|Year : 2017 | Volume
| Issue : 3 | Page : 223-225
Remya Mareen Paulose
Little Flower Hospital and Research Center, Angamaly, Kerala, India
|Date of Web Publication||30-Jan-2018|
Dr. Remya Mareen Paulose
Little Flower Hospital and Research Center, Angamaly, Kerala
Source of Support: None, Conflict of Interest: None
Torpedo maculopathy is a rare congenital maculopathy clinically seen as a “torpedo”-shaped lesion temporal to the fovea. We hereby report a 4-year-old female child who on routine evaluation for refractive correction was discovered to have a temporal macular RPE defect with a pointed-oval shape directed toward the foveola. The ophthalmic examination revealed best-corrected visual acuity of 6/12 in both eyes without any changes in biomicroscopy. Her ocular and systemic medical history was unremarkable. Torpedo maculopathy diagnosis was based on the characteristic shape and peculiar location.
Keywords: Hypopigmented nevus, optical coherence tomography, retinal pigment epithelium, torpedo maculopathy
|How to cite this article:|
Paulose RM. Torpedo maculopathy. Kerala J Ophthalmol 2017;29:223-5
| Introduction|| |
Torpedo maculopathy is an asymptomatic, torpedo-shaped defect in the retinal pigment epithelium (RPE) which occurs in the temporal macular region with a pointed tip directed towards the foveola. Originally, Roseman and Gass (1992) described this lesion as “a hypopigmented nevus of the retinal pigment epithelium.” It is a rare benign disorder characterized by hypopigmented congenital nevus of RPE located along the horizontal raphe without significant vision loss. Its synonyms are solitary hypopigmented nevus, amelanotic nevus, hypomelanotic or albinotic nevi of RPE, solitary amelanotic spot, congenital hypomelanotic freckle, paramacular albinotic spot syndrome, and paramacular coloboma.,,,,,,, Being a hypopigmented lesion of the RPE, it resembles some pigment-related disorders such as choroidal melanoma, nevus, congenital hypertrophy of RPE, and congenital-pigmented lesions having the potential of malignancy as in Gardner's syndrome. Here, we report a case with torpedo maculopathy because it is a rare disorder which needs to be promptly differentiated from the above conditions.
| Case Report|| |
A 4-year-old female child with bilateral compound myopic astigmatism was referred to a retina clinic for the evaluation of a hypopigmented lesion in her right fundus. Under cycloplegia, her best-corrected visual acuity was 6/12 in both eyes (refractive correction right eye – 10.5 DS/−2.50 DC at 180°, left eye – 11 DS/−2.00 DC at 180°). She had no remarkable medical history of any systemic and ocular disease. Pupils were round, equal, and reactive to light with no afferent pupillary defect. Biomicroscopy of the anterior segment was unremarkable. Noncontact tonometry measured an intraocular pressure of 14 and 16 mmHg in the right and left eye, respectively. On binocular indirect ophthalmoscopy, a flat, hypopigmented, fusiform chorioretinal lesion with well-defined margins and a tip pointing toward the fovea located at the temporal portion in the right eye was seen [Figure 1]a. The lesion had a fraying tail toward the temporal aspect. The peripheral retina was normal and devoid of any chorioretinal lesions bilaterally. The retinal examination of the left eye was unremarkable [Figure 1]b. Optical coherence tomography (OCT) revealed inner segment-outer segment irregularity with RPE thinning and hyperreflectivity of the underlying choroid in the area of torpedo maculopathy [Figure 1]c. Based on the characteristic clinical picture and location of the lesion, a diagnosis of torpedo maculopathy was made. The child was advised refractive correction. Because of the nonprogressive nature of the condition, we recommended yearly follow-up for the child in the retina clinic.
|Figure 1: (a) Right eye fundus showing a flat, hypopigmented, fusiform chorioretinal lesion with well-defined margins and a tip pointing toward the fovea located at the temporal portion. (b) Normal fundus in the left eye. (c) Inner segment-outer segment irregularity with retinal pigment epithelium thinning and hyperreflectivity of the underlying choroid in the area of torpedo maculopathy|
Click here to view
| Discussion|| |
Torpedo maculopathy is a congenital lesion of the RPE characterized by its very unique shape and location. It is usually detected as an accidental finding. Roseman and Gass initially described the lesion in a 12-year-old male with normal visual acuity. They observed a solitary oval lesion, located temporal to the macula with a wedge-shaped tail that obscured the choroidal layers. They hypothesized that the hypopigmentation was due to the abnormal melanin deposition in intact RPE cells. Subsequently, Daily  referred this lesion as “paramacular albinotic spot syndrome.” Later, Teitelbaum et al. coined the term “torpedo maculopathy” based on its pathognomonic shape. Typically, the nasal margin of the lesion is a sharply pointed “head” which is directed toward the fovea. Two different configurations of the temporal margin have been described rounded or frayed tail. Review of the literature finds that reports of torpedo maculopathy lesions do, in fact, vary significantly in many of their clinical characteristics. The clinical features of torpedo maculopathy have been summarized in [Table 1].
Because the central fovea is not involved in most torpedo lesions, visual acuity is generally not affected., In rare instances, vision can be reduced, particularly if the lesion is impinging on the fovea, but this is more likely when ocular comorbidities are present. Visual function may also be compromised by visual field loss, usually in the form of a central scotoma observed on standard automated perimetric testing.,
The etiology of torpedo maculopathy remains speculative, and some have credited abnormal choroidal development or ciliary vasculature development leading to the localized, nonprogressive RPE lesion. Pian suggested it may a developmental defect in the nerve fiber layer at the horizontal raphe. The uniform location and size of this condition points toward a congenital defect during fetal development of the RPE as reported by Shields et al.
The diagnosis of this disorder is made clinically. However, multimodal imaging including fundus fluorescein angiography (FFA), OCT, and fundus autofluorescence might also be useful for diagnosis and differential diagnosis. FFA can reveal a transmission hyperfluorescence or RPE window defect in lesion region.,, OCT will show retinal thinning, increased choroidal reflectance or RPE hyporeflectivity, and shallow serous neurosensory detachment and subretinal cleft.,,, In a recent study on OCT findings in torpedo maculopathy, two patterns of abnormality as type 1 and 2 were identified by Wong et al. Type 1 has normal inner retina, attenuation of interdigitation zone and ellipsoid zone in the outer retina, without outer retinal cavitation. Type 2 has normal inner retina, thinning of outer nuclear layer, loss of interdigitation zone and ellipsoid zone in the outer retina and outer retinal cavitation with or without inner choroidal excavation. Recently, the OCT angiography (OCTA) findings associated with torpedo lesions were described by Papastefanou et al., with OCTA choroidal vascular segmentation showing hyporeflectivity (atrophy) correlating to the OCT subretinal cleft.
The differential diagnosis must include choroidal lesions (melanoma and nevus), congenital anomalies of the RPE, and focal retinal pigmentation due external agents (traumatic or drug-induced toxic effects).,,, They are summarized in [Table 2].
Although a stable lesion, torpedo maculopathy needs routine monitoring as the possibility of complications exists. In rare cases, the lesions can progress leading to degeneration of the retina, RPE, and choroid. In addition, subsequent neurosensory retinal detachment has also been observed. Annual monitoring is recommended, with testing ranging among fundus examination, OCT, and macular threshold perimetry. These patients can self-monitor for any visual change with a home Amsler grid.
| Conclusion|| |
In our case, examination and ancillary test findings were consistent with a diagnosis of torpedo maculopathy. Although diagnosis can be made based on appearance and location of the lesion, new technology aids in confirming the diagnosis.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Roseman RL, Gass JD. Solitary hypopigmented nevus of the retinal pigment epithelium in the macula. Arch Ophthalmol 1992;110:1358-9.
Golchet PR, Jampol LM, Mathura JR Jr., Daily MJ. Torpedo maculopathy. Br J Ophthalmol 2010;94:302-6.
Daily MJ. Torpedo maculopathy or paramacular spot syndrome. In: New Dimensions in Retina: November 10-13, Chicago; 1993.
Barbazetto IA, Maris PJ Jr., Greenstein VC. Solitary albinotic spot of the retinal pigment epithelium: A functional and imaging study. Klin Monbl Augenheilkd 2008;225:295-7.
Pian D, Ferrucci S, Anderson SF, Wu C. Paramacular coloboma. Optom Vis Sci 2003;80:556-63.
Shields CL, Guzman JM, Shapiro MJ, Fogel LE, Shields JA. Torpedo maculopathy at the site of the fetal “bulge”. Arch Ophthalmol 2010;128:499-501.
Rigotti M, Babighian S, Carcereri De Prati E, Marchini G. Three cases of a rare congenital abnormality of the retinal pigment epithelium: Torpedo maculopathy. Ophthalmologica 2002;216:226-7.
Pilotto E, Zannin ME, Convento E, Cortese M, Midena E. Torpedo maculopathy: A morphofunctional evaluation. Int Ophthalmol 2013;33:71-4.
Mercan K, Turgut B, Üneşi E, Çatak O. Torpedo maculopathy: A case report. New Front Ophthalmol 2015;1. [Doi: 10.15761/NFO.1000109].
Teitelbaum BA, Hachey DL, Messner LV. Torpedo maculopathy. J Am Optom Assoc 1997;68:373-6.
Shields JA, Shields CL, editors. Tumours and related lesions of the pigment epithelium. In: Intraocular Tumours: An Atlas and Textbook. 2nd
ed. Philadelphia, PA: Lippincott Williams and Wilkins; 2008. p. 431-80.
Tsang T, Messner LV, Pilon A, Lombardi L. Torpedo maculopathy: In-vivo
histology using optical coherence tomography. Optom Vis Sci 2009;86:E1380-5.
Trevino R, Kiani S, Raveendranathan P. The expanding clinical spectrum of torpedo maculopathy. Optom Vis Sci 2014;91:S71-8.
Wong EN, Fraser-Bell S, Hunyor AP, Chen FK. Novel Optical Coherence Tomography Classification of Torpedo Maculopathy. Clin Exp Ophthalmol 2014;43:342-8.
Papastefanou VP, Vázquez-Alfageme C, Keane PA, Sagoo MS. Multimodality imaging of torpedo maculopathy with swept-source, en face optical coherence tomography and optical coherence tomography angiography. Retin Cases Brief Rep 2016. [Epub ahead of print].
[Table 1], [Table 2]