Clinico-epidemiological analysis of 1000 cases of orbital tumors

Unveiling the Enigma: Gigantic primary de novo poorly-differentiated ductal adenocarcinoma of the lacrimal gland with aggressive features. A case report and literature review

Primary ductal adenocarcinoma (PDA) of the lacrimal gland is a rare and aggressive malignancy originating from ductal epithelial cells. Its rarity and diverse clinical presentations pose significant diagnostic challenges, emphasizing the need for accurate diagnosis and appropriate management strategies. The study presents an intriguing case of a 50-year-old man with a large de novo primary ductal adenocarcinoma of the lacrimal gland, initially misdiagnosed as a meningeal solitary fibrous tumor due to its atypical clinical presentation of "down and out" proptosis. The case underscores the importance of histopathology to achieve a correct diagnosis and guide management decisions. Despite aggressive treatment approaches, the prognosis of primary ductal adenocarcinoma patients remains grim due to its aggressive behavior and tendency for recurrence and metastasis. The present case study emphasizes that a differential of primary ductal adenocarcinoma should be considered despite the presence of anomalous clinical and radiological presentation.

Imaging of the skull base and orbital tumors

The skull base and orbit have complicated anatomical structures where various tumors can occur. The tumor may present with neurological symptoms; however, its diagnosis is clinically difficult owing to accessibility issues. Therefore, diagnostic imaging is crucial in assessing tumors in the skull base and orbit and guiding subsequent management. Notably, some tumors have a predilection for a specific site of origin, and identifying the site of origin on imaging can help narrow the differential diagnosis. At the skull base, chordomas typically occur in the clivus, chondrosarcomas in the paramedian areas, paragangliomas in the jugular foramen, neurogenic tumors, and perineural spread in the neural foramen. Among orbital tumors, cavernous hemangiomas usually occur in the intraconal space, and pleomorphic adenomas and adenoid cystic carcinomas occur in the lacrimal glands. Some skull base and orbital tumors exhibit distinctive imaging features. Chordomas and chondrosarcomas of the skull base show high signal intensities on T2-weighted images, with chondrosarcomas often displaying cartilaginous calcifications. Paragangliomas are characterized by their hypervascular nature. In the orbit, cavernous hemangiomas and pleomorphic adenomas present unique dynamic patterns. Immunoglobulin G4-related disease forms lesions along the nerves. Identifying the tumor origin and its imaging characteristics can help narrow the differential diagnosis of skull base and orbital tumors.

Evaluation of the specificity of trigeminal nerve enlargement in the diagnosis of IgG4-related ophthalmic disease

PURPOSE

Enlargement of the trigeminal nerve is observed in 20-53% of patients with IgG4-related ophthalmic disease (IgG4-ROD) and is known to be a useful finding for the diagnosis of IgG4-ROD. On the other hand, enlargement of the trigeminal nerve has also been found at a certain frequency in orbital lymphoproliferative diseases other than IgG4-ROD. Therefore, we here re-evaluated the specificity of trigeminal nerve enlargement in the diagnosis of IgG4-ROD.

STUDY DESIGN

Retrospective, comparative study.

METHODS

A total of 149 consecutive cases of IgG4-ROD diagnosed at the Department of Ophthalmology, Tokyo Medical University Hospital were studied. As controls, 218 cases of orbital lymphoma, 13 cases of reactive lymphoid hyperplasia (RLH), and 117 cases of benign orbital tumors other than lymphoproliferative diseases were included. Enlargement of the trigeminal nerve (infraorbital or supraorbital nerve) in IgG4-ROD and all the control cases was evaluated on MRI or CT coronal images.

RESULTS

Enlargement of the trigeminal nerve was observed in 35 of the 149 cases (23.5%) of IgG4-ROD and in 7 of the 218 cases (3.2%) of lymphoma, with a significantly highly frequency in IgG4-ROD (P < .0001). No cases of trigeminal nerve enlargement were observed in the cases of RLH or benign orbital tumors. The sensitivity and the specificity of trigeminal nerve enlargement in the diagnosis of IgG4-ROD were 23.5% and 96.8%, respectively. Additionally, enlargement of the trigeminal nerve was significantly more common in men than in women (P < .028).

CONCLUSIONS

The present study indicates that trigeminal nerve enlargement is a characteristic imaging finding and has diagnostic value for IgG4-ROD.

Epidemiology and tumor microenvironment of ocular surface and orbital tumors on growth and malignant transformation

The ocular surface and orbit constitute unique microenvironments in the human body. Current advances in molecular research have deepened our understanding of tumor development in these regions. Tumors exhibit greater heterogeneity compared to normal tissues, as revealed by pathological and histological examinations. The tumor microenvironment (TME) plays a crucial role in the proliferation and progression of cancer cells. Factors from the external environment or the body's own inflammation and microcirculation interact within the TME, maintaining a delicate balance. Disruption of this balance, through uncontrolled signal pathway activation, can transform normal or benign tissues into malignant ones. In recent years, various systemic immunotherapies have been developed for cancer treatment. This study reviews the epidemiology of ocular surface and orbital tumors include squamous cell carcinoma, basal cell carcinoma, sebaceous carcinoma and lymphoma in conjunction with their occurrence, growth, and underlying mechanisms. We propose that by examining clinical histopathological images, we can identify specific and shared microscopic features of tumors. By collecting, classifying, and analyzing data from these clinical histopathological images, we can pinpoint independent diagnostic factors characteristic of tumors. We hope this study provides a basis for future exploration of the mechanisms underlying different ocular diseases.

Image-guided navigation in posterior orbital tumour surgery: a comparative cohort study

PURPOSE

The posterior orbit is a confined space, harbouring neurovascular structures, frequently distorted by tumours. Image-guided navigation (IGN) has the potential to allow accurate localisation of these lesions and structures, reducing collateral damage whilst achieving surgical objectives.

METHODS

We assessed the feasibility, effectiveness and safety of using an electromagnetic IGN for posterior orbital tumour surgery via a comparative cohort study. Outcomes from cases performed with IGN were compared with a retrospective cohort of similar cases performed without IGN, presenting a descriptive and statistical comparative analysis.

RESULTS

Both groups were similar in mean age, gender and tumour characteristics. IGN set-up and registration were consistently achieved without significant workflow disruption. In the IGN group, fewer lateral orbitotomies (6.7% IGN, 46% non-IGN), and more transcutaneous lid and transconjunctival incisions (93% IGN, 53% non-IGN) were performed (p = .009). The surgical objective was achieved in 100% of IGN cases, with no need for revision surgery (vs 23% revision surgery in non-IGN, p = .005). There was no statistically significant difference in surgical complications.

CONCLUSION

The use of IGN was feasible and integrated into the orbital surgery workflow to achieve surgical objectives more consistently and allowed the use of minimal access approaches. Future multicentre comparative studies are needed to explore the potential of this technology further.

Artificial intelligence-based differential diagnosis of orbital MALT lymphoma and IgG4 related ophthalmic disease using hematoxylin-eosin images

PURPOSE

To investigate the possibility of distinguishing between IgG4-related ophthalmic disease (IgG4-ROD) and orbital MALT lymphoma using artificial intelligence (AI) and hematoxylin-eosin (HE) images.

METHODS

After identifying a total of 127 patients from whom we were able to procure tissue blocks with IgG4-ROD and orbital MALT lymphoma, we performed histological and molecular genetic analyses, such as gene rearrangement. Subsequently, pathological HE images were collected from these patients followed by the cutting out of 10 different image patches from the HE image of each patient. A total of 970 image patches from the 97 patients were used to construct nine different models of deep learning, and the 300 image patches from the remaining 30 patients were used to evaluate the diagnostic performance of the models. Area under the curve (AUC) and accuracy (ACC) were used for the performance evaluation of the deep learning models. In addition, four ophthalmologists performed the binary classification between IgG4-ROD and orbital MALT lymphoma.

RESULTS

EVA, which is a vision-centric foundation model to explore the limits of visual representation, was the best deep learning model among the nine models. The results of EVA were ACC = 73.3% and AUC = 0.807. The ACC of the four ophthalmologists ranged from 40 to 60%.

CONCLUSIONS

It was possible to construct an AI software based on deep learning that was able to distinguish between IgG4-ROD and orbital MALT. This AI model may be useful as an initial screening tool to direct further ancillary investigations.

Prevalence of TERT Promoter Mutations in Orbital Solitary Fibrous Tumors

The orbital manifestation of a solitary fibrous tumor (SFT) is exceptionally rare and poses specific challenges in diagnosis and treatment. Its rather exceptional behavior among all SFTs comprises a high tendency towards local recurrence, but it rarely culminates in metastatic disease. This raises the question of prognostic factors in orbital SFTs (oSFTs). Telomerase reverse transcriptase (TERT)-promoter mutations have previously been linked to an unfavorable prognosis in SFTs of other locations. We analyzed the prevalence of TERT promoter mutations of SFTs in the orbital compartment. We performed a retrospective, descriptive clinico-histopathological analysis of nine cases of oSFTs between the years of 2017 and 2021. A TERT promoter mutation was present in one case, which was classified with intermediate metastatic risk. Local recurrence or progress occurred in six cases after primary resection; no distant metastases were reported. Multimodal imaging repeatedly showed particular morphologic patterns, including tubular vascular structures and ADC reduction. The prevalence of the TERT promoter mutation in oSFT was 11%, which is similar to the prevalence of extra-meningeal SFTs of the head and neck and lower than that in other extra-meningeal compartments. In the present study, the TERT promoter mutation in oSFT manifested in a case with an unfavorable prognosis, comprising aggressive local tumor growth, local recurrence, and eye loss.

The poor prognosis of lacrimal gland adenocarcinoma: a clinical study and literature review

PURPOSE

The incidence of lacrimal gland adenocarcinoma is low. This study was designed to analyze the clinical and prognostic characteristics of lacrimal gland adenocarcinoma.

METHODS

This was a clinical study and literature review; 25 patients diagnosed with lacrimal gland adenocarcinoma by histopathology were enrolled and their medical history data were collected.

RESULTS

The incidence of bone destruction and surrounding tissue invasion was 52% and 44%, respectively. The incidence of distant metastasis of lacrimal gland adenocarcinoma was about 50%. The 5-year overall survival rate of death or metastasis was 33.5%. Age, sex, laterality, tumor size, pathology type, bone destruction, nerve or perineural invasion, invasion of peripheral tissue, T stage, AR, Her-2 and treatment had no significant correlation with lacrimal adenocarcinoma's prognosis (P > 0.05), while the higher expression of Ki-67 may have higher risk of death or metastasis (P = 0.020).

CONCLUSION

The incidence of bone destruction and distant metastasis of lacrimal adenocarcinoma is high and the imaging examination is necessary to assess the risk of distant metastasis. The 5-year survival rate of death or metastasis is 33.5% and the high expression of Ki-67 predicts poor prognosis of lacrimal adenocarcinoma.

Stromal area differences with epithelial-mesenchymal transition gene changes in conjunctival and orbital mucosa-associated lymphoid tissue lymphoma

Purpose

To examine the molecular biological differences between conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma and orbital MALT lymphoma in ocular adnexa lymphoma.

Methods

Observational case series. A total of 129 consecutive, randomized cases of ocular adnexa MALT lymphoma diagnosed histopathologically between 2008 and 2020.Total RNA was extracted from formalin-fixed paraffin-embedded tissue from ocular adnexa MALT lymphoma, and RNA-sequencing was performed. Orbital MALT lymphoma gene expression was compared with that of conjunctival MALT lymphoma. Gene set (GS) analysis detecting for gene set cluster was performed in RNA-sequence. Related proteins were further examined by immunohistochemical staining. In addition, artificial segmentation image used to count stromal area in HE images.

Results

GS analysis showed differences in expression in 29 GS types in primary orbital MALT lymphoma (N=5,5, FDR q-value <0.25). The GS with the greatest difference in expression was the GS of epithelial-mesenchymal transition (EMT). Based on this GS change, immunohistochemical staining was added using E-cadherin as an epithelial marker and vimentin as a mesenchymal marker for EMT. There was significant staining of vimentin in orbital lymphoma (P<0.01, N=129) and of E-cadherin in conjunctival lesions (P=0.023, N=129). Vimentin staining correlated with Ann Arbor staging (1 versus >1) independent of age and sex on multivariate analysis (P=0.004). Stroma area in tumor were significant difference(P<0.01).

Conclusion

GS changes including EMT and stromal area in tumor were used to demonstrate the molecular biological differences between conjunctival MALT lymphoma and orbital MALT lymphoma in ocular adnexa lymphomas.

Machine Learning Model with Texture Analysis for Automatic Classification of Histopathological Images of Ocular Adnexal Mucosa-associated Lymphoid Tissue Lymphoma of Two Different Origins

PURPOSE

The purpose of this study was to develop artificial intelligence algorithms that can distinguish between orbital and conjunctival mucosa-associated lymphoid tissue (MALT) lymphomas in pathological images.

METHODS

Tissue blocks with residual MALT lymphoma and data from histological and flow cytometric studies and molecular genetic analyses such as gene rearrangement were procured for 129 patients treated between April 2008 and April 2020. We collected pathological hematoxylin and eosin-stained (HE) images of lymphoma from these patients and cropped 10 different image patches at a resolution of 2048 × 2048 from pathological images from each patient. A total of 990 images from 99 patients were used to create and evaluate machine-learning models. Each image patch of three different magnification rates at ×4, ×20, and ×40 underwent texture analysis to extract features, and then seven different machine-learning algorithms were applied to the results to create models. Cross-validation on a patient-by-patient basis was used to create and evaluate models, and then 300 images from the remaining 30 cases were used to evaluate the average accuracy rate.

RESULTS

Ten-fold cross-validation using the support vector machine with linear kernel algorithm was identified as the best algorithm for discriminating between conjunctival mucosa-associated lymphoid tissue and orbital MALT lymphomas, with an average accuracy rate under cross-validation of 85%. There were ×20 magnification HE images that were more accurate in distinguishing orbital and conjunctival MALT lymphomas among ×4, ×20, and ×40.

CONCLUSION

Artificial intelligence algorithms can successfully distinguish HE images between orbital and conjunctival MALT lymphomas.

Long-Term Surgical Outcome for Orbital Solitary Fibrous Tumors

PURPOSE

To report long-term outcomes after surgery for orbital solitary fibrous tumors.

METHODS

Retrospective review of patients with orbital solitary fibrous tumor, first seen between 1971 and 2022. Primary excisions were grouped as (A) surgically intact, (B) macroscopic, but with cell spillage, or (C) known incomplete excision.

RESULTS

Fifty-nine patients (31 female; 53%) presented at a mean age of 43.0 years (19-82 years), with 5 patients (8.5%) having malignant solitary fibrous tumors. Average follow up was 11.4 years (median 7.8; range 1-43 years). There were 28 of 59 (47%) group A patients with 1 of 28 (3%) having recurrence, 20 of 59 (34%) group B having 6 of 20 (30%) recurrences, and 11 of 59 (19%) group C with 9 of 11 (82%) recurrence ( p < 0.001 for recurrence rate). At a mean of 8.9 (range 1-23.6) years after initial treatment, continued local tumor growth was evident in 16 (27%) patients, with higher-grade recurrence in 3 of 14 (21%) cases. No patient had systemic disease at presentation, but 2 of 59 patients (3%) developed metastases at 22 and 30 years after first treatment. The 10-year progression-free survival was 94% (group A), 60% (group B), and 36% (group C). Tumor disruption or incomplete excision (groups B + C) carries the highest risk of tumor recurrence (hazard ratio 15.0; 95% confidence interval, 1.98-114; p = 0.009), with no correlation to tumor size or histology.

CONCLUSIONS

Orbital solitary fibrous tumors have a low recurrence rate with surgically intact excision; piecemeal excision, capsular disruption, or known incomplete resection have a high recurrence rate, which can occur decades later. Baseline postoperative scans is recommended, together with long-term clinical and interval imaging.

Presentation of orbital solitary fibrous tumours

AIMS

To evaluate presenting features of patients with orbital solitary fibrous tumours (SFTs), based on histological phenotype.

METHODS

A retrospective case-note review was performed for demographics and presenting features for patients with orbital SFTs. The tumours were classified as "Group IA" hypocellular SFT phenotype, "Group IB" haemangiopericytoma phenotype and low mitotic activity, and high-grade "Group II" haemangiopericytoma phenotype with high mitotic activity.

RESULTS

Sixty-four patients (34 female; 53%) presented at a mean age of 42.2 years (median 38; range 19-82), with Group II patients presenting at an older age (mean 53 years). Median symptom duration was 12 months for Groups IA and IB, compared to 4 months for Group II, the commonest symptoms being proptosis (53%), diplopia (41%), periorbital swelling (31%), and altered vision (19%). Mean LogMAR was 0.17 (median 0.0; range -0.2-4), and 14% had ipsilateral optic neuropathy, with no significant difference between the three groups. Non-axial displacement was noted in 69%, a palpable mass in 45%, and reduced eye movements in 59%; choroidal folds and optic disc swelling were recorded in 12% and 9%. SFTs were mostly extraconal (59%), within the superior and superonasal quadrants (44%), with an average estimated tumour volume of 4.9 ml (median 3.6; range 0.31-14.5 ml).

CONCLUSION

SFTs may present with impaired visual function (∼15%), fundal abnormalities (a fifth), globe displacement (two-thirds), and reduced ocular motility (over a half). High-grade tumours tend to present more than a decade later, with a shorter duration of symptoms.

Orbital inflammatory pseudotumor: new advances in diagnosis, pathogenesis, and treatment

Orbital inflammatory pseudotumor (OIP) is a benign, non-specific inflammatory disorder that commonly occurs in middle-aged adults and is usually unilateral but can occur bilaterally. Its clinical manifestations have tremendous clinical heterogeneity and vary according to the site of infiltration and the degree of lesions, including orbital pain, swelling, diplopia, proptosis, restricted eye movement, and decreased visual acuity. Clinical features, Image characteristics and pathological examinations often need to be evaluated to confirm the diagnosis. Currently, there is no systematic research on the pathogenesis of OIP, which may be related to immunity or infection. The first-line treatment is glucocorticoids. Radiotherapy, immunosuppressants, and biologics can be considered for treatment-resistant, hormone-dependent, or intolerant patients. In this review, we aim to summarize and focus on new insights into OIP, including new diagnostic criteria, pathogenesis, and discoveries in new drugs and treatment strategies. In particular, we highlight the literature and find that T cell-mediated immune responses are closely related to the pathogenesis of OIP. Further exploration of the mechanism and signaling pathway of T cells in the immune process will help to identify their therapeutic targets and carry out targeted therapy to treat refractory OIP and reduce the side effects of traditional treatments.

Maligne Neoplasien der Orbita

Malignant masses of the orbit include a large variety of neoplasms of epithelial or mesenchymal origin. The treatment of orbital malignancies is an essential interdisciplinary field of medicine that integrates ENT medicine, facial surgery, plastic surgery, neurosurgery, oncology and radiology.The main symptom of malignant orbital masses is the exophthalmos. A symptom that can help to differentiate a benign from a malignant orbital mass can be the pain. The main diagnostic tool is the MRI including new sequences like DWI and DCE.After presenting symptoms and diagnostic strategies of malignant orbital masses, this article starts with the description of malignant epithelial neoplasms of the lacrimal gland. Furthermore, it describes new insights in orbital lymphomas, followed by the discussion of semimalignant orbital masses. Last but not least the text deals with malignant neoplasms of the skin that can grow secondarily in the orbit. Finally, the manuscript discusses orbital metastases.

A review of solitary fibrous tumours of the orbit and ocular adnexa

Solitary fibrous tumour (SFT) is an uncommon spindle cell tumour of mesenchymal origin characterised by NAB2-STAT6 gene fusion. Although it was first described in the pleura, it can occur in connective tissue in any part of the body, but rarely presents in the orbit and ocular adnexa. SFT, which is part of the same disease spectrum as other fibroblastic tumours such as giant cell angiofibroma, haemangiopericytoma and fibrous histiocytoma, usually presents as a painless, slow-growing mass in any age group and generally follows a benign course, with a good prognosis after complete excision. However, malignant forms rarely occur. Even for benign tumours a more aggressive clinical behaviour is possible, with relentless infiltrative local growth, frequent recurrence following surgery, and malignant transformation with the potential for metastatic spread. Careful long-term follow-up is essential. The published literature on SFTs of the orbit and ocular adnexa is reviewed, and the aetiology, clinical presentation, epidemiology, radiological features, histopathology, immunohistochemistry, risk stratification, clinical management, and prognosis are discussed, reflecting on our own experience.

Clinical characteristics and treatment outcomes of secondary ocular adnexal lymphoma

BACKGROUND

To describe the clinical characteristics and treatment outcomes of secondary ocular adnexal lymphoma (OAL), and emphasise the impact of timely biopsy and systemic evaluation on the diagnosis and treatment.

METHODS

The data of patients with secondary OAL in our hospital from January 2010 to June 2021 were retrospectively reviewed.

RESULTS

A total of 54 patients (30 men and 24 women) were included in the study. The mean age at presentation was 60 years (median 62 years; range 37-83 years). The main symptoms included ocular mass (74%), periorbital swelling (43%), and proptosis (39%). The main histopathological types were mucosa-associated lymphoid tissue lymphoma (30%), diffuse large B-cell lymphoma (28%), and natural killer/T-cell lymphoma (18%). In particular, three patients exhibited different pathological types of ocular lymphoma compared to previously diagnosed systemic lymphoma. The most common site of ocular and systemic involvement was the orbit (85%) and lymph nodes (56%), respectively, and 25 (46%) patients had occult extraocular lesions. Additionally, the 5-year overall survival rate of the entire cohort was 56%, and significant differences were observed between the three main pathological types and stages of the disease (all p < 0.001).

CONCLUSIONS

Secondary OAL is a rare disease with a poor prognosis. That the disease is associated with a more aggressive pathological type is well established, indolent lymphoma is not uncommon. Furthermore, OAL and previously diagnosed systemic lymphoma may be pathologically distinct in some patients. Therefore, we recommend a prompt excision biopsy and a thorough systemic evaluation of patients with suspected OAL.

A clinicopathological reappraisal of orbital vascular malformations and distinctive GJA4 mutation in cavernous venous malformations

Vascular anomalies are common orbital lesions, while variations in previous nomenclature might hamper robust characterization of their clinicopathological and genetic features. We reviewed and reclassified 92 orbital vascular lesions by the modified International Society for the Study of Vascular Anomalies (ISSVA) classification with reappraising clinicopathological parameters of 4 main types of vascular malformations, including orbital venous malformation 1 (OVM1, cavernous venous malformation), OVM2 (varix), OVM3 (infiltrating venous malformation), and arteriovenous malformation (AVM). GJA4, BRAF, and KRAS mutations were assessed by Sanger sequencing. There were 90 cases of vascular malformations, consisting of 60 OVM1 (67%), 13 AVM (14%), 8 OVM2 (9%), 8 OVM3 (9%), and 1 lymphatic-venous malformation (1%). The prevailing OVM1, histologically characterized by well-delineated borders and a uniform cavernous growth pattern, predominantly occurred in intraconal space (57%, P = .019) with an older median age (49 years) and female predilection (73%). OVM2, OVM3, and AVM exhibited differences in the distributions of patients' ages and lesion locations. Sizes of lesions were significantly correlated with periorbital and intraconal/extraconal locations (P < .001). OVM1 had the lowest rate of residual and recurrent diseases (3%). GJA4 mutations were identified in 75% (44/59) of OVM1 but not in OVM2/3 and AVM. No BRAF or KRAS mutations were detected. In conclusion, the modified ISSVA scheme enables meaningful classification of orbital vascular malformations by highlighting the molecular correlation between the distinct clinicopathological features and specific GJA4 mutation in OVM1, which implies OVM1 as a unique variant of venous malformation genetically akin to cutaneous and hepatic counterparts.

Clinical heterogeneity between two subgroups of patients with idiopathic orbital inflammation

Objective

Idiopathic orbital inflammation (IOI) is a group of orbital inflammatory diseases of unknown etiopathogenesis. We investigated whether patients with IOI have clinical heterogeneity based on the presence (typical group) or absence (atypical group) of a unique onset that periocular inflammatory symptoms emerge suddenly but progress slowly.

Methods and analysis

This retrospective cohort study included 195 patients diagnosed with IOI. We analysed the clinical data of patients, including the outcomes of corticosteroid treatment, in two subgroups stratified on the basis of the presence (130 patients) or absence (65 patients) of the unique onset.

Results

Patients in the typical group were significantly younger at disease onset than those in the atypical group (median age; 52 vs 65 years, p=0.002); had more ocular adnexa-specific lesions, namely, dacryoadenitis, myositis, scleritis and optic perineuritis (78% vs 45%, p=0.00001); and had significantly fewer associations with immune-mediated inflammatory diseases (4% vs 15%, p=0.004). Among 30/119 patients (25%) who were steroid refractory in the typical group, a long period of time from symptom onset to initiation of treatment was a significant steroid-refractory risk factor (OR: 16.7), whereas, among the 18/40 patients (45%) who were steroid refractory in the atypical group, intraconal diffuse lesions were a significant steroid-refractory risk factor (OR: 8.8).

Conclusion

This cohort study suggests clinical heterogeneity between the two subgroups of patients with IOI.