Mustafa Bozbuga

Morphometric evaluation of subaxial cervical vertebrae for surgical application of transpedicular screw fixation.

Study Design. A morphometric evaluation of pedicle projections in 29 cervical spinal columns (C3–C7) for three-dimensional surgical anatomy for safe surgery was proposed. Objective. In this study, pedicles and intimate structures of the subaxial vertebrae from C3 to C7 were evaluated to provide some morphometric data for cervical transpedicular screw fixation. Summary of Background Data. Detailed knowledge of surgical anatomy and variation of the subaxial vertebrae is a must for safe and effective surgery of the region. Although there are several clinical studies of transpedicular fixation, few studies have been performed on cervical pedicle measurements and their projection. Methods. In 29 dried bone cervical spinal columns (C3–C7), pedicle dimensions (pedicle height, width, length), measurements of lateral mass and pedicle length distance and pedicle axis length, investigation of distances of superior facet-midpedicle axis and inferior facet-midpedicle axis, and transverse and sagittal angles of the pedicles were performed in linear and angular measurements. Results. The obtained data from the series revealed that the mean values were approximately ranging from 6.7 to 7.2 mm for pedicle height, 4.4 to 4.9 mm for pedicle width, 5.3 to 6.2 mm for pedicle length, 15.3 to 16.0 mm for lateral mass and pedicle length, 22.2 to 27.7 mm for pedicle axis length, 3.8 to 5.3 mm for superior facet-midpedicle axis distance, 9.9 to 12.0 mm for inferior facet-midpedicle axis distance, 42.3° to 51.5° for transverse angle, and 5.2° to 14.1° for sagittal angle. Conclusions. Linear measurements of pedicle dimensions and also axial angles from horizontal and vertical planes may provide some anatomic limitations for subaxial cervical transpedicular screw fixation, and also contribute to the safety of the surgical procedure. One should also rely on tomographic data and computer-assisted guidance systems.

Posterior fossa epidural hematomas: observations on a series of 73 cases

Abstract The posterior fossa is an uncommon site for epidural hematomas. Clinical progress is silent and slow, but the deterioration is sudden and quick to become fatal if not promptly treated. Early recognition is therefore extremely important. The recommended treatment for posterior fossa epidural hematoma is surgical evacuation soon after the diagnosis, since the posterior fossa contains vital structures. However, conservative management under close clinical and radiological supervision can be applied in patients without mass effect. In our study, a review of 73 cases with posterior fossa epidural hematoma among a total number of 737 patients with epidural hematoma is presented, and a new neuroradiological classification is proposed in order to determine the appropriate type of treatment. In this series, 14 patients were treated conservatively, while 59 required surgery. The conservatively treated 9 pediatric and 5 adult patients, and 51 of the 59 surgically treated cases, in other words a total of 65 of the 73 patients, showed excellent recovery; 4 patients treated surgically had a moderate disability, and 4 patients died (overall mortality 5.4%). The critical factors influencing outcome were the neuroradiological class, the level of consciousness just before the operation, and the other systemic and/or intracranial traumatic lesions. In this study, the critical observation was that the neuroradiological findings were earlier, more reliable and predictive than the clinical findings. Therefore, based upon the obliteration of perimesencephalic cisterns and/or displacement of the fourth ventricle, a new neuroradiological classification was designed for decision-making in management.

Evaluation of Mild Head Injury in a Pediatric Population

Approximately 5 million children present to emergency departments, seeking care for head injuries, each year, and 80% of these children are classified as cases of mild head injury. Due to the huge number of patients and low frequency of intracranial lesions in this group, obtaining a computed tomography scan for each and every patient is a significant economic problem. This study was conducted to identify the clinical parameters and the radiographic findings that may be associated with intracranial lesions in children with mild head injury. 421 patients, with a Glasgow Coma Scale score of 15 and without any focal neurological deficit, were studied. Intracranial lesion was noted in 37 cases (8.8%). Sensitivity of a plain radiogram was 43.2%, and specificity was 93%. An intracranial pathology was demonstrated in 28.9% of the patients with a linear skull fracture. The only clinical parameters associated with an increase in the frequency of detection of intracranial lesions were posttraumatic seizures and loss of consciousness. Age, sex, headache, vomiting and scalp lacerations were not associated with a higher frequency. Even when patients with a history of loss of consciousness or posttraumatic seizure were subtracted from the study group, intracranial lesions were noted in 4.1% of the cases, and in 1.8% neurosurgical intervention was required. Computed tomography is the gold standard in the evaluation of pediatric patients with mild head trauma, and every child who has experienced a head injury should undergo a cranial computed tomography evaluation, even if he or she appears in perfect health.

Surface anatomy of the posterolateral cranium regarding the localization of the initial burr-hole for a retrosigmoid approach

Knowing the location of the venous sinuses is essential for the localization of the initial burr–hole for a retrosigmoid approach, in order to avoid inadvertent entry into the venous sinuses and limitation of the size of the bony opening. In this anatomic study, external landmarks of the posterolateral cranium have been studied, in order to reveal the relationship with the venous sinuses. Eighty-four dried adult human skulls were studied and study of both sides yielded 168 sides. Morphometric measurements of the posterolateral cranium have been performed and relations of the external landmarks with the venous sinuses have been studied. The anatomic position of the asterion was variable. The superior nuchal line was roughly parallel and below the lower margin of the sulcus of transverse sinus in all specimens. The sigmoid sinus, between the superior and inferior bends, seemed to descend along an axis defined by the junction of the squamosal–parietomastoid suture and the mastoid tip, in a slightly oblique fashion. In conclusion, a burr–hole placed just below the superior nuchal line and posterior to the axis defined by the mastoid tip and the squamosal-parietomastoid suture junction is appropriate for both avoiding inadvertent entry into the sinus and limiting the size of the craniotomy.

Evaluation of the bony landmarks in transcondylar approach

Background. The aim of this study is to define the anatomic landmarks which are necessary for transcondylar approach and to determine the importance of these structures during surgical resection. Methods. 56 dry skulls were included in this study. Landmarks were detected. Some distances and angles, which were determined before, were measured and the anatomical structures were observed. 21 parameters were examined and analysed in totally 56 dry skulls using 56 foramen magnum, 112 hypoglossal canal and 112 occipital condyles. The landmarks which were used were the anterior and posterior borders of the occipital condyle, the medial and lateral margin of the occipital condyle, basion, opisthion, hypoglossal canal and posterior condylar canal. The measurements were made separately for the right and left sides. Results. The mean length of the occipital condyle was found as 23.1 mm. The distance betweeen the intracranial edge of the hypoglossal canal and anterior margin of the occipital condyle was measured as 11.2 mm in both sides. The distance betweeen the intracranial edge of the hypoglossal canal and posterior margin of the occipital condyle was measured as 12.5 mm at the right side and 12.6 mm at the left one. The mean length of the hypoglossal canal was measured as 10.5 mm at the right side and 10.6 mm at the left one. 14 hypoglossal canals were divided into two compartments by a septum. Conclusions. In transcondylar approach, the anatomical landmarks should be well known in order to make a safe occipital condyle resection. The distance betweeen the intracranial edge of the hypoglossal canal and posterior margin of the occipital condyle is important for a safe occipital condyle resection, and it was found to be 12.55 ±0.05 mm in our study. Approximately 12 mm occipital condyle resection can be made without giving damage to the neural tissue. This value is appropriate to the ½ of the occipital condyle.

Cerebral tuberculoma mimicking high grade glial tumor.

Tuberculosis has been an important public health problem in both developing and develop nations. Tuberculosis of the central nervous system is rare. Tuberculosis meningitis and tuberculoma are the two most important manifestations of tuberculosis of the CNS. Intracranial tuberculomas may be solitary or multiple. Solitary tuberculomas may be indistinguishable from cranial abscess or primary brain tumor. It is necessary to rule out tuberculoma in patients with intracranial mass lesions. We present a case of tuberculoma mimicking a high grade glial tumor on magnetic resonance imaging and clinical presentation. A 30-year-old woman presented with one-month history of epilepsy. Cranial magnetic resonance imaging showed a left occipital peripheral ring-enhanced lesion with central necrosis. There was a strong suspicion of glial tumor. The lesion was totally excised with left occipital craniotomy. Histological examination of mass revealed a tuberculoma. The patient was treated with antituberculous chemotherapy.

Hydatid cyst of the craniocervical junction: case report.

OBJECTIVE AND IMPORTANCE:Although rare in developed countries, hydatid disease is a serious parasitic infection in endemic areas. Spinal disease most commonly involves the thoracic region, and involvement of the upper cervical spine is extremely rare. In this report, a case of hydatid disease involving the craniocervical junction is presented, along with a review of the literature. CLINICAL PRESENTATION:A 44-year-old man presented with the complaint of neck pain. The results of his physical and neurological examinations were within normal ranges, except for pain exacerbated by neck motion and spasm of the cervical musculature. Magnetic resonance imaging demonstrated a cystic lesion involving the odontoid process and body of C1 and C2, with thin and regular cyst walls and cyst contents similar in intensity to that of cerebrospinal fluid. The results of serological tests performed with the suspected diagnosis of hydatid disease were positive. INTERVENTION:The patient initially underwent surgery to provide stabilization of the craniocervical junction, using autogenous bone graft and sublaminar wiring from the occiput to C3 via a posterior approach. The cyst was approached via a transoral route, using a U-shaped pharyngeal incision. There were no neurological deficits after surgery. Postoperative magnetic resonance imaging scans confirmed complete excision of the cyst, and the patient was discharged on the 12th postoperative day. He received six cycles of albendazole treatment, each consisting of 28 days with an intervening drug-free period of 2 weeks. Magnetic resonance imaging scans performed 1 year after surgery revealed the patient was still disease-free. CONCLUSION:Hydatid disease should be considered in the differential diagnosis of spinal cord compression, especially in endemic areas. Although the chance of obtaining a cure is unlikely, radical surgery coupled with antihelminthic therapy seems to provide long-lasting relief.

Primary cerebellopontine angle craniopharyngioma in a patient with Gardner syndrome

Craniopharyngiomas usually involve the sella and suprasellar space. Ectopic craniopharyngiomas have rarely been reported at the cerebellopontine angle (CPA). We report a rare primary craniopharyngioma of the CPA without extension into the sellar region. The lesion was initially detected by MRI during investigation of multiple scalp fibromas. Multiple osteomas of the skull and face were detected 2years later, and colonic adenomatous polyposis was detected 4years later; typical features of Gardner syndrome. This is the third report of a primary CPA craniopharyngioma in a patient with Gardner syndrome.

Bilateral Lhermitte-Duclos disease

Lhermitte-Duclos disease (LDD) is a pathologic entity with progrediating, diffuse hypertrophy chiefly of the stratum granulosum of the cerebellum. Typically LDD is a unilateral lesion of the cerebellum or in vermis. Here we report a case of LDD with bilateral lesions of cerebellar hemispheres managed surgically. A 28-year-old woman presented with one-year history of progressive headache, nausea, vomiting, and blurred vision. Neurologic examination revealed a bilateral mild papilledema, mild dysmetria, and dysdiadochokinesia. The cerebellar lesions caused moderate mass effect in posterior fossa with hydrocephalus, and Chiari type I malformation. We performed the suboccipital-retrosigmoid approach, and removed completely the left intracerebellar mass. Symptoms related to elevated intracranial pressure disappeared in a short period postoperatively.

The relation between surgical cleavage and preoperative neuroradiological findings in intracranial meningiomas

BACKGROUND Meningiomas are generally benign masses, and in many cases they do not invade the brain. Therefore their potential to provide cures is high. The most important cause of the development of recurrence in the post-operative period is subtotal resection. Any information that will allow us to perform total mass resection will be beneficial in terms of long-term good clinical procedure. Our aim in this study is to obtain the radiological data from which we can obtain accurate information in terms of the surgical cleavage between the tumor and parenchyma during the surgical planning of the meningiomas. METHODS We evaluated 85 cases with intracranial meningioma that were treated by the same microsurgical technique. All posterior fossa and skull base meningiomas were not included in the study. RESULTS Tumor size was smaller than 3 cm in 19 cases, between 3 and 6 cm in 46 cases, and bigger than 6 cm in 20 cases. The cleavage line between the tumor capsule and the cortex underneath was extrapial in 32 cases, subpial in 29 cases, and mixed in 24 cases. Dominant arterial supply was dural in 46 cases. Thirty-three cases were predominantly mixed and 6 cases were predominantly corticopial. At magnetic resonance images, 16 of 28 cases which showed clear tumor-cortex interface, had an extrapial cleavage line. CONCLUSIONS When surgical treatment of intracranial meningiomas are considered, it is necessary to examine if there is a surgically safe border between the cortex underneath in the preoperative images. It can be concluded that it is appropriate to operate small meningiomas which are on the sensitive regions of the brain when they are in their earlier stages and still have an extrapial cleavage.