Clinical and radiological characteristics of odontogenic orbital cellulitis.

PURPOSE: To assess the radiological features and clinical outcomes of odontogenic orbital cellulitis. METHOD: Multi-centre retrospective study of odontogenic orbital cellulitis. Primary outcomes assessed were causal organism(s), clinical signs, radiological findings, management and visual outcomes. RESULTS: Four patients with odontogenic orbital cellulitis were identified for inclusion. There was an equal proportion of men and women with a mean age of 43 years (range 25-56 years). All patients presented with an orbital compartment syndrome, with visual acuity of counting fingers (n = 1, 25%), hand movements (n = 1, 25%) and no perception of light (n = 2, 50%). The organisms implicated were Streptococcus milleri (n = 3, 75%) and Streptococcus constellatus (n = 1, 25%). MRI findings showed a subperiosteal abscess was present in all cases, which was characterised radiologically as a T1-hyperintense, T2 minimally hyperintense collection with restricted diffusion and a low apparent diffusion coefficient signal. Final visual acuity ranged from 6/6 to no light perception. One patient required an orbital exenteration due to extensive necrosis with sepsis and systemic deterioration. CONCLUSIONS: Odontogenic orbital cellulitis carries a serious risk of vision loss with a propensity to present with an orbital compartment syndrome secondary to Streptococcus species. Outcomes were highly variable, with two cases progressing to blindness of which one required an orbital exenteration.

Differentiation of bacterial orbital cellulitis and diffuse non-specific orbital inflammation on magnetic resonance imaging.

PURPOSE: To examine the radiological differences between bacterial orbital cellulitis (OC) and diffuse non-specific orbital inflammation (DNSOI) on magnetic resonance imaging (MRI). METHODS: Retrospective study of patients with OC and DNSOI with an MRI orbital scan. Localised orbital inflammation (e.g., idiopathic dacryoadenitis and myositis), quiescent orbital inflammation and pre-septal cellulitis were excluded. RESULTS: Thirty-two patients presenting between 2008 and 2023, including twenty-one OC patients (mean age: 42.5 ± 24.9 years old, male: 6), and eleven DNSOI patients (mean age: 52.3 ± 17.8 years old, male: 16). Both OC and DNSOI demonstrate orbital fat contrast-enhancement. However, whilst OC demonstrated a hyperintense T2 signal (P < 0.001), variable signal was observed in DNSOI, with a hypointense T2 signal more suggestive of DNSOI (P = 0.012). When the lacrimal glands were involved, indistinct margins were more likely in OC (P < 0.001), whilst gross enlargement and contrast-enhancement was observed in DNSOI (P = 0.032 and 0.017, respectively). Peripheral contrast-enhancement of the extraocular muscle (EOM) (P = 0.002) was more common in OC, whilst DNSOI demonstrated variable contrast-enhancement throughout the affected EOM (P < 0.001). The presence of contralateral abnormalities, such as lacrimal gland enlargement and EOM involvement, are more suggestive of DNSOI. CONCLUSION: Several MRI features, beyond overt sinogenic disease, may help to differentiate OC from DNSOI, including the orbital fat signal intensity, EOM and/or lacrimal gland involvement, and contralateral orbital abnormalities. However, these features may not be specific, and thus highlights the ongoing radiological dilemma clinicians are faced when tasked with differentiating between infectious and non-infectious orbital inflammatory disease.

Fatty infiltration of extraocular muscles on magnetic resonance imaging.

PURPOSE: To investigate the prevalence of fatty infiltration in normal orbits using magnetic resonance imaging (MRI) and its impact on muscle diameters. METHODS: A retrospective analysis was conducted on normal orbits in patients who underwent coronal T1-weighted MRI. Fatty infiltration was defined by a hyperintense signal within the extraocular muscle. Fatty infiltration area was calculated by dividing the cross-sectional fat area by the sum of the muscle and fat area in the coronal plane. Muscle diameters were measured perpendicular to the muscle belly at their maximum and the mean diameters of the infiltrated muscles were compared with the non-infiltrated muscles. RESULTS: Seventy-six orbits from 76 participants with a mean age of 55.7 ± 18 years were included. Fatty infiltration in at least one muscle was seen in 57 (75%) of participants. When infiltration was present, inferior rectus was most commonly involved (98%). The area of fatty infiltration ranged from 6% to 42%, with 5 participants in the <10% group, 36 in the 10-20% group, 20 in the 20-30% group, 9 in the 30-40% group and 2 in the 40-50% group. Participants with fatty infiltration were significantly older (mean 61 ± 15 years vs 40 ± 16 years, p < .01) and had a higher proportion of males (56% vs 16%, p < .01). No significant difference in muscle diameters were found between infiltrated and healthy muscles. CONCLUSION: Fatty infiltration of the extraocular muscles is a reasonably common finding in normal orbits, most commonly involves the inferior rectus muscle and is associated with increasing age.

Orbital Myeloma and Plasmacytoma: An Australian Study.

PURPOSE: The purpose of this study was to provide Australian data on the clinical and radiological features and outcomes in patients with orbital plasmacytomas. METHODS: Multicentre retrospective review of orbital plasmacytoma and orbital involvement in multiple myeloma (MM) from 2005 to 2022 in Australia. RESULTS: Twenty-one participants were identified. The median age was 62 years (range 34-88 years), and 11 (52%) were females. Eighteen (84%) had a known diagnosis of MM prior to their orbital presentation, with all patients eventually being diagnosed with systemic MM. Thirteen (72%) were receiving active treatment for systemic myeloma on presentation, while 3 (17%) were in remission. All but 1 had unilateral orbital involvement (n = 20, 95%). Common presenting symptoms and signs were decreased visual acuity (n = 13, 62%), proptosis (n = 11, 52%), limited motility (n = 15, 71%), and optic neuropathy (n = 5, 24%). Radiologically, 15 (71%) involved the superotemporal orbit, 7 (33%) inferotemporal orbit, and 16 (76%) involved ≥1 extraocular muscle. Sixteen (76%) were biopsied and confirmed orbital plasmacytoma on histopathology. Treatment modalities included intravenous and oral steroids (n = 7, 33%), chemotherapy (n = 9, 43%), radiotherapy (n = 13, 62%), stem cell transplant (n = 3, 14%), and surgical debulking and decompression (n = 3, 14%). Mortality was high, with 15 (71%) having MM-related mortality. CONCLUSIONS: This is the largest cohort of Australian data on orbital plasmacytomas. Most patients have a diagnosis of systemic MM at presentation. It is crucial to recognize and treat these patients early due to a poor systemic prognosis.

Clinico-radiological features of optic nerve sheath schwannoma: Review and illustrative case.

The optic nerve sheath is a rare site for schwannoma, to our knowledge 19 optic nerve sheath schwannoma (ONSS) cases have been reported. Difficulty can arise in diagnosis as imaging findings can be relatively non-specific. We describe a case of ONSS that mimicked orbital cavernous venous malformation pre-operatively. A 43-year-old woman presented with right subacute visual loss, reduced vision to 6/48 and signs of optic neuropathy. Endocapsular excision of the mass, which was adherent to the optic nerve, was accomplished from an endoscopic endonasal approach utilizing a 5-hand technique of retrocaruncular dissection. Histology showed spindle-shaped tumour cells with S100 positivity, consistent with ONSS. At 6 months post-operatively vision had improved to 6/6. We show that an endoscopic endonasal approach, augmented by transcaruncular retraction, can be utilized to excise ONSS with an excellent outcome. We review published cases of ONSS, including demographic and clinical features, differential diagnosis based on radiological features, and described outcomes, which are generally poor.

Advances in Understanding and Management of IgG4-Related Ophthalmic Disease.

Immunoglobulin G4-related ophthalmic disease (IgG4-ROD) is an emerging, immune-mediated fibroinflammatory orbital disease, characterized by tumefactive lesions with noticeable IgG4+ plasma cell infiltration and distinctive pathohistological features. This disease is often associated with elevated serum IgG4 concentrations. IgG4-ROD may affect any ophthalmic tissues, particularly the lacrimal gland, extraocular muscles, and trigeminal nerves. Although the exact pathogenic role of IgG4 antibodies remains unclear, B-cell depleting agents have been reported to be an effective treatment. The diverse clinical manifestations of IgG4-ROD complicate diagnosis, and without prompt treatment, visual-threatening complications such as optic neuropathy may arise. Recent advances in understanding and managing IgG4-ROD have revolutionized the diagnosis and treatment of this emerging disease. This review article aims to provide a comprehensive overview of the latest advancements in the field of IgG4-ROD.

Non-infectious hypertrophic pachymeningitis associated with orbital inflammatory disease: a pooled analysis.

PURPOSE: To describe four cases of non-infectious hypertrophic pachymeningitis (HP)-associated with orbital inflammatory disease (OID). This study summarises the clinico-radiological features, outcomes, and management of HP-associated OID. METHODS: Retrospective case-series of patients with radiological evidence of HP and OID. Comprehensive literature review of all published English-language non-infectious causes of HP-associated OID. Reference lists were screened for inclusion of relevant articles. RESULTS: Thirty-seven cases of HP-associated OID (Mean age: 49.2 ± 17.4 years old; Male: 15) were identified, including four cases from our institution. Aetiologies included ANCA-associated vasculitis (12/37), non-specific/idiopathic (11/37), IgG4/multifocal fibrosclerosis (11/37), neurosarcoidosis (1/37), inflammatory myofibroblastic tumour (1/37), and giant cell arteritis (1/37). Orbital pain, headache, visual deterioration, and cranial nerve palsies were common clinical presentations. Both "focal" and "diffuse" HP were observed, with the most common sign of orbital involvement being an inflammatory orbital mass, typically with orbital apex involvement. Orbital myositis and dacryoadenitis were less common. The cavernous sinus was the most common site of extra-orbital inflammation. There was no single differentiating specific radiological feature between non-specific and specific forms of HP-associated OID. CONCLUSION: The clinico-radiological manifestations of HP-associated OID differ from those described in isolated HP or OID. There is no single specific radiological marker differentiating non-specific/idiopathic disease from secondary causes; however, the co-existence of HP in OID should prompt suspicion of an underlying cause. The disease may be refractory or resistant to initial treatment, although guidelines surrounding its management and the long-term prognosis remain to be determined.

Myxoma: An Unusual Aggressive Orbital Lesion.

Myxoma is a rare tumor that can be challenging to diagnose, with imaging findings that can be nonspecific. We present a case of a 21-year-old man who presented with a subacute history of right visual deterioration and proptosis. Imaging showed a large right superomedial orbital mass of 43 × 31 × 24 mm, which enhanced heterogeneously and was eroding the adjacent orbital roof and medial wall. An excisional biopsy was performed via a lid crease approach under transorbital endoscopic guidance. We review the clinical, radiological, and histological characteristics of myxoma. In addition, we highlight important associations with genetic syndromes including Carney complex and Mazabraud syndrome.

Topical dorzolamide for macular holes: A randomised, double-blind, placebo-controlled trial.

BACKGROUND: To assess topical dorzolamide as medical therapy for idiopathic full-thickness macular holes (FTMHs). METHODS: Randomised, double-blinded, placebo-controlled, single-centre clinical trial involving 32 patients with idiopathic small FTMHs (<400 µm $$ \upmu \mathrm{m} $$ ). Participants in both arms used topical dorzolamide 2% or saline thrice daily for 8 weeks with monthly OCT. Those with persisting FTMH underwent vitrectomy with ILM peel and gas tamponade. The primary outcome was the rate of FTMH closure at the end of treatment. RESULTS: Between 6 March 2020 and 16 June 2023, 32 eligible patients were enrolled: 16 participants in each arm. All participants in both groups were included in the final analysis. At the final visit, 3 of 16 (18.8%) patients in both the topical dorzolamide and placebo group demonstrated closure. There was no statistically significant difference in the proportion of FTMH closure between the control and treatment group (p = 1.00), nor statistically significant difference in the mean change in best corrected visual acuity (BCVA; p = 0.909). There was no difference in the change in FTMH diameter between groups (p = 0.225). No serious adverse events were reported in either group. CONCLUSION: Topical dorzolamide was safe but not superior to placebo in the functional and anatomical outcomes of FTMH.

Normative Measurements of the Infraorbital Nerve by Magnetic Resonance Imaging in an Australia Cohort.

PURPOSE: To report the normative dimensions of the infraorbital nerve on fat-suppressed gadolinium-enhanced MRI and correlate with patient demographics in an Australian cohort. METHODS: A retrospective review of patients who underwent coronal fat-suppressed gadolinium T1-weighted MRI from September 2021 to December 2023. One hundred sixty-eight orbits were included. The maximum diameter of the infraorbital nerve and the optic nerve sheath was measured. Orbits were excluded if there was unilateral or bilateral pathology of the infraorbital nerve or optic nerve sheath, incomplete MRI sequences, poor image quality, or indiscernible infraorbital nerve on radiological examination. RESULTS: The mean age of participants was 58 ± 16 years, and 50% were females (n = 42). The mean normative measurements (mean ± standard deviation) on coronal T1-weighted imaging: optic nerve sheath, 5.08 ± 0.67 mm. On coronal fat-suppressed gadolinium T1-weighted imaging: infraorbital nerve, 0.89 ± 0.22mm. No significant differences were found between male or female participants in both the infraorbital nerve (p = 0.757) or optic nerve sheath (p = 0.646). There was no significant correlation between age and mean diameter of the infraorbital nerve (r = 0.077, p = 0.320) or optic nerve sheath (r = 0.075, p = 0.336). Additionally, no significant difference was identified between the mean diameter of the infraorbital nerve (p = 0.079) and optic nerve sheath (p = 0.120) across age groups. The mean infraorbital nerve to optic nerve sheath ratio was 0.18 ± 0.00. CONCLUSION: Normative dimensions of the infraorbital nerve may be used to identify enlargement in conditions such as IgG4-related ophthalmic disease and reactive lymphoid hyperplasia.

Primary orbital apocrine adenocarcinoma: case report and literature review.

Primary apocrine adenocarcinoma (PAA) originating from the orbit is a rare malignant neoplasm. We present the case of a 61-year-old-male with PAA of the orbit. The patient underwent a right orbital exenteration, neck dissection, and adjuvant radiotherapy. Orbital exenteration is commonly performed as the primary intervention for PAA of the orbit. The role of adjuvant radiotherapy to prevent local recurrence is unclear and may be determined on a case-by-case basis.

Radiological differentiation between bacterial orbital cellulitis and invasive fungal sino-orbital infections.

PURPOSE: Invasive fungal orbital infections (IFOI) may be difficult to differentiate from sinogenic bacterial orbital cellulitis (OC). This study investigates the features differentiating OC from IFOI on magnetic resonance imaging (MRI). METHODS: Retrospective study of adult patients with sinogenic OC and IFOI with pre-intervention MRI. Patients without post-septal involvement, non-sinogenic OC (e.g.: secondary to trauma) and poor-quality scans were excluded. Independent Sample's t test and Fisher's exact test were conducted with p < 0.05 deemed statistically significant. RESULTS: Eleven cases each of OC (Mean age: 41.6 ± 18.4 years-old, Male: 10) and IFOI (Mean age: 65.0 ± 16.6 years-old, Male: 9) between 2006 and 2023. IFOI patients were older, more likely immunocompromised and had a lower mean white-cell count (p value = 0.005, 0.035 and 0.017, respectively). The ethmoid and maxillary sinuses were most commonly involved in both entities. Pre-septal and lacrimal gland involvement were more common in OC (p = 0.001 and 0.008, respectively). Infiltrative OC orbital lesions were poorly demarcated, whilst those in IFOI were expansile/mass-like invading the orbit from the adjacent paranasal sinuses. Specific IFOI features included loss-of-contrast-enhancement (LoCE) of paranasal sinus tissues with orbital extension. Extra-orbital and -sinonasal extension indicative of IFOI included contiguous skull base or pterygopalatine fossa involvement, retro-antral and masticator space stranding and vasculitis. CONCLUSION: This study describes the key MRI features of IFOI including differentiating markers from OC. These specific features, such as LoCE of the paranasal and orbital soft tissues, the location and pattern of contiguous soft-tissue involvement, provide expedient identification of IFOI which necessitate early surgical intervention for microbiological confirmation of an invasive fungal pathology.

Microbiology of acute bacterial dacryocystitis: a tertiary institutional experience in South Australia.

PURPOSE: To provide a comprehensive microbiological profile of bacterial dacryocystitis in South Australia. By identifying the specific microorganism and antibiotic susceptibility, this study intends to aid ophthalmologists in choosing appropriate empirical antibiotic therapies and development of evidence-based clinical guidelines. METHOD: A retrospective study was conducted at the Royal Adelaide Hospital (RAH) over five years (2018-2023) of patients with acute dacryocystitis. The study included 43 patients, and data encompassed demographic information, clinical presentation, microbiological analysis, management, and outcomes. Patients with chronic dacryocystitis were excluded. RESULTS: Among the 43 patients included in the study (female 28 (65%), mean age: 64 years old), the most common clinical features were pain (74%) and swelling (70%). Organisms were identified in 49% of patients, with the predominant bacteria being Staphylococcus aureus (42%), Streptococcus species (19%), and Escherichia coli (8%). Aggregatibacter species (8%), Morganella morganii (4%), Enterobacter cloaceae (4%), Hafnia alvei (4%), mixed anaerobes (4%), E coliforms (4%) and Pseudomonas aeruginosa (4%) were also identified. The most frequently prescribed empirical antibiotics were amoxicillin-clavulanic acid (50%), flucloxacillin (33%) and cefalexin (18%). CONCLUSION: The microbiological trends of acute dacryocystitis have largely remained consistent, with a predominance of Gram positive organisms. This is the most recent profile analysis of acute dacryocystitis in South Australia and will help form evidence-based clinical guidelines.

Primary Dacryocystorhinostomy for Acute Dacryocystitis: A Systematic Review.

INTRODUCTION: Acute dacryocystitis is a common condition occurring secondary to nasolacrimal duct obstruction. We aim to assess the efficacy of primary dacryocystorhinostomy for the management of acute dacryocystitis. METHODS: A systematic search of the databases PubMed/MEDLINE, Embase, and CENTRAL was performed to December 2023. Data extraction and risk of bias analysis was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RESULTS: Fourteen articles fulfilled inclusion criteria. The results demonstrated that for the treatment of acute dacryocystitis, primary dacryocystorhinostomy (DCR) is anatomically and functionally efficacious, with low complication rates and minimal risk of recurrence. The anatomical success rates for primary endonasal DCR (EnDCR) were 81.8-100%, 83.8-87.5% in delayed EnDCR and 66-100% in delayed external DCR (ExDCR). Functional success was generally defined as a subjective absence of epiphora, which was achieved in 86.4-92.0% of primary EnDCR, and 0-89.5% of the delayed ExDCR cohorts. Two randomized controlled trials established equivalent rates of functional success between primary versus delayed EnDCR (87.5% vs 87.5% and 91.3% vs 92.3%). Increased perioperative bleeding was recorded in 27.8% of primary EnDCR cases in 1 study. ExDCR was infrequently associated with postoperative fistula and scar formation and cicatricial punctal ectropion. The mean length of admission trended to be shorter when the procedure was performed closer to the acute presentation. The admission time for all primary EnDCR cases varied between 1 and 7 days. CONCLUSION: Primary dacryocystorhinostomy is an efficacious and safe management option for acute dacryocystitis. Further analyses of health-economics are required.

Artificial intelligence to automate assessment of ocular and periocular measurements.

PURPOSE: To develop and validate a deep learning facial landmark detection network to automate the assessment of periocular anthropometric measurements. METHODS: Patients presenting to the ophthalmology clinic were prospectively enrolled and had their images taken using a standardised protocol. Facial landmarks were segmented on the images to enable calculation of marginal reflex distance (MRD) 1 and 2, palpebral fissure height (PFH), inner intercanthal distance (IICD), outer intercanthal distance (OICD), interpupillary distance (IPD) and horizontal palpebral aperture (HPA). These manual segmentations were used to train a machine learning algorithm to automatically detect facial landmarks and calculate these measurements. The main outcomes were the mean absolute error and intraclass correlation coefficient. RESULTS: A total of 958 eyes from 479 participants were included. The testing set consisted of 290 eyes from 145 patients. The AI algorithm demonstrated close agreement with human measurements, with mean absolute errors ranging from 0.22 mm for IPD to 0.88 mm for IICD. The intraclass correlation coefficients indicated excellent reliability (ICC > 0.90) for MRD1, MRD2, PFH, OICD, IICD, and IPD, while HPA showed good reliability (ICC 0.84). The landmark detection model was highly accurate and achieved a mean error rate of 0.51% and failure rate at 0.1 of 0%. CONCLUSION: The automated facial landmark detection network provided accurate and reliable periocular measurements. This may help increase the objectivity of periocular measurements in the clinic and may facilitate remote assessment of patients with tele-health.

Ameloblastic Carcinoma With Orbital Invasion.

Ameloblastic carcinomas are malignant tumors arising from the odontogenic epithelium and defined as having features of ameloblastic differentiation in addition to cytological features of malignancy. Orbital involvement is rare and generally involves invasion of the orbital floor, apex, or soft tissue. This report describes an advanced presentation of ameloblastic carcinoma with orbital invasion and provides a review of the literature. A 58-year-old male presented with a 2-year history of a mid-facial mass, causing intracranial invasion and distortion of most skull foramina, nasopharynx, nasal cavity, and both orbits. Notably, there was an en-plaque pattern of circumferential tracking of the tumor along both orbital walls without invasion beyond the extraconal space, causing compression of the orbital apex and proptosis. Histology demonstrated nests of ameloblastic carcinoma and the advanced tumor was deemed nonresectable, with treatment being palliative.

Asymmetric proptosis in thyroid eye disease.

PURPOSE: Patients with thyroid eye disease (TED) can present with asymmetric disease. The purpose of this study was to evaluate the prevalence of asymmetric TED in an Australian cohort and investigate clinical, biochemical, and radiological associations of asymmetric TED. METHODS: This was a retrospective study of patients with TED who underwent Hertel exophthalmometry and orbital computed tomography (CT) scans. Asymmetry was defined as a difference in the globe protrusion of ≥ 3 mm using Hertel exophthalmometry. Data was collected on patient demographics, clinical disease presentation, thyroid function tests and antibody levels. Muscles volumes were determined by manually segmenting the extraocular muscles on CT scans using a commercially available software. RESULTS: 172 orbits from 86 patients were included in the study. 28 (33%) patients had asymmetric TED. No significant differences were observed in age, gender, thyroid hormone status, anti-thyroid peroxidase levels, thyroid stimulating hormone receptor antibodies, disease activity status, or dysthyroid optic neuropathy between the asymmetric and non-asymmetric groups. The extraocular muscle volumes were significantly higher in the asymmetric orbit compared to its contralateral orbit. CONCLUSION: Asymmetric TED is a reasonably common occurrence in the course of TED. It is associated with higher extraocular muscle volumes, suggesting muscle enlargement as one of the underlying contributors to asymmetric proptosis. Thyroid eye disease should be considered in the differential of asymmetric orbital inflammatory disease.

Dacryocystorhinostomy videos on YouTube as a source of patient education.

BACKGROUND: To determine the quality and reliability of DCR YouTube videos as patient education resources and identify any associated factors predictive of video quality. METHODS: A YouTube search was conducted using the terms "Dacryocystorhinostomy, DCR, surgery" on 12th of January 2022, with the first 50 relevant videos selected for inclusion. For each video, the following was collected: video hyperlink, title, total views, months since the video was posted, video length, total likes/dislikes, authorship (i.e. surgeon, patient experience or media companies) and number of comments. The videos were graded independently by a resident, a registrar and an oculoplastic surgeon using three validated scoring systems: the Journal of the American Medical Association (JAMA), DISCERN, and Health on the Net (HON). RESULTS: The average number of video views was 22,992, with the mean length being 488.12 s and an average of 18 comments per video. The consensus JAMA, DISCERN and HON scores were 2.1 ± 0.6, 29.1 ± 8.8 and 2.7 ± 1.0, respectively. This indicated that the included videos were of a low quality, however, only DISCERN scores had good interobserver similarity. Videos posted by surgeons were superior to non-surgeons when considering mean JAMA and HON scores. No other factors were associated with the quality of educational content. CONCLUSION: The quality and reliability of DCR related content for patient education is relatively low. Based on this study's findings, patients should be encouraged to view videos created by surgeons or specialists in preference to other sources on YouTube.

A case of disseminated nocardiosis with orbital apex involvement and endophthalmitis.

Nocardia is a rare cause of ocular infections and most commonly occurs secondary to trauma. Systemic Nocardiosis may have ocular involvement in rare cases. We report a case of disseminated nocardiosis with orbital apex involvement and endophthalmitis in an immunocompromised patient. The patient presented with respiratory sepsis, and later developed complete ptosis and ophthalmoplegia in the left eye. This was on the background of treatment with high-dose prednisolone. Magnetic resonance imaging showed enhancement of the entire clivus, extending into the left orbital apex and cavernous sinus. The patient was initially treated empirically for CNS tuberculosis. Bronchoscopic cultures returned positive for Nocardia farcinica, and the patient was treated with trimethoprim/sulfamethoxazole and weaned off previous corticosteroids.

A Brief History of Lacrimal Bypass Techniques.

PURPOSE: Lacrimal bypass is the creation of a fistula connecting the conjunctiva with the lacrimal sac or nasal cavity. Bypass is indicated in canalicular obstruction or agenesis; sac absence, destruction or prior excision; lacrimal pump failure; or dacryocystorhinostomy failure. We aim to review the various techniques that have been developed over the last century for lacrimal bypass. METHODS: We conducted a comprehensive literature review of techniques which have focused on creating a conduit extending from the conjunctiva or canaliculi to the lacrimal sac, or extending that bypass to the nasal cavity bypass. RESULTS: The main techniques reviewed include canaliculodacryocystorhinostomy, conjunctivodacryocystostomy, conjunctivorhinostomy, conjunctivodacryocystorhinostomy, and conjunctivoductivodacryocystorhinostomy. CONCLUSION: Lacrimal bypass surgery has evolved due to innovation in microsurgical techniques, instruments and materials. Conjunctivodacryocystorhinostomy with Jones tube insertion is the predominant bypass technique, reflecting a culmination of historical developments. Understanding the variety of lacrimal bypass techniques is important for exploring alternative options when necessary.