LONDON MEDICAL AND PHYSICAL JOURNAL. EDITED BY JOHN NORTH, ESQ. F.L.S. MEMBER OF THE ROYAL COLLEGE OF SURGEONS, AND OF THE MEDICAL AND CHIRURGICAL SOCIETY OF LONDON. (VOL. LXV.) NEW SERIES, VOL. IX. Et quoniam variant morbi, variabimus artes; LONDON: JOHN SOUTER, 73, ST. PAUL'S CHURCH-YARD; AND TO BE HAD OF ALL THE MEDICAL BOOKSELLERS. 1831. E Medical and Physical Journal. NO 377, VOL. LXIV.] JULY 1830. [No 49, New Series. For many fortunate discoveries in medicine, and for the detection of numerous errors, the world is indebted to the rapid circulation of Monthly Journals; and there never existed any work to which the Faculty, in Europe and America, were under deeper obligations than to the Medical and Physical Journal of London, now forming a long but an invaluable series.-Rush. ORIGINAL PAPERS, AND CASES, CHRONIC OPHTHALMIA. On the Proximate Causes of Chronic Ophthalmia. THERE is a species of indolent inflammation of the cornea, which we frequently meet with in practice, of a very stubborn and intractable nature, occasioning severe suffering to the patient, and frequently much embarrassment to the practitioner. I desire to offer a few remarks upon this disease: I am induced to do so from having lately met with several cases of this description, which yielded within a moderate time to the exhibition of appropriate remedies. Inflammations of the eye, of an acute nature, generally arise from those causes which induce similar affections in other organs; but there are specific agents to which, from its exposed situation, the eye is more peculiarly obnoxious: to enumerate these would occasion unnecessary prolixity in the present communication, which I intend to render as brief and concise as the nature of the subject will admit. The form of inflammation which I am now considering may be materially modified in its manifestations by the idiosyncrasy of the individual. I lately had a person under my care who had chronic inflammation of the cornea, of several years' duration, and whose prevailing diathesis appeared to be the rheumatic: the affection was considerably alleviated by the administration of colchicum, combined with calomel and opium; the local disease subsiding under the alteration of the constitutional action. In the sup No. 377.-No. 49, New Series. B pression of local affections, too much attention can scarcely be paid to the state of the constitution. I am persuaded, however, that, in many diseases of particular organs, and more especially of the eye, the irritative sympathy of contiguity will be found to influence materially the progress of the morbid phenomena; and, although a remote or sympathetic irritant may have called the primary disease into action, yet the consecutive changes in the phenomena thus produced will vary with the intensity of action and proximity of the local irritation. In the course of this paper, I shall have occasion to advert to some particular examples of this nature, and shall for the present proceed to consider the succession of morbid phenomena which is exhibited during the progress of this disease. The primary symptoms are either of an acute or subacute nature: in the scrofulous diathesis, the latter generally prevails. If the acute form exist, the symptoms are, of course, of a more aggravated nature; the congestion of the sanguiferous vessels more conspicuous, and the epiphora and intolerance of light more troublesome. After these symptoms have existed for an indefinite period, the state of chronic inflammation becomes permanently established, and the nature of the exciting cause will be found to have changed, as the phenomena exhibited in the chronic cases are varying from those of the acute. The primary proximate causes of the acute inflammation may be either idiopathic or sympathetic irritation. This irritation first excites the diseased action, and subsequently accelerates it, accompanying the inflammatory action to the complete destruction of the diseased organ. When the inflammation is of the passive kind, the capillary congestion in many cases proves an exciting cause to the morbid action of the congested vessels. The physical distention is a stimulus to the arterial tubes, and one of the sources of the prolonged irritability of the eye. It is curious to trace the chain of these phenomena, of the varying operations of the causes and effects, and of the several morbid changes resulting from their combined actions. Let us consider the dilatation of the arterial calibers of the more superficial vessels, the sympathetic irritation which it necessarily excites, and the preternatural actions dependent upon that irritation. The transparent vessels, when distended with red blood, become considerably congested; they occupy certain spaces which were appropriated to the reception of other vessels, and the reticulated cellular tissue is lacerated in consequence of their displacement. Upon the first admission of arterial blood in larger quantities into these vessels, the irritability of their parietes is necessarily augmented. The physical distention of the containing organs is the next phenomenon resulting from the increased momentum of the scarlet stream. When the arterial tubes are first excited to action, the power of resistance may be nearly equivalent to the momentum of impression. The successive waves of blood, acted upon by the vis à tergo and by the specific action excited in the radical branches by the stimulus of congestion, augment the impelling powers. This may be called the active inflammatory stage. At this period, the pain is acute and pungent; the secretions are hot and acrid; the tears more especially offending the irritable organ, and excoriating the adjacent parts. These symptoms continue for an indefinite time; their nature changes as the phenomena vary from the acute stage: the irritability of the organ begins to subside. The cause of this effect is worthy of consideration. We have before observed that, at the first invasion of the disease, the additional quantity of blood proves a stimulus to the substance of the arterial tubes. This stimulus is that specific principle of irritability resident in the blood: whether this be a chemical or a galvanic agent, it is not necessary in this place to inquire. It may be expedient, however, to observe that this principle of irritability is attracted by the parietes of the living arteries, and communicates, by its specific stimulus, the susceptibility which they possess. The ingress of the blood is rapid, but its egress from the tube by no means equivalent to the primary invasion. A physical distention of the organ necessarily ensues; the blood, being detained in its transit, imparts to the beating artery a much greater portion of its specific stimulus than is consistent with its own vitality. This lifeimparting fluid dies, in the very act of furnishing to the excited organ the final minimum of its principle of irritability. Having expended this, it becomes chemically decomposed, and the fibrine, adhering to the internal parietes, intercepts for a time the acquisition of the vital stimulus by the walls of the artery, from the current of blood which now passes with little impediment through the tube. The resistance of irritability being thus overcome in the vessel, the power of elasticity subsides also, and the only obstruction offered to the laceration of the tube exists in the mechanical power of resistance, resident in the substantial density of the arterial walls. The contracting |