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Biomedical subjects

M Brock

Publications and source records attributed to M Brock.

At least 109 records · Page 6Linked to original sources
PubMed1993

Percutaneous endoscopic lumbar discectomy (PELD).

Percutaneous endoscopic lumbar discectomy (PELD) is a new technique for the decompression of the lumbar disc space and removal of nucleus pulposus via a posterolateral approach. The technique was introduced in Germany by the authors in April 1987. The method is indicated in patients with nonsequestrated lumbar disc herniation with an intact dorsal longitudinal ligament. In local anesthesia, a working cannula (OD 5 mm) is placed at the dorsal lateral border of the disc. The disc space is opened with anulus trephines and the nucleus pulposus is removed with rigid and flexible forceps as well as with automated shaver systems under intermittent endoscopic control (discoscopy). The procedure is performed in local anesthesia. The results of the first thirty patients with a follow-up time between 6 months and 17 months could be graded as excellent in 13 cases, as good in 9 cases, as fair in 6 cases, and as bad in 2 cases. The relief of symptoms as judged by the patients was between 70-100 percent in the majority of the cases. Three patients had to be reoperated at the same level and site, because of either persistent or recurrent sciatica. The performance in local anesthesia, the atraumatic extraspinal approach, the reduced time of hospitalization and postoperative morbidity as well as the reduced time of work incapability are the main advantages of this new method.

Adult↗
PubMed1993

Nucleus pulposus regeneration after chemonucleolysis with chymopapain?

Chemonucleolysis was unsuccessful in 100 out of 519 patients with herniated lumbar discs treated within a period of 3 years. These patients were subsequently submitted to open surgery. Disc material from 88 of the 100 patients was examined by light microscopy (hematoxylin and eosin, van Gieson's, Nissl's and periodic acid-Schiff staining) to verify the effect of enzymatic activity compared to the histologic findings in a similar control group. In 84 of the 88 cases, signs of enzymatic activity were revealed by eosinophilia of the ground substance, altered Nissl staining and positive periodic acid-Schiff reaction within the chondrocyte halos. These alterations indicate that the enzyme was active and confirm the results of previous studies with smaller numbers of cases. Histologic alterations were quantified according to the intensity and extent of staining. The signs of enzymatic activity were significantly (P < 0.01) stronger after short time intervals between chemonucleolysis and surgery than after long intervals. These findings may be interpreted as indicating a regenerative potential of the nucleus pulposus.

Adult↗
PubMed1993

Percutaneous endoscopic discectomy: surgical technique and preliminary results compared to microsurgical discectomy.

Percutaneous endoscopic discectomy is a new technique for removing "contained" lumbar disc herniations (those in which the outer border of the anulus fibrosus is intact) and small "noncontained" lumbar disc herniations (those at the level of the disc space and occupying less than one-third of the sagittal diameter of the spinal canal) through a posterolateral approach with the aid of specially developed instruments. The technique combines rigid straight, angled, and flexible forceps with automated high-power suction shaver and cutter systems. Access can thus be gained to the dorsal parts of the intervertebral space where the disc herniation is located. Percutaneous endoscopic discectomy is monitored using an endoscope angled to 70 degrees coupled with a television and video unit and is performed with the patient under local anesthesia and an anesthesiologist available if needed. Its indication is restricted to discogenic root compression with a minor neurological deficit. Two groups of patients with contained or small noncontained disc herniations were treated by either percutaneous endoscopic discectomy (20 cases) or microdiscectomy (20 cases). Both groups were investigated in a prospective randomized study in order to compare the efficacy of the two methods. The disc herniations were located at L2-3 (one patient), L3-4 (two patients), or L4-5 (37 patients). There were no significant differences between the two groups concerning age and sex distribution, preoperative evolution of complaints, prior conservative therapy, patient's occupation, preoperative disability, and clinical symptomatology. Two years after percutaneous endoscopic discectomy, sciatica had disappeared in 80% (16 of 20 patients), low-back pain in 47% (nine of 19 patients), sensory deficits in 92.3% (12 of 13 patients), and motor deficits in the one patient affected. Two years after microdiscectomy, sciatica had disappeared in 65% (13 of 20 patients), low-back pain in 25% (five of 20 patients), sensory deficits in 68.8% (11 of 16 patients), and motor deficits in all patients so affected. Only 72.2% of the patients in the microdiscectomy group had returned to their previous occupation versus 95% in the percutaneous endoscopic discectomy group. Percutaneous endoscopic discectomy appears to offer an alternative to microdiscectomy for patients with "contained" and small subligamentous lumbar disc herniations.

Adolescent↗
PubMed1993

[Postoperative air embolism caused by pneumatocephalus following occlusion of the posterior fossa. A rare complication indicative of a bridging vein disruption].

Many neurosurgeons prefer the sitting position for patients undergoing surgery in the posterior fossa because of the easier access and better conditions for haemostasis. Pneumatocephalus is a possible consequence of surgery in the posterior fossa with the patient in the sitting position. When this occurs air may enter the subarachnoid space, the cisternae, the ventricular system or the subdural space; it becomes more likely when any of the following is/are present: loss of CSF, a large cavity resulting from surgery, external or internal drainage of CSF, osmotic diuresis, and hyperventilation. Distances of 1-2 cm between cranium and brain may be found. The rupture of bridging veins may cause a subsequent subdural haematoma. Air embolism due to pneumatocephalus via the same vein after closure of the cranium is in this paper for the first time. Case report. A 37-year-old man with known Hippel-Lindau disease presented for posterior fossa surgery for treatment of a haemangioblastoma of the right cerebellar hemisphere. Surgery was done with the patient in a sitting position. Apart from one short episode of air embolism without haemodynamic changes no intraoperative complications occurred. After closure of the cranium and galea an unexpected and inexplicable air embolism of 10 min duration occurred again. TEE demonstrated the air looking like a string of beads in the right atrium. As complete skin had already been closure no explanation for the air embolism could be found. The patient was positioned supine, and air was no longer detectable in the right heart after 1 min. Approximately 1 h later both pupils were dilated and unreactive to light.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

The recurrent carpal tunnel syndrome.

Sixteen out of 720 patients with carpal tunnel syndrome who had undergone surgery since 1979 were reoperated for a "recurrence" (2.2%). Twelve of these patients had been originally operated on in our department. Thus, our own recurrence rate is 1.7%. Three patients deteriorated following surgery, 6 had an unsatisfactory improvement, and in 7 the symptoms recurred after initial improvement. Eight of the reoperated patients had a predisposing disease (terminal renal insufficiency, insulin-dependent diabetes mellitus, acromegaly). In 10 of the 16 cases the initial operation had been carried out by surgeons in the first three years of training. Reoperation revealed incomplete splitting of the transverse carpal ligament in 10 cases, compression of the median nerve by the scar in 4, injury of the muscular branch in 1, and an anatomical variant as cause of incomplete decompression in 1 patient. "Recurrences" after carpal tunnel surgery are predominantly due to inadequacies of the first procedure. A remarkable number of patients (50%) has predisposing diseases. Interfascicular or epineural neurolysis and complete exposure and neurolysis of the median nerve and its branches is necessary only in cases of recurrence. Their omission at the first surgery does not result in an increased recurrence rate. Our observations indicate that the number of operations for recurrent carpal tunnel syndrome can probably be reduced when the first operation is performed with care and experience. Patients with carpal tunnel syndrome secondary to a systemic disease are particularly at risk.

Acromegaly↗
PubMed1992

Percutaneous endoscopic laser discectomy (PELD). A new surgical technique for non-sequestrated lumbar discs.

Basic features and techniques of percutaneous endoscopic laser discectomy are described and the results in 6 patients reported. Indications are: discogenic radicular symptoms, caused by disc protrusions, which do not respond to conservative treatment. Contra-indications are: major neurological deficit, segmental instability and spondylolisthesis, extruded disc prolapse, narrow spinal canal or lateral recess.

Adult↗
PubMed1992

The form and structure of the extruded disc.

There are no detailed data in literature concerning the histologic nature of the sequestered (extruded) lumbar disc, and on the frequency with which an extruded fragment, a prolapse or a protrusion are found at surgery. A prospective analysis of 100 consecutive cases of sequestered lumbar disc herniation submitted to surgical treatment revealed this group to represent 28.6% of all cases operated on for lumbar disc herniation. Patients (both male and female) with sequestered lumbar discs are significantly older than those with prolapsed (P < 0.01) and protruded (P < 0.001) discs. Single extruded fragments (n = 68) were twice as frequent as multiple ones (n = 32). The general belief that a 'sequestered (extruded) disc' is almost invariably composed of nucleus pulposus is not substantiated by this study: In 54 cases the extruded fragment consisted predominantly of nucleus material, whereas in 44 cases it consisted mainly of end-plate material. Multiple as well as recurrent sequestered fragments almost always consist of end-plate material. These findings may reflect the result of metabolic alterations in the course of disc degeneration.

Adult↗
PubMed1992

A plan to suppress or prevent the immune rejection of allografted organs.

Progress in the resolution of allograft rejection and associated complications has been hampered by the nonselective nature of current immunosuppressive therapy. In the following protocol, we proposed instead of broadly suppressing immunoreactivity to remove selectively from the bloodstream supplying the transplanted organ only those T lymphocytes and/or antibodies capable of reacting with and destroying the allograft. This goal is to be accomplished by offering them (T cells and/or antibodies) a decoy of antigenically identical tissue. The proposed procedure has the added advantage that it may activate suppressor T cells specific for the allogenic tissue, thereby further promoting acceptance of the graft while providing the host immune system the opportunity to recognize the allograft as autochthonous.

Animals↗
PubMed1991

The results of "lumbar disc surgery" following unsuccessful chemonucleolysis.

A group of 100 patients submitted to microsurgical treatment for herniated lumbar disc following unsuccessful chemonucleolysis with chymopapain were retrospectively compared to a statistically comparable group of patients primarily submitted to microsurgery. This comparison demonstrated that previous unsuccessful chemonucleolysis has no influence on either the short-term or the long-term results of subsequent microsurgery.

Adult↗
PubMed1990

[Surgical treatment of iatrogenic lesions of the accessory nerve following lymph node excision].

Excision of lymph nodes on the lateral margin of the sterno-cleido-mastoid muscle may result in damage to the accessory nerve. Most commonly the branch to the trapezius is involved. The treatment in five cases of iatrogenic lesions is described. Contrary to the widespread assumption that these lesions are irreversible, there was significant improvement in all cases.

Accessory Nerve Injuries↗
PubMed1990

[Acute progressive paralysis caused by intraneural ganglion--a neurosurgical emergency].

Intraneural ganglia, particularly of the peroneal and ulnar nerves may produce rapidly progressive paresis after minor trauma, for instance, following a sport injury. The chance of recovery of nerve function depends on the timing of surgical treatment. A patient with a ganglion of the peroneal nerve is reported in order to stress the relevance of intraneural ganglia, the danger of missing the lesion and the importance of early treatment. It is stressed that in the presence of rapidly progressing paralysis and the clinical suspicion of an intraneural ganglion, early decompression offers the best prognosis for recovery.

Adult↗
PubMed1990

Pituitary metastases.

Over the past 12 years we encountered three histologically confirmed pituitary metastases. Primary cancer had been diagnosed and treated previously in only one patient. In the remaining two a transsphenoidal operation provided the initial diagnosis of metastasis, and the primary lesion was subsequently detected at autopsy in one. In two of the three patients symptoms and signs of pituitary dysfunction were the first manifestations of the malignant disease. The main symptoms and signs were impairment of visual acuity, visual field defect, headache, adenohypophyseal insufficency and diabetes insipidus. A sellar mass was demonstrated by CT or MRI in all patients. The tumours were all completely extirpated by subfrontal route in one case and transsphenoidally in the remaining two patients. Following surgery the presenting symptoms improved satisfactorily in all patients.

Adenocarcinoma↗
PubMed1990

[Intramedullary neurinoma. Case report].

The case of a 36-year-old patient with an intramedullary neurinoma of the thoracic spine without Recklinghausen's disease is presented. The intramedullary neurinoma is a very rare condition. Only 33 cases have been reported in the literature. To our knowledge, the case presented here is the first in German literature. The treatment of choice is tumor removal. The case described here was diagnosed by magnetic resonance imaging (MRI). Histologically, the tumor showed all features characteristic of a neurinoma. Postoperatively, the patient is nearly without complaints.

Adult↗
PubMed1989

Lumbar disk compliance and degeneration.

Comparison between 242 intradiscal pressure/volume recordings and corresponding diskograms (performed at the same occasion) has shown a significant (p less than 0.01) correlation between disk compliance and the degree of diskographic degeneration. Intradiscal pressure/volume testing is a simple, reliable, and risk-free procedure that should precede every diskogram and be incorporated into the preoperative diagnostic routine of patients undergoing chemonucleolysis or percutaneous diskectomy.

Adolescent↗
PubMed1989

[Initial experiences with implanted drug pumps for continuous intrathecal calcitonin therapy in therapy-resistant pain].

The hormone calcitonin has proved itself for some years in the treatment of chronic pain syndromes. In addition to its known influence on calcium exchange it gives vise to an analgesic effect within the central nervous system and this follows systemic administration or after bolus intrathecal injection. Two patients with chronic non malignant pain are presented in whom continuous delivery pumps have been used for intrathecal Lachs-Calcitonin (Karil, Fa. Sandoz).

Brachial Plexus Neuritis↗