Topographic anatomy of the endolymphatic sac: a pilot cadaveric dissection study.

PURPOSE: The precise location of the endolymphatic sac (ES) may be difficult during surgical approaches. This morphometric study aimed to determine the exact location of ES in adult human cadavers for the management of pathologies such as Meniere's disease. METHODS: Twenty temporal bones of 10 adult cadavers (mean age: 70 ± 13.40 years, range: 45-92 years; sex: 4 males and 6 females) fixed with 10% formalin were bilaterally dissected to obtain numeric data about the location of ES. RESULTS: Distances of ES to the posterior semicircular canal (PSC), Donaldson line (DL), sigmoid sinus (SS) and sinodural angle (SA) were found as 2.76 ± 1.18 (0.96-5.58) mm, 1.74 ± 1.13 (0.58-5.07) mm, 2.30 ± 1.09 (0.54-4.91) mm and 16.04 ± 3.15 (9.82-22.18) mm, respectively. In addition, the angle between the tangents passing through the cortical bone (CB) and SS was determined as 35.37°±11.32° (21.30°-60.58°). No statistical difference was found between right-left or male-female measurements (p > 0.05). CONCLUSION: DL, SS, and PSC are essential anatomical landmarks for determining the location of ES. The spatial location of SS, including its depth to the cortical bone and the distance to anteriorly located anatomical structures of the mastoid cavity consisting of the facial nerve and PSC, is believed to be underlined for ES surgery. Our data may be used as a database to further define the relationship between ES and adjacent anatomical structures (SS, PSC, etc.) during the application of surgical approaches.

Cochleo-facial corridor to the vestibule and fundus of the internal auditory canal through oval window: a minimal invasive and cochlea sparing approach.

PURPOSE: This cadaveric work aimed to test the effectiveness of a modified surgical corridor (ExpTSA: expanded transcanal supracochlear approach) developed for anatomic cochlear preservation in selected vestibular schwannoma patients necessitating to perform cochlear implantation for appropriate cases to achieve the best outcome. METHODS: The ears of 10 cadavers (at mean age 75.70 ± 13.75 years, range 45-92 years) were dissected from the external auditory canal (EAC) to the internal auditory canal by ExpTSA under the guidance of a microscope and endoscope. All stages of the surgical process were recorded step by step and evaluated morphometrically. RESULTS: The vestibular base was successfully reached in all ears without damaging the cochlear morphology and facial nerve. The vestibular base was 23.33 ± 2.02 mm away from the entrance (external orifice) and 10.26 ± 1.33 mm from the exit (internal orifice) of EAC. The oval window and vestibular base were measured to be 2.94 ± 1.05 mm and 5.87 ± 1.24 mm deep from the facial nerve, respectively. The normal areas of the oval window, the exit and entrance of EAC were found as 2.90 ± 0.81 mm2, 42.52 ± 13.66 mm2, and 110.73 ± 25.32 mm2, respectively. After ExpTSA procedure, the areas of the oval window (11.04 ± 2.83 mm2), the exit (122.45 ± 20.41 mm2) and entrance (167.49 ± 30.94 mm2) of EAC were expanded approximately 280%, 188%, and 50%, respectively. CONCLUSION: The ExpTSA may be performed for accessing to the vestibule and fundus of IAC for tumor removal of intravestibular schwannoma patients (with or without fundus involvement) with unserviceable hearing, preserving the cochlear morphology.

Evaluation of Bell's palsy in the cerebellopontine angle: An MRI study.

BACKGROUND: Evaluation of cranial nerve morphology through measuring cross-sectional area (CSA) on magnetic resonance imaging (MRI) is increasing day-by-day in clinical diseases. In Bell's palsy (BP), the manifestation of the enlarged CSA of the facial nerve (FN) may be used for diagnosis. This study aims to evaluate whether there is an enlargement of the cisternal FN in BP. METHODS: This retrospective study included 43 patients diagnosed with BP. In the reconstructed MRI, the long (LD) and short (SD) diameters of the paralytic and normal sides of the FNs located in the cerebellopontine angle were measured, and the CSA was calculated using the Radinsky formula. Before the radiologic measurement, a preliminary experiment was carried out on the rat sciatic nerve to be able to determine the actual nerve boundary on MRI. FINDINGS: There was a statistically significant relationship between paralytic and normal sides in the measurements of LD, SD, and CSA. The paralytic side was larger than the normal side in the cisternal FN. According to the Receiver Operating Characteristic (ROC) curve, BP can be estimated with 60% sensitivity and 70% specificity by the CSA of the FN more than 1.04 mm2 . As a result of the preliminary experiment, it was found that the actual nerve boundary was at approximately 50% intensity between the minimum and maximum values. CONCLUSION: Although entrapment of FN in the labyrinthine segment in BP was known, this study showed that the cisternal FN, which could be evaluated more conveniently, enlarged in the paralytic side compared with the normal side, and revealed the necessity of performing the comparison amongst the MRI studies on BP patients by a standardised measurement method. This study will also help clinicians to make a decision in the diagnosis of BP by giving a cut-off value for the CSA.

Comparison of fetal and adult tympanic membrane sizes: a cadaveric study.

OBJECTIVE: The work aimed to compare fetal and adult tympanic membrane (TM) sizes for understanding dimensional development from intrauterine life to adulthood. METHODS: Fifty-six temporal bones (18 fetuses, 10 elderly adults, half male and half female in each group) were included in this study. Using a digital image software, the TM height, width and area were measured. RESULTS: The mean area, height and width of the TM in adults were found as 58.84 ± 22.01 mm2, 9.06 ± 1.33 mm, and 8.10 ± 1.43 mm, respectively. Moreover, the mean area, height and width of the TM in fetuses were measured as 47.62 ± 12.57 mm2, 8.22 ± 1.12 mm, and 7.25 ± 1.15 mm, respectively. The TM dimensions were increasing in fetuses between 20-32 weeks of gestation. However, the TM dimension was statistically similar at the 7th month, the 8th month and adult periods. The TM height was greater than its width in fetuses and adults. CONCLUSION: The calculated regression equations of the TM parameters in fetuses may be used to estimate its size. The TM size did not change from the 7th gestational month, and thus the membrane reached adult diameter in fetal life. The TM height and width showed a very wide range; therefore, we thought that the 12 mm (the height) × 10 mm (the width) graft might be ideal dimension during the repair of the TM perforations.

Anatomic features of the fetal round and oval windows, and their relations with the tympanic nerve.

OBJECTIVE: The study aimed to examine morphometric properties of the round window (RW) and oval window (OW) and to show their relation with the tympanic nerve (the Jacobson's nerve, JN) in human fetuses from the otologic surgeon's perspective. METHODS: Thirty temporal bones of 15 fetal cadavers (8 males, 7 females) aged with 24.40 ± 3.71 weeks were included in the study. The height, width and surface area of the RW and OW and also distance from the JN to the OW and RW were measured. RESULTS: The height, width and surface area of the RW in this work were measured as 1.48 ± 0.25 mm, 1.57 ± 0.37 mm, and 2.05 ± 0.69 mm2, respectively. The RW was detected as round-shaped (8 cases, 26.7%), oval-shaped (15 cases, 50%), and dome-shaped (7 cases, 23.3%). The height, width and surface area of the OW were measured as 1.42 ± 0.26 mm, 2.90 ± 0.44 mm, and 3.63 ± 0.74 mm2, respectively. The OW was observed as oval-shaped (15 cases, 50%), kidney-shaped (10 cases, 33.3%), D-shaped (4 cases, 13.3%), and trapezoid-shaped (1 case, 3.3%). The JN was found 1.21 ± 0.60 and 1.18 ± 0.54 mm away from the RW and OW, respectively. CONCLUSION: This study containing morphological data about the shapes, diameters and area of the RW and OW may be useful to predict surgical difficulty, and to select implants of suitable size preoperatively for the windows. Knowing the relationship between the JN and the windows can be helpful to avoid iatrogenic injuries of the nerve.

Anatomic features of the cranial aperture of the optic canal in children: a radiologic study.

OBJECTIVE: This study aimed to peruse anatomic features of the cranial aperture of the optic canal (CAOC) for obtaining an extended morphometric dataset in children. METHODS: Computed tomography images of 200 children were included in this retrospective work to analyze the shape, location and diameters of the CAOC. RESULTS: The CAOC area, width and height were observed as 17.53 ± 2.80 mm2, 6.12 ± 0.84 mm, and 4.35 ± 0.64 mm, respectively. The angle of the optic canal in axial plane was found as 39.28 ± 5.13°, while in sagittal plane as 16.01 ± 6.76°. The distance between the CAOC and the midsagittal line was 7.17 ± 1.48 mm. The CAOC was measured as 54.04 ± 5.23 mm and 42.55 ± 3.28 mm away from the anterior and lateral boundary of the anterior skull base, respectively. The CAOC shape was described as the tear-drop (186 foramina, 46.5%), triangular (156 foramina, 39%), oval (47 foramina, 11.8%), and round (11 foramina, 2.8%). CONCLUSION: The depth, angle and diameter measurements belonging to the CAOC were changing according to its shape or demographic data (e.g., sex and age). Therefore, preoperative radiologic evaluation containing the shape, location and size of the CAOC should be considered by multidisciplinary operating teams in terms of surgical interventions such as implant positioning.

Anatomy of the Anterior Clinoid Process in Human Fetuses.

PURPOSE: The main objective of this study was to display the morphologic properties of the anterior clinoid process (ACP) in human fetuses in term of early childhood surgeries. METHODS: Twenty-four (10 females and 14 males) fetal cadavers aged from 16th to 28th weeks of gestation (at mean, 21.54 ±â€Š3.11 weeks) were included in the present study. The dimensions of ACP were measured with a digital image analysis software. RESULTS: Taking into account the length, width, and angle of ACP, it was classified as Type 1 in 20.83% (10 cases), Type 2 in 10.42% (5 cases), Type 3 in 10.42% (5 cases), Type 4 in 2.08% (1 case), Type 5 in 8.33% (4 cases), Type 6 in 16.67% (8 cases), Type 7 in 8.33% (4 cases), and Type 8 in 22.92% (11 cases). According to the attachment site of the optic strut (OS) relative to ACP, OS was identified as the anterior 3/5 in 16.67% (8 cases), anterior 4/5 in 68.75% (33 cases), and posterior 1/5 in 14.58% (7 cases). Neither right-left nor male-female significant differences were observed between the quantitative values belonging to ACP and OS. CONCLUSION: The percentage of the most complex and challenging type of ACP (the long, narrow, and narrow-angled ACP) in fetuses was found to be close to adults. Thus, routine adult surgical procedures such as anterior clinoidectomy might be successfully used in young children and infants. The attachment site of OS relative to ACP in adults was more anterior according to fetuses probably due to postnatal development such as the pneumatization of the sphenoid bone. In this regard, for pediatric neurosurgeons to avoid iatrogenic injuries and to select appropriate surgical approaches, further studies conducted on the attachment of OS relative to ACP in children are needed.

Radiologic analysis of the location, shape and size of the external aperture of the carotid canal in children.

OBJECTIVES: This retrospective computed tomography (CT) study was aimed to assess the growth dynamic of the external aperture of the carotid canal (EACC) in children aged between 1 and 20 years. METHODS: Two hundred patients (sex 100 females/100 males, average age 10.50 ± 5.77 years) with good head CT image quality were included in this study. CT images of the patients were used to obtain data related to the location, shape and dimension of EACC. RESULTS: EACC shapes were identified as oval shaped, round shaped, and tear-drop shaped in 58.3% (233 sides), 24% (96 sides) and 17.8% (71 sides), respectively. EACC length, disEACC-MSP (distance between EACC and midsagittal plane), and EACC width did not change from the prepubescence period; while, the disEACC-SC (distance between EACC and supramastoid crest) seemed to reach adult size in the postpubescence period. Linear functions for EACC length and width were calculated as: y = 5.453 + 0.091 × years, and y = 5.398 + 0.059 × years, respectively. CONCLUSION: The regression equations of the measured parameters representing the growth dynamic of EACC in children can be helpful to estimate its size, location and angulation, which suggest that the dimension and distances to certain anatomical landmarks seemed to reach adult size in different developmental periods. In this context, the findings of this study may seem to emphasize the importance of preoperative radiological evaluation on skull base, related to EACC, for multidisciplinary surgeon teams during childhood surgeries in terms of patients' positioning, and the selection of appropriate surgical approach.

Growth dynamic of the geniculate ganglion in children: a retrospective computed tomography study.

PURPOSE: The main aim of this retrospective computed tomography (CT) study was to examine the morphometric development of the geniculate ganglion (GG) in children aged between 1 and 18 years for surgical approaches. METHODS: This study was placed on 41 patients (20 females and 21 males) including cochlear implantation cases aged from one to 18 (at mean, 6.44 ± 5.79) years. All the measurements belonging to the length, width and area of GG were performed with a CT scanner. RESULTS: The morphometric values of GG were not different in terms of sex or side, statistically (p > 0.05). The length (p = 0.155) of GG was not correlated with the increasing ages from one to 18 years; however, its area (p < 0.001) and width (p = 0.003) were found to be increased in the childhood period. Linear functions for the length, width and area of GG were calculated as y = 2.028 + 0.011 × age (years), y = 1.496 + 0.014 × age (years), and y = 3.239 + 0.035 × Age (years), respectively. The dehiscence of GG was found in 22 (26.8%) out of 82 temporal bones. CONCLUSION: Our data suggested that the area and width of GG were progressively increasing with age in the childhood period. The calculated formula representing the growth dynamic of GG in children and the incidence of the presence of the dehiscent GG can be useful for radiologists and otologists to estimate its size and to avoid iatrogenic injury during early childhood surgeries.

Early diagnosis of Grisel's syndrome in children with favorable outcome.

PURPOSE: The painful torticollis only itself may be a major sign for the diagnosis of Grisel's syndrome (GS). It is known as an inflammatory atlantoaxial rotatory subluxation following upper respiratory tract infections (URTI) and surgical otolaryngological procedures. PATIENTS AND METHODS: The analysis of 16 pediatric GS patients were reviewed retrospectively by considering the diagnosis, the treatment modality, and the prognosis at the Department of Neurosurgery and Otorhinolaryngology in Mersin University, Faculty of Medicine between 2008 and 2018. In addition to the clinical cases, five cadavers were used to demonstrate atlantoaxial region, particularly the ligamentous complex and articulation of the atlas-axis, for the mechanism of these rare entities. RESULTS: The most common etiological factor of GS was URTI with 81.25% among 16 patients. Painful torticollis was the primary symptom of pediatric patients at admission. The X-Ray, computerized tomography (CT), and magnetic resonance imaging (MRI) investigations were used for the definitive diagnosis in the first week of admission, except one. No morbidity, mortality, and deformity were reported in this series. CONCLUSIONS: Early diagnosis is the principle of GS for avoiding of permanent neck deformity and complex surgical procedures. If GS can be diagnosed without any doubt by only considering patient's history and clinical examination, CT scan is not recommended due to harmful effects of radiation. The treatment was achieved by reduction, external fixation under analgesia, or sedoanalgesia accompanying with antibiotic and anti-phylogistic treatment.

Evaluation of the Foramen Magnum Area Calculated by Different Methods: A Radioanatomic Study.

PURPOSE: The main objective of the study was to evaluate the probable diversity in the area of the foramen magnum (FM) calculated by different measuring methods. METHODS: The study was conducted on 24 dry skulls, present in the collection of the Anatomy Department, Faculty of Medicine, Mersin University. The area of FM was calculated by different measurement methods including automatic field setting, Teixeria and Radinsky formulas obtained from anatomic (ASM), photographic (PSM) and radiologic (RSM) skull measurements. RESULTS: The areas of FMs calculated by Teixeria formula in RSM, PSM, and ASM were as follows: 857.96 ±â€Š99.97 mm, 796.68 ±â€Š105.08 mm, and 820.86 ±â€Š96.40 mm, respectively. The areas calculated by Radinsky formula in RSM, PSM, and ASM were as follows: 851.37 ±â€Š99.68 mm, 792.63 ±â€Š104.18 mm, and 814.85 ±â€Š94.99 mm, respectively. Lastly, the areas calculated by the automatic field setting of RSM and PSM software were as follows: 799.75 ±â€Š103.38 mm and 752.83 ±â€Š105.60 mm, respectively. CONCLUSION: Statistical significance was observed between the areas of FM obtained from RSM, ASM, and PSM when calculated by the automatic field setting, Teixeria formula, and Radinsky formula. The authors think that considering the amorphous shape of FM, the automatic field setting of the software should be used to obtain the most accurate numerical data related to the area of FM.

Multiple muscular abnormalities in a fetal cadaver with CHARGE syndrome.

The CHARGE syndrome characterized by coloboma, heart defects, atresia of the choanae, retarded growth, genitourinary hypoplasia, and ear anomalies is one of the rare syndromes. Although certain clinical issues (scapular winging, sloping shoulder, Sprengel's deformity, kyphosis and scoliosis) which could be related to abnormalities in musculoskeletal structures of the neck and shoulder have been identified in CHARGE syndrome, data on details of muscle anomalies seem to be quite limited in the literature. In this case report, bilateral multiple muscular abnormalities (agenesis of the trapezius, presence of the rhombo-atloid muscle, and presence of the bipartite rhomboid minor with superficial and deep parts) was presented in a fetus cadaver with atypical CHARGE syndrome to attract the attention of clinicians for definitive diagnoses and surgical reconstruction of the shoulders deformity such as scapular winging and Sprengel's deformity. By considering the previous studies, we propose that the absence of the trapezius, as well as the other muscle abnormalities around the neck and shoulder, should be revised as being a component of CHARGE syndrome.

Evaluation of the stapedial tendon growth dynamic in human fetuses.

PURPOSE: The main objective of the study was to investigate the morphometric properties of the stapedial tendon (ST) for pediatric otosurgeons and anatomists. METHODS: The present study was placed on 15 fetuses (8 females, 7 males) aged from 20 to 30 weeks of gestation (at mean, 24.27 ± 3.24 weeks) using the collection of the Anatomy Department of Medicine Faculty, Mersin University. All measurements were obtained with a digital image analysis software. RESULTS: In terms of male/female or right/left comparisons, no statistically significant difference was found in relation with the numerical data of ST. The surface area, length, and width of ST were detected as follows: 0.61 ± 0.15 mm2, 1.27 ± 0.30 mm, and 0.45 ± 0.08 mm, respectively. The absence of ST was observed in two fetuses with and without severe malformations. In another fetus with cleft lip and polydactyly, multiple abnormalities were bilaterally identified in the middle ear: (1) the absence of the incudostapedial joint and (2) the presence of an abnormal tissue attaching to the stapes. The abnormal tissue was determined to be irregular dense connective tissue using light microscope and electron microscope. CONCLUSION: Our findings showed that ST did not proportionally grow according to increasing gestational weeks. In the light of the numerical data, we thought that similar to stapes, ST attains the adult size in the fetal period. As ST anomalies may accompany severe malformations (e.g., cleft lip, polydactyly or syndactyly) that can be easily detected on observation by clinicians, we suggest that the detailed examination of middle ear in newborns should be taken into account for early diagnosis of conductive hearing loss to prevent any management delays.

The Measurement of Various Anatomical Structures and Assessment of Morphometric Development of Fetal Skull Base.

BACKGROUND: As the skull base has a complex anatomy, we underline the importance of anomalies for side asymmetry. It is useful to investigate relationship between anatomical structures for the surgical procedure orientations. Dural adherence, enlarged superior petrosal sinus, influence of neural crest cells, and cranial base ossification are among the factors in morphometric growth on skull base. MATERIAL AND METHODS: Twenty-five fetuses of an estimated gestational age ranging from 17 to 34 weeks were studied in the Anatomy Laboratory of Mersin University Medical Faculty. Craniotomy was made to each fetus and brain hemispheres were dissected. We put plates, passing from the external points of lateral and anterior-posterior borders of fetus heads that are perpendicular to each other. An analytical calculation was formulated for the angle of foraminae to the root of zygoma by using different formulations depending on their posterior or anterior location to the root of zygoma. Statistical method was based on correlation analysis, simple regression, independent 2 group t tests, SPSS20.0, and MedCalc 11.5 (MedicReS, New York, NY). RESULTS: Neither side dominance for the jugular foramen, nor the differences of foramen rotundum, spinosum, and ovale to anterior skull wall, root of zygoma, and to midline were found to be significant. CONCLUSION: There is a debate on asymmetry of foramina of the skull base. No certain consensus about the initiation time and the causes of asymmetry in the past was documented. Studies are to be encouraged to further enlighten pre-postnatal factors affecting the fetal skull base morphometrism.

Is mycophenolate mofetil an alternative agent to corticosteroids in traumatic nerve paralysis?

OBJECTIVE: The effects of an immunosuppressive agent, mycophenolate mofetil (MM), were investigated and compared with those of methylprednisolone (MP) and dexamethasone (DXM) on the traumatic nerve function. STUDY DESIGN: This is a randomized controlled animal study. MATERIALS AND METHODS: This experimental study was performed on 84 male Wistar albino rats. The rats were assigned to 12 groups each consisting of 7 animals. The groups were formed according to application of normal-dose DXM (group 1A-B), high-dose MP (group 2A-B), normal-dose MP (group 3A-B), MM (group 4A-B), and MM with high-dose MP combination therapies (group VA-B). Right sciatic nerve dissection was performed, and compound muscle action potential thresholds were recorded. The nerve was traumatized with the compression of a Jeweller forceps for 20 seconds. Posttraumatic thresholds were also recorded. The compound muscle action potential thresholds were recorded in the first and fourth weeks for the assigned groups. Then, the nerve was transected and prepared for electron microscopic and histopathologic examinations. Nitric oxide and malondialdehyde assessments were performed on both tissue and blood samples. RESULTS: Only the MM and MP+MM groups had satisfactory electron microscopic findings and were about to reach the tissue characteristics of the control animals. Despite the electrophysiologic recovery, the DXM group was found to have poor electron microscopic scoring. CONCLUSIONS: Mycophenolate mofetil has been found to be beneficial in the treatment of traumatic nerve paralysis. Although a complementary investigation is needed, this immunosuppressive agent may be an alternative to corticosteroids for the selected cases where steroid therapy is contraindicated.

Anatomical Analysis of the Eustachian Tube in the Temporal Bone Through the Middle Fossa Window.

PURPOSE: This cadaveric anatomical study aimed to explore precise morphometric measurements of the eustachian tube (ET) and adjacent structures in the middle cranial fossa, focusing on identifying reliable surgical landmarks when traditional markers are compromised due to tumors or trauma. METHODS: Twenty-two temporal bones from 11 adult cadavers (mean age: 75.70 ± 13.75 yr, range: 40-90 yr; sex: 5 females and 6 males) were dissected bilaterally. Surgical tools, including an operation microscope, endoscope, and digital caliper, were used for meticulous measurements. Parameters such as ET dimensions, distances between key points, and relevant angles were quantified, ensuring precise anatomical data. RESULTS: ET width at the foramen spinosum (FS) level, the midline level, and the eustachian orifice level were measured as 2.18 ± 0.68, 2.42 ± 0.70, and 2.30 ± 0.74 mm, respectively. The distances from the zygomatic root (ZR) to FS, ET, superior semicircular canal (SSC), and internal carotid artery (ICA) were 29.61 ± 2.56, 23.28 ± 2.61, 26.53 ± 2.56, and 32.61 ± 3.69 mm, respectively. The angles between SSC-ZR-ICA and FS-ZR-ICA were measured as 36.57 ± 10.32 and 13.63 ± 3.72 degrees, respectively. No statistical difference was found between right-left or male-female measurements ( p > 0.05). CONCLUSION: The present study offers invaluable insights for neurotological surgeons performing middle fossa approaches. ET and ZR may serve as crucial reference points, enhancing surgical orientation and minimizing risks during complex procedures. These precise anatomical data may empower surgeons, ensuring safer and more confident middle cranial fossa operations, even in challenging clinical scenarios.

The effect of trapidil and bevacizumab on tracheal anastomotic wound healing.

BACKGROUND: Although bevacizumab has deleterious effects on the healing of colonic anastomoses, trapidil improves wound healing of colonic and tracheal anastomoses. OBJECTIVE: We aimed to assess the effects of bevacizumab and trapidil on wound healing after tracheal transection. MATERIALS AND METHODS: We evaluated 35 rats divided in 5 groups: bevacizumab (Group I, n = 7), trapidil (Group II, n = 7), trapidil + bevacizumab (Group III, n = 7), controls (Group IV, n = 7), and sham (Group V, n = 7). Anastomotic healing was assessed by measurement of bursting pressure and inflammation score at the anastomotic region on the seventh day. RESULTS: The bursting pressures of Group II, Group III, and Group V were significantly higher than controls (P = 0.001, P = 0.033, and P = 0.035, respectively). Fibrosis was significantly high in the sham group when compared with the other four groups (P = 0.047). CONCLUSIONS: Although bevacizumab seems to impair anastomotic healing, trapidil can be suggested to improve tracheal anastomoses.

Location of the Tympanic Nerve Relative to the Round and Oval Windows.

BACKGROUND: The aim of the study was to measure the distance of the tympanic nerve to the oval window and round window niche in adult cadavers for evaluating its usability as an anatomical landmark during middle ear-related surgeries, including stapedotomy and cochleostomy, and for preventing its iatrogenic damage during surgical practices such as otosclerosis surgery and cochlear implantation. METHODS: The middle ears of 10 adult cadavers aged 74.70 ± 14.56 years were bilaterally dissected with the help of an endoscope and microscope to measure the distance of tympanic nerve to round window niche and oval window. RESULTS: Tympanic nerve was found as 1.60 ± 0.86 mm (range, 0-3.11 mm) and 1.55 ± 0.38 mm (range, 1.04-2.20 mm) away from round window niche and oval window, respectively. In relation to the quantitative values of these 2 distances, neither right-left nor male-female significant differences were determined (P > .05). Tympanic nerve was observed in all temporal bones. In terms of the shape and twigs of tympanic nerve, extreme variations among cadaveric temporal bones were determined. Tympanic nerve-round window niche distance between 0-1 mm was defined as type 1 (20%), between 1 and 2 mm as type 2 (45%), between 2 and 3 mm as type 3 (30%), and between 3 and 4 mm as type 4 (5%). CONCLUSION: Tympanic nerve may be vulnerable at round window niche- or oval window-related surgeries (e.g., cochleostomy).

Development of the Geniculate Ganglion in Human Fetuses.

AIM: To present the quantitative development of the geniculate ganglion (GG) in foetal cadavers. MATERIAL AND METHODS: This study focused on 60 temporal bones of 30 (15 female and 15 male) foetuses aged 18?30 weeks of gestation (mean age, 22.83 ± 3.49 weeks) to measure the length, width and area of the GG. RESULTS: According to gestational weeks and months, the ganglion length (1.21 ± 0.41 mm), width (1.03 ± 0.28 mm) and area (1.24 ± 0.61 mm < sup > 2 < /sup > ) did not change. In terms of sexes or sides, ganglion dimensions were not significantly different. Positive correlation was found between the length and width (p=0.033, r=0.276), between the length and area (p < 0.001, r=0.762) and between the width and area (p < 0.001, r=0.622). Linear functions were calculated for the ganglion area (y=0.355 + 0.039 × weeks), length (y=0.636 + 0.025 × weeks) and width (y=0.634 + 0.017 × weeks). CONCLUSION: The ganglion size did not change in foetal cadavers aged 18?30 weeks of gestation. This finding may be important for anatomists and embryologists in performing morphometric studies and understanding the development of the GG and for neurootologists and neurosurgeons in achieving greater success in skull base surgeries.

Comparison of the effects of different electrocautery applications to peripheral nerves: an experimental study.

BACKGROUND: This study was designed to investigate the effects of bipolar and mononopolar electrocauterization on peripheral nerve tissue. The comparison on the deleterious effects of the different cautery modalities and the importance of probe tip placement are evaluated using electrophysiological, electron microscopic and biochemical assessment parameters. METHODS: Ninety-eight male Wistar albino rats, each weighing 250-275 g, were randomly divided into 14 groups. Each group consisted of seven animals. Monopolar and bipolar electrocautery were performed at 15 watts. The application was performed either directly on the nerve or 1 mm lateral to the longitudinal axis of the nerve for 'near the nerve groups', respectively. RESULTS: The electrophysiological findings showed that the mean amplitudes were at the lowest value in the first day for all the groups. At the end of the 3rd week, we recognised that the electrophysiological recovery continued. Electron microscopic evaluation showed myelin disruption in all groups. Myelin disruption of healthy neurons was at the highest level in the 1st day of application in accordance with the electrophysiological findings. Biochemical evaluation revealed statistical significance between the control and the two of the 'near the nerve groups' (GIII and GV) for NO (nitrite and nitrate) serum level. CONCLUSION: The data of the present study might suggest that electrocautery, independent of the type and form of application, may result in significant damage in histological and electrophysological basis. Although the relative proportions cannot be ascertained, the time course of recovery suggests that both axon and myelin damage have occurred. The probable electrocautery damage may be of substantial importance for the situation that the nerves are displaced by tumor masses or atypical neural traces.