Anatomical Study of Important Anatomical Landmarks in The Skull in Relation to External Occipital Protuberance

Abstract Purpose There is no systematic description of primary anatomical landmarks that allow a surgeon to reliably and safely navigate the superior and posterior mediastinum’s fat tissue spaces near large vessels and nerves during video-assisted endothoracoscopic interventions in the prone position of a patient. Our aim was to develop an algorithm of sequential visual navigation during thoracoscopic extirpation of the esophagus and determine the most permanent topographic and anatomical landmarks allowing safe thoracoscopic dissection of the esophagus in the prone position. Methods The anatomical study of the mediastinal structural features was carried out on 30 human cadavers before and after opening the right pleural cavity. Results For thoracoscopic extirpation of the esophagus in the prone position, anatomical landmarks are defined, their variants are assessed, and an algorithm for their selection is developed, allowing their direct visualization before and after opening the mediastinal pleura. Conclusion The proposed algorithm for topographic and anatomical navigation based on the key anatomical landmarks in the posterior mediastinum provides safe performance of the video-assisted thoracoscopic extirpation of the esophagus in the prone position.

Download Full-text

An anatomical study of the superficial palmar communicating branch between the median and ulnar nerves

Journal of Hand Surgery (European Volume) ◽

10.1177/1753193415576460 ◽

2015 ◽

Vol 41 (2) ◽

pp. 191-197 ◽

Cited By ~ 6

Author(s):

S. Sulaiman ◽

R. Soames ◽

C. Lamb

Keyword(s):

Anatomical Study ◽

Metacarpophalangeal Joint ◽

Anatomical Landmarks ◽

Risk Area ◽

Surgical Interventions ◽

Total Distance ◽

Flexor Retinaculum ◽

Communicating Branch ◽

Branching Patterns ◽

Operative Complications

The palmar communicating branch between the median and ulnar nerves was investigated in 98 hands with the aim of outlining its most common branching patterns and describing its relationship to well-defined anatomical landmarks, including the bistyloid line, wrist crease and flexor retinaculum. Five branching patterns were identified and classified based on their proximal and distal attachments. The palmar communicating branch was found to lie between 26%–79% of the total distance between the metacarpophalangeal joint of the long finger and the wrist crease, and 35%–75% of the total distance between the metacarpophalangeal joint of the long finger and the middle of the bistyloid line. With the aid of the morphometric indices obtained from this study, a risk area where the palmar communicating branch is most likely to be found is outlined. Knowledge of the branching patterns and location of the palmar communicating branch can help clinicians to better assess variations in the patterns of sensation, preserve the nerve during surgical interventions to the palm and better assess post-operative complications involving the branch.

Download Full-text

Endoscopic Transorbital Approaches to Anterior and Middle Cranial Fossa: A Laboratory Investigation on Surgical Anatomy and Potential Routes

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0040-1713101 ◽

2020 ◽

Author(s):

Beniamino A. Nannavecchia ◽

Mario Ganau ◽

Hélène Cebula ◽

Antonino Scibilia ◽

Maria T. Bozzi ◽

...

Keyword(s):

Anatomical Study ◽

Middle Cranial Fossa ◽

Surgical Anatomy ◽

Anatomical Landmarks ◽

Orbital Cavity ◽

New Horizons ◽

Endoscopic Transorbital ◽

Cranial Fossa ◽

Alternative Routes ◽

Anatomy Knowledge

Abstract Background Transorbital neuroendoscopic (TONES) approaches promise to open up new horizons for skull base surgery, offering alternative routes to reach the anterior and middle cranial fossa (ACF and MCF, respectively). Objective The aim of this anatomical study is to acquire new surgical anatomy knowledge and exploit it for the refinement of TONES approaches, as an alternative to open surgery, to reduce the distance to the target, and the risk of neurovascular lesions in pathological conditions extending beyond the orbital cavity. Materials and Methods Six head specimens (12 orbits) were studied/dissected. The orbit was approached and divided in a four clockwise quadrants manner to simulate three transconjunctival routes: the precaruncular (PC), preseptal (PS), and lateral retrocanthal (LRC), and one transpalpebral route—the superior eyelid crease (SLC). The boundaries and the most important anatomical landmarks were identified and are herein duly detailed with particular attention to the neurovascular structures encountered in each of those routes. Results The dissections showed that the PC approach facilitates the treatment of optic nerve and frontal sinus pathologies, whereas LRC appears safer to reach ACF and MCF allowing for a free multiplanar working channel (up to 180 degrees) to the floor, roof, and lateral-to-medial walls. Conclusion The plane of tendon lateral canthal's insertion and the sphenofrontal suture (SFS) were identified as the key anatomical landmarks for TONES approaches. Further studies are warranted to establish a practical clinical algorithm based on the anatomical four clockwise quadrants herein implemented/proposed, and the key surgical landmarks identified.

Download Full-text

Decompression of the superficial peroneal nerve: clinical outcomes and anatomical study

Journal of Neurosurgery ◽

10.3171/2016.1.jns152454 ◽

2017 ◽

Vol 126 (1) ◽

pp. 330-335 ◽

Cited By ~ 3

Author(s):

Michael J. Franco ◽

Benjamin Z. Phillips ◽

Gopal R. Lalchandani ◽

Susan E. Mackinnon

Keyword(s):

Peroneal Nerve ◽

Treatment Options ◽

Linear Regression Analysis ◽

Anatomical Study ◽

Lateral Malleolus ◽

Anatomical Landmarks ◽

Superficial Peroneal Nerve ◽

Preoperative Pain ◽

Vas Score ◽

The Impact

OBJECTIVE The authors of this study sought to determine the outcomes of patients undergoing superficial peroneal nerve (SPN) release to treat lower-extremity pain and describe consistent anatomical landmarks to direct surgical planning. METHODS This retrospective cohort study examined 54 patients with pain in the SPN distribution who were treated with decompression between 2011 and 2014. Patients rated pain and the effect of pain on quality of life (QOL) on the visual analog scale (VAS) from 0 to 10. Scores were then converted to percentages. Linear regression analysis was performed to assess the impact of the preoperative effect of pain on QOL, age, body mass index (BMI), and preoperative duration of pain on the postoperative effect of pain on QOL. Measurements were made intraoperatively in 13 patients to determine the landmarks for identifying the SPN. RESULTS A higher BMI was a negative predictor for improvement in the effect of pain on QOL. A decrease in pain compared with the initial level of pain suggested a nonlinear relationship between these variables. A minority of patients (7 of 16) with a preoperative pain VAS score ≤ 60 reported less pain after surgery. A large majority (30 of 36 patients) of those with a preoperative pain VAS score > 60 reported improvement. Intraoperative measurements demonstrated that the SPN was consistently found to be 5 ± 1.1, 5 ± 1.1, and 6 ± 1.2 cm lateral to the tibia at 10, 15, and 20 cm proximal to the lateral malleolus, respectively. CONCLUSIONS A majority of patients with a preoperative pain VAS score > 60 showed a decrease in postoperative pain. A higher BMI was associated with less improvement in the effect of pain on QOL. This information can be useful when counseling patients on treatment options. Based on the intraoperative data, the authors found that the SPN can be located at reliable points in reference to the tibia and lateral malleolus.

Download Full-text

Anatomical study of the pterygopalatine fossa using an endoscopic endonasal approach: spatial relations and distances between surgical landmarks

Journal of Neurosurgery ◽

10.3171/jns.2007.106.1.157 ◽

2007 ◽

Vol 106 (1) ◽

pp. 157-163 ◽

Cited By ~ 37

Author(s):

Domenico Solari ◽

Francesco Magro ◽

Paolo Cappabianca ◽

Luigi M. Cavallo ◽

Amir Samii ◽

...

Keyword(s):

Skull Base ◽

Anatomical Study ◽

Spatial Relations ◽

Pterygopalatine Fossa ◽

Direct Access ◽

Anatomical Landmarks ◽

Endoscopic Endonasal Approach ◽

Endonasal Approach ◽

Endoscopic Endonasal ◽

Invasive Approach

Object The pterygopalatine fossa is an area that lies deep within the skull base. The recent extensive use of the endoscopic endonasal approach has provided neurosurgeons with a method to reach various areas of the skull base through a less invasive approach than traditional transcranial or transfacial approaches. This study aims to provide neurosurgeons with new data concerning direct endoscopic measurements and precise anatomical topography features of the pterygopalatine fossa. Methods An anatomical dissection of six fixed cadaver heads (12 pterygopalatine fossae) was performed to analyze spatial relationships and distances between the most important neurovascular structures in this region, and to estimate the size of the endoscopic surgical field for operations in this area. The endoscopic endonasal approach offers direct access to the pterygopalatine fossa through its anteromedial walls. Conclusions Using an endoscopic endonasal approach makes it possible to identify all of the anatomical landmarks of the pterygopalatine fossa and almost all of the contiguous skull base areas.

Download Full-text

The Longissimus Capitis Insertion as a Superficial Landmark for the Sigmoid Sinus: An Anatomical Study

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0040-1716890 ◽

2020 ◽

Author(s):

Joe Iwanaga ◽

Koichi Watanabe ◽

Pervez A. Khan ◽

John D. Nerva ◽

Peter S. Amenta ◽

...

Keyword(s):

Attachment Site ◽

Anatomical Study ◽

Sigmoid Sinus ◽

Mastoid Process ◽

Anatomical Landmarks ◽

Knowledge Use ◽

Tendon Insertion ◽

Inferior Border ◽

Burr Holes ◽

Made In

Abstract Objective Many external anatomical landmarks have been used for approximating deeper, intracranial structures. Herein, we evaluate the attachment of the longissimus capitis (LC) on the mastoid process as a landmark for the underlying sigmoid sinus. Methods Adult cadavers underwent dissection of the posterior occiput with special attention to the attachment of the LC muscle. Once the periphery of the muscle's tendon of attachment was determined, a burr hole was made in this area and evaluated internally for its relationship to the sigmoid sinus. Results From an intracranial view, burr holes on all sides were over the sigmoid sinus and just slightly lateral to the center of the sinus. The distance from the midline to the medial border of the insertion of the LC had a mean of 63.0 ± 7.2 mm. The width of the tendon of insertion of the LC on the mastoid process had a mean of 17.6 ± 5.7 mm. The length of the tendon insertion of the LC had a mean of 14.7 ± 4.7 mm. The distance from the inferior border of the insertion of the LC to the tip of the mastoid process had a mean of 6.2 ± 4.5 mm. Conclusion To our knowledge, use of the attachment site of the LC on the mastoid process as an external landmark for the underlying sigmoid sinus has not previously been reported. Based on our cadaveric findings, the sigmoid sinus is centered under the attachment of the LC regardless of the width of its tendon.

Download Full-text

Projection of the A1-Pulley of the Thumb onto Superficial Anatomical Landmarks: An Anatomical Study and a Useful Guide to Surgeons

Indian Journal of Orthopaedics ◽

10.1007/s43465-021-00397-3 ◽

2021 ◽

Author(s):

Angelika Maria Schwarz ◽

Georg Lipnik ◽

Ulrike Maria Schwarz ◽

Marco Johannes Maier ◽

Andreas Heinrich Weiglein ◽

...

Keyword(s):

Anatomical Study ◽

Anatomical Landmarks ◽

A1 Pulley

Download Full-text

Middle Cranial Fossa Approach: Anatomical Study on Skull Base Triangles as a Landmark for a Safe Anterior Petrosectomy

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0039-1696957 ◽

2019 ◽

Author(s):

Pasquale Anania ◽

Rosa Mirapeix-Lucas ◽

Gianluigi Zona ◽

Alessandro Prior ◽

Carlos Asencio Cortes ◽

...

Keyword(s):

Anatomical Study ◽

Middle Cranial Fossa ◽

Gasserian Ganglion ◽

Anatomical Landmarks ◽

Basal Turn ◽

Caucasian Race ◽

Iatrogenic Damage ◽

Anterior Petrosectomy ◽

Cranial Fossa ◽

Hearing Damage

Abstract Objective The Kawase approach provides access to the petroclival and posterior cavernous sinus regions, cerebellopontine angle, and upper basilar artery territory. Nevertheless, it remains one of the most challenging approach for neurosurgeons, due to the considerable related morbidity and mortality. The goal of this study was to evaluate the relationship between anatomical landmarks and their possible variations, and to measure the extension of the Kawase space, to define the reliability of these landmarks while performing an anterior petrosectomy. Design Using eight cadaveric specimens (15 sides), an anatomical dissections and extradural exposure of the Kawase area were performed. Settings A two-step analysis of the distances between the mandibular branch of the trigeminal nerve (V3) and the structures at risk of iatrogenic damage was performed. Main outcome measures We measured the distance between V3 and the basal turn of the cochlea, and between V3 and the internal acoustic canal (IAC), analyzing the limits of bone resection without causing hearing damage. Results We analyzed eight cadaveric (15 sides) formalin-fixed heads injected with colored silicone: four males and four females of Caucasian race (mean age: 73.83 years). We found a mean distance of 10.46 ± 1.13 mm between the great superficial petrous nerve (GSPN) intersection with V3 and the basal turn of the cochlea, and of 11.92 ± 1.71 mm between the origin point of V3 from the Gasserian ganglion and the fundus of the IAC. Conclusion The knowledge of the safe distance between the most applicable anatomic landmarks and the hearing structures is a practical and useful method to perform this approach reducing related comorbidity.

Download Full-text

Transorbital endoscopic approaches to the skull base: a systematic literature review and anatomical description

Neurosurgical Review ◽

10.1007/s10143-020-01470-5 ◽

2021 ◽

Author(s):

Alperen Vural ◽

Andrea Luigi Camillo Carobbio ◽

Marco Ferrari ◽

Vittorio Rampinelli ◽

Alberto Schreiber ◽

...

Keyword(s):

Systematic Review ◽

Skull Base ◽

Current Literature ◽

Anatomical Study ◽

Pooled Analysis ◽

Surgical Anatomy ◽

Anatomical Landmarks ◽

Endoscopic Transorbital ◽

Ventral Skull Base

AbstractTransorbital endoscopic approaches are increasing in popularity as they provide corridors to reach various areas of the ventral skull base through the orbit. They can be used either alone or in combination with different approaches when dealing with the pathologies of the skull base. The objective of the current study is to evaluate the surgical anatomy of transorbital endoscopic approaches by cadaver dissections as well as providing objective clinical data on their actual employment and morbidity through a systematic review of the current literature. Four cadaveric specimens were dissected, and step-by-step dissection of each endoscopic transorbital approach was performed to identify the main anatomic landmarks and corridors. A systematic review with pooled analysis of the current literature from January 2000 to April 2020 was performed and the related studies were analyzed. Main anatomical landmarks are presented based on the anatomical study and systematic review of the literature. With emphasis on the specific transorbital approach used, indications, surgical technique, and complications are reviewed through the systematic review of 42 studies (19 in vivo and 23 anatomical dissections) including 193 patients. In conclusion, transorbital endoscopic approaches are promising and appear as feasible techniques for the surgical treatment of skull base lesions. Surgical anatomy of transorbital endoscopic approaches can be mastered through knowledge of a number of anatomical landmarks. Based on data available in the literature, transorbital endoscopic approaches represent an important complementary that should be included in the armamentarium of a skull base team.

Download Full-text

Suboccipital Transhorizontal Fissure Approach for Posterior Cranial Fossa Lesions: A Cadaveric Study and First Clinical Experience

Operative Neurosurgery ◽

10.1093/ons/opab345 ◽

2021 ◽

Author(s):

Ryota Tamura ◽

Makoto Katayama ◽

Kohsei Yamamoto ◽

Takashi Horiguchi

Keyword(s):

Fourth Ventricle ◽

Cerebellopontine Angle ◽

Anatomical Study ◽

Posterior Cranial Fossa ◽

Cadaveric Study ◽

Cerebellar Hemisphere ◽

Anatomical Landmarks ◽

Cerebellar Retraction ◽

Cranial Fossa ◽

Wide Access

Abstract BACKGROUND Surgical treatment of pathological lesions in the deep cerebellar hemisphere, cerebellopontine angle (CPA), and fourth ventricle of the posterior cranial fossa (PCF) is challenging. Conventional neurosurgical approaches to these lesions are associated with risk of various complications. Mastery of efficient fissure dissection is imperative when approaching deep-seated lesions. The horizontal fissure (HF) is the largest and deepest fissure of the cerebellum. OBJECTIVE To conduct an anatomical study and introduce a novel suboccipital trans-HF (SOTHF) approach to access lesions of the deep cerebellar hemispheres, CPA, and upper fourth ventricle of the PCF. METHODS We performed a cadaveric dissection study focusing on anatomical landmarks and surgical feasibility of the SOTHF approach then implemented it in 2 patients with a deep cerebellar hemispheric tumor. RESULTS Anatomical feasibility of the SOTHF approach was demonstrated and compared with conventional approaches in the cadaveric study. Opening the suboccipital surface of the HF to create medial, intermediate, and lateral surgical corridors provided optimal viewing angles and wide access to the deep cerebellar hemispheres, CPA, and upper fourth ventricle without heavy cerebellar retraction. Sacrificing cerebellar neural structures and complex skull base techniques were not required to obtain adequate exposure. The SOTHF approach was successfully applied without complication in 2 patients with a deep cerebellar hemispheric tumor. CONCLUSION The HF is an important cerebellar fissure that provides a gateway to deep areas of the PCF. Further studies are needed to define and expand applications of the SOTHF approach.

Download Full-text