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Biomedical subjects

N F Jones

Publications and source records attributed to N F Jones.

At least 73 records · Page 4Linked to original sources
PubMed1992

Microvascular free tissue transfer for reconstruction of head and neck cancer defects.

Over the last 10 years, microvascular free tissue transfer techniques have broadened the range of the head and neck surgeon, allowing for successful reconstruction of extensive curative extirpations in one operation with minimal morbidity. Success rates of more than 90% are now being achieved consistently. This article provides an overview of these revolutionary techniques for oral cavity, mandibular, and hypopharyngeal reconstructions. Patients are selected for microvascular free tissue transfer because of the large size of their defect, its location (eg, anterior mandibular loss), or complexity (circumferential defects of the hypopharynx). Others may be good candidates for this surgery because of previous radiotherapy or failed reconstructive surgery. Donor sites range from the radial forearm to the jejunum.

Follow-Up Studies↗
PubMed1991

The effect of postoperative radiation therapy on pharyngoesophageal reconstruction with free jejunal interposition.

Free tissue transfer of a jejunal segment was undertaken for laryngopharyngoesophageal reconstruction in 20 patients who received postoperative irradiation therapy. Treatment consisted of 1.8- to 2-Gy-fractions, the average total dose was 55.57 Gy (range, 40 to 66 Gy). Anastomotic strictures (six) were encountered early in the series and associated with stapled anastomoses. Hand-sewing the jejunoesophagostomy eliminated the problem. Enteric cutaneous fistula, bowel necrosis, and hemorrhagic enteritis were not observed. We conclude that the application of postoperative irradiation therapy to patients requiring jejunal interposition grafts is feasible.

Adolescent↗
PubMed1991

Double lumen free jejunal transfer for reconstruction of the entire floor of mouth, pharynx and cervical oesophagus.

In those patients requiring proximal extension of a laryngopharyngectomy to include resection of the base of the tongue, there is a considerable mismatch between the circumference of the superior pharyngeal defect and a conventional jejunal conduit. An inverted J-shaped jejunal funnel can be prefabricated to enlarge the proximal stoma of a free jejunal transfer to overcome this size discrepancy and so prevent the high incidence of postoperative fistulae at the proximal anastomosis. In the most extreme case it will allow reconstruction of the entire floor of the mouth, pharynx and cervical oesophagus.

Adult↗
PubMed1991

Acute and chronic ischemia of the hand: pathophysiology, treatment, and prognosis.

Fifty consecutive patients with acute and chronic ischemia of the hand were investigated by Allen testing, Doppler ultrasound, digital plethysmography, and angiography over a 4-year period. The pathophysiologic mechanism responsible for the ischemia was determined to be emboli in 6%, vasospasm in 10%, thrombosis or "sludging" in 28%, occlusive disease in 26%, and occlusive disease associated with either vasospasm or external compression in 30%. Ten patients required emergency medical treatment with intraarterial streptokinase, intravenous heparin, or dextran 40 and continuous stellate ganglion blocks, and three patients required emergency microsurgical revascularization because of radial artery thrombosis. Patients with chronic ischemia of the hand were maintained on nifedipine, 30 to 60 mg daily, and pentoxifylline, 1200 mg daily. Seven patients underwent digital sympathectomy and 14 patients underwent microsurgical revascularization as prophylactic procedures for chronic digital ischemia. Amputations were required in 18 patients because of end-stage gangrene. Long-term follow-up revealed a 20% incidence of recurrent digital ulcerations. There have been six deaths during follow-up, five of them due to myocardial infarction; this reflects the underlying systemic arteriopathy in many of these patients.

Acute Disease↗
PubMed1991

Pacinian corpuscle hyperplasia in the hand.

Proliferation of pacinian corpuscles adjacent to the digital nerves in the hand is very rare. Patients are usually seen initially with a history of previous trauma and severe localized pain. The symptoms, signs, and surgical treatment of previously reported cases are reviewed and histological criteria from this case are proposed to define this condition. In addition to a neuroma or glomus tumor, pacinian corpuscle hyperplasia should be considered in the differential diagnosis of digital or palmar pain.

Diagnosis, Differential↗
PubMed1991

Glomerular epithelial cell endocytosis of immune deposits in human lupus nephritis.

Sixteen human renal biopsies taken from patients suffering from systemic lupus erythematosus nephritis were examined using an immunohistochemical method which allows the localisation of IgG at both light and electron-microscopical levels. The tissue was embedded in the hydrophilic resin lowicryl K4M and sections were stained using gold-labelled antibodies. On routine light microscopical examination the biopsies were diagnosed as: 1 case of WHO type II, 3 type III, 9 type IV, 2 type V, and 1 type III/V. Using light microscopy, IgG was localised in the glomerulus using the IGSS staining method. In some cases staining was seen within the glomerular epithelial cell cytoplasm. At the ultrastructural level the presence of IgG was demonstrated within vesicles in the cytoplasm of the epithelial cells in 0/1 type II, 2/3 type III, 8/9 type IV, 1/2 type V, and 1/1 type III/V cases: in some vesicles deposits of immune material were electron-dense but in others immune material was electron-lucent. Our results suggest that the human glomerular epithelial cell can endocytose IgG and that this may be part of a clearance mechanism acting within the glomerulus.

Endocytosis↗
PubMed1991

Treatment of chronic infected hip arthroplasty wounds by radical debridement and obliteration with pedicled and free muscle flaps.

Nine patients with extensive wounds of the hip joint due to chronic infection following total hip arthroplasty or internal fixation of fractures of the femoral head and neck have been treated by serial radical debridements to remove infected bone, contaminated remnants of bone cement, and the surrounding fibrotic soft tissues. The resultant deep cavity extending down to the acetabulum has then been obliterated with either pedicled muscle flaps or free muscle flaps. Subcutaneous or transpelvic transposition of rectus abdominis muscle flaps is preferred for smaller defects, but only the free latissimus dorsi muscle flap provides sufficient volume of tissue to obliterate the more extensive hip defects. Systemic antibiotics have been continued only for a short-term course of 14 days postoperatively. There has been no recurrence of infection, with follow-up ranging between 6 months and 3 1/4 years. One patient has undergone reimplantation of a second custom hip prosthesis into the vascularized bed of a free latissimus dorsi muscle flap.

Adult↗
PubMed1991

Microsurgical free-tissue transfer in the elderly patient.

During the 5-year period from July of 1984 to July of 1989, we performed 94 free-tissue transfers in 92 patients over the age of 50 whom we arbitrarily defined as "elderly." There were 32 patients in the age range between 50 and 59 years, 40 patients aged between 60 and 69 years, and 20 patients aged between 70 and 79 years. Seventy-one flaps were utilized for head and neck reconstruction, and 23 flaps were used in reconstruction of the trunk and extremities. There was 1 total flap loss, for a flap viability rate of 99 percent (93 of 94). Postoperative complications were classified into surgical (technical) and medical categories. There were 14 major surgical complications (15 percent) and 13 significant postoperative medical problems (14 percent). The majority of these complications occurred in head and neck cancer patients in the age group between 60 and 69 years, who had significant underlying medical problems and were preoperatively classified as ASA 3. There were 5 postoperative deaths, for a mortality rate of 5.4 percent (5 of 92 patients).

Age Factors↗
PubMed1990

Reduced duck hepatitis B virus viraemia in ducklings coinfected with the immunodepressive reticuloendotheliosis virus.

Coinfection of avian hosts by duck hepatitis B virus (DHBV) and reticuloendotheliosis virus (REV) was studied to assess the effect of immunodepression by REV on the replication of DHBV. One-day-old ducklings, domestic chickens, and turkey poults were inoculated either with DHBV or DHBV and REV and were bled and weighed at regular intervals. DHBV infection as manifested by viraemia and DHBV DNA in liver was established only in ducklings. All chickens and turkeys were negative for DHBV DNA in serum and liver. However, ducklings coinfected with REV showed a delayed onset and reduced level of viraemia compared to ducklings infected only with DHBV. The narrow host range of DHBV was confirmed even in immunodepressed species. It is suggested that the reduction in DHBV viraemia in ducklings was due to factors not involving the specific immune system.

Animals↗
PubMed1990

Jejunal interposition for repair of stricture or fistula after laryngectomy.

Complications following total laryngectomy may include pharyngocutaneous fistula or pharyngeal stricture. Traditional techniques of repair of fistula and stricture with local or regional flaps lead to a high rate of failure. In this study, we report 18 patients treated by secondary jejunal interposition (JI) to rehabilitate swallowing following recalcitrant postlaryngectomy stricture or fistula. All patients had undergone total laryngectomy with or without partial pharyngectomy for treatment of squamous cell carcinoma of the larynx (8) or hypopharynx (10). Four were stage II; 5, stage III; and 9, stage IV. Thirteen patients (72%) regained swallowing function. Complications of secondary JI included perioperative death (2), flap loss (1), and persistent fistulas (3). Jejunal interposition may be the best modality in the rehabilitation of swallowing in patients with persistent fistula or stricture that fails to respond to traditional management.

Aged↗
PubMed1989

Natural infection of duck embryos with duck hepatitis B virus: time and tissue sequence of infection.

There have been no studies addressing the detailed sequence of embryonic infection with duck hepatitis B virus (DHBV). Therefore, duck embryos from flocks infected with DHBV were examined to study the sequence of infection by DHBV in various embryonic tissues. Embryos from flocks infected with DHBV were harvested in duplicates from 7 to 25 days of incubation. Whole embryos (to 12 days) or dissected embryonic tissues were fixed, paraffin embedded, and stained for DHBV surface antigen (DHBsAg) using a peroxidase-antiperoxidase technique. Isolated hepatic cells were infected in 7-day-old embryos, and these increased in number until 11 days, when most cells were positive for DHBsAg. Endocrine pancreatic cells were positive from day 10, but only an occasional exocrine pancreatic cell was infected after day 20. Renal tubule cells were positive for DHBV by day 11, increasing in number until about day 18, after which a decline in numbers of infected cells occurred. Renal glomeruli became positive for DHBsAg from day 24. When present in the developing embryo, thymus, bursa of Fabricius, spleen, bone marrow, lung, and duodenum remained negative for DHBsAg. It was concluded that the timing of infection of specific tissues was not necessarily related to cellular maturity but may reflect a need for specific metabolic functions that permit viral replication.

Animals↗
PubMed1989

Experimental and clinical monitoring of free jejunal transfers using an implantable ultrasonic Doppler probe.

Postoperative assessment of the continued viability of a "buried" free jejunal transfer remains a difficult problem. The reliability of a 20 MHz pulsed ultrasonic Doppler probe to detect arterial or venous occlusion has been investigated experimentally in isolated vascularised jejunal segments in dogs. Clinically, the probe has been used intraoperatively to confirm normal flow in both the mesenteric artery and mesenteric vein of free jejunal transfers. Continuous recording of the acoustic signal from the probe during closure of the incisions has allowed immediate detection of any adverse effect due to pedicle kinking or excessive skin tension. Sixteen patients undergoing free jejunal transfer have been monitored continuously using the implantable 20 MHz pulsed ultrasonic Doppler probe positioned on the inflow mesenteric artery.

Animals↗
PubMed1989

Hypopharyngeal reconstruction: a comparison of two alternatives.

Gastric pull-up or free jejunal interposition was used for reconstruction after total laryngopharyngectomy in 31 patients. Complications and functional outcomes of the two methods are compared. Primary swallowing was achieved in 86% of patients after gastric pull-up and in 82% of patients after jejunal interposition. Patients who underwent jejunal interposition were able to swallow sooner and had a shorter hospital stay than patients who underwent gastric pull-up. Esophageal tumor recurrence after jejunal interposition was not observed. Hepatic failure occurred in two gastric pull-up patients, leading to perioperative death in one. Flap necrosis occurred in two jejunal interposition patients and one gastric pull-up patient. Two additional fistulas occurred in jejunal interposition patients as a result of microvascular complications. Stricture developed in four jejunal interposition patients, requiring revision surgery in two. Minor complications were more common in the gastric pull-up group. Long-term speech and swallowing function are compared. Our current choice of jejunal interposition or gastric pull-up for reconstruction after total laryngopharyngectomy primarily depends on the location of the tumor.

Aged↗
PubMed1988

Immediate microvascular reconstruction of combined palatal and midfacial defects using soft tissue only.

Maxillary and midface defects with or without orbital involvement are disfiguring and disabling problems especially in the elderly cancer patient. Often, palatal prostheses are required to enable speech and swallowing. Elderly patients or those with compromised vision often find these appliances cumbersome and difficult to manage. To help obviate these problems a one-stage method of immediate palatal reconstruction was needed to obturate the palate and restore facial contour. Over the past 18 months six patients have undergone immediate reconstruction of complex, composite defects of the maxillary and midface structures after tumor extirpation, three of which extended into the orbit. The latissimus dorsi musculocutaneous flap was utilized because of its bulk, reliable anatomy, ample pedicle length and diameter, and minimal donor site morbidity. No flap loss, suture line dehiscence, or infection occurred. All patients were capable of deglutition and intelligible speech. This technique is a one-stage reconstruction of the palate and accompanying defects of the midface and maxilla that obviates the need for cumbersome palatal appliances.

Carcinoma, Squamous Cell↗
PubMed1988

Postoperative monitoring of microsurgical free tissue transfers for head and neck reconstruction.

Approximately 10% of free tissue transfers fail because of thrombosis of the arterial or venous anastomoses. Postoperative monitoring to allow early detection of impaired flap perfusion is crucial, especially in head and neck reconstruction, in which failure of a free flap may be associated with significant morbidity. Furthermore, the increasing use of "buried" free tissue transfers in the head and neck precludes direct clinical observation. The various techniques that have been advocated for clinical monitoring of free tissue transfers are reviewed, and their potential applications in head and neck reconstruction are discussed with specific emphasis on the use of low-frequency continuous-wave Doppler surface monitoring and implantable high-frequency pulsed ultrasonic Doppler monitoring.

Animals↗