Radio-anatomical Study Research Articles

Psoas Muscle Morphology: A Novel Classification System and Its Anatomic Relationship with Adjacent Neurovascular Structures.

Cross-sectional radioanatomic study. To introduce a classification system using MRI to describe psoas morphology and examine the position of nearby neurovascular structures. Oblique lumbar interbody fusion (OLIF) and lateral lumbar interbody fusion (LLIF) offer sagittal malignment correction and reduced morbidity. LLIF has a higher incidence of nerve injuries, while OLIF has a higher incidence of vascular injuries. Measurements were completed on the left psoas at the inferior L4 endplate. Class A was designated if the ventral border of the psoas muscle was >2mm anterior; B if it was ≤ 2mm anterior or posterior to the vertebral body, and C if >2mm posterior to the vertebral body ventral border. Modified oblique corridor, measured as the distance between two lines, one at the medial border of the psoas muscle and the other at the lateral border of the nearest vascular structure, and a preferred LLIF trajectory was projected onto an axial image of the left psoas. If the trajectory violated the posterior third of the psoas, it was considered a dangerous approach due to potential iatrogenic nerve injury. 100 patient MRIs (Class A: 44; Class B: 27; Class C: 29) were analyzed. Average modified oblique corridor was 7.49mm. Modified oblique corridor varied amongst the three types of psoas morphologies (A: 8.99mm vs. B: 8.10mm vs. C: 4.66mm, P=0.040). LLIF trajectory intersected the 'danger zone' in 34.1%, 3.7%, and 0.0% of patients, (P<0.001) respectively. Class A psoas had the largest modified oblique corridor but highest proportion of those with a dangerous LLIF trajectory. Class C psoas had the narrowest modified oblique corridor, but no dangerous LLIF trajectories were identified.

A radio-anatomical study of median arcuate ligament syndrome: unveiling the morphology and morphometry of median arcuate ligament, celiac trunk, and superior mesenteric artery.

In the context of medical literature, a significant lacuna exists in understanding median arcuate ligament syndrome (MALS). While clinical aspects are well documented, literature lacks a robust exploration of the anatomical relationship between the celiac trunk and the median arcuate ligament (MAL). Morphometric parameters, including the vertebral level of MAL origin, MAL thickness, celiac trunk (CeT) origin level, diameter, and distances between CeT/Superior Mesenteric Artery (SMA) and the MAL center were observed on 250 CT angiograms. Cadavers (n = 11) were dissected to examine the same parameters and histo-morphological examination of MAL tissue was done. Radiological findings established average MAL thickness of 7.79 ± 2.58mm. The celiac trunk typically originated at T12. The average distance between the celiac trunk and the MAL center was 1.32 ± 2.04mm. The angle of the celiac trunk to the abdominal aorta was primarily obtuse. The average celiac trunk diameter was 5.53 ± 1.33mm. Histological examinations revealed a diverse MAL composition, indicating variable mechanical properties. This study provides comprehensive morphometric data on the anatomical relationship between the MAL and the celiac trunk. In contrast to available literature which says the average MAL thickness of > 4mm is an indicator of increased thickness, we observed much higher average thickness in the studied population. The findings contribute to a better understanding of normal anatomical variations which can serve as reference values for accurate radiological diagnosis of MALS. The histological examination revealed the heterogeneous nature of the MAL tissue composition, suggesting variable mechanical properties and functions in different regions.

Anatomical variations of interest for posterior nasal nerve cryotherapy in the treatment of chronic rhinitis: A radioanatomic study.

An unfavorable insertion of the middle turbinate for cryotherapy was present in 74.2% of cases. Placing cryoprobe 15-30mm above the nasal floor targets the nerves in 95.8% of cases. Centering the cryoprobe 38mm behind the inferior turbinate axilla targets the nerves in 94.6% of cases.

Evaluation of Feasibility of Medial Plantar Artery Flap With Computed Tomography Angiography in Diabetic Patients: A Pilot Radioanatomic Study.

Background A soft tissue defect resulting from a diabetic heel ulcer can be difficult to address due to limited reconstructive options and unique local area demand. The medial plantar artery flap is ideal for heel defect coverage as it provides a thick glabrous skin with good sensory feedback. The prerequisite of medial plantar artery flap surgery is a patent medial plantar artery, which is a branch of the posterior tibial artery (PTA). Nevertheless, no feasibility study of the medial plantar artery flap in diabetic patients with vascular insufficiency has been reported so far. We conducted a pilot study with the aim of investigating the patency of the medial plantar artery in diabetic patients with suspected peripheral artery disease to determine the vascular feasibility of the medial plantar artery flap in these patients. Material and methods A pilot study was performed at Sultan Ahmad Shah Medical Centre at International Islamic University Malaysia (IIUM). A total of 15 diabetic patients with suspected vascular insufficiencywho had undergone lower limb computed tomography angiography (CTA) from January 2022 to June 2023 were included in this study. All patients were identified via the electronic record system.Lower limb CTA images were retrieved from the Radiology Information System (RIS) and Picture Archiving and Communication System (PACS) and were double-reviewed.Both the posterior tibial artery (PTA) and medial plantar artery (MPA) were assessed for their patency, and the diameter of the lumens was measured if they were patent. Bedside clinical assessments such as palpation of pulses and portable Doppler assessment were evaluated to determine whether they could serve as substitutes for computed tomography angiography (CTA) in assessing the feasibility of medial plantar artery flap using the McNemar test. Results In this study cohort, the medial plantar artery was present in 16 legs and absent in another 14 legs. The largest diameter of the medial plantar artery was 2.5mm (range 0-2.5mm). Palpation of the posterior tibial artery was not optimal for predicting the patency of the medial plantar artery, with a false positive of 21.4% and a false negative of 68.7%. Similarly, a hand-held Doppler assessment of the posterior tibial artery was also ineffective, with a false positive of 64.3% and a false negative of 18.8%. While the medial plantar artery is a continuation of the posterior tibial artery (PTA), PTA patency did not necessarily correlate with medial plantar artery patency. This was demonstrated on CTA assessment, where two legs with absent PTA still have reconstitution, resulting in patency of the medial plantar artery. Additionally, one leg with patent PTA did not have a patent medial plantar artery distally due to calcified vessels. Conclusion This is a first-of-its-kind pilot study attempting to determine the feasibility of medial plantar artery in diabetic patients with vascular insufficiency. The medial plantar artery was present in more than 50% of the investigated lower limbs, paving the way for using the medial plantar artery flap in these patients. Nevertheless, a computed tomography angiogram is essential to determine the patency of the medial plantar artery prior to the flap procedure, as palpation and hand-held Doppler were inadequate to predict the patency of the medial plantar artery in these high-risk patients.

Morphometry of the Middle Cerebral Arteries: A Radio-Anatomical Study Based on Computed Tomography Angiography Findings

Morphometry of the Middle Cerebral Arteries: A Radio-Anatomical Study Based on Computed Tomography Angiography Findings

Retracted: Radioanatomical Study of the Skull Base and Septum in Chinese: Implications for Using the HBF for Endoscopic Skull Base Reconstruction.

[This retracts the article DOI: 10.1155/2022/9940239.].

Radioanatomical study of occlusive lesions of the superior mesenteric artery in atherothrombotic mesenteric ischemia

Radioanatomical study of occlusive lesions of the superior mesenteric artery in atherothrombotic mesenteric ischemia

Corpus callosum area and sectioning: a radioanatomical study correlated with MRI and cadaver morphometry.

The corpus callosum (CC) is the primary interhemispheric connection between the two cerebral hemispheres. Besides their similar morphological characters, there are differences in their measurements. This study aimed to divide the CC into groups using planes based on the anterior commissure (AC) and posterior commissure (PC) and to detect differences in CC magnetic resonance imaging (MRI) and cadaver samples between these groups. The study included 80 patients (40 male and 40 female patients) who underwent normal MRI in the midsagittal plane, and 38 cerebral hemispheres from 40 adult cadaver brains, with each hemisected in the midsagittal plane. The medial surface of the CC was divided vertically into three parts (the anterior, middle, and posterior zones) according to the AC and PC. Areas and parameters were measured in both the cadaveric hemispheres and patient MRI images. The total CC area and CC areas between, anterior, and posterior to the AC-PC vertical lines were the same in both the MRI and cadaver samples. In addition, morphometric measurements like the CC length, AC-PC length, and CC height at the AC and PC vertical lines, and their correlations were also found to be similar between the MRI and cadaver samples. This study proposes three areas according to AC and PC classification (anterior, middle, and posterior). This new proposed classification is suitable for stereotactic interventions and is useful for obtaining data from MRI images. However, it should be kept in mind that there may be changes and variations.

Purely nasal floor mucosa-free graft for reconstruction after endoscopic endonasal transellar approach: an anatomical and clinical analysis

Background/objective In this radioanatomical study with clinical correlate, we study a variation of the ‘extended nasal floor mucosa’ (ENFM) free-graft, the purely nasal floor mucosa (PuNFM) free-graft. The objectives of this study are to evaluate the coverage surface area provided by the PuNFM, study the adequacy of the PuNFM in the reconstruction of endoscopic endonasal approach (EEA) transsellar postoperative defects and compare and evaluate this reconstructive technique with current sellar region reconstruction practices. Methods Dissections were performed on five cadaveric specimens. PuNFM were harvested bilaterally and the area provided for reconstruction was calculated. Twenty-five consecutive cases of pituitary adenomas resected through an EEA were analyzed to estimate the sellar defect surface area (SDSA) after a transsellar EEA and calculate the area of PuNFM bilaterally. Results The median cadaveric SDSA was 4.77 cm2, with a median left and right side PuNFM area of 5.09 and 5.19 cm2, respectively. Clinically, the median SDSA was 5.36 cm2, and the total radiological PuNFM surface area was 5.46 cm2, with modified Knosp grade >2 tumors having larger SDSA than that of Knosp grade <2 tumors. The PuNFM graft proved to be most effective for covering modified Knosp <2 tumor defects. Conclusions The PuNFM represents a variation of the ENFM free-graft sellar defect reconstruction technique that provides sufficient surface area to reconstruct the majority of the sellar defects related to transsellar EAA for pituitary adenomas. This technique may positively impact sinonasal function and quality of life. Future prospective clinical studies are needed to verify these findings.

Anterior Column Realignment Using an Anterior-To-Psoas Approach: A Radiographic-Anatomic Feasibility Study at L1-L5.

Cross-sectional radioanatomic study. To determine the feasibility of performing an anterior column realignment (ACR) using an anterior-to-psoas (ATP) approach at L1-L5. Axial magnetic resonance images (MRI) of the L1-L5 disc levels obtained at a single institution were obtained and analyzed. The feasibility of performing an ACR was assessed using a combination of the size of the left oblique corridor (OC), the psoas morphology using the modified Moro classification, and the anterior disc edge to great vessel distance. Three hundred MRI studies obtained from 300 patients were included. All patients had a measurable left OC at the L1-L4 levels. Twenty patients (6.7%) had no measurable OC at the L4-L5 level. According to the modified Moro's classification, a high-rising psoas was seen in 4 patients (1.3%) at the L3-L4 level and 57 patients (19.0%) at the L4-L5 level. An ALL release was considered high risk due to no measurable space between the anterior disc edge and the great vessels in 54 patients (18.0%) at the L1-L2 level, 39 patients (13.0%) at the L2-L3 level, 119 patients (39.7%) at the L3-L4 level, and 226 patients (75.3%) at the L4-L5 level. ACR using an ATP approach is the most radioanatomically feasible at L2-L3. The L4-L5 level has the highest risk with regards to both the ATP approach and the ALL release for an ACR due to high rates of unmeasurable left OC and space between the anterior disc edge and the great vessels.

A radioanatomical study of 3rd segment terminal branches of the maxillary artery in the pterygopalatine fossa

This study describes the clinical anatomical topography and relationship of the terminal branches of the maxillary artery to the bony wall of the maxillary sinus in the pterygopalatine fossa (PPF) to estimate the bleeding risk during surgical interventions. Using contrasted computer tomography records, (i) the route of the maxillary artery in the infratemporal fossa, (ii) the number of the arteries in the critical PPF surgery plane, (iii) the diameter of the largest artery in the area and (iv) its relation to the posterior wall of the maxillary sinus were examined. Furthermore, measurements were extended with (v) the minerality of the bony posterior wall of the maxillary sinus on bone-window images. For statistical analyses Student’s t- and Fisher-test were applied. 50 patients (n = 50, 100 cases including both sides) were examined in this study. The maxillary artery reached the pterygomaxillary fissure on the lateral side of the lateral pterygoid muscle in 56% of the cases (n = 32), in 37% (n = 23) on its medial side and in 7% (n = 4) on both sides. The number of arteries at the level of the Vidian canal in the PPF varied between 1 and 4 with a median of 2. The diameter of the biggest branch was 1.2–4.7 mm, the median diameter was 1.90 mm. In 41% (n = 30) of the cases the biggest artery directly contacted the posterior wall of the maxillary sinus, and the mineral density of the posterior wall was decreased in 14.3% (n = 12) of all investigated cases. The present description and statistical analysis of the vasculature of the PPF optimizes operative planning—like clip size or the type and direction of the surgical approach—in this hidden and deep head/neck region.

Investigation of Pulmonary Artery and Ascending Aorta Morphology in the Coronavirus Disease 2019: A Radioanatomical Study.

This study aimed to determine the maximum diameters of the pulmonary artery and ascending aorta and their ratio to each other to enable early diagnosis and treatment of possible pulmonary hypertension and to prevent possible complications in patients infected with severe acute respiratory syndrome coronavirus 2. A total of 120 patients aged 40 years and older, 60 patients (30 females and 30 males) with severe acute respiratory syndrome coronavirus 2 infection and 60 individuals (30 females and 30 males), were included in this retrospective study. Maximum pulmonary artery and maximum ascending aorta diameters were measured at the level of bifurcatio trunci pulmonalis in the transverse axial plane by computed tomography, and their ratios to each other were determined. Our study revealed a statistically significant increase in maximum pulmonary artery and maximum ascending aorta diameters in both genders in patients with coronavirus disease 2019 compared to the control group and a statistically significant increase was found in the maximum pulmonary artery-maximum ascending aorta ratio in women with coronavirus disease 2019 compared to the control group (P < .05). Knowing the diameters of maximum pulmonary artery and maximum ascending aorta and the maximum pulmonary artery-maximum ascending aorta ratio in hospitalized severe acute respiratory syndrome coronavirus 2-infected patients is a valuable predictive marker of pulmonary hypertension and a guide in determining the appropriate treatment. These data, which are easy to calculate from thorax computed tomography, may be beneficial in the prognosis of the disease.

Investigation of Pulmonary Artery and Ascending Aorta Morphology in the Coronavirus Disease 2019: A Radioanatomical Study.

This study aimed to determine the maximum diameters of the pulmonary artery and ascending aorta and their ratio to each other to enable early diagnosis and treatment of possible pulmonary hypertension and to prevent possible complications in patients infected with severe acute respiratory syndrome coronavirus 2. A total of 120 patients aged 40 years and older, 60 patients (30 females and 30 males) with severe acute respiratory syndrome coronavirus 2 infection and 60 individuals (30 females and 30 males), were included in this retrospective study. Maximum pulmonary artery and maximum ascending aorta diameters were measured at the level of bifurcatio trunci pulmonalis in the transverse axial plane by computed tomography, and their ratios to each other were determined. Our study revealed a statistically significant increase in maximum pulmonary artery and maximum ascending aorta diameters in both genders in patients with coronavirus disease 2019 compared to the control group and a statistically significant increase was found in the maximum pulmonary artery-maximum ascending aorta ratio in women with coronavirus disease 2019 compared to the control group (P < .05). Knowing the diameters of maximum pulmonary artery and maximum ascending aorta and the maximum pulmonary artery-maximum ascending aorta ratio in hospitalized severe acute respiratory syndrome coronavirus 2-infected patients is a valuable predictive marker of pulmonary hypertension and a guide in determining the appropriate treatment. These data, which are easy to calculate from thorax computed tomography, may be beneficial in the prognosis of the disease.

Parameters for estimating the feasibility of implantation of a semi-implantable bone conduction device (SIBCD) in children and adolescents

PurposeIn children and adolescents, preoperative planning for a semi-implantable bone conduction device (SIBCD) is crucial. The geometric changes of the new version of a common SIBCD should enable a higher rate of successful implantation due to its flatter actuator. Thus, this radioanatomic study compared the rate of successful implantation of both device versions at the traditional mastoidal localization and two alternative sites, retrosigmoidal, and parietal, and investigated parameters helping to estimate the feasibility.MethodsA retrospective analysis of 136 CT scans of 0 to 20-year-old patients, evaluation of demographic parameters, radioanatomy, and assessment of head diameter was conducted. The feasibility was investigated for certain age groups at three implantation sites. Prediction of feasible implantation by means of different parameters was calculated.ResultsA significant higher implantation rate was observed with the new device for all three sites and age groups. The age group of 6–8 years (n = 19) had most striking differences with a 58.1% rate of successful implantation with the new device without spacer (80% with spacer) at the mastoidal localization, whereas none with the old implant. Head diameter was identified as the most predictive parameter regarding all implantation sites (mastoidal: p = 0.030; retrosigmoidal: p = 0.006; parietal: p < 0.0001), age for the mastoidal (p < 0.0001) and retrosigmoidal (p < 0.0001), and gender for the parietal site (p = 0.001).ConclusionThe geometric changes of the actuator lead to a higher rate of successful implantation in all age-groups and all three localizations with reducing the requirement for spacers. Parameters age and head diameter might aid in estimating the rate of successful implantation in young patients and may be a novel tool to assist in the decision-making process for a SIBCD.

Radioanatomical Study of the Skull Base and Septum in Chinese: Implications for Using the HBF for Endoscopic Skull Base Reconstruction.

Objective Radioanatomy provides surgeons with different choices to prevent the failure of reconstruction caused by improper flap selection and the occurrence of CSF leakage or other severe complications. To establish a radioanatomical model, this study radioanatomically investigated the use of the Hadad–Bassagasteguy nasoseptal flap (HBF) in skull base reconstruction performed via the transethmoidal, transsphenoidal, and transclival approaches to provide preoperative guidance for the selection of approaches for skull base reconstruction and preparation of the HBF. Methods The computed tomography images of 40 Chinese adults were selected for the radioanatomical measurement of data related to the HBF and skull base reconstruction via the transethmoidal, transsphenoidal, and transclival approaches. The results were analyzed using radioanatomy combined with SPSS-based analysis. Results In the 40 patients, the area of the HBF exceeded that of skull base defects reconstructed via the transethmoidal approach by 10.21 ± 1.97 cm2, and the anterior margin width, posterior margin width, upper margin length, and lower margin lengths of the HBF all exceeded the corresponding values of skull base defects requiring reconstruction by at least 8.4 mm. The area of the HBF exceeded that of reconstructed skull base defects by an average of 10.72 ± 2.04 cm2. The area of the HBF exceeded that of skull base defects reconstructed via the transclival approach by 9.01 ± 2.87 cm2. The difference between the anterior margin width of the HBF and the middle width of skull base defects reconstructed via the transclival approach did not exceed 6 mm in only one case (5.4 mm). Conclusion In Chinese adults, the HBF can cover skull base defects reconstructed via the transethmoidal, transsphenoidal, and transclival approaches, permitting its use in skull base reconstruction performed via all three approaches. Radioanatomy can be used for preoperative guidance to plan surgery via the transethmoidal, transsphenoidal, and transclival approaches.

The trajectory characteristics and clinical significance of the left-sided lumbar segmental artery: a prospective cross-sectional radio-anatomical study.

Vascular injury to the lumbar segmental arteries is a devastating complication in minimally invasive lumbar interbody fusion. Previous studies on the anatomy of the lumbar segmental arteries are limited. This prospective cross-sectional study aims to quantitatively describe the brief trajectory of the lumbar segmental arteries on the left side (SegAL) and to discuss its clinical significance. One hundred and two asymptomatic volunteers were prospectively enrolled and underwent computed tomography angiography (CTA). Anatomical parameters including the existence rate, relative positions and directions of SegAL were measured. Mann-Whitney U tests were performed, and statistical significance was set at P<0.05. A total of 404 lumbar SegAL were identified. The SegAL of L1, L2 and L3 were identified in all subjects while the L4 SegAL were absent in 9 of 102 (8.8%) and the L5 SegAL were absent in 97 of 102 (95.1%) volunteers. In 25 of 97 (25.8%) volunteers without the L5 SegAL, the branches of the L4 SegAL ran along the disks. Meanwhile, the branches of L3 intersecting over the intervertebral discs (IVD) were found in 8 of 9 (88.9%) subjects without the L4 SegAL and in 4 of 93 (4.3%) subjects with L4 SegAL. The branch angles between the L1, L2 SegAL and the aorta were significantly acute (P<0.05). The L3 SegAL ran approximately vertically with the aorta while the branch angles of the L4 SegAL were significantly blunt (P<0.05). according to the distances measured, on the anterior vertebral walls, the SegAL of L1 and L2 were significantly closer to the inferior vertebral walls than the SegAL of L3 and L4, while on the posterior vertebral walls, the L3 and L4 SegAL were significantly closer to the inferior walls. Arterial branches may course over the L3-4 and L4-5 IVD spaces and the branches over the L3-4 disks are more likely to be present when L4 segmental arteries are absent, thus posing potential risks of arterial complications. Because of the SegAL adjacent to the disks, the risk of arterial injury may be higher anteriorly at L1 and L2 and higher posteriorly at L3 and L4.

Morphometric Examinations of Internal Carotid Arteries of Patients with Hypertension and Patients with Type 2 Diabetes Mellitus: A Radio Anatomic Study Based on Computed Tomography Angiography Findings.

The aim of this study is to examine the relationship between the morphological features of A.carotis interna (ICA) and symptoms affecting cerebral blood circulation including type 2 diabetes mellitus (T2DM) and hypertension (HT). In this study, retrospective morphometric analysis of ICA measurements from 100 patients (45-60 years old) was performed on Computed Tomographic Angiography (CTA) images. The images were divided into four groups: patients with HT (group 1), patients with T2DM (group 2), patients with HT and T2DM (group 3), and healthy control group (group 4). Length and diameter measurements of the cervical, petrous, cavernous and terminal segments of the ICA were made by using 3D CTA images and recorded. The measurements of the male and female patients were compared by Mann Whitney-U test and the the groups were compared by using Kruskall Wallis H test. It was found that, there were statistically significant differences between male and female patients in terms of right and left petrous, cavernous and terminal segments of the ICA in Group 1, right and left cervical left cavernous in Group 3, left cervical, right and left petrous, cavernous and right cavernous in Group 4 (p 0.05). According to the Kruskall Wallis H test analysis results, it was determined that there was no statistically significant difference between the patients in 4 groups for all segment measurements (p 0.05). As a result; It was determined that ICA was more affected by hypertension than diabetes. In addition, we think that being knowledgeable of morphometric measurements of ICA will guide the radio-anatomical evaluations and increase the level of microanatomical knowledge in surgical treatment.

Anterior Skull Base Analysis from Coronal and Reconstructed Computed Tomography: Radio-Anatomical Study

Endoscopic sinus and skull base Surgery has gained significant improvement widely all over the world. A computerized tomography (CT) scan provides a detailed anatomy of the skull base especially the bone framework. This study aims to analyze the fixed anatomical bony landmarks of the anterior skull base through coronal and reconstructed CT in the context of the Nepalese population and guide the surgeon to perform endoscopic sinus and skull base surgery safely. This Prospective study includes 70 Computerized Tomography scans of Paranasal sinuses. The different measurement from nasal floor to skull base was taken in coronal and reformatted sagittal CT scan. Mean, standard deviation, minimum and maximum values were analyzed using descriptive statistics. Student T-test was applied to compare between right and left side. This study includes 75 patients between 18 to 77 years. The measurement from nasal floor to the cribriform plate and ethmoidal roof in right and left side were, mean± SD (47± 4.1, 45.3±4.3, 47.9±5.1, and 49±8.5 mm) respectively. Mean Take off angle at the cribriform plate was 43.9 ±10.9°on right side and 43 ± 9.4° on the left side. The distance from the nasal spine to the skull base (mean ± SD) at nasofrontal recess, bulla ethmoidalis, and the junction of sphenoethmoid levels at right sides were 51.5 ± 4.7, 52.9 ± 4.1, and 61.2 ±4.7 little higher at left side. This study provides a detailed analysis of the anterior skull base in coronal and sagittal CT scans which helps to reduces complications.

Age-dependent differences of the depth of olfactory fossa in children

ObjectiveWith this radio-anatomical study, we aimed to describe the distribution of the depth of the olfactory fossa based on the Keros classification in the pediatric population in our region and to reduce complication rates by providing normative data. MethodsThis was a retrospective study conducted with computed tomography imaging of the paranasal sinuses of 390 pediatric patients referred over a six-year period in Sakarya and Kocaeli University Faculty of Medicine. Patients were divided into 3 groups as 1–6, 6–12, and 12–18 years old. The depth of the olfactory fossa was measured and classified according to the Keros classification. The incidence of Keros asymmetries was also investigated. ResultsThe distribution of the depth of a total of 780 olfactory fossa according to the Keros classification was 24.7% Keros I, 65.9% Keros II, and 9.4% Keros III. When the groups were evaluated with each other and within each group, it was seen that the prevalence of Keros I type was significantly higher in the first group (p<0.05), and the prevalence of Keros type II was significantly higher in the second and third groups (p<0.05). Apart from this, the number of Keros type III increased in the third group compared to the first two groups and showed a statistically significant difference (p<0.05). Among all patients, asymmetry of the olfactory fossa was detected in 29 patients (7.4%). Although the number of olfactory fossa asymmetry was low in group I, it was not significantly different between the groups (p>0.05). ConclusionIn our study, high Keros I rate and low Keros III rate in children aged 1–6 were remarkable. Especially for children under the age of six, questions arise about the validity of the Keros classification. More detailed studies in larger populations, in different ethnicities, and with various age groups are needed. Level of evidenceLevel 3.

Posterior auricular artery helix root free flap—part I: radio-anatomical study

Full-thickness defects of the distal nose are an ongoing surgical challenge. Among the available techniques, pre-auricular chondrocutaneous free flaps based on the superficial temporal artery (STA) have good aesthetic and functional outcomes. However they often require autologous venous grafts. The aim of this radio-anatomical study was to evaluate the feasibility of the helix root free flap based on the posterior auricular artery (PAA). Vascular lengths, diameters, and networks were investigated in flaps harvested from cadavers. The perfusion of the flaps was studied by injecting patent blue. Some flaps were also injected with contrast agent and studied by angiography and computed tomography. Ten flaps from seven fresh cadavers were dissected and analysed. The mean length of the PAA was 114.2 mm and the mean diameter was 2.2 mm. Perfusion was investigated in six flaps and considered good in three of these. The study results demonstrate the feasibility of PAA-based helix root free flaps. This alternative technique provides an 11 cm pedicle with vessels of appropriate calibre, facilitating any potential microsurgery. The scar is mostly hidden behind the ear. This PAA-based helix root free flap could be a reliable and promising single-stage procedure to repair complex defects of the alae nasi.