Congenital teratomas of the head and neck

OBJECTIVE

This article reviews teratomas, neoplasms composed of the three germinal layers of the embryo that form tissues foreign to the part in which they arise. These are most common in the sacrococcygeal region and are rare in the head and neck. In this region, major concerns are airway obstruction and cosmesis.

METHOD

Pathology records at two tertiary care paediatric hospitals were reviewed for diagnoses of head and neck teratomas. This revealed nine cases between 1983 and 1993, five males and four females. Two males were stillborn. Five were cervical, two were in the nasopharynx, and two were facial. The lesions were immature in two cases and mature in the remainder. All of the liveborn children underwent surgery within the first year of life, and only one required tracheotomy.

RESULTS

One child had recurrence of teratomatous tissue diagnosed with CT, which was treated surgically. The child has remained free of tumour for over 3 years. Pathogenesis, clinical appearance, diagnostic work-up, and currently accepted modes of therapy are reviewed.

Tonsillectomy: indications for referral by family physicians versus indications for surgery by otolaryngologists

OBJECTIVE

The purpose of this study was to compare reasons for family physician (FP) referral of children for tonsillectomy to the indications for this surgery used by otolaryngologists practising in the same region.

METHOD

A checklist-type survey was sent to a random sample of 300 FPs and all of the practising otolaryngologists in Nova Scotia in the spring of 1995.

RESULTS

There were significant differences between reasons for referral and indications for treatment in many areas, the most important of which was that over 60% of FPs referred cases because of parental insistence, while no surgeons operated for this reason. If inappropriate referrals are taken to be those for which no specialist intervention occurs, it appears that there is a significant number of referrals.

CONCLUSION

These results suggest that both FPs and parents require information about these common paediatric problems.

Detection of silent intervals between noises activating different perceptual channels: some properties of "central" auditory gap detection

This article describes four experiments on gap detection by normal listeners, with the general goal being to examine the consequences of using noises in different perceptual channels to delimit a silent temporal gap to be detected. In experiment 1, subjects were presented with pairs of narrow-band noise sequences. The leading element in each pair had a center frequency of 2 kHz and the trailing element's center frequency was parametrically varied. Gap detection thresholds became increasingly poor, sometimes by up to an order of magnitude, as the spectral disparity was increased between the noise bursts that marked the gap. These data suggested that gap-detection performance is impoverished when the underlying perceptual timing operation requires a comparison of activity in different perceptual channels rather than a discontinuity detection within a given channel. In experiment 2, we assessed the effect of leading-element duration in within-channel and between-channel gap detection tasks. Gap detection thresholds rose when the duration of the leading element was less than about 30 ms, but only in the between-channel case. In experiment 3, the gap-detection stimulus was redesigned so that we could probe the perceptual mechanisms that might be involved in stop consonant discrimination. The leading element was a wideband noise burst, and the trailing element was a 300-ms bandpassed noise centered on 1.0 kHz. The independent variable was the duration of the leading element, and the dependent variable was the smallest detectable gap between the elements. When the leading element was short in duration (5-10 ms), gap thresholds were close to 30 ms, which is close to the voice onset time that parses some voiced from unvoiced stop consonants. In experiment 4, the generality of the leading-element duration effect in between-channel gap detection was examined. Spectrally identical noises defining the leading and trailing edges of the gap were presented to the same or to different ears. There was a leading-element duration effect only for the between channel case. The mean gap threshold was again close to 30 ms for short leading-element durations. Taken together, the data suggest that gap detection requiring a temporal correlation of activity in different perceptual channels is a fundamentally different task to the discontinuity detection used to execute gap detection performance in the traditional, within-channel paradigm.

Cranial nerve defects in congenital facial palsy

METHODS

Cranial nerve defects were enumerated in 29 children with congenital facial palsy presenting for reanimation via chart review with a view to determining unaffected donor nerves. The literature was searched via Medline to reveal 186 additional case reports that were complete enough in their description to allow assessment of cranial nerve defects.

RESULTS

The group presenting for reanimation comprised 24 females and 5 males. All of the males had unilateral isolated facial nerve paralysis. Of the females, 9 had isolated unilateral palsy and 14 had bilateral palsy, and half of these were isolated. Six had bilateral abducens nerve palsy, fulfilling the original definition of Möbius syndrome. Of these, 3 had a right-sided hypoglossal weakness, one had a bilateral oculomotor palsy, and one had a bilateral trochlear palsy. One girl had bilateral facial and auditory involvement. The literature review revealed a group that was 60% male, with 85% having bilateral facial palsy. Abducens palsy was present in 68%, glossopharyngeal in 28%, hypoglossal in 26%, and oculomotor in 20%. The group was very heterogeneous in many ways.

CONCLUSIONS

There are many theories of pathogenesis of this syndrome. Isolated facial palsy is in concordance with previous findings of nerve lesions within the temporal bone. Multiple cranial nerve defects are more likely to have brainstem lesions, related to prenatal ischemic events. The cranial nerve least likely to be involved was the accessory nerve, suggesting that this may be a reliable donor for reanimation procedures.

Treatment and prevention of porcine proliferative enteropathy with oral tiamulin

The effect of an oral treatment or prevention programme, incorporating the antibiotic tiamulin, on the development of proliferative enteropathy in experimentally challenged pigs was studied. Twenty weaner pigs were challenged orally with a virulent inoculum of Lawsonia intracellularis strain LR189/5/83, a British isolate of the causative agent of porcine proliferative enteropathy, and seven control pigs were dosed with a buffer solution. Seven of the 20 challenged pigs were left untreated; they gained less weight than the controls and three of them developed mild to moderate diarrhoea two weeks after the challenge. All seven developed lesions, six visible grossly, of proliferative enteropathy, and numerous intracellular L intracellularis were detected in sections of the intestines examined three weeks after the challenge. To test a 'prevention' dosing strategy for tiamulin, six of the challenged pigs were dosed orally with 50 ppm tiamulin, incorporated in a 2 per cent stabilised premix, given from two days before the challenge until they were euthanased. To test a 'treatment' strategy, the remaining group of seven challenged pigs were dosed orally with 150 ppm tiamulin given in the premix from seven days after challenge until they were euthanased. All the control pigs and the 13 pigs treated with tiamulin, either before or after challenge, remained clinically normal and had no specific lesions of proliferative enteropathy in sections of the intestines examined post mortem.

Extremity gangrene in utero

A neonate with extremity gangrene resulting from intrauterine embolization of infarcted placental substances is discussed. This rare clinical entity is thought to be most commonly a manifestation of embolic phenomenon during maturation of the neonatal circulatory system. Management of neonatal gangrene is conservative, delaying amputation as long as possible since the line of demarcation tends to migrate distally. Evidence of multiple emboli should be carefully sought prior to definitive treatment.

Delayed rupture of the spleen and streptokinase therapy

Delayed rupture of the spleen is a rare but serious complication of blunt abdominal trauma. A 47-year-old woman with a history of fractured pelvis from a motor vehicle accident 6 months earlier presented with evidence of a myocardial infarction. Subsequent streptokinase administration was complicated by splenic rupture, which was managed by evacuation of the clotted blood and splenectomy. The patient made a complete recovery. The risk of splenic rupture and bleeding complications resulting from thrombolytic therapy for myocardial infarction is discussed, as are the controversy over whether delayed splenic rupture is a true diagnosis, the mechanism of rupture and the clues to impending rupture.

Blue rubber bleb nevus syndrome

Blue rubber bleb nevus syndrome, an uncommon condition, is manifested by gastrointestinal and skin hemangiomas and gastrointestinal hemorrhage causing anemia. The authors report a unique case of the syndrome in association with a congenital cardiac malformation. A 26-year-old woman presented with iron-deficiency anemia after the birth of her first child. She had a history of skin and gastrointestinal hemangiomas and tetralogy of Fallot. Endoscopy revealed multiple new intestinal hemangiomas, which were removed through enterotomies with resolution of the anemia. Iron therapy was prescribed, and her condition was stable at follow-up 5 years later.

Human bites to the hand

Human bites to the hand or penetrating injuries contaminated with saliva can be a source of aggressive infection and debilitating injury. These types of injuries may also be a mode for the transmission of disease, notably hepatitis B. Dental personnel have an increased risk of experiencing bite injuries and should understand the general principles of appropriate management. Staphylococcal or streptococcal species are often associated with infected bite injuries, and amoxicillin and clavulanate are currently advised for prophylaxis. Wound cleansing and careful monitoring, combined with appropriate prophylaxis, are the mainstays of treatment.

The behaviour of monoclonal antibodies in the First International Pig CD Workshop reacting with gamma delta/Null T lymphocytes in the blood of SLAb/b line pigs

Further studies were carried out on the monoclonal antibodies (mAbs) from the First International Swine CD Workshop which react with gamma delta Null T-lymphocytes, defined by the binding of mAb w020/141 (MAC320) as Swine Workshop Cluster number SWC6. Studies were also carried out on several other mAbs from the same workshop which identify other CD antigens, but whose binding is not restricted exclusively to gamma delta Null T-lymphocytes. The first group consists of 11 mAbs (w021, w022, w059-w065, w105 and w117) and the second group of 18 mAbs (w008, w026, w056, w067-w071, w080, w091-w094, w110, w111, w118, w119 and w121). All mAbs were characterised by binding to peripheral blood lymphocytes (PBL) from normal, sham-thymectomized (STx) and thymectomized (Tx) pigs of the Babraham SLAb/b line and by their overlap, using two-colour immunofluorescence with biotinylated mAb MAC320 (w020/141), which identifies all gamma delta Null cell T-lymphocytes and the Null cell subpopulation identified by MAC319 (w021). The Null cell-specific mAbs were also used in inhibition studies of MAC319 and MAC320 binding and by staining PBL with pairs of mAbs together with either MAC319 or MAC320. Based on these data we suggest a putative relationship of the Null cell subsets defined by these mAbs with each other.

The foot in ballet dancers: the importance of second toe length

Ballet dancers are prone to foot injuries. Our hypothesis was that the length of the second toe in relation to the big toe affected the distribution of stresses on the foot, correlating with calluses, injuries, and pain. Fifty-nine ballet dancers were examined for second toe length with respect to great toe, calluses, and metatarsophalangeal inflammation. Daily foot pain, limitation of work hours because of this, injuries, age, sex, and rank in the company were considered. The dancers' feet had an incidence of shorter, equal, or longer second toes which was comparable to a non-ballet-dancing cohort (N = 60). In female dancers (N = 34), total callus counts and pain scores were significantly lower in the group with shorter second toes versus those with equal or longer second toes. Counts were unrelated to age or rank. Longer second toes were related to hallux rigidus. Limitation of practice hours, ankle sprains, and foot/ankle fractures and sprains were comparable across the groups. The male dancers (N = 25) had significantly fewer calluses than did the women, but had equal pain scores and number of injuries. There were no significant differences among the males in total callus counts, pain scores, limitation of practice hours, or injuries between groups based on toe length, age, or rank. We conclude that there is no significantly more ideal pattern of toe lengths for male ballet dancers, but females with shorter second toes have fewer calluses and less daily foot pain. Those with a longer second toe had a higher incidence of hallux rigidus and correspondingly increased pain scores.

Gracilis donor site morbidity

Donor site morbidity in 104 cases of gracilis free tissue transfer was examined through a retrospective chart review and mail survey. Fifty-one females and 53 males with an average age of 23 years comprised the study group. Forty-three were under age 18. In-hospital donor site complications occurred in 10 patients. There was excessive pain in 4, wound infections in 3, hemorrhage in 2, and temporary nerve palsy in 1. Early complications were more common in the pediatric group. Sixty-two surveys were returned from patients detailing late complications where they graded parameters between 0 and 10 where 0 was "none" and 10 was "worst imaginable." The highest average score was 5.12 reported for noticeability of the scar. There was a significant difference between adults and children for sensitivity, tightness, notice-ability, and ugliness of the scar. More than half the respondents had no complaints about their donor site scar. Fifteen percent of patients reported temporary reduction of leg strength with a men duration of 6 months.

Sporotrichosis of the hand: an urban experience

Sporotrichosis is uncommon in Canadian urban centers. Lymphocutaneous and fixed cutaneous are the most common cutaneous forms of the disease, typically seen in the upper extremity in adult patients. History usually reveals a puncture injury contaminated with soil. Lesions are refractory to commonly used antibiotics. Cultures of biopsy specimens reliably grow the fungus Sporothrix schenkii. First line treatment is oral potassium iodide. We have reviewed a series of 7 cases from various Toronto teaching hospitals and compared them to the world literature.

Analyses of monoclonal antibodies reactive with porcine CD44 and CD45

Twenty-six monoclonal antibodies (mAbs), assigned to the CD44/CD45 section of the First International Swine CD Workshop, were compared for their reactivity against a selected group of target cells by one- and two-color flow cytometric analysis. Based on staining and reactivity patterns the 26 mAbs were assigned to six groups, group F1 mAbs were designated CD44 mAbs; and groups F2 and F3 as CD45 mAbs. With the information available, a CD designation could not be given to the mAbs in groups F4, F5 or F6 consisting of four, three and four mAbs each, respectively. The reactivity of all six mAbs in group F1 (MAC35, 25-32, PORC24A, H22A, BAG40A, and BAT31A) was blocked by soluble porcine CD44. One mAb in this group (MAC325) reacted with a cell surface protein with a molecular weight of 80 kDa and was designated as CD44; the other five mAbs were designated as wCD44 because no molecular weight was known. Blocking experiments utilizing a cross reactive anti-human CD44 (mAb Z062) allowed the definition of the wCD44a epitope recognized by mAbs PORC24A and H22A. The group F2 mAbs (74-9-3; MAC323; K252.1E4; and 2A5) were designated as CD45 based on their broad reactivity pattern with lymphoid and myeloid cells and their ability to immunoprecipitate three polypeptides with an apparent molecular weight of 226, 210 and 190 kDa. The F3 mAbs (MAC327; MAC326; 3a56 and -a2) were designated as CD45R based on their restricted reactivity against lymphoid and myeloid target cells, and their ability to immunoprecipitate either two polypeptides with an apparent molecular weight of 226 and 210 kDa (mAbs MAC327 and MAC326) or a single polypeptide with an apparent molecular weight of 210 kDa (mAbs-a2 and 3a56). Sequential immunoprecipitation analyses confirmed the relatedness of the F2 and F3 group mAbs. The work conducted for this first workshop led to the definition of six mAbs specific for CD44, four mAbs specific for CD45, and four mAbs specific for CD45R which should prove to be very valuable reagents for the study of the porcine immune system.

Monoclonal antibodies recognising differentiation antigens on porcine B cells

Nineteen monoclonal antibodies (mAbs) submitted to the porcine CD Workshop were analysed on porcine B cells from different lymphoid tissues by flow cytometry and immunohistochemistry. Six mAbs only bound to pig B cells and three of these were assigned cluster numbers, 76-7-4 (No. 001):CD1, K231-3B2 (No. 027):CD25 and CC51 (No. 100):CD21. Of the three remaining B cell positive mAbs, one was assigned to a swine cluster, CC55 (No. 101):SWC7, a second, LIG4 (No. 123), recognised cell surface IgM and the third, MUC106A (No. 072), remained unassigned.

Summary of first round cluster analysis: complete antibody panel

The reactivities of 141 monoclonal antibodies (mAbs) with 60 target cell types or lines were analysed by flow cytometry and the data subjected to statistical clustering. mAbs were assigned to 23 clusters by statistical similarity and information on specificity supplied by the contributor. Clustered mAbs were examined in more detail in the second round of workshop analyses.

Report on the behaviour of monoclonal antibodies in the First International Pig CD Workshop identifying the Null cell families

Clustering analyses were carried out on data from five independent laboratories testing 22 monoclonal antibodies (mAbs) reacting with CD2-sIg-lymphocytes on 14 pig blood and/or tissue lymphoid target cells using cytofluorometry. This was coupled with extensive further studies on blood lymphocytes from normal and thymectomised SLAb/b inbred pigs. These mAbs formed two groups: those mainly identifying the large blood-borne thymus-dependent Null T cells (N) and those reacting with tissue and a small number of blood-borne thymus-independent lymphocytes (N'). Based on their tissue cell reaction patterns, the 10 N' mAbs formed three main groups: N'1A and B; N'2A and B; and N'3. The 12N mAbs fell into four groups N4-N7; N6 was divided into subgroups A-D. One N' (032) and two N mAbs (010 and 063) were unclustered. Based on these data, swine workshop cluster numbers were designated to groups N5 (021, 022 and 059) as SWC4, N6 (061 and 117) as SWC5 and N7 (020 and 141) as SWC6, the latter exceptionally as a single antibody, MAC320, since it is the 'type' mAb identifying effectively all blood Null T lymphocytes. Future research and workshops will have to define with a wider range of techniques the relationships, molecular properties and functional roles of the several new, perhaps novel, antigens identified by this family of fascinating, as yet still poorly defined, mAbs.

Osteoarthritis of the thumb: clinical aspects and management

The wide range of motion of the thumb derives from the unusual nature of its carpometacarpal joint. Osteoarthritis is common in this joint. Patients may present with variable degrees of pain, reduction of thumb mobility, and joint deformity. Management is based on clinical assessment. Early disease is treated with rest, anti-inflammatory agents or analgesics, intraarticular steroid injections and splints. Since the course of osteoarthritis is often benign, avoiding early invasive treatment is important, except in the presence of proven anatomic deformity.

Extremity arteriovenous malformations: review of a series

OBJECTIVE

To examine the diagnosis and treatment of arteriovenous malformations in adults, because of the tendency of the condition to recur.

DESIGN

Chart and literature review.

SETTING

Three tertiary-care hospitals.

PATIENTS

Twelve adults with diffuse arteriovenous malformations of the extremities.

INTERVENTIONS

Surgery of embolotherapy.

MAIN OUTCOME MEASURE

Recurrence.

RESULTS

Of the 12 cases reviewed, the arteriovenous malformations recurred in 8 patients; 2 of these were well, 6 months and 2 years after a second or third treatment. Two others were well, 2 months and 5 years after surgery or embolotherapy. One pregnant woman, whose case is described in detail, received no treatment, and her arteriovenous malformation diminished in size after her child was born. The outcome in the last patient is unknown.

CONCLUSION

Diffuse arteriovenous malformations recur after ablative treatment.

Facial fractures

Emergency room physicians frequently see facial fractures that can have serious consequences for patients if mismanaged. This article reviews the signs, symptoms, imaging techniques, and general modes of treatment of common facial fractures. It focuses on fractures of the mandible, zygomaticomaxillary region, orbital floor, and nose.

Expression on porcine gamma delta lymphocytes of a phylogenetically conserved surface antigen previously restricted in expression to ruminant gamma delta T lymphocytes

A 180,000 MW molecule has been identified on porcine leucocytes that is the homologue of the 215,000/300,000 MW WC1 (T19) leucocyte antigen previously considered to be restricted to ruminants. In ruminants the WC1 molecule is expressed by a T-cell subpopulation that is CD2-CD4-CD8-CD5+ and that is gamma delta T-cell receptor positive (TcR+). In pigs, the 180,000 MW molecule, identified by a new monoclonal antibody CC101, is expressed by a gamma delta TcR+ T-cell subpopulation that is also CD2-CD4-CD8-. The p180+ cells are a major T-cell subpopulation comprising approximately 40% of the peripheral blood mononuclear cells from 6-9-month-old pigs. Expression of p180 identifies the majority of the CD2-CD4-CD8- T cells in porcine blood. The p180+ T cells have a distribution in lymphoid tissues that is distinct from that of T cells that express the CD2, CD4 or CD8 molecules. They are evident particularly in the thymic medulla, the epithelium, lamina propria and interfollicular areas of the small intestine, and the superficial dermis of the skin, but largely absent from conventional T-dependent areas of secondary lymphoid tissue.