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PubMed2006

Nerve root decompression without fusion in spondylolytic spondylolisthesis: long-term results of Gill's procedure.

Nerve root decompression with instrumented fusion is currently most commonly performed in the treatment of patients with spondylolytic spondylolisthesis. The relationship between successful fusion and clinical outcome remains controversial, thereby questioning the necessity of fusion. Nerve root decompression without fusion, i.e. Gill's procedure, might be a less invasive surgical alternative with comparable clinical outcome. The objective of this study is to compare the long-term results of Gills's procedure with data from literature on decompression with fusion, and, moreover, to determine if a future randomised trial is legitimate. We retrospectively reviewed the long-term results of Gill's procedure in patients with grade I or II spondylolytic spondylolisthesis. All patients suffered from leg pain with or without low back pain. No patient had low back pain alone. In 17 patients a bilateral and in 25 patients a unilateral Gill's procedures were performed. The patients were evaluated at three follow-up moments. On moment 1, 38 patients were clinically examined on their last out-patient control (mean follow-up 11 months). On moment 2, 34 patients were interviewed by telephone (mean follow-up 4.4 years). The final long-term follow-up moment 3 (mean follow-up 10.5 years) included a mailed patient-satisfaction questionnaire of 31 patients (response rate 74%). No surgical complication occurred. Ten of the 42 patients were reoperated because of persistent or recurrent radicular pain (mean time interval 2.9 years). Kaplan-Meier analysis showed a disease-free survival rate of 79% at 5 years and 72% at 10 years after the index operation. On the three follow-up moments, the improvement of leg pain was 92, 97 and 88%, respectively. The final long-term follow-up showed 71% good result in terms of patient satisfaction. The Gill's procedure is a less invasive surgical technique in the treatment of patients with leg pain due to low-grade spondylolytic spondylolisthesis. This technique can be considered as an alternative to instrumented fusion in selected cases. Preoperative instability, discectomy at the affected level and neuroforaminal nerve root compression seem to be negative influencing factors, increasing the risk for secondary instrumented surgery. The results of this study justify a randomised trial.

Adult↗
PubMed2002

Cranio-cervical decompression for Chiari type I-malformation, adding extreme lateral foramen magnum opening and expansile duroplasty with arachnoid preservation. Technique and long-term functional results in 44 consecutive adult cases -- comparison with literature data.

BACKGROUND: Posterior cranio-cervical decompression by opening at least foramen magnum and C1-lamina usually with corresponding dural and arachnoid opening, is the procedure most currently used for treating Chiari I malformation (alone or in association with syringomyelia). To optimize decompressive effects together with reducing risks, a procedure was developed which consists of a sub-occipital craniectomy and a C1 (or C1/C2) laminectomy, plus an extreme lateral Foramen Magnum opening, a "Y" shaped dural incision with preservation of the arachnoid membrane, and an expansile duroplasty employing autogenous periosteum. The purpose of the article is:1. to report the long-term functional results in a consecutive series of 44 adult patients affected by symptomatic Chiari Malformation type I (CM) using the procedure described.2. and to compare this technical modality with the other modalities reported in the literature. METHOD: This series includes 44 patients harboring CM type I and operated on between 1990 and 2000. 15 patients had CM with syringomyelia (34%) and 29 CM alone (66%). Functional status was evaluated by using the Karnofsky disability scale. Before surgery 37 patients (84.1%) were independent (of whom 13 had syringomyelia) and 7 patients (15.9%) were dependent - i.e., they required assistance - (of whom 2 had syringomyelia). Outcomes were analized with follow-up ranging from 1 to 10 years (4 years on average). FINDINGS: There was no operative mortality, and surgery did not provoke any neurological aggravation. After surgery all the patients were independent. For the patients with CM only, the averaged Karnofsky score was 90 at latest follow up, versus 76 before surgery. For the patients with syringomyelia, the averaged latest Karnofsky score was 89 after surgery, versus 74 before. INTERPRETATION: The presented technique was compared with the other surgical modalities reported in the literature. This comparative study shows that cranio-cervical decompression with extreme lateral resection of the posterior rim of Foramen Magnum out to the level of the occipital condyles on either side, associated with an enlargement duroplasty with preservation of the arachnoid membrane, achieved the best results with minimal complications and side-effects.

Activities of Daily Living↗
PubMed2004

Quality of life after decompressive craniectomy in patients suffering from supratentorial brain ischemia.

BACKGROUND: Decompressive craniectomy in patients suffering from severe ischemic stroke in the middle cerebral artery territory (MCA) decreases mortality to near 30%. Additionally functional outcome in patients after early craniectomy seems to be better than in patients without surgery. The aim of this study was to investigate the quality of life of patients who were treated with a decompressive craniectomy for severe ischemic stroke. METHODS: We retrospectively investigated the patient records of 48 patients (26 men, mean age 48 years) suffering from ischemic strokes who underwent craniectomy since 1993. We registrated the preoperative neurological status, the diagnostic data as well as the operative procedure. The outcome was assessed using the Barthel Index, the Glasgow outcome score and a questionnaire to assess the quality of life according to Blau consisting of eleven items at follow-up. FINDINGS: The mortality rate was 26%, age correlated to mortality (44.5 versus 60.3 years GOS 1, mean, p<0.0006). Craniectomy without dura patch correlated to mortality (58% versus 14% GOS 1 with dura patch, p<0.005). The quality of life index was 6 points mean. The quality of life index did neither differ significantly between patients with left or right sided lesions nor in patients with and without aphasia. 83% of the surviving patients and/or dependents would agree to surgery in the future. CONCLUSION: Despite the fact that some patients remain in a poor neurological condition, quality of life after decompressive surgery for ischemic stroke seems to be acceptable to the patients.

Adult↗
PubMed2005

Factors affecting the outcome of decompressive craniectomy for large hemispheric infarctions: a prospective cohort study.

BACKGROUND: Although surgical decompression of large hemispheric infarction is often a life-saving procedure, many patients remain functionally dependent. The aims of this study were to identify specific factors that can be used to predict functional outcome, thus establish predictive criteria to reduce poor surgical results. METHOD: In this non-randomized prospective study, we performed decompressive craniectomy in 32 patients (age range, 27 to 77 years) with large hemispheric infarctions. Based on their modified Rankin Score (RS), which was calculated 6 months postoperatively, patients were divided into two functional groups: good (RS 0-3, n = 7) and poor (RS 4-6, n = 25). The characteristics of the two groups were compared using statistical analysis. FINDINGS: One-month mortality was 31%. However, most of the surviving patients were severely disabled (RS 4 or 5), and 6-month total mortality reached 50%. Increased age (> or = 60 years) (P = 0.010), preoperative midline shift greater than 10 mm (P = 0.008), low preoperative Glasgow Coma Score (GCS < or = 7) (P = 0.002), presence of preoperative anisocoria (P = 0.032), early (within the first three days of the stroke) clinical deterioration (P = 0.032), and an internal carotid artery infarct (P = 0.069) were the positive predictors of a poor outcome. INTERPRETATION: We view decompressive craniectomy for space-occupying large hemispheric infarction as a life-sparing procedure that sometimes yields good functional outcomes. A dominant hemispheric infarction should not be an exclusion criterion when deciding to perform this operation. Early operation and careful patient selection based on the above-mentioned factors may improve the functional outcome of surgical management for large hemispheric infarction.

Adult↗
PubMed2005

Does posterior fossa decompression improve oculomotor and vestibulo-ocular manifestations in Chiari 1 malformation?

BACKGROUND: Oculomotor and vestibulo-ocular manifestations are associated with Chiari 1 malformation. Reports of the results of decompression of CM1 in resolution of these manifestations are limited. METHODS: A retrospective review of case notes were undertaken from Jan 1998 to March 2003 of all the cases undergoing posterior fossa decompressions by the senior author. Forty patients were identified of which 12 had oculomotor and vestibulo-ocular manifestations. RESULTS: Oculomotor and vestibulo-ocular symptoms were present in seven patients and eleven patients had clinical signs. There were only 2 patients who had symptoms and no objective findings. There was complete resolution of oculomotor and vestibulo-ocular manifestations in 8/12 patients and partial improvement in another one, leading to improvement in 9/12 patients. The mean time span to complete resolution was 15.5 months (range 3-71 months). CONCLUSION: Posterior fossa decompression appears to be highly effective in causing complete resolution of disabling oculomotor and vestibule-ocular manifestations in most cases of CM1.

Adolescent↗
PubMed2006

Frequency and prognosis of delayed facial palsy after microvascular decompression for hemifacial spasm.

BACKGROUND: Microvascular decompression (MVD) for hemifacial spasm (HFS) provides a long-term cure rate. Delayed facial palsy (DFP) is not an unusual complication, but it has only been sporadically described in the literature. The purpose of this report is to evaluate the incidence of delayed facial palsy after MVD and its clinical course and final results. METHODS: From January, 1998 to April, 2004, 410 patients underwent microvascular decompression for hemifacial spasm at our Institute. During this time, 21 patients (5.4%) developed delayed facial weakness; eighteen of them were given steroid medication and they were followed up in the out-patient clinic. FINDINGS: Twenty-one patients developed DFP after microvascular decompression an incidence of 5.4%. There were seventeen women (81.0%) among the 21 patients with DFP who were included in this study. In twenty of them, the symptoms of HFS improved completely after the operation, but the spasm remained with one of them. The onset of palsy occurred between postoperative day 7 and 23 (average: 12.1 days). The palsy was at least Grade II or worse on the House-Brackmann (HB) scale. The time to recovery averaged 5.7 weeks (range: 25 days-17 weeks); 20 patients improved to complete recovery and 1 patient remained with minimal weakness, as Grade II on the HB scale, at the follow-up examination. CONCLUSION: Our findings demonstrated that the incidence of DFP was not so low as has been reported the literature, and it did not have any striking predisposing factors. Even though the degree of facial palsy was variable, almost all patients exhibited a complete recovery without any further special treatment. The etiology of DFP and its association with herpes infection should be further clarified.

Adult↗
PubMed2006

Transcranial embolization of a transverse-sigmoid sinus dural arteriovenous fistula carried out through a decompressive craniectomy.

We report a case of dural arteriovenous fistula (DAVF) of the transverse-sigmoid sinus presenting with intraventricular hemorrhage. Cerebellar infarction developed after transarterial embolization, and decompressive craniectomy was performed to relieve the mass effect. Through the bone window of the decompressive craniectomy, transcranial puncture of the transverse sinus and coil occlusion of the fistula were successfully performed. Decompressive craniectomy may provide an opportunity to occlude DAVFs which cannot be occluded by the transarterial or transvenous approach.

Central Nervous System Vascular Malformations↗
PubMed2000

Noncontiguous spinal metastases and plasmocytomas should be operated on through a single posterior midline approach, and circumferential decompression should be performed with individualized reconstruction.

BACKGROUND: In noncontiguous spinal metastatic disease, anterior or combined anterior-posterior surgery is an effective treatment. The objective of this study is to investigate whether circumferential decompression through a single-stage posterior midline approach with individualized spinal reconstruction can still achieve comparable results for functional improvement and for maintenance of spinal alignment in the absence of the risks associated with the more invasive transcavitary or combined approaches. METHOD: Seventeen patients with noncontiguous spinal metastases and plasmocytomas at one or two adjacent levels were included in this series. Circumferential decompression was obtained with anterior reconstruction and posterior fixation in ten patients, and with posterior instrumentation alone in seven patients. Postoperatively the patients were prospectively followed, and their functional status and spinal alignment were periodically evaluated. FINDINGS: Fourteen patients died from progression of their underlying cancer. Their mean survival time was 8 months (range: 1 to 21 months). Three survivors were evaluated at 10, 4 and 3 months respectively. At one month after surgery, 14 patients (82%) showed neurological improvement. Of 10 preoperative nonambulators, seven regained walking capacity. Five patients who were ambulatory with assistance improved to full functional independence. Local tumour recurrence was recorded in one patient after subtotal vertebrectomy for a plasmocytoma at L5. No other tumour recurrences were noted. In one patient a partial loss of correction occurred at T6 - without functional deterioration, however. Spinal alignment was maintained in all other patients who became or remained ambulatory. No major intra-operative complications or peri-operative deaths occurred. CSF leakage was recorded as the most common complication in four patients. INTERPRETATION: Circumferential decompression and spinal reconstruction through a single-stage posterior midline approach is feasible and effective. The extent of surgery can be individualized by means of this technique to the patient's specific problem. In patients with limited life expectancy from metastatic neoplastic disease, the results compare favourably with the more invasive anterior or combined antero-posterior procedures.

Adult↗
PubMed2001

Aggressive decompressive surgery in patients with massive hemispheric embolic cerebral infarction associated with severe brain swelling.

Massive hemispheric cerebral infarction, also known as malignant infarction, is characterized by rapid clinical deterioration due to brain swelling and downward transtentorial herniation, and is associated with a mortality of 80%. Early patient selection and establishment of the optimum therapeutic modality are important to improve the outcome. Early clinical, computed tomography (CT), and angiographic characteristics were analysed to identify patients with malignant infarction and external and internal decompression was performed, with unco-parahippocampectomy if needed, and the outcomes were compared with those of conservative treatment. Thirty-four of 55 patients admitted with large cerebral infarctions due to embolism showed rapid clinical deterioration due to brain swelling and herniation. These 34 patients were treated under a diagnosis of malignant infarction by decompressive surgical treatment (19 cases) or conservative treatment (15 cases). CT showed significantly higher infarction volume in patients with malignant infarction (288 +/- 62 cm3) compared to patients with non-malignant infarction (200 + 57 cm3, P < 0.001) and angiography showed a higher incidence of recanalization of the occluded vessels in patients with malignant infarction (58%) compared to patients with non-malignant infarction (15%, P < 0.05). Discriminant analysis revealed that an infarction volume of more than 240 cm3 was predictive of malignant infarction with 76.4% accuracy. Basic clinical characteristics on admission and deterioration were not statistically different between the surgically treated and conservatively treated groups of patients with malignant infarction. The shift of midline structures was significantly improved (14 +/- 3.5 to 10 +/- 4.7 mm) after surgical treatment (P < 0.05). compared to deterioration (12 +/- 5.8 to 15 +/- 4.5 mm) after conservative treatment. The mortality was 67% in the conservative group and 16% in the surgical group. Surgical treatment significantly improved the mortality and Glasgow Outcome Scale score (P < 0.01). However, the mean Barthel Index scores of the survivors were not significantly different. An infarct volume of more than 240 cm3 on CT and angiographic recanalization of the occluded artery are predictors of fatal brain swelling after massive cerebral infarction. Decompressive surgical treatment dramatically improves the mortality of massive hemispheric infarction.

Aged↗
PubMed2005

Survival of deep-sea shrimp (Alvinocaris sp.) during decompression and larval hatching at atmospheric pressure.

We report successful larval hatching of deep-sea shrimp after decompression to atmospheric pressure. Three specimens of deep-sea shrimp were collected from an ocean depth of 1157 m at cold-seep sites off Hatsushima Island in Sagami Bay, Japan, using a pressure-stat aquarium system. Phylogenetic analysis of Alvinocaris sp. based on cytochrome c oxidase subunit gene sequences confirmed that these species were a member of the genus Alvinocaris. All 3 specimens survived to reach atmospheric pressure conditions after stepwise 63-day decompression. Two of the specimens contained eggs, which hatched after 10 and 16 days, respectively, of full decompression. Although no molting of the shrimp larvae was observed during 74 days of rearing under atmospheric pressure, the larvae developed conventional dark-adapted eyes after 15 days.

Animals↗
PubMed2001

Avoidance of vascular compression in decompressive surgery for brain edema caused by trauma and tumor ablation.

BACKGROUND: In case of severe brain swelling especially caused by trauma or other operative manipulation (tumor ablation), decompressive craniectomy with durotomy has not resulted in significant chances of recovery. Decompressive craniectomy has been defined only as an option within guidelines. METHOD: A new operative technique was developed to improve the efficacy of decompressive surgery. With an increase in intracranial pressure (ICP) threatening with brainstem herniation, wide bilateral craniectomy was carried out, followed by dura opening and subsequent formation of a vascular tunnel in a simple way--using hemostatic sponge cushions--around the main cortical veins at the entering points of the herniated area. The maintenance of vessel patency prevents the herniated brain segment from venous congestion, i.e., from further swelling and necrosis. RESULTS: Twenty operations with traumatic brain edema were performed using this vascular tunnel method. All patients were exposed to surgery in the state of coma. One operation was performed after tumor removal. The results were promising in comparison with the well-known surgical or conservative treatment. DISCUSSION: Applying very strict selection criteria (Glasgow coma scale < 6, signs of severe edema on CT, or intracranial pressure permanently > or = 30 mmHg) in this small series of patients with severe brain injury, good results were achieved using the new operative technique. In case of postoperative edema after tumor ablation, it also showed promising results.

Adult↗
PubMed1980

Computation of decompression schedules for single inert gas-oxygen dives using a hand-held programmable calculator.

An algorithm for on-site computation with a hand-held programmable calculator (TI-59, Texas Instruments) of single inert-gas decompression schedules is described. This program is based on Workman's 'M-value' method. It can compute decompression schedules with changes in the oxygen content of the breathing mixture and extension of stay at any decompression stop. The features of the program that enable calculation of atypical dive profiles, along with the portability of small calculators, would make such an algorithm suitable for on-site applications. However, since dive profiles generated by the program have not yet been tested, divers are warned not to generate schedules until their safety has been established by field tests.

Computers↗
PubMed1980

Cardiopulmonary consequences of decompression stress.

Clinically undetectable venous gas emboli (VGE) can be routinely demonstrated in both animals and men undergoing clinically uneventful decompression from hyperbaric environments. The effect of VGE on gas exchange and pulmonary hemodynamics in this setting is unclear. We therefore have studied the cardiopulmonary effects of clinically uneventful decompression on unanesthetized sheep. Sheep were instrumented with a femoral arterial catheter, Swan-Ganz catheter, chronic tracheostomy, and were loosely restrained in the prone position. Following baseline measurements of pulmonary artery pressure (pPA), mean pulmonary artery wedge pressure (pPAw), cardiac output (CO), arterial and mixed venous blood gases, Doppler ultrasonic bubble detection, and V/Q scans using 133Xe, the animals were exposed to: (a) a 15-min exposure to 6.03 ATA (n = 8), (b) a 17.5-min exposure to 6.03 ATA, or (c) a 15-min control period at 1 ATA (n = 7). All measured parameters remained unchanged in the control group. VGE were detected in all animals exposed to pressure. In both exposure groups CO fell 20% (P < 0.05) and pulmonary vascular resistance (PVR) rose 60% (P < 0.05) compared to the control group. This rise in PVR was significantly in excess of that predicted for the observed fall in CO. Analysis of pPA and pPAw suggested neither right nor left ventricular failure. No significant abnormalities of gas exchange were detected. V/Q scans remained unchanged in all animals. We conclude that CO and PVR are altered by clinically uneventful decompression stress.

Animals↗
PubMed1984

Ex vivo human platelet aggregation induced by decompression during reduced barometric pressure, hydrostatic, and hydrodynamic (Bernoulli) effect.

Decompression of human platelet-rich plasma (PRP) in siliconized glass or plastic to 380 mm Hg for 3 hours at 38 degrees C produced platelet aggregation independent of pO2. Aggregation also took place when PRP was compressed to 8,000 PSI and then decompressed slowly to one atmosphere (14.7 PSI) without gas bubble formation. Platelets also aggregated when plasma was decompressed hydrodynamically (Bernoulli effect) at room temperature. It was also found that the drugs piracetam (2-oxypyrolidine acetamide) and pentoxifylline (1-(5-oxohexyl)-theobromine) at 0.5 and 1.0 mM prevent thrombocyte aggregation. Implications for mountain sickness are discussed.

Atmospheric Pressure↗
PubMed1991

European EVA decompression sickness risks.

For the first manned flight of Hermes there will be a capability of performing EVA. The European EVA Space Suit will be an anthropomorphic system with an internal pressure of 500 hPa of pure oxygen. The pressure reduction from the Hermes cabin pressure of 1013 hPa will induce a risk for Decompression Sickness (DCS) for the EVA crewmember if no adequate protective procedures are implemented. Specific decompression procedures have to be developed. From a critical review of the literature and by using knowledge gained from research conducted in the past in the fields of diving and aerospace medicine safe protective procedures are proposed for the European EVA scenario. An R factor of 1.2 and a tissue half-time (t1/2) of 360 minutes in a single-tissue model have been identified as appropriate operational values. On the basis of an acceptable risk level of approximately 1%, oxygen prebreathing times are proposed for (a) direct pressure reduction from 1013 hPa to a suit pressure of 500 hPa, and (b) staged decompression using a 700 hPa intermediate stage in the spacecraft cabin. In addition, factors which influence individual susceptibility to DCS are identified. Recommendations are also given in the areas of crew selection and medical monitoring requirements together with therapeutic measures that can be implemented in the Hermes scenario. A method for demonstration of the validity of proposed risks and procedures is proposed.

Aerospace Medicine↗
PubMed2006

Transcaruncular orbital decompression: an alternate procedure for Graves ophthalmopathy with compressive optic neuropathy.

PURPOSE: To study the efficacy of transcaruncular orbital apex decompression for Graves ophthalmopathy with compressive optic neuropathy nonresponsive to pulse corticosteroids. DESIGN: Retrospective, interventional case series study. METHODS: From August 1999 to November 2003, transcaruncular orbital decompression was performed in 22 consecutive Graves ophthalmopathy patients with compressive optic neuropathy refractory to pulse corticosteroids. The average period of corticosteroid treatment was 16.1 +/- 5.2 days. Main outcome measures were preoperative and postoperative best-corrected vision, Hertel exophthalmometry, 100-hue color sensation test, visual evoked potential, visual field, and new-onset diplopia. RESULTS: Visual acuity improved significantly from 1.08 +/- 0.24 logarithm of minimal angle of resolution (logMAR) preoperatively to 0.29 +/- 0.18 logMAR postoperatively (P < .0001). Average improvement in retinal sensitivity was 9.4 +/- 8.2 dB, in P(100) value of visual evoked potential was 27.5 +/- 20.1, and in "total errors" of the 100-hue test was 309.9 +/- 214.3 after surgery. Average retroplacement effect was 3.7 +/- 1.6 mm. Statistical analysis showed significant differences between preoperative and postoperative measurements for all above parameters (P < .0001). New-onset diplopia occurred in 38% of patients. There were no complications specifically attributable to the transcaruncular technique. CONCLUSIONS: The transcaruncular approach offers access to the medial and inferior wall for orbital apex decompression in Graves ophthalmopathy patients with compressive optic neuropathy refractory to pulse corticosteroids. Advantages over other approaches included no external scar, less damage to adjacent tissue, and wide exposure to the entire medial wall.

Adult↗
PubMed2006

[Decompressive craniectomy and intracranial hypertension].

Decompressive craniectomy was purposed for the treatment of refractory intracranial hypertension after head injury. This review discusses results obtained by this surgery in severe head trauma. Several studies have confirmed a reduction in intracranial pressure secondary to decompressive craniectomy. Mortality decreased and the proportion of good outcome of the survivors increased. These results have not been confirmed prospectively, and indications have to be clarified. The positive effects of decompressive craniectomy compared to barbiturate or hypocapnia in the "second tier therapy" in refractory intracranial hypertension could be interesting to evaluate.

Craniocerebral Trauma↗
PubMed2006

[Decompression sickness accident management in remote areas. Use of immediate in-water recompression therapy. Review and elaboration of a new protocol targeted for a mission at Clipperton atoll].

In-Water Recompression (IWR) is defined as a treatment of decompression sickness by immediate underwater recompression after the onset of symptoms in remote areas where hyperbaric chambers are not available. At least three methods of IWR have been published. They used pure oxygen breathing for prolonged periods of time at a depth of 9 m. IWR effectiveness in comparison with standard recompression techniques has not been assessed. IWR should be used in remote localities as an immediate measure to stop the evolution of decompression illness before evacuating the victim for subsequent treatment to the nearest hyperbaric facility. Resulting from environmental conditions, the risks of drowning and hypothermia are the most often quoted, pure oxygen breathing at 9 m can also expose to acute oxygen toxicity. The objectives of this work are: first, to examine existing published methods of IWR; second, to propose a new method of IWR. All published methods of IWR involve victim returning underwater for a long period of time. But dehydration due to a long period of immersion can worsen symptoms of decompression illness and acute oxygen toxicity is also related to the duration of the exposition. In response to these considerations we developed a shorter method of conducting IWR specifically targeted for a diving mission at Clipperton atoll in the Northern Pacific Ocean.

Animals↗