The 2014 Bowman Lecture&Mdash
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Eye (2015) 29, 46–64 & 2015 Macmillan Publishers Limited All rights reserved 0950-222X/15 www.nature.com/eye RCOPHTH EPONYMOUS LECTURE The 2014 Bowman J Marshall Lecture—Bowman’s and Bruch’s: a tale of two membranes during the laser revolution Abstract surgeon at the Royal London Ophthalmic Hospital (Moorfields Eye Hospital) becoming a To describe the historical evolution of the surgeon at the institution in 1851. His role of lasers in effecting therapeutic contributions to medicine were rewarded with a changes in the four acellular membranes of Baronetcy in 1884. It should be remembered, the eye. Over the past 50 years, iterative however, that he was an extremely modest and developments have been instituted in lasers humble man who throughout his life never used used for various forms of eye surgery the eponymous labels associated with his many predominately on the basis of data generated discoveries preferring Malpighi capsule for in early experiments in the 1960s to glomerular capsule (Bowman’s capsule); radial determine thresholds for damage and their fibres of the ciliary muscle (Bowman’s muscle); incorporation in codes of practice for laser the glands in the olfactory mucosa (Bowman’s safety. The evolutionary steps are described. glands); and anterior elastic membrane for Excimer laser technology resulted in the Bowman’s membrane. In 1883, the Council of generation of the new field of laser refractive the Ophthalmic Society of the United Kingdom surgery with over 40 million individuals honoured its founder Sir William Bowman by now having undergone procedures such as inaugurating the Bowman lectures in photorefractive keratectomy and LASIK. recognition of his distinguished scientific Developments in lasers used for various position in Ophthalmology and other branches forms of retinal surgery have undergone of medicine and in commemoration of his changes involving shorter and shorter pulse valuable services to the Ophthalmological durations together with changes in beam Society, of which he was the first President. The energy distribution with implications Bowman lecturers were charged with delivering for potential intervention in AMD a lecture, which should consist of a critical prophylactically. Lasers have made a major review of recent advances in a given field of Institute of Ophthalmology, impact on surgical treatment on all four Ophthalmology. My predecessors have University College London, acellular membranes of the eye but expounded in detail on the many and varied London, UK particularly Bowman’s membrane in refractive contributions made to our understanding of surgery, where it has been demonstrated that Correspondence: tissues by William Bowman and also his role in it can be removed without significant J Marshall, Institute of developing Ophthalmology in the United consequences for eye health or vision. Ophthalmology, University Kingdom.1,2 I was therefore particularly College London, 11-43 Eye (2015) 29, 46–64; doi:10.1038/eye.2014.240 Bath Street, London honoured and somewhat intimidated on being EC1V 9EL, UK. asked to deliver the 65th lecture in this series as Tel: þ 44 (0)7802157156; I am not an ophthalmologist. Like almost all of Fax: þ 44 (0)2076086991. In February 1840, William Bowman qualified as the previous lecturers, I decided to look E-mail: eye.marshall@ a doctor, and 1 year later, at the remarkably backwards before going forwards. Bowman googlemail.com young age of 25 years, he was elected a Fellow interacted with the elite of Victorian society; he Received: 20 August 2014 of the Royal Society for his seminal work on was a contemporary of Dickens, corresponded Accepted in revised form: striated muscle; however, he had to wait a with Darwin over organisational matters 27 August 2014 further 6 years (1846) to be appointed assistant concerning the 1851 great exhibition, and with The 2014 Bowman Lecture J Marshall 47 Florence Nightingale over the passage of nurses to could be considered as the tendons of the eye as they Scutari in the Crimea. It should be remembered, provide incredibly strong structures deformable only however, that the vast majority of people within the within certain elastic limits and effectively run around United Kingdom lived a very different life in a very the circumference of the globe. Together these two different environment. The plight of the poor is amply systems provide a biomechanical infrastructure to allow described by Dickens in his many novels,3 and the for the containment of intraocular pressure, pressure seminal works of Mayhew such as ‘London Labour and fluctuations due to cardiac cycle, the dissipation of forces London Poor’.4 These moving descriptions are supported implicit in accommodation, and tensional changes by the graphical if depressing and threatening induced by the contraction and relaxation of extraocular illustrations of Gustaf Dore in his work ‘London: A muscles. pilgrimage’.5 I claim a tenuous link with history in that In a review of the literature, it seems that Bowman Bowman helped Florence Nightingale at a time when her remains unchallenged in describing his membrane in a endeavours to alleviate the suffering of British soldiers paper published in 1847.9 By contrast, Descemet’s were not looked upon with favour by the British membrane has several claimants for discovery and was Government.6 At the age of 4 years, Sir Harold Ridley sat first described in a paper by an Englishman, Benedict upon the lap of Florence Nightingale and presumably Duddell in 172910 some 30 years before the publication of she was kind to him. Sir Harold was certainly kind to me Jean Descemet in 1759.11 Although Duddell seems to when I was feeling particularly bruised by peers who have been ignored by Descemet, there was a great deal of thought that changing the properties of the optical zone controversy as to whose name should be apportioned of the cornea was as dangerous, and possibly even more to the membrane from another Frenchman, Pierre unpopular, than his own concept of introducing a plastic Demours, who published in 1767.12 Perhaps, we should lens into the eye subsequent to cataract surgery. At a bar take a typically unBritish stance and rename this in Torquay he asked me why I was looking so depressed membrane Duddell’s membrane. The lens capsule and when I told him it was because of peer criticism, remains unburdened by an eponymous label and he said ‘I have been through that my boy and the only various individuals seem to have discovered or alluded way to deal with such ill informed critics is to live to it over many years. The first is in a manuscript by 13 longer than them’. I am forever grateful to him for his Rufus of Ephesus in 100AD, followed by Christoforus advice and for providing this somewhat tenuous link to Scheiner in the 1500s,14 Anthony van Leeuwenhoek in Bowman. As the 65th Bowman lecturer, I would the 1600s, and Johann Gottfried Zinn15 in the 1700s. first like to draw attention to all my predecessors Bruch was also lucky in having no real contenders (Figure 1). This is an incredible group of people, for previously describing his membrane as although including 2 peers of the realm, 8 knights, and 28 the Polish anatomist Frederick Ruysch described professors, a truly humbling alumni and certainly one asystemcalledtunicaReischiana,16 this was a representing the greats of ophthalmology. In the face of composite structure almost certainly involving this array, I felt a little like Sydney Carton on proceeding pigment epithelium, what we now call Bruch’s to the guillotine in ‘A Tale of Two Cities’ and to amend membrane17 and a significant portion of the choroidal his famous statement, ‘It is a far, far better thing that I vasculature. HOPEIdo,thanIhaveeverdone’.7 Hence, the title of All of these membranes have in common the presence my lecture. of collagen, which provides their rigidity. In Bowman’s My chosen subject brings together my interest in two membrane, the collagen fibrils are extremely small in remote structures in the eye together with a technology, diameter (24–27 nm) and highly interwoven before which has had a major impact throughout the globe, interacting with the basement membrane of the corneal lasers. It would also appear to be the first Bowman’s epithelium anteriorly and the larger diameter collagen lecture to spend a significant amount of time describing fibres (32–36 nm) within the lamellae of the stroma research on Bowman’s membrane, although I have to anteriorly.18 By contrast, there are two layers of collagen confess my contribution has been essentially to destroy it. within Bruch’s membrane, which are separated by a In the past, the acellular membranes of the eye, the so- layer of elastin (Figure 3).19 The inner collagenous layer is called ‘glass membranes’,8 have received scant attention adjacent to the basement membrane of the retinal from clinicians but have promulgated lengthy and pigment epithelium, whereas the outer collagenous layer heated discussion by anatomists and histopathologists. is associated with the basement membrane of the Moving from the front of the eye to the back, these four endothelial cells of the choriocapillaris and runs into the membrane systems are Bowman’s membrane, intercapillary columns. With age most acellular Descemet’s membrane, the capsule of the lens, and membranes increase in thickness and this is certainly the Bruch’s membrane (Figure 2). Bowman’s and Bruch’s case for all such membranes within the eye,18,19 with the Eye The 2014 Bowman Lecture J Marshall 48 Figure 1 Illustrations of all 64 Bowman lecturers