Annals of the Royal College of Surgeons of England (I979) vol 6i
British Association of Clinical Anatomists Abstracts of papers presented
the Annual General Meeting, 1979
The I979 Annual General Meeting of the British Association of Clinical Anatomists was held at Charing Cross Hospital Medical School, London, on 12th January. The following are abstracts of the papers read. Action of Vinca alkaloids on the mitotic prepared for electron microscopical examination using standard techniques. It appears that cortical spindle bone has similar capillaries to those found in skel-
J E Malcolm (Central Medical Establishment, Royal Air Force, London) The form of the mitotic spindle in prophase, e.g. in the red cell of larval Lepidosiren, exhibits prismatic crystal radiation as in scolecite and in geodes, while paracrystalline geometry applies to the form of retinal cells (Malcolm, J E, Blood Pressure Sounds and their Meanings. London, Heinemann, I963; Annals of the Royal College of Surgeons of England, 1973, 52, 279). Chromosomes in the anaphase are identified as giant peg-shaped paracrystal molecules in amphiphilic solution, arranged like confocal conic groups on a batonnet (see Hartshorne, H N, and Stuart, A, Crystals and the Polarising Microscope. London, Arnold, I970). The Vinca alkaloids determine a 'middle' (M1) phase, affecting the crystal habit of the spindle, just as traces of organic dyes affect that of potassium chlorate (see Buckley, H E, Crystal Growth. London, Wiley Chapman, 195I). This explains aggregation of mitotic tubulin paracrystals into parallel rods, hexagonal in cross-section, that are found in dividing cells of various species given Vinca alkaloids (Starling, D, Joiurnal of Cell Science, I976, 20, 78).
The structure of capillaries in cortical bone S Hughes and Margaret Blount (Orthopaedic Unit, Hammersmith Hospital and Royal Postgraduate Medical School, London) Transcapillary exchange in bone is by the process of passive free diffusion (Davies et al., Journal of Applied Physiology, I976, 40, I7). This movement appears to be unaffected by the size of the particles (Hughes et al., American Journal of Physiology, I977, 232, 3). However, the assumption is made that the capillaries in cortical bone are similar to the capillaries found in muscle-that is, they have transcapillary clefts through which these solutes can pass. These transcapillary clefts in skeletal muscle have been examined by Karnovsky (Journal of General Physiology, I1968, 52, 64S). The purpose of this investigation was to examine the structure of capillaries in cortical bone. Cortical bone from the ribs and fibulae of growing rats was embedded and
etal muscle in that there are transcapillary clefts and vesicles in the capillary wall through which solutes may pass. There does not appear to be any membrane surrounding these capillaries, which would bear out the findings in the physiological experiments that transcapillary exchange is a passive process unaffected by any membrane hindrance.
The ultrastructure of fibrils in human and animal tympanic membranes R, M H McMinn, D H Bosman, and S E Gschmeissner (Institute of Basic Medical Sciences, Royal College of Surgeons, London) Human tympanic membranes and those from a nuwnber of other species representing amphibians, birds, and mammals are currently being studied in order to investigate the nature of the fibrils of the connective tissue that intervenes between the external and internal epithelial layers. In the frog, chicken, and pigeon the fibrils are similar to those of many tendons, showing typical collagen banding and a range of diameters on transverse section. In some mammals such as the guineapig and mouse the fibrils have a square profile on transverse section and are apparently composed of four subunits as previously described by Lim (Acta otolaryngologica, I968, 66, i8i) and Johnson, McMinn, and Atfield (Journal of Anatomy, I968, I03, 297). In others like the rat and rabbit there are rounded fibrils among the square variety. In the human membrane collagenous and elastic fibres predominate, although Lim has reported the presence of the square variety as well (Acta otolaryngologica, I970, 70, 176). Examples of fibrils from various species were shown, together with illustrations of developing fibrils in human fetal tympanic membranes.
Reflexogenic systems in the larynx and their significance B Wyke (Neurological Unit, Royal College of Surgeons of England, London) Combined electromyographic and microphonic studies show that phonation involves a threefold sequence of precisely coordinated changes in motor
British Association of Clinical Anatomists unit activity in the intrinsic laryngeal muscles, as follows: (i) Prephonatory tuning, during which the vocal folds arc rapidly adducted (completely for voiced and incompletely for unvoiced sounds) across the advancing expiratory air stream some 50-I50 ms prior to each phonemic utterance. (2) Introphonatory modulation, which involves irregular, rapid adjustments of motor unit activity in the intrinsic muscles throughout each utterance, while the vocal folds remain adducted. (3i) Poistphonatory modulation, when further motor unit adjustments are superimposed in response to acoustic automonitoring of the vocal output. Neurohistological and neurophysiological studies have revealed that the events of Phase 2 are produced by the integrated activity of a triad of intrinsic laryngeal (tonic and phasic), reflexogenic systems (mucosal, myotatic, and articular). These are operated from low-thrcshold mechanoreceptors embedded respectively in the subglottic mucosa, in the intrinsic muscles themselves, and in the capsules of the intercartilaginous laryngeal joints. The structure and function of each of these three receptor systems were illustrated and their role in some clinical disorders of phonation (such as stammering) was considered.
Experimental hydrocephalus in rat and rabbit Patricia Collins and D Woollam (Department of
Anatomy, University of Cambridge) Hydrocephalus has been produced in animals of both species by (i) cistemal injection of either kaolin or siliconc, and (2) administration of vitamin Adeficient diet to the dam prior to pregnancy. Both the cause of hydrocephalus and the ependymal reaction to it have been studied by the scanning electron microscope. Particular attention has been paid to the morphology of those cells in the brain whose origin may broadly be termed 'ependymal'-choroid plexus epithelium, ependymal cells, and supraependymal macrophages. The significance of the findings was discussed.
The use of videotape for recording clinical neurological signs and theirprogress P A G Monro (Department of Anatomy, University
of Cambridge) Videotape has the great advantage over cine-recording that the demonstrator can not only observe the image as the recording is made but also replay the whole immediately and rerecord any part that may be imperfect. In addition, the patients can view the recordings and can then be reassured that they will not be shown in embarrassing positions which they might otherwise fear and resent. Examples shown included the progress of neurological injuries of the arm and an unusual crossed adductor reflex after patellar tap in a patient with a known lesion in the
The anatomy of the biliary tract in the living as demonstrated by peroperative and retrograde cholangiography G J Hadfield (Stoke Mandeville Hospital, Aylesbury) The anatomy of the living can be demonstrated by the various methods of cholangiography in use (Hadfield, G J, Annals of the Royal College of Surgeons of England, 1973, 52, 380). This paper described a personal experience of 8oo peroperative cholangiographies carried out as a routine during cholecystectomy and a smaller recent experience using retrograde methods. The normal anatomy and its variations in the liver and at the lower end of the duct were described. Examples of how these appearances can be changed or modified by physiological causes and pathological conditions were presented.
Some observations on the fetal development ofthe second part ofthe duodenum and the ampulia of Vater James Lister and I Baker Meio (Department of Paediatric Surgery, University of Liverpool) It has been proposed that congenital dilatation of the biliary system may be secondary to cholangitis resulting from pancreatic juice reflux, and an abnormal junction of the common bile duct and pancreatic duct has been shown to be a common patho,logical finding in congenital biliary atresia, choledochal cyst, and infantile hepatitis (Miyano, Suruga, and Suda, Journal of Pediatric Surgery, in press). Tandler in 1900 (Morphologisches Jahrbuch, 29, I87) proposed a theory of mucosal proliferation and recanalisation in the formation of the duodenum which on failure would result in atresia. Johnson (American Journal of Anatomy, I910, I0, 521) noted that the epithelial proliferation was most dense in the region of the developing common bile duct. Boyden, Cope, and Bill (American Journal of Surgery, I967, II4, 190) went further and demonstrated that the coalescence of vacuoles seemed to produce two parallel channels in the duodenum, and similar channels appeared in the developing biliary system. Reconstruction of the duodenum from a 21-mm embryo and serial sections of the second part of the duodenum in fetuses from 16-22 weeks showed some stages in the normal developmental anatomy in this region. The appearance of epithelial plugging with vacuoles in sections of the duodenum in the 2Imm embryo was shown on reconstruction to be produced by continuous serpiginous channels. The combined intramural channel of the bile and pancreatic ducts has a circular muscle around it and in addition the bile duct has a similar individual circular muscle just before the junction of the ducts and for a short distance after it, as described by Schwegler and Boyden (Anatomical Record, 19,37, 67, 44I). A combination of the oblique angle of junction of bile and pancreatic ducts within the duodenal wall and particularly the arrangement of circular muscle
British Association of Clinical Anatomists
around the common bile duct alone seems likely to be a major factor in the prevention of pancreaticobiliary reflux.
logical findings and their relevance to use of these materials as biliary tract prostheses were discussed.
Bile and healing of the traumatised bile Observations on the endocrine-like cells duct of the biliary tract H T Millington (Department of Surgery, Charing D J Riches and T L Georgy (Department of Anatomy, Charing Cross Hospital Medical School, London) Very little is known about the distribution and function of the endocrine-like cells of the biliary tract. This is partly due to the fact that they do not stain readily with the usual histochemical techniques. These cells have been studied, both histochemically and ultrastructurally, in biliary tracts from human fetuses and various animals. Generally, the endocrine-like cells are sparsely distributed, being located in the glands or diverticula of the bile ducts, particularly at their duodenal ends. Ultrastructurally, most cells contain electron-dense granules, 0.1-0.2 arm in diameter, situated between the nucleus and basal cell membrane. In guineapigs cholecystectomy did not appear to affect either the number or distribution of the endocrine-like cells in the common bile duct. With regard to development, endocrine-like cells could be distinguished in human fetal common bile ducts during the 4th and 5th months of intrauterine life. It is difficult to classify these cells structurally according to the scheme described elsewhere in the alimentary tract. However, their possible role in the control of biliary tract function was discussed.
Cross Hospital Medical School, London) In order to investigate the aetiology of benign postoperative bile duct strictures, the effects of clamping and/or pooling of bile around the bile duct have been studied in the rabbit. The bile duct was traumatised by clamping for 15 min with a microsurgical needle-hold-r. Poaled bile was achieved by injecting I.5 ml of sterile rabbit bile around the bile duct on the first 3 postoperative days or by dividing the hepatic duct of the right lateral lobe of the liver. All animals were killed on the i4th postoperative day and the bile duct was studied both radiologically and histologically. No abnormality was seen in the 2 groups subjected to trauma or pooled bile only. In the group which had both trauma and pooled bile i I out of i8 rabbits showed an abnormality of healing at the crush site.
The anatomical basis of transthoracic sympathectomy
H Ellis (Surgical Unit, Westminster Medical School, London) The sympathetic innervation to the upper limb is derived from the 2nd to 4th thoracic spinal segments with synapse stations in the 2nd to the 4th thoracic sympathetic ganglia. The conventional supraclavicular approach to the chain is technically An experimental evaluation of the'use of quite difficult and carries with it the very real risk of damage to the stellate ganglion with resultant synthetic materials in repair of the bili- Homer's syndrome. The transaxillary transpleural ary tract approach via the second intercostal space (originally C M Backhouse and K W Reynolds (Department of described by Hedley Atkins in I954; Lancet, I, 538) Anatomy, Charing Cross Hospital Medical School, provides an anatomically and technically simple acand Department of Surgery, Charing Cross Hospital, cess to the chain and is the method of choice in patients with Raynaud's disease and particularly with London) Previous experimental studies of bile duct sub- hyperhidrosis (excessive sweating) affecting the stitutes, such as autografts, heterografts, and syn- hands. Resection of the rib is not necessary and an thetic grafts, to repair or replace strictured or neo- excellent anatomical display of the chain as this lies plastic bile ducts have been discouraging owing to on the necks of the upper ribs can readily be achieved. fistula formation or obstruction. In this study two synthetic materials widely used as vascular pros- The anatomical crux of proximal gastric theses were assessed experimentally for biliary-tract vagotomy repair. Patches of either reinforced, expanded polytetra- M Hobsley (Middlesex Hospital, London) fluoroethylene (PTFE, Goretex) or knitted Dacron The anatomy of the vagus nerve is important in the (polyethylene terephthalate) were used to close el- operation of abdominal vagotomy for peptic ulcerliptical holes made in guineapig gallbladders. The ation. The essence of the operation is that the vagoanimals were killed at varying intervals and their tomy should be complete enough to reduce the gallbladders removed for examination. Thirty-two secretory ability of the stomach below a critica'l level, animals were used, half receiving PTFE and half thereby allowing the ulcer to heal. Evidence from 74 Dacron patches. Three early deaths occurred, all in unoperated ulcer cases and from I55 patients treated the PTFE group. By three weeks marginal mucosal for a duodenal ulcer by vagotomy established this overgrowth was seen on the inner surface of the critical level. Using Burge's intraoperative technique patches which did not progress further. Some later for demonstrating adequacy of vagotomy in terms specimens showed epithelium intermingled with and of the effect on gastric muscular tone, and checking outside the patches, marked differences being noted the results with postoperative acid studies, the imbetween the two groups. The comparative histo- portant points in the technical performance of proxi-
British Association of Clinical Anatomists mal gastric vagotomy were established. The most important step seems to be to denude the lowest 5 cm of the muscle wall of the oesophagus of all its investments. Results in 24 patients using these methods were described.
What is the function of the taeniae coli? A G Johnson (Department of Surgery, Charing Cross Hospital Medical School, London) Only primates, the horse, guineapig, and rabbit have taeniae coli like men. The taeniae are one-sixth shorter than the intestine, producing the characteristic haustrations; muscle fibres also pass to the circular muscle coat, making the taeniae a firm longitudinal cable against which it can pull. The number of haustrations may affect the streaming of the colonic contents (Findlay et al., Gut, 1974, I5, 207). The taeniae in rhesus monkeys are active 40o% of the time and activity is increased by feeding (Weisbrodt et al., Journal of Applied Physiology, 197I, 30, 276). Contraction of taenia increases depth of haustrations and delays colonic transit, this phenomenon being greatest in human diverticular disease. The effect of multiple transverse cuts of the two antimesenteric taeniae (taeniomyotomy) has been studied in rabbits and patients with diverticular disease. The haustrations spread out, the colon dilates, and the intraluminal response to stimuli is decreased. Healing of the cuts occurs first with granulation tissue followed by a thin layer of fibrous tissue. As this contracts and matures the intraluminal pressure may return towards preoperative levels.
Clearance of extravascular materials from the renal medulla D B Moffat (Department of Anatomy, University
College, Cardiff) Ferritin or Imferon (iron dextran) was introduced into the renal medulla in 50 Wistar rats by intravenous injection, by vesicoureteric reflux, or by direct microinjection into the papilla. Scattered clusters of iron-packed phagocytic cells were found in the outer medulla within 30 min of intravenous injection. These were usually in the vicinity of dilated vessels filled with blood. Many of the cells had ruptured, some were within the dilated vessels, and some appeared to be passing through the vessel wall. After direct injection into the papilla only a few iron-filled cells were seen at the site of the lesion, but these became more numerous near the
base of the papilla, where they appeared as longitudinal chains of cells between the tubules. After ferritin reflux a segmental lesion appeared after I-2 weeks similar to that produced by infection. This was the result of the protein nature of ferritin rather than its iron content, since Imferon reflux did not produce such a lesion. This work was supported by a grant from the Wellcome Trust.
The cremaster muscle and testicular descent K M Backhouse (Institute of Basic Medical Sciences, Royal College of Surgeons, London) The cremaster muscle has been reported quite erroneously from Hunter as being responsible for testicular descent and otherwise as being a derivative of the internal oblique muscle in a gubernacular and testicular heemiation of the anterior abdominal wall in the descent process. The development and adult anatomy of the cremaster muscle were described in man and compared with the situation found in certain other mammals, where it serves a comparable though sometimes more dynamic role. The development of the muscle in cryptorchism and ectopia testis was also considered.
The anatomy of the varicocoele in relation to subfertility J T Hill and N A Green (King's College Hospital, London, and Norfolk and Norwich Hospital, Norwich) Twenty-five patients with a clinical varicocoele were presented; I4 patients were subfertile. They were classified into 3 groups by venography of the left renal, internal spermatic, and cremasteric veins. Ten patients were grouped as having pure internal spermatic venous incompetence, 5 cremasteric venous incompetence, and 3 both internal spermatic and cremasteric venous incompetence. Seven patients could not be classified as having any venous incompetence despite having a clinical varicocoele. Subfertility was not found in patients with pure
cremasteric varicocoeles. Venous pressures were recorded in the internal spermatic and left renal veins of i6 patients. A raised left renal venous pressure was commonly associated with left internal spermatic venous incompetence. Internal spermatic and peripheral venous hormone measurements were recorded but were found to be unhelpful in the elucidation of the relationship between subfertility and varicocoele.