Course Of Canal Research Articles

A morphological study of the multi infraorbital canals of the maxilla in the Japanese macaque by cone-beam computed tomography

The infraorbital canal in the Japanese macaque is composed of main and accessory canals. However, the morphological features of the infraorbital canal, such as the canal course and the supply of infraorbital vessels and nerves in the maxilla, are poorly characterized. In this study, we show the structure of the infraorbital canal of the Japanese macaque (adults; 10 male, 9 female), including the distribution of these vessels and nerves, using cone-beam computed tomography and a macroscopic apparatus. The superior and lateral margins of the orbit were correlated with the infraorbital canal on three-dimensional reconstruction images (P<0.05). We classified three types of multi infraorbital foramina as follows: type 1 had one accessory foramen, type 2 had two accessory foramina, and type 3 had three accessory foramina in the infraorbital canal. The infraorbital canal also formed three structures, specifically, a tube-like shape, a funnel shape, and a pinched shape. The accessory canals also contained nerves and blood vessels, and the canals ran downward and supplied the maxillary sinus, teeth, and midfacial region of the craniofacial skeleton, while passing through a few branch canals. These accessory canals proved valuable for blood vessels and nerves and allowed us to recognize the maxilla in the Japanese macaque skull.

Lipomas of the cerebellopontine angle and internal auditory canal

To describe the presentation and clinical course of cerebellopontine angle (CPA) and internal auditory canal (IAC) lipomas. Retrospective cohort study at a tertiary academic referral center. All patients presenting with a CPA or IAC mass radiographically consistent with a lipoma on high-resolution magnetic resonance imaging (MRI) were identified. Data including presenting symptomatology, tumor characteristics, management strategy, and patient course were collected. Between 1996 and 2012, 15 patients were diagnosed with a CPA or IAC lipoma at the authors' institution and were included in the analysis. The mean duration of radiological and clinical follow-up was 3.4 years and 5.1 years, respectively. Eight lesions were confined to the IAC, while seven involved the CPA. The median tumor size at diagnosis was 7.2 mm; one patient demonstrated tumor growth on serial MRI while the remaining subjects did not have radiological progression. The most common presenting symptoms were sensorineural hearing loss (40%) and tinnitus (33%); five patients were diagnosed after incidental discovery on MRI. Fourteen patients were managed with observation, while one subject underwent subtotal resection. None of the observed patients reported worsening symptoms at last follow-up. While rare, lipomas should be included in the differential diagnosis of CPA and IAC lesions. Owing to a generally benign clinical course and high morbidity associated with resection, microsurgery should only be considered in cases of definite tumor enlargement with intractable symptoms from mass effect. Careful radiological evaluation is critical for establishing an accurate diagnosis in order to prevent unnecessary morbidity associated with resection.

El-Salam canal is a potential project reusing the Nile Delta drainage water for Sinai desert agriculture: Microbial and chemical water quality

More than 12×109m3/year of Nile Delta drainage water is annually discharged into the Mediterranean Sea. El-Salam (peace) canal, having a mixture of such drainage water and the Nile water (1:1 ratio), crosses the Suez canal eastward to the deserts of north Sinai. The suitability of the canal water for agriculture is reported here. Representative samples were obtained during two successive years to follow effects of seasonal and spatial distribution, along the first 55km course in north Sinai, on the water load of total bacteria, bacterial indicators of pollution, and chemical and heavy metals contents. In general, the canal water is acceptable for irrigation, with much concern directed towards the chemical contents of total salts (EC), Na and K, as well as the trace elements Cd and Fe. Extending the canal course further than 30km significantly lowered the fecal pollution rate to the permissible levels of drinking water. Results strongly emphasize the need for effective pre-treatment of the used drainage water resources prior mixing with the Nile water.

CT anatomy of the anterior superior alveolar nerve canal: a macroscopic and microscopic study

The aims of this study were to confirm the course of the anterior superior alveolar nerve (ASAN) canal in maxillary bone on CT images and to clarify the components of its contents to provide new evidence for neurovascularization of the anterior jaw bones. The heads and two jaw bone specimens (maxillae) of three formalin-perfused cadavers were examined. The ASAN canal course was verified on cone-beam computed tomography (CBCT) images of the heads. Subsequently, the canal structures branching from the inferior orbital canal were dissected macroanatomically and compared with the CBCT images. Microanatomically, the ASAN canal was visualized in two bone specimens from the infraorbital region using micro-computed tomography (micro-CT). To verify the micro-CT findings, each specimen was sectioned for comparison with the histological observations. The gross anatomy revealed close correspondence between the course of the ASAN canal on CBCT images and that of the neurovascular bundle dissected from the canal structures branching from the inferior orbital canal. Microscopically, it was verified on micro-CT images that the ASAN canal contained neurovascular bundles including nerve bundles, arteries, and veins. We confirmed that the canal-like structure in the anterior maxillary bone on CT images is the ASAN canal. It should be noted that the ASAN canal is filled with neurovascular structures. The present findings may provide useful information for clinicians assessing potential risks prior to anterior jaw bone surgical procedures.

Moving an incisor across the midline: A treatment alternative in an adolescent patient

A 13-year-old sought treatment for a severely compromised maxillary left central incisor and an impacted fully developed left canine. Extraction of both teeth became necessary. As the key component of the revised comprehensive treatment plan, the right maxillary central incisor was moved into the position of the left central incisor. All other maxillary teeth were moved mesially to close any gaps. Active orthodontic treatment was completed after 34 months. Frenectomy, minor periodontal surgeries, and bonded lingual retainers were used to improve aesthetics and stabilize the tooth positions. The patient was pleased with the treatment outcome. Cone-beam computed tomography provided evidence that the tooth movement was accompanied by a deviation of the most anterior portion of the median palatine suture. This observation may make relapse more likely if long-term retention cannot be ensured. Root resorption was not observed as a consequence of the major tooth movement.

A refined hydro-environmental watershed model with field-plot-scale resolution

A distributed hydro-environmental model is developed that achieves detailed analysis of the movement of water at a field-plot-scale resolution in a mesoscale watershed including lowland areas where, especially for agricultures, it is an essential need to get rid of redundant groundwater by drainage facilities such as rivers, canals and/or underdrains. For this, the problem geometry is meshed with unstructured cells of triangular shape. Profile of a column cell is zoned into two: surface zone and groundwater zone in which water movement is represented by combined tank and soil moisture sub-models, and well-defined two-dimensional unconfined shallow groundwater flow sub-model, respectively. The top-two sub-models serve to evaluate evapotranspiration, infiltration, soil water content, lateral surface water flow, and vertical percolation. The vertical percolation so evaluated is given as longitudinal recharge to the bottom sub-model for computing groundwater flow. Surface water–groundwater interactions through beds and stream-banks of perennial and ephemeral canals are considered by treating the canal courses as internal boundaries in the groundwater flow model. The finite volume method (FVM) that allows of unstructured mesh and produces conservative solutions is employed for groundwater flow computation. The model developed is applied to an actual watershed which includes a low-lying paddy area to quantify the hydrological impact of land-use management practices over a period of 29 years in which the farmland consolidation project was implemented and part of the paddy fields were converted to upland crop fields and housing lands. From the results obtained, it is concluded that the model presently developed lends itself to water—as well as land-use management practices.

Results of the modified trabeculotomy in the treatment of primary congenital glaucoma

Purpose: To evaluate the effect of trabeculotomy employing probes with curvatures more closely corresponding to variable course of Schlemm's canal. Methods: Forty-six children with primary congenital glaucoma who underwent trabeculotomy with newly designed probes between 1990 and 1998 were evaluated retrospectively. One set of the newly designed instruments consists of 3 pairs of trabeculotomy probes, the curvatures of which correspond to corneal diameters of 10, 12, and 14 mm. The criteria for surgical success were intraocular pressure (IOP) below 21 mmHg and simultaneous absence of cup to disc (C/D) ratio progression and of disproportional enlargement of the cornea. Results: Forty-six children who underwent surgery over the course of 7 years were evaluated in a follow-up period from 7 to 83 months (38.4 ± 22.5 months). A total of 102 trabeculotomies were performed in a total of 78 eyes, with the following complications: 8 large intraoperative hemorrhages, 3 small iris prolapses, 2 small descemetolyses, and 1 short iridodialysis. Postoperatively, glaucoma was successfully controlled in 68 eyes (87%), IOP fell in average from 30.81 ± 6.55 mmHg to 16.32 ± 5.13 mmHg (P <.00005). Visual acuity was better than 0.4 in 50 eyes and worse than 0.1 in 5 eyes at the end of the study. Conclusion: The probing of the Schlemm's canal was feasible in all procedures and the number of complications was low. The success rate of surgery was high. Adaptation of the trabeculotomy probes to the Schlemm's canal curvature seems to make probing easier and safer. (J AAPOS 2002;6:182-6)

A new species of Rosacea (Siphonophora: Calycophorae: Prayidae) from the Gulf of Oman

A new species of the genus Rosacea (Siphonophora: Calycophorae: Prayidae) is described from the Gulf of Oman, where its eudoxid stage was found in abundance. It is distinguished from other Rosacea species by the course of the lateral radial canals on the nectosac of the nectophore, and the shape of the eudoxid bract and the arrangement of its bracteal canals.

The Sensory Canal Systems of the Living Coelacanth, Latimeria Chalumnae: A New Instalment

Entire sensory canal systems of the coelacanth, Latimeria chalumnae, are described: not only the course of principal canals with their primary and secondary collaterals, but also the course and branches of the pit-line and reticular canals. The number of pores on the left side of the head were found to be 296 in an early (yolksac) embryo, 321 in a late term fetus, 485 in a juvenile, and 2974 in adults. This means that in latimeria most of the lateral-line canal system develop after parturition. Pit lines of the living coelacanth are not rows of superficial neuromasts but canals covered by a thin epidermis like in other sensory canals of the lateral line. These pit-line canals, however, have a very specific structure and branching pattern: the medial dorsal pit-line canal is connected by fine branches on top of the head. The infra-dentary pit-line canal connects via these branches with canals deep inside the bones. Several fine and richly branched canaliculi of unknown function radiate from each quadratojugal pit-line canal. The gular plate pit-line canal has superficially branching arms as well as connections to numerous deeper canals inside the bone. These canals consist of fine branches that in turn lead to and open on the ventral surface of the gular plates as small pores. The system is reminiscent of the reticular (pore) canal system known only from some fossil agnathans and fishes. Thus latimeria combines the reticular system of ancient vertebrates with the lateral-line system of modern fishes. The significance of this gular (possibly electro-sensory) system for feeding by the coelacanth will be discussed.

Surgical anatomy of the anterior ethmoidal canal in ethmoid roof.

This study was undertaken to examine three main relationships. First, the distance and angle from the anterior ethmoidal canal to the limen nasi and the sill were measured. Second, the location of the anterior ethmoidal canal was examined in relation to the lamellas and the skull base. Third, the existence of bony defects in the canal and the course of the canal through the anterior cranial fossa were studied. This study employed both sagittal computed tomography and cadaver dissection. Seventy sagittally divided heads from randomly chosen Korean adult cadavers were used. Sagittal computed tomography was performed on all specimens. Then they were meticulously dissected under a surgical microscope. The mean distance and angle between the limen nasi and the anterior ethmoidal canal were 49.0 mm and 54.5 degrees, respectively. The anterior ethmoidal canal was located between the second and third lamella in 61 of 70 cases. In 60 of 70 cases it was attached to the base of the skull, and in the remaining 10 cases it ran 2 to 3 mm below the skull base. When viewed from the superior side, the course of the anterior ethmoidal canal formed a diagonal line from the lateral to the medial side. Partial bony defects of the anterior ethmoidal canal were observed in eight cases, and complete bony defects in none. This study provides surgeons with a better understanding of the anatomy of the anterior ethmoidal canal.

Spatial orientation of semicircular canals and afferent sensitivity vectors in pigeons.

Rotational head motion in vertebrates is detected by the semicircular canal system, whose innervating primary afferent fibers carry information about movement in specific head planes. The semicircular canals have been qualitatively examined over a number of years, and the canal planes have been quantitatively characterized in several animal species. The present study first determined the geometric relationship between individual semicircular canals and between the canals and the stereotactic head planes in pigeons. Stereotactic measurements of multiple points along the circumference of the bony canals were taken, and the measured points fitted with a three-dimensional planar surface. Direction normals to the plane's surface were calculated and used to define angles between semicircular canal pairs. Because of the unusual shape of the anterior semicircular canals in pigeons, two planes, a major and a minor, were fitted to the canal's course. Calculated angle values for all canals indicated that the horizontal and posterior semicircular canals are nearly orthogonal, but the anterior canals have substantial deviations from orthogonality with other canal planes. Next, the responses of the afferent fibers that innervate each of the semicircular canals to 0.5 Hz sinusoidal rotation about an earth-vertical axis were obtained. The head orientation relative to the rotation axis was systematically varied so that directions of maximum sensitivity for each canal afferent could be determined. These sensitivity vectors were then compared with the canal plane direction normals. The afferents that innervated specific semicircular canals formed homogeneous clusters of sensitivity vectors in different head planes. The horizontal and posterior afferents had average sensitivity vectors that were largely co-incident with the innervated canal plane direction normals. Anterior canal afferents, however, appeared to synthesize contributions from the major and minor plane components of the bony canal structure to produce a resultant sensitivity vector that was positioned between the canal planes. Calculated angles between the average canal afferent sensitivity vectors revealed that direction orthogonality is preserved at the afferent signal level, even though deviations from canal plane orthogonality exist.

Three-dimensional computer-aided reconstruction and measurement of the temporal bone for singular neurectomy.

A computer reconstruction method was used to study five normal temporal bones for the three-dimensional anatomy necessary for singular neurectomy. The length of the singular canal was 4.9 +/- 0.6 mm. The distal portion of the singular canal courses at a sharp angle (48.2 degrees) to the direction of the transmeatal surgical approach for this operation. The reconstructions indicated that the singular canal can be exposed by introducing a drill through the external auditory meatus at a point 0.71 mm posteroinferior to the posteromedial margin of the round window on the saucerized medial wall of the round window niche. The distance from this site to the distal end-portion of the singular canal averaged 1.47 mm. The point on the drilling course (from the drilling site to the singular canal) closest to the vestibular end of the hook portion of the cochlea was 0.48-1.00 mm from the drilling site. The reconstructions also indicated that the dissection should proceed superomedially, if necessary, after a 1-mm-deep straight dissection along the transmeatal approach. The ampulla of the posterior semicircular canal, cochlear aqueduct and inferior cochlear vein were all found to lie within 2 mm of the drilling point.

Arthroscopy of the temporomandibular joint: An anatomic perspective

Anatomic relationships in the temporomandibular joint (TMJ) region related to arthroscopic surgery were analyzed in cadaver dissections and dry skulls. The study showed that the maxillary artery and the main bifurcation of the facial nerve are located a safe distance from the usual arthroscopic approaches to the TMJ. The frontal branch of the facial nerve are located a safe distance from the usual arthroscopic approaches to the TMJ. The frontal branch of the facial nerve may be as close as 3 mm anterior to the midpoint of the lateral pole of the condyle. The neurovascular complex of the superficial temporal vessels and the auriculotemporal nerve may also be very close to puncture sites. The roof of the glenoid fossa had an average thickness of 0.9 mm. The external soft tissue auditory canal courses anteriorly to meet the bony external auditory canal. A skin puncture perpendicular to the bony canal was approximately 7 mm anterior to the posterior aspect of the tragus.

A crustacean statocyst with only three hairs: Light and scanning electron microscopy.

Standard histological and SEM techniques have been used to examine the pair of statocyst organs located in the telson of the isopod, Cyathara polita. Each organ is formed as an invagination of the dorsal cuticle of the telson. The invagination narrows to form a stalk between the statocyst and dorsal surface. A canal courses longitudinally through this stalk and forms a continuous channel between the lumen of the cyst and the external environment. On the luminal floor of each statocyst, there are three pits; each correlates with a nodule protruding from the ventro-medial wall. From each pit, a single, bifurcating hair projects dorsally to contact the single concretion within the statocyst lumen. No other static organs have been found in this animal. Thus, maintenance of equilibrium in this species appears to be under the control of but six hairs, three in each statocyst. Innervation of each statocyst is provided by a branch of a nerve which connects anteriorly with the last abdominal ganglion.

The course of resin canals in the shoots of conifers

Resin canal patterns in the Pinaceae differ significantly from those in other conifers. In this paper, Pinus type, Picea type and Larix type are defined.Pinus has the Pinus type pattern, in spite of the possession of a system of peripheral canals in some members. The patterns inAbies, Picea, Cedrus, Keteleeria andPseudotsuga are varied. Both Pinus and Picea types are usually observed, although many other types are also seen in these five genera.Larix andPseudolarix have the Larix type pattern, andTsuga has a modified Torreya type pattern.From the data obtained in the present series of studies (Suzuki, 1979a, b), two main evolutional trends of resin canal patterns are suggested. In the Pinaceae, the patterns probably evolved from the complicated type to the simple type. In the other families, they evolved from the simple type to the complicated type. Moreover, it is to be considered likely that the patterns have evolved independently in each family.Patterns of resin canals are very similar to the primary vascular patterns. The similarity is probably not fundamental, but superficial, because most of the conifer species, of which resin canal patterns are varied, have but a single type of the primary vascular system.

The course of resin canals in the shoots of conifers

The course of resin canals in stem cortex and the continuity between resin canals in leaves and those in stem cortex were investigated. The present paper is the first of three parts of the investigation. In this paper, fundamental features of resin canals and actual resin canal patterns in the Taxaceae, Cephalotaxaceae and Podocarpaceae are reported. From the observation of serial transections of shoots, composite diagrams and three-dimensional models of resin canal patterns are drawn. Central canals, if present, run vertically in stem cortex and sometimes divide, end blindly or unite each other. The distance between two adjacent central canals fluctuates rhythmically in connection with the vascular supply from the stem to leaves. The resin canal patterns of the families are classified into four types. Those ofTaxus, Nothotaxus and three species ofDacrydium belong to the Taxus type, those ofTorreya andCephalotaxus to the Torreya type, those ofDacrydium elatum, Podocarpus alpinus, P. elatus, P. elongatus andP. neriifolius to the Dacrydium type, those ofP. macrophyllus, P. nagi andP. koordersii to the Podocarpus type.

The course of resin canals in the shoots of conifers

The course of resin canals in the shoots of conifers

The course and incidence of multiple canals in the mesio-buccal root of the maxillary first molar.

The course and incidence of multiple canals in the mesio-buccal root of the maxillary first molar.

RADIOLOGICAL EXAMINATION OF TEMPORAL BONE IN INFANTS AND CHILDREN.

Recent advances in otologic surgical technics, involving the use of an operation microscope, have led to increased demands in respect to the radiologic examination of the temporal bone, especially during childhood. The conventional methods—the Schuller, Stenver, Runstrom, Towne, and Chausse projections—often afford information only regarding pneumatization and inflammatory processes, but seldom demonstrate changes of the ossicles or the labyrinth. Tomography has brought about a fundamental change in this state of affairs, enabling us to visualize the minute details in the tympanic cavity, such as the ossicles, the cochlea, the intratemporal course of the facial canal, and the semicircular canals. At the Copenhagen County Hospital in Gentofte, we have used the Massiot polytome, which, by virtue of its hypocycloidal movements, effectively eliminates the structures outside the plane of the cut and makes possible cuts as thin as 1 mm. Various projections have been used for tomography of the temporal bone (6)....

A Reappraisal of Hohokam Irrigation1

For over two centuries the visible remains of prehistoric irrigation in southern Arizona have been the subject of scrutiny and speculation. Manje, for example, in the company of Father Kino, recorded his observations of the canals near Casa Grande and along the Santa Cruz River at the end of the 17th century (Karns 1954:135, 141, 287). In the 19th century many keen observers, such as General Rusling (1877), were impressed by what they could see and could infer about the canals. Systematic investigations began with Cushing in 1887, when the Hemenway Expedition cut a cross section through the canal that they found at Los Muertos (reported by Hodge in 1893), and prepared a map of the canals leading from the Salt River to the vicinity of Los Muertos (published by Haury, 1945a), that appears to consist of about equal parts of observation and imagination. A more satisfactory map, and one of a larger area, was published by Patrick in 1903, becoming the basis for Turney's map of 1922 and its later editions through 1929. Turney also published (1929-30) a lengthy but unorganized collection of quotations, observations, and speculations concerning the ancient canals of the Salt Valley. The first map of the Gila River canals was published in 1926 by Cummings. In 1930 an ambitious and systematic program of aerial photography of parts of both the Gila and Salt was directed by Judd (1931) with assistance from Halseth (1936)-a program that unfortunately was never completed and published, although the photographs and notes are currently on loan to the Arizona State Museum, where they are receiving further study. Excavation of prehistoric canals has lagged behind mapping and surface observations, so that only the two cross sections dug by Haury at Snaketown (Haury 1937) have been available as a basis for correcting the many guesses made about the size and form of the canals. In general, three kinds of information are needed for a proper understanding of Hohokam irrigation: (1) details such as size, profile, gradient, and course of individual canals; (2) chronological data-dates of initial construction and length of use; and (3) the location and extent of the several canal systems. All of this information will be most useful, of course, when combined with the slowly emerging picture of Hohokam culture history. But details of the ancient canals are scanty and will remain so, since the places anciently irrigated have been highly attractive to modern farmers ever since the first settlement of Phoenix in 1867. In 1903 Patrick wrote that . .. the greater portion of the ruins of the ancient canal systems have long since been leveled by the agriculturalist. The situation is far worse now than Patrick could have imagined. Nevertheless, a few facts are available,