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Biomedical subjects

J N Keeman

Publications and source records attributed to J N Keeman.

At least 37 records · Page 2Linked to original sources
PubMed1994

The evolution of renal angiomyolipomas in patients with tuberous sclerosis.

In 1986, 23 patients with renal angiomyolipomas as part of tuberous sclerosis were assessed by ultrasonography. In 1991, 20 patients in this group were reexamined with special attention paid to the renal pathological condition. Ultrasonography was performed by the same radiologist who performed the examination in 1986. Of 20 patients 7 had severe hemorrhage necessitating hospital admission (5 had a renal lesion larger than 3.5 cm. in diameter). In 2 patients the exact diameter of the renal angiomyolipomas could not be determined and they underwent nephrectomy. Three patients underwent successful selective embolization of the bleeding angiomyolipoma. One patient died. The hemorrhage resolved spontaneously in 1 patient and treatment was not feasible. In 4 patients the lesions increased in size between 1986 and 1991. Based on these results there is a relationship between the size of the angiomyolipomas and the risk of bleeding. Renal angiomyolipomas larger than 3.5 cm. in diameter have a substantial risk for severe hemorrhage. Some angiomyolipomas show progression. Periodic followup is mandatory every 6 months. For angiomyolipomas larger than 3.5 cm. in diameter an aggressive approach is advised. Selective embolization is the initial method of choice.

Adult↗
PubMed1994

Colour flow imaging of the normal short saphenous vein.

Colour flow imaging was used to assess the functional anatomy of the short saphenous vein (SSV) system in 104 limbs of 52 healthy volunteers. Previous studies have shown that the majority of pathological SSVs join the popliteal vein (PV) at the level of the knee. This was not the case in nearly half of the healthy limbs in this study. In these limbs the SSV retained its early embryonic function of providing venous return from the superficial system of the lower leg into veins of the upper leg and buttock. Is this a developmental safety valve?

Adult↗
PubMed1991

[Injuries due to fireworks at the turn of the year 1990/'91].

During the festivities at the turn of the year 1990, 58 patients with firework-related injuries were seen. A 200% increase in relation to previous years was observed. Minor blast injuries of the hand were the most frequent. Many children of Turkish and Moroccan nationality were involved. It was surmised that illegal and unsafe fireworks in combination with careless behaviour were causative factors. Prevention should be achieved through amending the law on use and distribution of fireworks and through intensifying and fine-tuning the annual information campaigns.

Adolescent↗
PubMed1991

[Complete rupture of the tendon of the biceps muscle of the thigh].

Complete rupture of the tendon of the M. biceps femoris proximal to its insertion is a rare occurrence. Relatively few patients have been recorded. We describe a patient with a complete rupture sustained as a result of a water skiing accident, viz. a fall over the stern wave. The case history was in accordance with a theory about the cause of this lesion--sudden overstretching of the hamstrings. The diagnosis was made by physical examination in the acute phase. With the patient in supine, 90 degrees flexed knees position and with isometric contraction of his hamstrings it is easy to mark and palpate a defect of the tendon just proximal to the caput fibulae. After operative reconstruction, a plaster cylinder was used for five weeks' postoperative immobilization. Five weeks after surgery, physical therapy was started, first to regain knee motion, and later to regain strength. Twelve weeks after surgery, the patient resumed working and recreational sports.

Athletic Injuries↗
PubMed1991

Preoperative localisation of the saphenopopliteal junction with duplex scanning.

The anatomy of the saphenopopliteal junction shows considerable variation, and clinical localisation of this junction is inaccurate. Duplex scanning in preoperative mapping of the saphenous vein system in bypass surgery has been shown to be highly effective. In 62 patients with clinical evidence of insufficiency of the saphenopopliteal junction, preoperative localisation with duplex scanning was performed in 66 extremities. In 62 extremities duplex localisation matched the operative findings and in four extremities a difference of 2 cm or more was found. There was 1 false negative surgical exploration. In 93% of the cases exact localisation of the junction enabled us to perform flush ligation of a small saphenous vein through minimal exposure. Preoperative duplex scanning of the saphenopopliteal junction is highly accurate.

Female↗
PubMed1991

Aortocaval fistulas.

The only effective treatment of an aortocaval fistula is the surgical closure of the fistula opening with insertion of an aortic prosthesis to restore the arterial continuity. The diagnosis of this distinct but infrequent clinical entity is often missed because of lack of suspicion. Proper preoperative evaluation facilitates the choice of surgical approach and reduces the morbidity. Three patients are presented with an aortocaval fistula: two with spontaneous rupture of an atherosclerotic abdominal aneurysm into the inferior vena cava and one with a traumatic fistula following intervertebral disk surgery 33 years before. All three patients suffered from pain in the abdomen and back, a palpable pulsatile abdominal mass and an audible continuous harsh bruit. Cardiac failure was present in two of them. Successful surgical closure could be accomplished in two patients although the perioperative course was complicated by ventricular arrhythmia, profuse blood loss and an inferior vena cava syndrome. One patient with a spontaneous aortocaval fistula passed away due to intraoperative exsanguination.

Aged↗
PubMed1990

Transscaphoid perilunate fracture dislocation and pseudarthrosis of the scaphoid.

The results of conservative treatment of a perilunate fracture dislocation were retrospectively studied. In six patients, the treatment consisted of closed reduction and immobilization in a below the elbow cast for 12 to 16 weeks. Five patients had a compromised healing of the scaphoid fracture. The frail vascularization of the scaphoid, extensive ligamentous injury and possible mid-carpal instability in case of perilunate fracture dislocation as well as a non-anatomical reduction of a scaphoid fracture are causative factors in ensuing scaphoid pseudarthrosis. If anatomical reduction of a perilunate fracture dislocation cannot be obtained, open reduction and internal fixation should be considered. This will offer the scaphoid the best chance at fracture healing and will restore the stabilizing function on the mid carpus.

Adult↗
PubMed1990

Mesenteric venous thrombosis caused by deficiency of physiologic anti-coagulants: report of a case.

Mesenteric venous thrombosis is a clinical entity, which is rarely recognized on admission. The patients are admitted with vague abdominal complaints and, eventually, abdominal sepsis might occur requiring laparotomy. Nowadays, underlying hypercoagulable states such as antithrombin-III, protein-C and protein-S deficiencies are recognized more frequently as a distinct cause of mesenteric venous thrombosis. In this paper, a case of mesenteric venous thrombosis due to protein-C deficiency is presented. The patients generally have a history of thromboembolism of the deep veins of the legs at young age. The combination of vague abdominal complaints and a history of thrombosis of the deep veins of the legs should arouse the suspicion of mesenteric venous thrombosis. In these cases, contrast-enhanced computerized tomography is a non-invasive diagnostic means which may provide the diagnosis. If infarction of the gut is present, resection is mandatory and a second-look operation should be performed. After surgery, heparinization is essential. This must be followed by administration of oral anticoagulants for an indefinite period in case of an underlying antithrombin III, protein-C or protein-S deficiency.

Adult↗
PubMed1989

[HIV occupational risk of surgical specialists and operating room personnel in the Saint Lucas Hospital in Amsterdam].

All instrument and needle accidents, and mucosal exposure to blood involving surgical specialists and operating room personnel were recorded for a seven-month period in a middle-sized Amsterdam hospital, the St. Lucas. Fifty-four accidents were reported, of which 42 were percutaneous wounds and 12, blood splatters in the eyes. The frequency of percutaneous wounds per operation per person ranged from 0 to 0.013. In the same period 3098 patients who had to be operated on were asked to participate in an anonymous study for HIV antibody. One hundred and twenty patients refused participation (3.9%). Of the 2978 participating patients seven were seropositive for anti-HIV (0.23%). The observed percutaneous accident frequency and HIV prevalence were used in combination with reports from the literature on the risk of infection after a single exposure to HIV infected material, to calculate the HIV professional risk for operating room personnel in this hospital. For general surgeons the risk of infection (based on 500 operations per year) was calculated as 0.0012 for an occupational lifespan of 30 years. For the other specialists and functions the risk was the same or less. Considering the low risk our conclusion is that screening of preoperative patients is not necessary in this hospital. The observance of general protective measures provides sufficient protection for the professional group examined.

Accidents↗
PubMed1989

Volvulus of the stomach after traumatic hernia diaphragmatica.

A patient with gastric volvulus after traumatic diaphragmatic rupture is reported. The trias of Borchardt (pain in epigastrio with gastric distension, hiccups with the inability to vomit, inability to secure the passage of a nasogastric tube) must raise the suspicion on acute gastric volvulus, especially if these abdominal complaints are associated with blunt abdominal trauma in the past. In these cases, lateral X-ray examinations of the chest and swallowing studies establish the diagnosis.

Adolescent↗