الفهرس 
Anatomy of the noseOnly 14 pages are availabe for public view
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Abstract
The deviated nose deformity remains one of the most difficult problems encountered by the facial plastic surgeon. Contributions to the deviation often exist from the nasal septum, bony and cartilaginous dorsum, and even nasal tip.
In order to understand the deviated nose, a Plastic Surgeon must understand thoroughly the anatomy of the nose.
There are significant nasal architectural differences between racial groups. On examination there are great variations considering nasal aperture and Alar base, differing from Chinese, Indian and Caucasian race.
Also the anatomic feature of the nose in different races contributes in its chance to get traumatized. Another factor that contributes in same issue is the age of the patient, as young ages and the elderly suffer less than mid aged adults. Concerning gender affection we find that males are affected more than females.
Considering the causes of deviated nose there are many causes but the most important one is trauma. Other causes might include congenital, infection, neoplastic or even iatrogenic causes.
Certain risk of recurrence is always present, despite the numerous surgical techniques described in the literature to correct the nasal structures involved in this deformity. This complication is derived from the intrinsic and extrinsic dislocating forces of traction, which tend to deviate the middle and lower third of the nasal pyramid again. The intrinsic force consists of the cartilage memory of the nasal septum, which tends to bring the septum back to its original position. The extrinsic forces are instead primarily determined by the upper lateral cartilages, which are deformed and asymmetric, arching outward on the convex side and inward on the concave side.
The first step in correcting the deviated nose is to make a careful anatomic diagnosis through a good physical evaluation and careful study of facial aesthetics. The nose should be examined in light of overall facial asymmetry.
At times the entire lower two-thirds of the face deviates to one side which can be visualized by holding a vertical rule from the midpoint of the nasion to the midpoint of the upper lip and teeth. This deviation must be recognized because not only will it prevent complete straightening of the nose, but may lead to a less aesthetically desirable outcome if attempted. The entire nose should be palpated including the bony dorsum to determine length of nasal bones and point of deviation as well as the nasal septum and nasal spine. Additionally, the tip recoil should be estimated by depressing the nasal tip in order to assess the existing tip support.
The nose may be addressed by a variety of surgical techniques depending upon surgeon preference and nasal deformity; however several areas of common pitfall exist including important deviations in the caudal and dorsal septum as well as irregularities of the ULCs.
Prior to shifting the bony vault back to the midline, the dorsal profile must be assessed for hump removal. Care must be taken in removing the hump however because of the vertically oriented position of one of the nasal bones. When removing the bony dorsum often less bone removal is required from the vertically oriented nasal bone to produce symmetry once osteotomies are complete. Often times, nasal bones are markedly asymmetrical in their appearance with one being concave and the other convex. In these instances intermediate osteotomies may need to be carried out to straighten the bones. In these cases extra care must be taken not to elevate the periosteum off the nasal bones to prevent their collapse into the nasal vault.
In most deviated noses, the lower two thirds of the nose are at least partially involved in the deformity. In these cases the ULCs should be freed from the anterior dorsal border of the nasal septum to allow these structures to reorient themselves in the midline. If reorientation of the lower two thirds of the nose is not performed, after osteotomies the nose may shift back toward the preoperative orientation and heal in a crooked position because of the memory of the deviated cartilaginous structures.
Following division of the ULCs care must be taken to prevent the ULC from collapsing infero-medially and obstructing the nasal valve. This can be prevented by leaving the mucosa attached to the underside of the ULC and by taking care to re-secure the cartilage to the septum upon completion. These maneuvers are best accomplished through an open approach to the nose and septum. This technique is also beneficial because it affords adequate visualization of the dorsal aspect of the septum which is often deviated and may contribute to persistent postoperative deviation.
If only a minor deviation exists the nose may shift to the midline following osteotomies with little difficulty. In some cases, a significant residual deviation of the dorsal border of the nasal septum will be present.
These deformities may be isolated or involve the entire cartilaginous septum. In many cases, there is some form of a C-shaped deformity creating a dorsal concavity on one side of the nose and a convexity on the opposite side. If the caudal septum is in the midline, camouflaging techniques can be used to correct mild to moderate C-shaped deformities of the dorsal septum. The convex side of the septum may be shaved and the concave side have a unilateral spreader graft placed. The graft should be slightly larger than the defect to allow for changes in the ipsilateral ULC. The ULCs can then be re-sutured to the spreader graft and septum and the SSTE replaced.
The caudal margin of the septal cartilage is very important because it provide support for the lower third of the nose via attachment to domes and medial crura. Caudal deviations must be corrected for support purposes as well as for correction of airway obstruction.
Relatively minor caudal septal deviations can be corrected by using cartilage manipulation and suturing techniques. If the anterior septal angle is in good position and only the posterior septal angle has been shifted off the nasal spine, a small triangular piece of septum may be trimmed, the concave side lightly crosshatched and then sutured to the periosteum on the opposite side of the nasal spine. With placement of this suture care must be taken not to pull down on the posterior septal angle which could result in a decrease in nasal tip projection. Severe caudal septal deviations may require replacement of the deformed segment of the nasal septum with a straight piece of cartilage, what is called extension caudal graft.
When the caudal septum, anterior septal angle, or a significant portion of the L-shaped strut is severely deviated or fractured, replacement of the deformed segment of nasal septum can be performed, and if necessary the entire strut may be refashioned. The replacement L-shaped strut must be re-sutured to a stable cartilage remnant at the rhinion and nasal spine. Positioning of the medial crural footplates onto the new caudal strut can affect tip rotation and nasal length. To add additional tip support a sutured-in-place columellar strut may also be placed.
Any further deviations or irregularities may be corrected with onlay camouflage grafts. This technique is very useful for camouflaging the C-shaped deformity of the dorsal septum, but it does not correct for the underlying deviation. With larger C-shaped deformities thin ethmoid bone can be harvested from the septum and cut into rectangular grafts to splint the deviated (concave) side.
The septal cartilage may be lightly cross-hatched on the concave side to release the memory and the ethmoid bone grafts sutured on either side using a large Keith needle to drill holes, therefore stenting the septum into a straight orientation. Once all of the grafts are in place the anterocaudal-most corner of the ULC must be sutured to the region near the anterior septal angle to prevent collapse.
In modern times, autologous grafts for the nasal dorsum won general acceptance. Among them the primary choices are septal, conchal, and rib cartilage. Unfortunately, it is presently impossible to obtain an autogenic cartilage graft in the size and shape desired in every case. Alloplastic materials currently offered are generally well tolerated.
However, they must be implanted completely without tension or pressure on the overlying tissues, which might cause ischemia and necrosis. For this reason, their implantation in the lower two thirds of the nose presents a perilous situation because the lower two fifths of the nose are in continuous motion. Soft Silastic, Gore-Tex, Proplast, and coralline hydroxyapatite grafts have sometimes yielded satisfactory long-term results. Their advantages are that they can be factory preformed, and supplied sterile and are easy for instant use. Further, there is no donor-site morbidity, they are easy to place, and they usually produce a smooth straight nasal contour. Their disadvantages that they may be accompanied by infection in the picture of AIDS or hepatitis.
Also, HDPP has a more than 20 years history as a surgical implant in both animals and humans. PDS foil is another alloplastic material that is a resorbable material, degradable by hydrolysis and completely metabolized in the body, and has been used successfully for years to reconstruct bone defects, for example, in orbital floor reconstruction. It has been used recently as resorbable supporting material for the cartilaginous septum.
Scion Image is a freeware computer program. Using this program is greatly helpful in evaluating the effectiveness of surgical techniques and the results for correction of deviated noses in an objective manner. Besides deviation angles, other measurements including nasofacial, nasofrontal, and nasolabial angles can be performed using Scion Image.
Conclusion:
Deviated nose is one of the challenging cases that face plastic surgeons. After knowing the anatomy, cause of deviation & variability of noses, the right choice of surgery is done to the patient.
The deviated nose deformity remains one of the most difficult problems encountered by the facial plastic surgeon. Contributions to the deviation often exist from the nasal septum, bony and cartilaginous dorsum, and even nasal tip.
In order to understand the deviated nose, a Plastic Surgeon must understand thoroughly the anatomy of the nose.
There are significant nasal architectural differences between racial groups. On examination there are great variations considering nasal aperture and Alar base, differing from Chinese, Indian and Caucasian race.
Also the anatomic feature of the nose in different races contributes in its chance to get traumatized. Another factor that contributes in same issue is the age of the patient, as young ages and the elderly suffer less than mid aged adults. Concerning gender affection we find that males are affected more than females.
Considering the causes of deviated nose there are many causes but the most important one is trauma. Other causes might include congenital, infection, neoplastic or even iatrogenic causes.
Certain risk of recurrence is always present, despite the numerous surgical techniques described in the literature to correct the nasal structures involved in this deformity. This complication is derived from the intrinsic and extrinsic dislocating forces of traction, which tend to deviate the middle and lower third of the nasal pyramid again. The intrinsic force consists of the cartilage memory of the nasal septum, which tends to bring the septum back to its original position. The extrinsic forces are instead primarily determined by the upper lateral cartilages, which are deformed and asymmetric, arching outward on the convex side and inward on the concave side.
The first step in correcting the deviated nose is to make a careful anatomic diagnosis through a good physical evaluation and careful study of facial aesthetics. The nose should be examined in light of overall facial asymmetry.
At times the entire lower two-thirds of the face deviates to one side which can be visualized by holding a vertical rule from the midpoint of the nasion to the midpoint of the upper lip and teeth. This deviation must be recognized because not only will it prevent complete straightening of the nose, but may lead to a less aesthetically desirable outcome if attempted. The entire nose should be palpated including the bony dorsum to determine length of nasal bones and point of deviation as well as the nasal septum and nasal spine. Additionally, the tip recoil should be estimated by depressing the nasal tip in order to assess the existing tip support.
The nose may be addressed by a variety of surgical techniques depending upon surgeon preference and nasal deformity; however several areas of common pitfall exist including important deviations in the caudal and dorsal septum as well as irregularities of the ULCs.
Prior to shifting the bony vault back to the midline, the dorsal profile must be assessed for hump removal. Care must be taken in removing the hump however because of the vertically oriented position of one of the nasal bones. When removing the bony dorsum often less bone removal is required from the vertically oriented nasal bone to produce symmetry once osteotomies are complete. Often times, nasal bones are markedly asymmetrical in their appearance with one being concave and the other convex. In these instances intermediate osteotomies may need to be carried out to straighten the bones. In these cases extra care must be taken not to elevate the periosteum off the nasal bones to prevent their collapse into the nasal vault.
In most deviated noses, the lower two thirds of the nose are at least partially involved in the deformity. In these cases the ULCs should be freed from the anterior dorsal border of the nasal septum to allow these structures to reorient themselves in the midline. If reorientation of the lower two thirds of the nose is not performed, after osteotomies the nose may shift back toward the preoperative orientation and heal in a crooked position because of the memory of the deviated cartilaginous structures.
Following division of the ULCs care must be taken to prevent the ULC from collapsing infero-medially and obstructing the nasal valve. This can be prevented by leaving the mucosa attached to the underside of the ULC and by taking care to re-secure the cartilage to the septum upon completion. These maneuvers are best accomplished through an open approach to the nose and septum. This technique is also beneficial because it affords adequate visualization of the dorsal aspect of the septum which is often deviated and may contribute to persistent postoperative deviation.
If only a minor deviation exists the nose may shift to the midline following osteotomies with little difficulty. In some cases, a significant residual deviation of the dorsal border of the nasal septum will be present.
These deformities may be isolated or involve the entire cartilaginous septum. In many cases, there is some form of a C-shaped deformity creating a dorsal concavity on one side of the nose and a convexity on the opposite side. If the caudal septum is in the midline, camouflaging techniques can be used to correct mild to moderate C-shaped deformities of the dorsal septum. The convex side of the septum may be shaved and the concave side have a unilateral spreader graft placed. The graft should be slightly larger than the defect to allow for changes in the ipsilateral ULC. The ULCs can then be re-sutured to the spreader graft and septum and the SSTE replaced.
The caudal margin of the septal cartilage is very important because it provide support for the lower third of the nose via attachment to domes and medial crura. Caudal deviations must be corrected for support purposes as well as for correction of airway obstruction.
Relatively minor caudal septal deviations can be corrected by using cartilage manipulation and suturing techniques. If the anterior septal angle is in good position and only the posterior septal angle has been shifted off the nasal spine, a small triangular piece of septum may be trimmed, the concave side lightly crosshatched and then sutured to the periosteum on the opposite side of the nasal spine. With placement of this suture care must be taken not to pull down on the posterior septal angle which could result in a decrease in nasal tip projection. Severe caudal septal deviations may require replacement of the deformed segment of the nasal septum with a straight piece of cartilage, what is called extension caudal graft.
When the caudal septum, anterior septal angle, or a significant portion of the L-shaped strut is severely deviated or fractured, replacement of the deformed segment of nasal septum can be performed, and if necessary the entire strut may be refashioned. The replacement L-shaped strut must be re-sutured to a stable cartilage remnant at the rhinion and nasal spine. Positioning of the medial crural footplates onto the new caudal strut can affect tip rotation and nasal length. To add additional tip support a sutured-in-place columellar strut may also be placed.
Any further deviations or irregularities may be corrected with onlay camouflage grafts. This technique is very useful for camouflaging the C-shaped deformity of the dorsal septum, but it does not correct for the underlying deviation. With larger C-shaped deformities thin ethmoid bone can be harvested from the septum and cut into rectangular grafts to splint the deviated (concave) side.
The septal cartilage may be lightly cross-hatched on the concave side to release the memory and the ethmoid bone grafts sutured on either side using a large Keith needle to drill holes, therefore stenting the septum into a straight orientation. Once all of the grafts are in place the anterocaudal-most corner of the ULC must be sutured to the region near the anterior septal angle to prevent collapse.
In modern times, autologous grafts for the nasal dorsum won general acceptance. Among them the primary choices are septal, conchal, and rib cartilage. Unfortunately, it is presently impossible to obtain an autogenic cartilage graft in the size and shape desired in every case. Alloplastic materials currently offered are generally well tolerated.
However, they must be implanted completely without tension or pressure on the overlying tissues, which might cause ischemia and necrosis. For this reason, their implantation in the lower two thirds of the nose presents a perilous situation because the lower two fifths of the nose are in continuous motion. Soft Silastic, Gore-Tex, Proplast, and coralline hydroxyapatite grafts have sometimes yielded satisfactory long-term results. Their advantages are that they can be factory preformed, and supplied sterile and are easy for instant use. Further, there is no donor-site morbidity, they are easy to place, and they usually produce a smooth straight nasal contour. Their disadvantages that they may be accompanied by infection in the picture of AIDS or hepatitis.
Also, HDPP has a more than 20 years history as a surgical implant in both animals and humans. PDS foil is another alloplastic material that is a resorbable material, degradable by hydrolysis and completely metabolized in the body, and has been used successfully for years to reconstruct bone defects, for example, in orbital floor reconstruction. It has been used recently as resorbable supporting material for the cartilaginous septum.
Scion Image is a freeware computer program. Using this program is greatly helpful in evaluating the effectiveness of surgical techniques and the results for correction of deviated noses in an objective manner. Besides deviation angles, other measurements including nasofacial, nasofrontal, and nasolabial angles can be performed using Scion Image.
Conclusion:
Deviated nose is one of the challenging cases that face plastic surgeons. After knowing the anatomy, cause of deviation & variability of noses, the right choice of surgery is done to the patient.