Computed Tomography Dacryocystography Research Articles

Multimodal diagnostic imaging and treatment of cheek tooth hypercementosis associated with chronic ocular discharge in a horse

SummaryThis case report discusses the clinical signs, diagnostic findings, treatment and outcome of a 6‐year‐old Italian Warmblood gelding referred for evaluation of a chronic unilateral ocular mucopurulent discharge that had been ongoing for several months. Dacryocystorhinography and computed tomography dacryocystography (CT‐DCG) allowed the identification of a neoformation associated with tooth 206 connected to a cystic lesion occupying the ipsilateral ventral nasal concha. It is likely that both lesions caused stenosis of the nasolacrimal duct and secondary recurrent ocular discharge. Once the 206 tooth had been surgically removed, a histological diagnosis of nodular hypercementosis associated with a small cystic lesion was made. In this case, CT‐DCG was extremely important in identifying the source of the ocular discharge and guiding the surgical planning for tooth removal. A follow‐up telephone conversation with the owner 6 months postoperatively reported that the horse had not shown further ocular discharge.

Bicanalicular silicone intubation versus probing for the treatment of congenital nasolacrimal duct obstruction in children older than 2 years

Background One of the most common conditions presenting to the oculoplastic clinic is congenital nasolacrimal duct obstruction (CNLDO), with an incidence of up to 20% in young children. Early probing as early as 18 months of age is usually associated with very good results. Conversely, the results of probing in older children and the need for intubation, either primary or secondary, are debatable in different studies. Purpose The aim of this study was to compare the outcome of probing versus primary intubation in children older than 2 years having CNLDO. Patients and methods This prospective cohort comparative study was carried out on 40 eyes of 36 children, aged 2–7 years of both sexes, with epiphora due to CNLDO. The eyes were divided into two groups: group A that included 20 eyes that underwent probing, and group B that included 20 eyes that underwent intubation in whom the tube was removed after 3 months. The enrolled children were subjected to local ophthalmological examination, eye lid examination, puncti evaluation, regurge test, nasal evaluation, lacrimal pathway evaluation, and computed tomography dacryocystography before the procedure and 3 months after the procedure. Results The intubation group (group B) was found to have a higher success rate (90%) compared to the probing group (group A) (80%), although the difference was statistically insignificant (P=0.661). On univariate regression analysis, age, contrast volume, and most dilated portion of the lacrimal sac before the procedure were significant predictors for the success rate (P<0.001). In addition, there was a significant relationship between the success rate and age, most dilated portion, and contrast volume after the procedure (P<0.001). Conclusion There was a high success rate for both probing and intubation in older children above 2 years suffering from CNLDO. Although intubation was found to have a higher success rate, the difference was statistically insignificant.

Investigation of lacrimal sac space-occupying lesions using color doppler ultrasound, computed tomography, and computed tomography dacryocystography.

To observe the imaging features of color Doppler ultrasound (CDU) and computed tomography (CT) or computed tomography dacryocystography (CT-DCG) in different types of lacrimal sac space-occupying lesions (SOLs). This retrospective case series study included 21 patients with lacrimal sac SOLs who underwent lacrimal sac surgery between January 2018 and March 2022. The imaging features of CDU and CT or CT-DCG in these patients were extracted from the examination cloud system. The images were observed and analyzed. The detection rate of lacrimal SOLs between CDU (21/21, 100%) and CT or CT-DCG (20/21, 95.2%) had no statistically significant difference (P=1.0). CDU could detect the blood flow signals in all SOLs except mucocele and mucopeptide concretion. Among them, polyps had characteristic imaging changes on CDU and CT-DCG. The mucoceles and mucopeptide concretions had characteristic imaging changes on CDU, which could provide more information for differential diagnosis. The morphology and internal blood flow signals of lacrimal sac SOLs can be observed using CDU. CT or CT-DCG has advantages in observing structural damage around the lacrimal sac mass. Therefore, CDU may be used as a routine examination to exclude lacrimal sac SOLs before dacryocystorhinostomy in the absence of preoperative CT or CT-DCG.

Identification of a novel mutation in the FGF10 gene in a Chinese family with obvious congenital lacrimal duct dysplasia in lacrimo-auriculo-dento-digital syndrome.

To identify the pathogenic gene variant in a family with lacrimo-auriculo-dento-digital syndrome [LADD (MIM 149730)] showing congenital lacrimal duct dysplasia as the main clinical manifestation and lay the foundation for future research on the pathogenic gene. Ophthalmological examinations, including slit-lamp biomicroscopy and lacrimal duct probing, and computed tomography dacryocystography (CT-DCG) were performed for all participants. The family pedigree was drawn, genetic features were analyzed, and the genomic DNA of the subjects was extracted. Pathogenic genes were screened via whole exome sequencing (WES) and confirmed using Sanger sequencing. Six patients belonged to this three-generation family, and their clinical manifestations included congenital nasolacrimal duct obstruction, congenital absence of lacrimal puncta and canaliculi, lacrimal fistulae, and limb deformities. This pattern indicates autosomal dominant inheritance. Diagnosis was based on the clinical characteristics of LADD syndrome, which presented in all the patients in this family. A novel frameshift mutation in the FGF10 gene (NM_004465.1), c.234dupC (p.Trp79Leus*15), was identified in all patients via WES. The variant was confirmed by Sanger sequencing and classified as a "pathogenic mutation" according to the American College of Medical Genetics and Genomics (ACMG) variant interpretation guidelines. A novel frameshift mutation in the FGF10 gene is found in all patients. This finding helps this family with LADD syndrome receiving a more accurate clinical diagnosis and genetic counseling by extending the mutation range of the FGF10 gene.

Reference role of middle turbinate axilla in lacrimal sac localization assisted by computed tomographic dacryocystography-reference value of middle turbinate in locating lacrimal sac

BackgroundThe middle turbinate axilla (MTA) has always been used as a stable anatomic landmark for endoscopic surgeons to locate the lacrimal sac on the lateral nasal wall. Yet, little is known about whether the lacrimal sac size will affect the positioning effect of MTA on lacrimal sac. The aim of this study was to investigate the regularity of lacrimal sac size and lacrimal sac localization through the reference position of the MTA on computed tomographic dacryocystography (CT-DCG) images.MethodsA series of 192 endoscopic dacryocystorhinostomy (DCR) surgeries were performed. All the patients had been diagnosed as unilateral nasolacrimal duct obstruction and received CT-DCG examinations. According to the maximum transverse diameter of the lacrimal sac on CT-DCG, the patients were classified into three groups. Measurements were taken on CT-DCG parasagittal images.ResultsThe average distance from the sac superior fundus (SSF) to the MTA was 7.52 mm ± 3.23 mm, and it increased with the increase of the maximum transverse diameter of the sac among groups (p < 0.01). The average distance from the common canaliculus (CC) to the MTA was 3.95 mm ± 2.49 mm. No significant difference was observed among the groups (p = 0.11). The average distance from the CC to the SSF was 3.41 mm ± 1.31 mm, and it increased with the increase of the sac transverse diameter among groups (p < 0.01).ConclusionsThe lacrimal sac can be accurately located on the lateral nasal wall by the reference position of the MTA on CT-DCG images. The distance of the SSF to the MTA and the SSF to the CC is related to the lacrimal sac size. The relative position of the CC to the MTA is relatively stable on CT-DCG images, which make it possible to locate the lacrimal sac of different sizes and the corresponding nasal mucosa incision design in endoscopic DCR.

Endoscopic dacryocystorhinostomy with mucosal anastomosing in chronic dacryocystitis with three categories of ethmoid sinuses.

To evaluate the outcome of endoscopic dacryocystorhinostomy (En-DCR) with mucosal anastomosis in chronic dacryocystitis patients, with various categories of ethmoid sinuses. Between July 2015 and September 2019, 1439 adult patients, representing 1623 affected eyes, presented with chronic dacryocystitis and were scheduled for En-DCR. The categories of ethmoid sinuses were preoperatively determined, using computed tomography-dacryocystography (CT-DCG), and were classified as category 1 (C1), category 2 (C2), and category 3 (C3). No sinuses anterior to the posterior lacrimal crest defined as C1. Sinuses found between the anterior edge of the lacrimal bone and the posterior lacrimal crest defined as C2. Sinuses found anterior to the lacrimal bone suture defined as C3. At the end of surgery, the dacryocyst and nasal mucosa were anastomosed in C1, and the dacryocyst mucosa and anterior ethmoid sinus were anastomosed in C2 and C3 ethmoid sinus patients. The surgical success rate and related complications, in patients with 3 categories of ethmoid cells, were monitored and documented. Postoperative data was obtained for 179 C1 affected eyes, 878 C2 affected eyes, and 432 C3 affected eyes. The overall success rate of En-DCR was 93.0% (1385/1489). Additionally, the success rates were comparable among the different ethmoid categories at 12mo post operation. We demonstrated that the major reason for surgical failure was intranasal ostial closure, due to granulation or scar tissue. En-DCR is a feasible and highly effective primary treatment for chronic dacryocystitis. To ensure surgical success, the surgery protocol must be designed in accordance with the category of ethmoid sinuses present in individual patient.

Evaluation of epiphora by topical contrast-enhanced CT and MR dacryocystography: which one to choose?

Our study aims to compare non-invasive imaging such as topical computed tomography dacryocystography (CTD) and topical magnetic resonance dacryocystography (MRD) in patients with epiphora. To evaluate the practicability of topical contrast media during helical CTD and topical saline during MRD to reveal obstruction in the nasolacrimal drainage system (NLDS). Twenty participants with nasolacrimal duct obstruction were observed for two years. Ten participants underwent CTD and the other 10 participants underwent MRD. Images were analyzed by two radiologists. Participants were also asked about the level of discomfort of the contrast material versus the saline solution. The NLDS was seen on both CTD and MRD. Very good agreement between the two observers (κ value > 0.81) was seen according to the κ statistics. CTD multiplanar and 3D images allowed for precise diagnosis of the point of obstruction whereas, the MRD did not require any contrast material and showed the point of obstruction. Saline was more comfortable for the patients than topical contrast (P < 0.05). Topical CTD and MRD are non-invasive techniques that can visualize the degree and level of obstruction in the NLDS than conventional invasive cannulation dacryocystography. CTD is useful in visualizing the point of obstruction and smaller drainage structures. However, it is a source of ionizing radiation to the lens. The benefit of MRD is that it requires no contrast or radiation; however, it is poor in depicting the bone anatomy and smaller drainage structures. Finally, saline was better tolerated by patients than topical contrast.

Analysis of Lacrimal Duct Morphology from Cone-Beam Computed Tomography Dacryocystography in a Japanese Population.

PurposeThe dacryoendoscope is a practical instrument for the examination and the treatment of lacrimal duct obstruction. Nevertheless, as it is a rigid fiberscope, manipulation of the endoscope is somewhat affected by the patient’s lacrimal duct alignment and the skeletal structure of the face. The morphology and inclination of the lacrimal duct vary among individuals and ethnic groups. We aimed to evaluate the alignment of the lacrimal duct from the perspective of endoscopic maneuverability in a Japanese population.MethodsThis retrospective study analyzed the cone-beam computed tomography dacryocystography (CBCT-DCG) images of 102 patients diagnosed with unilateral primary acquired nasolacrimal duct obstruction (PANDO) at Ehime University Hospital from December 2015 to May 2021. The following parameters of the lacrimal duct on the contralateral side of unilateral PANDO were investigated: (1) angle formed by the superior orbital rim–internal common punctum–nasolacrimal duct opening, (2) angle formed by the lacrimal sac and the nasolacrimal duct, (3) length of the lacrimal sac, and (4) length of the nasolacrimal duct.ResultsMeasurements of the above parameters were (1) 10.2° ± 7.8° (range, −11° to +27°), (2) −6.3° ± 14.1° (range, −43° to +40°), (3) 8.9 ± 2.3 mm (range, 4.3–17.1), and (4) 13.2 ± 2.7 mm (range, 5.7–20.7), respectively. The Shapiro–Wilk test demonstrated that the values of all parameters, except (3), followed a normal distribution (p = 0.55, 0.30, 0.0002, and 0.39, respectively). No significant difference was found between the female and male groups (p > 0.05).ConclusionThis study reported anthropometric analysis data of the morphology of the lacrimal ducts using CBCT-DCG in a Japanese population. In our cohort, the line from the superior orbital rim through the internal common punctum to the nasolacrimal duct opening inclined anteriorly in 92% of the patients.

Lacrimal Duct Obstruction Caused by Nasomaxillary Fracture: A Retrospective Analysis of Consecutive 12 Patients by Computed Tomographic Dacryocystography.

Nasomaxillary fracture is a characteristic mid-facial fracture, and there are no reports showing the fracture damaging the nasolacrimal system (NLS). This report described nasomaxillary fracture cases with NLS damages, which were assessed by computed tomographic dacryocystography (CT-DCG). A retrospective cohort study of nasomaxillary fractures diagnosed by CT was conducted from 2007 to 2015. Twelve patients (mean age: 27.5 years) were found, and their clinical symptoms were as follows: nasal deformity in 10 patients, infra-orbital hypoesthesia in 7, epiphora in 5, and diplopia in one. CT-DCG was performed for 2 patients who complained epiphora, and obstruction was found in 1 patient. All patients underwent open reduction and internal fixation (ORIF), and epiphora in 5 patients was improved. One patient, however, complained epiphora postoperatively, which was supposed to be due to the unsuitable screw insertion. Since nasomaxillary fracture could give NLS obstruction, CT-DCG is useful for diagnosis. Although ORIF is an optimal treatment, attention is needed to avoid the lacrimal canal in screwing on the nasomaxillary buttress.

Helical computed tomographic-dacryocystography in adult pet dwarf rabbits: procedure and normal appearance

Partial or complete nasolacrimal drainage system (NLDS) occlusion is a common clinical concern in rabbits. It can be assumed that computed tomographic-dacryocystography (CTDCG) might be an efficient technique in this indication. In this prospective study, the technique of CT-DCG and the appearance of the NLDS in eight healthy rabbits on CT-DCG images are described. The quality of visualization of bony structures adjacent to the NLDS was good on pre-contrast computed tomographic images. The bony lacrimal canal had a smooth contour, a regular diameter, and its mean dimensions are provided. CT-DCG technique was easy to perform and offered a good visualization of the NLDS including anatomical narrowings and bendings. CT-DCG is a minimally invasive and informative technique for evaluating the NLDS in rabbits. Its diagnostic usefulness in exploring nasolacrimal diseases remains to be specified in this species.

Preliminary report on screening IGSF3 gene mutation in families with congenital absence of lacrimal puncta and canaliculi.

To investigate the variation of IGSF3 gene in three families with congenital absence of lacrimal puncta and canaliculi, and to lay a foundation for further research on the pathogenic gene of congenital lacrimal duct agenesis. The members of the three families were recruited. The ophthalmologic examinations in details, including slit-lamp biomicroscope, intraocular pressure and fundus examination, etc. were carried out. All patients were checked with paracentesis of puncta membrane and lacrimal duct probing, as well as the computed tomography-dacryocystography (CT-DCG). Peripheral blood of 14 participants (3 normal) from three families were collected, 4 mL each, for genomic DNA extraction, and 11 exon fragments of IGSF3 gene were amplified and sequenced by polymerase chain reaction (PCR) to determine whether there were IGSF3 genetic variation. A total of 14 members from three families were screened for 4 synonymous variants: c.930C>T (p.Pro366=), c.1359T>C (p.Ser709=), c.1797G>A (p.Ser855=), c.1539G>A (p.Ser769=), and 6 missense variants: c.1507G>A (p.Gly759Ser), c.1783T>C (p.Trp851Arg), c.1952G>T (p.Ser 907Ile), c.3120C>G (p.Asp1040Glu), c.3123C>G (p.Asp1041Glu), c.3139_3140insGAC (p.Asp1046_Pro1047insAsp), and the latter three were only found in two patients with absence of lacrimal puncta and canaliculi combined with congenital osseous nasolacrimal canal obstruction from the first family. The same IGSF3 gene mutation c.3139_3140insGAC is found in the patients with congenital absence of lacrimal puncta and canaliculi combine with osseous nasolacrimal canal obstruction.

Cone Beam Computerized Tomography Dacryocystography (CBCT DCG) for the Evaluation of Lacrimal Drainage System Dysfunction.

Lacrimal outflow imaging has been limited in clinical practice due to a combination of modality limitations and efficacy of clinical testing. Cone beam computed tomography dacryocystography (CBCT DCG) has certain advantages over other modalities that may enhance clinical utility. This study was intended to understand the relationships between symptoms, syringing and CBCT DCG in a population of patients presenting with tearing. Cross-sectional cohort study of adult patients undergoing both CBCT DCG and clinical probing and irrigation. Concordance analysis between symptoms, clinical examination, and CBCT DCG was performed at baseline and postoperatively in patients who were treated with dacryocystorhinostomy. CBCT DCG findings correlate fairly well with probing/irrigation (Cohen kappa = 0.376). Excluding cases of canalicular obstruction identified by either method, the correlation between CBCT DCG and probing/irrigation was moderately improved (Cohen kappa = 0.488). There was no statistically significant difference in correlation with patient symptoms between CBCT DCG and probing/irrigation (p = 0.877). Fifteen patients (17 lacrimal systems) patients underwent endoscopic dacryocystorhinostomy (DCR) surgery. Ten demonstrated absence of symptoms 90 days postoperatively, 3 endorsed continued tearing and 2 were lost to follow up. All 3 who demonstrated continued tearing, demonstrated canalicular obstruction on CBCT DCG which was not initially detected on probing/irrigation. CBCT DCG correlates moderately well with probing and irrigation, as well as patient symptoms. This technology may assist in identification of functional/anatomic canalicular obstruction.

Use of an image-guided navigation system for routine endonasal endoscopic dacryocystorhinostomy.

This study aimed to evaluate the results of routine endonasal endoscopic dacryocystorhinostomy combined with computed tomography guided navigation in patients with nasolacrimal duct obstruction. This was a retrospective study of all patients with lacrimal drainage obstruction undergoing stereotactic endoscopic dacryocystorhinostomy between 1st January 2016 and 1st April 2018. Computed tomography dacryocystography was used for intra-operative navigation. Patients with a presaccal obstruction site location were excluded from the study. Endoscopic dacryocystorhinostomy with computed tomography guided navigation was successfully performed in all 17 cases without complications. Early post-operative dislocation of the inserted bicanalicular silicone stent occurred in two patients. Two other patients developed post-operative bacterial infection within the lacrimal sac. Otherwise, the silicone tube was removed three months after surgery, and after further follow up of 8 weeks, 94 per cent of the study population reported complete remission of epiphora. The use of computed tomography guidance in routine endoscopic dacryocystorhinostomy enhanced safety for the patient and avoided unnecessary damage of bone and mucosa surrounding the lacrimal drainage system. Therefore, routine endoscopic dacryocystorhinostomy with additional stereotactic guidance by computed tomography navigation can contribute to high success rates with endoscopic dacryocystorhinostomy.

Clinical utility of SPECT/CT and CT-dacryocystography-enhanced dacryoscintigraphy in the imaging of lacrimal drainage system obstruction

PurposeEpiphora is commonly caused by a relative or complete occlusion in the lacrimal drainage system (LDS), principally a nasolacrimal duct obstruction (NLDO). Dacryoscintigraphy (DSG), an extensively assessed imaging technique in diagnosing its abnormalities, can provide only planar images, according to which it needs to be improved. Our aim was to evaluate clinical utility of simultaneous DSG and single-photon emission computed tomography/computed tomography (SPECT/CT) combined with computed tomographic dacryocystography (CT-DCG) in the evaluation of LDS.MethodsDynamic imaging with DSG was performed, and tracer radioactivity was detected by a gamma camera. Successively, SPECT/CT images of the involved region were gained, followed by CT-DCG, during which a contrast medium was syringed into the affected LDS, and finally contrast CT scans were obtained again from the same region.ResultsFifty-seven patients, mean age 54.25 (± 18.26) years all with unilateral NLDO and 32 control subjects, all with patent LDS, mean age 49.88 (± 18.61) years were evaluated in the study. Delayed outflow of tearing eyes was exposed to DSG compared to the fellow and control eyes. The highest value for sensitivity was observed for SPECT/CT, followed by CT-DCG and DSG techniques, while combining DSG with SPECT/CT, DSG with CT-DCG, and SPECT/CT with CT-DCG, the sensitivity increased to 96.49%, 92.98%, and 94.73%, respectively.ConclusionsAlthough DSG is a sensitive nuclear medicine method, it only provides useful clinical data when simultaneously supplemented with SPECT/CT and CT-DCG trials as they jointly can offer valuable information about the localization of an abnormality and verify stenosis or obstruction.

The role of interventional radiology in the treatment of epiphora.

Epiphora is a relatively common ophthalmologic affection representing almost 5% of clinical consultations in ophthalmology and it consists in the complete or partial obstruction of nasolacrimal duct, leading to insufficient drainage of tears. The traditional treatment is represented by surgery namely, external dacryocystorhinostomy (DCR). Despite the high success rate DCR has many disadvantages and limitations since it requires general anesthesia, it may arise in a permanent facial scar and it is often affected by the reobstruction of the anastomotic tract by fibrotic scars and osteogenic activity. Fluoroscopically guided interventional procedures are a therapeutic alternative to surgery for lacrimal duct system obstructions that can consist either in balloon dacryocystoplasty or in nasolacrimal stent placement. In both cases, a pre-operative imaging characterization of the occlusion is needed for a correct treatment planning. In this review, we propose to highlight the role of interventional radiology in the treatment of epiphora and the role of computed tomography dacryocystography (CTD) in depiction and the pre-interventional planning.

Tomographic and anatomical study of the orbit and nasolacrimal duct in capybaras (Hydrochoerus hydrochaeris-Linnaeus, 1766).

The objective of this study was to describe the reference values of cranial measurements of capybaras, correlating the ocular orbit with the nasolacrimal duct. The documentation of its results can contribute to standardizing characteristics of anatomical normality and favouring the correct diagnosis and treatment of changes. The capybara carcasses, maintained by freezing, were distributed in two groups (G) designated GA (n=12) adult animals (A) and GY (n=13) for young animals (Y). All subjects underwent dacryocystography examination by computed tomography (CT) and cranial measurements. Descriptive analyses of cranial and nasolacrimal duct measurements and statistical analysis of the Pearson correlation with the variable weight were performed. In GA, there was no correlation between the nasolacrimal and cranial duct measurements. However, in the GY, a correlation was verified with facial length (r=.6233), facial width (r=.5771), cranial height (r=.6981), cranial length (r=.7116), total right length (r=.7517) and left length (r=.7999). Thus, in the young animals, cranial length measurements were strongly correlated with nasolacrimal duct lengths. However, this biological behaviour was not observed in adults, demonstrating stability in development. The capybara's ocular orbit was found to be circular and incomplete, with developed zygomatic process of the maxilla. CT dacryocystography is indicated to evaluate the nasolacrimal canal pathway in capybaras, emphasizing the importance of normal anatomical study to aid in treating animals affected by diseases.

Comparison of failed and successful dacryocystorhinostomy by using computed tomographic dacryocystography findings.

To compare the spiral computed tomographic dacryocystography (CT-DCG) findings of failed and successful dacryocystorhinostomies (DCR) and to detect the possible causes of failure before reoperation. Eighteen patients with failed and 15 patients with functional DCR were examined by spiral CT-DCG, a combination of contrast dacryocystography and spiral computed tomography. Radiologists, who were blinded to the clinical status of the patients, measured the diameter of the osteotomy window, evaluated its position relative to the lacrimal sac, and documented any abnormal findings around the osteotomy, which may contribute to the failure of DCR. Location of the osteotomy window was inappropriate in 83% (15/18) of unsuccessful cases and in 7% (1/15) of successful cases and the difference was statistically significant (p<0.01). Presence of the ethmoid air cells medial to the ostium was detected to have a significantly higher frequency in the unsuccessful DCR group (78%, 14/18) than in the successful group (20%, 3/15) (p<0.01). The antero-posterior diameter of bony ostium was less than 15 mm in 94% (17/18) of failed DCR cases, but in only 60% (9/15) of successful DCR cases, and the difference was statistically significant (p<0.05). Some additional findings that may contribute to the failure were noted in failed cases. There were ethmoid sinusitis in three, concha bullosa in two, nasal polyposis in two, mass in medial canthus in one, and extensive granulation tissue around the rhinostomy in one of the failed cases. CONSLUSIONS. CT-DCG is a valuable imaging tool to evaluate DCR failures before reoperation. In this series, CT-DCG showed that small size and inappropriate position of osteotomy, and also extension of ethmoid air cells medial to the lacrimal sac, were frequently seen causative factors of DCR failure. (Eur J Ophthalmol 2005; 15: 523-9).

A Study of the impact of Eyelid Opening and Closing on the Volume and Morphology of the Lacrimal Sac

Purpose: To study the impact of eyelid opening and closing on the volume and morphology of the lacrimal sac using computed tomography (CT) dacryocystography. Method: All of the patients underwent CT dacryocystography. After the contrast agents was injected into a patient's lacrimal sac, the orbit was first scanned with the eye open. And then the patient was told to close the eye firmly for a second scan of the orbit. The volume of the lacrimal sac was calculated by the image processing program which came with the CT machine. At the same time, the anteroposterior and transverse diameters of the lacrimal sac at 3 mm and 7 mm from the top of the lacrimal sac were measured. Results: 14 patients (14 eyes) who met the inclusion criteria were collected between December 2015 and January 2016. The average volume of the lacrimal sac obtained from the calculation based on CT dacryocystography was 0.165 ± 0.073 cm2 when the eyelid was open and 0.165 ± 0.076 cm2 when the eyelid was closed, there is no statistical difference. When the eyelid was open or closed, except for the anteroposterior diameter at the upper portion of the lacrimal sac, the differences in the transverse and anteroposterior diameters at the two positions of the lacrimal sac were no statistical difference. Conclusion: When the eyelid is opened or closed, there is no significant change in the lacrimal sac volume or morphology.

Interactive navigation-guided ophthalmic plastic surgery: the utility of 3D CT-DCG-guided dacryolocalization in secondary acquired lacrimal duct obstructions.

AimThe aim of this study was to report the preliminary experience with the techniques and utility of navigation-guided, 3D, computed tomography–dacryocystography (CT-DCG) in the management of secondary acquired lacrimal drainage obstructions.MethodsStereotactic surgeries using CT-DCG as the intraoperative image-guiding tool were performed in 3 patients. One patient had nasolacrimal duct obstruction (NLDO) following a complete maxillectomy for a sinus malignancy, and the other 2 had NLDO following extensive maxillofacial trauma. All patients underwent a 3D CT-DCG. Image-guided dacryolocalization (IGDL) was performed using the intraoperative image-guided StealthStation™ system in the electromagnetic mode. All patients underwent navigation-guided powered endoscopic dacryocystorhinostomy (DCR). The utility of intraoperative dacryocystographic guidance and the ability to localize the lacrimal drainage system in the altered endoscopic anatomical milieu were noted.ResultsIntraoperative geometric localization of the lacrimal sac and the nasolacrimal duct could be easily achieved. Constant orientation of the lacrimal drainage system was possible while navigating in the vicinity of altered endoscopic perilacrimal anatomy. Useful clues with regard to modifications while performing a powered endoscopic DCR could be obtained. Surgeries could be performed with utmost safety and precision, thereby avoiding complications. Detailed preoperative 3D CT-DCG reconstructions with constant intraoperative dacryolocalization were found to be essential for successful outcomes.ConclusionThe 3D CT-DCG-guided navigation procedure is very useful while performing endoscopic DCRs in cases of secondary acquired and complex NLDOs.

Lacrimal sac diverticulum presenting as a lower eyelid mass with a secreting fistula

Lacrimal sac diverticula are outpouchings of the lacrimal sac. Their various clinical symptoms complicate differential diagnosis. Here we report two patients of distinctive type of lacrimal sac diverticula. Each of them presented with a mass inferior to the medial canthus with a secreting fistula. Irrigation demonstrated lacrimal drainage system patency. The orificium fistula was located at lower palpebral conjunctiva. This distinctive type of lacrimal diverticulum had never been reported in the literature as we know. The mass had no apparent connection with lacrimal sac according to the results of computed tomography dacryocystography and B-scan ultrasonography. All patients underwent surgical exploration and mass removal under general anesthesia. The mass was confirmed as lacrimal sac diverticulum by pathological examination.