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Results for “Anatomic Variation”

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At least 19 recordsLinked to original sources

PubMed1996

Pneumatised superior turbinate: a common anatomic variation?

Anatomic variations are important in preendoscopic CT evaluation of the paranasal sinuses. In this study, we investigated whether the superior turbinate could become pneumatised like the middle turbinate, pneumatisation of which is well-known. Images of 52 patients who underwent CT examination prior to endoscopic sinus surgery and who had normally aerated posterior ethmoidal cells and an unobscured nasal cavity were retrospectively evaluated. The patients were 12-68 years old (median age, 35 years); 28 were women and 24 were men. Pneumatisation of the superior turbinates was graded in two groups as minimal or marked. Pneumatisation was evident in 25 patients (48%). 13 unilateral (25%), 8 bilateral (15%) pneumatisations were detected in the group graded as minimal, whereas 1 unilateral and 3 bilateral pneumatisations were present in the markedly (8%) pneumatised group of patients. Superior turbinates were seemingly aerated through the posterior ethmoid cells. The superior turbinates can be pneumatised as the middle turbinate is a not frequent anatomic variation that should be taken into account in preendoscopic CT evaluation of the paranasal sinuses.

Adolescent↗

PubMed1987

Failure of percutaneous liver biopsy: anatomical variation.

Anatomical variation may result in failure to obtain hepatic tissue at liver biopsy. A patient is reported in whom routine liver biopsy was unsuccessful. Subsequent computed tomography (CT) showed that the right lobe of the liver was partially deficient anteriorly and that the biopsy had caused an intraabdominal haematoma. A technically successful biopsy was subsequently carried out under radiological (CT) guidance. Variations in hepatic anatomy are considered and some conclusions are offered which may both improve the success rate and further reduce the morbidity of routine percutaneous needle biopsy of the liver.

Biopsy↗

PubMed1995

Branches of the tibial nerve: anatomic variations.

Anatomic variations in tibial nerve branches may help explain discrepancies between clinical examination and electrophysiologic tests as to the location of neuronal lesions. Dissection of 20 cadaveric feet (10 pair) along the course of the tibial nerve and its branches confirmed that it bifurcates within 2 cm of the medio-malleolar-calcaneal axis in 90% (18/20) and that it gives off frequent small branches with its accompanying vascular structures. Unlike other studies, however, we found that 60% had multiple calcaneal branches off the tibial nerve and that 20% evidenced previously undescribed accessory innervation to the abductor hallucis muscle from other than the medial plantar nerve.

Foot↗

PubMed2001

Anatomical variations in the internal jugular veins of cancer patients affecting central venous access. Anatomical variation of the internal jugular vein.

PURPOSE: Establishing a reliable central venous access is an important procedure in clinical haematology and oncology. The purpose of this study was to determine how anatomical variations in the internal jugular vein (IJV) and its position in relation to the common carotid artery (CCA) in cancer patients affects external landmark puncture. PATIENTS AND METHODS: In 113 patients with haematological or oncological diseases we examined sonographically potential target regions for placement of a central catheter via the IJV. RESULTS: 36% of our patients showed anatomical variations in the IJV and surrounding tissue. CONCLUSIONS: External landmark puncture may be difficult in a considerable number of patients since the IJV might not be situated in the presumed location anteriorly or laterally to the CCA, or a normal lumen may not be present in approximately 1/3 of cancer patients. This study supports the use of ultrasound-guided techniques for central venous catheters particularly in haematological and oncological patients.

Adult↗

PubMed2006

Numerical variation of the celiac trunk and anatomical variation in origin and course of the dorsal pancreatic artery.

A numerical anomaly of the celiac trunk and anatomical variation in origin, and course of the dorsal pancreatic artery were encountered during a routine upper abdomen dissection of a 62-year-old male cadaver. The aim of this study was to describe a rare celiac trunk and dorsal pancreatic artery variation in detail, which can be a guide and precaution during operative procedures in this region. The abdominal aorta, its branches and the pancreas were cut and removed just above the celiac trunk and below the superior mesenteric artery to investigate the vascular distribution of the pancreas in detail. The celiac trunk divided into the left gastric, hepatic, splenic, and dorsal pancreatic arteries. The anatomical variation of the celiac trunk and splenic artery makes it vulnerable to iatrogenic surgery. Knowledge of the existing aberrations is important in planning and conducting surgical procedures.

Cadaver↗

PubMed2004

[Anatomic variations of the bile ducts: MRCP findings].

PURPOSE: Anatomic variations of intra or extrahepatic bile ducts may be problematic during surgical procedures. Besides iatrogenic trauma of the bile ducts during cholecystectomy, formation of bile duct stones, recurrent pancreatitis, cholangitis and biliary malignancies can be seen. The aim of this study was to evaluate the frequency of anatomic variations of the biliary tree and to present the magnetic resonance cholangiopancreatography (MRCP) findings. MATERIALS AND METHODS: Between July 2000 and April 2004, 581 patients suspected to have pancreatobiliary disease, were referred to our MR unit. Four hundred and seventy-five patients with ages ranging from 22 to 88 (median: 56) were included in the study retrospectively. MRCP was performed on a 1 Tesla MR unit, using phased-array coil for signal detection. Heavily T2 weighted images were obtained with SSFSE technique. Axial and coronal source images and reformatted images were all evaluated together for the possibility of any anatomic variation. RESULTS: Anatomic variations at different levels of biliary tree were found in 115 patients (24.2%). MRCP showed an aberrant right hepatic duct in 23 patients (4.8%), a right posterior hepatic duct in 27 patients (5.7%), trifurcation in 4 patients (0.8%), a long cystic duct in 8 patients (1.7%), a medial cystic duct insertion in 3 patients (0.63%), a low medial cystic duct insertion in 18 patients (3.8%), a short cystic duct in 1 patient (0.2%), a high localized gallbladder in 5 patients (1%), a vascular compression of common hepatic duct in 12 patients (2.5%), a pancreatobiliary junction anomaly in 3 patients (0.63%). Eleven patients had more than one anatomic variation (2.3%). CONCLUSION: MRCP is a useful, rapid, and non-invasive method for demonstrating the anatomy and the variations of the biliary tree. Diagnosis of these anatomic variations prior to surgical procedures may prevent iatrogenic injury to bile ducts.

Adult↗

PubMed2006

The relationship between anatomic variations of paranasal sinuses and chronic sinusitis in children.

CONCLUSIONS: Anatomical variations in the nose and paranasal sinuses are common in children. Due to the absence of a definitive relationship between anatomical variations and sinus disease, local, systemic or environmental factors appear to be more significant in pediatric sinusitis than the anatomic variations. OBJECTIVE: Chronic sinusitis is increasing in the pediatric population. Following the initial reports of functional endoscopic sinus surgery (FESS) for children, the majority of patients undergoing this procedure have experienced improved quality of life. Thus, we need to know the precise anatomy and anatomical variations of the nose, as well as the relationship between such anatomy and chronic sinusitis. PATIENTS AND METHODS: To determine the extent and distribution of disease, as well as associated anatomic abnormalities, computed tomography (CT) scans were performed on 113 children with persistent symptoms of sinusitis after failure of medical therapies. RESULTS: The maxillary sinus was the most commonly involved sinus, followed by the ethmoid, sphenoid, and frontal sinuses. There was no relationship between age and severity of sinusitis. Agger nasi cell was the most common anatomical variation, followed by septal deviation, Haller cell, concha bullosa, paradoxical middle turbinate, and Onodi cell. The prevalence of septal deviation increased with age. There was no significant relationship between the sinusitis and anatomic variations.

Adolescent↗

PubMed2005

Anatomic variations of the sphenoid sinus on computed tomography.

Anatomic variations of the vital structures adjacent to the sphenoid sinus can be jeopardized during functional endoscopic sinus surgery (FESS). The knowledge of the size and extent of pneumatization of the sphenoid sinus (SS) is an important condition for adequate surgical treatment of its disease. The bony anatomic variations of SS as well as its relationship with adjacent vital structures were reviewed in this paper. The study was performed on 267 patients with a complaint of chronic or recurrent sinusitis. Computed tomographic (CT) scans were obtained upon completion of therapy. The evaluations of the sphenoid sinuses were regarded separately, so as 534 sides were examined. Especially bony anatomic variations as well as mucosal abnormalities of the sphenoid sinuses were examined. Pneumatization of the pterygoid process and anterior clinoid process were found in 39.7% and 17.2% of the patients respectively. Vidian canal protrusion was found in a total of 158 sides of which 60 were bilateral. These entities were encountered usually when pneumatization of the pterygoid process occurred. Carotid canal and optic canal protrusions were found in 5.2% and 4.1% of the patients respectively. Mucosal thickening, and polyps or cysts of sphenoid sinuses were detected in 20.6% and 4.5% of the patients respectively. There was a statistically significant correlation between pterygoid pneumatization and vidian canal protrusion (p < 0.001), and vs. foramen rotundum protusion (p = 0.004). While the optic canal protrusion was found significantly associated with the anterior clinoid pneumatization (p < 0.001), there was no statistically significant correlation between a carotid canal protrusion and anterior clinoid pneumatization (p = 0.250). Sphenoid sinus surgery is very risky, because of changing variations of the cavity. We are in the opinion that detailed data from CT scans of SS will enable the surgeon to interpret any anatomic variations and pathological conditions before initiation of the surgical therapy.

Adolescent↗

PubMed2006

Piriformis syndrome resulting from a rare anatomic variation.

STUDY DESIGN: Case report. OBJECTIVES: We report a rare case of piriformis syndrome accompanying anatomic variation in the piriformis muscle and sciatic nerve. SUMMARY OF BACKGROUND DATA: Beaton classified anatomic variation in the piriformis muscle and sciatic nerve into 6 types based on cadaver studies. There has been no report in the English literature of surgical treatment for a case of piriformis syndrome accompanying Beaton type d anatomic variation. METHODS: A patient with sciatica showing no nerve root compression in lumbar MRI underwent pelvic MRI and perineurography of the sciatic nerve followed by CT. The findings in these images suggested piriformis syndrome accompanying anatomic variation of the piriformis muscle and sciatic nerve. Surgical treatment was performed. RESULTS: Surgical exploration of the piriformis muscle revealed Beaton type d anatomic variation. Both anterior and posterior lobes of the piriformis muscle were resected. The pain in the leg had completely disappeared after surgery. CONCLUSIONS: This is a very rare case of surgically treated piriformis syndrome resulting from type d anatomic variation in Beaton's classification. Pelvic MRI and perineurography of the sciatic nerve were useful for diagnosis in this case.

Buttocks↗

PubMed2005

Uncommon anatomic variations in patients with chronic paranasal sinusitis.

OBJECTIVE: Some uncommon anatomic variations would be encountered with the increasing number of patients with chronic paranasal sinusitis who have undergone functional endoscopic sinus surgery. The correct identification and proper treatment for these variations are important. STUDY DESIGN AND SETTING: A retrospective study of serial computed tomography scan images was conducted in 100 patients collected randomly. Uncommon anatomic variations were recorded and clinical features were analyzed. RESULTS: Five (5%) cases with uncommon anatomic variations were found. These variations included bilateral pneumatization of uncinate process (1%), large uncinate process mimics the middle turbinate (1%), nontraumatic protrusion of orbital contents through dehiscence of lamina papyracea (1%), and nasal septal pneumatization (2%). Two of these 5 cases caused some modifications of routine functional endoscopic sinus surgery procedures and another 2 variants commanded further caution during routine uncinectomy. CONCLUSION AND SIGNIFICANCE: Uncommon anatomic variations, though unusual, are not rare in chronic paranasal sinusitis patients. Procedures should be tailored for most of these special conditions.

Adolescent↗

PubMedDate not supplied

The facial canal: normal anatomy, variations and anomalies. II. Anatomical variations and anomalies involving the facial canal.

Explore the source record for details and available documents.

Chorda Tympani Nerve↗

PubMed2002

Anatomic variations of the paranasal sinus area in pediatric patients with chronic sinusitis.

Endoscopic endonasal surgery has been performed in children. Therefore, we need to know the precise anatomy and anatomic variations of the lateral nasal wall. This is important in order to achieve better surgical results and avoid complications. We also need to know the relationship between the anatomic variations and sinonasal disease. For the purpose of this study we assessed the anatomic variations of the lateral nasal wall and the association of these variations with chronic sinusitis in children. Forty-seven children with chronic sinus disease were included in the study. There were 25 female and 22 male patients with ages ranging from 2 to 16 years (mean 10.5+/-3.8 years). On coronal and axial computed tomographic (CT) scans, the anatomic variations of the lateral nasal wall and sinusitis were assessed. A pneumatized middle concha (MC) was the most common anatomic variation, followed by pneumatization of the superior concha (SC), Haller cell and agger nasi cell. Secondary MC, large ethmoidal bulla, maxillary sinus hypoplasia, Onodi cell, and uncinate process pneumatization were relatively rare. Maxillary sinusitis was the most common sinus infection, followed by ethmoidal, sphenoidal and frontal sinusitis in that order. There was no significant relationship between the sinusitis and anatomic variations except for some minor associations. In conclusion, anatomic variations in the lateral nasal wall are common in children. Local, systemic or environmental factors appear to be more important in pediatric sinusitis than the anatomic variations. Due to the absence of a definitive relationship between the anatomic variations and sinus disease, aggressive surgical interventions should be avoided while performing endonasal endoscopic surgery in the children.

Adolescent↗

PubMed1980

Anatomic variations in the first ray: Part I. Anatomic aspects related to bunion surgery.

Dissection and roentgenographic findings in 35 nonoperative cadaveric and freshly amputated feet were correlated with disorders of the first day--specifically the sesamoids. There are four noteworthy factors associated with first ray pathology. The most significant are axial rotation of the first metatarsal bone and degenerative changes at the first metatarsophalangeal joint. Significant anatomic variations can be correlated with failed bunion surgery.

Adolescent↗

PubMed2001

Anatomic variations and carpal tunnel syndrome: 10-year clinical experience.

The surgical findings in 147 consecutive hands that underwent primary carpal tunnel release between 1983 and 1993 were reviewed for anatomic variation. A classification is introduced for the two major types of variations found. The variations found within the carpal tunnel, termed intrinsic or Type I, were space-occupying lesions of muscular, bony, or varied soft tissue origin. The variations overlying the transverse carpal ligament, termed extrinsic or Type II, were nearly all muscular in origin. Seventy-four variations were found in 60 hands. Overall, an underlying variation was found in 41% of the hands. After applying a logistic model, it was found that patient age and hand dominance were important factors in predicting the presence of an anatomic variation. For patients 40 years of age or younger, the odds of observing an anatomic variation were 3.2 times higher than the odds of observing a variation in patients older than 40 years. The odds of observing an anatomic variation in the dominant hand were 2.3 times higher when compared with the odds of observing a variation in the nondominant hand. In patients 40 years of age or younger, with dominant side involvement, an anatomic variation was found in 71% of hands. In patients older than 40 years with nondominant side involvement, an anatomic variation was found in 24% of hands. Taking into account not only anatomic variations but also underlying medical disease and local injury, at least one was identified in 86% of hands.

Carpal Tunnel Syndrome↗

PubMed1993

[Computerized tomography in the evaluation of anatomic variations of the ostiomeatal complex].

This work was aimed at showing the main anatomical variations in the ostiomeatal complex which are usually depicted by CT. A hundred and thirty CT exams including 59 normal cases (45.4%) and 71 cases of chronic sinus disease (54.6%) were reviewed. The following anatomical variations were considered: concha bullosa, middle turbinate, septum, uncinate process and bulla changes, Haller cells and agger nasi cells. Anatomical variations were demonstrated in 69 patients--31 normal subjects and 38 patients with chronic sinusitis. The incidence of every anatomical variation was investigated and the results were compared with literature data. Excluding agger nasi cells, which were seen in nearly all patients, the most common variations were concha bullosa and septal spur and deviations, while the least common variations were those in the middle turbinate and uncinate process.

Chronic Disease↗

PubMed1997

The role of the ostiomeatal unit anatomic variations in inflammatory disease of the maxillary sinuses.

OBJECTIVE: The purpose of the study was to determine the correlation between bony anatomic variations of the ostiomeatal unit (OMU) and chronic maxillary sinusitis. The study was based on the hypothesis that the mucosal contact caused by the variations represents the critical factor in increasing the risk of maxillary sinusitis. MATERIALS AND METHODS: Thin section high resolution computerised tomography (CT) examinations of the paranasal sinuses in 73 consecutive patients with 113 anatomic variations of the OMU were retrospectively reviewed. The following CT features were assessed: (1) Type of anatomic variations, (2) presence of a mucosal contact in the OMU and (3) presence of maxillary disease. Statistical evaluation was carried out using chi 2-test. RESULTS: The following bony anatomic variations were found: Concha bullosa (67 cases), abnormalities of the uncinate process (18 cases), Haller's cells (24 cases) and large ethmoidal bulla (four cases). Only 52 of the 113 anatomic variations were associated with ipsilateral maxillary disease (mucosal thickening, mucous retention cysts, polyps, retained secretions). Of 113 variations, 44 caused a mucosal contact, 35 of these were associated with maxillary abnormalities, while in nine cases there were no pathologic changes. Of 69 variations, 17 did not cause mucosal contact (P < 0.05). CONCLUSION: Our data shows that, in the presence of anatomic bony variations, a contact between the mucosal surface of the OMU is valuable in predicting the likelihood of a maxillary inflammatory disease.

Adolescent↗

PubMed1991

Paranasal sinus bony anatomic variations and mucosal abnormalities: CT analysis for endoscopic sinus surgery.

Coronal plane computerized tomographic (CT) scanning has dramatically improved the imaging of paranasal sinus anatomy as compared to sinus radiographs. Increasingly, subtle bony anatomic variations and mucosal abnormalities of this region are being detected. Data regarding the "background" prevalence of these findings are needed to determine their clinical relevance. A detailed analysis of coronal plane CT scans of the paranasal sinuses obtained in 202 consecutively imaged patients was conducted. Special attention was directed toward identifying bony anatomic variations and mucosal abnormalities. Anatomic variations studied included pneumatization of the middle turbinate, paradoxical curvature of the middle turbinate, Haller's cells, and pneumatization of the uncinate process. Such bony anatomic variations were detected in 131 (64.9%) of 202 patients and were found with a similar frequency in patients scanned for sinus complaints and in those scanned for nonsinus reasons. Mucosal abnormalities were detected in 168 (83.2%) of 202 patients. For those patients scanned during the evaluation of sinus-like complaints, mucosal abnormalities were noted in 153 (92.2%) of 166 cases, and were predominantly detected in the anterior ethmoid region. For patients scanned during nonsinus evaluations, mucosal abnormalities were detected in 15 (41.7%) of 36 cases, without predilection for the anterior ethmoid region. Discussion regarding the prevalence and clinical significance of paranasal sinus bony anatomic variations and mucosal abnormalities is included as a guide to assist the otolaryngologist and/or radiologist in the evaluation of coronal sinus CT scans.

Adult↗

PubMed1997

The anatomical variations of sylvian veins and cisterns.

The anatomical variations of sylvian vein and cistern were investigated during the pterional approach in 750 operative cases with different pathologies. All patients were operated on at the Neurosurgical Department of Ataturk University Medical School, Erzurum, Turkiye. The patients underwent surgery for the lesions necessitating the right or left pterional approach. The findings were recorded during surgical intervention and observed through the operative sketches of the pathologies, the slides, and videotapes of the operations. In our study, we surgically classified the variations of sylvian vein, according to its branching and draining patterns. Type I: The fronto-orbital (frontosylvian), fronto-parietal (parietosylvian) and anterior temporal (temporosylvian) veins drain into one sylvian vein. Type II: Two superficial sylvian veins with separated basal vein draining into the sphenoparietal and Rosenthal's basal vein. Type III: Two superficial sylvian veins draining into the sphenoparietal and the superior petrosal veins. Type IV: Hypoplastic superficial sylvian vein and the deep one. Four types of sylvian vein variations were defined as follows. The type I was seen in 52.8% (n = 396), the type II was found in 19.2% (n = 144), type III was recorded in 18.2% (n = 137), and type IV, or hypoplastic and deep form was discovered in 9.8% (n = 73) of patients. The coursing of sylvian vein was in the temporal side (Temporal Coursing) in 62.4 percent of the cases (n = 469), in the frontal side (Frontal Coursing) in 25 % of the patients (n = 187) and in 9 percent of the cases (n = 67) in the deep localization (Deep Coursing). Only 3.6% of the cases (n = 27) showed Mixed Coursing. The variations of the sylvian cisterns were classified into three types, according to the relationships between the lateral fronto-orbital gyrus and the superior temporal gyrus. In Sylvian type, the frontal and temporal lobes are loosely (Sylvian Type A, wide and large) or tightly (Sylvian Type B, close and narrow) approximated on the surface thereby covering the substance of the sylvian cistern. In Frontal Type, the proximal part of the lateral fronto-orbital gyrus herniated into the temporal lobe. In Temporal Type, the proximal part of the superior temporal gyrus herniated into the lateral fronto-orbital gyrus. The variations of the sylvian cisterns in 750 patients with different pathologies, were as follows: in 47.7% (n = 358) Sylvian type A, in 27.2% percent (n = 204) Sylvian type B, in 16.3% (n = 122) frontal type and in 8.8% (n = 66) temporal type. We concluded that venous perfusion discorder of the brain is the most important factor during the pterional approach. Careful intraoperative assessment and protection of the sylvian vein, which is a surgical pitfall, is an indispensable part of the operation. The recognition of the anatomical variations of the sylvian vein and cistern, and the detailed knowledge of the microvascular relationships and the importance of preservation of this vein at that level, will allow the neurosurgeon, believing in the minimally invasive neurosurgical techniques, to construct a better and safer microdissection plan, to save time, and can prevent postoperative neurological deficits.

Adolescent↗