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this product includes access to the online version of this edition for use exclusively by the individual purchaser from the launch of the site This license and access to the online version operates strictly on the basis of a single user per PIN number The sharing of passwords is strictly prohibited, and any attempt to so will invalidate the password Access may not be shared, resold, or otherwise circulated, and will terminate 12 months after publication of the next edition of this product Full details and terms of use are available upon registration, and access will be subject to your acceptance of these terms of use For technical assistance: email online.help@elsevier.com call 800-401-9962 (inside the US) / call +1-314-995-3200 (outside the US) Atlas of CLINICAL GROSS ANATOMY This page intentionally left blank Atlas of CLINICAL GROSS ANATOMY Second Edition Kenneth Prakash Moses, MD Fellow of the Royal Society of Medicine Emergency Room Physician Bear Valley Community Hospital Big Bear Lake, California http://www.MosesMD.com John C Banks, Jr., PhD Associate Professor of Anatomy Department of Pathology and Human Anatomy Loma Linda University School of Medicine Loma Linda, California Pedro B Nava, PhD Professor of Anatomy and Vice-Chair Department of Pathology and Human Anatomy Loma Linda University School of Medicine Loma Linda, California Darrell K Petersen, MBA Instructor Director of Anatomical Services Biomedical Photographer Department of Pathology and Human Anatomy Loma Linda University School of Medicine Loma Linda, California Prosections of the Head, Neck, and Trunk prepared by Martein Moningka Department of Pathology and Human Anatomy Loma Linda University School of Medicine Loma Linda, California 1600 John F Kennedy Blvd Ste 1800 Philadelphia, PA 19103-2899 ATLAS OF CLINICAL GROSS ANATOMY Copyright © 2013, 2005, by Saunders, an imprint of Elsevier Inc Photographs © 2013 by Darrell K Petersen ISBN: 978-0-323-07779-8 All rights reserved No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the Publisher Details on how to seek permission, further information about the Publisher’s permissions policies and our arrangements with organizations such as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website: www.elsevier.com/permissions This book and the individual contributions contained in it are protected under copyright by the Publisher (other than as may be noted herein) Notices Knowledge and best practice in this field are constantly changing As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility With respect to any drug or pharmaceutical products identified, readers are advised to check the most current information provided (i) on procedures featured or (ii) by the manufacturer of each product to be administered, to verify the recommended dose or formula, the method and duration of administration, and contraindications It is the responsibility of practitioners, relying on their own experience and knowledge of their patients, to make diagnoses, to determine dosages and the best treatment for each individual patient, and to take all appropriate safety precautions To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors assume any liability for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions, or ideas contained in the material herein Library of Congress Cataloging-in-Publication Data Atlas of clinical gross anatomy / Kenneth P Moses … [et al.] ; prosections of the head, neck, and trunk prepared by Martein Moningka.—2nd ed    p ; cm   Clinical gross anatomy   Includes index   ISBN 978-0-323-07779-8 (pbk : alk paper)   I.  Moses, Kenneth P.  II.  Title: Clinical gross anatomy   [DNLM:  1.  Anatomy—Atlases QS 17]   611.0022′2—dc23 2012003930 Content Strategy Director: Madelene Hyde Senior Content Development Specialist: Andrew Hall Publishing Services Manager: Patricia Tannian Senior Project Manager: Linda Van Pelt Design Direction: Ellen Zanolle Working together to grow libraries in developing countries Printed in China Last digit is the print number:  9  8  7  6  5  4  3  2  1  www.elsevier.com | www.bookaid.org | www.sabre.org This book is dedicated to the One who has been there to assist and guide me throughout the entire process K P MOSES To my wife Patricia and daughters Erin and Kirsten, for allowing me to spend so many hours in my anatomy lab J C BANKS, JR To the many teachers, professors, and mentors who have had faith in me during my academic career P B NAVA To my mother, for all of her love and support; and to Heather, Jillian, and Megan D K PETERSEN This page intentionally left blank Preface As we completed the manuscript that was to become the first edition of Atlas of Clinical Gross Anatomy, released in 2005, we were pleased with the features of this atlas We were able to produce the original intended objectives, such as outstanding dissections and superb photographs, the general presentation of the sections from the head down to the foot, and the consistent organization within each chapter from superficial structures to deeper structures These all came together nicely The rewards for this endeavor came the next year with our atlas being awarded the R R Hawkins Award from the Professional and Scholarly Division of the Association of American Publishers in February 2006, and then winning the Richard Asher Prize in October 2006, from the Royal Society of Medicine and the Society of Authors As exciting as these accolades were, we readily saw, as an author team and from comments and suggestions we received (especially from our students, who found this volume of great help), several ideas and changes that would greatly improve the usefulness of this atlas in the classroom as well as in the lab Utilizing the time given us and the opportunity to collaborate physically at key moments over the past couple of years, we accomplished several notable changes to produce this second edition of Atlas of Clinical Gross Anatomy We feel that the most significant change in the second edition of our atlas has come in the form of 20 new dissections We completely reworked the chapters on the heart (Chapter 30) and the lungs (Chapter 31) Additionally, the chapter on the vertebral column (Chapter 26) received three new and much-needed dissections featuring ligaments of the vertebral column and the costovertebral joints The remaining new dissections were also within Section 3, with Chapter 33 now including a key dissection of the arteries of the celiac trunk and Chapter 34, the classic presentation of the branches of the abdominal aorta Chapters 36 to 38 on the pelvic girdle and viscera and the perineum were enriched with dissections of the iliac vessels, the female recto-uterine pouch, and the male perineal neurovascular structures A second significant change in this edition is in the titling and labeling of all the dissection images First, each page of topography and dissection received a more accurate title within the color bar at the top of each page, giving the reader a quicker and clearer orientation of the image The descriptive legend below each photograph was revisited for greater clarity Key structures of each image were bolded for emphasis The bolding of key structures helps to illustrate the main components of each dissection We also made a few title changes in the Head and Neck section, which are now more accurate and all-inclusive Finally, another change worth mentioning is the reorganized sequence of Chapters 32 to 35, placing these chapters in a more logical progression In this new edition, we begin with the anterolateral abdominal wall (Chapter 32) and proceed through the abdominal organs (Chapters 33 and 34), ending in Chapter 35 with the posterior abdominal wall It will be apparent to the reader that the major changes are to be found in the Trunk section of this book We feel very pleased with the changes we made to improve the quality of this second edition of Atlas of Clinical Gross Anatomy, and we hope that this book will be useful in your study of human anatomy Kenneth Prakash Moses John C Banks, Jr Pedro B Nava Darrell K Petersen Left to right: Kenneth Prakash Moses, John C Banks, Jr., Pedro B Nava, Darrell K Petersen vii This page intentionally left blank teeth The inferior alveolar nerve terminates in the anterior part of the mandible by branching into the incisive and mental nerves, which carry sensation from the anterior mandibular teeth and the skin around the lower lip and chin Veins and Lymphatics Arteries The maxillary artery is the main vessel to the temporal, infratemporal, and pterygopalatine fossae (Fig 5.3) It is a terminal branch of the external carotid artery and is divided into three regions (mandibular, pterygoid, and pterygopalatine) based on its relationship to the lateral pterygoid muscle: • The mandibular part of the maxillary artery is near the neck of the mandible and branches to form the deep auricular, anterior tympanic, middle meningeal, accessory meningeal, and inferior alveolar arteries • The pterygoid part of the maxillary artery is near the lateral pterygoid muscles and gives rise to the anterior deep temporal, posterior deep temporal, pterygoid, masseteric, and buccal arteries • The pterygopalatine part of the maxillary artery is within the pterygopalatine fossa and branches into the posterior | Parotid, Temporal, and Pterygopalatine Region    Head and Neck superior alveolar, infra-orbital, and descending palatine arteries; the artery of the pterygoid canal; and the pharyngeal and sphenopalatine arteries Venous drainage of the three fossae corresponds to the branches of the maxillary arteries The veins drain to the pterygoid plexus of veins within the infratemporal fossa The pterygoid plexus communicates with the cavernous sinus (a dural venous sinus) It also communicates with the facial vein anteriorly This unique series of interconnections provides a potential route for spread of superficial facial infection to the intracranial cavity Near the TMJ, the maxillary vein joins the superficial temporal vein to form the retromandibular vein The retromandibular vein descends along the lateral aspect of the face and branches into an anterior division, which empties into the facial vein, and a posterior division, which joins the posterior auricular vein to form the external jugular vein Lymphatic drainage of the temporal, infratemporal, and pterygopalatine fossae is to regional lymph nodes—the superficial nodes at the junction of the head and neck and the superior deep cervical nodes along the carotid sheath   Clinical Correlations PAROTID TUMORS Deep auricular artery Anterior tympanic artery Middle meningeal artery Accessory meningeal artery Sphenopalatine artery Infra-orbital artery Descending palatine artery Buccal artery External carotid artery Inferior alveolar artery Masseteric artery Maxillary artery FIGURE 5.3  Branches of the maxillary artery 46 Tumors of the parotid gland are usually well circumscribed, slow growing, and rare They are much more common than tumors of the other major salivary glands (submandibular and sublingual glands) Smoking and increased age are two known risk factors for salivary gland tumors Symptoms of a parotid gland tumor may include tingling on the same side of the face, weakness or paralysis of facial muscles, numbness, trismus (spasm of the muscles that open the jaw), decreased saliva production, a lump or swelling, skin changes, pain, hearing changes, and headaches On examination a mass is usually present In some cases it is mobile, but in advanced cases it is adherent to the underlying tissue or bone Chvostek’s sign—twitching of the facial muscles when the region of the lateral part of the face and parotid gland is tapped—is elicited in patients with hypocalcemia but also occasionally in those with parotid tumors Fine-needle aspiration of the tumor aids in diagnosis by providing cells for histologic analysis A parotid tumor can be further evaluated by computed tomography or magnetic resonance imaging (MRI) Most otolaryngologists (ear, nose, and throat specialists) prefer the sensitivity and detail afforded by MRI In some cases, MRI reveals the presence of tumor spread The standard treatment as well as preferred diagnostic method for both malignant and nonmalignant tumors of the parotid gland is surgical excision Care is taken to preserve the facial nerve [VII], which enters the parotid gland and divides into its terminal branches (temporal, zygomatic, buccal, marginal mandibular, and cervical) Malignant tumors can spread to nearby lymph nodes Parotid and Temporal Region — Surface Anatomy Temporal fossa Zygomatic bone Helix Tragus Parotid gland Masseter muscle Antihelix Nasolabial groove Antitragus Lobule Lower margin of mandible Mental protuberance Angle of mandible Head and Neck  |  Parotid, Temporal, and Pterygopalatine Region Temporomandibular joint Sternocleidomastoid muscle Submandibular gland Thyroid cartilage FIGURE 5.4  Parotid and temporal region—surface anatomy Surface landmarks of the parotid and temporal regions 47 Parotid Region — Parotid Gland and Duct Superficial temporal artery Temporal branches of facial nerve [VII] Parotid, Temporal, and Pterygopalatine Region    Head and Neck Zygomatic branches of facial nerve [VII] Auriculotemporal nerve | Parotid duct Sternocleidomastoid muscle Buccal branches of facial nerve [VII] Great auricular nerve Buccal fat pad Lesser occipital nerve Parotid gland Masseter muscle Platysma muscle Accessory nerve [XI] Superficial part of submandibular gland External jugular vein Cervical branch of facial nerve [VII] Transverse cervical nerve Anterior jugular vein FIGURE 5.5  Parotid region—parotid gland and duct The facial nerve, parotid duct, and external jugular vein are visible as they emerge from the parotid gland 48 Parotid Region — Branches of the Facial Nerve Auriculotemporal nerve Superficial temporal artery and vein Orbicularis oris muscle Zygomatic branch of facial nerve Parotid duct Facial nerve [VII] (cervicofacial division) Sternocleidomastoid muscle Buccal fat pad Posterior auricular vein Parotid gland Retromandibular vein Great auricular nerve Cervical branch of facial nerve External jugular vein Platysma muscle (reflected) Marginal mandibular branch of facial nerve Buccinator muscle Masseter muscle Buccal branch of facial nerve Facial vein Head and Neck  |  Parotid, Temporal, and Pterygopalatine Region Temporal branch of facial nerve Facial artery Thyroid gland Submandibular gland Trachea FIGURE 5.6  Parotid region—branches of the facial nerve Part of the parotid gland has been removed to show the origination of the external jugular vein and the branching structure of the facial nerve [VII] Also observe the close proximity of the parotid gland to the submandibular gland 49 Parotid Region — External Carotid Artery Parotid, Temporal, and Pterygopalatine Region    Head and Neck Auriculotemporal nerve Outline of temporalis muscle | Superficial temporal artery Facial nerve [VII] External carotid artery Sternocleidomastoid muscle Great auricular nerve Maxillary artery Parotid duct Buccal nerve Masseter muscle Stylohyoid muscle Facial vein Lesser occipital nerve Facial artery Marginal mandibular branch of facial nerve [VII] Superficial part of submandibular gland Mandible Anterior belly of digastric muscle FIGURE 5.7  Parotid region—external carotid artery With most of the parotid gland removed, the external carotid artery is visible in the infratemporal fossa 50 Infratemporal Fossa — Maxillary Artery and Proximal Branches Superficial temporal artery Deep temporal artery Masserteric artery Temporal branch of facial nerve [VII] Maxillary artery Articular disc of temporomandibular joint Medial pterygoid muscle Middle meningeal artery Inferior alveolar artery External carotid artery Posterior belly of digastric muscle Lingual nerve Inferior alveolar nerve Posterior superior alveolar artery Buccal nerve Mandibular branch of facial nerve [VII] Masseter muscle (cut) Internal and external carotid arteries Parotid duct (cut) Buccinator muscle Facial vein Head and Neck  |  Parotid, Temporal, and Pterygopalatine Region Auriculotemporal nerve Hypoglossal nerve [XII] Facial artery Submandibular gland Anterior belly of digastric muscle FIGURE 5.8  Infratemporal fossa—maxillary artery and proximal branches This is a continuation of the dissection in Figure 5.7 The right side of the face has been further dissected to show branches of the maxillary artery Small parts of the right eye and right ear are visible 51 Parotid, Temporal, and Pterygopalatine Region Parotid, Temporal, and Pterygopalatine Region    Head and Neck TABLE 5.1  Boundaries of the Temporal, Infratemporal, and Pterygopalatine Fossae Fossa Boundary Components of Boundary Temporal Anterior Processes of frontal and zygomatic bones Superior Temporal lines Inferior Infratemporal crest (zygomatic arch) Anterior Posterior part of maxilla Posterior Tympanic plate of temporal bone Medial Lateral plate of pterygoid process (of sphenoid) Lateral Ramus and coronoid process of mandible Superior Infratemporal surface of greater wing (of sphenoid) Inferior Open to neck (occlusal plane) Anterior Posterior surface of maxilla Posterior Lateral plate of pterygoid process and greater wing (of sphenoid) Medial Perpendicular plate (of palatine bone) Lateral Open through pterygomaxillary fissure | Infratemporal Pterygopalatine TABLE 5.2  Muscles 52 of Mastication Muscle Origin Insertion Action Nerve Supply Blood Supply Temporalis Floor of temporal fossa and temporal fascia Coronoid process and anterior border of ramus of mandible Maintains resting position, elevation, retrusion, and ipsilateral excursion of mandible Mandibular nerve [V3]—deep temporal nerves Superficial temporal and maxillary arteries; middle, anterior, and posterior deep temporal arteries Masseter Zygomatic process of maxilla and inferior aspect of zygomatic arch Lateral aspect of ramus of mandible to angle of mandible Elevation, protrusion, and ipsilateral excursion of mandible Mandibular nerve [V3]—masseter nerve Transverses facial artery; masseteric branch of maxillary and facial arteries Medial pterygoid Medial aspect of lateral plate of pterygoid process of sphenoid, pyramidal process of palatine bone, tuberosity of maxilla Medial aspect of ramus and angle of mandible Protrudes and elevates mandible, deviates to opposite side Mandibular nerve [V3]—nerve to medial pterygoid Facial and maxillary arteries Lateral pterygoid Infratemporal surface of greater wing of sphenoid and lateral surface of lateral plate of pterygoid process of sphenoid Pterygoid fovea, capsule of temporomandibular joint and articular disc Protrudes mandible, pulls disc anteriorly, and deviates to opposite side Mandibular nerve [V3]—muscular branches from anterior division Maxillary artery— muscular branches Infratemporal Fossa — Deep Structures Middle meningeal artery Right eye Superficial temporal artery Auriculotemporal nerve Accessory root of inferior alveolar nerve (from trunk of V3) Lateral pterygoid muscle (cut) Temporomandibular joint Medial pterygoid muscle (cut) Mandible (cut) Facial nerve Lingual nerve Right ear Maxillary artery Buccal nerve Head and Neck  |  Parotid, Temporal, and Pterygopalatine Region Maxillary artery Body of mandible Inferior alveolar nerve and artery entering mandibular canal FIGURE 5.9  Infratemporal fossa—deep structures In this dissection of the infratemporal fossa the superior part of the masseter muscle has been removed to more clearly show the two terminal branches of the external carotid artery—the superficial temporal and maxillary arteries 53 Infratemporal and Pterygopalatine Fossae — Deep Structures Auriculotemporal nerve Sphenoidal sinus Pterygopalatine ganglion Nerve of pterygoid canal Maxillary nerve [V2] Infra-orbital nerve | Parotid, Temporal, and Pterygopalatine Region    Head and Neck Superficial temporal artery Right eye Inferior alveolar artery Lateral pterygoid muscle (cut) Maxillary artery Medial pterygoid muscle Lingual nerve Buccal nerve Parotid duct (cut) Posterior superior alveolar nerve Inferior alveolar nerve FIGURE 5.10  Infratemporal and pterygopalatine fossae—deep structures The right zygomatic arch has been removed to show the maxillary artery and nerve [V2] The sphenoidal sinus is visible at the deepest point in this dissection 54 Pterygopalatine Fossa — Median Sagittal Section Sphenoidal sinus Superior nasal concha Frontal sinus Nasopalatine nerve Middle nasal concha Pituitary gland Anterior arch of CI (atlas) Head and Neck  |  Parotid, Temporal, and Pterygopalatine Region Nasal septum Hard palate Oral cavity Uvula Inferior nasal concha Tongue Vertebral body of CII (axis) Nasopharynx Soft palate FIGURE 5.11  Pterygopalatine fossa—median sagittal section The posterior part of the nasal septum has been removed to show the right sphenoidal sinus, nasopalatine nerve, and inferior nasal concha Observe the close proximity of the pituitary gland to the sphenoidal sinus and nasal cavity 55 Pterygopalatine Fossa — Median Sagittal Section Pterygopalatine ganglion Sphenopalatine artery Maxillary artery Nerve of pterygoid canal Sphenoidal sinus | Parotid, Temporal, and Pterygopalatine Region    Head and Neck Superior nasal concha Inferior nasal concha Greater and lesser palatine nerves Tongue Hard palate Middle nasal concha Pharyngotympanic opening Uvula Soft palate Anterior and posterior arch of CI (atlas) FIGURE 5.12  Pterygopalatine fossa—median sagittal section Posterior parts of the superior and middle nasal conchae have been removed to show the two contents of the pterygopalatine fossa—the sphenopalatine artery and pterygopalatine ganglion 56 Parotid, Temporal, and Pterygopalatine Region — Osteology Parietal bone Frontal bone Pterion Temporal fossa Greater wing (of sphenoid) Orbit Articular tubercle Zygomatic process (of temporal bone) Mandibular fossa Zygomatic bone External acoustic meatus Pterygopalatine fossa Foramen ovale Maxilla Head of mandible Infratemporal fossa Mastoid process Coronoid process Neck of mandible Lateral plate of pterygoid process Head and Neck  |  Parotid, Temporal, and Pterygopalatine Region Squamous part (of temporal bone) Ramus of mandible Mandibular notch Body of mandible Angle of mandible FIGURE 5.13  Parotid, temporal, and pterygopalatine region—osteology Inferior and lateral view of the skull with the mandible moved inferiorly out of the temporomandibular joint to show the temporal, infratemporal, and pterygopalatine fossae The pterygopalatine fossa is deep to the infratemporal fossa 57 Parotid and Temporal Region — Plain Film Radiograph (Lateral View) Frontal process of zygomatic bone Parietal bone Temporal bone Frontal sinus Frontal bone | Parotid, Temporal, and Pterygopalatine Region    Head and Neck Occipital bone Orbit Pinna of ear External auditory meatus CII body Mandibular ramus Mandible Maxilla Maxillary sinus Mandibular condyle FIGURE 5.14  Parotid and temporal region—plain film radiograph (lateral view) Soft tissues, such as the parotid gland located near the region of the mandibular condyle, are not well visualized on plain film radiographs Observe the maxillary sinus and how it is related to the external auditory meatus On a lateral view, the temporal, infratemporal, and pterygopalatine fossae are located between these two landmarks 58 Parotid Region — CT Scan and MRI (Axial Views) Nasal septum Maxillary sinus Mucosal thickening Masseter muscle Medial pterygoid muscle Lateral pterygoid muscle Deep parotid gland Internal carotid artery and internal jugular vein Posterior arch of atlas Ramus of mandible Lateral mass of atlas Spinal cord Semispinalis capitis muscle FIGURE 5.15  Parotid region—CT scan (axial view) The superficial and deep portions of the parotid glands are divided by the retromandibular veins Note the mucosal thickening of the left maxillary sinus because of chronic sinusitis Anterior facial vein Masseter muscle Tongue Buccinator muscle Pharynx Ramus of mandible Parapharyngeal space Internal carotid artery and internal jugular vein Lateral mass of atlas Medial pterygoid muscle Deep and superficial parotid gland Head and Neck  |  Parotid, Temporal, and Pterygopalatine Region Superficial parotid gland Nasopharynx Retromandibular vein Posterior belly of digastric muscle Splenius capitis muscle Spinal cord Semispinalis capitis muscle FIGURE 5.16  Parotid region—MRI (axial view) Observe the relationship between the parotid gland and the masseter muscle Also note that the internal jugular vein and internal carotid artery are located medial to the parotid gland 59 6  Orbit The eye is a complex organ that converts light entering it into a series of electrochemical signals that the brain interprets as a visual picture of the surrounding environment (Fig 6.1) The eye has a tough outer covering, the sclera, that is visible externally as the “white” of the eye In the central portion of the visible eye is the cornea, which is a transparent multilayered membrane through which light enters the eye and where preliminary focusing (primary refraction) occurs Abnormalities in the cornea can therefore decrease visual capacity Deep to the cornea is the anterior chamber of the eye, which contains aqueous humor—a clear fluid through which light passes before entering the pupil The pupil is a circular aperture surrounded by the iris, a contractile pigmented structure that regulates the amount of light entering the eye From the pupil, light passes through the lens, where it is focused, and then through the vitreous humor (a clear, gel-like substance) It finally strikes the retina, from which photosensitive cells send nerve impulses to the brain Lacrimal Apparatus Tears, produced by the lacrimal apparatus, prevent drying of the cornea and conjunctiva, provide lubrication between the eye and eyelid, contain bactericidal enzymes, and improve the optical performance of the cornea They supply oxygen to the avascular cornea The lacrimal apparatus consists of the lacrimal gland and accessory lacrimal glands behind the upper eyelid in the superolateral angle of the orbit and Lens Posterior chamber Optic nerve [II] the lacrimal duct system (Fig 6.2) Tears pass through several ducts and move across the eye in a wave-like pattern created by the upper and lower eyelids during blinking Blinking also aids in removing any foreign material and bacteria On the medial, superior, and inferior lid margins are two openings—the lacrimal puncta These openings collect tears that have crossed the eye and transfer them to the lacrimal sac Tears are then directed into the nasolacrimal duct, which empties into the nasal cavity This connection between the eye and the nasal cavity explains why people often have a runny nose (clear rhinorrhea) when crying Sensory innervation of the lacrimal gland is from the lacrimal nerves, which are branches of the ophthalmic nerve [V1] The facial nerve [VII] provides preganglionic parasympathetic fibers, which enter the pterygopalatine ganglion From there, nerve fibers enter the zygomatic branch of the maxillary nerve [V2] and the lacrimal nerve (of the ophthalmic nerve [V1]) to provide autonomic innervation Lymphatic drainage of the lacrimal gland is to the parotid nodes Bony Orbit Each eye resides within an orbit that is pyramidal in shape; it has an open anterior margin (or base), a posterior apex, a roof, a floor, and medial and lateral walls (Fig 6.3) The medial walls are parallel, whereas the lateral walls diverge from one another at 90° Each orbital wall has several important adjacent relationships: Orbital part (of lacrimal gland) Excretory ducts (of lacrimal gland) Palpebral part (of lacrimal gland) Superior and inferior lacrimal puncta Iris Cornea Lacrimal canaliculi Lacrimal sac Plica semilunaris Anterior chamber Lacrimal caruncle Ciliary body and ciliary muscle 60 Nasolacrimal duct Retina FIGURE 6.1  Section through the eye showing the pathway of light to the retina FIGURE 6.2  Lacrimal apparatus ... Prakash Moses John C Banks, Jr Pedro B Nava Darrell K Petersen Left to right: Kenneth Prakash Moses, John C Banks, Jr., Pedro B Nava, Darrell K Petersen vii This page intentionally left blank... Cataloging-in-Publication Data Atlas of clinical gross anatomy / Kenneth P Moses … [et al.] ; prosections of the head, neck, and trunk prepared by Martein Moningka.? ?2nd ed    p ; cm   Clinical gross anatomy. .. Haines, PhD Professor and Chairman Professor of Neurosurgery Department of Anatomy The University of Mississippi Medical Center Jackson, Mississippi Patricia Collins, PhD Associate Professor