Open Veterinary Journal, (2023), Vol. 13(5): 620–628 ISSN: 2226-4485 (Print) Original Research ISSN: 2218-6050 (Online) DOI: 10.5455/OVJ.2023.v13.i5.15 Submitted: 13/10/2021 Accepted: 17/04/2023, Published: 16/05/2023 Prevalence of ocular findings and their association with glycemia in dogs with diabetes mellitus: A 10-year clinical study (2009–2019) Francisco Cantero1,2, Ángel Ortillés1,2, M. Teresa Peña1,2 and Marta Leiva1,2* 1 Servei d’Oftalmologia, Fundació Hospital Clínic Veterinari, Universitat Autònoma de Barcelona, Bellaterra, Spain 2 Departament de Medicina i Cirurgia Animals, Facultat de Veterinària, Universitat Autònoma de Barcelona, Bellaterra, Spain Abstract Background: Although ocular findings in diabetic patients are well described, prevalence data for those is unknown. Aim: To describe the prevalence of ocular findings and their association with glycemia in dogs with diabetes mellitus. Methods: Medical records from diabetic dogs assessed by the ophthalmology and the internal medicine services at the Veterinary Teaching Hospital of the Autonomous University of Barcelona were reviewed (2009–2019). Results: Seventy-five dogs (150 eyes) of both genders (51/75 females; 68% and 24/75 males; 32%) and a mean age of 9.37 ± 2.43 years, were included. The most common ocular findings were cataracts (146/150; 97.3%), vitreous degeneration (45/98; 45.9%), anterior uveitis (47/150; 31.3%), aqueous deficiency dry eye (ADDE) (33/150; 22%), diffuse corneal edema (31/150; 20.7%), non-proliferative retinopathy (13/98; 13.3%), and lipid keratopathy (9/150; 6%). The most prevalent type of cataracts observed (78/146; 53.4%) was intumescent, which was commonly accompanied by non-proliferative retinopathy (p = 0.003). Among the diabetic dogs, blood glucose levels were statistically higher in dogs with non-proliferative retinopathy or anterior uveitis (p < 0.005). Conclusions: Ocular complications of diabetes mellitus in dogs are numerous, being the most frequent intumescent cataracts, vitreous degeneration, anterior uveitis, ADDE, diffuse corneal edema, and non-proliferative retinopathy. This high prevalence warrants a more detailed ophthalmic evaluation in diabetic dogs especially for those undergoing cataract surgery. Furthermore, a predisposition for anterior segment inflammation and non-proliferative retinopathy is suggested when fasting plasma glucose is higher than 600 mg/dl.. Keywords: Cataracts, Glucose, Intumescent, Phacoemulsification, Retinopathy. Introduction Ocular findings being historically associated with Diabetes mellitus (DM) is a common endocrine disorder DM in dogs are as follows: keratoconjunctivitis sicca characterized by chronic hyperglycemia resulting (Cullen et al., 2005; Williams et al., 2007; Gemensky- from a deficit in insulin production, action, or both Metzler et al., 2015), polymegathism and pleomorphism (Fracassi, 2017). The prevalence of DM in dogs has in corneal endothelial cells (Yee et al., 1985), corneal been estimated from 0.3% in first-opinion practices to hypoesthesia (MacRae et al., 1982), non-healing corneal 1% in referral institutions (Guptill et al., 2003; Fracassi ulcers (Good et al., 2003), lipid keratopathy (Crispin, et al., 2004; Davison et al., 2005; Mattin et al., 2014). 2002), corneal xanthogranulomas (Harvey et al., Two clinical forms are recognized in dogs: insulin- 2020), corneal abscesses (Michau, 2020), intracorneal dependent and non-insulin-dependent. The former is stromal hemorrhages (Matas et al., 2012; Violette and the most common, being characterized by permanent Ledbetter, 2017), lipid-laden aqueous humor (Violette hypoinsulinemia and, thereby, necessitating regular and Ledbetter, 2019; Schechtmann et al., 2020), exogenous insulin to maintain glycemic regulation cataracts (Miller and Brines, 2018), lens-induced (Fracassi, 2017). Unfortunately, glycemic control can uveitis (Paulsen et al., 1985), phacomorphic glaucoma be difficult to attain in some insulin-dependent dogs, (Williams, 2004), vitreous degeneration (West et al., resulting in chronic exposure to high blood levels of 2020), non-proliferative retinopathy (Landry et al., glucose and ketoacidosis that can lead to systemic 2004), and peripheral neuropathies (Katherman and complications. Eyes are particularly vulnerable to Braund, 1983). Unfortunately, until now, there are no the pathophysiological changes that occur because studies reporting the prevalence of ocular findings in of chronic hyperglycemia, and consequently, ocular diabetic canine patients nor the association between complications are a common finding in DM.  those and glucose blood levels. Thus, the present study *Corresponding Author: Marta Leiva. Servei d’Oftalmologia, Fundació Hospital Clínic Veterinari, Universitat Autònoma de Barcelona, Bellaterra, Spain. Email: marta.leiva@uab.cat Articles published in Open Veterinary Journal are licensed under a Creative Commons Attribution-NonCommercial 4.0 International License 620 http://www.openveterinaryjournal.com F. Cantero et al. Open Veterinary Journal, (2023), Vol. 13(5): 620–628 was conducted to describe the prevalence of the most of pigment on the anterior capsule were present; and common ocular findings in diabetic dogs, as well as to intumescent, when the size of the lens was bigger than establish if there is a correlation between ophthalmic normal, lens sutures were broken, and/or liquid was findings and blood glucose levels. seen within the lens. Similarly, the degree of anterior uveitis was also graded semiquantitatively (on a scale Materials and Methods from trace to +4) based on conjunctival congestion, Inclusion criteria aqueous flare (0 to +4), ocular hypotony, and miosis Medical records of dogs evaluated by the or resistance to mydriasis after tropicamide application. ophthalmology service at the Veterinary Teaching Non-exudative uveitis was considered when previous Hospital of the Autonomous University of Barcelona signs were present, but no visible aqueous flare was between 2009 and 2019 were retrospectively reviewed. observed. Phacomorphic glaucoma was diagnosed Dogs were included in the study if diagnosed with when intraocular pressure (IOP) increased over 25 DM by a board-certified specialist in small animal mmHg, the anterior chamber depth was diminished and internal medicine or a resident-in-training under direct no alterations were observed on gonioscopy. Vitreous supervision. DM was diagnosed by means of three degeneration was diagnosed by B-mode ultrasound findings as follows: appropriate clinical signs (polyuria, examination and graded using a previously reported polydipsia, polyphagia, and weight loss), persistent scheme whereby the vitreous degeneration is classified fasting hyperglycemia (>200 mg/dl), and glycosuria. into four grades (0–III), depending on the number of Animals with systemic hypertension were excluded echoes seen on ultrasonography (Labruyère et al., from the study because of the important co-morbidity 2008). Non-proliferative diabetic retinopathy was that those patients could have with the ocular findings. considered if retinal petechia or subretinal hemorrhages Blood pressure measurement was performed during were present and no systemic hypertension was internal medicine evaluation or during preanesthetic detected. examination, and in all cases animals were excluded Statistical analysis if systolic readings were over 160 mmHg. In all dogs, Quantitative results were reported by the mean and ophthalmic examination included neuro-ophthalmic standard deviation (SD) or median and range for evaluation, Schirmer tear test I (STT-1) (MSD Animal normally or non-normally distributed data, respectively Health, Madison, NJ), slit-lamp biomicroscopy (Kowa (as assessed by the Kolmogorov-Smirnov test). SL-15 and -17®; Kowa Company Ltd., Tokyo, Japan), Qualitative results were described by absolute and rebound tonometry (TonoVet® using “d” setting; Icare relative frequencies. Fisher's exact test was used for Finland Oy, Helsinki, Finland), and fluorescein stain qualitative variables, and unpaired t-test and Mann– (FluoroTouch®; Madhu Instruments, New Delhi, Whitney U test for quantitative variables. For all India). In addition, binocular indirect ophthalmoscopy statistical analyses, a commercial software (SPSS (Heine Omega 500®, Heine, Herrsching, Germany), 25.0®; IBM, Chicago, IL) was used, and a significance gonioscopy, and B-mode ultrasonography were threshold of p < 0.05 was set. performed when applicable. Animals were excluded if Ethical approval primary glaucoma, evidence of trauma, or infectious This paper refers to a retrospective study with no diseases were detected. animals involved in the experimental process, so no Data retrieval consent of ethics is needed for this study. Data collected and reviewed from the medical records included signalment (breed, age, and gender), Results levels of fasting glycemia at the time of the ocular Medical records of 75 diabetic dogs met the inclusion examination, eye/s affected, ophthalmic findings, criteria (150 eyes). The mean (±SD) age of the study whether or not cataract surgery was performed and population at first ophthalmic examination was 9.37 post-phacoemulsification ocular fundus findings. years (±2.43 years). There were 12 castrated males Ophthalmic findings: diagnosis and grading system (16%), 12 intact males (16%), 27 spayed females Aqueous deficiency dry eye (ADDE) was considered (36%), and 24 intact females (32%). Twenty-nine dog when STT-1 readings were under 15 mm/minute and breeds were identified in the study population, including no signs of corneal or conjunctival inflammation mix breed (27/75 dogs; 36%), Yorkshire Terrier (4/75; were observed. Cataract classification was established 9.3%), West Highland White Terrier (4/75; 5.3%), according to what was previously reported (Leiva and English Cocker Spaniel (4/75; 5.3%), Golden Retriever Peña, 2020): incipient, when lens opacity extended from (3/75; 4%), and one or two dogs from 24 other different 1% to 15%; immature when opacity covered between breeds. 16%–99% and fundic reflection was still able to be Ophthalmic findings visualized; mature, when the whole lens was affected Ocular lesions and their prevalence are summarized and no fundic reflection was visible after maximal in Figures 1 and 2, and shown in Figure 3. All dogs mydriasis; hypermature, when cortex resorption, had bilateral, although not always symmetrical, capsule wrinkling, capsule plaques, or deposition clinical findings. Cataract was the most common 621 http://www.openveterinaryjournal.com F. Cantero et al. Open Veterinary Journal, (2023), Vol. 13(5): 620–628 Fig. 1. Graph depicting the prevalence of ocular findings associated with DM in dogs with ocular signs. Fig. 2. Sectorial graph showing results regarding type of cataract and its prevalence in diabetic dogs. ocular finding (146/150 eyes; 97.3%), being bilateral eyes (2/146; 1.4%) (Fig. 2). Vitreous degeneration was in all the affected dogs. Intumescent cataracts were the second most common ocular finding (45/98 eyes; seen in 78 eyes (78/146; 53.4%), mature cataracts in 45.9%), being bilateral in 21 dogs (21/24; 87.5%), and 24 eyes (24/146; 16.4%), hypermature and immature unilateral in 3 (3/24; 12.5%). According to Labruyere´s in 21 eyes each (21/146; 14.4%), and incipient in 2 scoring system, grade I vitreous degeneration was 622 http://www.openveterinaryjournal.com F. Cantero et al. Open Veterinary Journal, (2023), Vol. 13(5): 620–628 retinopathy was detected in 13/98 eyes (13.3%) examined within 7 days after phacoemulsification, being bilateral in 5 patients (5/8; 62.5%) and unilateral in 3 patients (3/8; 37.5%). Ocular fundus examination revealed intraretinal punctate hemorrhages in 13 eyes and preretinal hemorrhages in 6 eyes. The statistical analysis evaluating the correlation between the type of cataracts and the other ocular findings is displayed in Table 1. Interestingly, non- proliferative retinopathy was the only ocular finding directly associated wsith cataracts (p = 0.003), specifically with intumescent cataracts (5/12; 42%). Table 2 shows the statistical association between fasting glycemia and each ocular finding, depicting a significant correlation between blood glucose levels, non-proliferative retinopathy (p = 0.000), and anterior uveitis (p = 0.013). These findings suggest a predisposition for anterior segment inflammation and non-proliferative retinopathy when fasting plasma glucose is higher than 600 mg/dl. Fig. 3. Images of the main ocular lesions seen in diabetic Discussion dogs. (a): intumescent cataract; (b): phacolytic uveitis; (c): The present work provides new information on the non-proliferative retinopathy; (d): vitreous degeneration ophthalmic findings associated with DM in dogs that grade II with hypermature cataract. could be helpful in the prevention and management of recorded in 35/45 eyes (77.7%) and grade II in 10 eyes diabetic ocular disease. Also, shows a direct association (22.3%) (Labruyère et al., 2008). Anterior uveitis was between blood glucose levels and some of the most the next most common finding (47/150 eyes; 31.3%), commonly identified ocular findings concomitant being bilateral in 18 dogs (18/29; 62%) and unilateral with the disease. This suggests that 600 mg/dl may be in 11 dogs (11/29; 38%). In 6 of those eyes, uveitis established as a cut-off value from which some ocular was classified as non-exudative (6/47; 12.8%) and in clinical signs, such as non-proliferative retinopathy and 41 eyes as exudative (41/47; 87.2%). Of the latter, 31 anterior uveitis, may be more frequently seen. eyes were classified as mild (31/41; 75.6%), 7 eyes as Different epidemiologic studies suggest that some moderate (7/41; 17.1%), and 3 eyes as severe (3/41; canine breeds are at higher risk of developing DM 7.3%). ADDE was diagnosed in 33/150 eyes (22%), (Guptill et al., 2003; Fracassi et al., 2004; Cullen et al., being bilateral in 10 dogs (10/13; 77%), and unilateral 2005). To the authors´ knowledge, there are no reports in 3 (3/13; 23%). The mean STT-1 value for the on whether there is a breed predisposition to develop affected and unaffected animals was 10.9 ± 3.00 and 20 secondary ocular signs. In the present study, mix breed ± 3.4 mm/min, respectively. Despite these values, only dogs were clearly overrepresented, but this fact could 4 eyes showed overt corneal secondary changes (4/33; indicate regional differences in breed distribution, rather 12.1%). Diffuse corneal edema was encountered in than a true predisposition for ocular complications of 31/150 eyes (20.7%), with 12 dogs affected bilaterally DM. According to previous reports (Guptill et al., 2003; (12/19; 63.1%) and 7 dogs unilaterally (7/19; 36.9%). Fall et al., 2007), middle-aged to older females were Lipid keratopathy was detected in 9/150 eyes (6%) the most commonly affected by DM, with a similar with 4 animals being affected bilaterally (4/5; 80%). incidence of ocular findings. Although neutering Unilateral phacomorphic glaucoma was found in status has been associated with better glycemic control 2/150 eyes (1.3%). Gonioscopy was performed as part (Guptill et al., 2003), the findings herein suggest that of the preoperative protocol in those cases in which neutering status may not influence the prevalence of phacoemulsification was elected. We used the actual ocular complications associated with DM. European College of Veterinary Ophthalmologists Cataract was the most prevalent finding in this (ECVO) approved gonioscopy scheme and all animals population of diabetic dogs with ophthalmic clinical were classified as non-affected, but a narrow angle was signs (97.3%), intumescent cataract being the most detected in 10 eyes [(5 dogs); 10.2%], partially narrow common. This agrees with previous studies in which in 18 eyes [(9 dogs); 18.4%], and fibra latae < 50% of cataracts were consistently found as the main ophthalmic circumference in 13 eyes [(7 dogs); 13.2%]. complaint in diabetic animals (Ling et al., 1977). In Phacoemulsification was performed in 98 eyes (98/150 fact, Beam et al. (1999) stated that 75% of the canine eyes; 65.3%), allowing for postoperative ocular fundus population diagnosed with DM will develop cataracts examination in all of them. Non-proliferative diabetic by approximately 12 months after the first diagnosis of 623 http://www.openveterinaryjournal.com F. Cantero et al. Open Veterinary Journal, (2023), Vol. 13(5): 620–628 Table 1. Statistical correlation between ophthalmic findings (in absolute frequencies) and type of cataracts in diabetic dogs. Statistically significant p-values are underlined and in italics. A significance threshold of p < 0.05. Cataracts (n = 146) Ocular signs Incipient Immature Mature Hypermature Intumescent p-value (n = 2) (n = 21) (n = 24) (n = 21) (n = 78) ADDE (n = 31) 1 3 5 4 18 0.508 Lipid keratopathy (n = 9) 0 2 2 0 5 0.708 Diffuse corneal edema (n = 31) 0 2 5 4 20 0.358 Anterior uveítis (n = 40) 0 3 4 7 26 0.355 Vitreous degeneration (n = 44) 1 3 12 4 24 0.137 Non-proliferative retinopathy (n = 12) 1 2 2 2 5 0.003 Phacomorphic glaucoma (n = 2) 0 0 0 0 2 1.000 Table 2. Glycemia levels are shown as mean ± SD in diabetic dogs with ocular findings. For each ocular finding, the statistical results of the evaluation between affected and non-affected eyes are shown, establishing a significance threshold of p < 0.05. Significant p-values are underlined and in italics. Glycemia (mg/dl) Ocular signs Mean ± SD p-value ADDE (n = 31) 430.20 ± 84.20 0.623 Diffuse corneal edema (n = 31) 477.11 ± 119.91 0.617 Lipid keratopathy (n = 9) 522.25 ± 147.10 0.147 Anterior uveitis (n = 47) 494.78 ± 110.48 0.013 Phacomorphic glaucoma (n = 2) 507.56 ± 122.71 0.936 Incipient (n = 2) 538.50 ± 168.99 0.590 Immature (n = 21) 467.54 ± 98.98 0.844 Cataract Mature (n = 24) 505.93 ± 153.33 0.483 (n = 146) Hypermature (n = 21) 418.50 ± 136.69 0.526 Intumescent (n = 78) 454.38 ± 92.75 0.827 Vitreous degeneration (n = 44) 486.63 ± 137.44 0.501 Non-proliferative retinopathy (n = 12) 645.88 ± 41.94 0.000 diabetes. It is well-known that intumescent cataracts have high sensitivity and specificity when diagnosing develop due to an osmotic imbalance secondary to vitreous diseases (Labruyère et al., 2008). Vitreous intralenticular sorbitol accumulation. The speed of degeneration was surprisingly the second most development depends on sugar concentration and common ocular finding (45.9%) in the present study. endogenous activity of aldose reductase, which very Most of the affected eyes displayed a mild degree often ends with an acute onset cataract (Engerman et of the condition (77.7%), not showing a statistical al., 1982). This acute onset is often the main complaint correlation with the type of cataracts (p > 0.05). This for requesting an ophthalmologic examination, which agrees with Park et al. (2015) who found an increased could explain why intumescent was the most common degree of vitreous degeneration when associated with type of cataracts seen in the present study. chronic cataracts (mature or hypermature), but not with Vitreous degeneration is an age-related ocular acute, intumescent, incipient, or immature cataracts. condition in dogs, with a higher prevalence in female Similarly, Krishnan et al. (2020) ruled out a possible dogs (Krishnan et al., 2020). In fact, it is described correlation between vitreous degeneration and other that dogs have 24 times more likelihood of developing ocular comorbidities, such as cataracts, lens luxation, vitreous degeneration per year of age (Krishnan et al., glaucoma, and/or retinal detachment. 2020). In the present study, due to the impossibility Tear film dysfunction, both aqueous and evaporative, has of fully evaluating and grading the condition by been documented in dogs (Cullen et al., 2005; Williams biomicroscopy, a B-mode ultrasound was performed et al., 2007) and humans (Manaviat et al., 2008) with for this purpose. This technique has been reported to DM. Human medicine studies have demonstrated 624 http://www.openveterinaryjournal.com F. Cantero et al. Open Veterinary Journal, (2023), Vol. 13(5): 620–628 that while basal rates of aqueous tear secretion were diabetic for an average of 123 days and had cataracts equivocal between diabetic and nondiabetic patients, for an average of 39 days. In the present study, no STT values were lower in diabetics (Goebbels, 2000). cases of phacoclastic uveitis were diagnosed. Based on In the present study, ADDE was found in 22% of the the low amount of aqueous flare, the majority of the dogs. Surprisingly, many of these animals had no uveitis cases were classified as mild anterior phacolytic obvious clinical signs at diagnosis, making it possible exudative uveitis (75.6%). to go undetected if no STT-1 had been performed. Diabetic corneal endothelial changes have been widely Duration of diabetic disease has been considered a risk described in the human literature, but in veterinary factor for ADDE, as it negatively influences STT-1 medicine, they are scarcely reported (Yee et al., values in diabetic dogs (Williams et al., 2007). Diabetic 1985). Conversely to what has been described in dogs undergoing phacoemulsification have been human medicine (Shenoy et al., 2008; El-Agamy and reported to be almost twice as likely to develop dry eye Alsubaie, 2017; Liaboe et al., 2017), diabetic dogs within the first 2-week postoperative period, compared exhibit pleomorphism and polymegathism but no to nondiabetic dogs. Tear supplementation rather changes in endothelial density (Yee et al., 1985). These than an institution of a stimulant tear product may be changes appeared to be indirectly correlated with the considered to protect the cornea during the anesthetic level of diabetic control (Yee et al., 1985). This should and surgery recovery period as tear values may improve be taken into consideration when assessing patients after the 2-week postoperative period (Gemensky- for phacoemulsification surgery, as it may predispose Metzler et al., 2015). Furthermore, small diabetic dogs diabetic dogs to more severe postoperative corneal (<10 kg) have been reported as 1.7 times more likely edema. Furthermore, preoperative specular microscopy to be diagnosed with dry eye postoperatively rather could help in presurgical decision making, such as than small nondiabetic dogs (Gemensky-Metzler et viscoelastic selection, phacoemulsification machine al., 2015). It is unclear as to whether poor DM control settings, or postoperative use of topical hyperosmotic is an important factor in the manifestation of dry eye drugs. diseases in diabetic canines as has been documented in Punctate retinal hemorrhages were found in 13.3% humans (Ozdemir et al., 2003). Some canine studies of the eyes examined (out of 98 eyes assessed by suggest no significant correlation between poor DM indirect ophthalmoscopy). This prevalence markedly control and low STT (Cullen et al., 2005; Williams et differs from reports in human medicine, in which al., 2007); however, no complete cohort observational the prevalence is much higher (Herring et al., 2014). studies evaluating this factor have been published to Conversely to the proliferative changes seen commonly date. in humans (Manaviat et al., 2008), canine diabetic Anterior uveitis was the third most common clinical retinopathy is characterized by microvascular changes finding in the study (31.3%). It has been reported that including capillary microaneurysms and hemorrhages 71% of patients with cataracts will show lens-induced (Braga-Sá et al., 2018). The pathogenesis of diabetic uveitis (LIU) elicited by an inflammatory response retinopathy has been hypothesized to be the same as for that occurs secondary to protein leakage from the cataract formation (Muñana, 1995). In one retrospective lens capsule occurs (also known as phacolytic uveitis) study, retinal hemorrhages following cataract surgery (Paulsen et al., 1985). The degree of inflammation in dogs occurred in 21% of diabetic patients with only depends on the amount of soluble and insoluble proteins 0.6% of nondiabetics having these lesions (Landry et within the lens (Wilcock and Peiffer, 1987). Taking this al., 2004). While the median time from diagnosis of into consideration, it is expected that LIU secondary diabetes to the onset of non-proliferative retinopathy to DM would be more severe in young patients than in dogs has been reported as 1.4 years (Landry et al., in older ones, as albuminoid proteins inside the lens 2004), the proliferative retinopathy commonly seen increase with age (Ortwerth and Olesen, 1989). Young in humans has been associated with longer periods of animals have a higher number of soluble proteins time. The lower incidence of proliferative changes in that can diffuse through intact lens capsules when dogs might be explained by the age of onset of DM an intumescent cataract develops quickly in diabetic and the shorter life span of dogs, yielding a shorter patients. Although no correlation was found between duration of disease during their lifetime (Miller and the degree of uveitis and the type of cataract, it was Brines, 2018). Furthermore, differences in the presence more commonly diagnosed in dogs with intumescent of vascular endothelial growth factor in the aqueous cataracts. Another mechanism for LIU in diabetic humor of diabetic patients with retinopathy (Funatsu et dogs is associated with the rapid increase in the size of al., 2005) could explain these interspecies disparities. intumescent cataracts, thus leading to tears in the lens Dr. Williams found that diabetic cataracts had capsule at the equator (phacoclastic uveitis) (Wilkie significantly increased axial thickness compared et al., 2006). This type of uveitis tends to be more to non-diabetic cataracts as demonstrated by aggressive and to have a more acute onset. Wilkie et B-mode ultrasonography (Williams, 2004). This al. (2006) reported that dogs affected with spontaneous reinforces the recommendation for performing early lens capsule rupture had, based on their histories, been phacoemulsification to reduce the risk of phacomorphic 625 http://www.openveterinaryjournal.com F. Cantero et al. Open Veterinary Journal, (2023), Vol. 13(5): 620–628 glaucoma. In the present study, a very low incidence Leiva, and Teresa Peña designed the study and had of phacomorphic glaucoma was documented which can direct patient contact. Francisco Cantero obtained be explained by the short time between DM diagnosis all data supervised by Marta Leiva and Teresa Peña. and the ophthalmic examination. Angel Ortillés analyzed the data and gave statistical Phacoemulsification is the gold standard treatment for conclusions. Francisco Cantero, Angel Ortillés, and cataracts in dogs. Although the success rate in diabetic Marta Leiva wrote the paper. Teresa Peña, Marta Leiva, dogs is approximately the same as that for cataract and Angel Ortillés critically reviewed the manuscript extraction in nondiabetic patients (Bagley and Lavach, for important intellectual content. 1994), postoperative complications such as corneal ulcers, diffuse corneal edema, lipemic aqueous humor, References and ocular neuropathies have been reported to be more Bagley, L.H. and Lavach, J.D. 1994. Comparison of likely to develop in diabetic dogs (MacRae et al., 1982; postoperative phacoemulsification results in dogs Ledbetter et al., 2006; Klein et al., 2011; Foote et al., with and without diabetes mellitus: 153 cases 2019). Based on the prevalence of ocular signs observed (1991-1992). J Am Vet Med Assoc. 205(8), 1165– in the present study, and the incidence of postoperative 1169. complications reported, a more complete ocular Beam, S., Correa, M.T. and Davidson, M.G. 1999. 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