Delayed Symptomatic Lumboperitoneal Shunt Malfunction 18 Years After Stability

Clinical Correspondence Section Editors: Robert Avery, DO Karl C. Golnik, MD Caroline Froment, MD, PhD An-Guor Wang, MD Delayed Symptomatic Lumboperitoneal Shunt Malfunction 18 Years After Stability Ryung Lee, BS, Peter Mortensen, MD, Subahari Raviskanthan, MBBS, Saeed Sadrameli, MD, Nagham Al-Zubidi, MD, Andrew G. Lee, MD I diopathic intracranial hypertension (IIH) is a condition primarily affecting overweight/obese women of childbearing age. The modified Dandy criteria requires patients to only have symptoms (headaches and visual symptoms), signs (papilledema, nonlocalizing sixth nerve palsy), and radiographic features (increased fluid in the optic nerve sheath, empty sella, flattening of the globe) of elevated ICP. By criteria, the cerebrospinal fluid (CSF) should be normal, with an elevated ICP on lumbar puncture. Lumboperitoneal shunting (LPS) is an established surgical treatment for the management of IIH. CSF diversion procedures, including LPS, are shown to improve visual and headache symptoms, typically after maximum medical therapy has failed. In recent years, ventriculoperitoneal (VP) shunts have become the preferred CSF diversion procedure in most centers due to a lower complication/revision rate and lower average hospital length of stay. Most LPS complications are mechanical or infectious, but failure from obstruction, overdrainage, catheter migration or fracture, and abdominal complications have all been reported (1). We present a case of delayed symptomatic LPS malfunction presenting 18 years after insertion for IIH. To our knowledge, this case is the longest duration of time from placement to symptomatic LPS failure in an adult with IIH in the English-language ophthalmic literature. A 59-year-old woman was admitted to the hospital for worsening headache, radicular pain, blurred vision, and progressively right eye (right eye) “tunnel vision.” Her med- ical history was significant for IIH diagnosed 30 years ago. She was initially managed medically for 12 years but required LPS and optic nerve sheath fenestration right eye due to intolerance of acetazolamide, with good subsequent visual stabilization and headache resolution. She did not suffer from hypertension or obstructive sleep apnea. Her surgical, social, and family histories were noncontributory. She reported gradual weight gain over the past 30 years. Thirty years after her initial presentation, the patient had sudden-onset bilateral radicular sounding pain while moving her washing machine, persistent and progressing over the next few weeks. Initial workup with MRI of the spine showed only cervical degenerative joint disease with some foraminal narrowing. She progressively developed worsening vision, increasing headaches, and nausea and was referred to the neuroophthalmology service at the Houston Methodist Hospital. On neuro-ophthalmic examination, her visual acuity with 20/30 in the right eye and 20/20 in the left eye (left eye). Her pupils were isocoric with no relative afferent pupillary defect. She had normal intraocular pressures and extraocular motility. Slit-lamp biomicroscopy was normal. Dilated fundus examination showed a 0.3 cup-to-disc ratio with peripapillary atrophy in both eyes (OU) and was otherwise normal. Automated perimetry (automated visual field 24-2) showed a dense superior altitudinal field defect with inferior arcuate defect and enlargement of the blind spot in both eyes, worse than previous. There was thinning of the retinal nerve fiber layer on Department of Ophthalmology, Blanton Eye Institute, Houston Methodist Hospital (RL, PM, SR, NA-Z, AGL), Houston, Texas; and Department of Head and Neck Surgery (NA-Z), Division of Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas; Department of Neurosurgery (SS), Houston Methodist Hospital, Houston Texas; Ophthalmology, Neurology, and Neurosurgery (AGL), Weill Cornell Medicine, New York, New York; and Department of Ophthalmology (AGL, NA-Z), Baylor College of Medicine, University of Iowa Hospitals and Clinics, University of Buffalo (SUNY) UTMB, Galveston and the UT MD Anderson Cancer Center, Houston, Texas. The authors report no conflicts of interest. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s Web site (www. jneuro-ophthalmology.com). Address correspondence to Andrew G. Lee, MD, Blanton Eye Institute, Houston Methodist Hospital, Houston, TX 77030; E-mail: [e-mail] Lee et al: J Neuro-Ophthalmol 2023; 43: e169-e170 FIG. 1. Pelvic x-ray showing discontinuity of the lumboperitoneal shunt catheter at L2–L3 level. e169 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited. Clinical Correspondence FIG. 2. (A, B); Automated visual fields with 24-2 threshold demonstrating changes before (A) and after (B) VP shunt replacement. optical coherence tomography, consistent with diffuse optic atrophy from long-standing IIH. Lumbar puncture revealed an elevated opening pressure of 34 cm H2O, with normal CSF content. Pelvis and spine x-ray revealed displacement of the shunt, with complete discontinuation of the proximal tip of the catheter at the L2-L3 level (Fig. 1). The remainder of the catheter was positioned superficial to the spinous processes with the distal tip of the catheter extending into the right lower quadrant of the abdomen. Repeat MRI of the brain with venogram showed empty sella, posterior flattening of the globe bilaterally, and left transverse sinus stenosis, suggesting overall a recurrence of IIH in the setting of LPS malfunction. A right frontal VP shunt was placed (Medtronic Strata 1.0), with rapid resolution of her headache and nausea, and stabilization of her visual fields (Fig. 2). VP and LP shunt failure is common. In one study of 37 patients treated with 10 VP shunts and 73 LP shunts, more than 64 percent of shunts failed in less than 6 months, and shunt failure was the most common indication for revision (4). Although shunt failure can occur at any time, the longest LP shunt lifespan reported in the literature for IIH is 168 months (this shunt was removed for symptomatic pleural effusions)—other prolonged shunt durations are sum- e170 marized in Supplemental Digital Content (see Table S1, http://links.lww.com/WNO/A575). One possible explanation for the prolonged shunt lifespan in our case is that body mass index is an independent risk factor for LP shunt failure, which may also explain the higher rates of shunt failure in IIH compared with non-IIH patients. At admission, our patient had a body mass index of 26.5 m/kg2. Children typically have a higher risk for developing early shunt complications due to increased mechanical stress or the size of the shunt tubing in the thecal sac, and delayed LPS failure for IIH may be more common in the adult population. Clinicians are likely already aware that surgical procedures for IIH (including CSF shunts or ONSF) often eventually fail. Shunts may fail at any time, and we recognize that asymptomatic shunt failure is a common and likely expected occurrence in most cases of surgically treated IIH. However, some shunted patients are shunt dependent and symptomatic, potentially vision threatening, shunt failure can therefore be delayed by years or even decades after asymptomatic stability. Adult patients with a shunt who present with visual loss should be suspected of harboring shunt malfunction until proven otherwise. STATEMENT OF AUTHORSHIP Conception and design: R. Lee, P. Mortensen, S. Raviskanthan, S. Sadrameli, N. Al-Zubidi, A. Lee. Acquisition of data: R. Lee, P. Mortensen, S. Raviskanthan, S. Sadrameli, N. Al-Zubidi, A. Lee. Analysis and interpretation of data: R. Lee, P. Mortensen, S. Raviskanthan, S. Sadrameli, N. Al-Zubidi, A. Lee. Drafting the manuscript: R. Lee, P. Mortensen, S. Raviskanthan, S. Sadrameli, N. Al-Zubidi, A. Lee. Revising the manuscript for intellectual content: R. Lee, P. Mortensen, S. Raviskanthan, S. Sadrameli, N. Al-Zubidi, A. Lee. Final approval of the completed manuscript: R. Lee, P. Mortensen, S. Raviskanthan, S. Sadrameli, N. Al-Zubidi, A. Lee. REFERENCES 1. Sunderland GJ, Jenkinson MD, Conroy EJ, Gamble C, Mallucci CL. Neurosurgical CSF diversion in idiopathic intracranial hypertension: a narrative review. Life (Basel). 2021;11:393. 2. Greener DL, Akarca D, Durnford AJ, Ewbank F, Buckland GR, Hempenstall J. Idiopathic intracranial hypertension: shunt failure and the role of obesity. World Neurosurg. 2020;137:e83–e88. 3. Chumas PD, Kulkarni AV, Drake JM, Hoffman HJ, Humphreys RP, Rutka JT. Lumboperitoneal Shunting Neurosurg. 1993;32:376–383. 4. Rangwala LM, Liu GT. Pediatric idiopathic intracranial hypertension. Surv Ophthalmol. 2007;52:597–617. 5. Elder BD, Sankey EW, Goodwin CR, Jusué-Torres I, Khattab MH, Rigamonti D. Outcomes and experience with lumbopleural shunts in the management of idiopathic intracranial hypertension. World Neurosurg. 2015;84:314–319. Lee et al: J Neuro-Ophthalmol 2023; 43: e169-e170 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited.