CT-anatomy of the nasolacrimal sac and duct

Morphometric and morphological evaluation of the nasolacrimal groove in 150 dry bones in the Anatolian population

PUPOSE

In this study, we aimed to evaluate the anatomical features of the nasolacrimal groove in detail by providing a morphological classification based on morphometric evaluations of the nasolacrimal groove.

METHODS

A total of 150 sagittal dry bones in the Department of Anatomy, Faculty of Medicine, Istanbul University were evaluated. The length and the width at different points of the nasolacrimal canal were calculated. According to the widths of the nasolacrimal canal ten different morphological types were revealed.

RESULTS

The length of the canal was found as mean 13.62 ± 2.42 mm on the right and 12.44 ± 2.68 mm on the left side. The entrance, the base, the upper and the lower thirds of nasolacrimal canal were 6.22 ± 1.19 mm, 7.95 ± 1.85 mm, 5.85 ± 1.06 mm, 6.60 ± 1.54 mm, on the right and 6.08 ± 1.16 mm, 7.24 ± 1.64 mm, 5.45 ± 1.29 mm, 6.23 ± 1.48 mm, on the left side, respectively. The width of the entrance of the nasolacrimal canal was the narrowest width compared to the base, upper and lower thirds in 7/10 types of 71/150 cranial bones.

CONCLUSION

This comprehensive morphological classification of the nasolacrimal groove sheds new light on its complex variations. We support that the finding of this study has the potential to improve the precision of diagnostic assessments and guide specific therapeutic interventions for patients with lacrimal drainage disorders.

Inflammation and Dry Eye-like Symptoms as Concomitant Manifestations of Laryngo-Pharyngeal Reflux

PURPOSE

Laryngo-pharyngeal reflux (LPR) is a common worldwide disease. LPR symptoms may involve distant organs and tissues including the ocular surface with manifestations of a Dry Eye-like disease. We evaluated the concomitant involvement of the ocular surface in patients with LPR. We also defined the clinical signs and the roles of chemical and neuro-inflammatory mediators in the tears of LPR patients.

METHODS

Seventy-seven patients with LPR (mean age 65.8 ± 16.8 SD) and 25 healthy controls (mean age 56.5 ± 16.3 SD) were recruited from the otorhinolaryngology unit. Each subject was evaluated for the presence of concomitant ocular surface disease through clinical examination, including the measurement of tear break-up time (TBUT) and the Ocular Surface Disease Index (OSDI) questionnaire. Tears and conjunctival imprints were collected. The presence of pepsin in tears was detected by ELISA. HLA-DR in conjunctival imprints were imaged by immunofluorescence microscopy. RT-PCR quantified conjunctival mRNA transcripts of HLA-DR, IL-8, MUC5AC, NADPH, VIP, and NPY.

RESULTS

Patients with LPR had significantly increased OSDI and reduced TBUT scores compared to control subjects (p < 0.05 each). Pepsin was detected in 51% of patient tears while it was not measurable in the controls (p < 0.01). Immunoreactivity for HLA-DR in the conjunctival impressions was greater than for the controls with an increased mRNA expression (p < 0.05). mRNA transcripts for IL-8, NADPH, and VIP were significantly increased in LPR patients (p < 0.05 each), but neither MUC5AC nor NPY were different from controls.

CONCLUSIONS

LPR can adversely affect the ocular surface, leading to moderate signs and symptoms of dry eye. This study provides evidence that the presence of pepsin, HLA-DR immunoreactivity, and increased mRNA expression of neuro-inflammatory markers in the tears and conjunctival imprints of LPR patients suggests a potential link between LPR inflammation and ocular surface disease.

Bony nasolacrimal duct size and outcomes of nasolacrimal silicone intubation for incomplete primary acquired nasolacrimal duct obstruction

Purpose

To investigate the association between the bony nasolacrimal duct (NLD) size and outcomes of nasolacrimal silicone intubation for incomplete primary acquired nasolacrimal duct obstruction (PANDO).

Methods

Patients who underwent silicone intubation for incomplete PANDO and had undergone facial computed tomography (CT) were included. Surgical success was judged by both epiphora improvement and normalized tear meniscus height (TMH; < 300 μm) on anterior segment optical coherence tomography at 3 months after tube removal. The area, major axis diameter, and minor axis diameter of the elliptic bony NLD sections were measured in 1.0 mm-thick axial CT images. These bony NLD sizes were analyzed for associations with surgical success and TMH normalization.

Results

Eighty-one eyes of 48 patients were investigated. The smallest area and the smallest minor axis diameter were significantly larger in the success group (49 eyes), compared with those in the failure group (median smallest minor axis diameter: 4.7 mm vs. 3.8 mm, P = 0.008, Mann–Whitney U test). There was also a tendency for the TMH normalization rate to significantly increase as the smallest area and the smallest minor axis diameter increased (P = 0.028 and 0.037, respectively, Fisher’s 2 × 4 tests). Under multivariable logistic regression analysis using generalized estimating equation, a larger smallest minor axis diameter was associated with success of the nasolacrimal silicone intubation (odds ratio: 2.481, 95% confidence interval: 1.143–5.384).

Conclusion

Surgical success of the nasolacrimal silicone intubation in incomplete PANDO is associated with a larger smallest minor axis diameter of the bony NLD. This finding will help understand the pathophysiology of surgical failure after nasolacrimal silicone intubation.

Involvement of Laryngopharyngeal Reflux in Ocular Diseases: A State-of-the-Art Review

BACKGROUND

Laryngopharyngeal reflux-associated symptoms embrace a wide variety of head and neck manifestations. Its participation in eye disorders has recently been postulated, and there is currently no consensus in this regard. The aim of this manuscript is to review the role of reflux in the development of ocular signs and symptoms, and its physio-pathological mechanisms.

METHODS

A systematic approach based on the preferred reporting Items for a systematic review and meta-analysis checklist with a modified population, intervention, comparison, and outcome framework was used to structure the review process of studies that evaluated the possible association, with clear diagnostic methods, of laryngopharyngeal reflux and ocular signs and symptoms. Search was conducted in different indexed databases (PubMed/MEDLINE, the Cochrane Library, Scielo and Web of Science) and through the meta-searcher Trip Database with the keywords: reflux, laryngitis, laryngopharyngeal, gastroesophageal, ocular, eye, symptoms, signs, conjunctivitis, keratitis, dacryocystitis, dry eye.

RESULTS

Seven studies met the inclusion criteria, in which the primary acquired nasolacrimal duct obstruction and the ocular surface disease were evaluated. The local increase of eye pepsin concentration (>2.5 ng/mL) may affect ocular surface though its direct proteolytic activity and the local expression of proinflammatory cytokines. The H. Pylori, with a similar mechanism to reach the lacrimonasal duct, would be associated with the release of proinflammatory and vasoactive substances that would lead to a mucosa injury and chronic inflammation. Ocular Surface Disease Index seems to correlate directly with the reflux severity, with cut-off of 41.67 score as predictor for disease.

DISCUSSION

The role of laryngopharyngeal reflux in the development of ocular disorders has not yet been demonstrated and data are limited and heterogeneous. It seems theoretically conceivable that pepsin may reach lachrymal duct area through hypopharyngeal-nasal gaseous reflux events. Future studies using objective testing for diagnosis and pepsin detection into the tear and nasal mucosa are needed in order to explore this potential relationship.

Meet the Lacrimal Sac: Endoscopic Surgeons' Road Map

Knowledge of lateral nasal wall landmarks in relation to lacrimal apparatus is essential for successful endoscopic dacryocystorhinostomy. This descriptive study of right and left sagittally sectioned ten adult cadaver head specimens was done measuring various lateral nasal wall anatomical landmarks including lacrimal apparatus with digital calipers. Maxillary line was identified in 75%, majority overlapping lacrimal sac. Genu of middle turbinate was at or posterior to nasolacrimal duct. Mean distance of superior end of sac was 8.88 mm above axilla, between its anterior edge and axilla was 10.58 mm and its length was 11.72 mm. Considering above measurements, 'Rule of 10' can be applied for nasal mucosal incision. A "Three Tier Approach" to overcome mucosal (nasal), bony (lacrimal and frontal process of maxilla) and mucosal (sac) boundaries exposes lacrimal sac up to its inferior limit ensuring successful endonasal endoscopic dacryocystorhinostomy.

Morphometric differences in normal bony nasolacrimal anatomy: comparison between four ethnic groups

PURPOSE

To compare bony nasolacrimal duct anatomy between ethnic groups.

METHODS

A retrospective observational study of patients of four ethnic groups who had high-resolution CTs between 2004 and 2019 covering the full length of their nasolacrimal ducts in two hospitals in Essex, England. Only normal ducts were included; patients with tearing or radiological abnormalities were excluded. Measurements were taken of the nasolacrimal duct and surrounding anatomy based on measurements found in the existing literature.

RESULTS

More females (n = 114) than males (n = 40) were included. South Asian (Indian subcontinent), Afro-Caribbean and European groups were equivocal demographically (n = 25-29, mean age 40-45); however, the Oriental group was fewer in number (n = 13) and slightly older (mean age 51). South Asian and European ducts had no significant differences. Afro-Caribbean ducts were wider and shorter than European. Afro-Caribbean faces are wider and their noses flatter and wider than European. Oriental ducts were wider and longer than European, but Europeans have taller noses.

CONCLUSION

The results from our Oriental group fits with the published data in Orientals. The bony nasolacrimal duct is greater in calibre (inner diameter) if the patient is of Afro-Caribbean or Oriental origin compared to European or South Asian. Acquired nasolacrimal duct obstruction in Afro-Caribbean or Oriental patients may be more likely due to secondary causes.

Relationship Between Primary Acquired Nasolacrimal Duct Obstruction, Paranasal Abnormalities and Nasal Septal Deviation

OBJECTIVES

This study aimed to investigate the relationship between nasal septal deviation and paranasal abnormalities in the etiology of primary acquired nasolacrimal duct obstruction (PANDO).

METHODS

A total of 37 (8 men, 29 women) patients (48 eyes with PANDO) between the ages 20 and 77 years (mean age, 52.8 ± 13.1 years) were included in the study. In the axial sections of paranasal sinus computed tomography, the transverse diameters at the most upper part and the most distal part of the nasolacrimal canal were separately measured. In addition, the relationships between PANDO and nasal septal deviation, inferior turbinate hypertrophy, agger nasi cells, paradoxical middle turbinate, concha bullosa, and the angle between the bony inferior turbinate and medial wall of the maxillary sinus were investigated.

RESULTS

A statistically significant relationship was found between PANDO and the axial location of septal deviation classification, axial angle of septal deviation classification, paradoxical middle turbinate, angle between the bony inferior turbinate and medial wall of the maxillary sinus and inferior meatus measure.

CONCLUSION

The authors concluded that the location and angle of the nasal septal deviation in the axial plane, width of the angle between the bony inferior turbinate and medial wall of the maxillary sinus, inferior meatus measure, and paradoxical middle turbinate may be effective factors in the etiology of PANDO.

Neuroimaging of Adult Lacrimal Drainage System

The lacrimal drainage system (LDS) pathology is frequently encountered in the ophthalmology setting but is rarely discussed in the radiology literature. This is even truer for adult LDS lesions despite increase utilization of computed tomography and magnetic resonance in imaging for diagnosis of LDS pathology. The purpose of this image rich review is to highlight common adult LDS pathologies and introduce the radiologist to rare disease entities affecting this pathology rich anatomical region with emphasis on imaging findings, clinical presentation, and differential generation.

Surgical anatomy for Asian rhinoplasty: Part II

Surgical anatomy for Asian rhinoplasty Part I reviewed layered anatomy with neurovascular system of the nose. Part II discusses upper two-thirds of nose which consists of nasal bony and cartilaginous structures. Nasal physiology is mentioned briefly since there are several key structures that are important in nasal function. Following Part III will cover lower one-third of nose including in-depth anatomic structures which are important for advanced Asian rhinoplasty.

Investigating the effects of inferior turbinate outfracture on the lacrimal system by evaluating the results of paranasal sinus computed tomography and nasolacrimal irrigation test

OBJECTIVES

This study aims to investigate the effects of inferior turbinate outfracture on the nasolacrimal system and tear flow.

METHODS

Forty-seven patients (26 males, 21 females) between the ages 18 and 52 years (mean age-29.0 ± 9.6 years) were included in the study. Preoperative nasal examinations and paranasal sinus computed tomography of the patients were carried out; the direction, location, nasal septum deviation classification and inferior turbinate hypertrophy size classification were evaluated. Lacrimal irrigation test was performed preoperatively and 14 days postoperatively.

RESULTS

The study included 47 patients who underwent septoplasty and inferior turbinate outfracture. The mean duration of lacrimal irrigation test was 2.9 ± 0.8 s on the right side and 3.0 ± 1.1 s on the left side preoperatively, and 2.1 ± 0.8 s on the right side and 2.2 ± 1.0 s on the left side postoperatively. No significant relationship between direction, location classification, angle nasal septum deviation classification and lacrimal irrigation test duration was found. A significant relationship between size classification of the left inferior turbinate and preoperative lacrimal irrigation test duration was noted (p = 0.030). Moreover, a significant decrease between preoperative and postoperative lacrimal irrigation test duration after inferior turbinate outfracture (p = 0.000) was noted.

CONCLUSION

We concluded that outfracture of the inferior turbinate with septoplasty surgery may benefit the regulation of tear flow. In addition, we concluded that lacrimal irrigation test duration may be effective in determining the patients with subclinical nasolacrimal duct partial obstruction due to inferior turbinate pathologies.

Air spaces neighbouring the infraorbital canal

OBJECTIVE

The infraorbital canal (IOC) courses through the roof of the maxillary sinus (MS). Different grading systems concerning the topography of the IOC have been proposed. Further, it has been suggested that a transantral IOC would be morphologically related to Haller's cells (HCs). However, we hypothesized that this is not necessarily the case. Hence, we aimed to study the anatomical possibilities of the air spaces located medially to the IOC.

MATERIALS AND METHODS

The cone-beam computed tomography (CBCT) files of 40 adult patients were retrospectively evaluated.

RESULTS

The transantral type of IOC was found in 32.5% of patients. The infraorbital recesses of the MS were found medial to the IOC in 20% of patients. As referred to the nasolacrimal canal, these recesses were either prelacrimal (appearing as false isolated air cells) or retrolacrimal (appearing as false HCs). True HCs were found in 10% of patients. They were located medial to the IOC and they drained into the ethmoidal infundibulum (EI), which was distinct from the MS drainage. In 15% of patients, aerated nasolacrimal ducts (NLDs) were found anterior to the EI and medial to the antral angle. They were capable of masquerading either a HC or an infraorbital recess of the MS.

CONCLUSION

Previous classifications of the IOC, which related it to HCs, were reviewed and the evidence was found to be insufficient to assess the HC-related topography of the IOC. Therefore, to achieve the accurate anatomical identification of the air spaces neighbouring the IOC, the infraorbital recesses of the MS, the HCs, and the aerated NLDs should be carefully discriminated within the antero-supero-medial antral angle.

Lacrimal Drainage Obstruction and Gastroesophageal Reflux Disease: A Nationwide Longitudinal Cohort Study

GOALS

This study aimed to evaluate the association between gastroesophageal reflux disease (GERD) and development of lacrimal drainage obstruction (LDO).

BACKGROUND

It has been hypothesized that GERD may contribute toward the development of LDO.

STUDY

This was a retrospective study of Koreans aged 40 to 79 years registered in the Korean National Health Screening Cohort from 2002 to 2013. Incident cases of LDO were identified according to the Korean Classification of Disease. We compared hazard ratios (HRs) for LDO between 22,570 patients with GERD and 112,850 patients without GERD by 1:5 propensity score-matched analysis.

RESULTS

A total of 135,420 patients, representing 1,237,909 person-years, were evaluated. LDO developed in 1998 (8.9%) patients with GERD and 8565 (7.6%) patients without GERD (P<0.001). The incidence of LDO per 1000 person-years in patients with GERD was 9.7 and 8.3 in those without GERD; the age-adjusted and sex-adjusted HR was 1.17 (95% confidence interval, 1.11-1.23). This association between GERD and LDO was more pronounced among younger individuals (HR, 1.20 for patients 40 to 59-y old; HR, 1.12 for patients 60 to 79-y old) and among men (HR, 1.20 for men; HR, 1.14 for women). Patients with GERD had a higher risk of LDO than those without GERD, irrespective of history of proton-pump inhibitor use. In the sensitivity analysis, GERD patients with esophagitis had a higher risk of LDO than those without esophagitis.

CONCLUSIONS

Our findings suggest that GERD is associated with an increased risk of subsequent LDO and that this effect is more pronounced among adults aged 40 to 59-years old and men.

Morphometric Measurements of Bony Nasolacrimal Canal in Children

OBJECTIVE

Morphology and dimensions of the bony nasolacrimal canal duct (BNLD) as a key factor in the development of primary acquired nasolacrimal duct obstruction. We aimed to obtain detailed morphometric analysis of BNLD in children without nasolacrimal duct pathology by using computed tomography and provide standard measurements by means of age which could be utilized in planning management or in invasive interventions.

METHODS

Picture Archiving Communication Systems database of our hospital's radiology department was searched for this retrospective study. Subjects were under 18 years of age who had undergone a paranasal, maxillofacial, or temporal bone high-resolution computed tomography scan in last 2 years with various indications. Those with fractures including facial bones and/or nasolacrimal canal or history of nasolacrimal duct pathology were excluded from the study. We measured the diameter, angle, and surface area of BNLD.

RESULTS

A total number of 136 subjects (86 boys, 50 girls) were included in the study. The average age was 7.3 ± 5.1 years. We documented statistically significantly positive correlation between all measured diameters and ages (P < 0.001), whereas there was a negative association between mean angle and age (P < 0.001). Mean angle is defined as the angle between BNLD and nasal floor. The surface area of BNLD was found to be significantly increasing depending on age (P < 0.001). However, we could not find any significant association between gender and measured parameters (P > 0.050).

CONCLUSION

Our study demonstrated that development of BNLD continues during childhood, regardless of gender.

Examination of Nasolacrimal Duct Morphometry Using Cone Beam Computed Tomography in Patients With Unilateral Cleft Lip/Palate

OBJECTIVE

The cleft lip/palate (CLP) deformity negatively affects the anatomy of the nasal cavity and maxilla. The effects of this deformity on the lacrimal system have been unidentified yet. This study aimed to evaluate the morphometric changes in the nasolacrimal duct using cone-beam computed tomography (CBCT) in patients with unilateral CLP.

MATERIALS AND METHODS

Retrospective bilateral measurements of the narrowest transversal diameters and the lengths of the nasolacrimal ducts were made for the affected and unaffected sides of 28 patients with CLP and 28 control patients, using the CBCT images. The measurements were statistically compared.

RESULTS

The mean narrowest transversal diameter of the nasolacrimal duct for the affected side of the patients with unilateral CLP was statistically significantly narrower than the unaffected side (P = 0.01). There were no statistically significant differences between the control group and the affected and unaffected sides of patient group with unilateral CLP regarding the nasolacrimal duct diameter. The differences were not statistically significant among all groups regarding the mean nasolacrimal duct length.

CONCLUSION

The diameter of the nasolacrimal duct at the affected side of unilateral CLP was narrower than the unaffected side. According to this result, the CLP deformity can have an effect on the nasolacrimal duct diameter. However, CLP might not affect the nasolacrimal duct length.

Minimally invasive medial maxillectomy and the position of nasolacrimal duct: the CT study

Several minimally invasive modifications of endoscopic medial maxillectomy have been proposed recently, with the least traumatic techniques utilizing the lacrimal recess as a route to enter the sinus. The aim of the study was to analyze the anatomy of medial maxillary wall in the region of nasolacrimal canal and, thus, to determine the capability of performing minimally invasive approach to the maxillary sinus leading through the lacrimal recess. The course of nasolacrimal canal and the distance between the anterior maxillary wall and the nasolacrimal canal (the width of lacrimal recess) were evaluated in 125 randomly selected computed tomography (CT) head examinations. The proportion of cases with unfavorable anatomical conditions (lacrimal recess too narrow to accept a 4 mm optic) to perform minimally invasive middle maxillectomy was assessed. The width of lacrimal recess, measured at the level of the inferior turbinate attachment, varied between 0 and 15.2 mm and was related to slanted course of nasolacrimal canal. The more perpendicular the axis of the canal to the nasal flor, the narrower the lacrimal recess. In about 16% of cases, lacrimal recess width was less than 4 mm and in 14.4% it was missing. The endoscopic approach to maxillary sinus leading through lacrimal recess is possible in about 70% of patients. In the remaining group of patients when the lacrimal recess is too narrow, this type of approach may be difficult to perform without damaging the piriform aperture rim or bony framework of nasolacrimal duct, or it may be impracticable when lacrimal recess is missing.

Nasolacrimal System Aeration on Computed Tomographic Imaging: Sex and Age Variation

PURPOSE

To investigate variation in aeration of the nasolacrimal drainage system between age groups and genders, and to report the reliability of repeated aeration grading and nasolacrimal canal measurements on CT.

METHODS

Retrospective review of CT images from 92 individuals, 60 female and 32 male, was conducted by 3 independent reviewers for the presence of air within the nasolacrimal drainage system. Diameter and area measurements were also obtained at the smallest identifiable portion of the nasolacrimal canal by 2 independent reviewers.

RESULTS

When air is present on CT, it is seen more fully throughout the nasolacrimal system in men as compared to women. Age data demonstrate that patients from the third and fourth decade have significantly more aeration than older patients. Diameter and area of the nasolacrimal duct within the canal at its narrowest point revealed no correlation with sex, age, or nasolacrimal system aeration. Inter-reviewer reliability shows strong repeatability of aeration grading and nasolacrimal duct measurements between multiple reviewers.

CONCLUSIONS

The results suggest CT is reliable and repeatable modality to assess nasolacrimal system aeration and nasolacrimal duct diameter. Decreased aeration of the nasolacrimal system in females and the elderly mirrors epidemiologic trends for those at risk to develop primary acquired nasolacrimal duct obstruction. Variables in nasolacrimal drainage system anatomy, specifically nasolacrimal duct diameter and area, did not vary between sexes or age groups, suggesting aeration may be an overlooked variable in nasolacrimal system function.

Three-Dimensional Reconstruction of the Bony Nasolacrimal Canal by Automated Segmentation of Computed Tomography Images

Objective

To apply a fully automated method to quantify the 3D structure of the bony nasolacrimal canal (NLC) from CT scans whereby the size and main morphometric characteristics of the canal can be determined.

Design

Cross-sectional study.

Subjects

36 eyes of 18 healthy individuals.

Methods

Using software designed to detect the boundaries of the NLC on CT images, 36 NLC reconstructions were prepared. These reconstructions were then used to calculate NLC volume. The NLC axis in each case was determined according to a polygonal model and to 2^nd, 3^rd and 4^th degree polynomials. From these models, NLC sectional areas and length were determined. For each variable, descriptive statistics and normality tests (Kolmogorov-Smirnov and Shapiro-Wilk) were established.

Main Outcome Measures

Time for segmentation, NLC volume, axis, sectional areas and length.

Results

Mean processing time was around 30 seconds for segmenting each canal. All the variables generated were normally distributed. Measurements obtained using the four models polygonal, 2^nd, 3^rd and 4^th degree polynomial, respectively, were: mean canal length 14.74, 14.3, 14.80, and 15.03 mm; mean sectional area 15.15, 11.77, 11.43, and 11.56 mm²; minimum sectional area 8.69, 7.62, 7.40, and 7.19 mm²; and mean depth of minimum sectional area (craniocaudal) 7.85, 7.71, 8.19, and 8.08 mm.

Conclusion

The method proposed automatically reconstructs the NLC on CT scans. Using these reconstructions, morphometric measurements can be calculated from NLC axis estimates based on polygonal and 2^nd, 3^rd and 4^th polynomial models.

Morphometric Evaluation of Bony Nasolacrimal Canal in a Caucasian Population with Primary Acquired Nasolacrimal Duct Obstruction: A Multidetector Computed Tomography Study

Objective

The bony nasolacrimal duct (BNLD) morphology as a contributory factor in primary acquired nasolacrimal duct obstruction (PANDO) is still controversial. The objectives of this study were to evaluate the morphometric differences of BNLDs in unilateral PANDO patients between PANDO and non-PANDO sides, as compared with the control group using multidetector computed tomography (CT).

Materials and Methods

Bilateral BNLDs in 39 unilateral PANDO patients and 36 control subjects were retrospectively reviewed. CT images with 0.5-mm thickness were obtained with a 64-slice scanner. The length, volume, coronal orientation type, sagittal orientation angle of BNLD, and relative lacrimal sac-BNLD angle were assessed. The entrance, minimum and distal end transverse diameters (TD) of BNLD was investigated.

Results

The mean minimum and distal end BNLD TDs measurements were significantly narrower in PANDO patients, both in PANDO and non-PANDO sides, as compared with the control group (p < 0.001 and p = 0.040, respectively); however, there were no significant differences between PANDO and non-PANDO sides within PANDO patients. The length, entrance TD, volume, coronal orientation type, sagittal orientation angle of BNLD, and relative lacrimal sac-BNLD angle were not significantly different between PANDO patients and control subjects, as well as between PANDO and non-PANDO sides within PANDO patients.

Conclusion

The narrow mean minimum and distal end BNLD TD in PANDO patients, in both PANDO and non-PANDO sides, may be associated with PANDO development. The lack of difference between PANDO and non-PANDO sides within PANDO patients and some overlap between PANDO patients and control subjects suggest that narrow BNLD is not the sole factor.

Investigation of pepsin in tears of children with laryngopharyngeal reflux disease

OBJECTIVES

Numerous investigations postulated that laryngopharyngeal reflux (LPR) is implicated in the pathogenesis of various upper airway inflammatory diseases as sinusitis or dacryostenosis. The presence of pepsin in tears might be confirmed the presuntive hypothesis of the arrival in the nasolacrimal ducts and precorneal tears film through the laryngopharyngeal reflux of either gastric acid or stomach secretions (pepsin) with inflammatory potentialities. The aim of this preliminary study was to identify the presence or absence of pepsin in the tears collected from children with a high suspicion of LPR who underwent 24-h pH (MII-pH) monitoring to confirm the disease.

METHODS

This study enrolled 20 patients suffering from symptoms of laryngopharyngeal reflux that underwent 24-h multichannel intraluminal impedance (MII)-pH monitoring to confirm the disease. The findings of the study group were compared with those of a control group of patients with negative pH monitoring. The quantitative analysis of human pepsin concentration in the tear samples was performed by ELISA method in both groups.

RESULTS

Four children (20%) of the study group showed pepsin in the tears. All of the subjects belonging to the control group were negative for its presence. No difference differences in the total number of reflux episodes and the number of weakly basic reflux in the pepsin positive patients vs. pepsin negative children were present.

CONCLUSIONS

20% of the children with diagnosed LPR showed pepsin in the tears. Our specific investigation might provide information regarding sinusitis or dacryostenosis.

Comparison of bony nasolacrimal canal narrowing with or without primary acquired nasolacrimal duct obstruction in a Japanese population

PURPOSE

To compare the minimum diameter of the nasolacrimal canal and its location between patients with or without primary acquired nasolacrimal duct obstruction (NLDO) in a Japanese population.

METHODS

One hundred one patients with unilateral primary acquired NLDO (Group A, 101 affected sides; Group B, 101 unaffected sides) and 50 non-NLDO patients (Group C, 100 sides) were included. Anteroposterior and transverse diameters were measured at the canal entrance and the shortest point using contiguous 1-mm axial computed tomographic images. Canal shapes were classified into 2 types: the "funnel" type (a canal with both minimum diameters at the canal entrance) and the "hourglass" type (a canal with at least one minimum diameter in the canal). The distance from the entrance to the part with the shortest diameter was measured on sides with the hourglass type.

RESULTS

The funnel type was found more frequently in Groups A and B than in Group C (p<0.050), although a difference was not found between Groups A and B (p=0.778). The distance of the transverse diameter was significantly shorter in Groups A and B than Group C (p<0.050), although no significant difference was found in this distance between Groups A and B (p=1.000). There were no significant differences between the groups for each value except for the above mentioned (p>0.050).

CONCLUSIONS

Primary acquired NLDO patients exhibited the funnel type more frequently or there was a shorter distance from the entrance to the part with the shortest diameter than non-NLDO patients, which may enhance the risk of primary acquired NLDO.

Nasolacrimal system aeration on computed tomographic imaging: effects of patient positioning and scan orientation

Purpose

To determine the impact of patient positioning and scan orientation on the appearance of air in the nasolacrimal drainage system on computed tomography (CT) imaging, and the repeatability of the observations.

Methods

This was a retrospective analysis of CT images for 92 patients.

Results

Air was found to be present more fully in the upright-position group as compared with the supine-position group. Comparing axial and coronal scan orientation, no difference in aeration was found, except for the nasolacrimal duct in the upright-position group.

Conclusion

Patient position should be accounted for in diagnostic conclusions and treatment decisions based on CT.

[Comparison of 3T dacryo-MRI by instillation with dacryo-CT scan for evaluation of epiphora]

OBJECTIVES

Epiphora is frequently related to stenosis of the lacrimal drainage pathways. In the evaluation of stenosis, dacryo-CT scan remains the gold standard, despite the need for radiation and catheterization of the lacrimal passages. Evaluation by high field 3T MRI compared to the gold standard in the morphological study of the lacrimal passages and quantification of the stenosis is attractive considering the lack of radiation and non-invasive nature of the technique.

METHODS

Twenty-four patients were included, including 9 with bilateral epiphora, representing 33 pathological drainage systems out of 48. Twenty-three drainage systems underwent subsequent surgery (18 patients, 5 patients bilaterally).

RESULTS

The average diameter on CT scan images of the superior canaliculus was 0.70 mm (± 0.46), of the inferior canaliculus 0.69 (±0.42), the common canaliculus 0.68 (± 0.58), the lacrimal sac 4.32 (± 2.10), and the nasolacrimal duct 1.15 mm (±1.42). 3T dacryo-MRI overestimated the diameters by 0.35 to 1mm (up to 20 % of the lacrimal sac size), and the concordance between dacryo-CT scan and 3T dacryo-MRI was of average value (kappa 0.5, P<0.05) concerning the diagnosis of stenosis. Furthermore, dacryo-CT scan demonstrated higher sensitivity (72.7 %) than 3T dacryo-MRI (42.4 %).

CONCLUSIONS

The two techniques are not equivalent in the diagnosis of stenosis. An optimization of protocols and an evaluation on a larger cohort remain necessary before dacryo-CT scan can be replaced by dacryo-MRI in routine practice.

Diagnostic imaging of the nasolacrimal drainage system. Part I. Radiological anatomy of lacrimal pathways. Physiology of tear secretion and tear outflow

Excessive watering of the eye is a common condition in ophthalmological practice. It may be the result of excessive production of tear fluid or obstruction and insufficiency of efferent tear pathways. The differentiation between obstruction and insufficiency of the lacrimal pathways is still clinically questionable. In the diagnostic process it is necessary to perform clinical tests and additional diagnostic imaging is often needed. Dacryocystography, with or without the extension of the dynamic phase or subtraction option, still remains the criterion standard for diagnostic imaging of the lacrimal obstruction. It may help to clarify the cause and exact place of the obstruction and provide information for further management, especially surgical treatment. Increasingly, new techniques are used in diagnostic imaging of the lacrimal tract, such as computed tomography, magnetic resonance, and isotopic methods. Adequate knowledge of the anatomy and physiology of the lacrimal system and the secretion and outflow of tears is the basis for proper diagnostic imaging. The purpose of this paper is to present the exact anatomy of the lacrimal system, with particular emphasis on the radiological anatomy and the current state of knowledge about the physiology of tear secretion and drainage.

Update on imaging of the lacrimal drainage system

Epiphora is a common problem seen by the ophthalmologist. There are numerous etiologies of a watering eye, and the underlying diagnosis is not always clear. A variety of in-office examination techniques and procedures exist to aid with diagnosis and determination of appropriate therapy, but sometimes the diagnosis remains elusive, or an instituted therapy fails. Lacrimal imaging, particularly in these cases, can be helpful in assessing the function and anatomy of the lacrimal drainage system. This review serves to examine the literature of the last 10 years concerning imaging of the lacrimal drainage system.

Gastroesophageal reflux disease and the presence of pepsin in the tears

The nasolacrimal duct in association with the lacrimal puncta, lacrimal canaliculi and lacrimal sac functions to collect and drain the tear film into the nasal cavity at the inferior nasal meatus where a fold of nasal mucosa, the so-called valve of Hasner, prevents mucous from entering the nose. High-resolution computed tomography demonstrated air inside the sac and nasolacrimal duct in approximately 29.3% of healthy patients suggesting that the system is not completely competent and that air and secretions might reach the precorneal film. Gastroesophageal reflux disease may contribute to dacryostenosis and subsequent primary acquired nasolacrimal duct obstruction. However a cause-effect relationship is unclear and only presumptive unless the presence of pepsin in tears can be demonstrated. Gastroesophageal and extra-esophageal reflux could reach the tear film via the nasolacrimal duct in a retrograde fashion and the middle ear via the Eustachian tube. We postulated that the ascending products of gastroesophageal reflux could cause edema of the nasolacrimal duct mucosa, which might progress to fibrosis and chronic inflammation and, ultimately, complete obstruction of the duct with epiphora. The role of reflux in the initial phase of this pathophysiological mechanisms could be demonstrated indirectly by pepsin. By contrast, the development of dacryostenosis blocking the passage of the nasolacrimal duct and thereby preventing pepsin from reaching the lacrimal film failed to explain the influence of gastroesophageal reflux disease with certainty.

Developmental anatomy of the nasolacrimal duct: implications for congenital obstruction

OBJECTIVE

To measure the height, anteroposterior, and transverse diameters of the nasolacrimal duct (NLD) in normal children between 2 weeks and 34 months of age and to compare the development of the NLD with the maxilla.

DESIGN

Retrospective case series.

PARTICIPANTS

Thirty-eight children with no history of NLD abnormalities who underwent prior axial computed tomography (CT) facial scans of 0.50 to 0.625 mm resolution.

METHODS

Consecutive cases of CT facial series over a 16-month period at a single institution were studied.

MAIN OUTCOME MEASURES

Height, anteroposterior and transverse diameters, and volume of the NLD; height of the maxillary sinus.

RESULTS

The height of the bony NLD increases 1.8-fold, the average diameter increases 1.4-fold, and the volume increases 4.6-fold between 2 weeks and 34 months of age. The dimensional increases of the NLD are nonlinear, with most of the increase occurring in the first 6 months of life. The increase in height of the NLD is highly correlated with postnatal growth of the maxilla.

CONCLUSIONS

Spontaneous resolution of NLD obstruction in normal infants is coincident with elongation, limited radial extension, and the resulting volume expansion of the NLD. We propose that increases in hydrostatic pressure within the fluid column of the NLD combined with central cavitation of the epithelial core can account for the patency of the NLD in normal infants.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Surgical anatomy of the nasolacrimal duct on the lateral nasal wall as revealed by serial dissections

The anatomy of the nasolacrimal duct (NLD) in relation with the lateral nasal wall was studied in 15 half-heads of human adult cadavers by serial photographs of the dissection of the lateral nasal wall. The aim of the study was to determine the intranasal anatomical relationships of the NLD with the lateral nasal wall for surgical reference during endoscopic dacryocystorhinostomy. Following removal of the nasal mucosa anterior to the uncinate process, the exposed bone was removed by drilling. The entire NLD was exposed intranasally. The relationships of the NLD with the maxillary sinus ostium and anterior nasal spine were determined, and the length of the NLD was measured. The morphology of the NLD opening was observed, and its distance from several landmarks were measured. There were three types of intranasal orifice: pin-point, triangular and slit-like. The NLD is located, on average, 24.6 +/- 3.56 mm posterior to the anterior nasal spine. The nearest distances between the opening of the NLD and the nasal floor and between the opening of the NLD and the most anterior attachment of the inferior nasal concha were 13.7 +/- 3.15 and 14.3 +/- 2.05 mm, respectively. The length of the NLD was 21.9 +/- 2.03 mm on average. The nearest distances between the NLD and the maxillary sinus ostium was 3.9 +/- 0.88 mm. Cadaver dissections and the photographs of the fine dissections provide a more accurate description of the lateral nasal wall anatomy. These data provide valuable anatomical information to the surgeon performing endonasal dacryocystorhinostomy.

Morphological and morphometric evaluation of lacrimal groove

The nasolacrimal canal is placed at the anterior part of the inferior lateral wall of the orbit and opens to the inferior nasal meatus. The canal can be obstructed by acquired diseases such as dacryocystitis and posttraumatic epiphora due to nasoorbitoethmoidal fractures. Furthermore in nasolacrimal canal obstructions, dacryocystorhinostomy with balloon dilatation is used frequently. In evaluation of the nasolacrimal canal's acquired diseases, obstruction etiologies and during the reopening of the canal with balloon dilatation, knowing the lacrimal groove's morphology and morphometry play an important role. The aim of the present study was to evaluate not only the morphological features and types but also the morphometric measurements of lacrimal groove. A total of 60 (30 right, 30 left) adult human dry bone maxillae (both male and female samples) from the collection of the Department of Anatomy of Dokuz Eylül University Medical School were used. Digital compass with 0.01 mm sensitivity was used for measurements. Average length of lacrimal groove was 9.62 +/- 2.10 mm. Average width of lacrimal groove was 5.88 +/- 1.53 mm at upper one-third, 8.04 +/- 2.05 mm at middle one-third, and 5.94 +/- 1.28 mm at lower one-third. In 87.7% of cases a crista was observed at the end of the lacrimal groove. Among them, 34.0% were directed to inferior, 54.0% were directed to posterior and 12.0% were horizontal. The present results on the width, length, shape and direction of the lacrimal groove could mediate the etiology of nasolacrimal canal obstructions and could be helpful in surgical approaches and clinical treatment.

Anatomy of the orbit, lacrimal apparatus, and lateral nasal wall

Endoscopic approaches to the orbit take advantage of key anatomic relationships that arise from the fact that the sinonasal tract and orbit are contiguous structures separated by thin bone. For the most part, the orbit is surrounded by air-containing sinuses for much of the length of three of its four borders. Thus, a thorough understanding of both sinonasal and orbital anatomy is essential for safe and efficacious surgery in this complex region. The structural features of the lateral nasal wall and medial orbit are highlighted, and relevant aspects of orbital, lacrimal, and paranasal sinus anatomy are reviewed.

Changes in lumen width of nasolacrimal drainage system after adrenergic and cholinergic stimulation

PURPOSE

To determine the effect of an adrenergic agonist and a cholinergic agonist on the lumen width of the nasolacrimal drainage system.

DESIGN

Prospective, nonrandomized, clinical trial.

METHODS

The asymptomatic sides of 33 patients (23 women, 10 men) with unilateral stenosis/obstruction of the nasolacrimal drainage system were studied. The tear meniscus height of the asymptomatic side was normal, with a patent lacrimal system as revealed by dacryocystography. The nasolacrimal drainage system of the asymptomatic side was infused with 100 microL of 5% phenylephrine hydrochloride (an alpha-1 adrenoceptor agonist) or 100 microL of 2% pilocarpine hydrochloride (a cholinergic agonist), and dacryocystography was performed to determine the lumen width of the nasolacrimal drainage system.

RESULTS

Phenylephrine caused a significant increase of the lumen width of the nasolacrimal drainage system, and the changes were more marked in the nasolacrimal duct (NLD), especially the upper and middle regions, than in the lacrimal sac. In contrast, pilocarpine reduced the lumen width of the NLD significantly, especially in the middle and lower regions, and the lumen width of the lacrimal sac was not significantly changed.

CONCLUSION

The alterations of the lumen width of the nasolacrimal drainage system, especially the lumen width of the NLD by adrenergic and cholinergic agonists, suggest that the lumen width can be changed by the autonomic nervous system.

CT evaluation of nasolacrimal relapse of nasopharyngeal carcinoma

AIM

The aim of the current study was to elucidate the anatomy of the nasolacrimal apparatus using computed tomography (CT), and to investigate the CT findings suggestive of recurrent nasopharyngeal carcinoma (NPC) involving the nasolacrimal apparatus.

MATERIALS AND METHODS

CT images of five patients with clinical or radiological findings suggestive of recurrent NPC who presented with nasolacrimal involvement were reviewed. Involvement of the lacrimal fossa, nasolacrimal canal (NLC), and adjacent anatomic structures including orbit and sinonasal cavities were noted.

RESULTS

CT in all patients demonstrated findings of NLC invasion and ostiomeatal complex obliteration. Four of the five patients showed medial canthal mass or pre-septal thickening, ethmoid bulla opacification and inferior nasal meatal involvement.

CONCLUSION

Knowledge of the anatomy of the nasolacrimal apparatus using CT is critical for evaluating images for tumour recurrence at this site. NLC invasion, a medial canthal mass and pre-septal thickening are important primary indicators for potential involvement of the nasolacrimal apparatus by recurrent NPC. Secondary signs suggesting this distinct form of relapse are obliteration of ostiomeatal channel, ethmoid bulla opacification and inferior nasal meatus involvement.

The presence of a local immune system in the upper blind and lower part of the human nasolacrimal duct

The nasolacrimal duct is exposed to exogenous agents, including potentially harmful microorganisms, coming from the eye surface by the lacrimal sac, and from the nasal cavity by the inferior meatus of the nose. The upper blind and lower part of the human nasolacrimal duct were examined immunohistochemically to ascertain the presence and localization of immunoglobulin-producing cells and the epithelial expression of IgA, IgM, and IgG in order to verify the possible antimicrobial properties of this duct. IgA-, IgM-, and IgG-positive immunocompetent cells were recognizable in the lamina propria of the upper blind and lower part of the human nasolacrimal duct, while an evident immunoreactivity for sIgA, IgM, and IgG was demonstrated in the cytoplasm of the apical epithelial cells. The results suggest that all the effector components of the mucosal immune system are present in that area of the human nasal mucosa next to the opening of the nasolacrimal duct as well as in the human lacrimal sac.