Rhinologic Evaluation in Orbital and Lacrimal Disease





Sinonasal Examination


Examination and palpation of the external nose shows deformities and crepitation and confirms soft-tissue or firm masses. Transillumination of the frontal and maxillary sinuses is an unreliable maneuver. Anterior rhinoscopy can assess the anterior septum and inferior turbinates but rarely provides the entire picture. Tests of olfaction, nasal airflow, or mucociliary flow are rarely indicated in orbital or lacrimal disease. The most important rhinologic examination technique is performed via endoscopy. Endoscopic examination reveals the full range of pathology within the nasal cavity and provides a strong indication of problems within the sinuses as they may relate to the orbit.


Rigid nasal telescopes provide an excellent view of the nasal structures but, depending on the size of the scope, may be difficult to maneuver into certain areas such as the sphenoethmoidal recess. Angled scopes (e.g., 30 degrees, 45 degrees) may help in visualization, or alternatively a flexible nasolaryngoscope may be used. With modern versions of the flexible scope, such as with the camera in the tip of the scope, excellent views of sinonasal anatomy and pathology can be obtained with less discomfort for the patient compared with rigid telescopes.


For endoscopic evaluation, some clinicians use no topical pretreatment. Others prefer some combination of a topical vasoconstrictor and/or local anesthetic. It is helpful to view the mucosa before decongestion to assess swelling and color. Although color and swelling per se are not specific to any disease, the presence of granular, friable mucosa should raise the suspicion of an underlying granulomatous process such as sarcoidosis or granulomatosis with polyangiitis.


After decongestion, a better assessment into the inferior meatus, middle meatus, and sphenoethmoidal recess can be obtained. A systematic approach is advisable so as not to miss anything. Classically three passes with a rigid 30-degree endoscope were described by Stammberger and Wolf, including passes along the nasal floor, middle meatus, and sphenoethmoidal recess. Regardless of which approach is used, the examiner needs to carefully assess the septum, inferior meatus, middle meatus, sphenoethmoidal recess, and the area of the cribriform plate and then repeat the examination on the contralateral side. The nasopharynx, opening of the eustachian tubes, and fossa of Rosenmüller should be assessed.


The region of the middle turbinate is carefully examined identifying the agger nasi (“agger mound”) at the junction of the middle turbinate anteriorly with the lateral wall of the nose. The middle turbinate is assessed for pneumatization (concha bullosa), lateralization, or paradoxical bend. In some patients, the endoscope can be passed between the middle turbinate and septum to visualize the superior turbinate, sphenoethmoidal recess, and opening of the sphenoid sinus.


The examiner is looking for changes in color, swelling, asymmetry, displacement of structures, purulence, polyps, and abnormal fluid. Sometimes palpation of the eye or any external deformity helps to show their connection to intranasal structures by movement intranasally while palpating externally. For sinonasal neoplasms, sensation of branches of the trigeminal nerve should be assessed and extraocular motion and pupillary reflexes should be assessed. The dentition and palate should be assessed for loosening of teeth and abnormal swelling or fullness. The face and neck should be assessed for lymphadenopathy in suspected neoplasia.


The quality and quantity of mucus should be considered. Unilateral watery discharge should raise suspicion of a cerebrospinal fluid leak. Thick tenacious secretions may be associated with an underlying mucociliary problem such as primary ciliary dyskinesia. Discoloration may indicate infection and/or a cellular infiltrate. Thick inspissated secretions may point to allergic fungal rhinosinusitis.


Polypoid changes are commonly seen in the nasal cavity, most often affecting the area of the middle meatus. Typical nasal polyposis is a bilateral disease except in the case of an antrochoanal polyp. The degree of polyposis on both sides is often asymmetric and the polyps are described as smooth, glistening with a “peeled grape” appearance. The size of the polyps can be documented by a variety of grading scales. Unilateral masses of any kind should raise the possibility of a neoplastic process and be considered for biopsy. It is important to consider imaging before any biopsy of a unilateral nasal mass to rule out a connection between the dura and brain, especially in children.


Lacrimal Disease


Anatomy


The anatomy of the lacrimal system is important in understanding rhinologic evaluation. The lacrimal canaliculi and sac lie between the deep and superficial fibers of the orbicularis muscle. The anterior and superficial fibers of the pretarsal orbicularis insert along the anterior lacrimal crest on the frontal process of the maxillary bone and onto the frontal bone. Aberration or loss of structural integrity in any of these structures (e.g., lid laxity, ectropion, or ectropion) can result in symptomatic epiphora.


The lacrimal fossa is made up of the frontal process of the maxillary bone anteriorly and the lacrimal bone posteriorly, forming the anterior and posterior lacrimal crests, respectively. The lacrimal fossa contains the lacrimal sac and occasionally the proximal portion of the nasolacrimal duct. The approximate dimensions of the sac are 14 to 16 mm vertically, 4 to 8 mm anteroposteriorly, and 3 to 5 mm in width. Approximately one-third of the lacrimal sac lies above the level of the medial canthal tendon. The amount of lacrimal sac covered by the bone varies significantly.


The lacrimal sac lies anterior to the anterior tip of the middle turbinate. It then courses posteriorly, inferiorly, and laterally to form the nasolacrimal canal, which terminates in the inferior meatus. The bones that contribute to the canal are the maxillary and lacrimal bones and, in some cases, the inferior turbinate bone. The anterior, posterior, and lateral walls of the canal are usually formed by the maxillary bone. The medial wall is composed of the lacrimal bone superiorly and an extension of the inferior turbinate inferiorly. Significant variation occurs in the width, length, and angulation of the canal, which is often experienced at the time of probing of the nasolacrimal duct.


The length and extent of the nasolacrimal duct vary, ranging from 22 mm in the infant to approximately 35 mm in the adult. There are diverticula and valves in the duct, but the most critical is the valve of Hasner lying in the inferior meatus. The location and patency of this valve varies significantly. The angulation anteroposteriorly and laterally determine the actual point of exit of the duct underneath the inferior turbinate. An abnormally positioned valve of Hasner or a narrow inferior meatus for any reason may impede the flow of tears.


Rhinologic Evaluation


Because of the significant role of the lacrimal gland, the accurate assessment of lacrimal gland diseases is a matter of clinical importance. The endoscope paved the way for the advent of endoscopic transnasal dacryocystorhinostomy in the 1970s and 1980s and became an additional tool in the rhinologic evaluation for diseases of the lacrimal gland. Lacrimal diseases are assessed through inspection and palpation of the eyes, the medial canthus (specifically, the inferior and superior punctum), and the nasolacrimal sac. Inspection focuses on observing periorbital asymmetry and abnormal positioning of eyelids. Common eyelid position abnormalities include entropion and ectropion , inverted and everted eyelids, respectively. Inspection and palpation of the nasolacrimal sac can reveal signs of tumors as well as inflammation of the skin and eye, purulent discharge, or resistance. Although inspection and palpation can provide insight on lacrimal diseases, the first step in diagnosis is the standard nasal endoscopy.


Lacrimal diseases can be diagnosed through nasal endoscopy by placing focus on the maxillary line, the middle and inferior meatus, and the valve of Hasner. The endoscope should be used after decongestion and topical anesthesia. The maxillary line is a curvilinear mucosal projection that is not well defined and is found at the middle to inferior turbinate of the nasal wall. Below the inferior turbinate is the inferior meatus, which can best be reached by orienting the endoscopic toward the posterior end of the inferior turbinate and then rotating the scope along the turbinate into the meatus and following it posteriorly to anteriorly. The valve of Hasner, found within the inferior meatus, can appear in a variety of forms from a true opening in the mucosa to a small indentation of the mucosa only visible on palpation of the sac.


Endoscopy allows for the detection of obstruction and swelling in the nasolacrimal system. Obstruction or swelling can indicate the presence of tumors, mucoceles, polyps, or cysts ( Fig. 6.1 ). Septal deviation, nasal polyps, and tumors should be further evaluated with a full physical examination, including inspection, palpitation, and endoscopy. Obstruction caused by nasal pathology can also be ruled out through endoscopy. It should be noted that dacryocystoceles can sometimes be mistaken for ethmoidal mucoceles owing to their similar appearance as cystic, smooth lesions in the vicinity of the nasolacrimal duct. Further, if the inferior meatus and the valve can be seen with the endoscope, tear consistency can be evaluated by gently palpating the medial canthus. Tears can be analyzed for purulence, sanguineous nature, and viscous characteristics that can indicate and help differentiate between acute infection, tumors, or chronic inflammation. If no tears can be provoked, a stenosis in the system may be present.


Jan 3, 2021 | Posted by in OPHTHALMOLOGY | Comments Off on Rhinologic Evaluation in Orbital and Lacrimal Disease

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