Assessment of the Anterior Clinoid Process and Optic Strut in Chiari Malformation Type I: A Computed Tomography Study.

Objective This study aimed to evaluate morphological features of the anterior clinoid process (ACP) and the optic strut (OS) in Chiari malformation Type I (CM-I). Methods The study universe consisted of computed tomography images of 41 CM-I patients and 45 normal subjects. Comparison of the parameters for CM-I and the control group was performed with the Student's t -test. A " p < 0.05" was accepted as the significance level. Results ACP length was smaller in CM-I than the control group ( p < 0.001). In contrast to ACP length, ACP angle ( p < 0.001), OS length ( p = 0.022), and the distance between ACP and OS ( p = 0.020) were found greater in CM-I in comparison to the control group ( p < 0.05). ACP width ( p = 0.233) and OS width ( p = 0.376) were similar in both groups. ACP pneumatization in CM-I group was found as 12.20%, whereas in the control group as 8.90%. Two different types about the pneumatization were identified in CM-I group (Type 1: 4.9% and Type 2: 7.3%), whereas three different types in the control group (Type 1: 3.3%, Type 2: 4.4%, and Type 3: 1.1%). Relative to ACP, three different types about OS position were identified in CM-I group (Type C: 31.70%, Type D: 64.60%, and Type E: 3.70%) and the control group (Type C: 7.80%, Type D: 64.40%, and Type E: 27.80%). Conclusion Shorter ACP, wide-angled ACP, longer OS, and more anteriorly located OS were found in CM-I group compared with the normal group. Our findings showed that the pneumatization of ACP was not affected by CM-I.

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.

A Computed Tomography Study of the Prechiasmatic Sulcus Anatomy in Children.

PURPOSE: To investigate the characteristics of the prechiasmatic sulcus in children aged between 1-20 years. METHODS: Patient files of 200 children admitted to the university hospital on 2019 were analyzed, retrospectively. The computed tomography images of patients were used to obtain anatomical knowledge containing prechiasmatic sulcus types and dimensions. RESULTS: The measurements related to the sulcal length (6.94 ± 1.25 mm) and sulcal angle (31.01 ± 18.13°) showed that the sulcal length did not alter in children between 1 and 20 years, whereas the sulcal angle did not vary from infancy to prepubescent period, but it was decreasing in postpubescent period. In 29 patients, the sulcal length was observed to divide into 2 parts with an evident angle. The interoptic distance and planum length were found as follows: 14.70 ± 2.85 mm and 14.84 ± 4.12 mm, respectively. The order of PS types was observed as type 4 (26.5%, 53 cases) > type 2 (26%, 52 cases) > type 1 (24%, 48 cases) > type 3 (23.5%, 47 cases). CONCLUSIONS: The sulcal length did not vary in children, whereas the sulcal angle decreased with an irregular pattern. The sulcal angle decreased after prepubescent period, possibly due to the sphenoid sinus pneumatization and spheno-occipital synchondrosis. The sulcal length angle mostly in infants and young children may cause surgical orientation difficult during the resection of tumors using transcranial approaches.

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.

The Comparison of the Right and Left Sigmoid Sinus Cross-Sectional Areas in Fetal Period and the Factors Affecting the Venous Dominance.

OBJECTIVES: Skull base is an important and a challenging area for surgeons. Success in skull base surgery depends on various factors such as pre-operative evaluation, appropriate surgical technique, anesthesia duration, intraoperative neuromonitorization and wound care. MATERIALS AND METHODS: This study was performed in the Anatomy dissection laboratory of M.U. Medical Faculty (Ethical committee approval number 2010-103). Twelve fetuses between 17-33 gestational weeks fixed with formaldehyde were enrolled to the study. RESULTS: This study was planned to investigate the cross sectional areas of the sigmoid sinus in three levels to compare the right-left sides and the probable relationship among the levels in fetuses to further delineate the developmental factors on jugular foramen asymmetry. The cross-sectional measurements of sigmoid sinus lumen were done on 3 levels which are described as A1 level; sinodural angle, A2 level; the midpoint between the sinodural angle and endocranial orifice and A3 level as the entrance (endo-cranial orifice) of the jugular foramen. There is a strong positive correlation between left (L) A1 and L A2 and also the same for L A1 and right (R) A2. These strong and positive correlations are all valid between L A2-L A3, L A2-R A2, L A2-R A3, L A3-R A3, R A1-R A2. CONCLUSION: Multicenter studies would be beneficial to investigate the topic with greater number of fetuses also on the different regions for genetic differences.

Morphometric Features of the Latissimus Dorsi Muscle in Fetal Cadavers With Meningomyelocele for Prenatal Surgery.

PURPOSE: Latissimus dorsi (LD) flaps are frequently used in the prenatal meningomyelocele (MMC) repairs; on that basis, this study aims to reveal the morphometric features of LD, thoracodorsal artery (TDA) and nerve (TDN) in fetal cadavers with MMC defects, with an anatomical perspective. METHODS: The study was conducted on 7 formalin-fixed human fetal cadavers (4 males and 3 females) with MMC defects, aged from 18 to 27 weeks of gestation. The size of LD, TDA, and TDN including their area, length, and width were measured by a digital caliper and digital image analysis software. Our direct measurements were compared with the corresponding estimations of a previous study in the literature which provides regression formulae based on gestational age. RESULTS: The fetal cadavers with MMC had bilateral LD. No significant differences were found in the numerical data of anatomical structures between the sides or the sexes. LD size (ie, area, length and width) was approximately 3% to 10% smaller in the fetuses with MMC defects than that of the normal fetuses. Unilateral LD flap in a 22-week-old fetus with a large MMC was evaluated as insufficient to close the defects. CONCLUSION: Ten percent shrinkage in the area of LD might be too critical to be disregarded by surgeons during the closure of MMC defects. The dimensional findings about LD (area, length, and width) may be helpful in planning of LD flap harvesting for the repairs of MMC.

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.

Rare Cause of Acute Tetraplegia and Respiratory Arrest: Cervicomedullary Neuroenteric Cyst in a Child: Case Report.

BACKGROUND: Neuroenteric cysts (NCs) are benign, rare congenital lesions which are most commonly found in the lower cervical and upper thoracic segments. Even though these are benign lesions, it may present with fatal neurologic deterioration particularly in pediatric patients. CASE REPORT: We here report a 16-year-old boy who has unique manifestation with acute tetraplegia and respiratory arrest in emergency room. According to English literature, this is the first case of cervicomedullary intradural neuroenteric cyst which causes acute tetraplegia and respiratory arrest in a child. CONCLUSION: The NCs can be manifested with unpredictable, life threating clinical presentation. The exact pathophysiology of an acute neurological deterioration is still unclear, however prolonged latent period with minor symptom should be considered carefully in child population.

Management of occipitocervical junction and upper cervical trauma.

OBJECTIVE: The treatment modality of occipitocervical junction (OCJ) and upper cervical traumas carries great importance because of unique form of bone, complex ligamentous, and neurovascular structure. MATERIALS AND METHODS: Eighty-eight patients were admitted to Mersin University Department of Neurosurgery between January 2007 and January 2017 for injuries of the OCJ and upper cervical spine and evaluated retrospectively. In the group, there were 60 male, 28 female patients in the mean age of 42.9 (18-87) years. Among those, 2 occipital condyle fractures, 28 C1 fractures (26 isolated and 2 with transverse ligament injury), 9 combined C1/C2 fractures, 6 rotatory C1/C2 dislocations, and 43 C2 fractures (32 odontoid, 5 Hangman's, and 6 miscellaneous fractures) were diagnosed. In addition to clinical cases, ten cadavers were used to study the OCJ in a step-wise manner. RESULTS: Occipital condyle fractures, isolated C1 fractures, and rotatory C1/C2 dislocations were treated conservatively. Two patients with C1 fracture including transverse ligament injury were operated in one of the methods of C1-C2 fusion which is posterior sublaminar wiring. Five patients having Type II odontoid fracture were treated surgically. One instable Hangman's fracture patient was treated as anterior cervical discectomy and fusion. CONCLUSIONS: Cases with isolated C1 fracture with intact transverse ligament should be conservatively treated without surgical approach. Atlas fractures with transverse ligament rupture, odontoid Type II fractures with dislocation >6 mm, and unstable Hangman's fractures required surgical treatment. Vital neurovascular, ligamentous, and accompanying bone structures should be evaluated for diagnosis and treatment modality. In addition, patient's health status, patient's treatment preference, and surgical team experience are the affecting factors for the decision of surgery.

Clinical course of the untreated calcified big cerebellar liponeurocytoma.

Cerebellar liponeurocytoma (CLN) is a very rare tumor of central nervous system, classified as glioneuronal tumor by the latest classification of World Health Organization (WHO) in 2016. There are limited data in the literature about biologic behavior, growth pattern and radiological features of this tumor. In this case report, we operated a big calcified CLN patient who had denied any surgical procedures suggested by an another institute and had been followed for 4 years.

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.

Reconstruction of a Marjolin Ulcer Defect of the Scalp Invading Brain and Causing Brain Abscess Formation Using Free Latissimus Dorsi Flap.

Marjolin ulcers are known as aggressive malignant tumors that mostly arise over chronic wounds and cutaneous scars. Brain abscess is a serious medical condition that requires surgical drainage along with antibiotic treatment. Here, we report a case with a Marjolin ulcer located over the right parietal bone with intracranial abscess formation along with tumor invasion into brain parenchyma. This patient was a 64-year-old man and had a 4 × 4 cm open wound on his scalp from which a purulent discharge was coming. This wound required surgical excision with security margins, resection of bone, evacuation of the cystic cavity, and excision of the walls of the cystic cavity, which were invaded by the tumor. Duraplasty and reconstruction of the defect with a free lattisimus dorsi flap are performed. To the best of our knowledge, the case reported here is unique because of the formation of brain abscess in the background of a long-lasting Marjolin ulcer invading brain parenchyma. It must be remembered that on the background of cutaneous scars located over the scalp, a Marjolin ulcer may develop, and if left untreated, tumor cells may invade even the brain parenchyma. Long-term asymptomatic brain infections may also accompany the given scenario, and complicate differential diagnosis.