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Table of Contents    
Year : 2022  |  Volume : 70  |  Issue : 4  |  Page : 1676-1677

Syndrome of the Trephined Following Ventriculo-Peritoneal Shunt in a Post-Traumatic Hydrocephalus Patient

Department of Neurosurgery, Medical Superspecialty Hospital, Kolkata, West Bengal, India

Date of Submission27-Apr-2020
Date of Decision18-Jul-2020
Date of Acceptance18-Oct-2020
Date of Web Publication30-Aug-2022

Correspondence Address:
Indrajit Rana
Medical Superspecialty Hospital, 127 Eastern Metropolitan Bypass, Mukundapur, Kolkata - 700 099, West Bengal
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0028-3886.355147

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How to cite this article:
Rana I, Tripathy LN, Jain H. Syndrome of the Trephined Following Ventriculo-Peritoneal Shunt in a Post-Traumatic Hydrocephalus Patient. Neurol India 2022;70:1676-7

How to cite this URL:
Rana I, Tripathy LN, Jain H. Syndrome of the Trephined Following Ventriculo-Peritoneal Shunt in a Post-Traumatic Hydrocephalus Patient. Neurol India [serial online] 2022 [cited 2022 Oct 7];70:1676-7. Available from: https://www.neurologyindia.com/text.asp?2022/70/4/1676/355147


Syndrome of the Trephined (SOT) or sinking skin flap syndrome is a known but rare complication following large craniectomy. Conversion of the cranium from a closed box to an open box alters the effect of barometric pressure on brain and thus affects cerebrospinal fluid (CSF) dynamics. Decompressive craniectomy (DC) has been found to be associated with development of post-traumatic hydrocephalus (PTH) due to mechanical blockage around convexities or inflammation of arachnoid granulations by post-surgical debris.[1]

We report a case of 38-year-old man who underwent right-sided DC for subdural hematoma following traumatic head injury. 4 months following DC, he was taken to emergency room with history of altered sensorium (GCS E2V2M5) and seizure episodes. Non-contrast computed tomography (NCCT) scan of brain showed hydrocephalus. After counseling with the patient relatives, insertion of ventriculo-peritoneal (VP) shunt was planned on emergency basis. We also mentioned about the need of cranioplasty as a planned surgery in near future. With-in 2 days after insertion of left-sided medium pressure VP shunt, he developed SOT. NCCT scan of brain revealed right-sided craniectomy defect with sunken skin flap, midline shift and slit-like ventricles [Figure 1]. The shunt was tied off as a bedside procedure, but it didn't cause any improvement in sensorium and ventricular size remained unaltered. He underwent autologous cranioplasty. NCCT brain done after 12 hours of cranioplasty showed ventricular dilatation. The shunt was reopened and it was working as confirmed by the bedside shunt tapping test. His sensorium (GCS E4V5M6) and cognitive function were improved.
Figure 1: (a) NCCT brain showing hydrocephalus with evidence of right-sided DC; (b) Sunken skin flap, midline shift and slit-like ventricles - features of SOT; (c) Following shunt tie-off there is no change in ventricular size; (d) Ventricular dilatation and reversal of SOT following cranioplasty

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SOT usually occurs after months of DC. CSF diversion procedure can precipitate this phenomenon[2] as it happened in our case. From India, there are very few case reports of SOT following VP shunt.[3],[4] When the atmospheric pressure overwhelms the intracranial pressure, there is inward shifting of the scalp over the surgery site and paradoxical herniation of brain occurs. The CSF drainage exacerbates this effect by creating a pressure gradient through craniectomy site. The primary goal of treatment is to reverse the effect of external pressure by cranioplasty. Various experiments showed increase in CSF motion, superior sagittal sinus pressure and cerebral expansion after cranioplasty are due to an increase in cerebral blood flow, cerebral metabolism, and improvement in cerebral vascular reserve capacity.[5] Literature supporting conservative management in such patients is lacking.[4],[6] Trendelenberg position, intrathecal saline infusion alone seldomly improve the slit ventricles.[4] In our case, temporary occlusion of VP shunt didn't cause any improvement. Following cranioplasty there is a risk of fluid collection and hematoma formation in the subdural space due to the large dead space. In the context of PTH, temporary occlusion of VP shunt before cranioplasty and dural tenting sutures during cranioplasty may help to eliminate the dead space. When autologus bone flap is not available titanium mesh, bone cement, and 3D printed bone flap are the other alternatives.[7]

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form patient relatives have given consent for his images and other clinical information to be reported in the journal. They understand that his name and initials will not be published and due efforts will be made to conceal the identity, but anonymity cannot be guaranteed.

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Conflicts of interest

There are no conflicts of interest.

  References Top

Akins PT, Guppy KH. Sinking skin flaps, paradoxical herniation, and external brain tamponade: A review of decompressive craniectomy management. Neurocritical Care. 2008;9:269-76.  Back to cited text no. 1
Liao CC, Kao MC. Cranioplasty for patients with severe depressed skull bone defect after cerebrospinal fluid shunting. J Clin Neurosci. 2002;9:553-5.  Back to cited text no. 2
Jeyaraj P. Importance of Early Cranioplasty in Reversing the “Syndrome of the Trephine/Motor Trephine Syndrome/Sinking Skin Flap Syndrome”. J Maxillofac Oral Surg. 2015;14:666-73.  Back to cited text no. 3
Garg R, Aggarwal A, Salunke P. Importance of calvaria in cerebrospinal fluid dynamics: A case of ventriculomegaly and sinking flap syndrome after decompressive craniectomy. Asian J Neurosurg. 2018;13:128-9.  Back to cited text no. 4
Fodstad H, Love JA, Ekstedt T, Friden H, Lilliequist B. Effect of cranioplasty on cerebrospinal fluid hydrodynamics in the patients with the syndrome of the trephined. Acta Neurochir. 1984;70:21-30.  Back to cited text no. 5
Annan M, Toffol BD, Hommet C, Mondon K. Sinking skin flap syndrome (or syndrome of trephined) a review. Br J of Neurosurg. 2015;29:314-8.  Back to cited text no. 6
Aydin S, Kucukyuruk B, Abuzayed B, Aydin S, Sanus GZ. Cranioplasty: Review of materials and techniques. J Neurosci Rural Pract. 2011;2:162-7.  Back to cited text no. 7


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