- Email: [email protected]
Case report: The treatment of a chronic parotid cutaneous fistula by the injection of a solution of lipiodol with cyanoacrylate
616
CLINICAL RADIOLOGY
was demonstrated indicating fibrosis. The expiratory TSS images demonstrated bronchiectasis and a mosaic pattern of lung attenuation consistent with air trapping (Fig~ la). The 5, 8 and 10 mm thick slab expiratory MinlPs demonstrated a mosaic pattern of lung attenuation with greater conspicuity than their integral images (Fig. 1) The patient underwent a sequential double lung transplant. Pathology of the right and left lungs revealed diffuse suppurative bronchiectasis and post bronchiectatic bronchiolitis consistent with cystic fibrosis.
DISCUSSION Cystic fibrosis is an autosomal recessive disorder, and the product of the gene results in an epithelial cell membrane chloride channel defect [2]. The abnormally low water content of mucus leads to blockage of bronchioles and bronchi resulting in infection and inflammation which progresses to bronchiectasis. The clinical course of bronchiectasis is interspersed with episodic acute exacerbations of pulmonary infection leading to peribronchial fibrosis and progressive loss of pulmonary function and respiratory failure. To treat this, double lung transplantation has been successful in cystic fibrosis patients with end stage lung disease [3]. On high resolution CT scans, cystic fibrosis is manifest as bronchiectasis and a mosaic pattern of lung attenuation which reflects small airways disease and air trapping. Expiratory high resolution CT scans accentuate the mosaic pattern of lung attenuation caused by air trapping [4,5], indeed, the expiratory high resolution CT scan is necessary to help to differentiate among different causes of a mosaic pattern of lung attenuation [4]. Air trapping is accentuated by expiration because the areas of decreased attenuation on the CT scan remain unchanged in volume and attenuation, whereas the uninvolved lung shows a homogenous increase in attenuation [5,6]. MinIP images accentuate the differences in lung attenuation due to the inherent high-contrast resolution. As expiration accentuates air trapping, expiratory MinlP images are potentially very useful to demonstrate the mosaic pattern of lung attenuation caused by small airways disease. Air trapping has been demonstrated following forced expiration of subjects with normal pulmonary function [7,8]. Up to 25% of the cross-sectional area of one section of lung has been shown to demonstrate air-trapping in normal subjects [7], in our patient approximately 70% and 60% of the cross-sectional area of the
right and left lung, respectively, demonstrated decreased attenuation suggesting extensive air trapping. The extent of the air trapping in our case is regarded as pathological. Subjectively, comparing the 5, 8 and 10mm thick slab expiratory MinIP images (Fig. lb, c), the mosaic pattern of lung attenuation is equally well demonstrated, even though the degree of high signal intensity structure suppression is least on the 5 mm thick slab EMinIP. In patients with suspected small airways disease a 5 mm thick slab expiratory MinlP image would be advantageous, as patients with dyspnoea can perform a five second easier than a 10 s breath-hold. Also the use of 5-mm thick slab MinIPs reduces the radiation dose, compared to 10-mm thick slab MinIPs. In conclusion, expiratory MinIP images improve the conspicuity of a mosaic pattern of lung attenuation in cystic fibrosis, it may be useful in other patients where air trapping is a feature of lung disease. Acknowledgement.The authors would like to thank Rose Baldwin for her assistance in the preparation of this manuscript.
REFERENCES 1 Bhalla M, Naidich DP, McGinness G, Grnden JF, Leitman BS, McCauley DI. Diffuse lung disease: Assessment with helical CT - Preliminary observations of the role of maximum and minimum intensity projection images. Radiology 1996;200:341-347. 2 Welsh MJ, Tsui L, Boat FT, Beaudet AL. Cystic fibrosis. In: Scriver CR, Beandet AL, Sly WS, Valle D, eds. The Metabolic and Molecular Basis oflnherited Disease. New York: McGraw-Hill, 1995, 3799-3876. 3 Hasan A, Corris PA, Healy M e t al. Bilateral sequential lung transplantation for end stage septic lung disease. Thorax 1995;50:565-566. 4 Stern EJ, Swensen SJ, Hartman TE, Frank MS. CT mosaic pattern of lung attenuation: Distinguishing different causes. American Journal of Roentgenology 1995;165:813-816. 5 Stern EJ, Frank MS. Small-airway diseases of the lungs: findings at expiratory CT. American Journal of Roentgenology 1994;163:37-41. 6 Muller NL, Miller RR. Diseases of the bronchioles: CT and histopathologic findings. Radiology 1995;196:3-12. 7 Webb WR, Stern EJ, Kanth N, Gamsu G. Dynamic pulmonary CT: Findings in healthy adult men. Radiology 1993; 186:117-124. 8 Park CS, Muller NL, Worthy SA, Kim JS, Awadh N, Fitzgerald M. Airway obsuuction in asthmatic and healthy individuals: Inspiratory and expiratory thin-section CT findings. Radiology 1997; 203:361-367.
Clinical Radiology (1998) 53, 616-618
Case Report: The Treatment of a Chronic Parotid Cutaneous Fistula by the Injection of a Solution of Lipiodol With Cyanoacrylate A. J. MARCUS and N. A. NASSER*
Departments of Scientific Services and *Oral Surgery, Wellhouse Trust, Barrier, Hertfordshire, UK Superficial parotidectomy can rarely be complicated by a parotid cutaneous fistula from the deep lobe of the gland. The fistula is usually treated by excision of the deep lobe, which carries a risk of facial nerve damage. We present a
case successfully treated by injecting the fistula with a solution of lipiodol combined with cyanoacrylate.
Correspondence to: Dr A. J. Marcus, Department of Radiology, Edgware General Hospital, Edgware, Middlesex HA8 0AD, UK.
A 59-year-old man, had a right superficial parotidectomy with duct ligation for chronic sialadentis in November 1991. The operation was
CASE REPORT
9 1998 The Royal College of Radiologists, ClinicalRadiology, 53, 616-618.
CASEm~PORTS
617
Fig. 1 - Fistulogram shows connection with the deep lobe of the parotid gland and clearly demonstrates its radicles.
Fig. 2 - Repeat fistulogram 4 months later shows that the main duct is patent but there is poor tilling of the parotid gland radicles.
complicated by a parotid fistula. The leak, which became worse on eating, necessitated him dining with a towel around his neck. This was not only inconvenient but socially embarrassing causing excoriation around the orifice of the fistula. In August 1992, he was referred for radiotherapy receiving 2000 cGy in 10 fractions over 14 days. The treatment was completed in October 1992. There was no response to the radiation. In January 1995, the tympanic nerve of Jacobson was divided in two places. Unfortunately, this was also ineffective. In March 1995, a fistulogram demonstrated that the tract connected with the deep lobe of the parotid and clearly filled its radicles (Fig. 1). The patient was by now resigned to excision of the deep lobe, with its inherent risk to the facial nerve. He was offered an aitemative treatment of injection of the gland with cyanoacrylate (superglue) via the fistula tract in an effort to ablate the deep lobe of the gland. In June 1995, a solution of lipiodol and cyanoacrylate in a ratio of 1:4 was injected into the gland via an 18 G Rabinov parotid sialography catheter inserted into the fistula. There was immediate reduction in the secretion and the patient felt some discomfort in the gland. He was allowed to go home on antibiotics and analgesics (amoxycillin 250 g tds for 5 days, and voltarol 50mg bd). Unfortunately, he failed to return for his outpatient appointment the following week and was not seen until 10 days later. He had symptoms compatible with parotiditis and pus was milked out of the fistula. The organisms cultured were Moraxella catarrhalis and a scanty growth of Pseudomonas s.p. Both were sensitive to ciprofloxacin. The infection settled with this treatment and the fistula secretions were reported by the patient to be greatly reduced. In September 1995, a repeat fistulogram demonstrated that the main duct was patent but there was poor filling of the parotid gland's radicles (Fig. 2). The duct was again injected with 0.5ml of a 1:1 solution of lipiodol to cyanoacrylate (Fig. 3). The patient found there was less discomfort on this occasion and he was given a 3-week course of antibiotic cover (trimethoprim bd 500 mg). On review 1 week later, he reported reduction of the secretion, which after a further 6 weeks was minimal and after another 3 months had almost totally ceased. Stimulation of the gland failed to demonstrate any leak and the plug of superglue had been extruded from the tract. The patient's excoriation around the fistula had resolved and the fistula orifice was now only just visible.
Fig. 3 - Injection of gland with a l: l solution of lipiodol to cyanoacrylate.
DISCUSSION Parotid cutaneous fistulae are a well recognized complication of superficial parotidectomy. The symptoms are due to complications from the persistent leakage of saliva. The source of the saliva is the deep lobe of the parotid gland which usually atrophies after surgery when its duct is tied. Rarely the deep lobe fails to atrophy and a fistula develops. In the unpublished series by the co-author (NN) of 150 cases of superficial parotidectomy, performed for tumour as well as inflammation, this case was the only one complicated by chronic fistula formation. Wax et al. [1] found that in a series of 106 patients postoperative fistulae occurred in 14% of cases overall but in 45% of patients who were operated on for chronic sialadenitis. Another 9 1998 The Royal College of Radiologists, Clinical Radiology, 53, 616-618.
paper [2] reported two patients with chronic salivary fistulae out of 21 patients operated on for chronic sialadenitis. Treatment of a fistula is difficult. It may resolve itself in time or with compressive bandage therapy. Bandage therapy appeared to be successful in all the cases reported by Wax et al. [1]. Therapy is usually directed at the deep lobe of the parotid gland in an effort to cause it to atrophy. This may be achieved by irradiation [3]. If this fails, then interruption of its parasympathetic stimulation can be achieved by division of Jacobson's nerve as it passes through the middle ear. Theoretically this would appear to be of value but I have seen no recorded cases where it has been found to be successful. There has recently been a report of the successful treatment of a fistula by the therapeutic action of octreotide [4]. Usually, further surgery necessitating the resection of the deep lobe of the parotid gland is necessary, with risk of damage to the facial nerve [5]. To avoid further surgery, a solution of lipiodol to cyanoacrylate in a ratio 1:4 was injected into the gland through the fistula. The agent, which polymerizes on contact with an electrolytic solution, in this case saliva, causes an exothermic reaction. The intention was for the agent to solidify in the alveoli, and then, by a combination of the exothermic reaction and alveolar obstruction, initiate an inflammatory reaction that would lead to atrophy of the gland. There was immediate improvement after the first injection and the patient was able to confirm the presence of the agent within the gland, as he described discomfort in his face. Prophylatic antibiotic cover was given, but unfortunately this was discontinued too quickly and infection occurred. This infection responded to antibiotics.
6 18
CLINICAL RADIOLOGY
The dilution of the cyanoacrylate to lipiodol was altered to a 1:1 dilution on the second injection. This was for a number of reasons. Polymerization is slowed down by the presence of the lipiodol and this allows more time for the solution to reach the alveoli, the polymerization reaction is less intense, thus causing less discomfort. In addition, the solution would be more radio-opaque [6]. The planning fistulogram, prior to the second injection of cyanoacrylate, demonstrated that the main duct was open and there had been pruning of the glandular tree. This confirmed that the mechanism of action of the cyanoacrylate was at the alveolar level. A repeat injection of a solution of 1:1 lipiodol to cyanoacrylate was performed which initially appeared to stop the secretions, although 7 days later the patient described an overall reduction of 50%. Four months later he reported an almost complete stoppage of the secretion. Stimulation of the gland failed to demonstrate any leak and it was thought possible that the moisture reported by the patient was due to Frey's syndrome. The patient was satisfied by the outcome of the treatment.
Acknowledgements. We would like to thank Mrs J. S. Marcus and Mrs B. J. Thompson for their help in preparing the manuscript.
REFERENCES 1 Wax M, Tarshis L. Post-parotidectomy fistula. Journal of Otolaryngology 1991;20:10-13. 2 Schultz PW. Subtotal parotidectomy in the treatment of chronic sialadenitis. Annals of Plastic Surgery 1983;II:459-461. 3 Shimm DS, Berk FK, Tilsner T et aL Low dose radiation therapy for benign salivary disorders. American Journal of Clinical Oncology 1992;15:76-78. 4 Spinnell C, Ricci E, Berti P e t al. Postoperative salivary fistula: Therapeutic action of octreotide. Surgery 1995;117:117-118. 5 Rintoul RF (ed). Farquarharson's Textbook of Operative Surgery, 6th edn. Edinburgh: Churchill Livingstone, 1978, 407-408. 6 Stoesslein FL, Ditscherlein G, Tomaniuk PA. Experimental studies on new liquid embolization mixtures (histoacryl-lipiodol, histoacrylpanthopaque). Cardiovascular and lnterventional Radiology 1982;5: 264-267.
Clinical Radiology (1998) 53, 618-619
Case Report: Femoral Hernia Causing Small Bowel Obstruction Ultrasound Diagnosis W. K. LOFTUS, F. M HEWITT* and O. METREWELI
Departments of Diagnostic Radiology and Organ Imaging and *Surgery, Prince of Wales Hospital, Chinese University of Hong Kong, Shatin, N.T. Hong Kong The diagnosis of femoral hernia is usually made clinically. Other than confirming small bowel obstruction, which is often a presenting feature, radiology has a little-accepted role despite the known difficulties in diagnosis. We report a case where ultrasound clearly demonstrated the hernial sac in a patient in whom the diagnosis was uncertain. Femoral hernia is the second commonest groin hernia after inguinal hernia but is less likely to be symptomatic and patients may be unaware of it until strangulation occurs (this is more common than with inguinal hernia). It typically presents as a lump lateral and inferior to the pubic tubercle but, if large, may extend superiorly and simulate an inguinal hernia. Other differential diagnoses include lymphadenopathy, femoral artery pseudoaneurysm, lipoma and saphena varix [1]. Less than two-thirds of femoral hernias are correctly diagnosed before hospital admission and over 10% are only diagnosed at laparotomy [2,3]. Despite emphasizing the difficulties in clinical diagnosis, recent surgical articles make no mention of the role of radiology in this condition [2,4]. However, there are several references in non-English language journals which refer to the use of ultrasound (US) for diagnosis of femoral hernia. In a German case report [5] the authors recommend the use of US in investigation of groin lumps and present a case of femoral hernia diagnosed by US. The only recent English Correspondence to: Dr W. K. Lotus, Department of Diagnostic Radiology and Organ Imaging, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, N.T. Hong Kong.
language article [6] on radiology in the diagnosis of femoral hernia concerns herniography alone and does not mention US. CASE REPORT The patient was an 87-year-old man who presented with a 2-day history of abdominal distention, vomiting and constipation. He had multiple medical problems including ischaemic heart disease with cardiac failure and had undergone abdominal surgery in his youth. On examination he was shocked and his abdomen was distended with visible peristalsis. There was a 4-cm non-tender mobile mass in the right groin. A plain abdominal film showed evidence of a small bowel obstruction. The groin mass was not typical of a hernia and the bowel obstruction could have been related to the previous surgery. Further imaging was requested and an ultrasound of the right groin was performed using a 10MHz transducer (HDI 3000, ATL, Bothell, WA). This showed the groin mass to be a loop of peristaltic bowel (Fig. 1). Superiorly, and medial to the femoral vessels, the loop narrowed to a small diameter neck (Fig. 2) which was contiguous with a loop of dilated small bowel within the abdomen. A diagnosis of femoral hernia was made. The patient was stabilized and at operation, via a transinguinal approach, the right femoral hernia was confirmed. A knuckle of small bowel of doubtful viability was found within it. A limited resection was done and the hernia was repaired. Postoperatively, the patient made an uneventful recovery.
DISCUSSION The US diagnosis of a femoral hernia as the cause of the small bowel obstruction in this case allowed the limited surgical approach required for its treatment and avoided an 9 1998 The Royal College of Radiologists, ClinicalRadiology, 53, 618-619.
CLINICAL RADIOLOGY
was demonstrated indicating fibrosis. The expiratory TSS images demonstrated bronchiectasis and a mosaic pattern of lung attenuation consistent with air trapping (Fig~ la). The 5, 8 and 10 mm thick slab expiratory MinlPs demonstrated a mosaic pattern of lung attenuation with greater conspicuity than their integral images (Fig. 1) The patient underwent a sequential double lung transplant. Pathology of the right and left lungs revealed diffuse suppurative bronchiectasis and post bronchiectatic bronchiolitis consistent with cystic fibrosis.
DISCUSSION Cystic fibrosis is an autosomal recessive disorder, and the product of the gene results in an epithelial cell membrane chloride channel defect [2]. The abnormally low water content of mucus leads to blockage of bronchioles and bronchi resulting in infection and inflammation which progresses to bronchiectasis. The clinical course of bronchiectasis is interspersed with episodic acute exacerbations of pulmonary infection leading to peribronchial fibrosis and progressive loss of pulmonary function and respiratory failure. To treat this, double lung transplantation has been successful in cystic fibrosis patients with end stage lung disease [3]. On high resolution CT scans, cystic fibrosis is manifest as bronchiectasis and a mosaic pattern of lung attenuation which reflects small airways disease and air trapping. Expiratory high resolution CT scans accentuate the mosaic pattern of lung attenuation caused by air trapping [4,5], indeed, the expiratory high resolution CT scan is necessary to help to differentiate among different causes of a mosaic pattern of lung attenuation [4]. Air trapping is accentuated by expiration because the areas of decreased attenuation on the CT scan remain unchanged in volume and attenuation, whereas the uninvolved lung shows a homogenous increase in attenuation [5,6]. MinIP images accentuate the differences in lung attenuation due to the inherent high-contrast resolution. As expiration accentuates air trapping, expiratory MinlP images are potentially very useful to demonstrate the mosaic pattern of lung attenuation caused by small airways disease. Air trapping has been demonstrated following forced expiration of subjects with normal pulmonary function [7,8]. Up to 25% of the cross-sectional area of one section of lung has been shown to demonstrate air-trapping in normal subjects [7], in our patient approximately 70% and 60% of the cross-sectional area of the
right and left lung, respectively, demonstrated decreased attenuation suggesting extensive air trapping. The extent of the air trapping in our case is regarded as pathological. Subjectively, comparing the 5, 8 and 10mm thick slab expiratory MinIP images (Fig. lb, c), the mosaic pattern of lung attenuation is equally well demonstrated, even though the degree of high signal intensity structure suppression is least on the 5 mm thick slab EMinIP. In patients with suspected small airways disease a 5 mm thick slab expiratory MinlP image would be advantageous, as patients with dyspnoea can perform a five second easier than a 10 s breath-hold. Also the use of 5-mm thick slab MinIPs reduces the radiation dose, compared to 10-mm thick slab MinIPs. In conclusion, expiratory MinIP images improve the conspicuity of a mosaic pattern of lung attenuation in cystic fibrosis, it may be useful in other patients where air trapping is a feature of lung disease. Acknowledgement.The authors would like to thank Rose Baldwin for her assistance in the preparation of this manuscript.
REFERENCES 1 Bhalla M, Naidich DP, McGinness G, Grnden JF, Leitman BS, McCauley DI. Diffuse lung disease: Assessment with helical CT - Preliminary observations of the role of maximum and minimum intensity projection images. Radiology 1996;200:341-347. 2 Welsh MJ, Tsui L, Boat FT, Beaudet AL. Cystic fibrosis. In: Scriver CR, Beandet AL, Sly WS, Valle D, eds. The Metabolic and Molecular Basis oflnherited Disease. New York: McGraw-Hill, 1995, 3799-3876. 3 Hasan A, Corris PA, Healy M e t al. Bilateral sequential lung transplantation for end stage septic lung disease. Thorax 1995;50:565-566. 4 Stern EJ, Swensen SJ, Hartman TE, Frank MS. CT mosaic pattern of lung attenuation: Distinguishing different causes. American Journal of Roentgenology 1995;165:813-816. 5 Stern EJ, Frank MS. Small-airway diseases of the lungs: findings at expiratory CT. American Journal of Roentgenology 1994;163:37-41. 6 Muller NL, Miller RR. Diseases of the bronchioles: CT and histopathologic findings. Radiology 1995;196:3-12. 7 Webb WR, Stern EJ, Kanth N, Gamsu G. Dynamic pulmonary CT: Findings in healthy adult men. Radiology 1993; 186:117-124. 8 Park CS, Muller NL, Worthy SA, Kim JS, Awadh N, Fitzgerald M. Airway obsuuction in asthmatic and healthy individuals: Inspiratory and expiratory thin-section CT findings. Radiology 1997; 203:361-367.
Clinical Radiology (1998) 53, 616-618
Case Report: The Treatment of a Chronic Parotid Cutaneous Fistula by the Injection of a Solution of Lipiodol With Cyanoacrylate A. J. MARCUS and N. A. NASSER*
Departments of Scientific Services and *Oral Surgery, Wellhouse Trust, Barrier, Hertfordshire, UK Superficial parotidectomy can rarely be complicated by a parotid cutaneous fistula from the deep lobe of the gland. The fistula is usually treated by excision of the deep lobe, which carries a risk of facial nerve damage. We present a
case successfully treated by injecting the fistula with a solution of lipiodol combined with cyanoacrylate.
Correspondence to: Dr A. J. Marcus, Department of Radiology, Edgware General Hospital, Edgware, Middlesex HA8 0AD, UK.
A 59-year-old man, had a right superficial parotidectomy with duct ligation for chronic sialadentis in November 1991. The operation was
CASE REPORT
9 1998 The Royal College of Radiologists, ClinicalRadiology, 53, 616-618.
CASEm~PORTS
617
Fig. 1 - Fistulogram shows connection with the deep lobe of the parotid gland and clearly demonstrates its radicles.
Fig. 2 - Repeat fistulogram 4 months later shows that the main duct is patent but there is poor tilling of the parotid gland radicles.
complicated by a parotid fistula. The leak, which became worse on eating, necessitated him dining with a towel around his neck. This was not only inconvenient but socially embarrassing causing excoriation around the orifice of the fistula. In August 1992, he was referred for radiotherapy receiving 2000 cGy in 10 fractions over 14 days. The treatment was completed in October 1992. There was no response to the radiation. In January 1995, the tympanic nerve of Jacobson was divided in two places. Unfortunately, this was also ineffective. In March 1995, a fistulogram demonstrated that the tract connected with the deep lobe of the parotid and clearly filled its radicles (Fig. 1). The patient was by now resigned to excision of the deep lobe, with its inherent risk to the facial nerve. He was offered an aitemative treatment of injection of the gland with cyanoacrylate (superglue) via the fistula tract in an effort to ablate the deep lobe of the gland. In June 1995, a solution of lipiodol and cyanoacrylate in a ratio of 1:4 was injected into the gland via an 18 G Rabinov parotid sialography catheter inserted into the fistula. There was immediate reduction in the secretion and the patient felt some discomfort in the gland. He was allowed to go home on antibiotics and analgesics (amoxycillin 250 g tds for 5 days, and voltarol 50mg bd). Unfortunately, he failed to return for his outpatient appointment the following week and was not seen until 10 days later. He had symptoms compatible with parotiditis and pus was milked out of the fistula. The organisms cultured were Moraxella catarrhalis and a scanty growth of Pseudomonas s.p. Both were sensitive to ciprofloxacin. The infection settled with this treatment and the fistula secretions were reported by the patient to be greatly reduced. In September 1995, a repeat fistulogram demonstrated that the main duct was patent but there was poor filling of the parotid gland's radicles (Fig. 2). The duct was again injected with 0.5ml of a 1:1 solution of lipiodol to cyanoacrylate (Fig. 3). The patient found there was less discomfort on this occasion and he was given a 3-week course of antibiotic cover (trimethoprim bd 500 mg). On review 1 week later, he reported reduction of the secretion, which after a further 6 weeks was minimal and after another 3 months had almost totally ceased. Stimulation of the gland failed to demonstrate any leak and the plug of superglue had been extruded from the tract. The patient's excoriation around the fistula had resolved and the fistula orifice was now only just visible.
Fig. 3 - Injection of gland with a l: l solution of lipiodol to cyanoacrylate.
DISCUSSION Parotid cutaneous fistulae are a well recognized complication of superficial parotidectomy. The symptoms are due to complications from the persistent leakage of saliva. The source of the saliva is the deep lobe of the parotid gland which usually atrophies after surgery when its duct is tied. Rarely the deep lobe fails to atrophy and a fistula develops. In the unpublished series by the co-author (NN) of 150 cases of superficial parotidectomy, performed for tumour as well as inflammation, this case was the only one complicated by chronic fistula formation. Wax et al. [1] found that in a series of 106 patients postoperative fistulae occurred in 14% of cases overall but in 45% of patients who were operated on for chronic sialadenitis. Another 9 1998 The Royal College of Radiologists, Clinical Radiology, 53, 616-618.
paper [2] reported two patients with chronic salivary fistulae out of 21 patients operated on for chronic sialadenitis. Treatment of a fistula is difficult. It may resolve itself in time or with compressive bandage therapy. Bandage therapy appeared to be successful in all the cases reported by Wax et al. [1]. Therapy is usually directed at the deep lobe of the parotid gland in an effort to cause it to atrophy. This may be achieved by irradiation [3]. If this fails, then interruption of its parasympathetic stimulation can be achieved by division of Jacobson's nerve as it passes through the middle ear. Theoretically this would appear to be of value but I have seen no recorded cases where it has been found to be successful. There has recently been a report of the successful treatment of a fistula by the therapeutic action of octreotide [4]. Usually, further surgery necessitating the resection of the deep lobe of the parotid gland is necessary, with risk of damage to the facial nerve [5]. To avoid further surgery, a solution of lipiodol to cyanoacrylate in a ratio 1:4 was injected into the gland through the fistula. The agent, which polymerizes on contact with an electrolytic solution, in this case saliva, causes an exothermic reaction. The intention was for the agent to solidify in the alveoli, and then, by a combination of the exothermic reaction and alveolar obstruction, initiate an inflammatory reaction that would lead to atrophy of the gland. There was immediate improvement after the first injection and the patient was able to confirm the presence of the agent within the gland, as he described discomfort in his face. Prophylatic antibiotic cover was given, but unfortunately this was discontinued too quickly and infection occurred. This infection responded to antibiotics.
6 18
CLINICAL RADIOLOGY
The dilution of the cyanoacrylate to lipiodol was altered to a 1:1 dilution on the second injection. This was for a number of reasons. Polymerization is slowed down by the presence of the lipiodol and this allows more time for the solution to reach the alveoli, the polymerization reaction is less intense, thus causing less discomfort. In addition, the solution would be more radio-opaque [6]. The planning fistulogram, prior to the second injection of cyanoacrylate, demonstrated that the main duct was open and there had been pruning of the glandular tree. This confirmed that the mechanism of action of the cyanoacrylate was at the alveolar level. A repeat injection of a solution of 1:1 lipiodol to cyanoacrylate was performed which initially appeared to stop the secretions, although 7 days later the patient described an overall reduction of 50%. Four months later he reported an almost complete stoppage of the secretion. Stimulation of the gland failed to demonstrate any leak and it was thought possible that the moisture reported by the patient was due to Frey's syndrome. The patient was satisfied by the outcome of the treatment.
Acknowledgements. We would like to thank Mrs J. S. Marcus and Mrs B. J. Thompson for their help in preparing the manuscript.
REFERENCES 1 Wax M, Tarshis L. Post-parotidectomy fistula. Journal of Otolaryngology 1991;20:10-13. 2 Schultz PW. Subtotal parotidectomy in the treatment of chronic sialadenitis. Annals of Plastic Surgery 1983;II:459-461. 3 Shimm DS, Berk FK, Tilsner T et aL Low dose radiation therapy for benign salivary disorders. American Journal of Clinical Oncology 1992;15:76-78. 4 Spinnell C, Ricci E, Berti P e t al. Postoperative salivary fistula: Therapeutic action of octreotide. Surgery 1995;117:117-118. 5 Rintoul RF (ed). Farquarharson's Textbook of Operative Surgery, 6th edn. Edinburgh: Churchill Livingstone, 1978, 407-408. 6 Stoesslein FL, Ditscherlein G, Tomaniuk PA. Experimental studies on new liquid embolization mixtures (histoacryl-lipiodol, histoacrylpanthopaque). Cardiovascular and lnterventional Radiology 1982;5: 264-267.
Clinical Radiology (1998) 53, 618-619
Case Report: Femoral Hernia Causing Small Bowel Obstruction Ultrasound Diagnosis W. K. LOFTUS, F. M HEWITT* and O. METREWELI
Departments of Diagnostic Radiology and Organ Imaging and *Surgery, Prince of Wales Hospital, Chinese University of Hong Kong, Shatin, N.T. Hong Kong The diagnosis of femoral hernia is usually made clinically. Other than confirming small bowel obstruction, which is often a presenting feature, radiology has a little-accepted role despite the known difficulties in diagnosis. We report a case where ultrasound clearly demonstrated the hernial sac in a patient in whom the diagnosis was uncertain. Femoral hernia is the second commonest groin hernia after inguinal hernia but is less likely to be symptomatic and patients may be unaware of it until strangulation occurs (this is more common than with inguinal hernia). It typically presents as a lump lateral and inferior to the pubic tubercle but, if large, may extend superiorly and simulate an inguinal hernia. Other differential diagnoses include lymphadenopathy, femoral artery pseudoaneurysm, lipoma and saphena varix [1]. Less than two-thirds of femoral hernias are correctly diagnosed before hospital admission and over 10% are only diagnosed at laparotomy [2,3]. Despite emphasizing the difficulties in clinical diagnosis, recent surgical articles make no mention of the role of radiology in this condition [2,4]. However, there are several references in non-English language journals which refer to the use of ultrasound (US) for diagnosis of femoral hernia. In a German case report [5] the authors recommend the use of US in investigation of groin lumps and present a case of femoral hernia diagnosed by US. The only recent English Correspondence to: Dr W. K. Lotus, Department of Diagnostic Radiology and Organ Imaging, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, N.T. Hong Kong.
language article [6] on radiology in the diagnosis of femoral hernia concerns herniography alone and does not mention US. CASE REPORT The patient was an 87-year-old man who presented with a 2-day history of abdominal distention, vomiting and constipation. He had multiple medical problems including ischaemic heart disease with cardiac failure and had undergone abdominal surgery in his youth. On examination he was shocked and his abdomen was distended with visible peristalsis. There was a 4-cm non-tender mobile mass in the right groin. A plain abdominal film showed evidence of a small bowel obstruction. The groin mass was not typical of a hernia and the bowel obstruction could have been related to the previous surgery. Further imaging was requested and an ultrasound of the right groin was performed using a 10MHz transducer (HDI 3000, ATL, Bothell, WA). This showed the groin mass to be a loop of peristaltic bowel (Fig. 1). Superiorly, and medial to the femoral vessels, the loop narrowed to a small diameter neck (Fig. 2) which was contiguous with a loop of dilated small bowel within the abdomen. A diagnosis of femoral hernia was made. The patient was stabilized and at operation, via a transinguinal approach, the right femoral hernia was confirmed. A knuckle of small bowel of doubtful viability was found within it. A limited resection was done and the hernia was repaired. Postoperatively, the patient made an uneventful recovery.
DISCUSSION The US diagnosis of a femoral hernia as the cause of the small bowel obstruction in this case allowed the limited surgical approach required for its treatment and avoided an 9 1998 The Royal College of Radiologists, ClinicalRadiology, 53, 618-619.