- Email: [email protected]
SOFT CONTACT LENSES
84
anical " effects of the reflux outweigh those of associated infection, early detection and correction of reflux may prove to be important in the prevention of scar formation. Continuous antibacterial drug administration is also said to prevent progressive scar formation .23 Until the relative importance of infection and factors such as vesicoureteric reflux and analgesic abuse have been properly assessed, the aim must be to eradicate infection and to prevent recurrent infection. Patients with recurrent infection should have further investigations including an intravenous pyelogram. Probably only a very small percentage of patients with recurrence develop progressive parenchymal scarring and renal failure. The observation that progressive parenchymal damage has been more frequently recorded in patients without overt infection 19-21,24 suggests that vesicoureteric reflux, analgesic abuse, and occult renal infection may play an important role in loss and scarring of the renal parenchyma in chronic progressive " pyelonephritis ".
MENSTRUAL REGULATION MENSTRUAL regulation is a term sanctioned more by usage than by semantic accuracy. It is the artificial removal of endometrium within two weeks after a missed menstrual period. It is usually performed where pregnancy is suspected but unproven either by pregnancy tests or by clinical examination. Several techniques are used, but a conference last month in Honolulu dwelt mainly on surgical aspiration of the uterus by means of a hand-held syringe and the Karman cannula. This is simple, cheap, and quick, and can be carried out without analgesia or with just a paracervical block. Participants from many countries agreed that paramedical workers could be taught to do it, provided there was supervision and surgical back-up for difficult cases.
The total experience with good follow-up is smallof a few thousand cases. Among the most extensive series are those of Stimm in New York (1900) and Hale and Pion in Hawaii. A trial in three London teaching hospitals has accumulated over 250 cases; and Mullick and his co-workers in Calcutta find the method acceptable to at least one group of Indian women. No serious side-effects have been noted, but minor uterine infection may be troublesome and some intrauterine pregnancies have continued after the procedure-a hazard that seems to diminish as the operator becomes more experienced. Are the short and long term illeffects of menstrual regulation less than those of firsttrimester abortion after 6-8 weeks of pregnancy ? The safety of first-trimester abortion by vacuum aspiration is well-established (in 261,700 of these procedures in New York in 1970-72 there were 3 deaths-a mortality-rate approaching 1 in 100,000). Before even the short-term consequences of menstrual regulation can be compared, a lot more experience will
a matter
23. 24.
Smellie, J. M., Normand, I. C. S. Urinary Tract Infection; p. 123. London, 1968. Angell, M. E., Relman, A. S., Robbins, S. L. New Engl. J. Med. 1968, 278, 1303.
be needed. A
difficult
in assessing the are not pregnant: who procedure how often is the operation redundant? Clearly such cases should be reduced as far as possible, and a number of ways have been suggested. Waiting for some days after the missed period can greatly increase the proportion of women who are pregnant at the time of menstrual regulation. And there are clinical clues too; special caution is needed when a woman has lately stopped taking oral contraceptives. Nearly all those at the Honolulu conference saw menstrual regulation as a supplement to contraceptive practice. It should be used to encourage contraception rather than as an excuse for women abandoning it. Experience suggests that a " pregnancy scare " can indeed be the basis of good contraceptive practice. Since pregnancy is terminated before the major developments of embryology are completed it also seems to be more acceptable emotionally, both to the woman and to the operator. Theologically it is acceptable to at least one group of Moslem thinkers, and some of the other major religions may well come to view it as preferable to abortion. In addition, many countries with restrictive abortion laws require proof of pregnancy before finding against an operator, so menstrual regulation may achieve special legal status. But perhaps the most important aspect of the procedure is that it allows a simple method of pregnancy termination to be linked with a method of pregnancy prevention. more
concerns
question
women
SOFT CONTACT LENSES OVER 90% of contact lenses in current use are hard " corneal " lenses 8-9 mm. in diameter, made of polymethyl methacrylate and readily fitted after measurement of the curvature of the patient’s cornea and his refractive error. About 80% of patients soon find that they can wear these lenses without discomfort for most of the day. Only very occasionally do the lenses produce a painful scratch of the cornea (which heals in a few days if the lens is left out), though the corneas of some regular lens-wearers show fine erosions which evidently cause no discomfort. Although a pair of hard corneal lenses costs only S8 wholesale, they are usually retailed at from E50 to S100; there are, however, excellent firms which still charge only S30. The hard " scleral " lens, which rests on the bulbar conjunctiva (and so does not press on the corneal epithelium), was the standard lens thirty years ago; but, being more difficult to fit and poorly tolerated, it is now used by less than 1% of contact-lens wearers, mainly those with specific corneal disorders (for " example, as a therapeutic " protective lens in keratoconus) when the simple corneal lens would not be satisfactory. Ten years ago the " soft " lens, made of a hydrophilic gel, was introduced, and has been given wide publicity. It is larger than the corneal lens (about 14 mm. diameter) and fragile, therefore less easy to handle, but most patients for whom the hard lens is too uncomfortable will readily tolerate the soft lens: it is sometimes known as the cocktail lens, since it can be slipped in and out whenever the social occasion
85
demands. These soft lenses are normally sold about double the price of the hard lenses. The soft lens is more immediately comfortable because the upper lid slides easily over it, and in the long term it is more readily tolerated since it permits freer permeation of oxygen to the underlying corneal epithelium: in tissue-culture1 the degree of cell damage was the same after two weeks beneath a corneal hard lens, after four weeks beneath a corneal hydrophilic lens, and after fifteen weeks beneath the standard soft scleral lens. Nevertheless, for most people the hard corneal lens should be the first choice. Not only is it cheaper, easier to handle, and easier to sterilise, but it also usually gives better vision (for the Much soft lens does not correct astigmatism). the attended arrival of soft these lenses, and, publicity as a result, many fitters purchased the necessary expensive equipment. Commercial pressures tend to result in over-ready prescription; and because these lenses are immediately comfortable they are apt to be provided by vendors who have scant knowledge of corneal physiology. Soft lenses should really be fitted only under medical supervision.
>
PROFUSE BLEEDING FROM THE COLON PROFUSE bleeding from the colon is an alarming and generally brings the patient quickly to the doctor. It may be defined as a " sudden episode of bright red or maroon bleeding per rectum, usually While associated with weakness or faintness" .1 much has been written about the management of bleeding from the upper gastrointestinal tract, relatively little attention has been given to similar episodes from the colon. This is because colonic
symptom
bleeding nearly always stops spontaneously and so the indication for operation and methods of emergency diagnosis are not well worked out. In many cases, the The commonest cause of bleeding is never found. cause of profuse bleeding is diverticular disease and it accounts for about half the cases, but the diagnosis is often reached by exclusion. Bleeding is more likely to happen when the diverticula are not complicated by inflammation 2,3and when the patient is hypertensive 3; but the exact site of the bleeding is uncertain. Ulcers have been demonstrated in the neck3 and at the base4 of a diverticulum. Other possible diagnoses include arteriovenous malformation (especially in younger patients), endometriosis, solitary rectal ulcer (which is usually traumatic), ischsemic bowel disease, secondary carcinoma, irradiation, and colonic varices. Hxmorrhoids and carcinoma occasionally give massive bleeding, while ulcerative colitis can usually be distinguished by the history and associated pus and mucus ; Meckel’s diverticulum must always be remembered. But, despite all these possible causes, a substantial proportion of cases remain undiagnosed. Anticoagulants and disorders of the clotting mechanism probably produce bleeding only in the presence of : another lesion, not from the intact normal mucosa. The history may give some clues to the site of the
Since blood from the stomach and duodenum may pass so rapidly through the intestine that it appears fresh at the rectum, it is of the greatest importance to exclude bleeding from the upper gastrointestinal tract. This can be done by passing a nasogastric tube to detect fresh blood or " coffee grounds " and by emergency gastroduodenoscopy. Emergency sigmoidoscopy is usually unhelpful since it merely confirms that the rectum is full of blood, but occasionally a rectal polyp or neoplasm is found. The mere presence of haemorrhoids must not lead to the assumption that they are the cause of the trouble, but sometimes they are seen to be bleeding. In most cases, once the bleeding has stopped a thorough investigation can be made of the properly prepared large bowel. Sigmoidoscopy and double-contrast barium enema are essential and colonoscopy may be
bleeding.
helpful. The greatest problems arise when the bleeding does not stop and an emergency operation is contemplated. Some surgeons have a policy that if 500 ml. of blood is required every 8 hours or if 1500 ml. or more is needed to stabilise the circulation, operation is urgently needed. Whereas in the upper gastrointestinal tract the bleeding ulcer is usually found fairly early, the decision to operate for colonic bleeding is only the beginning of the difficulties. The colon cannot be safely opened and the mucosa inspected as can the stomach. Selective clamping of different segments of the bowel to see which distends with blood is not very rewarding, nor is opening the transverse colon to see which half is bleeding.5 It is in localising the bleeding site that selective mesenteric angiography may have a valuable place .4,5,1,1 Some clinicians make this one of the first investigations, and a surprising number of lesions are being found in the right side of the colon by this means.S,7 The bleeding must be at the rate of about 0-5 ml. per minute6 (720 ml. per day) to be detected, and angiography is particularly useful in diagnosing arteriovenous malFor the upper gastrointestinal tract formations. rather poorly with fibre-optic compares angiography but for the colon it is probably the endoscopy, of choice when the bleeding does not investigation and is indicated. operation stop If the bleeding point cannot be localised and a Meckel’s diverticulum is excluded, a total colectomy will have to be done,lO with an immediate or delayed ileorectal anastomosis. If there is complete absence of diverticula in the right side of the colon, a left hemicolectomy will probably be sufficient. Whatever he decides to do, the surgeon must be sure the operation has been extensive enough to stop the bleeding. The patient is not in the best state to return to theatre 24 hours later, for removal of the other half of the colon because the bleeding persists. 5. 6. 7.
.
8. 1. 2. 3. 4.
Krejči, L., Krejčová, H. Br. J. Ophthal. 1973, 57, 675. Failes, D., Killingback, M. Aust. N.Z.J. Surg. 1973, 43, 28. Heald, R. J., Ray, J. E. Dis. Colon Rectum, 1971, 14, 420. Hill, G., Taubman, J. O. Am. J. dig. Dis. 1973, 18, 808.
9. 10.
Dunphy, J. E., Mikkelsen, W. P., Moody, F. G, Silen, W. Archs Surg. 1973, 107, 367. Nusbaum, M., Baum, S., Blakemore, W. S., Finkelstein, A. K. J. Am. med. Ass. 1965, 191, 389. Casarella, W. J., Kanter, I. E., Seaman, W. B. New Engl. J. Med. 1972, 286, 450. Cotton, P. B., Rosenberg, M. T., Waldram, R. P. L., Axon, A. T. R. Br. med. J. 1973, ii, 505. Kanter, I. E., Schwartz, A. J., Flemming, R. J. Am. J. Roentg. 1968, 103, 386. Judd, E. S. Surg. Clins N. Am. 1969, 49, 977.
anical " effects of the reflux outweigh those of associated infection, early detection and correction of reflux may prove to be important in the prevention of scar formation. Continuous antibacterial drug administration is also said to prevent progressive scar formation .23 Until the relative importance of infection and factors such as vesicoureteric reflux and analgesic abuse have been properly assessed, the aim must be to eradicate infection and to prevent recurrent infection. Patients with recurrent infection should have further investigations including an intravenous pyelogram. Probably only a very small percentage of patients with recurrence develop progressive parenchymal scarring and renal failure. The observation that progressive parenchymal damage has been more frequently recorded in patients without overt infection 19-21,24 suggests that vesicoureteric reflux, analgesic abuse, and occult renal infection may play an important role in loss and scarring of the renal parenchyma in chronic progressive " pyelonephritis ".
MENSTRUAL REGULATION MENSTRUAL regulation is a term sanctioned more by usage than by semantic accuracy. It is the artificial removal of endometrium within two weeks after a missed menstrual period. It is usually performed where pregnancy is suspected but unproven either by pregnancy tests or by clinical examination. Several techniques are used, but a conference last month in Honolulu dwelt mainly on surgical aspiration of the uterus by means of a hand-held syringe and the Karman cannula. This is simple, cheap, and quick, and can be carried out without analgesia or with just a paracervical block. Participants from many countries agreed that paramedical workers could be taught to do it, provided there was supervision and surgical back-up for difficult cases.
The total experience with good follow-up is smallof a few thousand cases. Among the most extensive series are those of Stimm in New York (1900) and Hale and Pion in Hawaii. A trial in three London teaching hospitals has accumulated over 250 cases; and Mullick and his co-workers in Calcutta find the method acceptable to at least one group of Indian women. No serious side-effects have been noted, but minor uterine infection may be troublesome and some intrauterine pregnancies have continued after the procedure-a hazard that seems to diminish as the operator becomes more experienced. Are the short and long term illeffects of menstrual regulation less than those of firsttrimester abortion after 6-8 weeks of pregnancy ? The safety of first-trimester abortion by vacuum aspiration is well-established (in 261,700 of these procedures in New York in 1970-72 there were 3 deaths-a mortality-rate approaching 1 in 100,000). Before even the short-term consequences of menstrual regulation can be compared, a lot more experience will
a matter
23. 24.
Smellie, J. M., Normand, I. C. S. Urinary Tract Infection; p. 123. London, 1968. Angell, M. E., Relman, A. S., Robbins, S. L. New Engl. J. Med. 1968, 278, 1303.
be needed. A
difficult
in assessing the are not pregnant: who procedure how often is the operation redundant? Clearly such cases should be reduced as far as possible, and a number of ways have been suggested. Waiting for some days after the missed period can greatly increase the proportion of women who are pregnant at the time of menstrual regulation. And there are clinical clues too; special caution is needed when a woman has lately stopped taking oral contraceptives. Nearly all those at the Honolulu conference saw menstrual regulation as a supplement to contraceptive practice. It should be used to encourage contraception rather than as an excuse for women abandoning it. Experience suggests that a " pregnancy scare " can indeed be the basis of good contraceptive practice. Since pregnancy is terminated before the major developments of embryology are completed it also seems to be more acceptable emotionally, both to the woman and to the operator. Theologically it is acceptable to at least one group of Moslem thinkers, and some of the other major religions may well come to view it as preferable to abortion. In addition, many countries with restrictive abortion laws require proof of pregnancy before finding against an operator, so menstrual regulation may achieve special legal status. But perhaps the most important aspect of the procedure is that it allows a simple method of pregnancy termination to be linked with a method of pregnancy prevention. more
concerns
question
women
SOFT CONTACT LENSES OVER 90% of contact lenses in current use are hard " corneal " lenses 8-9 mm. in diameter, made of polymethyl methacrylate and readily fitted after measurement of the curvature of the patient’s cornea and his refractive error. About 80% of patients soon find that they can wear these lenses without discomfort for most of the day. Only very occasionally do the lenses produce a painful scratch of the cornea (which heals in a few days if the lens is left out), though the corneas of some regular lens-wearers show fine erosions which evidently cause no discomfort. Although a pair of hard corneal lenses costs only S8 wholesale, they are usually retailed at from E50 to S100; there are, however, excellent firms which still charge only S30. The hard " scleral " lens, which rests on the bulbar conjunctiva (and so does not press on the corneal epithelium), was the standard lens thirty years ago; but, being more difficult to fit and poorly tolerated, it is now used by less than 1% of contact-lens wearers, mainly those with specific corneal disorders (for " example, as a therapeutic " protective lens in keratoconus) when the simple corneal lens would not be satisfactory. Ten years ago the " soft " lens, made of a hydrophilic gel, was introduced, and has been given wide publicity. It is larger than the corneal lens (about 14 mm. diameter) and fragile, therefore less easy to handle, but most patients for whom the hard lens is too uncomfortable will readily tolerate the soft lens: it is sometimes known as the cocktail lens, since it can be slipped in and out whenever the social occasion
85
demands. These soft lenses are normally sold about double the price of the hard lenses. The soft lens is more immediately comfortable because the upper lid slides easily over it, and in the long term it is more readily tolerated since it permits freer permeation of oxygen to the underlying corneal epithelium: in tissue-culture1 the degree of cell damage was the same after two weeks beneath a corneal hard lens, after four weeks beneath a corneal hydrophilic lens, and after fifteen weeks beneath the standard soft scleral lens. Nevertheless, for most people the hard corneal lens should be the first choice. Not only is it cheaper, easier to handle, and easier to sterilise, but it also usually gives better vision (for the Much soft lens does not correct astigmatism). the attended arrival of soft these lenses, and, publicity as a result, many fitters purchased the necessary expensive equipment. Commercial pressures tend to result in over-ready prescription; and because these lenses are immediately comfortable they are apt to be provided by vendors who have scant knowledge of corneal physiology. Soft lenses should really be fitted only under medical supervision.
>
PROFUSE BLEEDING FROM THE COLON PROFUSE bleeding from the colon is an alarming and generally brings the patient quickly to the doctor. It may be defined as a " sudden episode of bright red or maroon bleeding per rectum, usually While associated with weakness or faintness" .1 much has been written about the management of bleeding from the upper gastrointestinal tract, relatively little attention has been given to similar episodes from the colon. This is because colonic
symptom
bleeding nearly always stops spontaneously and so the indication for operation and methods of emergency diagnosis are not well worked out. In many cases, the The commonest cause of bleeding is never found. cause of profuse bleeding is diverticular disease and it accounts for about half the cases, but the diagnosis is often reached by exclusion. Bleeding is more likely to happen when the diverticula are not complicated by inflammation 2,3and when the patient is hypertensive 3; but the exact site of the bleeding is uncertain. Ulcers have been demonstrated in the neck3 and at the base4 of a diverticulum. Other possible diagnoses include arteriovenous malformation (especially in younger patients), endometriosis, solitary rectal ulcer (which is usually traumatic), ischsemic bowel disease, secondary carcinoma, irradiation, and colonic varices. Hxmorrhoids and carcinoma occasionally give massive bleeding, while ulcerative colitis can usually be distinguished by the history and associated pus and mucus ; Meckel’s diverticulum must always be remembered. But, despite all these possible causes, a substantial proportion of cases remain undiagnosed. Anticoagulants and disorders of the clotting mechanism probably produce bleeding only in the presence of : another lesion, not from the intact normal mucosa. The history may give some clues to the site of the
Since blood from the stomach and duodenum may pass so rapidly through the intestine that it appears fresh at the rectum, it is of the greatest importance to exclude bleeding from the upper gastrointestinal tract. This can be done by passing a nasogastric tube to detect fresh blood or " coffee grounds " and by emergency gastroduodenoscopy. Emergency sigmoidoscopy is usually unhelpful since it merely confirms that the rectum is full of blood, but occasionally a rectal polyp or neoplasm is found. The mere presence of haemorrhoids must not lead to the assumption that they are the cause of the trouble, but sometimes they are seen to be bleeding. In most cases, once the bleeding has stopped a thorough investigation can be made of the properly prepared large bowel. Sigmoidoscopy and double-contrast barium enema are essential and colonoscopy may be
bleeding.
helpful. The greatest problems arise when the bleeding does not stop and an emergency operation is contemplated. Some surgeons have a policy that if 500 ml. of blood is required every 8 hours or if 1500 ml. or more is needed to stabilise the circulation, operation is urgently needed. Whereas in the upper gastrointestinal tract the bleeding ulcer is usually found fairly early, the decision to operate for colonic bleeding is only the beginning of the difficulties. The colon cannot be safely opened and the mucosa inspected as can the stomach. Selective clamping of different segments of the bowel to see which distends with blood is not very rewarding, nor is opening the transverse colon to see which half is bleeding.5 It is in localising the bleeding site that selective mesenteric angiography may have a valuable place .4,5,1,1 Some clinicians make this one of the first investigations, and a surprising number of lesions are being found in the right side of the colon by this means.S,7 The bleeding must be at the rate of about 0-5 ml. per minute6 (720 ml. per day) to be detected, and angiography is particularly useful in diagnosing arteriovenous malFor the upper gastrointestinal tract formations. rather poorly with fibre-optic compares angiography but for the colon it is probably the endoscopy, of choice when the bleeding does not investigation and is indicated. operation stop If the bleeding point cannot be localised and a Meckel’s diverticulum is excluded, a total colectomy will have to be done,lO with an immediate or delayed ileorectal anastomosis. If there is complete absence of diverticula in the right side of the colon, a left hemicolectomy will probably be sufficient. Whatever he decides to do, the surgeon must be sure the operation has been extensive enough to stop the bleeding. The patient is not in the best state to return to theatre 24 hours later, for removal of the other half of the colon because the bleeding persists. 5. 6. 7.
.
8. 1. 2. 3. 4.
Krejči, L., Krejčová, H. Br. J. Ophthal. 1973, 57, 675. Failes, D., Killingback, M. Aust. N.Z.J. Surg. 1973, 43, 28. Heald, R. J., Ray, J. E. Dis. Colon Rectum, 1971, 14, 420. Hill, G., Taubman, J. O. Am. J. dig. Dis. 1973, 18, 808.
9. 10.
Dunphy, J. E., Mikkelsen, W. P., Moody, F. G, Silen, W. Archs Surg. 1973, 107, 367. Nusbaum, M., Baum, S., Blakemore, W. S., Finkelstein, A. K. J. Am. med. Ass. 1965, 191, 389. Casarella, W. J., Kanter, I. E., Seaman, W. B. New Engl. J. Med. 1972, 286, 450. Cotton, P. B., Rosenberg, M. T., Waldram, R. P. L., Axon, A. T. R. Br. med. J. 1973, ii, 505. Kanter, I. E., Schwartz, A. J., Flemming, R. J. Am. J. Roentg. 1968, 103, 386. Judd, E. S. Surg. Clins N. Am. 1969, 49, 977.