Intraoperative Transillumination to Determine the Extent of Frontal Sinus in Subcranial Approach to Anterior Skull Base

Background The aim of this study was to introduce preoperative radiographic frontal recess and sinus anatomic measurements to assist in the selection of patients considered for the modified Lothrop procedure. Methods Data were collected from sagittally reconstructed computed tomography (CT) scans of seven cadaver heads. Four anatomic parameters for measurement were defined as follows: (1) thickness of the nasal beak (desirable <10 mm); (2) midsagittal distance from nasal beak to skull base (adding 1 and 2 provides the anterior–posterior (AP) space at the cephalad margin of the frontal recess; desirable, ≥15 mm); (3) accessible dimension (in a parasagittal plane through the frontal ostium; the distance between two lines drawn parallel to the plane of the anterior skull base and perpendicular to the line of the insertion of the nasal endoscope during surgery; the posterior line is drawn at the skull base and the anterior line is drawn at the posterior margin of the nasal beak; the distance between the lines indicates the space available for instrumentation; desirable, >5 mm); (4) AP dimension of each frontal sinus. Results The average and the range of each parameter measured were as follows: (1) nasal beak thickness = 8.0 mm (5.0–10.4 mm); (2) nasal beak–skull base = 7.9 mm (2.5–14.1 mm); (3) accessible dimension, 6.1 mm (0.9–9.6 mm); (4) AP diameter of the frontal sinus, 9.7 mm (5.2–14.1 mm). Four specimens were considered candidates for modified Lothrop and three were not. Conclusion Preoperative radiographic frontal recess and sinus anatomic measurements may assist in the selection of patients considered for the endoscopic modified Lothrop procedure.

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En-bloc Resection of the Anterior Skull Base for Advanced Cancer of the Frontal Sinus

JOURNAL OF JAPAN SOCIETY FOR HEAD AND NECK SURGERY ◽

10.5106/jjshns.4.117 ◽

1994 ◽

Vol 4 (2) ◽

pp. 117-122

Author(s):

Shin-etsu Kamata

Keyword(s):

Skull Base ◽

Advanced Cancer ◽

Frontal Sinus ◽

En Bloc Resection ◽

Bloc Resection ◽

Anterior Skull Base ◽

En Bloc

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Modified one-piece extended transbasal approach for resection of giant anterior skull base sinonasal teratocarcinosarcoma

Neurosurgical FOCUS ◽

10.3171/2012.v4.focus11301 ◽

2012 ◽

Vol 32 (Suppl1) ◽

pp. E4 ◽

Cited By ~ 2

Author(s):

James K. Liu ◽

Jean Anderson Eloy

Keyword(s):

Skull Base ◽

Frontal Sinus ◽

Malignant Tumors ◽

Tumor Resection ◽

Anterior Wall ◽

Anterior Skull Base ◽

Line Of Sight ◽

Inferior Margin ◽

Sinonasal Teratocarcinosarcoma ◽

Brain Retraction

The transbasal approach is considered the workhorse for removing a variety of benign and malignant tumors of the anterior skull base. In some instances, removal of the supraorbital bar in addition to a standard bifrontal craniotomy (extended transbasal approach) allows for additional basal exposure, thereby minimizing brain retraction. In this operative video atlas report, the authors describe and demonstrate a modified one-piece extended transbasal craniotomy that incorporates the anterior wall of the frontal sinus. The inferior margin of the osteotomy is made as low as possible through the anterior wall of the frontal sinus, starting at the nasofrontal suture and extending laterally over both orbital rims by following the contour of the anterior skull base in the coronal orientation. This modification provides an excellent line of sight to the anterior skull base without any obstruction from bone overhang, which obviates the need for any supraorbital rim removal. Removal of a giant anterior skull base sinonasal teratocarcinosarcoma via the modified one-piece extended transbasal approach is demonstrated in this operative video atlas. The authors describe and illustrate the operative nuances and surgical pearls to safely and efficiently perform the approach, tumor resection, and multilayered reconstruction of the cranial base defect. The video can be found here: http://youtu.be/x1lTtfqKIV0.

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Incidence of frontal sinus aplasia in Indian population

International Journal of Otorhinolaryngology and Head and Neck Surgery ◽

10.18203/issn.2454-5929.ijohns20164811 ◽

2016 ◽

Vol 3 (1) ◽

pp. 108 ◽

Cited By ~ 2

Author(s):

Sanu P. Moideen ◽

Khizer Hussain Afroze M. ◽

Mohan M. ◽

Regina M. ◽

Razal M. Sheriff ◽

...

Keyword(s):

Skull Base ◽

Frontal Sinus ◽

Indian Population ◽

Cross Sectional Study ◽

Anterior Skull Base ◽

Normal Anatomy ◽

Cross Sectional ◽

Craniofacial Trauma ◽

Frontal Sinuses ◽

Operating Surgeon

Background: Aplasia or agenesis of frontal sinuses is not uncommon in the literature. Previous studies have shown unilateral aplasia varying from 1-10% and bilateral agenesis of frontal sinus in 3-10% of patients. It is critical for the operating surgeon to be well aware of the normal anatomy and the variations while doing procedures like endoscopic sinus surgeries, cranialisation of frontal sinuses, frontal sinus trephination, and during anterior skull base procedures. The aim of this study is to demonstrate the incidence of anatomic variations of frontal sinus among Indian populations. Methods: We did a cross sectional study on computed tomography (CT) scan of head, nose and paranasal sinuses in 730 patients above the age of 10 years. We excluded pregnant ladies, patients with prior sinus surgeries, sinonasal tumors, nasal polyposis, craniofacial trauma. Results: We observed an incidence of 6.2% of unilateral aplasia of frontal sinus (2.2% in males and 4.0% in females, 3.7% right side and 2.5% left side) and 2.5% of bilateral frontal sinus aplasia (0.95% in males and 1.5% in females). Conclusions: Frequent occurrence of frontal sinus aplasia highlights the need to gain a thorough knowledge of the normal anatomy and its variations in order to navigate safely through the nose during basic endoscopic sinus or anterior skull base surgeries to avoid complications.

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Pneumosinus Dilatans Helping Subcranial Resection in a Patient with Advanced Ethmoid Malignancy

Craniomaxillofacial Trauma & Reconstruction ◽

10.1055/s-0034-1393736 ◽

2015 ◽

Vol 8 (3) ◽

pp. 218-220

Author(s):

Shawn T. Joseph ◽

Krishnakumar Thankappan ◽

Rahul Buggaveeti ◽

Subramania Iyer

Keyword(s):

Skull Base ◽

Surgical Approach ◽

Frontal Sinus ◽

Anterior Skull Base ◽

Intracranial Extension ◽

Skull Base Tumors ◽

Invasive Approach ◽

Pneumosinus Dilatans ◽

Less Invasive Approach ◽

Malignant Lesions

Subcranial approach is a useful procedure in the management of limited anterior skull base tumors. But the posterior and superior visualization may be limited, in ethmoid malignancies with a large intracranial extension. A 55-year-old male patient, a case of an ethmoid malignancy, with a large intracranial component was resected with adequate margins by a subcranial approach. The coincident pneumosinus dilatans helped the surgical resection. This case demonstrates that assessment of pneumatization of the frontal sinus is as important as the size and extent of the tumor, while deciding an anterior skull base surgical approach. Even large malignant lesions may be approached subcranially if the frontal sinus is proportionately large. Pneumosinus dilatans, though rare, can be used to the benefit of the patient in selecting a less invasive approach.

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Radiological characterisation of the anterior skull base and frontal sinus in the sagittal plane

10.26226/morressier.5adde3c4d462b80290b59888 ◽

2018 ◽

Author(s):

Babatunde Oremule

Keyword(s):

Skull Base ◽

Frontal Sinus ◽

Sagittal Plane ◽

Anterior Skull Base

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