Paramedian Area Research Articles

Atypical Course of the Habenulo-Interpeduncular Tract in Chick Embryos.

Classical studies of the avian diencephalon hardly mention the habenulo-interpeduncular tract (a.k.a. retroflex tract), although both the habenula (HB) (its origin) and the interpeduncular nuclear complex (its target) are present. Retroflex tract fibers were described at early embryonic stages but seem absent in the adult in routine stains. However, this tract is a salient diencephalic landmark in all other vertebrate lineages. It typically emerges out of the caudal HB, courses dorsoventrally across thalamic alar and basal plates just in front of the thalamo-pretectal boundary, and then sharply bends 90° caudalwards at paramedian basal plate levels (this is the "retroflexion"), to approach longitudinally via paramedian pretectum and midbrain the rostralmost hindbrain, specifically the prepontine median interpeduncular complex across isthmus and rhombomere 1. We systematize this habenulo-interpeduncular course into four parts named subhabenular, retrothalamic, tegmental, and interpeduncular. We reexamined the chicken habenulo-interpeduncular fibers at stages HH30 and HH35 (6.5- and 9-day incubation) by mapping them specifically with immunoreaction for BEN protein, a well-known marker. We found that only a small fraction of the stained retroflex tract fibers approaches the basal plate by coursing along the standard dorsoventral pathway in front of the thalamo-pretectal boundary. Many other habenular fibers instead diverge into atypical dispersed courses across the thalamic cell mass (implying alteration of the first subhabenular part of the standard course) before reaching the basal plate; this dispersion explains their invisibility. A significant number of such transthalamic habenular fibers cross orthogonally the zona limitans (ZLI) (the rostral thalamic boundary) and invade the caudal alar prethalamus. Here, they immediately descend dorsoventrally, just rostrally to the ZLI, until reaching the prethalamic basal plate, where they bend (retroflex) caudalwards, entering the thalamic basal paramedian area. These atypical fibers gradually fasciculate with the other groups of habenular efferent fibers in their final longitudinal approach to the hindbrain interpeduncular complex. We conclude that the poor visibility of this tract in birds is due to its dispersion into a diversity of atypical alternative routes, though all components eventually reach the interpeduncular complex. This case merits further analysis of the diverse permissive versus nonpermissive guidance mechanisms called into action, which partially correlate distinctly with successive diencephalic, mesencephalic, and hindbrain neuromeric fields and their boundaries.

Clinical characteristics in patients with oculomotor paralysis caused by isolated midbrain infarction.

The aim of the study was to investigate the clinical characteristics of isolated oculomotor paralysis (OP) cases caused by pure midbrain infarction (MI) with pupil sparing. Patients with pure MI and pontine infarction (PI) at our hospital were included in this study. We compared the blood pressure and lipid levels between the two groups. And the clinical data and imaging features were summarized. In total, 33 and 35 patients were included in the MI and PI groups, respectively. There was no significant difference in the distribution of age (64.9 ±10.0 vs. 65.1 ±10.8 years, p = 0.927) and males (84.8% vs. 74.3%, p = 0.282) between the MI and PI groups, respectively. The pure MI group had a comparable level of serum lipoprotein and cardiovascular risk factors compared with the PI group except for a lower proportion of hypertension (57.6% vs. 85.7%, p = 0.010). The majority (72.7%) of culprit lesions in the pure MI group was located in the paramedian area of the midbrain, and the ocular muscle palsies mostly involved the medial rectus (75.8%). The Chinese patients with OP caused by pure MI were mainly characterized with rapidly progressive symptoms, multiple cerebrovascular risk factors, and typical MRI signs. Further efforts should be made in the differential diagnosis of this atypical midbrain syndrome.

Risk of root damage after using lateral cephalogram and intraoral scan for guided insertion of palatal miniscrews

BackgroundGuided insertion of palatal miniscrews using a lateral cephalogram instead of cone beam computed tomography (CBCT) significantly reduces the radiation level for the patient. Till now no data are available on the risk of hitting the incisors in this regard, which is one of the worst clinical complications when inserting a paramedian miniscrew. Hence, this study aims to investigate the distance between the mini-implant and the roots of the central and lateral incisors.MethodsLateral cephalogram, an intraoral scan, and CBCT of 20 patients were superimposed. After a miniscrew (1.7 × 8 mm) placement based on intraoral scan and lateral cephalogram, the CBCT was used as control for the distance between the miniscrews and the roots of the incisors.ResultsThe mean value of the shortest distance between the miniscrew and roots of the incisors in the lateral cephalogram was 4.74 ± 1.67 mm. The distance between both miniscrews and the central incisors measured in the CBCT was 5.03 ± 2.22 mm and 5.26 ± 2.21 mm and between the two miniscrews and the lateral incisors was 4.93 ± 1.91 mm and 5.21 ± 2.64 mm. No significant differences between the distances in the CBCT and the lateral cephalogram could be observed. In one case, the CBCT control revealed the penetration of two palatally displaced canines after insertion based on intraoral scan and lateral cephalogram.ConclusionsThe use of an intraoral scan and a lateral cephalogram for guided paramedian insertion of palatal miniscrews can prevent incisor root damage. This may reduce the radiation since no CBCT seems necessary. The current investigation focuses on the anterior paramedian area of the palate. Outside that region and in complex cases with displaced teeth in the palatal area, a CBCT might be indicated.

MARPE

Contracted maxillary arch has always been a major concern to those who have interested themselves in regulation of teeth. Rapid expansion of maxilla by forceful separation has been discussed in orthodontic literature revealing considerable controversy over the desire and possibility of splitting the hard palate at the midsagittal suture as a mean of widening the dental arch and nasal cavity. Incorporation of mini screws in a conventional RPE appliance transforms it into a MARPE appliance. Mini screws ensure maximum skeletal expansion, keeping the dental expansion and resultant side effects to a minimum. Various designs have been recommended by authors around the globe; exclusively bone borne, teeth-bone borne and tissue-bone borne with two/ four mini screws in the assembly. Paramedian area 3 mm lateral to the suture in 1st premolar region is considered the most appropriate site for placement of mini screws. Anterior screws are placed in the rugae area while posterior screws in the para-midsagittal area.

Novel localizations of TRPC5 channels suggest novel and unexplored roles: A study in the chick embryo brain.

Mammalian TRPC5 channels are predominantly expressed in the brain, where they increase intracellular Ca2+ and induce depolarization. Because they augment presynaptic vesicle release, cause persistent neural activity, and show constitutive activity, TRPC5s could play a functional role in late developmental brain events. We used immunohistochemistry to examine TRPC5 in the chick embryo brain between 8 and 20 days of incubation, and provide the first detailed description of their distribution in birds and in the whole brain of any animal species. Stained areas substantially increased between E8 and E16, and staining intensity in many areas peaked at E16, a time when chick brains first show organized patterns of whole-brain metabolic activation like what is seen consistently after hatching. Areas showing cell soma staining match areas showing Trpc5 mRNA or protein in adult rodents (cerebral cortex, hippocampus, amygdala, cerebellar Purkinje cells). Chick embryos show protein staining in the optic tectum, cerebellar nuclei, and several brainstem nuclei; equivalent areas in the Allen Institute mouse maps express Trpc5 mRNA. The strongest cell soma staining was found in a dorsal hypothalamic area (matching a group of parvicellular arginine vasotocin neurons and a pallial amygdalohypothalamic cell corridor) and the vagal motor complex. Purkinje cells showed strong dendritic staining at E20. Unexpectedly, we also describe neurite staining in the septum, several hypothalamic nuclei, and a paramedian raphe area; the strongest neurite staining was in the median eminence. These novel localizations suggest new unexplored TRPC5 functions, and possible roles in late embryonic brain development.

Quantitative evaluation of palatal bone thickness to guide miniscrews insertion: a CBCT assessment

Introduction: The use of mini-implants has become common in orthodontic practice as it has increased the possibility of skeletal anchorage. The palate constitutes a site of choice for the insertion of miniscrews purposes because it is a site with relatively safety with appropriate bone thickness and less suitability for inflammation. Aim: To quantitatively evaluate the thickness of the palatal bone for miniscrews insertion. Material and Methods: Forty-seven sets of cone beam computed tomographic (CBCT) images were selected. The sample consisted of cone beam computed tomography from 47 patients (20 male, 27 female; mean age 22.4 years old/± 3.01 years). Palatal bone thickness (PBT) was measured in millimeters (mm) with 5 regions of interest (ROIs) which were determined used the coronal reconstructions of the patatal area: 4, 6, 8 and 10 mm posterior to the incisive foramen were evaluated. A total of 940 ROIs were evaluated. RESULTS: Significant differences were observed for PBT between various palatal sections (p<.01). The thickest area (6.31-7.03 mm) was found in the anterior part of the palate. The mean bone thicknesses in the 6, 8 and 10 mm sections were significantly less than those observed at 4 mm from the incisive foramen. Conclusions: The thickness of the palatal bone is progressively thinner from the palatine foramen to the posterior region. Transversally, the bone was thicker in the palatine suture than in paramedian areas, mainly in the coronal reconstructions located more laterally.

Histomorphological investigations on the lips of Rahmani sheep (Ovis aries): A scanning electron and light microscopic study.

This study was conducted to provide comprehensive information on the anatomical and histological features of the upper (UL) and lower (LL) lips of Rahmani sheep by gross examination, morphometric analysis in addition to Light and scanning electron microscope (SEM). Samples from normal healthy adult male sheep heads were collected directly after slaughtering. UL and LL were dissected, and specimens were collected for both light and SEM. The UL was longer approximately by one-fold and thicker by one-fold at the median and the oral angle areas, and by one- and half-folds at the paramedian area than the LL. The free border of both lips was characterized rostrally by the presence of labial projections. By SEM the edges of the inner aspect of the lips and of the philtrum were distinguished by labial projections. These projections which surrounding the philtrum subdivided into polygonal areas with numerous keratinized scales especially at the apical parts which increased dorsally toward the nostril. Most of the openings of the upper labial salivary glands were volcanic crater-shaped while that of the lower labial salivary glands were various shapes; round folded margin, rosette and whirlpool shaped. Histologically, the shape of the projection or papillae differs at the median and paramedian areas of the UL than the LL. However, there was no differences near the oral angle area. In conclusion, the shape, size and amount of keratinization of the papillae may offer efficiency to the lips during feeding process.

Evaluation of total bone and cortical bone thickness of the palate for temporary anchorage device insertion

Background/purposeThe palate has become a popular site for the placement of temporary anchorage devices (TADs) owing to its bone quantity and quality. This study aimed to investigate total and cortical bone thicknesses in the whole palate as well as palatal width using a standard grid system and cone-bean computed tomography (CBCT) images. Materials and methodsThe CBCT images of 43 samples were selected. The total bone and cortical bone thicknesses of the palate were surveyed on 64 points per patient. The palatal width was measured. The difference between the age and sex groups was analyzed. ResultsThe total palatal bone thickness in the adult group ranged from 9.85 ± 2.04 to 1.87 ± 0.79 mm. In the adolescent group, we found one-third of the incisor roots in the area 3 mm distal to the incisive foramen and 8 mm lateral to the mid-palatal suture. The cortical bone thickness in adults was significantly thicker in the posterior paramedian area than that in adolescents. ConclusionThe thickest vertical bone is located in the zone 3 mm distal to the incisive foramen and 4–8 mm lateral to the midpalate. The zone 6 mm posterior to the incisive foramen and 2–8 mm lateral to the midpalate exhibited optimal thickness and was away from the incisor roots. This region could be a safe zone for adolescent patients to place TADs. When TADs are to be inserted at the posterior palate, the 2-mm paramedian area should be the first region of choice.

Suitability of virtual plaster models superimposed with the lateral cephalogram for guided paramedian orthodontic mini-implant placement with regard to the bone support.

PurposeThe purpose of this study was twofold: first, to evaluate the precision of guided orthodontic mini-implant (OMI) placement planned on virtual superimposition of plaster models and lateral cephalograms with regard to the bone support and, second, to investigate the effects of silicone guide extension.MethodsA total of 40 OMIs were placed in the paramedian area of the anterior palates of 20 cadaver heads. Digitalized models and the corresponding lateral cephalograms were superimposed for planning the OMI positions, and tooth-supported (TS) and soft-tissue-supported (STS) templates were manufactured. Thereafter, postoperative cone beam computed tomography (CBCT) was performed, and the straight (A) and right-angle distance (B) from the implant tip to the nasal floor, the distance from the implant shoulder to the hard palate (C) and the angle (α) between the implant and palate plane with the preoperative (T0) and postoperative (T1) positions were measured.ResultsThe postoperative distances A, B, and C were less than the planned implant positions. However, significant difference between T0 and T1 was only noted in terms of distance A using the TS templates (T0: 4.7 ± 2.3 mm, T1: 3.0 ± 2.3 mm; p = 0.008) and distance B using the STS template (T0: 3.1 ± 3.5 mm, T1: 2.3 ± 3.2 mm; p = 0.041). There were no significant differences in all average deviations (∆ Ceph/CBCT) between the two templates.ConclusionsGuided OMI placement planned by virtual superimposition of digitized models and the corresponding lateral cephalogram is fundamentally feasible. However, the position closer to the nasal floor needs critical assessment for correct implantation. The silicone template expansion seems to have only a minor effect on transfer accuracy.

Supracerebellar Infratentorial Endoscopy for Quadrigeminal Cistern Epidermoid

The standard microscopic supracerebellar infratentorial approach for the pineal region is limited by tunnel vision. Herein, we describe endoscopic supracerebellar infratentorial surgery in a patient with quadrigeminal cistern epidermoid presenting with hydrocephalus. In the sitting position, following a 6 cm longitudinal incision and small suboccipital craniotomy, the dura was cut in V shape and kept reflected. The bridging veins were coagulated and cut, taking the 0° endoscope inside. A sharp incision is given over the thickened arachnoid over the inferior paramedian area. The precentral cerebellar vein is exposed at the lower part, coagulated and divided. Gentle bimanual intracapsular removal of the epidermoid flakes is performed with intermittent saline irrigation and suction. Assisted by rotating the angled endoscope, curved coaxial instruments help remove the cerebello-mesencephalic and lateral extensions of the epidermoid. Endoscopic supracerebellar infratentorial approach provides a panoramic and angled view of the pineal region, through a narrow corridor, avoiding cerebellar retraction.

Pursuit for Optimum Skeletal Expansion: Case Reports on Miniscrew Assisted Rapid Palatal Expansion (MARPE)

Incorporation of mini screws in a conventional RPE appliance transforms it into a MARPE appliance. Mini screws ensure maximum skeletal expansion, keeping the dental expansion and resultant side effects to a minimum. Various designs have been recommended by authors around the globe; exclusively bone borne, teeth-bone borne and tissue-bone borne with two/ four mini screws in the assembly. Paramedian area 3 mm lateral to the suture in 1st premolar region is considered the most appropriate site for placement of mini screws. Anterior screws are placed in the rugae area while posterior screws in the para-midsagittal area. This article (case series) describes three cases treated with MARPE appliance designs and protocols.

Isolated INO as a presentation of midbrain paramedian area lacunar infarction in patients with diabetes

The clinical features and pathogenesis of the pure midbrain infarction need to be described. Of 4257 stroke patients who were on the stroke registry between January 2000 and December 2015, 25 patients with pure midbrain infarctions, as demonstrated on diffusion-weighted magnetic resonance imaging, were enrolled. We analyzed the clinical features, MRI findings, and etiologic mechanisms of the infarctions. According to the distribution of each penetrating artery of the midbrain, we classified all the infarctions into paramedian (PM) area (13 patients), lateral area (10 patients), and PM and lateral areas (2 patients). In the lacunar infarction of the PM area group (8 patients), 6 patients had diabetes mellitus (DM), and 5 patients showed isolated anterior internuclear ophthalmoplegia (INO)—the ratio was much higher than that of the non-PM-lacunar infarction group. Patients with DM were more likely to develop lacunar infarction of the midbrain PM area than that of non-diabetics. Data suggest that isolated INO is a presentation of midbrain PM area lacunar infarction in patients with DM.

Bertolotti Syndrome

Bertolotti syndrome is caused by a lumbosacral transitional vertebra, a congenital variation of the most caudal lumbar vertebra, characterized by an enlarged transverse process that articulates or fuses with the sacrum, ilium, or both. This syndrome accounts for 4.6 to 7% of cases of low back pain in adults and for more than 11% of patients with low back pain who are under 30 years old. The primary effect of lumbosacral transitional vertebra is reduced and asymmetrical motion between the transitional vertebra and the sacrum, resulting in early arthritic changes at pseudoarticulation; the secondary effect is the progressively compensatory modifications in the biomechanics of the mobile vertebral segments superior to the transitional vertebra related to restriction in rotation and bending motion at the lumbosacral articulation. Bertolotti syndrome should be considered in the differential diagnosis of low back pain. Clinical findings include low back pain in the midline or paramedian area that is reproduced with palpation along the base of the lumbosacral spine and near the posterosuperior iliac spine and aggravated by forward flexion, excessive extension, or lateralization of the back to the same side of the mega-apophysis. A plain x-ray is diagnostic; the extension-flexion lumbosacral radiographs in anteroposterior, lateral, and oblique views demonstrate lumbosacral transitional vertebra, with an enlarged unilateral or bilateral transverse process of the most distal lumbar vertebra, abnormally articulating with the ala of the sacrum and degenerative changes of the pseudarthrosis. Other imaging studies, such as computed tomography and magnetic resonance imaging of the lumbosacral spine and selective radiculography of the spinal nerve, could provide additional detailed anatomic information. Major differential diagnoses of Bertolotti syndrome include sacroiliac joint pain, myofascial pain, lumbar facet pain, lumbar disk herniation, compression fracture, and Baastrup disease/interspinous bursitis. These conditions are not mutually exclusive and, in fact, often coexist. A course of conservative management, including activity modification, medication management with nonsteroidal antiinflammatory drugs, muscle relaxants, and rehabilitative physical therapy, should be offered initially. Due to the multifactorial etiology of low back pain in patients with Bertolotti syndrome, procedures such as diagnostic intrapseudoarticular block for arthritis, medial branch block for facet arthropathy, diskography for diskogenic pain, and selective nerve roots block for radiculopathy can potentially help identify the primary and secondary origins of the pain. Surgical treatment of Bertolotti syndrome was only slightly better than conservative treatment and should only be used in very selective patients with disk pathology. To achieve long-term improvement by any of these therapeutic options, a continuing physical rehabilitation program is often needed. Key words: Bertolotti syndrome, intrapseudoarticular block, transitional lumbosacral vertebra, transverse process

Surgical Technique for Cervical Pedicle Screw Insertion using O-Arm

Introduction Posterior cervical fixation using lateral mass screw and cervical pedicle screw (CPS) is getting available for various disorders such as trauma and degenerative disease and so on. The purpose is to report our detail surgical technique for CPS insertion using O-Arm, about cannulated CPS particularly. Material and Methods Consecutive one hundred twenty patients underwent posterior cervical fixation using CPSs since January 2007. Preoperatively we made further evaluation of the each patient's radiological condition including collateral circulation using MRI and MR angiography and CT angiography. We evaluated local instability with dynamic cervical radiography at each. During making pilot hole of CPS, usually we have felt resistant strong force which cervical back muscles and subcutaneous tissues have produced. So if we made short midline skin incision in particular, CPS underwent through the bilateral another skin incision which we made at the paramedian area. Using O-arm, CPSs were inserted slowly and intermittently taking care not to produce axial rotation or sagittal bending of the cervical spine, which related to the screw malposition including VA injury. And recently we used to use the cannulated screw. Results We inserted 668 CPS and classified their position with Neo's classification using postoperative CT scan, grade 0 (635 screws, 95.0%), grade 1 (27 screws, 4.0%), grade 2 (6 screws, 0.9%), grade 3 (0 screws). No neurovascular complications associated with surgery were encountered. Conclusion We believe what is the most important for safe CPS insertion is preoperative detail further evaluation including the indication of CPS. We think our procedure and techniques for CPS insertion are useful and safe.

Dural arteriovenous malformation at the right paramedian area of skull base in a 52 year old male: a case report

Dural arteriovenous malformation at the right paramedian area of skull base in a 52 year old male: a case report

Isolated unilateral oculomotor paresis in pure midbrain stroke

Background and purposePure midbrain stroke can cause isolated unilateral oculomotor paresis. We attempted to determine whether there is a difference in the oculomotor paresis pattern between pure midbrain infarction and midbrain hemorrhage. MethodsPure midbrain stroke patients who presented with isolated unilateral oculomotor paresis were identified from a group of 2447 consecutive patients hospitalized for acute cerebral infarction or hemorrhage during the period May 2008 through April 2014. Detailed oculomotor findings were evaluated in the identified patients per the cause of the stroke. ResultsFive patients with infarct and 1 with hemorrhage became our study subjects. Lesions were located in the paramedian area of the midbrain involving the oculomotor fascicles. The pupillary sphincter and inferior rectus muscles were selectively spared in the infarct patients, whereas these muscles were selectively affected in the hemorrhage patient. ConclusionFibers in the oculomotor fascicle that innervate the levator palpebrae, superior rectus, and inferior oblique muscles appear to be more susceptible to ischemic damage than those that innervate the pupillary sphincter and inferior rectus muscles. Isolated impairment of the pupillary sphincter and inferior rectus muscles may be suggestive of a non-ischemic process.

A Case of Midbrain and Thalamic Infarction Involving Artery of Percheron.

Blood supply to the thalamus and brainstem have frequent anatomic variations. One of these is where all the perforators to the above areas arise from a single branch of the posterior cerebral artery commonly known as the artery of Percheron. Infarction involving this artery leading to bilateral thalamic and midbrain lesions is not uncommon, but can cause diagnostic difficulties due to the varying clinical presentations possible and the wide differentials. Early brain imaging and diagnosis is important for initiating appropriate treatment. In this case report, we discuss a patient who presented with an artery of Percheron related stroke affecting the mid brain and paramedian thalamic areas. We also discuss the differentials of presentations with similar symptoms.

Hard palate thickness for temporary anchorage devices placement: Differences in sex and ethnicity

PurposeThe purpose of this study is to determine variations in hard palate thickness among sexes and four ethnic groups to identify optimum area for temporary anchorage devices (TADs) placement. Materials and methodsCone-beam computed tomography (CBCT) volume data on 160 patients were selected. Patients belonged to one of four ethnic groups (Asian, African-American, Caucasian or Hispanic; 20 men and 20 women in each group, 16–45 years old). Hard palate thickness from the incisor fossa to the palatal root of the maxillary first molar was determined on each image and compared between sexes and ethnic groups. ResultsThe data revealed that thickness was greatest at the paramedian area in the incisive canal zone (C-zone) and the median area posterior to the incisive foramen. A significant difference in thickness of palate was confirmed between sexes, and was approximately 0.5mm and 1mm greater in men at the median and paramedian, respectively. Among ethnic groups, a trend of decreasing thickness was as follows: Caucasian>Hispanic>African-American>Asian. ConclusionThe anterior (incisive canal zone) paramedian and posterior median areas of the hard palate were thicker and suggest that these areas are appropriate for TADs placement. Some differences were also observed local to the paramedian in the C-zone among ethnicities. This indicates that sex and ethnicity should be taken into consideration in selecting sites for placement of TADs.

Ultrasonographic examination of the abdomen of the goat. I. Reticulum, rumen, omasum, abomasum and intestines

This review article summarizes the ultrasonographic findings of the reticulum, rumen, omasum, abomasum and intestines of goats. Ultrasonographic examination is done on both sides with the goat in a standing position using a linear array or convex transducer with a frequency of 5.0 to 7.5 MHz. The shape, contour and motility of the reticulum are assessed; this organ appears as a crescent-shaped structure with a smooth contour immediately adjacent to the diaphragm. There are 0.8 to 2.1 reticular contractions per minute, which may be mono-, bi- and triphasic. The rumen is examined from the 8th to 12th intercostal spaces (ICSs) and flank on the left, and from the 12th ICS and flank on the right. The ruminal wall appears as a thick echoic line. The dorsal and ventral sacs of the rumen are differentiated based on the longitudinal groove, which forms an echoic notch. Differentiation of the dorsal gas cap, fibre mat and fluid layer is not always straightforward and varies among goats. The omasum is examined from the 6th to 11th ICSs on the right. Only the wall closest to the transducer can be imaged and it appears as a crescent-shaped echoic line medial to the liver. The omasal folds and the wall furthest from the transducer cannot be seen. In about two thirds of goats, active omasal motility is apparent as a transient reduction in size of several centimetres, followed by relaxation and return to its original size. There is an average of 1.1 contractions per minute. The abomasum is examined from the ventral midline and the left and right paramedian regions and can always be seen from the ventral midline. In all but a few goats the abomasum is also visible from the left and right paramedian areas. It appears as a heterogeneous, moderately echoic structure with echogenic stippling. The abomasal folds appear as prominent echoic bands in about two thirds of all goats. The small and large intestines are examined on the right from the 8th to the 12th ICSs. Loops of jejunum and ileum are seen mainly in cross-section and have a strong motility. The intestinal content is usually homogeneous and echoic and the diameter of the intestinal loops varies from 0.8 and 2.7 cm. The spiral colon and in many cases also the caecum can be imaged. The former is recognized by its garland-like appearance brought about by the centripetal and centrifugal coils of the intestine. In the spiral colon and the caecum, only the wall closest to the transducer can be imaged because of intraluminal gas. The wall appears as a thick echoic and slightly undulating line 5.6 to 8.0 cm in length. Ultrasonography is an imaging technique that is very well suited for the examination of the gastrointestinal tract of goats.

A Novel Method for Transcranial Doppler Microembolic Signal Monitoring at the Vertebrobasilar Junction in Vertebral Artery Dissection Patients

Vertebral artery dissection (VAD) is one of the most important etiologies in young stroke patients. VAD causes ischemic stroke by embolism and transcranial Doppler (TCD) monitoring can detect microemboli originating from the dissection point as high intensity transient signals (HITS). We developed a simple but novel method of TCD monitoring at the vertebrobasilar junction in VAD patients. We placed a Welder TCD headband upside down on the patient's head and rotated it by 90°. Then we fixed a pulsed-wave 2-MHz TCD probe to the headband and put it on the suboccipital paramedian area of the patient. With a patient in the lateral decubitus position, the vertebrobasilar junction was identified at a depth of approximately 80 mm. We examined 11 patients with VAD and detected HITS in 2 patients (18%). In 1 patient HITS disappeared after heparinization, and in the other patient HITS disappeared after treatment with aspirin. All of 9 HITS-negative patients and 1 of 2 HITS-positive patients experienced no ischemic recurrence during hospitalization. We successfully detected HITS at the vertebrobasilar junction in VAD patients, which may lead not only to an appropriate choice of antithrombotic drugs but also to individual evaluation of early risk of ischemic recurrence.