Search

Abstract Background Nonpigmented malignant spindle cell tumours of the membrana nictitans are rare in dogs. In twenty-three years only three cases have been diagnosed in Scandinavia. This study describes the three cases of malignant tumours of the membrana nictitans recorded by the Eye Pathology Section, University of Copenhagen, Denmark, with reference to the clinical appearance and work-up, the treatment and prognosis, and the histopathological description including immunohistochemistry. The three cases are compared to previous publications on canine tumours of the nictitating membrane. We emphasize the importance of using protocols that are adapted to the specific species such as dogs. Opposite the human tissue responses, we even need more than one marker when diagnosing melanomas in dogs. Results The dogs presented were an 8-year-old Dachshund, a 12-year-old Akita and a 14-year-old Shetland Sheepdog. All three dogs were entire females. All three nictitating membrane tumours developed on the right nictitating membrane as firm or multilobulated hyperaemic masses. Two of the tumours were macroscopically nonpigmented, the third being partly pigmented on the surface and ulcerated. According to the histopathology and for two of the cases immunohistochemistry with dog-adapted protocols the diagnoses included one hemangiosarcoma and two amelanotic melanomas. Tumour regrowth developed in all three cases and repeated resections were completed 1, 2 and 3 times, respectively, with recurrence experienced within 1.5 months − 3 years. Conclusions Nonpigmented malignant spindle cell tumours of the canine membrana nictitans are rare. Treatment of choice should be complete excision with a minimal histologic tumour-free distance and in case of a recurrence a full resection of the nictitating membrane. We strongly recommend a dog-adapted protocol for immunohistochemistry.

Abstract Background Idiopathic intracranial hypertension (IIH) is a syndrome exhibiting elevated intracranial pressure (ICP), visual disturbances, and severe headache. IIH primarily affects young obese women, though it can occur in individuals of any age, BMI, and sex. IIH is characterized by systemic metabolic dysregulation with a profile of increased androgen hormones. However, the contribution of obesity/hormonal perturbations to cerebrospinal fluid (CSF) dynamics remains unresolved. Methods We employed obese female Zucker rats and adjuvant testosterone to reveal IIH causal drivers. ICP and CSF dynamics were determined with in vivo experimentation and magnetic resonance imaging, testosterone levels assessed with mass spectrometry, and choroid plexus function revealed with transcriptomics. Results Obese rats had undisturbed CSF testosterone levels and no changes in ICP or CSF dynamics. Adjuvant testosterone treatment of obese rats elevated the CSF secretion rate, although with no effect on the ICP, due to elevated CSF drainage capacity of these rats. Conclusions Obesity in itself therefore does not suffice to recapitulate the IIH symptoms in rats, but modulation of CSF dynamics appears with adjuvant testosterone treatment, which mimics the androgen excess observed in female IIH patients. Obesity-induced androgen dysregulation may thus contribute to the disease mechanism of IIH and could potentially serve as a future therapeutic target.

Introduction Sebaceous gland carcinoma (SGC) of the eyelid is an aggressive tumour with the ability to metastasise and an increased morbidity. Controversies regarding the epidemiology of this malignant eyelid tumour is widespread in the scientific literature. Western reports repeatedly describes eyelid SGC as a rare occurring tumour in general, accounting for 1%–3% of all eyelid tumours, however studies from Asia have uncovered a higher frequency of eyelid SGC including 54% of all eyelid tumours in Japan, and 43%–56% in India. We wish to retrieve observational data of eyelid SGC prevalence in proportion to total eyelid tumours, from pathological studies published worldwide to resolve this controversy.Methods and analysis We will search Ovid Medline, EMBASE, Cochrane Central Register of Controlled Trials, Scopus and Google Scholar to identify published reports on eyelid SGC prevalence proportions, aiming to clarify the incidence of the tumour. We will include observational clinicopathological studies reporting prevalence with confirmed histopathology. No limitations on publication date or language will be applied. Data from the individual studies and study quality will be extracted by two individual reviewers. Study quality will be assessed using the JBI Critical Appraisal Instrument for Studies Reporting Prevalence Data. Raw proportions will be transformed and pooled using a random effects model for meta-analysis. And subgroup analysis according to geography will be performed. If data are deemed unsuitable for a meta-analysis, a narrative synthesis will be presented. We will judge the certainty of evidence and present whether this has an overall effect on the results. The results may shed light on a long-standing academic disparity of the scientific literature.Ethics and dissemination This systematic review does not require ethical approval. The results of this proposed review will be the subject to a publication in an international peer-reviewed journal within the ophthalmic or pathological specialty.PROSPERO registration number CRD42023487141.

Plain Language Summary Vernal keratoconjunctivitis (VKC) is a rare, underdiagnosed, chronic allergic eye disease that typically occurs in children and adolescents. If left untreated, VKC can significantly damage the eye, potentially leading to long-term complications, visual impairment and a reduced quality of life for the child and their family and/or caregivers. In the absence of established guidelines, this consensus programme set out to gather expert insights on best practices for assessing and managing VKC across Europe. A group of seven European ophthalmologists engaged in the consensus programme. A total of 47 recommendations were developed relating to the assessment, diagnosis, management, referral and follow-up of patients with VKC. These 47 recommendations underwent two rounds of review and were revised, if necessary, following expert input. Recommendations where ≥ 75.0% of experts agreed were considered as having reached consensus and were included as final recommendations. The experts agreed that VKC can be classified as mild, moderate or severe, and should be managed according to severity in a stepwise manner, with treatment intensity escalating as the disease severity increases. Timely diagnosis and treatment initiation appropriate to the severity of VKC are crucial to prevent sight loss and improve the quality of life of children with VKC. Ongoing treatment may be necessary to tackle the chronic inflammation associated with the disease and, therefore, reliance on steroid eye drops should be reduced to avoid an increased risk of well-known complications. The experts concluded that mild VKC can be assessed and managed in primary care, but patients with severe VKC, or with moderate-to-severe VKC that does not respond to treatment within 2–4 weeks, should be referred to a VKC specialist.

To provide insights into targetable oncogenic pathways, this retrospective cohort study investigated the genetic profile of 26 patients with diffuse large B-cell lymphoma, not otherwise specified (DLBCL-NOS), and two patients with high-grade B-cell lymphoma with MYC and BCL2 rearrangements (HGBCL) presenting in the ocular adnexa. Pathogenic variants and copy number variations in 128 B-cell lymphoma-relevant genes were analyzed by targeted next-generation sequencing. Genetic subtypes were determined with the LymphGen algorithm. Primary ocular adnexal DLBCL-NOS constituted 50% (n = 14) and was generally characterized by non-germinal center B-cell origin (non-GCB) (n = 8, 57%), and LymphGen MCD subtype (n = 5, 36%). Primary ocular adnexal DLBCL-NOS presented pathogenic variants in genes involved in NF-κB activation and genes which are recurrently mutated in other extranodal lymphomas of non-GCB origin, including MYD88 (n = 4, 29%), CD79B (n = 3, 21%), PIM1 (n = 3, 21%), and TBL1XR1 (n = 3, 21%). Relapsed DLBCL-NOS presenting in the ocular adnexa (n = 6) were all of non-GCB origin and frequently of MCD subtype (n = 3, 50%), presenting with a similar genetic profile as primary ocular adnexal DLBCL-NOS. These results provide valuable insights into genetic drivers in ocular adnexal DLBCL-NOS, offering potential applications in future precision medicine.

Purpose: To present the clinical and histopathological characteristics of a rare case of ductal carcinoma in situ ex pleomorphic adenoma in the lacrimal gland. Observations: A 73-years-old Caucasian female presented with complaints of double vision and pain in the left eye region. Clinical examination revealed ptosis and exophthalmos of the left eye as well as diplopia on downward gaze. Magnetic resonance imaging of the left orbit demonstrated a 17 × 22 mm homogeneous tumor in the left lacrimal fossa. The tumor was excised in toto. Histopathological examination revealed a pleomorphic adenoma with ductal structures with benign looking epithelial cells, surrounded by myoepithelial cells. Tumor areas with cribriform architecture consisting of ductal structures with abnormal luminal epithelial cells and intact myoepithelial cell layer were also present. The surgical margins were clear. All luminal and myoepithelial cells were positive for cytokeratin 7, the luminal cells in the cribriform areas were positive for human epidermal growth factor 2 and androgen receptor. The myoepithelial cells were positive for cytokeratin 5, calponin and focally for glial fibrillar acid protein. The findings were diagnostic for ductal carcinoma in situ ex pleomorphic adenoma. Next generation sequencing Oncomine Comprehensive Assay mutation analysis found mutations in the BRCA2 (p.K3326*), BAP1 (p.S395*), and TP53 (p.E285K) genes in the ductal carcinoma in situ and BRCA2 (p.C9976A) in the pleomorphic adenoma part. Conclusion and importance: To our knowledge, this tumor is only the second described ductal carcinoma in situ ex pleomorphic adenoma of the lacrimal gland.

Purpose: To evaluate the proliferative diabetic retinopathy (PDR) progression rates and identify the demographic and clinical characteristics of patients who later developed PDR compared with patients who did not progress to that state. Design: A national 5-year register-based cohort study including 201 945 patients with diabetes. Subjects: Patients with diabetes who had attended the Danish national screening program (2013–2018) for diabetic retinopathy (DR). Methods: We used the first screening episode as the index date and included both eyes of patients with and without subsequent progression of PDR. Data were linked with various national health registries to investigate relevant clinical and demographic parameters. The International Clinical Retinopathy Disease Scale was used to classify DR, with no DR as level 0, mild DR as level 1, moderate DR as level 2, severe DR as level 3, and PDR as level 4. Main Outcome Measures: Hazard ratios (HRs) for incident PDR for all relevant demographic and clinical parameters and 1-, 3-, and 5-year incidence rates of PDR according to baseline DR level. Results: Progression to PDR within 5 years was identified in 2384 eyes of 1780 patients. Proliferative diabetic retinopathy progression rates from baseline DR level 3 at 1, 3 and 5 years were 3.6%, 10.9%, and 14.7%, respectively. The median number of visits was 3 (interquartile range, 1–4). Progression to PDR was predicted in a multivariable model by duration of diabetes (HR, 4.66 per 10 years; 95% confidence interval [CI], 4.05–5.37), type 1 diabetes (HR, 9.61; 95% CI, 8.01–11.53), a Charlson Comorbidity Index score of > 0 (score 1: HR, 4.62; 95% CI, 4.14–5.15; score 2: HR, 2.28; 95% CI, 1.90–2.74; score ≥ 3: HR, 4.28; 95% CI, 3.54–5.17), use of insulin (HR, 5.33; 95% CI, 4.49–6.33), and use of antihypertensive medications (HR, 2.23; 95% CI, 1.90–2.61). Conclusions: In a 5-year longitudinal study of an entire screening nation, we found increased risk of PDR with increasing baseline DR levels, longer duration of diabetes, type 1 diabetes, systemic comorbidity, use of insulin, and blood pressure–lowering medications. Most interestingly, we found lower risk of progression from DR level 3 to PDR compared with that in previous studies. Financial Disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Abstract Migraine is a disease characterized by cerebral vasodilation. While diabetes has previously been associated with a lower risk of migraine, it is not known if diabetic retinopathy (DR), a retinal peripheral vascular occlusive disease, is a potential biomarker of protection against migraine. Therefore, we aimed to examine diabetic retinopathy as a marker of prevalent and 5-year incident migraine. In a national cohort, we compared patients with diabetes attending DR screening from The Danish National Registry of Diabetic Retinopathy (cases, n = 205,970) to an age- and gender-matched group of patients without diabetes (controls, n = 1,003,170). In the cross-sectional study, a multivariable model demonstrated a lower prevalence of migraine among cases compared with controls (OR 0.83, 95% CI 0.81–0.85), with a lower risk in cases with DR than in those without (OR 0.69, 95% CI 0.65–0.72). In the prospective study, a lower risk of incident migraine was found in a multivariable model in cases (HR 0.76, 95% CI 0.70–0.82), but this did not depend upon the presence of DR. To conclude, in a national study of more than 1.2 million people, patients screened for DR had a lower risk of present migraine, but DR was not a protective marker of incident migraine.

Purpose: Diabetic retinopathy (DR) is a hypoxic retinal disease, but so far, the association with systemic hypoxia is poorly understood. Hence, the aim of this study was to evaluate cross-sectional and longitudinal associations between DR and chronic respiratory failure (CRF) in a national cohort. Design: Cross-sectional and 5-year longitudinal register-based cohort study. Methods: Between 2013 and 2018, we included patients with diabetes from the Danish Registry of Diabetic Retinopathy, who were each age and sex matched with five controls without diabetes. At index date, the prevalence of CRF was compared between cases and controls, and the longitudinal relationship between DR and CRF was assessed in a five-year follow-up. Results: At baseline, we identified 1,980 and 9,990 patients with CRF among 205,970 cases and 1,003,170 controls. The prevalence of CRF was higher among cases than controls (OR 1.75, 95% CI 1.65–1.86), but no difference between cases with and without DR was found.During follow-up, we identified 1,726 and 5,177 events of CRF among cases and controls, respectively. The incidence of CRF was higher among both cases with and without DR compared to controls (DR level 0: HR 1.24, 95% CI 1.16–1.33, DR level 1–4: HR 1.86, 95% CI 1.63–2.12), and higher among cases with DR compared to cases without DR (HR 1.54, 95% CI 1.38–1.72). Conclusion: In this study based on nationwide data, we found an increased risk of present and incident CRF in patients with diabetes with or without DR, and we identified DR as a predictor of future CRF.

Raptor, a key component of mTORC1, is required for recruiting substrates to mTORC1 and contributing to its subcellular localization. Raptor has a highly conserved N-terminus domain and seven WD40 repeats, which interact with mTOR and other mTORC1-related proteins. mTORC1 participates in various cellular events and mediates differentiation and metabolism. Directly or indirectly, many factors mediate the differentiation and function of lymphocytes that is essential for immunity. In this review, we summarize the role of Raptor in lymphocytes differentiation and function, whereby Raptor mediates the secretion of cytokines to induce early lymphocyte metabolism, development, proliferation and migration. Additionally, Raptor regulates the function of lymphocytes by regulating their steady-state maintenance and activation.

In order to support or refute the clinical suspicion of cranial giant cell arteritis (GCA), a supplemental imaging modality is often required. High-resolution black blood Magnetic Resonance Imaging (BB MRI) techniques with contrast enhancement can visualize artery wall inflammation in GCA. We compared findings on BB MRI without contrast enhancement with findings on 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/low-dose computed tomography (2-[18F]FDG PET/CT) in ten patients suspected of having GCA and in five control subjects who had a 2-[18F]FDG PET/CT performed as a routine control for malignant melanoma. BB MRI was consistent with 2-[18F]FDG PET/CT in 10 out of 10 cases in the group with suspected GCA. In four out of five cases in the control group, the BB MRI was consistent with 2-[18F]FDG PET/CT. In this small population, BB MRI without contrast enhancement shows promising performance in the diagnosis of GCA, and might be an applicable imaging modality in patients.

Introduction: we investigated the association between OSA and vision-threatening diabetic retinopathy (VTDR). Methods: we used three nationwide registers to identify subjects with and without OSA and patients with type 1 (T1DM) or type 2 diabetes mellitus (T2DM). The Danish Civil Registration System was used to link OSA with diabetes diagnosis. The primary outcome was the occurrence of VTDR in diabetic patients with and without OSA. The secondary outcome was the prevalence of diabetes mellitus in patients with and without OSA. Results: we included 532,828 diabetic subjects comprising 13,279 patients with OSA (2.5%) and 519,549 without OSA (97.5%). Diabetic patients with OSA had a 57% lower risk of VTDR compared to diabetic patients without OSA (OR 0.43, 95% CI 0.38–0.50, p < 0.0001). Conclusions: our findings indicate that OSA is associated with a lower risk of VTDR. Since we did not adjust our outcomes for diabetes duration, hypertension control and hemoglobin A1c, future studies are needed to confirm our findings.

Meibomian gland dysfunction (MGD) is a highly prevalent condition and the most common cause of evaporative dry eye disease. Studying the proteome of MGD can result in important advances in the management of the condition. Here, we collected tear film samples from treatment naïve patients with MGD (n = 10) and age-matched controls (n = 11) with Schirmer filtration paper. The samples were analyzed with label-free quantification nano liquid chromatography—tandem mass spectrometry. The proteins were considered differentially expressed if p < 0.05. A total of 88 proteins were significantly regulated. The largest change was observed in cystatin-SN, which was downregulated in MGD and correlated negatively with tear meniscus height. The downregulation of cystatin-SN was confirmed with targeted mass spectrometry by single reaction monitoring (SRM). Eighteen immunoglobulin components involved in B cell activation, phagocytosis, and complement activation were downregulated in MGD including Ig alpha-1 chain C region, immunoglobulin J chain, immunoglobulin heavy variable 3–15, and Ig mu chain C region. The changes in cystatin-SN and immunoglobulin chains are likely to result from the inflammatory changes related to tear film evaporation, and future studies may assess their association with the meibum quality.

Introduction: Most intraocular pressure (IOP)-lowering eye drops are preserved with benzalkonium chloride (BAK). This can increase side effects and decrease adherence. Particularly, damage to the mucin-producing conjunctival goblet cells may be an issue due to instability of the tear film. We aimed to investigate the effect of IOP-lowering eye drops preserved with BAK on cultured human conjunctival goblet cells. Methods: Eye drops Brimonidine Tartrate Teva (BT) with 0.005% BAK, Dorzolamide Stada (DS) with 0.0075% BAK, Optimol® (OP) with 0.01% BAK, and Latanoprost Teva (LT) with 0.02% BAK were included. Human primary cultured goblet cell survival was evaluated using a lactate dehydrogenase assay on human goblet cells after treatment for 30 min and 6 h with the different anti-glaucoma drug formulations. Results: All eye drops examined, except BT, reduced goblet cell survival. The impact of eye drops on goblet cell viability was correlated with the time of exposure as well as to the concentration of BAK. After 30 min of exposure, cell viability was 93% for BT (0.005% BAK; p = 0.93), 71% for DS (0.0075% BAK; p = 0.067), 70% for OP (0.01% BAK; p = 0.054), and 69% for LT (0.02% BAK; p = 0.022), and exposure for 6 h reduced cell survival to 74% for BT (p = 0.217), 52% for DS (p = 0.011), 34% for OP (p = 0.017), and 31% for LT (p = 0.0007). Conclusion: LT, OP, and DS reduced human goblet cell survival in a time-dependent manner. BT did not affect goblet cell survival. Cell survival was correlated with the BAK concentration in the eye drops making 0.02% BAK-preserved LT most toxic and 0.005% BAK-preserved BT least toxic. Based on the present study, decreasing BAK in eye drops for chronic use seems important to reduce damage to the goblet cells. However, future studies are needed to further explore this finding.

Chondromyxoid fibroma (CMF) is a very rare entity, accounting for

Abstract Background Visible light, predominantly in the blue range, affects mood and circadian rhythm partly by activation of the melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs). The light-induced responses of these ganglion cells can be evaluated by pupillometry. The study aimed to assess the blue light induced pupil constriction in patients with bipolar disorder (BD). Methods We investigated the pupillary responses to blue light by chromatic pupillometry in 31 patients with newly diagnosed bipolar disorder, 22 of their unaffected relatives and 35 healthy controls. Mood state was evaluated by interview-based ratings of depressive symptoms (Hamilton Depression Rating Scale) and (hypo-)manic symptoms (Young Mania Rating Scale). Results The ipRGC-mediated pupillary responses did not differ across the three groups, but subgroup analyses showed that patients in remission had reduced ipRGC-mediated responses compared with controls (9%, p = 0.04). Longer illness duration was associated with more pronounced ipRGC-responses (7% increase/10-year illness duration, p = 0.02). Conclusions The ipRGC-mediated pupil response to blue light was reduced in euthymic patients compared with controls and increased with longer disease duration. Longitudinal studies are needed to corroborate these potential associations with illness state and/or progression.

Mucosal melanomas are not thought to be UV radiation (UVR)-driven, yet some present UVR-related mutations. Here the authors show that some mucosal melanomas, especially conjunctival, present mutations characteristic of UVR exposure, yet share structural variants typical of other mucosal melanomas.

Giant cell arteritis (GCA) is an ophthalmological emergency that can be difficult to diagnose and prompt treatment is vital. We investigated the sequential diagnostic value for patients with suspected GCA using three biochemical measures as they arrive to the clinician: first, platelet count, then C-reactive protein (CRP), and lastly, erythrocyte sedimentation rate (ESR). This retrospective cross-sectional study of consecutive patients with suspected GCA investigated platelet count, CRP, and ESR using diagnostic test accuracy statistics and odds ratios (ORs) in a sequential fashion. The diagnosis was established by experts at follow-up, considering clinical findings and tests including temporal artery biopsy. A total of 94 patients were included, of which 37 (40%) were diagnosed with GCA. Compared with those without GCA, patients with GCA had a higher platelet count (p < 0.001), CRP (p < 0.001), and ESR (p < 0.001). Platelet count demonstrated a low sensitivity (38%) and high specificity (88%); CRP, a high sensitivity (86%) and low specificity (56%); routine ESR, a high sensitivity (89%) and low specificity (47%); and age-adjusted ESR, a moderate sensitivity (65%) and moderate specificity (65%). Sequential analysis revealed that ESR did not provide additional value in evaluating risk of GCA. Initial biochemical evaluation can be based on platelet count and CRP, without waiting for ESR, which allows faster initial decision-making in GCA.

Adenoid cystic carcinoma (ACC) is an aggressive malignancy that most often arises in salivary or lacrimal glands but can also occur in other tissues. We used optimized RNA-sequencing to analyze the transcriptomes of 113 ACC tumor samples from salivary gland, lacrimal gland, breast or skin. ACC tumors from different organs displayed remarkedly similar transcription profiles, and most harbored translocations in the MYB or MYBL1 genes, which encode oncogenic transcription factors that may induce dramatic genetic and epigenetic changes leading to a dominant ‘ACC phenotype’. Further analysis of the 56 salivary gland ACC tumors led to the identification of three distinct groups of patients, based on gene expression profiles, including one group with worse survival. We tested whether this new cohort could be used to validate a biomarker developed previously with a different set of 68 ACC tumor samples. Indeed, a 49-gene classifier developed with the earlier cohort correctly identified 98% of the poor survival patients from the new set, and a 14-gene classifier was almost as accurate. These validated biomarkers form a platform to identify and stratify high-risk ACC patients into clinical trials of targeted therapies for sustained clinical response.

Abstract The clinical course of trilateral retinoblastoma can be unpredictable, and expressivity of germline RB1 variants may vary during development. We describe an unexpected fatal case of trilateral retinoblastoma with an intracranial tumor in an unusual location and discuss genetic copy number analyses as a useful diagnostic tool with therapeutic potential.

Purpose: Rhino-orbital-cerebral mucormycosis (ROCM) is a rare opportunistic infection with a high mortality despite relevant treatment. Observations: A 3-year-old girl under treatment for acute lymphoblastic leukemia developed periorbital swelling, ophthalmoplegia and a necrotic palatal lesion during a period of neutropenia. Imaging revealed sinusitis, pre- and postseptal cellulitis. The disease later progressed to cerebral involvement and orbital apex syndrome with complete ophthalmoplegia, ptosis and loss of vision. The patient was treated with systemic antifungal therapy, hyperbaric oxygen and extensive surgery. This included orbital exenteration, skull base resection, cerebral debridement with placement of an Ommaya reservoir for intrathecal administrations of amphotericin B (AmB) and in addition endoscopic sinus surgery with local AmB installation. Chemotherapy was safely continued after resolution of the ROCM and the patient remains in complete remission after 5 years. Conclusion and importance: Patients with ROCM can be cured with aggressive multimodality treatment, including surgical intervention, even if in myelosuppression.

Background: In the head and neck region the uvula is a rare site for extranodal lymphomas to develop. In this national study, we present six cases and provide an overview of the current literature, characterizing the clinical and histopathological features of lymphomas involving this location.Materials and Methods: Clinical information was obtained retrospectively from patient records in a nationwide Danish study covering from 1980 through 2019. In order to validate the diagnoses, uvular tissue specimens were examined histologically and immunohistochemically and if relevant for subtyping, cytogenetic rearrangements were investigated.Results: We present six cases of lymphomas involving the uvula, of which four of the cases were diagnosed with a B-cell lymphoma (two diffuse large B-cell lymphomas, one extranodal marginal zone B-cell lymphoma and one Mantle cell lymphoma), while two were diagnosed with a T-cell lymphoma (one peripheral T-cell lymphoma and one natural killer/T-cell lymphoma). Presenting symptoms included swelling, pain and ulceration of the uvula. Treatment was comprised of radiotherapy and/or chemotherapy, with T-cell lymphomas showing a poorer outcome than B-cell lymphomas.Conclusion: Lymphoma of the uvula is rare, with few case reports being reported in the literature. The most frequent histological subtypes reported are extranodal marginal zone B-cell lymphoma and peripheral T-cell lymphoma. When encountering a swollen, painful and/or ulcerated uvula, the clinician should always consider malignancy as a possible cause. Lymphoma of the uvula is a possible diagnosis and if this is the case, there is a high risk of disseminated disease at the time of diagnosis.

The pathogenesis of squamous cell neoplasms arising in the lacrimal drainage system is poorly understood, and the underlying genomic drivers for disease development remain unexplored. We aimed to investigate the genomic aberrations in carcinomas arising in the LDS and correlate the findings to human papillomavirus (HPV) status. The HPV analysis was performed using HPV DNA PCR, HPV E6/E7 mRNA in-situ hybridization, and p16 immunohistochemistry. The genomic characterization was performed by targeted DNA sequencing of 523 cancer-relevant genes. Patients with LDS papilloma (n = 17) and LDS carcinoma (n = 15) were included. There was a male predominance (68%) and a median age at diagnosis of 46.0 years (range 27.5–65.5 years) in patients with papilloma and 63.8 years (range 34.0–87.2 years) in patients with carcinoma. Transcriptional activity of the HPV E6/E7 oncogenes was detected in the whole tumor thickness in 12/15 (80%) papillomas (HPV6, 11, 16) and 10/15 (67%) squamous cell carcinomas (SCC) (HPV11: 3/15 (20%) and HPV16: 7/15 (47%)). Pathogenic variants in PIK3CA, FGFR3, AKT1, and PIK3R1, wildtype TP53, p16 overexpression, and deregulated high-risk E6/E7 transcription characterized the HPV16-positive SCC. The deregulated pattern of HPV E6/E7 expression, correlating with HPV DNA presence and p16 positivity, supports a causal role of HPV in a subset of LDS papillomas and carcinomas. The viral and molecular profile of LDS SCC resembles that of other HPV-driven SCC.

Purpose: To examine the physicochemical properties of five preservative-free (PF) 0.005% latanoprost ophthalmic products; Monoprost®, Latanest®, Gaap Ofteno®, Xalmono®, and Xaloptic® Free. Furthermore, the study investigated the mucin production and cell survival of primary cultured human conjunctival goblet cells when treated with PF eye drops. Method: The pH value, osmolality, and surface tension were examined. Cell survival was analyzed using lactate dehydrogenase and tetrazolium dye colorimetric assays. Mucin production was analyzed with immunohistochemical staining. Results: Monoprost® (pH value 6.84 ± 0.032) had a pH value closest to the pH value of tear fluid (pH value 7.4–7.6), whereas Gaap Ofteno® (pH value 6.34 ± 0.004) and Latanest® (pH value 6.33 ± 0.003) had the lowest pH values. Gaap Ofteno® (325.9 ± 2.9 mosmol/kg) showed iso-osmolar probabilities, whereas the other products were hypo-osmolar. Gaap Ofteno® (60.31 ± 0.35 mN/m) had a higher surface tension compared to the tear fluid (40 to 46 mN/m), as described in the literature. No significant differences in goblet cell survival or mucin release were observed between the treatments and control. Conclusion: Significant differences in pH value, osmolality, and surface tension were observed. However, this did not affect the viability of the goblet cells or the release of mucin. Clinical studies are required to evaluate the long-term effects of use on efficacy and safety.

Abstract Background Eyelid tumours are frequently found in dogs, most of these being benign. In case of an ulcerating eyelid tumour, malignancy must be considered. We report a unique case of a low-grade peripheral T-cell lymphoma in the eyelid of a 9-year-old English Setter. Case presentation A 9-year-old Setter presented with a 6-month history of an eyelid ulcer. A malignant eyelid neoplasm was suspected, and the lesion was surgically excised. No other treatment was applied, and 19 months after excision the dog was still well. Histopathology revealed a diffuse lymphocytic infiltrate in the eyelid skin. Ulceration of the epithelium was seen, and the underlying tumour was composed of round and poorly demarcated pleomorphic tumour cells. The cytoplasm was pale and the nuclei heterogeneous. Numerous mitoses were present. The tumour cells stained strongly for CD3. The final diagnosis was a peripheral T-cell lymphoma not otherwise specified (NOS). Conclusions This is the first described case of a solitary T-cell lymphoma NOS in the haired eyelid skin in a dog. Lymphoma should be considered in case of a persistent eyelid ulcer and a biopsy should be performed. T-cell lymphoma is generally an aggressive disease; however, indolent cases are well known, and as this case shows, complete excision of a solitary T-cell lymphoma can be curable. Canine cutaneous epitheliotropic T-cell lymphoma is an important differential diagnosis, which must be recognized as the prognosis is very poor and systemic treatment is mandatory. The sub-classification of canine lymphoma is not complete, and further studies are needed to identify lymphoma subgroups and provide treatment guidelines.

Purpose: In previous smaller studies, associations were demonstrated between diabetic retinopathy (DR) and obstructive sleep apnea (OSA), but longitudinal relationships have not been evaluated in larger cohorts. The aim of the present study was to assess the cross-sectional and prospective associations between DR and OSA in a national cohort of patients with type 2 diabetes. Design: Cross-sectional and 5-year longitudinal registry-based cohort study. Participants: For cases, we included 153 238 patients with type 2 diabetes who had attended diabetic eye screening and were registered in the Danish Registry of Diabetic Retinopathy (DiaBase). Each of these were matched by 5 control participants without diabetes of the same age and gender (n = 746 148). Methods: Exposure and outcome data as well as systemic morbidity and use of medications were identified in national registers, including the DiaBase, the Danish National Patient Register, the Danish National Prescription Registry, and the Danish Civil Registration System. The index date was defined as the date of the first DR screening registered in DiaBase. Main Outcome Measures: Exposure was defined as present and level-specific DR, and main outcomes were crude, age- and gender-adjusted, and multivariable adjusted odds ratios (ORs) for prevalent OSA as well as hazard ratios (HR) for 5-year incident OSA and DR. Results: Patients with type 2 diabetes independently were more likely to have prevalent OSA (OR, 2.01; 95% confidence interval [CI], 1.95–2.08) and to develop OSA within 5 years (HR, 1.55; 95% CI, 1.46–1.64). Patients with type 2 diabetes and DR at baseline were less likely to have prevalent OSA (OR, 0.57; 95% CI, 0.52–0.62) or to demonstrate incident OSA (HR, 0.86; 95% CI, 0.74–0.99). Likewise, patients with OSA had a lower risk to develop DR (HR, 0.83; 95% CI, 0.74–0.92). Conclusions: In a registry-based national cohort study, patients with type 2 diabetes had a higher risk of OSA. However, a 43% decreased risk of prevalent OSA was demonstrated in patients with DR, and prospectively, OSA and DR both were related inversely with each other.

Background: Lymphoma of the sublingual gland is rare, representing 1% of all salivary gland lymphomas. In this case report, we present three new cases and compare them to previously published cases, with the aim of characterizing the clinical, morphological, histopathological, and genetic features of this type of malignancy.Materials and Methods: We provide a clinical description of three cases along with a characterization of the microscopic features, including morphology, and immunohistochemistry. In addition, we analysed possible cytogenetic rearrangements with the use of fluorescence in situ hybridization (FISH).Results: Case 1: A 61-year-old male presenting with a painless swelling of the floor of the mouth diagnosed as extranodal marginal zone lymphoma (EMZL) of the left sublingual gland. The patient is alive with no evidence of disease after his fourth treatment regimen following several relapses. Case 2: A 68-year-old female with a prior history of mantle cell lymphoma (MCL) presenting with a tender swelling of the left sublingual gland as well as the right submandibular gland. The lesions were diagnosed as relapsing MCL. The patient died of unrelated causes after 18 months of treatment. Case 3: A 75-year-old female presenting with a swelling of the floor of the mouth diagnosed as follicular lymphoma (FL) of the left sublingual gland. The patient received chemotherapy along with radiotherapy and was still alive 10 years after the diagnosis.Conclusion: The three cases of sublingual gland lymphomas presented in this case report resemble lymphomas of other major salivary glands. The clinician should be aware of this type of malignancy and that the clinical presentation may not differ from benign lesions or other more common malignancies in this location.

Background: Studies on the risk of new primary cancer in patients with posterior uveal melanoma (UM) have produced conflicting results, and the role of socioeconomic status (SES) is unknown. The purpose of this population-based matched cohort study was to determine the risk of new primary cancer following the diagnosis of posterior UM. Methods: 2179 patients with posterior UM 1968–2016 and 22,717 matched controls without cancer were included. Incidence and time-dependent hazard ratio (HR) of new primary cancer were described, and the effect of SES was emphasized in a sub-cohort. Results: The incidence of new primary cancer was increased in patients with posterior UM, rate ratio (RR) 1.21 (95% CI: 1.08; 1.35), but the specific cancer types did not differ compared to the controls. The rate of new primary cancer following the diagnosis of posterior UM was significantly increased 2–5 years (HR 1.49 (95% CI: 1.23; 1.80)) and 11–15 years (HR: 1.49 (95% CI: 1.12; 1.99)), and adjusting for SES did not change the rate (HR 1.35 (95% CI:1.20; 1.55)). Conclusions: Patients with posterior UM have an increased risk of new primary cancer independent of SES. No difference in incidence of specific cancer type was observed compared to the control group.

There is a need for unified guidance on the management of ocular manifestations of atopic dermatitis and ocular manifestations associated with dupilumab in the Nordic region (Denmark, Finland, Norway and Sweden). This initiative gathered Nordic dermatologists and ophthalmologists to identify consensus in this area using a modified Delphi process. The initiative was led by a Nordic expert panel who developed a questionnaire that was circulated to a wider group. The results informed an agenda consisting of 24 statements to be voted on using a 5-point Likert scale at a meeting in Copenhagen on 24 April 2019. A facilitator moderated discussion and revised statements according to expert feedback for a second vote when required to reach consensus. Consensus was reached for 23 statements regarding the diagnosis, treatment and referral of these patients, which we hope will improve patient management in the Nordic region.

Purpose: To describe a case of Waldenström's macroglobulinemia/lymphoplasmacytic lymphoma with infiltration of both lacrimal glands. Observations: A 63-year-old male with Waldenström's macroglobulinemia was referred to the ophthalmological clinic due to intermittent bilateral painless swollen eyelids. The patient had slight bilateral chemosis along with swelling of both eyelids. A mechanical ptosis was present on both sides. Funduscopic examination and tonometry were normal. Computed tomography and positron emission tomography showed an enlargement of both lacrimal glands with positive PET signal, and hence a biopsy was performed for histological and cytogenetic examination. Histopathological examination revealed an infiltrate of lymphoplasmacytic cells and small lymphocytes within the lacrimal gland. The tumor cells stained positive for IgM and CD20, CD79, BCL-2, and kappa light chain. A cytogenetic examination revealed a mutation in MYD88 confirming Morbus Waldenström/lymphoplasmacytic lymphoma. Conclusions and importance: Intermittent swollen lacrimal glands are a rather common symptom, and Morbus Waldenström/lymphoplasmacytic lymphoma should be considered as a differential diagnosis. This symptom should be carefully evaluated in Waldenström patients, as it can be a sign of disease progression in case of lacrimal gland involvement. Keywords: Lymphoplasmacytic lymphoma, Lymphoma, Waldenström macroglobulinaemia, Bilateral, Lacrimal gland

Human papillomaviruses (HPV) are a large group of DNA viruses that infect the basal cells of the stratified epithelium at different anatomic locations. In the ocular adnexal region, the mucosa of the conjunctiva and the lacrimal drainage system, as well as the eyelid skin, are potential locations for HPV-related neoplasia. The role of HPV in squamous cell neoplasia of the ocular adnexa has been debated for several decades. Due to the rarity of all these tumors, large studies are not available in the scientific literature, thereby hampering the precision of the HPV prevalence estimates and the ability to conclude. Nevertheless, increasing evidence supports that defined subsets of conjunctival papillomas, intraepithelial neoplasia, and carcinomas develop in an HPV-dependent pathway. The role of HPV in squamous cell tumors arising in the lacrimal drainage system and the eyelid is still uncertain. Further, the potential of HPV status as a diagnostic, prognostic, or predictive biomarker in these diseases is a topic for future research.

Our objectives were to investigate whether the conjunctival microbiota is altered by contact lens wear and/or bacterial keratitis and to explore the hypothesis that commensals of conjunctival microbiota contribute to bacterial keratitis. Swab samples from both eyes were collected separately from the inferior fornix of the conjunctiva of non-contact-lens users (nparticipants = 28) and contact lens users (nparticipants = 26) and from patients with contact-lens-associated bacterial keratitis (nparticipants = 9). DNA from conjunctival swab samples was analyzed with 16S rRNA gene amplicon sequencing. Pathogens from the corneal infiltrates were identified by cultivation. In total, we identified 19 phyla and 283 genera; the four most abundant genera were Pseudomonas, Enhydrobacter, Staphylococcus, and Cutibacterium. Several pathogens related to bacterial keratitis were identified in the conjunctival microbiota of the whole study population, and the same bacteria were identified by both methods in the conjunctiva and cornea for four patients with contact-lens-associated bacterial keratitis. The overall conjunctival microbiota profile was not altered by contact lens wear or bacterial keratitis; thus, it does not appear to contribute to the development of bacterial keratitis in contact lens users. However, in some individuals, conjunctival microbiota may harbor opportunistic pathogens causing contact-lens-associated bacterial keratitis.

Abstract Background Covering the eye of all snakes is a transparent integumental structure known as the spectacle. In order to determine variations in spectacle thickness among species, the spectacles of 217 alcohol-preserved museum specimens of 44 species belonging to 14 different families underwent optical coherence tomography (OCT) to measure spectacular thickness. Multivariable analyses were made to determine whether family, activity period (diurnal/nocturnal) and habitat (arboreal/terrestrial/fossorial/aquatic) influenced spectacle thickness. Results The thinnest spectacles in absolute terms were found in the Usambara bush viper (Viperidae) with a thickness of 74 ± 9 μm and the absolute thickest spectacle was found in the red-tailed pipe snake (Cylindrophiidae) which had a spectacle thickness of 244 ± 57 μm. Fossorial and aquatic snakes had significantly thicker spectacles than arboreal and terrestrial snakes. When spectacle thickness was correlated to eye size (horizontal spectacle diameter), Gray’s earth snake (Uropeltidae) had the lowest ratio (1:7) and the cottonmouth (Viperidae) had the highest ratio (1:65). Multivariable and phylogenetic analyses showed that spectacular thickness could be predicted by taxonomic family and habitat, but not activity period. Conclusion This phylogenetically broad systematic study of the thickness of the snake spectacle showed that spectacular thickness varies greatly across snake species and may reflect evolutionary adaptation and development.

Abstract Background Surveillance for bovine genetic diseases in Denmark identified a hitherto unreported congenital syndrome occurring among progeny of a Holstein sire used for artificial breeding. A genetic aetiology due to a dominant inheritance with incomplete penetrance or a mosaic germline mutation was suspected as all recorded cases were progeny of the same sire. Detailed investigations were performed to characterize the syndrome and to reveal its cause. Results Seven malformed calves were submitted examination. All cases shared a common morphology with the most striking lesions being severe facial dysplasia and complete prolapse of the eyes. Consequently the syndrome was named facial dysplasia syndrome (FDS). Furthermore, extensive brain malformations, including microencephaly, hydrocephalus, lobation of the cerebral hemispheres and compression of the brain were present. Subsequent data analysis of progeny of the sire revealed that around 0.5% of his offspring suffered from FDS. High density single nucleotide polymorphism (SNP) genotyping data of the seven cases and their parents were used to map the defect in the bovine genome. Significant genetic linkage was obtained for three regions, including chromosome 26 where whole genome sequencing of a case-parent trio revealed two de novo variants perfectly associated with the disease: an intronic SNP in the DMBT1 gene and a single non-synonymous variant in the FGFR2 gene. This FGFR2 missense variant (c.927G>T) affects a gene encoding a member of the fibroblast growth factor receptor family, where amino acid sequence is highly conserved between members and across species. It is predicted to change an evolutionary conserved tryptophan into a cysteine residue (p.Trp309Cys). Both variant alleles were proven to result from de novo mutation events in the germline of the sire. Conclusions FDS is a novel genetic disorder of Holstein cattle. Mutations in the human FGFR2 gene are associated with various dominant inherited craniofacial dysostosis syndromes. Given the phenotypic similarities in FDS affected calves, the genetic mapping and absence of further high impact variants in the critical genome regions, it is highly likely that the missense mutation in the FGFR2 gene caused the FDS phenotype in a dominant mode of inheritance.

Epidermal filaggrin level is affected by ultraviolet B irradiation in animal and experimental models. This study examined the effect of ultraviolet B irradiation on epidermal filaggrin and natural moisturizing factors in vivo in healthy adults (n = 22). Participants were irradiated with 2 minimal erythema doses of ultraviolet B on the skin. Biopsies and tape strips were collected from skin irradiated 24 and 72 h earlier and from non-irradiated skin (control). Real-time quantitative PCR on skin biopsies showed significantly reduced profilaggrin mRNA expression 24 h after irradiation (mean relative mRNA expression ± standard deviation: control, 3.86 ± 2.06 vs. 24 h, 1.52 ± 0.640; p = 0.02; n = 8). Immunohistochemistry showed aberrant spatial distribution of filaggrin protein 72 h after irradiation (n = 3). High-pressure liquid chromatography of tape extracts showed no change in mean total natural moisturizing factor levels after irradiation, but mean trans-urocanic acid was significantly reduced, as expected (n = 8). In conclusion, erythemal doses of ultraviolet B exert acute effects on profilaggrin mRNA and filaggrin protein in human skin in vivo.

Background: To present a rare case of a 2-year-old girl with neurofibromatosis type 1 (NF1) who presented with ptosis of the right upper eyelid along with a tumor in the eyelid. Methods: A magnetic resonance imaging scan of the orbit revealed a solid tumor located extraconally at the site of the right lacrimal gland. A transcranial orbitotomy was performed. Results: Histopathological examination demonstrated expanded nerve branches/fascicles cut in various planes in between normal lacrimal gland acini. These findings were consistent with a plexiform neurofibroma presumably deriving from the lacrimal nerve and/or a supraorbital nerve branch. Conclusion: This is the first case of a plexiform neurofibroma involving the lacrimal gland ever described and the tumor shows similarities with neurofibroma in other salivary glands with a high recurrence rate. Plexiform neurofibromas are frequently seen in patients with NF1 and rarely undergo malignant transformation.

This study reports findings from a 56-year-old patient, who had received bilateral intravitreal injection of putative adipose tissue-derived stem cells at a private clinic in India with the promise of treatment of NAION. During an observation period of 8, respectively, 18 months, the intravitreally injected cells remained silent in the vitreous bodies without either therapeutic effects or complications. The cells cleared with vitrectomy without evidence of integration in the optic nerve or retina. Contrary to recent reports on patients receiving intravitreal injections of similar putative stem cells with the aim of treating AMD, our patient suffered no devastating ocular consequences. Summary. Contrary to recent reports, this case demonstrated no devastating consequences of intravitreal injection of adipose tissue-derived stem cells during an observation period of up to 18 months. After vitrectomy, the cells cleared without evidence of either harm or integration.

Melanoma of the ocular region (ocular melanoma) comprises about 5% of all patients with melanoma and covers posterior uveal melanoma, iris melanoma, and conjunctival melanoma. The risk of metastasis is much higher in patients with ocular melanoma compared to a primary melanoma of the skin. The subtypes of ocular melanoma have distinct genetic features, which should be taken into consideration when making clinical decisions. Most relevant for current practice is the absence of BRAF mutations in posterior uveal melanoma, although present in some iris melanomas and conjunctival melanomas. In this review, we discuss the genetic biomarkers of the subtypes of ocular melanoma and their impacts on the clinical care of these patients.

Purpose: Introducing a simple image grading system to support the interpretation of in vivo confocal microscopy (IVCM) images in filamentous fungal keratitis. Setting: Clinical and confocal studies took place at the Department of Ophthalmology, Aarhus University Hospital, Denmark. Histopathological analysis was performed at the Eye Pathology Institute, Department of Neuroscience and Pharmacology, University of Copenhagen, Denmark. Methods: A recent series of consecutive patients with filamentous fungal keratitis is presented to demonstrate the results from in-house IVCM. Based upon our experience with IVCM and previously published images, we composed a grading system for interpreting IVCM images of filamentous fungal keratitis. Results: A recent case series of filamentous fungal keratitis from 2011 to 2012 was examined. There were 3 male and 3 female patients. Mean age was 44.5 years (range 12-69), 6 out of 17 (35%) cultures were positive and a total of 6/7 (86%) IVCM scans were positive. Three different categories of IVCM results for the grading of diagnostic certainty were formed. Conclusion: IVCM is a valuable tool for diagnosing filamentous fungal keratitis. In order to improve the reliability of IVCM, we suggest implementing a simple and clinically applicable grading system for aiding the interpretation of IVCM images of filamentous fungal keratitis.

Purpose: To report a case of progressive fibrotic contraction of the posterior lamellar graft after initially successful Descemet’s stripping automated endothelial keratoplasty (DSAEK). Methods: Retrospective report of clinical data and histopathological analysis of excised corneal tissue. Results: A 63-year-old woman underwent uncomplicated DSAEK in her left eye due to endothelial dystrophy. During the first months after surgery, her visual acuity was 0.3, and a semilunar contraction gradually appeared at the edge of the graft. Over the following months, the fibrotic changes progressed and visual acuity decreased, with no improvement after uncomplicated cataract surgery. A successful penetrating keratoplasty was performed, and the excised corneal button with an attached posterior lamellar graft was histologically examined. The affected part of the graft consisted of a thickened fibrocellular tissue positive for glycosaminoglycans and smooth muscle actin. Conclusions: The present case demonstrates asymmetric fibrotic contraction of a DSAEK graft.

Both environmental and host factors influence risk of cutaneous melanoma (CM), and worldwide, the incidence varies depending on constitutional determinants of skin type and pigmentation, latitude, and patterns of sun exposure. We performed genetic analysis of CDKN2A, CDK4, BAP1, MC1R, and MITFp.E318K in Danish high-risk melanoma cases and found CDKN2A germline mutations in 11.3% of CM families with three or more affected individuals, including four previously undescribed mutations. Rare mutations were also seen in CDK4 and BAP1, while MC1R variants were common, occurring at more than twice the frequency compared to Danish controls. The MITF p.E318K variant similarly occurred at an approximately three-fold higher frequency in melanoma cases than controls. To conclude, we propose that mutation screening of CDKN2A and CDK4 in Denmark should predominantly be performed in families with at least 3 cases of CM. In addition, we recommend that testing of BAP1 should not be conducted routinely in CM families but should be reserved for families with CM and uveal melanoma, or mesothelioma.

Purpose. The pathogenesis of rhegmatogenous retinal detachment (RRD) remains incompletely understood, with no clinically effective treatment for potentially severe complications such as photoreceptor cell death and proliferative vitreoretinopathy. Here we investigate the protein profile of the vitreous following experimental retinal detachment using a comparative proteomic based approach. Materials and Methods. Retinal detachment was created in the right eyes of six New Zealand red pigmented rabbits. Sham surgery was undertaken in five other rabbits that were used as controls. After seven days the eyes were enucleated and the vitreous was removed. The vitreous samples were evaluated with two-dimensional polyacrylamide gel electrophoresis and the differentially expressed proteins were identified with tandem mass spectrometry. Results. Ten protein spots were found to be at least twofold differentially expressed when comparing the vitreous samples of the sham and retinal detachment surgery groups. Protein spots that were upregulated in the vitreous following retinal detachment were identified as albumin fragments, and those downregulated were found to be peroxiredoxin 2, collagen-Iα1 fragment, and α-1-antiproteinase F. Conclusions. Proteomic investigation of the rabbit vitreous has identified a set of proteins that help further our understanding of the pathogenesis of rhegmatogenous retinal detachment and its complications.

BackgroundLens crystallines are special proteins in the eye lens. Because the epithelial basement membrane (lens capsule) completely encloses the lens, desquamation of aging cells is impossible, and due to the complete absence of blood vessels or transport of metabolites in this area, there is no subsequent remodelling of these fibers, nor removal of degraded lens fibers. Human tissue ultimately derives its (14)C content from the atmospheric carbon dioxide. The (14)C content of the lens proteins thus reflects the atmospheric content of (14)C when the lens crystallines were formed. Precise radiocarbon dating is made possible by comparing the (14)C content of the lens crystallines to the so-called bomb pulse, i.e. a plot of the atmospheric (14)C content since the Second World War, when there was a significant increase due to nuclear-bomb testing. Since the change in concentration is significant even on a yearly basis this allows very accurate dating.Methodology/principal findingsOur results allow us to conclude that the crystalline formation in the lens nucleus almost entirely takes place around the time of birth, with a very small, and decreasing, continuous formation throughout life. The close relationship may be further expressed as a mathematical model, which takes into account the timing of the crystalline formation.Conclusions/significanceSuch a life-long permanence of human tissue has hitherto only been described for dental enamel. In confront to dental enamel it must be held in mind that the eye lens is a soft structure, subjected to almost continuous deformation, due to lens accommodation, yet its most important constituent, the lens crystalline, is never subject to turnover or remodelling once formed. The determination of the (14)C content of various tissues may be used to assess turnover rates and degree of substitution (for example for brain cell DNA). Potential targets may be nervous tissues in terms of senile or pre-senile degradation, as well as other highly specialised structures of the eyes. The precision with which the year of birth may be calculated points to forensic uses of this technique.