Evaluation of dacryocystorhinostomy failure with computed tomography and computed tomographic dacryocystography

Lacrimal Sac Tumors: A Case Series

Objective

The aim of the study was to describe the clinical presentation, management strategies, and outcomes in a case series of primary lacrimal sac tumors.

Methods

This retrospective study was conducted in Sheikh Fajilatunnessa Mujib Eye Hospital and Training Institute, Bangladesh, from July 1 to December 31, 2020, and included all patients who were evaluated, treated, and followed up for at least 6 months from January 2013 to October 2020. One patient developed a recurrence of the adenocarcinoma of the lacrimal sac after 1 year of primary treatment. Patients' demographic data were analyzed and reviewed from published articles on lacrimal sac tumors. We assessed patients clinically, followed by radiological evaluation. We also analyzed the biopsy technique, treatment modality, and recurrence. An oncologist reviewed all patients to prepare a plan for adjuvant treatment.

Results

Ten patients with lacrimal sac tumors were included in this study. Swelling in the medial canthal region was the most common presenting feature (100%), followed by epiphora (60%) and pain (30%). Open biopsy was preferred over fine-needle aspiration biopsy. Incisional biopsy or complete excisional biopsy was performed for all suspected malignancies. Malignant tumors were found in 7 (70%) cases, and benign tumors in 3 (30%) cases. Non-Hodgkin's lymphoma (NHL) (40%) was the most common malignant lacrimal sac tumor. Mucosa-associated lymphoid tissue lymphoma was 75%, and diffuse large B-cell lymphoma was 25% among the cases of NHL. Patients with epithelial malignancy were treated with external beam radiation therapy, while NHL patients were treated with chemotherapy (CHOP regimen). Recurrence was noted in 1 case (10%) of epithelial malignancy after 1 year of treatment.

Conclusion

Successful management of lacrimal sac tumors requires a high index of suspicion, as these are fatal tumors, often misdiagnosed as dacryocystitis. Nonepithelial malignancies are more predominant than epithelial malignancies, and hematolymphoid tumors are most frequent.

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

PURPOSE

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Dacryocystography: From theory to current practice

PURPOSE

To provide a review and an update on dacryocystography (DCG) and its relevance in the current era.

METHODS

The authors performed a PubMed search of all articles published in English on DCG, digital subtraction-DCG (DS-DCG), computed tomographic DCG (CT-DCG) and magnetic resonance-DCG (MR-DCG). Data analyzed include the indications, techniques, interpretations, complication and limitations.

RESULTS

Dacryocystography has been used for illustrating the morphological and functional aspects of the lacrimal drainage system (LDS). Subtraction DCG provides the precise location of the alterations and acceptably delineates stenosis or an obstruction. Transit time for contrast into the nose varies widely across the studies. Low osmolality iodinated contrast media are tolerated well for DS-DCG and CT-DCG. However, normal saline either mixed with lidocaine or alone provided similar image quality as obtained with gadolinium for MR-DCG. CT-DCG provides useful information in complex orbitofacial trauma and lacrimal tumors. MR-DCG allows better 3D visualization of the LDS and dynamic functional evaluation. Sensitivity of CT-DCG and MR-DCG are mostly similar in identifying an LDS obstruction.

CONCLUSION

Various forms of DCGs can provide additional information to evaluate patients with maxillo-facial trauma, functional epiphora, suspected lacrimal sac diverticula, partial nasolacrimal duct obstruction, and lacrimal drainage tumors. Canaliculi and the membranous part of the nasolacrimal duct are not yet visualized in detail and further focused studies with advanced techniques are required.

Comparison of Failed and Successful Dacryocystorhinostomy by Using Computed Tomographic Dacryocystography Findings

Purpose

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.

Methods

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.

Results

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.

Conclusions

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.

Evaluation of lacrimal tear drainage mechanism using dynamic fluoroscopic dacryocystography

PURPOSE

To evaluate the dynamic change of the canaliculus and the lacrimal sac during blinking using fluoroscopic dacryocystography.

METHODS

Sixteen patients presenting with unilateral epiphora were enrolled in the study. Fluoroscopic dacryocystography was performed in both eyes, and sequential images of the lacrimal drainage system were acquired during blinking. On examination of the contralateral asymptomatic side, the length of the lower canaliculus and the width of the superior and inferior portions of the lacrimal sac were measured and compared between eyelid closure and opening.

RESULTS

The length of the lower canaliculus decreased with eyelid closure in 13 of 16 patients, and the change was statistically significant (p = 0.006, Wilcoxon signed rank test). The width of the superior portion of the lacrimal sac increased with eyelid closure (p = 0.033), but the width of the inferior part did not change significantly (p = 0.679).

CONCLUSIONS

With eyelid closure, the canalicular system contracts, and the superior portion of the lacrimal sac dilates; these may be important parts of the active lacrimal pump mechanism. These findings suggested that the canalicular system and the superior portion of the lacrimal sac play key roles in active tear drainage pump.

Sleeve technique to maintain a large mucosal ostium during endoscopic dacryocystorhinostomy

Currently, many surgeons use bicanalicular silicone tubes as a stent to keep the intranasal mucosal ostium patent when they perform endoscopic dacryocystorhinostomy. The authors describe the sleeve technique using bicanalicular silicone tubes. After inserting the bicanalicular silicone tube, a sleeve is passed over it. The sleeve prevents the nasal mucosa from obstructing the intranasal mucosal ostium and enlarges the mucosal ostium. In primary acquired nasolacrimal duct obstruction, the sleeve technique was applied to 61 cases (group 1); the other 75 cases (group 2) were intubated by bicanalicular silicone tube only. The overall success rate was 95.1% in group 1 and 90.7% in group 2 (P = .51), and the average mucosal ostium at 6 months postoperatively was 3.2 ± 1.1 and 1.9 ± 1.0 mm (P = .04), respectively. The authors believe that the sleeve technique has the advantage of maintaining a larger intranasal mucosal ostium.

Transcanalicular-endonasal semiconductor diode laser-assisted revision surgery for failed external dacryocystorhinostomy

PURPOSE

To report the results of transcanalicular-endonasal revision dacryocystorhinostomy (DCR) with a semiconductor diode laser in cases of failed external DCR.

DESIGN

Prospective, nonrandomized, interventional case series.

METHODS

Fifteen cases in 13 patients with failed external DCR underwent transcanalicular-endonasal DCR with a semiconductor diode laser. A functional successful outcome was defined as a patent nasolacrimal drainage system in nasolacrimal irrigation and a resolution of the symptomatic epiphora and/or mucoid discharge.

RESULTS

The patients were followed for a mean postoperative period of 27.3 months (range, nine to 54 months). The mean duration of the surgery was 19.6 minutes. After the initial revision transcanalicular-endonasal DCR surgery, patency to irrigation was obtained in 12 cases (80%), and 15 cases (100%) after a second revision treatment. Three cases required repeated revision surgery, and three other cases were considered to be functional failures in spite of a patent lacrimal system after the final revision surgery. The overall functional success rate was 80% (12 cases) at the final examination (mean, 27.3 months after surgery), and there were no intraoperative and postoperative complications. The presence of a canalicular obstruction or granulation tissue was not significantly related to the success rates of the revision surgery. The length of time between the primary and revision surgery, gender, age, the duration of the first revision surgery, and the timing of stent removal were also not significantly related to the failed cases.

CONCLUSION

Transcanalicular-endonasal DCR is a minimally invasive procedure and is recommended for patients as an alternative procedure for failed external DCR.

Digital subtraction dacryocystography and syringing in the management of epiphora

AIM

To compare the diagnostic information provided by digital subtraction dacryocystography (DCG) and syringing of the nasolacrimal system in patients with epiphora.

METHODS

Twenty-five lacrimal systems of 17 patients, who presented with unilateral or bilateral epiphora and no concurrent ocular or lid abnormality, were prospectively entered into the study. The patients initially underwent syringing by a lacrimal specialist followed by DCG.

RESULTS

Anatomical obstructions were detected in 88% of systems with syringing and in 84% with DCG. The anatomical sites of obstruction varied between the two tests in 20% of lacrimal drainage systems. Additional useful information was provided by DCG in 28% of the cases, including identification of multiple sites of obstruction, the presence of dacryoliths, fistulae, and congenital malpositions of the nasolacrimal sac-duct junction.

CONCLUSION

The two investigations were found to have comparable detection rates for anatomical obstructions. Syringing thus appears to be able to detect the problem in the majority of cases but DCG can help delineate unidentified factors of surgical significance in a selected subgroup of patients.

The role of larger osteotomy in long term success in external dacryocystorhinostomy

AIM

This study aims to investigate whether it is possible to create a critical size bone defect in external dacryocystorhinostomy (DCR), and also at what size a defect can be considered as being critical for a successful surgical outcome.

METHODS

Eighteen patients undergoing 19 external dacryocystorhinostomies, with the creation of wide osteotomies, were enrolled in this retrospective study. A 2 x 2 cm bone defect, which was considered as the critical size, was created. The postoperative structure of the bone gap was evaluated by computed tomography in axial and coronal planes at least two years after surgery. Functional patency of the ostium was confirmed with irrigation and nasal endoscopic examination.

RESULTS

Thirteen female (72.2%) and five male (27.8%) patients underwent DCR. The patients were aged between 18 and 72 years old (mean+/-S.D.: 45.3+/-13.9). The follow-up time was between 24 and 48 months (mean 30.4 months). The areas of the gaps were between 1.21 and 4 cm(2) (mean+/-S.D.: 2.26+/-0.19).

CONCLUSION

The critical size bone defect (2 x 2 cm) might prevent restenosis in long term follow ups.

Figure-of-eight vertical mattress suture technique for anterior flap suspension to overlying tissues in external dacryocystorhinostomy

PURPOSE

To describe figure-of-eight vertical mattress suture technique in external dacryocystorhinostomy for a combined one-step closure of anterior mucosal flaps and overlying wound tissues and to evaluate its effectiveness on surgical outcome.

DESIGN

A prospective, single surgeon, uncontrolled, interventional case series.

METHODS

A total of 112 consecutive lacrimal drainage systems of 106 patients (84 women, 22 men; 100 unilateral, six bilateral) from June 2002 to January 2006 with acquired nasolacrimal duct obstruction without canalicular disease underwent external dacryocystorhinostomy with this modified technique. Relief of epiphora and anatomic patency were defined as success. Operative time and success rate were evaluated and advantages were stressed and compared with our previous reports.

RESULTS

Mean age was 40.1 years (range, 6 to 75). The etiology was idiopathic in 109 patients and traumatic in three cases. Of 112 lacrimal drainage systems, epiphora was the presenting symptom in 88, combined epiphora and recurrent dacryocystitis in 15, and combined epiphora and mucocele in nine cases. Seven lacrimal drainage systems were revision cases. Mean follow-up was 26.3 months (range, 6 to 48). Success rate was 99.1% (111/112) and mean operative time was 38.2 minutes (range, 28 to 69).

CONCLUSIONS

Such a modified suture technique reveals a rapid and simultaneous one-step closure of two different layers that speeds up surgical procedure; simplifies closure process as the knots are tied completely outside the wound, avoiding the disadvantages of suture tying in a small and deep area; eliminates the dead space between anterior flaps and overlying wound tissues; keeps anterior mucosal flap complex away from posterior flaps that prevents collapse back onto the anastomosis and decreases the possibility of mucosal adhesions and, therefore, fibrotic band formation with underlying tissues that may also be useful in cases with small sacs or osseous openings and in revision cases where scarring is a large concern.

Ultrasonic visualization of the effect of blinking on the lacrimal pump mechanism

BACKGROUND

The role of the lacrimal sac (LS) and the medial canthal tendon in the lacrimal pump mechanism is controversial. This study used ultrasonic visualization to analyze this phenomenon.

METHODS

Movements of the LS and the medial canthal tendon during blinking were visualized with sonography. In addition, the maximal profile area of the LS was measured before and after blinking using 15-MHz sonography in 14 individuals with a normal lacrimal drainage system and in six patients with lacrimal duct obstruction.

RESULTS

The upper part of the LS could be located as an echolucent structure between the lacrimal bone and the medial canthal tendon. The medial canthal tendon appeared to compress the LS during lid closure and release the LS during lid opening. The measured profile area of the visible normal LS at the compression time decreased by 50%. The dilated LS of patients with obstruction could also be compressed by the orbital muscle on blinking, but the maximum area decrease was only 15.5%.

CONCLUSION

The findings imply that the lacrimal part of the orbicularis muscle contracts during blinking, with the medial canthal tendon compressing the LS in a cranial direction. Completion of lid closure then compresses both canaliculi and LS, forcing the intrasacral fluid through the drainage system. The expansion of the LS during the opening phase of the blink causes suction, and after opening of the punctal areas the canaliculi and LS vacuum breaks to reload with tear fluid. These findings demonstrate the importance of the orbicularis muscle and the medial canthal tendon for the lacrimal pump mechanism during blinking.

Pathology and Imaging of the Lacrimal Drainage System

The lacrimal drainage apparatus drains tears from the eye. The system is susceptible to a multitude of pathologic findings, including obstruction, infection, inflammation, and neoplasms. The diagnosis of several of these processes is aided by the use of radiologic studies. In conjunction with dacryocystography, cross-sectional modalities, such as CT and MR imaging have improved the ability of diagnostic imaging to characterize the obstructive nature and soft tissue or osseous changes of various disease processes.

Presurgical and postsurgical ultrasound assessment of lacrimal drainage dysfunction

PURPOSE

In addition to the obligatory clinical tests, imaging of the lacrimal drainage system (LDS) is useful in its clinical evaluation. The purpose of this study was to examine the usability and reliability of ultrasonography in the evaluation of the lacrimal drainage system.

DESIGN

Observational cohort study.

METHODS

A prospective study was conducted at a single institution. We performed ultrasound examinations on 17 patients with epiphora before and after surgery, and on 17 asymptomatic volunteers, to visualize and evaluate the anatomic and functional condition or pathologic abnormalities of the LDS.

RESULTS

Echographic evaluation of the LDS was possible in all individuals. Pathologic abnormalities (canaliculitis, diverticulitis, concretion, or dilation of the lacrimal sac, and reduced functionality of the orbicular muscle and/or lacrimal sac pump) could be well demonstrated. In the postsurgical course, functional patency of the dacryocystorhinostomy opening could be verified in all cases.

CONCLUSIONS

Sonography of the LDS appears to represent a reliable diagnostic technique supplementary to clinical tests in the presurgical and postsurgical examination of patients with epiphora. Pathologic abnormalities that may not be apparent in routine x-ray dacryocystography can be demonstrated with ultrasound techniques. Patients also benefit from the avoidance of exposure to ionizing radiation. However, ultrasound is not suitable for imaging the lower part of the lacrimal sac and the lacrimal duct because of the presence of overlying bony structures.

Computed tomography dacryocystography evaluation of the nasolacrimal apparatus

Computed tomography-dacryocystography (CT-DCG) was used to evaluate the nasolacrimal system in four patients (three dogs and one horse) that were admitted for evaluation of chronic epiphora, facial swelling, or facial trauma. The four patients are reviewed and the technique for performing CT-DCG is described. Additionally, the indications for this procedure are discussed. CT-DCG is advantageous because cross-sectional imaging provides superior resolution of the nasolacrimal apparatus and the relatively long, small-diameter, bony nasolacrimal canal in most veterinary patients.

Systematic unciformectomy for a standardized endonasal dacryocystorhinostomy

PURPOSE

To describe a standardized osteotomy method for endonasal dacryocystorhinostomy (en-DCR) and the results obtained.

DESIGN

Prospective nonrandomized, noncomparative, interventional case series study.

PARTICIPANTS

One hundred consecutive adult patients (81 females, 19 males) underwent en-DCR performed by the same team of oculoplastic and rhinologic surgeons.

METHODS

A standardized procedure was used in all cases. This included endoscopic assessment of the surgical site from the nasal aspect, diaphanoscopy of the common canaliculus, and endonasal osteotomy. Anterior unciformectomy was followed by resection of the lacrimal bone and protected drilling of the maxillary bone of the lacrimal fossa to expose the entire medial aspect of the lacrimal sac. The middle turbinate was preserved whenever atraumatic dissection of the nasal mucosa was possible or when it was resected partially before osteotomy.

MAIN OUTCOME MEASURES

Rate of direct localization of the lacrimal fossa, rate of turbinectomy/septoplasty, rate of residual postoperative tearing, rate and nature of complications

RESULTS

Transillumination of the common canaliculus was obtained directly in 94% of cases; transillumination, required the opening of an ethmoidal cell in 2%, partial resection of the middle turbinate in 3%, and unciformectomy in 1%. Access to the surgical site required partial resection of the middle turbinate in 21% of cases, but no septoplasty. Osteotomy was initiated in 90% of cases by cleavage of the anterior insertion of the uncinate process, and in 5% by cleavage of the first, overdeveloped ethmoidal cell. The cleavage opened directly to the medial aspect of the lacrimal fossa in these 95 cases. Osteotomy was achieved by drilling alone in only five cases. Perioperative complications were limited to significant bleeding in six cases. Postoperative complications included one case of resolved frontal sinusitis on day 3, and one case of inferior lid hematoma with emphysema.

CONCLUSIONS

The authors suggest that anterior resection of the uncinate process is the most important surgical step to expose the medial aspect of the lacrimal fossa during endonasal DCR, whereas partial resection of the middle turbinate can be considered optional.

Endoscopic terminal dacryocystorhinostomy

OBJECTIVE

Traditional endoscopic dacryocystorhinostomy (DCR) involves creation of a lacrimal sac side hole that may close down in the presence of a partially patent lower lacrimal drainage system. Endoscopic terminal DCR is a modified DCR procedure designed to prevent this problem.

METHODS

From September 1996 to June 1999, 16 patients (17 sides) had endoscopic terminal DCR that involved resection of the lacrimal sac-duct junction to achieve total separation of the lacrimal sac from the nasolarcrimal duct and creation of a terminal DCR opening.

RESULTS

Ten of the 17 DCRs were primary and 7 were revisions. The follow-up ranged from 3 to 36 months. There were two failures. One failure was due to canalicular obstruction and the other was due to prolapse of orbital fat hindering proper fashioning of the mucosal flap. The overall success rate was 88%.

CONCLUSIONS

Instead of creating a side hole in the lacrimal sac as proposed by most endoscopic DCR studies, we advocate total diversion of tear flow by performing a terminal DCR opening that would further improve the success rate of endoscopic DCR, particularly in cases of idiopathic and partial obstruction.

Gadolinium-enhanced magnetic resonance dacryocystography in patients with epiphora

PURPOSE

Digital subtraction dacryocystography (DS-DCG) is considered the "gold standard" in the assessment of the nasolacrimal duct system but fails to delineate the soft tissue structures that surround the lacrimal drainage apparatus. The goal of this study was to compare high resolution MR surface coil imaging with DS-DCG to determine the value of gadolinium-enhanced MR dacryocystography (MR-DCG) in patients with epiphora.

METHOD

We performed bilateral MR-DCG and unilateral DS-DCG in 11 patients (aged 3-70 years) with epiphora using Gd-DTPA-containing eyedrops (Magnevist; 78.63 mg of Gd/ml diluted in a sterile 0.9% NaCl solution 1:100) and a water-soluble contrast medium (Omnipaque; 677 mg of Iohexol/ml). Radiographic and MR findings were separated and reviewed by two radiologists who were blinded to patients' names and histories. Afterwards, the passage of the contrast material was compared in the two procedures. The gold standard was defined as the distal-most point of the contrast material identified on either study.

RESULTS

Obstruction of the nasolacrimal duct system was diagnosed with a sensitivity of 100% with both MR-DCG and DS-DCG. With MR-DCG, the two readers correctly diagnosed the location of an obstruction in 67 and 89% and with DS-DCG in 56 and 67%. With MR-DCG, contrast material was traced further distally than with DS-DCG in three patients. DS-DCG was superior in only one case in which MR-DCG failed to delineate fistulas distal to the nasolacrimal sac.

CONCLUSION

Our data suggest that MR-DCG is suitable for assessing drainage problems of the nasolacrimal duct system, giving additional information concerning the surrounding soft tissue structures. Further studies are required to show whether MR-DCG can replace DS-DCG as the gold standard in the assessment of the nasolacrimal duct system.

Rhinostomies: an open and shut case?

AIMS

To analyse bone fragments from rhinostomies of patients undergoing revisional dacryocystorhinostomy, looking for evidence of new bone formation.

METHODS

14 consecutive patients undergoing secondary lacrimal surgery were included in this study. In each case the existing rhinostomy was enlarged with bone punches, care being taken to use the punches with the jaws cutting perpendicularly to the edge of the rhinostomy, to allow accurate orientation of the specimens. The fragments were examined histologically for evidence of new bone formation.

RESULTS

Histological sections showed fragments of bone with variable fibrosis at the edge of the rhinostomy. There was evidence of only very little new bone formation.

CONCLUSION

This study has clearly shown that, at the edge of a rhinostomy, healing is predominantly by fibrosis and there is only very limited new bone formation.

Comparison between nasolacrimal syringing/probing, macrodacryocystography and surgical findings in the management of epiphora

AIMS

Macrodacryocystography (MDCG) has been shown to be highly sensitive in evaluating the lacrimal drainage system. We aimed to compare the results of syringing/ probing with MDCG, and with surgical findings where available. We also aimed to determine whether MDCG is advisable in addition to syringing/probing when investigating epiphora.

METHODS

In a retrospective study, we looked at the records of 76 consecutive patients (86 eyes) presenting with epiphora over a period of 2 years (January 1993 to December 1994). All patients underwent syringing/probing and subsequent MDCG to determine the presence and level of nasolacrimal block. The results were then compared with surgical findings where available (46 eyes, 53%).

RESULTS

Surgical findings were predicted by MDCG in 95.5% of cases but in only 54% by probing. Probing findings agreed with MDCG in only 51% of cases. The main areas of disagreement were the presence of canalicular blocks and the presence of more than one block at different levels.

CONCLUSION

A combination of syringing/ probing and MDCG provides the most accurate pre-operative lacrimal assessment and should predict all the canalicular stenoses requiring intubation. In addition, MDCG can predict physiological duct blocks beyond canalicular blocks and thus alter surgical management.

The frequency of entry into an ethmoidal sinus when performing a dacryocystorhinostomy

Ethmoidal sinuses intervening between the lacrimal sac and the nose can cause confusion when performing a dacryocystorhinostomy (DCR). This study aimed to assess the frequency of entry into ethmoidal sinuses when performing a DCR and to identify any helpful distinguishing features, at surgery, between the ethmoidal and nasal spaces. Ethmoidal sinuses were initially entered in 23 of 50 standard DCRs (46%) in which the ostium was performed via the standard lacrimal fissure. Nasal mucosa was found to be 2 to 3 times thicker than ethmoidal sinus mucosa and less friable. Being aware of the risk of entering an ethmoidal sinus and of the anatomical differences between ethmoidal and nasal tissue greatly aids location during surgery and allows edge-to-edge suturing of sac mucosa to nasal mucosa in all cases.

Nuclear dacryoscintigraphy: its role in oral and maxillofacial surgery

Obstruction of the lacrimal drainage apparatus may result in excessive tearing or epiphora. This may occur as a result of a traumatic injury or accumulation of debris, mucus, or pus. In nuclear dacryoscintigraphy, a radioactive solution is introduced into the conjunctival sac by pipette and allowed to follow the flow of the tear solution through the lacrimal drainage system. This article will review normal lacrimal anatomy and indications for nuclear dacryoscintigraphy in oral and maxillofacial surgery.

Computed tomography dacryocystography

Twenty-one patients with epiphora were examined by conventional dacryocystography, using Lipiodol as a contrast medium, and CT dacryocystography, using a water soluble contrast medium. In the latter, the material was not introduced under pressure but three or four drops were administered, providing a physiological method of investigation. Subsequently, CT dacryocystography provides functional information about lacrimal disorders and is easy to use.

Technical note: computed tomographic dacryocystography

The technique of computed tomographic dacryocystography is described. It was developed in response to the pre-operative imaging requirements for transnasal endoscopic dacryocystorhinostomy, a new minimally invasive operation performed as a primary procedure to relieve epiphora. However, it is also helpful in the assessment of patients after failed conventional external dacryocystorhinostomy when the information provided will help to determine the subsequent surgical approach. In addition the technique will assist surgical planning in cases of epiphora associated with sinus surgery, facial trauma and maxillofacial tumours by determining the site and extent of pathology.

Gadolinium magnetic resonance imaging dacryocystography

A 1:100 solution of 48% gadopentolate in liquid tear solution was used in magnetic resonance dacryocystography to image the canaliculi, nasolacrimal sac, and nasolacrimal duct. It was administered as an eyedrop, one drop every minute for five minutes, immediately before scanning in six normal and five abnormal nasolacrimal outflow systems. In cases of nasolacrimal obstruction, the dilute gadolinium solution was injected through the canaliculus immediately before scanning. A three-inch surface coil enhanced the detail of soft-tissue structures such as the canaliculi and lacrimal sac. In the evaluation of complex tearing disorders such as congenital, neoplastic, postsurgical, and posttraumatic nasolacrimal obstruction, gadolinium lacrimal contrast adds useful information to magnetic resonance images of the lacrimal outflow system. Because of the expense of the test, we do not recommend it as a routine examination.

CT-dacryocystography for nasolacrimal duct obstruction following paranasal sinus surgery

Nasolacrimal duct obstruction and consequent epiphora is a complication that may develop in some patients following paranasal sinus surgery. We describe the technique of CT-dacryocystography which entails contrast injection of the lacrimal system and simultaneous computed tomography (CT) scanning of the facial structures. This technique provides concurrent information regarding obstruction of the nasolacrimal duct and the presence of disease recurrence or persistence in the adjacent paranasal sinuses. The role of CT-dacryocystography prior to endoscopic dacryocystorhinostomy is discussed briefly.