Studies of anterior and posterior paranasal sinuses

To the anterior paranasal sinuses are the frontal and maxillary sinuses, as well as the front cells of the latticed labyrinth.

Nosopodbordochnaya laying (supraoksipito-alveolar projection); allows you to receive the following data:

• Frontal sinuses are usually located symmetrically, separated by bone septa, one of which is paramedic; normal negative radiographic imaging should be dark gray, somewhat lighter than orbits, homogeneous within well-defined bone boundaries, displayed as a white continuous line;
• orbits are slightly flattened due to the corresponding projection, in the lower lateral part of them the shadows of the wings of the sphenoid bone are visible;
• The cells of the latticed labyrinth and their bony septa are projected between the orbits; the posterior cells of the latticed labyrinth, for this laying, seem to continue the front cells and are visualized in the direction (indicated by the arrow) to the upper medial angle of the maxillary sinus;
• the maxillary sinuses located in the center of the facial massif are the most symmetrical in localization and approximately the same in shape and size; sometimes inside the sinuses there are bone septa (full and incomplete), which divide the cavity into two or more parts; these septa are well visualized on radiographs; great importance in the diagnosis of diseases of the upper respiratory tract has X-ray visualization of its pockets (alveolar, lower, molar and ophthalmic-trellised), each of which can play a role in the development of diseases of the paranasal sinuses;
• The lower glottis slit, through which the zygomatic and lower nostrils emerge, is projected under the lower edge of the orbit; it is important in the conduct of local-regional anesthesia, and with its deformation - in the emergence of neuralgia of the corresponding nerve trunks;
• a circular aperture is projected in the mid-medial part of the planar image of the maxillary sinus (on the roentgenogram it can be clearly seen in the form of a rounded black point surrounded by dense bone walls) and always adjacent to the image of a wedge-shaped fissure.

Nosolobnaya stacking (supraoccipitofrontalnaya projection) allows you to get a detailed image of the frontal sinuses, eye sockets and cells of the trellis labyrinth.

In this projection, the cells of the latticed labyrinth are visualized more clearly, but the dimensions and lower sections of the maxillary sinus can not be fully visible because they are projected on the pyramids of the temporal bones. It should be noted that with this stowage, despite the good visualization of cells of the latticed labyrinth, many shadows of other anatomical forms of the skull are layered on their image. A distinctive feature of these formations is that their shadows spread without interruption beyond the cells of the trellis labyrinth. The main purpose of nosolobnoy projection - is to obtain an expanded image of the frontal sinus.

Lateral folding allows visualizing the frontal sinus, its front and back walls, possibly - and the interstitial septum; the base of the nose and the nasal bones; the front cells of the latticed labyrinth; the outer edge of the orbit, which passes to its upper edge upward, and downwards to the lower edge; maxillary sinus and its walls in the sagittal section; a solid sky and an alveolar arch with molars in it; frontal process of the malar bone; the middle part of the trellis, located between the contour of the outer margin of the orbit in front and the apophysis of the zygomatic bone posteriorly; arch of orbit; grating plate; cervical spines; the front arch of the atlant and a number of other formations.

The outlines of the visualized formations are often represented as double lines due to the superposition of both halves of the face skeleton. The sphenoid sinus is projected under the Turkish saddle. The lateral projection is important if it is necessary to evaluate the shape and size of the frontal sinus in the anteroposterior direction (for example, if it is necessary to trepanopuncture it), determine its relation to the orbit, the shape and size of the wedge and maxillary sinus, as well as many other anatomical formations of the facial skeleton and anterior parts of the skull base .

Examination of the posterior (craniobasilar) paranasal sinuses

The posterior paranasal sinuses include the sphenoid sinus; some authors topographically refer to these sinuses and the posterior cells of the latticed bone.

Axial projection (vertexosubmental) reveals a variety of skull base formations; if necessary, visualize the sphenoid sinus, the rocky part of the temporal bone, the skull base holes and other elements. This projection is indicated for fractures of the base of the skull. In this projection, the following anatomical elements are visualized: frontal and maxillary sinuses; lateral walls of the latter and orbits; the body of the malar bone (lower arrow); posterior edge of small wing of sphenoid bone; cells of the trellis, located along the middle line, sometimes covered with hypertrophic middle nasal shells.

The sphenoid sinuses are distinguished by a considerable variety of structure; Even in the same person, they can be different in volume and asymmetric in location. They can be from a very small to an extremely large image and spread to the surrounding parts of the sphenoid bone (large wings, pterygoid and basilar apophyses).

In addition, some holes in the base of the skull (oval, circular, front and rear lacerated holes) are visualized in this projection, through which the fracture line often passes through the trauma of the skull (falling on the head, knees, blows along the crown and occipital bone). The shadows of the part of the pyramid of the temporal bone and its apex, the mandibular branch, the apophysis of the base of the occipital bone, the atlas and the large occipital foramen, in which the shade of the 2nd cervical vertebra of the tooth is visible.

In addition to the above standard projections used for radiographic examination of the paranasal sinuses, there are a number of other folds that are used when it is necessary to enlarge and more clearly identify any one anatomotopographic zone.

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