Microsurgical anatomy of the craniovertebral junction: An anatomical study with far lateral approach

Öz

Aim: The far lateral approach is indicated for lesions located anterior to the dentate ligament between the lower third of the clivus and the upper part of the C2 body. Modified subgroups have also been described for increasing the exposure of level of this highly crowded anatomical region. We present an anatomical and clinical study demonstrating the feasibility of a far lateral approach that provides access to multiple lesions at the craniovertebral junction. Material and Methods: Four formalin-fixed and mummified adult cadaver specimens were used in this study. Skin incision, followed by careful dissection of various muscle groups, exposed the suboccipital triangle. C1 and C2 posterior arches were removed to reveal the course of the vertebral artery. Finally, suboccipital craniectomy was performed to reach craniovertebral junction and associated regional anatomy was openly exposed. Results: Numerous anatomical structures that have vast clinical significance provides the delicacy and complexity of this region. Vertebral artery, hypoglossal nerve, spinal accessory nerve, dentate ligaments, first and second cervical neural roots and brainstem were carefully exposed and identified during the dissection process. Conclusion: Far lateral approach increases the surgical dominance and maneuverability of the pathologies located in craniovertebral junction and upper cervical spine. With this approach, surgical difficulties of the region can be overcome with the development of anatomical knowledge and technical infrastructure. Knowledge of the microtopographic surgical anatomy of this region is the fundamental element to achieve an effective surgery.

Anahtar Kelimeler

• craniovertebral junction
• microsurgery
• anatomy
• cadaver
• far lateral approach

Kraniovertebral bileşkenin mikrocerrahi anatomisi: posterolateral yaklaşımla anatomik çalışma

Öz

Amaç: Kranioservikal posterolateral yaklaşım, klivusun alt üçte biri ile C2 gövdesinin üst kısmı arasındaki dentat ligamanın önünde yer alan lezyonlar için endikedir. Bu oldukça kalabalık anatomik bölgenin açığa çıkarılma seviyesini artırmak için bu yaklaşım modifiye edilmiş alt grupları da tanımlanmıştır. Bu makalede, kraniovertebral bileşkedeki lezyonlara erişim sağlayan posterolateral yaklaşımın uygulanabilirliğini gösteren anatomik ve klinik bir çalışma sunuyoruz. Gereç ve Yöntemler: Bu çalışmada formalinle sabitlenmiş ve mumyalanmış dört yetişkin kadavra örneği kullanıldı. Cilt insizyonunu takiben çeşitli kas gruplarının dikkatli diseksiyonu suboksipital üçgeni açığa çıkardı. Vertebral arterin seyrini göstermek için C1 ve C2 arka arkusları çıkarıldı. Son olarak kraniovertebral bileşkeye ulaşmak için suboksipital kraniyektomi yapıldı ve ilişkili bölgesel anatomi açık bir şekilde ortaya kondu. Bulgular: Geniş klinik öneme sahip çok sayıda anatomik yapı, bu bölgenin hassaslığını ve karmaşıklığını sağlamaktadır. Diseksiyon işlemi sırasında vertebral arter, hipoglossal sinir, spinal aksesuar sinir, dentat ligamanlar, birinci ve ikinci servikal nöral kökler ve beyin sapı dikkatlice açığa çıkarılıp tanımlandı. Sonuç: Kranioservikal posterolateral yaklaşım, kraniovertebral bileşke ve üst servikal omurgada yer alan patolojilerin cerrahi hakimiyetini ve manevra kabiliyetini arttırır. Bu yaklaşımla anatomik bilgi ve teknik altyapının geliştirilmesi ile bölgenin cerrahi zorlukları aşılabilir.

Anahtar Kelimeler

• kraniyovertebral bileşke
• mikrocerrahi
• anatomi
• kadavra
• posterolateral yaklaşım

Kaynakça

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