DOI: 10.5301/ejo.5000400

Eur J Ophthalmol 2014; 24 ( 3 ): 437-440

CASE REPORT

Central retinal vein occlusion in a young patient following cannabis smoke inhalation Federico Corvi1, Giuseppe Querques1,2, Rosangela Lattanzio1, Chiara Preziosa1, Maurizio Battaglia Parodi1, Francesco Bandello1 1 2

Department of Ophthalmology, San Raffaele Scientific Institute, Vita-Salute University, Milan - Italy Department of Ophthalmology, University Paris Est Creteil, Centre Hospitalier Intercommunal de Créteil, Créteil - France

Purpose: To report a case of central retinal vein occlusion (CRVO) following cannabis smoke inhalation in a young patient. Methods: An otherwise healthy 18-year-old man without risk factors for retinal vein occlusion presented with reduced visual acuity (20/200) secondary to CRVO following cannabis smoke inhalation. Central retinal vein occlusion was diagnosed on the basis of slit-lamp fundus biomicroscopy and fluorescein angiography. Results: Tests for systemic causes were negative. Following one intravitreal dexamethasone implant (Ozurdex) and one ranibizumab injection (Lucentis), functional (20/20 visual acuity) and anatomic improvement was recorded. Fluorescein angiography showed a decrease in the vascular caliber and tortuosity, with no signs of retinal ischemia or edema. Conclusions: We report CRVO in a young adult following cannabis smoke inhalation. Its occurrence immediately after cannabis smoking further supports a link between the use of cannabis and vascular alterations. Keywords: Cannabis, Central retinal vein occlusion, Delta-9-tetrahydrocannabinol, Ozurdex, Ranibizumab Accepted: November 8, 2013

INTRODUCTION The main users of cannabis are adolescents and young adults (1). Cannabis, a drug extracted form the female inflorescence of Cannabis sativa, contains different psychoactive constituents. The primary and most important is delta-9-tetrahydrocannabinol (THC) (2). Cannabis smoking is increasing in frequency and the reasons are related to its effects: relaxation, self-confidence, and general sense of well-being. Cannabis is also known to have adverse effects, however, in particular panic reaction, anxiety, and the risk of vehicle crashes (1). Other important adverse effects are the risk of dependence, psychotic symptoms/schizophrenia, and cardiovascular disease such as angina, myocardial infarction, and stroke (2).

No ocular vascular complications have been reported in the literature. Retinal vein occlusion (RVO) is one of the most important blinding vascular retinal disorders, and usually in the elderly it is related to hypertension. On the other hand, vasculitis and coagulopathies are the most frequent causes in young adults (3). We describe a case of a central RVO (CRVO) in a young adult following cannabis smoke inhalation.

MATERIALS AND METHODS An 18-year-old man presented 8 days after a sudden decrease in vision in his left eye (LE).

© 2013 Wichtig Editore - ISSN 1120-6721

437

CRVO following cannabis smoke inhalation

Fig. 1 - Color fundus photography, fluorescein angiography (FA), and spectraldomain optical coherence tomography (SD-OCT) at the diagnosis of central retina vein occlusion (CRVO). Fundus photography (A) shows retinal veins congestion and tortuosity, deep dot-blot and superficial flame-shaped hemorrhages, cotton-wool spots, and macular edema. The FA late phase frames (B) reveal diffuse blood–retinal barrier breakdown and perfusion defects, with perivascular leakage and ischemic confluent areas, especially in the temporal sectors. Horizontal SD-OCT scan (C) shows cystoid macular edema and subretinal fluid accumulation, responsible for meaningful retinal thickening (central macular thickness was 1134 μm).

Best-corrected visual acuity (BCVA) was 20/20 in the right eye (RE) and 20/200 in the LE with metamorphopsia. The patient was in good general health and reported onset of ocular symptoms immediately after smoking cannabis (approximately 15 minutes). He had smoked occasionally, only a part of a joint, for 8 months, with daily abuse in the last 2 weeks. This was the first time he had smoked an entire joint. On slit-lamp examination, no abnormalities were found in the anterior chamber of both eyes; intraocular pressure was 12 mm Hg in both eyes. Fundus examination of the RE was unremarkable, while the LE showed tortuosity and engorgement of all branches of the central retinal vein, dot/ blot and flame-shaped hemorrhages, cotton-wool spots, and optic disc and macular edema (Fig. 1A). Fluorescein angiography (FA) was performed and revealed in the LE a delayed arteriovenous transit time, central masking by retinal hemorrhages, perivascular leakage, areas of capillary nonperfusion, and vessel wall staining (Fig. 1B). Horizontal spectral-domain optical coherence tomography (SD-OCT) showed the presence of cystoid macular edema (CME) and subretinal fluid accumulation, responsible for meaningful retinal thickening (Fig. 1C).

RESULTS On the basis of these findings, the patient was diagnosed with CRVO in LE, and underwent a comprehensive systemic 438

work-up. Full blood count, renal profile, liver function test, and thyroid function test were normal. Thrombophilic screening tests (prothrombin time, partial thromboplastin time, thrombin time, lupus anticoagulant and anticardiolipin antibody, anti-β-glycoprotein-I antibody, activated protein C resistance, factor V Leiden mutation, prothrombin mutation, protein S deficiency, protein C deficiency, fibrinogen tests, and homocysteine levels) were all normal. Holter and electrocardiogram monitoring were also normal. After giving written informed consent, the patient underwent sustained-release dexamethasone injection (0.7 mg intravitreal implant; Ozurdex, Center Valley, Pennsylvania, USA). Two weeks later, BCVA in the LE slightly improved (20/100) and intraocular pressure was still 12 mm Hg in both eyes. Fundus examination of the LE showed persistence of tortuosity and engorgement of all branches of the central retinal vein and dot/blot and flame-shaped hemorrhages (Fig. 2A), while SD-OCT showed a reduction of CME (Fig. 2B). In order to consolidate and improve the anatomic and functional results, we decided to also perform an intravitreal injection of ranibizumab (0.5 mg/0.05 mL; Lucentis, Genentech, Newtown, Pennsylvania, USA). One month later, BCVA improved to 20/20, and intraocular pressure was still 12 mm Hg in both eyes. Fundus examination showed almost normalization of the vessels course and caliber (only slight increased vascular tortuosity), and regression of the hemorrhages (Fig. 3A). The FA showed a decrease in the vascular caliber and tortuosity, with no

© 2013 Wichtig Editore - ISSN 1120-6721

Corvi et al

Fig. 2 - Color fundus photography and spectral-domain optical coherence tomography (SD-OCT) 2 weeks after intravitreal dexamethasone implant. Fundus color photography (A) shows reduction of retinal veins congestion and intraretinal hemorrhages. Intravitreal dexamethasone implant is clearly visible in the inferior sector. Horizontal SD-OCT scan (B) reveals reduction of retinal thickness (central macular thickness was 405 μm).

Fig. 3 - Color fundus photography, fluorescein angiography (FA), and spectraldomain optical coherence tomography (SD-OCT) 1 month after intravitreal ranibizumab injection. Fundus color photography (A) shows almost normalization of the vessels course and caliber (only slight increased vascular tortuosity) and regression of the hemorrhages. The FA frames (B) reveal almost normal central and peripheral vascular perfusion. Horizontal SD-OCT scan (C) shows regression of macular edema, with normalization of retinal profile and foveal depression (central macular thickness was 253 μm).

© 2013 Wichtig Editore - ISSN 1120-6721

439

CRVO following cannabis smoke inhalation

signs of retinal ischemia or edema (Fig. 3B). The SD-OCT showed disappearance of CME and the presence of normal foveal depression (Fig. 3C). During follow-up, the patient did not inhale cannabis smoke.

DISCUSSION In this report, we describe CRVO in a young adult following cannabis smoke inhalation, which was effectively treated by intravitreal implant and Lucentis. The mechanism of cannabis-induced CRVO is not known. Our patient presented symptoms immediately after (approximately 15 minutes) the end of smoking cannabis, and it is noteworthy that THC is rapidly distributed to the tissues, reaching a maximum level in the bloodstream even before the end of smoking (4). Given that the effects are generally seen within 15 minutes after a peak and lasting for up to 3 hours, and are believed to be mediated through sympathetic stimulation and reduced parasympathetic activity (5), it is not surprising that in our patient CRVO did not develop coincidentally with cannabis smoke inhalation. The effects of smoking cannabis are different and linked to the distribution of their specific receptors, cannabis receptor 1 and 2 (CB1 and CB2), which are found in the brain, heart, blood vessels, spleen, and cells of the immune system (6). Delta-9-tetrahydrocannabinol can result in a rapid and substantial dose-dependent increase in the heart rate by as much as 20%-100%, reduce left ventricular ejection time, facilitate atrioventricular node conduction, and effect a modest increase in blood pressure and eventual increase in cardiac output by as much as 30% or more (5). Orthostatic hypotension and both syncope and near-syncope can occur as a result of decreased peripheral vascular resistance

in the skeletal muscle (5). the Hemodynamic fluctuation secondary to cannabis smoking likely can promote CRVO. Deusch et al (7) demonstrated in vitro that THC has an effect on cell membrane of human platelets, where they found CB1 and CB2. In particular, in a concentration-dependent manner, THC is able to increase the expression of glycoprotein IIb-IIIa and P-selectin. These functional results may suggest a receptor-dependent pathway of THC-induced platelet activation. Therefore, the platelets’ activation could make a platelet clot that facilitates the formation of CRVO. Despite changes systemically induced by THC, in our patient CRVO developed unilaterally. However, in young patients with different systemic conditions, such as hyperhomocysteinemia, hypercoagulable state, or autoimmune vascular diseases, CRVO presentation is also typically unilateral. We hypothesize that since THC effects on the vessels are receptor-mediated, a different distribution or availability of these receptors, possibly influenced by previous exposure, may be responsible for a difference in the vascular autoregulation from side to side. In conclusion, we report CRVO in a young adult following cannabis smoke inhalation. Its occurrence immediately after cannabis smoking supports a link between the use of cannabis and systemic vascular alteration. Financial Support: No financial support was received for this submission. Conflict of Interest Statement: None of the authors has conflict of interest with this submission. Address for correspondence: Giuseppe Querques Department of Ophthalmology University Vita Salute San Raffaele Via Olgettina 60 20132 Milan Italy [email protected]

REFERENCES

4.

1.

5.

2. 3.

440

Hall WD, Pacula RL. Cannabis Use and Dependence: Public Health and Public Policy. Cambridge, UK: Cambridge University Press; 2003. Hall WD, Solowij N. Adverse effects of cannabis. Lancet 1998;352:1611-6. Rogers S, McIntosh RL, Cheung N, et al. International Eye Disease Consortium: The prevalence of retinal vein occlusion: pooled data from population studies from the United States, Europe, Asia, and Australia. Ophthalmology 2010;117:313-9.

6.

7.

Bachs L, Morland H. Acute cardiovascular fatalities following cannabis use. Forensic Sci Int 2001;124:200-3. Sidney S. Cardiovascular consequences of marijuana use. J Clin Pharmacol 2002;42(11 Suppl):64S-70S. Institute of Medicine. Marijuana and Medicine: Assessing the Science Base. Washington, DC: National Academy Press; 1999. Deusch E, Kress HG, Kraft B, Kozek-Langenecker SA. The procoagulatory effects of delta-9-tetrahydrocannabinol in human platelets. Anesth Analg 2004;99:1127-30.

© 2013 Wichtig Editore - ISSN 1120-6721

Central retinal vein occlusion in a young patient following cannabis smoke inhalation.

To report a case of central retinal vein occlusion (CRVO) following cannabis smoke inhalation in a young patient...
313KB Sizes 0 Downloads 0 Views