Brian Willis

Complications of posterior cranial fossa surgery―an institutional experience of 500 patients

BACKGROUNDnThe complication of the posterior fossa surgery is seldom described in the literature. The purposes of this retrospective study are to draw attention to the potential complications associated with posterior fossa surgery and to critically review the predisposing factors that might influence the complication rate.nnnMETHODSnWe undertook a 10-year (1992-2002) retrospective study of all posterior fossa surgery performed at LSUHSC. A total of 500 patients were obtained from the operation database, and they were categorized into 5 groups based on the surgical approaches: (1) cerebellopontine angle lesion, (2) microvascular decompression for facial pain and spasm, (3) cerebellar lesions, (4) Chiari I decompression, and (5) petroclival lesions. Data collected for analysis included patient demographics, pathological characteristics of the lesions, and the postoperative complications that occurred as unexpected and undesirable events that prolonged hospital stay and may require surgical/medical intervention.nnnRESULTSnOf the 500 patients reviewed, 220 (44%) patients had tumor resections at the cerebellopontine angle; 110 (22%) patients had microvascular decompression for trigeminal neuralgia and hemifacial spasm; 86 (17.2%) patients had cerebellar lesions; 60 (12%) patients had Chiari I decompression; and 24 (4.8%) patients required transpetrosal approaches for petroclival lesions. The overall complication rate in our study was 31.8%, affecting 159 patients. Cerebrospinal fluid leaks were the most frequently encountered, presenting in 65 (13%) patients followed by meningitis in 46 (9.2%) patients, wound infection in 35 (7%) patients, and CN palsies in 24 (4.8%) patients. Other complications that were observed to develop almost exclusively in patients undergoing cerebellar parenchymal tumor resection included cerebellar edema in 25 (5%) patients, hydrocephalus in 23 (4.6%) patients, cerebellar hematoma in 15 (3%) patients, and cerebellar mutism in 6 (1.2%) patients. The overall mortality rate related to surgery was 2.6% occurring in 13 patients.nnnCONCLUSIONnPosterior fossa surgery involves greater morbidity and mortality and has a wider variety of complications than surgery in the supratentorial compartment. These complications may be avoided by careful perioperative planning, strict adherence to aseptic technique, meticulous microsurgical dissection, proper wound closure, and the judicious use of prophylactic agent. A thorough understanding of the patients history, neurological findings, imaging studies, operative anatomy, as well as all potential adverse events associated with the procedure is also essential to minimize complications.

Intracranial aneurysms and cocaine abuse: analysis of prognostic indicators.

OBJECTIVEnThe outcome of subarachnoid hemorrhage associated with cocaine abuse is reportedly poor. However, no study in the literature has reported the use of a statistical model to analyze the variables that influence outcome.nnnMETHODSnA review of admissions during a 6-year period revealed 14 patients with cocaine-related aneurysms. This group was compared with a control group of 135 patients with ruptured aneurysms and no history of cocaine abuse. Age at presentation, time of ictus after intoxication, Hunt and Hess grade of subarachnoid hemorrhage, size of the aneurysm, location of the aneurysm, and the Glasgow Outcome Scale score were assessed and compared.nnnRESULTSnThe patients in the study group were significantly younger than the patients in the control group (P < 0.002). In patients in the study group, all aneurysms were located in the anterior circulation. The majority of these aneurysms were smaller than those of the control group (8 +/- 6.08 mm versus 11 +/- 5.4 mm; P = 0.05). The differences in mortality and morbidity between the two groups were not significant. Hunt and Hess grade (P < 0.005) and age (P < 0.007) were significant predictors of outcome for the patients with cocaine-related aneurysms.nnnCONCLUSIONnCocaine use predisposed aneurysmal rupture at a significantly earlier age and in much smaller aneurysms. Contrary to the published literature, this group did reasonably well with aggressive management.

Hematoma of the ligamentum flavum in the lumbar spine:: Case report

Herniated nucleus pulposis, spondylotic spinal canal stenosis, neoplasms, infection, and spontaneous epidural hematoma [3,7,9] are the most common causes of spinal root and canal compression in the fourth to sixth decades of life. Ligamentum flavum hematoma, which is actually a type of epidural hematoma, is an extremely rare cause of spinal root or canal compression. We report the case of a 67-year-old man with a ligamentum flavum hematoma compressing the spinal canal at the L2-L3 level.

Ventriculoperitoneal shunt complications in hydrocephalus patients with intracranial tumors: an analysis of relevant risk factors

Patients with intracranial tumors are predisposed to persistent hydrocephalus, often requiring a permanent CSF diversion procedure with shunts. This study reviews the long-term experience with ventriculoperitoneal shunts for the management of hydrocephalus in patients with intracranial tumors. Patients with intracranial tumors who underwent ventriculoperitoneal shunt placement for hydrocephalus from October 1990 to October 2009 were included in this study. During the 19-year period, medical charts, operative reports, imaging studies, and clinical follow- up evaluations were reviewed and analyzed retrospectively for all patients. A total of 187 intracranial tumor patients with hydrocephalus were included. The median follow up was 391xa0days. Malignant tumors were present in 40% of the patients. Overall shunt failure was 27.8%. Single shunt revision occurred in 13% of the patients and 14% had multiple shunt revision. Tumor histology, age and a procedure prior to shunt placement (ventriculostomy/Ommaya reservoirs) were significantly associated with the shunt revisions. Shunt system replacement and proximal shunt complication were significantly attributed to multiple shunt revisions. The overall shunt revision within 3xa0months, 6xa0months, 1xa0year and 5xa0years was 17.7%, 18.7%, 19.8% and 24.1%, respectively. The results of the study demonstrate that VP shunting is an effective for the management of hydrocephalus in patients with intracranial tumors. The overall incidence of shunt revision was 27.8%. Age, tumor histology, and a procedure prior to shunt placement (ventriculostomy/Ommaya reservoirs) were significantly associated with the shunt revisions. Additional studies using minimally invasive techniques are being explored for the management of hydrocephalus in patients with intracranial tumors.

Hematoma of the ligamentum flavum in the lumbar spine

Herniated nucleus pulposis, spondylotic spinal canal stenosis, neoplasms, infection, and spontaneous epidural hematoma [3,7,9] are the most common causes of spinal root and canal compression in the fourth to sixth decades of life. Ligamentum flavum hematoma, which is actually a type of epidural hematoma, is an extremely rare cause of spinal root or canal compression. We report the case of a 67-year-old man with a ligamentum flavum hematoma compressing the spinal canal at the L2-L3 level.

Congenital Chiari malformations.

Chiari malformation is the commonest anomaly of the craniovertebral junction involving both the skeletal as well as the neural structures. This entity has rapidly evolved over the past decade with newer visualization techniques, thus posing new challenges to diagnosis and management. This review includes the developmental theories, the latest nomenclature and existing treatment modalities of this interesting anomaly. Five theories tried to explain the malformation of the hindbrain and the neuraxis but no single theory completes the development of embryonic defects. Several atypical presentations have been reported with either incidental/asymptomatic features resulting in further classifications. The new magnetic resonance imaging flow techniques attempt to substantiate the clinical presentations and correlate with the abnormality which can be subtle in correlation. Surgical correction to improve the cranial volume, decrease the hydrocephalus and improve flow across the foramen magnum is the mainstay but needs to be tailored to a given type of malformation. Further clinical and imageological studies, especially longitudinal natural history, might improve our understanding of the atypical/asymptomatic presentations and the management that is currently available.

Pathological evaluation of intervertebral disc tissue specimens after routine cervical and lumbar decompression. A cost-benefit analysis retrospective study.

BACKGROUNDnAfter decompression of cervical and lumbar nerve roots for radicular pain, pathological evaluation of the extracted disc material is commonly performed. Although histological examination rarely detects clinically significant unsuspected disease, it remains a common practice in most hospitals in the United States. To determine the cost-effectiveness of this routine practice, we conducted a retrospective study. The results are contained within this report.nnnMETHODSnUsing the University Neurosurgery database, we retrospectively identified 1,387 patients who had spinal decompression surgery (laminectomy and/or discectomy). These cases were broadly classified into routine and non-routine cases depending on the preoperative diagnosis. Benign and noninfectious cases were classified as routine; malignant and all other cases were classified as nonroutine. We reviewed the medical records and pathology reports of these routine and nonroutine cases in an attempt to study the efficacy of the pathological evaluation of the disc material. The cost-benefit value of histopathology in these cases was analyzed, retrospectively.nnnRESULTSnIn all routine cases, the histopathology was consistent with benign disc disease and yielded no additional information that could have altered the treatment plan. In the nonroutine cases, however, histopathology was significant in the management of the patient. The cost factor for pathological study was the same for both case groups.nnnCONCLUSIONSnPathological study of intervertebral disc specimens is cost beneficial only in cases with significant preoperative clinical diagnoses. Pathological evaluation of routine herniated nucleus pulposus extracted during decompressive surgeries is not warranted.

Management of carotid artery injuries: Louisiana State University Shreveport experience

Background nTraumatic carotid artery injury is an infrequently encountered surgical entity. Carotid artery injuries in polytrauma patients can be easily missed in the absence of clinical findings and/or presence of confounding concurrent injuries. nMethods nBetween 1991 and 1998, 23 patients were diagnosed with various carotid artery injuries at the trauma center of Louisiana State University Health Sciences Center, Shreveport, Louisiana. Injuries were assessed by angiography and/or surgical exploration of the neck. Clinical presentations, radiologic features, management strategies, and neurologic outcomes were statistically analyzed and compared with the existing literature. nResults nTwelve patients (52%) had penetrating carotid artery injuries, while 11 (48%) had blunt trauma. The diagnosis of carotid injury was significantly delayed in the group with blunt trauma as opposed to those with penetrating wounds. Surgical repair was performed in 6 (26%) patients; 2 (8%) underwent balloon occlusion, while ligation was conducted in 2 (8%) patients. Thirteen patients (57%) were treated conservatively with anticoagulants. Six patients (26%) died, while another 6 (26%) had permanent neurologic deficit. Mortality and morbidity was significantly higher in the group with penetrating injuries. A statistical analysis showed that multi-level carotid injury (p < 0.002) and increasing age (p < 0.001) had a significantly higher mortality. nConclusions nInjury to carotid arteries results in significant mortality and morbidity. Our results indicate that penetrating carotid injury at more than one level carries higher mortality and morbidity rates than blunt injury. Furthermore, early identification of the injured segment may favorably influence the outcome for such patients.

How bullet trajectory affects outcomes of civilian gunshot injury to the spine.

We analysed retrospectively the effect of missile trajectory on outcomes from civilian gunshot injury to the spine (GSIS) between 1994 and 2008. Most of the 98 patients were male (88.8%). A minority (8%) of patients had multiple column injuries and a bone or bullet fragment in the spinal canal (14%). Neurologic injury was seen in 33%; and external bracing was applied to 30% of patients. The odds of bracing among patients with multiple levels of damage were 3.4 times than for patients with a single vertebral level of damage. The odds of paralysis among black patients were 6.33 times the odds among non-black patients. The odds of paralysis among patients with a fragment in the spinal canal were 12.99 times those without. We conclude that the supero-inferior trajectory affects the number of vertebral levels involved and consequently the need for bracing. The lateral trajectory affects neurological outcomes.

Late presentation of tethered spinal cord in a 73-year-old patient

JAGS 49:682–690, 2001