Human Foregut Anatomy, Adjacent Structures, and Their Relation to Surgical Approaches

OBJECTIVEThe lateral recess is a unique structure communicating between the ventricle and cistern, which is exposed when treating lesions involving the fourth ventricle and the brainstem with surgical approaches such as the transcerebellomedullary fissure approach. In this study, the authors examined the microsurgical anatomy around the lateral recess, including the fiber tracts, and analyzed their findings with respect to surgical exposure of the lateral recess and entry into the lower pons.METHODSTen cadaveric heads were examined with microsurgical techniques, and 2 heads were examined with fiber dissection to clarify the anatomy between the lateral recess and adjacent structures. The lateral and medial routes directed to the lateral recess in the transcerebellomedullary fissure approach were demonstrated. A morphometric study was conducted in the 10 cadaveric heads (20 sides).RESULTSThe lateral recess was classified into medullary and cisternal segments. The medial and lateral routes in the transcerebellomedullary fissure approach provided access to approximately 140º–150º of the posteroinferior circumference of the lateral recess. The floccular peduncle ran rostral to the lateral recess, and this region was considered to be a potential safe entry zone to the lower pons. By appropriately selecting either route, medial-to-lateral or lateral-to-medial entry axis is possible, and combining both routes provided wide exposure of the lower pons around the lateral recess.CONCLUSIONSThe medial and lateral routes of the transcerebellomedullary fissure approach provided wide exposure of the lateral recess, and incision around the floccular peduncle is a potential new safe entry zone to the lower pons.

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Pterygopalatine Fossa: Microsurgical Anatomy and its Relevance for Skull Base Surgery

Arquivos Brasileiros de Neurocirurgia Brazilian Neurosurgery ◽

10.1055/s-0040-1718430 ◽

2020 ◽

Author(s):

Gustavo Rassier Isolan ◽

Julio Mocellin Bernardi ◽

João Paulo Mota Telles ◽

Nícollas Nunes Rabelo ◽

Eberval Gadelha Figueiredo

Keyword(s):

Skull Base ◽

The Body ◽

Pterygopalatine Fossa ◽

Surgical Approaches ◽

Maxillary Artery ◽

Microsurgical Anatomy ◽

Extensive Resection ◽

Maxillary Nerve ◽

Adjacent Structures ◽

Surgical Field

Abstract Introduction The purpose of this study was to define the anatomical relationships of the pterygopalatine fossa (PPF) and its operative implications in skull base surgical approaches. Methods Ten cadaveric heads were dissected at the Dianne and M Gazi Yasargil Educational Center MicrosurgicaLaboratory, in Little Rock, AK, USA. The PPF was exposed through an extended dissection with mandible and pterygoid plate removal. Results The PPF has the shape of an inverted cone. Its boundaries are the pterygomaxillary fissure; the maxilla, anteriorly; the medial plate of the pterygoid process, and greater wing of the sphenoid process, posteriorly; the palatine bone, medially; and the body of the sphenoid process, superiorly. Its contents are the maxillary division of the trigeminal nerve and its branches; the pterygopalatine ganglion; the pterygopalatine portion of the maxillary artery (MA) and its branches; and the venous network. Differential diagnosis of PPF masses includes perineural tumoral extension along the maxillary nerve, schwannomas, neurofibromas, angiofibromas, hemangiomas, and ectopic salivary gland tissue. Transmaxillary and transpalatal approaches require extensive resection of bony structures and are narrow in the deeper part of the approach, impairing the surgical vision and maneuverability. Endoscopic surgery solves this problem, bringing the light source to the center of the surgical field, allowing proper visualization of the surgical field, extreme close-ups, and different view angles. Conclusion We provide detailed information on the fossa's boundaries, intercommunications with adjacent structures, anatomy of the maxillary artery, and its variations. It is discussed in the context of clinical affections and surgical approaches of this specific region, including pterygomaxillary disjunction and skull base tumors.

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The Supra/Infra Transtentorial Transfalcine Approach for the Removal of a Falcotentorial Meningioma: 2-Dimensional Video

Operative Neurosurgery ◽

10.1093/ons/opy353 ◽

2018 ◽

Vol 16 (6) ◽

pp. E166-E167

Author(s):

Diego Mendez-Rosito

Keyword(s):

External Ventricular Drainage ◽

Pineal Region ◽

Surgical Approaches ◽

Surgical Removal ◽

Falx Cerebri ◽

Sagittal Sinus ◽

Adjacent Structures ◽

Close Relationship ◽

Dural Attachment ◽

Neurologically Intact

Abstract Falcotentorial meningiomas originate in the junction of the falx cerebri and the tentorium. Due to its anatomic vicinity, these tumors have a close relationship with important neurovascular structures surrounding the pineal region including the deep venous system. Surgical approaches would normally consider posterior midline corridors, but decision between supra or infratentorial access should be considered by the size, anatomic displacement of structures, and the infiltration of the dural attachment. This surgical video1,2 demonstrates the surgical technique and pearls to achieve a stepwise resection of a complex falcotentorial meningioma. We present a case of a 42-yr-old female patient, neurologically intact at presentation. A semi-sitting position was used. Appropriate management of cerebrospinal fluid was obtained with an external ventricular drainage which is kept closed until the dura is opened. A suprainfratentorial craniotomy was done with adequate exposure of the superior sagittal sinus and torcula. The supracerebellar infratentorial corridor was used for inferior internal debulking and arachnoidal dissection of the tumor while the exposure obtained in the posterior interhemispheric allowed a corridor which exposed widely the tumor with transtentorial transfalcine extension. Adequate management of adjacent structures was done while preserving the straight sinus and vein of Galen. A gross total removal of the tumor was achieved and the patient was discharged without complications. After this surgical video, the viewer will have learned the steps to safely achieve a surgical removal of a falcotentorial meningioma taking care of its relationship with the venous and neural adjacent structures.

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Primary Parapharyngeal Space Tumors in a Mexican Cancer Center

Otolaryngology ◽

10.1016/j.otohns.2005.01.013 ◽

2005 ◽

Vol 132 (4) ◽

pp. 587-591 ◽

Cited By ~ 39

Author(s):

Kuauhyama Luna-Ortiz ◽

Jaime Esteban Navarrete-Alemán ◽

Martín Granados-García ◽

Angel Herrera-Gómez

Keyword(s):

Parapharyngeal Space ◽

Tumor Resection ◽

Surgical Approaches ◽

Cancer Center ◽

Peripheral Nerve Sheath Tumors ◽

Parapharyngeal Space Tumors ◽

Adjacent Structures ◽

First Choice ◽

Cervical Approach ◽

Mandibular Swing

OBJECTIVE: To describe clinical and demographic characteristics of the parapharyngeal space tumors and assess surgical approaches used to treat them at our institution. METHODS: A retrospective and descriptive study of the parapharyngeal space tumors, excluding paragangliomas, treated from June 1991 to October 2002 in a cancer center. The study population included 21 patients, 8 men and 13 women, average age of 41 years (range, 20 to 70 years). Fine needle biopsy was done in 5 (24%) patients. Computed tomography (CT) was performed in all patients, and only a few required magnetic resonance image (MRI). RESULTS: Surgical approaches included transcervical alone or in combination with parotidectomy, transoral, or transmandibular (mandibular swing) approach. Laminectomy and segmentary approaches were also performed in 1 patient each. Sixteen (76%) patients had benign lesions and 5 (24%) had malignant tumors. Neurogenic tumors represented 57% of all tumors. Mean tumor size was of 6.7 cm (range, 3 to 11 cm). Six (29%) patients received adjuvant radiotherapy. Complications occurred in 6 (29%) patients, 4 (19%) of which were nervous injuries associated with peripheral nerve sheath tumors. Median disease-free follow-up survival was 33 months (range, 2 to 184 months) despite being an heterogeneous group of histologies. CONCLUSION: Parapharyngeal space is a rare location for head and neck tumors. Cervical approach should be the first choice for large tumors; transoral approach is reserved for tumors less than 3 cm. Conversion to mandibular swing approach when the cervical approach is not offering proper exposure for tumor resection is indicated. Preoperative histologic diagnosis is not required. Nevertheless, CT scan should always be performed in order to exclude paragangliomas, distinguish prestyloid from poststyloid lesions, and to assess the extension of the tumor as well as its relationship with adjacent structures.

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Microsurgical and endoscopic approaches to the pulvinar

Journal of Neurosurgery ◽

10.3171/2016.8.jns16676 ◽

2017 ◽

Vol 127 (3) ◽

pp. 630-645 ◽

Cited By ~ 5

Author(s):

Osamu Akiyama ◽

Ken Matsushima ◽

Abuzer Gungor ◽

Satoshi Matsuo ◽

Dylan J. Goodrich ◽

...

Keyword(s):

Anterior Wall ◽

Surgical Approaches ◽

Superior Parietal Lobule ◽

Surgical Microscope ◽

Adjacent Structures ◽

Microsurgical Techniques ◽

Supracerebellar Infratentorial Approach ◽

Vascular Structures ◽

Formalin Fixed ◽

Different Parts

OBJECTIVEApproaches to the pulvinar remain challenging because of the depth of the target, surrounding critical neural structures, and complicated arterial and venous relationships. The purpose of this study was to compare the surgical approaches to different parts of the pulvinar and to examine the efficacy of the endoscope as an adjunct to the operating microscope in this area.METHODSThe pulvinar was examined in 6 formalin-fixed human cadaveric heads through 5 approaches: 4 above and 1 below the tentorium. Each approach was performed using both the surgical microscope and 0° or 45° rigid endoscopes.RESULTSThe pulvinar has a lateral ventricular and a medial cisternal surface that are separated by the fornix and the choroidal fissure, which wrap around the posterior surface of the pulvinar. The medial cisternal part of the pulvinar can be further divided into upper and lower parts. The superior parietal lobule approach is suitable for lesions in the upper ventricular and cisternal parts. Interhemispheric precuneus and posterior transcallosal approaches are suitable for lesions in the part of the pulvinar forming the anterior wall of the atrium and adjacent cisternal part. The posterior interhemispheric transtentorial approach is suitable for lesions in the lower cisternal part and the supracerebellar infratentorial approach is suitable for lesions in the inferior and medial cisternal parts.The microscope provided satisfactory views of the ventricular and cisternal surfaces of the pulvinar and adjacent neural and vascular structures. The endoscope provided multi-angled and wider views of the pulvinar and adjacent structures.CONCLUSIONSA combination of endoscopic and microsurgical techniques allows optimal exposure of the pulvinar.

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3-D imaging of cells using a confocal laser scanning microscope and digital image processing

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102560 ◽

1988 ◽

Vol 46 ◽

pp. 96-97

Author(s):

Thomas M. Jovin ◽

Michel Robert-Nicoud ◽

Donna J. Arndt-Jovin ◽

Thorsten Schormann

Keyword(s):

Laser Scanning ◽

Confocal Laser Scanning Microscope ◽

Laser Scanning Microscopy ◽

Confocal Laser Scanning ◽

Confocal Laser ◽

Scanning Microscope ◽

Laser Scanning Microscope ◽

Biochemical Processes ◽

Adjacent Structures

Light microscopic techniques for visualizing biomolecules and biochemical processes in situ have become indispensable in studies concerning the structural organization of supramolecular assemblies in cells and of processes during the cell cycle, transformation, differentiation, and development. Confocal laser scanning microscopy offers a number of advantages for the in situ localization and quantitation of fluorescence labeled targets and probes: (i) rejection of interfering signals emanating from out-of-focus and adjacent structures, allowing the “optical sectioning” of the specimen and 3-D reconstruction without time consuming deconvolution; (ii) increased spatial resolution; (iii) electronic control of contrast and magnification; (iv) simultanous imaging of the specimen by optical phenomena based on incident, scattered, emitted, and transmitted light; and (v) simultanous use of different fluorescent probes and types of detectors.We currently use a confocal laser scanning microscope CLSM (Zeiss, Oberkochen) equipped with 3-laser excitation (u.v - visible) and confocal optics in the fluorescence mode, as well as a computer-controlled X-Y-Z scanning stage with 0.1 μ resolution.

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Surgical Approaches to the Brain Stem

Neurosurgery Clinics of North America ◽

10.1016/s1042-3680(18)30570-9 ◽

1993 ◽

Vol 4 (3) ◽

pp. 457-468 ◽

Cited By ~ 16

Author(s):

Dennis Y. Wen ◽

Roberto C. Heros

Keyword(s):

Brain Stem ◽

Surgical Approaches ◽

The Brain

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Current Strategies in the Management of Spinal Metastatic Disease

Swiss Surgery ◽

10.1024/1023-9332.9.2.55 ◽

2003 ◽

Vol 9 (2) ◽

pp. 55-62 ◽

Cited By ~ 7

Author(s):

Bartanusz ◽

Porchet

Keyword(s):

Spinal Cord ◽

Surgical Techniques ◽

Cord Compression ◽

Treatment Modalities ◽

Surgical Approaches ◽

Spinal Stabilization ◽

Management Algorithm ◽

Specific Manner ◽

Extensive Surgery ◽

Selection Of

The treatment of metastatic spinal cord compression is complex. The three treatment modalities that are currently applied (in a histologically non-specific manner) are surgery, radiotherapy and the administration of steroids. The development of new spinal instrumentations and surgical approaches considerably changed the extent of therapeutic options in this field. These new surgical techniques have made it possible to resect these tumours totally, with subsequent vertebral reconstruction and spinal stabilization. In this respect, it is important to clearly identify those patients who can benefit from such an extensive surgery. We present our management algorithm to help select patients for surgery and at the same time identifying those for whom primary non-surgical therapy would be indicated. The retrospective review of surgically treated patients in our department in the last four years reveals a meagre application of conventional guidelines for the selection of the appropriate operative approach in the surgical management of these patients. The reasons for this discrepancy are discussed.

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