior temporal cortices. Evoked activity was observed in the left parietal cortex for luminance processing, in the right parietal cortex for texture processing and in the right temporal cortex for color processing, which was selective for the particular contrast.

Brain↗

PubMed1989

Focal brain ischemia model in rats. An experimental study.

Using 74 male rats, anatomical variations of branching of the proximal segment of the middle cerebral artery were studied. In 36 rats (28 Sprague-Dawley rats and eight spontaneously hypertensive rats), the middle cerebral artery and/or its branches were occluded at various sites. Occlusion of the middle cerebral artery at the lateral border of the olfactory tract with or without simultaneous ligation of the ipsilateral common carotid artery rarely caused cerebral infarction in Sprague-Dawley rats. Occlusion of the olfactory branch in addition to the trunk of the middle cerebral artery caused large infarction of the pallium in five of eight Sprague-Dawley rats. Occlusion of the middle cerebral artery at the medial border of the olfactory tract caused infarction in the pallium and/or basal ganglia in five of six rats, and neurologic deficits were severe and persistent. Occlusion of the middle cerebral artery at the lateral border of the olfactory tract in spontaneously hypertensive rats caused large infarction with severe neurologic deficits in all eight animals. Possible factors responsible for such diverse differences and the relative value of each group as an experimental model of focal cerebral ischemia in rats were discussed.

Animals↗

PubMed1994

Peripheral anterior inferior cerebellar artery aneurysms.

Two cases of peripheral anterior inferior cerebellar artery (AICA) aneurysms are reported. The first case was a 60-year-old man who showed frequent attacks of subarachnoid hemorrhage (SAH) and hearing disturbance. His aneurysm was obliterated by trapping the AICA and his neurologic status was unchanged compared with preoperatively. The second case had SAH without cranial nerve involvement; this aneurysm was obliterated by neck clipping. He was discharged without neurologic deficit. Peripheral AICA aneurysm has already been reported in 48 cases including arteriovenous malformation-associated cases. This aneurysm may show cranial nerve involvement (seventh and eighth) without SAH as in the case of internal carotid-posterior communicating artery aneurysms. We review the clinical signs of these cases and discuss them from the point of view of anatomic variations of the AICA and internal auditory artery.

Aged↗

PubMed1995

PGP9.5, a ubiquitin C-terminal hydrolase; pattern of mRNA and protein expression during neural development in the mouse.

PGP9.5 is a neurone and neuro-endocrine specific ubiquitin carboxyl terminal hydrolase estimated to form 1-2% of total brain protein. We have examined the temporal and spatial distribution of PGP9.5 mRNA and protein in the developing mouse embryo. These studies show that PGP9.5 is present at high levels in all differentiated neurones throughout the central and peripheral nervous systems at all stages of development. The mRNA is detected in the neural tube 1 day prior to the protein and before neuronal differentiation is underway. Both mRNA and protein are present during the initial appearance of motor and sensory neurones, prior to their peak production. PGP9.5 immunoreactivity was detected using microwave pretreatment of sections in order to unmask epitopes. In general unmasking led to an overall enhancement of immunoreactivity although in some sites, for example the dorsal root and cranial nerve ganglia and the bundle of His, there was evidence for anatomical variation in the distribution of masked versus unmasked protein. The very early expression of PGP9.5 suggests that there is a role for ubiquitin hydrolases in the differentiation of neurone precursors as well as in the differentiated neurone.

Animals↗

PubMed1981

The size of the mastoid air cell system among black and white children with middle ear effusion.

The incidence of middle ear disease among black American children is lower than among white children. Many factors may contribute to this difference. The possibility of an anatomical variation regarding the cellularity of the mastoid process was investigated. The size of the mastoid air cell system was measured in black and white children with and without middle ear effusion. A significantly smaller mastoid air cell system was found in the groups with middle ear disease compared to those without disease. No difference between white and black children in diseased as well as non-diseased ears could be demonstrated.

Black People↗

PubMed1991

Atresia of the left atrioventricular valve with patency of the aorta: anatomico-functional analysis of 23 patients.

We analyzed the findings in 23 patients with atresia of the left atrioventricular valve and a patent aorta seen in the period from January 1980 to July 1989. Having divided the cases according to the anatomical findings, we made a subsequent analysis of the clinical and surgical results with the aim of establishing the management most likely to diminish risks, still high, in treatment of this complex anomaly. From the anatomical viewpoint, three variants were observed. In the first, made up of 15 cases, there was absence of the left atrioventricular connexion. The characteristic finding in the second group, with five cases, was an imperforate left atrioventricular valve in the setting of concordant atrioventricular connexions. The third group, of these cases, was dominated by the presence of isomerism of the atrial appendages, both appendages being of left morphology in one case, and of right morphology in the other two. Further anatomical variation was then found in each group. Nine of the 15 with absence of the left atrioventricular connexion had the right atrium connected to a dominant left ventricle in presence of a rudimentary and incomplete right ventricle associated with discordant ventriculo-arterial connexions, all of them being in usual atrial arrangement and three with pulmonary stenosis. The remaining six in this first variant had the right atrium connected to a dominant right ventricle. In the five patients with imperforate left atrioventricular valves, two had discordant and three had concordant ventriculo-arterial connexions. In the three cases with isomerism, two had absence of the left atrioventricular connexion, with a dominant right ventricle. The last patient had an imperforate left atrioventricular valve and a discordant ventriculo-arterial connexion. From the functional viewpoint, there were 14 patients (10 with absence of an atrioventricular connexion, four with imperforate atrioventricular valve) with congestive heart failure and nine patients (five from the first, one from second, and three from the third variant) with hypoxia. Long-term follow-up (median 16.4 months--varying from 1 to 41 months--in the group with congestion and 27.7 months--varying from 12 to 57 months--in those with hypoxia) showed favorable clinical evolution in 11 (91%). We conclude that an anatomico-functional division can point towards the most appropriate management in this complex anomaly.

Aorta↗

PubMed1992

Dosimetry of intracavitary placements for uterine and cervical carcinoma: results of orthogonal film, TLD, and CT-assisted techniques.

A total of 720 192Ir high-dose-rate (HDR) applications in 331 patients with gynecological tumors were analyzed to evaluate the dose to normal tissues from brachytherapy. Based on the calculations of bladder base, bladder neck, and rectal doses derived from orthogonal films the planned tumor dose or fractionation was altered in 20.4% of intracavitary placements (ICP) for cervix carcinoma and 9.2% of ICP for treatment of the vaginal vault. In 13.8% of intracervical and 8.1% of intravaginal treatments calculated doses to both the bladder and rectum were greater than or equal to 140% of the initially planned dose fraction. Doses at the bladder base were significantly higher than at the bladder neck (p less than 0.001). In 17.5% of ICP the dose to the bladder base was at least twice as high as to the bladder neck. The ratio of bladder base dose to the bladder neck was 1.5 (+/- 1.19 SD) for intracervical and 1.46 (+/- 1.14 SD) for intravaginal applications. The comparison of calculated doses from orthogonal films with in-vivo readings showed a good correlation of rectal doses with a correlation coefficient factor of 0.9556. CT-assisted dosimetry, however, revealed that the maximum doses to bladder and rectum were generally higher than those obtained from films with ratios of 1-1.7 (average: 1.44) for the bladder neck, 1-5.4 (average: 2.42) for the bladder base, and 1.1-2.7 (average: 1.37) for the rectum. When doses to the specified reference points of bladder neck and rectum from orthogonal film dosimetry were compared with the corresponding points on CT scans, similar values were obtained for both methods with a maximum deviation of +/- 10%. Despite the determination of multiple reference points our study revealed that this information was inadequate to predict doses to the entire rectum and bladder. If conventional methods are used for dosimetry it is recommended that doses to the bladder base should be routinely calculated, since single point measurements at the bladder neck seriously underestimate the dose to the bladder. Also the rectal dose should be determined at several points over the length of the implant due to the wide range of anatomic variations possible.

Brachytherapy↗

PubMed1992

Developmental toxicity of boric acid in mice and rats.

Boric acid (BORA), an ingredient of many cosmetics, pharmaceuticals, and pesticides, was tested for developmental toxicity in timed-pregnant Swiss mice and Sprague-Dawley rats (n = 26-28/group). BORA (0, 0.1, 0.2, or 0.4% in feed) was provided throughout gestation to attain steady-state exposure as early as possible during prenatal development. Average doses (mg/kg/day) were 248, 452, or 1003 in mice, and 78, 163, or 330 in rats. To limit prenatal mortality, BORA (0.8% or 539 mg/kg/day) was provided to an additional group of rats on Gestational Days (GD) 6 to 15 only. On GD 17 (mice) or 20 (rats), fetuses were weighed and examined for malformations (external, visceral, skeletal). Mouse dams exhibited mild renal lesions (greater than or equal to 0.1%), increased water intake and relative kidney weight (0.4%), and decreased weight gain (0.4%) during treatment. There was a reduction of fetal body weight (greater than or equal to 0.2%) and an increased incidence of resorptions and malformed fetuses per litter (0.4%). Morphological changes included an increased incidence of short rib XIII (a malformation) and a decreased incidence of rudimentary or full rib(s) at lumbar I (an anatomical variation). Maternal rats exhibited increased liver and kidney weights at greater than or equal to 0.2%, altered water and/or food intake at greater than 0.2%, and decreased weight gain at greater than 0.4%. Average fetal body weight/litter was reduced at all doses. Prenatal mortality was increased only at 0.8%. The incidence of fetal malformations was significantly increased at greater than or equal to 0.2%. The most frequently observed malformations were enlarged lateral ventricles of the brain and agenesis or shortening of rib XIII. In rats, the no-observable-adverse-effect level (NOAEL) for maternal toxicity was 78 mg/kg (0.1%), while in mice the low dose of 248 mg/kg (0.1%) approached the maternal NOAEL with mild renal lesions in only 2 of 10 females. Embryo/fetal toxicity occurred in all groups of rats at greater than or equal to 78 mg/kg (greater than or equal to 0.1%) while the NOAEL for developmental toxicity in mice was 248 mg/kg (0.1%). Thus developmental toxicity occurred below maternally toxic levels in rats as well as in the presence of maternal toxicity in mice and rats.

Abnormalities, Drug-Induced↗

PubMed1987

Noninvasive assessment of normal carotid bifurcation hemodynamics with color-flow ultrasound imaging.

The combination of a B-mode imaging system and a single range-gate pulsed Doppler flow velocity detector (duplex scanner) has become the standard noninvasive method for assessing the extracranial carotid artery. However, a significant limitation of this approach is the small area of vessel lumen that can be evaluated at any one time. This report describes a new duplex instrument that displays blood flow as colors superimposed on a real-time B-mode image. Returning echoes from a linear array of transducers are continuously processed for amplitude and phase. Changes in phase are produced by tissue motion and are used to calculate Doppler shift frequency. This results in a color assignment: red and blue indicate direction of flow with respect to the ultrasound beam, and lighter shades represent higher velocities. The carotid bifurcations of 10 normal subjects were studied. Changes in flow velocities across the arterial lumen were clearly visualized as varying shades of red or blue during the cardiac cycle. A region of flow separation was observed in all proximal internal carotids as a blue area located along the outer wall of the bulb. Thus, it is possible to detect the localized flow patterns that characterize normal carotid arteries. Other advantages of color-flow imaging include the ability to rapidly identify the carotid bifurcation branches and any associated anatomic variations.

Adult↗

PubMed1982

Trigeminal neuralgia as a consequence of circulatory disorders in the infratemporal and pterygopalatine fossae.

An extensive review of the well documented experimental and clinical findings related to trigeminal neuralgia shows, that it is possible to set up an unifying theory for trigeminal neuralgia, which would explain most clinical features of the disease and also would be congruent with several other theories that have previously been presented. Thus, trigeminal neuralgia is proposed to be the result of a combination of predisposing anatomical variations, impaired arterial and venous circulation, and morphological changes in the infratemporal fossa and cavum Meckeli. The process is initiated by disturbances of dental occlusion and mandibular function, resulting in muscular hypertrophy, which finally leads to increased perineural pressure and hypoxia in the nervous tissue. Through a series of related events this results in massive afferent discharges in the trigeminal nerve, which are strong enough to break through an inhibitory gating mechanism in the nucleus caudalis, and which are experienced by the patient as a pain attack. But the tissue hypoxia, which partly has elicited the pain, will finally also be the critically delimiting factor for further signal transmission, thereby stopping the pain attack.

Humans↗

PubMed1991

Avascular necrosis and vascular anatomy of the metacarpals.

Aseptic necrosis of the metacarpal head is extremely rare and has been described in association with systemic lupus erythematosus, steroid use, trauma, and other sites of bone infarction. The long metacarpal is the most commonly involved. The extrinsic and intrinsic vascular anatomy of the metacarpal is described in fifty metacarpal specimens. No definite conclusions can be drawn about anatomic variations in blood supply between the different metacarpals. However, in 35% of the specimens, a main arteriole in the distal epiphysis was absent, making these metacarpal heads solely dependent on small circumferential pericapsular arterioles. This group of metacarpals, when associated with other risk factors, such as trauma, systemic lupus erythematosus, or steroid use, may be at increased risk for the development of aseptic necrosis.

Adolescent↗

PubMed1979

Imaging of the pancreas with computed tomography.

In this paper we present our experience with computerized tomographic imaging of the pancreas, both in normal and abnormal conditions. Eighty patients were studied for evaluation of pancreatic disease. A further 50 patients, all with a normal pancreas, were studied for abnormalities of other abdominal organs and served as the control group. Helpful signs in establishing the diagnosis of carcinoma of the pancreas were mass effect within the pancreas, alteration of organ contour and obliteration of retroperitoneal fat planes. We found that differentiation from pancreatitis or retroperitoneal lymphadenopathy may at times be difficult. Our results showed that in 22 out of 23 patients with proven normal pancreas, the pancreas size on the CT display was within the adopted normal range. In 30 patients with proven carcinoma of the pancreas, a pancreatic mass was seen in 24 (83%). Computerized tomography is clearly a valuable method for viewing both normal pancreatic anatomy and anatomical variations and pathologies.

Adipose Tissue↗

PubMed1995

Magnetic resonance venography in liver bipartition procedures using preservation solution as contrast agent.

To evaluate whether the hepatic veins can be visualized with a rapid noninvasive technique, and if so, whether the obtained images could be helpful in the preparation of split liver grafts for transplantation, six cold stored human donor livers were investigated with magnetic resonance imaging (MRI). The hepatic vein branches and their confluence were clearly visualized. Anatomic variations of the middle hepatic vein with consequences for the choice of the transection plane could be demonstrated. Furthermore, unexpected vascular abnormalities were detected. From these preliminary results it is concluded that visualization of the hepatic veins can be helpful in determining the feasibility of the bipartition procedure and the choice of the transection plane. A potential wide application of this fast and noninvasive technique is possible.

Adenosine↗

PubMed1995

Magnetic resonance angiography in 140 neuropediatric patients.

Three-dimensional magnetic resonance angiography (MRA) is a noninvasive technique that images the intracranial arterial vasculature without contrast agents. The suitability of MRA was evaluated for routine use and all children were prospectively studied with conventional MR imaging and time off flight MRA (FISP3D). All MR studies were performed on a 1.5 T-MRA system using a circularly polarized head coil. The study comprised 140 children, ages 3 weeks to 18 years, with different neuropediatric diseases. Major cervical and intracranial arteries were visualized in all age groups. Smaller branches of the supratentorial arteries were identified inconstantly and the number of arteries visualized increased up to the age of 6 years. Sixty-seven children (47%) had normal intracranial vasculature. MRA demonstrated anatomic variations in 21 patients (15%). Twenty-two of 32 children with congenital malformations demonstrated abnormalities of the intracranial vasculature. The diagnostic value of MRA was confirmed in 11 of 12 patients after neonatal stroke and in 3 of 10 children after stroke at older ages. Seven of 18 children with acute hemorrhage demonstrated arteriovenous malformations or an aneurysm on MRA. The correlation with digital subtraction angiographic findings was established in 13 patients. In 9 of 13 children with brain tumor, MRA proved to be diagnostically valuable. MRA proved to be of particular value in the evaluation of the carotid artery following extracorporeal membrane oxygenation therapy. MRA can be used in children of all age groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed2005

Insertional pattern of the inferior oblique muscle.

PURPOSE: We aimed to define the anatomy and anatomic variations of the inferior oblique muscle (IO) and classify its insertional pattern with photographs and drawings. DESIGN: Cohort study. METHODS: This study included 60 intact orbits of 30 (17 male and 13 female) embalmed adult cadavers. The inferior oblique muscle was dissected microanatomically from the origin to the insertion by using a dissection microscope. For each specimen, we photographed the insertional pattern of the muscle. A Vernier caliper was used to measure the width and length of the muscle at the insertion and from the division to the insertion, respectively. RESULTS: We classified the inferior oblique muscle into four groups according to the insertional pattern. In the first group, the muscle was formed of only one belly ("single," five eyes, 8.3%). In the second group, the muscle had a main and a secondary belly ("double," 30 eyes, 50%). In the third group, the muscle had three bellies ("triple," 16 eyes, 26.6%). In the fourth group, the muscle had more than three bellies ("multiple," 9 eyes, 15%). CONCLUSIONS: We found double, triple, and multiple muscle bellies in 91.7% of 60 cadaveric eyes. Ocular surgeons who do not frequently perform inferior oblique surgery should carefully examine the inferior temporal quadrant of the sclera to avoid missing portions of the inferior oblique muscle at the time of surgery.

Adult↗

PubMed2005

Pelvic organ descent and symptoms of pelvic floor disorders.

OBJECTIVE: This study evaluates the relationship between symptoms of pelvic floor disorders, and measurement of pelvic organ prolapse. STUDY DESIGN: This retrospective cross-sectional study assessed prolapse in 905 women in an academic urogynecologic practice using the Pelvic Organ Prolapse Quantification exam. Symptoms were assessed with a Likert symptom questionnaire and the Urogenital Distress Inventory. Relationships between symptoms and prolapse were analyzed using Spearman's correlation. RESULTS: Symptoms of "bulging" correlated moderately to the greatest extent of prolapse (r=0.4, P<.001). Frequency of bother progressively increases when the leading edge descends from -3 and 0. Between +1 and +5, 90% of women report bother. Symptoms typically attributed to anterior or posterior wall prolapse did not correlate with descent of the respective compartment. CONCLUSION: "Bulging" is the principle symptom that correlates with prolapse severity. We found no discrete anatomic position that discriminates between prolapse as a disease state and normal anatomic variation.

Cross-Sectional Studies↗

PubMedDate not supplied

Two consecutive cases of cerebrospinal fluid rhinorrhea after septoplasty operation.

Our aim in this work is to define the importance of anatomical knowledge in septoplasty operation and to prevent complications. Septoplasty is one of the most common operations in otorhinolaryngology to treat the nasal obstruction caused by septal deviation. During and after septoplasty, there are some recorded complications, such as hemorrhage, hematoma, septal abscess, septal perforation, saddle nose, infection, anosmia, visual disturbances, cavernous sinus thrombosis, meningitis, pneumoencephalos, subarachnoid hemorrhage, subdural empyma, brain abscess, periorbital emphysema, toxic shock syndrome, and cerebrospinal fluid (CSF) rhinorrhea. Some of the complications are rare, but their results are life threatening. We report a rare complication of septoplasty CSF rhinorrhea. Two consecutive cases of CSF fistulas after septoplasty operation are presented. Both of the cases were treated endoscopically. The possible mechanisms and different treatment options are discussed. Prevention of the CSF fistula in septoplasty is more important than its treatment. Realizing the anatomic variations and gentle manipulation at the ethmoid roof is essential.

Adult↗